drivers/nfc/trf7970a.c

   1 /*
   2  * TI TRF7970a RFID/NFC Transceiver Driver
   3  *
   4  * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
   5  *
   6  * Author: Erick Macias <emacias@ti.com>
   7  * Author: Felipe Balbi <balbi@ti.com>
   8  * Author: Mark A. Greer <mgreer@animalcreek.com>
   9  *
  10  * This program is free software: you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2  of
  12  * the License as published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/device.h>
  17 #include <linux/netdevice.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/pm_runtime.h>
  20 #include <linux/nfc.h>
  21 #include <linux/skbuff.h>
  22 #include <linux/delay.h>
  23 #include <linux/gpio/consumer.h>
  24 #include <linux/of.h>
  25 #include <linux/spi/spi.h>
  26 #include <linux/regulator/consumer.h>
  27
  28 #include <net/nfc/nfc.h>
  29 #include <net/nfc/digital.h>
  30
  31 /* There are 3 ways the host can communicate with the trf7970a:
  32  * parallel mode, SPI with Slave Select (SS) mode, and SPI without
  33  * SS mode.  The driver only supports the two SPI modes.
  34  *
  35  * The trf7970a is very timing sensitive and the VIN, EN2, and EN
  36  * pins must asserted in that order and with specific delays in between.
  37  * The delays used in the driver were provided by TI and have been
  38  * confirmed to work with this driver.  There is a bug with the current
  39  * version of the trf7970a that requires that EN2 remain low no matter
  40  * what.  If it goes high, it will generate an RF field even when in
  41  * passive target mode.  TI has indicated that the chip will work okay
  42  * when EN2 is left low.  The 'en2-rf-quirk' device tree property
  43  * indicates that trf7970a currently being used has the erratum and
  44  * that EN2 must be kept low.
  45  *
  46  * Timeouts are implemented using the delayed workqueue kernel facility.
  47  * Timeouts are required so things don't hang when there is no response
  48  * from the trf7970a (or tag).  Using this mechanism creates a race with
  49  * interrupts, however.  That is, an interrupt and a timeout could occur
  50  * closely enough together that one is blocked by the mutex while the other
  51  * executes.  When the timeout handler executes first and blocks the
  52  * interrupt handler, it will eventually set the state to IDLE so the
  53  * interrupt handler will check the state and exit with no harm done.
  54  * When the interrupt handler executes first and blocks the timeout handler,
  55  * the cancel_delayed_work() call will know that it didn't cancel the
  56  * work item (i.e., timeout) and will return zero.  That return code is
  57  * used by the timer handler to indicate that it should ignore the timeout
  58  * once its unblocked.
  59  *
  60  * Aborting an active command isn't as simple as it seems because the only
  61  * way to abort a command that's already been sent to the tag is so turn
  62  * off power to the tag.  If we do that, though, we'd have to go through
  63  * the entire anticollision procedure again but the digital layer doesn't
  64  * support that.  So, if an abort is received before trf7970a_send_cmd()
  65  * has sent the command to the tag, it simply returns -ECANCELED.  If the
  66  * command has already been sent to the tag, then the driver continues
  67  * normally and recieves the response data (or error) but just before
  68  * sending the data upstream, it frees the rx_skb and sends -ECANCELED
  69  * upstream instead.  If the command failed, that error will be sent
  70  * upstream.
  71  *
  72  * When recieving data from a tag and the interrupt status register has
  73  * only the SRX bit set, it means that all of the data has been received
  74  * (once what's in the fifo has been read).  However, depending on timing
  75  * an interrupt status with only the SRX bit set may not be recived.  In
  76  * those cases, the timeout mechanism is used to wait 20 ms in case more
  77  * data arrives.  After 20 ms, it is assumed that all of the data has been
  78  * received and the accumulated rx data is sent upstream.  The
  79  * 'TRF7970A_ST_WAIT_FOR_RX_DATA_CONT' state is used for this purpose
  80  * (i.e., it indicates that some data has been received but we're not sure
  81  * if there is more coming so a timeout in this state means all data has
  82  * been received and there isn't an error).  The delay is 20 ms since delays
  83  * of ~16 ms have been observed during testing.
  84  *
  85  * When transmitting a frame larger than the FIFO size (127 bytes), the
  86  * driver will wait 20 ms for the FIFO to drain past the low-watermark
  87  * and generate an interrupt.  The low-watermark set to 32 bytes so the
  88  * interrupt should fire after 127 - 32 = 95 bytes have been sent.  At
  89  * the lowest possible bit rate (6.62 kbps for 15693), it will take up
  90  * to ~14.35 ms so 20 ms is used for the timeout.
  91  *
  92  * Type 2 write and sector select commands respond with a 4-bit ACK or NACK.
  93  * Having only 4 bits in the FIFO won't normally generate an interrupt so
  94  * driver enables the '4_bit_RX' bit of the Special Functions register 1
  95  * to cause an interrupt in that case.  Leaving that bit for a read command
  96  * messes up the data returned so it is only enabled when the framing is
  97  * 'NFC_DIGITAL_FRAMING_NFCA_T2T' and the command is not a read command.
  98  * Unfortunately, that means that the driver has to peek into tx frames
  99  * when the framing is 'NFC_DIGITAL_FRAMING_NFCA_T2T'.  This is done by
 100  * the trf7970a_per_cmd_config() routine.
 101  *
 102  * ISO/IEC 15693 frames specify whether to use single or double sub-carrier
 103  * frequencies and whether to use low or high data rates in the flags byte
 104  * of the frame.  This means that the driver has to peek at all 15693 frames
 105  * to determine what speed to set the communication to.  In addition, write
 106  * and lock commands use the OPTION flag to indicate that an EOF must be
 107  * sent to the tag before it will send its response.  So the driver has to
 108  * examine all frames for that reason too.
 109  *
 110  * It is unclear how long to wait before sending the EOF.  According to the
 111  * Note under Table 1-1 in section 1.6 of
 112  * http://www.ti.com/lit/ug/scbu011/scbu011.pdf, that wait should be at least
 113  * 10 ms for TI Tag-it HF-I tags; however testing has shown that is not long
 114  * enough so 20 ms is used.  So the timer is set to 40 ms - 20 ms to drain
 115  * up to 127 bytes in the FIFO at the lowest bit rate plus another 20 ms to
 116  * ensure the wait is long enough before sending the EOF.  This seems to work
 117  * reliably.
 118  */
 119
 120 #define TRF7970A_SUPPORTED_PROTOCOLS \
 121                 (NFC_PROTO_MIFARE_MASK | NFC_PROTO_ISO14443_MASK |      \
 122                  NFC_PROTO_ISO14443_B_MASK | NFC_PROTO_FELICA_MASK | \
 123                  NFC_PROTO_ISO15693_MASK | NFC_PROTO_NFC_DEP_MASK)
 124
 125 #define TRF7970A_AUTOSUSPEND_DELAY              30000 /* 30 seconds */
 126 #define TRF7970A_13MHZ_CLOCK_FREQUENCY          13560000
 127 #define TRF7970A_27MHZ_CLOCK_FREQUENCY          27120000
 128
 129
 130 #define TRF7970A_RX_SKB_ALLOC_SIZE              256
 131
 132 #define TRF7970A_FIFO_SIZE                      127
 133
 134 /* TX length is 3 nibbles long ==> 4KB - 1 bytes max */
 135 #define TRF7970A_TX_MAX                         (4096 - 1)
 136
 137 #define TRF7970A_WAIT_FOR_TX_IRQ                20
 138 #define TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT       20
 139 #define TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT    20
 140 #define TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF     40
 141
 142 /* Guard times for various RF technologies (in us) */
 143 #define TRF7970A_GUARD_TIME_NFCA                5000
 144 #define TRF7970A_GUARD_TIME_NFCB                5000
 145 #define TRF7970A_GUARD_TIME_NFCF                20000
 146 #define TRF7970A_GUARD_TIME_15693               1000
 147
 148 /* Quirks */
 149 /* Erratum: When reading IRQ Status register on trf7970a, we must issue a
 150  * read continuous command for IRQ Status and Collision Position registers.
 151  */
 152 #define TRF7970A_QUIRK_IRQ_STATUS_READ          BIT(0)
 153 #define TRF7970A_QUIRK_EN2_MUST_STAY_LOW        BIT(1)
 154 #define TRF7970A_QUIRK_T5T_RMB_EXTRA_BYTE       BIT(2)
 155
 156 /* Direct commands */
 157 #define TRF7970A_CMD_IDLE                       0x00
 158 #define TRF7970A_CMD_SOFT_INIT                  0x03
 159 #define TRF7970A_CMD_RF_COLLISION               0x04
 160 #define TRF7970A_CMD_RF_COLLISION_RESPONSE_N    0x05
 161 #define TRF7970A_CMD_RF_COLLISION_RESPONSE_0    0x06
 162 #define TRF7970A_CMD_FIFO_RESET                 0x0f
 163 #define TRF7970A_CMD_TRANSMIT_NO_CRC            0x10
 164 #define TRF7970A_CMD_TRANSMIT                   0x11
 165 #define TRF7970A_CMD_DELAY_TRANSMIT_NO_CRC      0x12
 166 #define TRF7970A_CMD_DELAY_TRANSMIT             0x13
 167 #define TRF7970A_CMD_EOF                        0x14
 168 #define TRF7970A_CMD_CLOSE_SLOT                 0x15
 169 #define TRF7970A_CMD_BLOCK_RX                   0x16
 170 #define TRF7970A_CMD_ENABLE_RX                  0x17
 171 #define TRF7970A_CMD_TEST_INT_RF                0x18
 172 #define TRF7970A_CMD_TEST_EXT_RF                0x19
 173 #define TRF7970A_CMD_RX_GAIN_ADJUST             0x1a
 174
 175 /* Bits determining whether its a direct command or register R/W,
 176  * whether to use a continuous SPI transaction or not, and the actual
 177  * direct cmd opcode or regster address.
 178  */
 179 #define TRF7970A_CMD_BIT_CTRL                   BIT(7)
 180 #define TRF7970A_CMD_BIT_RW                     BIT(6)
 181 #define TRF7970A_CMD_BIT_CONTINUOUS             BIT(5)
 182 #define TRF7970A_CMD_BIT_OPCODE(opcode)         ((opcode) & 0x1f)
 183
 184 /* Registers addresses */
 185 #define TRF7970A_CHIP_STATUS_CTRL               0x00
 186 #define TRF7970A_ISO_CTRL                       0x01
 187 #define TRF7970A_ISO14443B_TX_OPTIONS           0x02
 188 #define TRF7970A_ISO14443A_HIGH_BITRATE_OPTIONS 0x03
 189 #define TRF7970A_TX_TIMER_SETTING_H_BYTE        0x04
 190 #define TRF7970A_TX_TIMER_SETTING_L_BYTE        0x05
 191 #define TRF7970A_TX_PULSE_LENGTH_CTRL           0x06
 192 #define TRF7970A_RX_NO_RESPONSE_WAIT            0x07
 193 #define TRF7970A_RX_WAIT_TIME                   0x08
 194 #define TRF7970A_MODULATOR_SYS_CLK_CTRL         0x09
 195 #define TRF7970A_RX_SPECIAL_SETTINGS            0x0a
 196 #define TRF7970A_REG_IO_CTRL                    0x0b
 197 #define TRF7970A_IRQ_STATUS                     0x0c
 198 #define TRF7970A_COLLISION_IRQ_MASK             0x0d
 199 #define TRF7970A_COLLISION_POSITION             0x0e
 200 #define TRF7970A_RSSI_OSC_STATUS                0x0f
 201 #define TRF7970A_SPECIAL_FCN_REG1               0x10
 202 #define TRF7970A_SPECIAL_FCN_REG2               0x11
 203 #define TRF7970A_RAM1                           0x12
 204 #define TRF7970A_RAM2                           0x13
 205 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS      0x14
 206 #define TRF7970A_NFC_LOW_FIELD_LEVEL            0x16
 207 #define TRF7970A_NFCID1                         0x17
 208 #define TRF7970A_NFC_TARGET_LEVEL               0x18
 209 #define TRF79070A_NFC_TARGET_PROTOCOL           0x19
 210 #define TRF7970A_TEST_REGISTER1                 0x1a
 211 #define TRF7970A_TEST_REGISTER2                 0x1b
 212 #define TRF7970A_FIFO_STATUS                    0x1c
 213 #define TRF7970A_TX_LENGTH_BYTE1                0x1d
 214 #define TRF7970A_TX_LENGTH_BYTE2                0x1e
 215 #define TRF7970A_FIFO_IO_REGISTER               0x1f
 216
 217 /* Chip Status Control Register Bits */
 218 #define TRF7970A_CHIP_STATUS_VRS5_3             BIT(0)
 219 #define TRF7970A_CHIP_STATUS_REC_ON             BIT(1)
 220 #define TRF7970A_CHIP_STATUS_AGC_ON             BIT(2)
 221 #define TRF7970A_CHIP_STATUS_PM_ON              BIT(3)
 222 #define TRF7970A_CHIP_STATUS_RF_PWR             BIT(4)
 223 #define TRF7970A_CHIP_STATUS_RF_ON              BIT(5)
 224 #define TRF7970A_CHIP_STATUS_DIRECT             BIT(6)
 225 #define TRF7970A_CHIP_STATUS_STBY               BIT(7)
 226
 227 /* ISO Control Register Bits */
 228 #define TRF7970A_ISO_CTRL_15693_SGL_1OF4_662    0x00
 229 #define TRF7970A_ISO_CTRL_15693_SGL_1OF256_662  0x01
 230 #define TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648   0x02
 231 #define TRF7970A_ISO_CTRL_15693_SGL_1OF256_2648 0x03
 232 #define TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a   0x04
 233 #define TRF7970A_ISO_CTRL_15693_DBL_1OF256_667  0x05
 234 #define TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669   0x06
 235 #define TRF7970A_ISO_CTRL_15693_DBL_1OF256_2669 0x07
 236 #define TRF7970A_ISO_CTRL_14443A_106            0x08
 237 #define TRF7970A_ISO_CTRL_14443A_212            0x09
 238 #define TRF7970A_ISO_CTRL_14443A_424            0x0a
 239 #define TRF7970A_ISO_CTRL_14443A_848            0x0b
 240 #define TRF7970A_ISO_CTRL_14443B_106            0x0c
 241 #define TRF7970A_ISO_CTRL_14443B_212            0x0d
 242 #define TRF7970A_ISO_CTRL_14443B_424            0x0e
 243 #define TRF7970A_ISO_CTRL_14443B_848            0x0f
 244 #define TRF7970A_ISO_CTRL_FELICA_212            0x1a
 245 #define TRF7970A_ISO_CTRL_FELICA_424            0x1b
 246 #define TRF7970A_ISO_CTRL_NFC_NFCA_106          0x01
 247 #define TRF7970A_ISO_CTRL_NFC_NFCF_212          0x02
 248 #define TRF7970A_ISO_CTRL_NFC_NFCF_424          0x03
 249 #define TRF7970A_ISO_CTRL_NFC_CE_14443A         0x00
 250 #define TRF7970A_ISO_CTRL_NFC_CE_14443B         0x01
 251 #define TRF7970A_ISO_CTRL_NFC_CE                BIT(2)
 252 #define TRF7970A_ISO_CTRL_NFC_ACTIVE            BIT(3)
 253 #define TRF7970A_ISO_CTRL_NFC_INITIATOR         BIT(4)
 254 #define TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE       BIT(5)
 255 #define TRF7970A_ISO_CTRL_RFID                  BIT(5)
 256 #define TRF7970A_ISO_CTRL_DIR_MODE              BIT(6)
 257 #define TRF7970A_ISO_CTRL_RX_CRC_N              BIT(7)  /* true == No CRC */
 258
 259 #define TRF7970A_ISO_CTRL_RFID_SPEED_MASK       0x1f
 260
 261 /* Modulator and SYS_CLK Control Register Bits */
 262 #define TRF7970A_MODULATOR_DEPTH(n)             ((n) & 0x7)
 263 #define TRF7970A_MODULATOR_DEPTH_ASK10          (TRF7970A_MODULATOR_DEPTH(0))
 264 #define TRF7970A_MODULATOR_DEPTH_OOK            (TRF7970A_MODULATOR_DEPTH(1))
 265 #define TRF7970A_MODULATOR_DEPTH_ASK7           (TRF7970A_MODULATOR_DEPTH(2))
 266 #define TRF7970A_MODULATOR_DEPTH_ASK8_5         (TRF7970A_MODULATOR_DEPTH(3))
 267 #define TRF7970A_MODULATOR_DEPTH_ASK13          (TRF7970A_MODULATOR_DEPTH(4))
 268 #define TRF7970A_MODULATOR_DEPTH_ASK16          (TRF7970A_MODULATOR_DEPTH(5))
 269 #define TRF7970A_MODULATOR_DEPTH_ASK22          (TRF7970A_MODULATOR_DEPTH(6))
 270 #define TRF7970A_MODULATOR_DEPTH_ASK30          (TRF7970A_MODULATOR_DEPTH(7))
 271 #define TRF7970A_MODULATOR_EN_ANA               BIT(3)
 272 #define TRF7970A_MODULATOR_CLK(n)               (((n) & 0x3) << 4)
 273 #define TRF7970A_MODULATOR_CLK_DISABLED         (TRF7970A_MODULATOR_CLK(0))
 274 #define TRF7970A_MODULATOR_CLK_3_6              (TRF7970A_MODULATOR_CLK(1))
 275 #define TRF7970A_MODULATOR_CLK_6_13             (TRF7970A_MODULATOR_CLK(2))
 276 #define TRF7970A_MODULATOR_CLK_13_27            (TRF7970A_MODULATOR_CLK(3))
 277 #define TRF7970A_MODULATOR_EN_OOK               BIT(6)
 278 #define TRF7970A_MODULATOR_27MHZ                BIT(7)
 279
 280 #define TRF7970A_RX_SPECIAL_SETTINGS_NO_LIM     BIT(0)
 281 #define TRF7970A_RX_SPECIAL_SETTINGS_AGCR       BIT(1)
 282 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_0DB     (0x0 << 2)
 283 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_5DB     (0x1 << 2)
 284 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_10DB    (0x2 << 2)
 285 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_15DB    (0x3 << 2)
 286 #define TRF7970A_RX_SPECIAL_SETTINGS_HBT        BIT(4)
 287 #define TRF7970A_RX_SPECIAL_SETTINGS_M848       BIT(5)
 288 #define TRF7970A_RX_SPECIAL_SETTINGS_C424       BIT(6)
 289 #define TRF7970A_RX_SPECIAL_SETTINGS_C212       BIT(7)
 290
 291 #define TRF7970A_REG_IO_CTRL_VRS(v)             ((v) & 0x07)
 292 #define TRF7970A_REG_IO_CTRL_IO_LOW             BIT(5)
 293 #define TRF7970A_REG_IO_CTRL_EN_EXT_PA          BIT(6)
 294 #define TRF7970A_REG_IO_CTRL_AUTO_REG           BIT(7)
 295
 296 /* IRQ Status Register Bits */
 297 #define TRF7970A_IRQ_STATUS_NORESP              BIT(0) /* ISO15693 only */
 298 #define TRF7970A_IRQ_STATUS_NFC_COL_ERROR       BIT(0)
 299 #define TRF7970A_IRQ_STATUS_COL                 BIT(1)
 300 #define TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR   BIT(2)
 301 #define TRF7970A_IRQ_STATUS_NFC_RF              BIT(2)
 302 #define TRF7970A_IRQ_STATUS_PARITY_ERROR        BIT(3)
 303 #define TRF7970A_IRQ_STATUS_NFC_SDD             BIT(3)
 304 #define TRF7970A_IRQ_STATUS_CRC_ERROR           BIT(4)
 305 #define TRF7970A_IRQ_STATUS_NFC_PROTO_ERROR     BIT(4)
 306 #define TRF7970A_IRQ_STATUS_FIFO                BIT(5)
 307 #define TRF7970A_IRQ_STATUS_SRX                 BIT(6)
 308 #define TRF7970A_IRQ_STATUS_TX                  BIT(7)
 309
 310 #define TRF7970A_IRQ_STATUS_ERROR                               \
 311                 (TRF7970A_IRQ_STATUS_COL |                      \
 312                  TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR |        \
 313                  TRF7970A_IRQ_STATUS_PARITY_ERROR |             \
 314                  TRF7970A_IRQ_STATUS_CRC_ERROR)
 315
 316 #define TRF7970A_RSSI_OSC_STATUS_RSSI_MASK      (BIT(2) | BIT(1) | BIT(0))
 317 #define TRF7970A_RSSI_OSC_STATUS_RSSI_X_MASK    (BIT(5) | BIT(4) | BIT(3))
 318 #define TRF7970A_RSSI_OSC_STATUS_RSSI_OSC_OK    BIT(6)
 319
 320 #define TRF7970A_SPECIAL_FCN_REG1_COL_7_6               BIT(0)
 321 #define TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL           BIT(1)
 322 #define TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX              BIT(2)
 323 #define TRF7970A_SPECIAL_FCN_REG1_SP_DIR_MODE           BIT(3)
 324 #define TRF7970A_SPECIAL_FCN_REG1_NEXT_SLOT_37US        BIT(4)
 325 #define TRF7970A_SPECIAL_FCN_REG1_PAR43                 BIT(5)
 326
 327 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_124      (0x0 << 2)
 328 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_120      (0x1 << 2)
 329 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_112      (0x2 << 2)
 330 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96       (0x3 << 2)
 331 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_4        0x0
 332 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_8        0x1
 333 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_16       0x2
 334 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32       0x3
 335
 336 #define TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(v)   ((v) & 0x07)
 337 #define TRF7970A_NFC_LOW_FIELD_LEVEL_CLEX_DIS   BIT(7)
 338
 339 #define TRF7970A_NFC_TARGET_LEVEL_RFDET(v)      ((v) & 0x07)
 340 #define TRF7970A_NFC_TARGET_LEVEL_HI_RF         BIT(3)
 341 #define TRF7970A_NFC_TARGET_LEVEL_SDD_EN        BIT(5)
 342 #define TRF7970A_NFC_TARGET_LEVEL_LD_S_4BYTES   (0x0 << 6)
 343 #define TRF7970A_NFC_TARGET_LEVEL_LD_S_7BYTES   (0x1 << 6)
 344 #define TRF7970A_NFC_TARGET_LEVEL_LD_S_10BYTES  (0x2 << 6)
 345
 346 #define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106         BIT(0)
 347 #define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_212         BIT(1)
 348 #define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_424         (BIT(0) | BIT(1))
 349 #define TRF79070A_NFC_TARGET_PROTOCOL_PAS_14443B        BIT(2)
 350 #define TRF79070A_NFC_TARGET_PROTOCOL_PAS_106           BIT(3)
 351 #define TRF79070A_NFC_TARGET_PROTOCOL_FELICA            BIT(4)
 352 #define TRF79070A_NFC_TARGET_PROTOCOL_RF_L              BIT(6)
 353 #define TRF79070A_NFC_TARGET_PROTOCOL_RF_H              BIT(7)
 354
 355 #define TRF79070A_NFC_TARGET_PROTOCOL_106A              \
 356          (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |          \
 357           TRF79070A_NFC_TARGET_PROTOCOL_RF_L |          \
 358           TRF79070A_NFC_TARGET_PROTOCOL_PAS_106 |       \
 359           TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106)
 360
 361 #define TRF79070A_NFC_TARGET_PROTOCOL_106B              \
 362          (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |          \
 363           TRF79070A_NFC_TARGET_PROTOCOL_RF_L |          \
 364           TRF79070A_NFC_TARGET_PROTOCOL_PAS_14443B |    \
 365           TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106)
 366
 367 #define TRF79070A_NFC_TARGET_PROTOCOL_212F              \
 368          (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |          \
 369           TRF79070A_NFC_TARGET_PROTOCOL_RF_L |          \
 370           TRF79070A_NFC_TARGET_PROTOCOL_FELICA |        \
 371           TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_212)
 372
 373 #define TRF79070A_NFC_TARGET_PROTOCOL_424F              \
 374          (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |          \
 375           TRF79070A_NFC_TARGET_PROTOCOL_RF_L |          \
 376           TRF79070A_NFC_TARGET_PROTOCOL_FELICA |        \
 377           TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_424)
 378
 379 #define TRF7970A_FIFO_STATUS_OVERFLOW           BIT(7)
 380
 381 /* NFC (ISO/IEC 14443A) Type 2 Tag commands */
 382 #define NFC_T2T_CMD_READ                        0x30
 383
 384 /* ISO 15693 commands codes */
 385 #define ISO15693_CMD_INVENTORY                  0x01
 386 #define ISO15693_CMD_READ_SINGLE_BLOCK          0x20
 387 #define ISO15693_CMD_WRITE_SINGLE_BLOCK         0x21
 388 #define ISO15693_CMD_LOCK_BLOCK                 0x22
 389 #define ISO15693_CMD_READ_MULTIPLE_BLOCK        0x23
 390 #define ISO15693_CMD_WRITE_MULTIPLE_BLOCK       0x24
 391 #define ISO15693_CMD_SELECT                     0x25
 392 #define ISO15693_CMD_RESET_TO_READY             0x26
 393 #define ISO15693_CMD_WRITE_AFI                  0x27
 394 #define ISO15693_CMD_LOCK_AFI                   0x28
 395 #define ISO15693_CMD_WRITE_DSFID                0x29
 396 #define ISO15693_CMD_LOCK_DSFID                 0x2a
 397 #define ISO15693_CMD_GET_SYSTEM_INFO            0x2b
 398 #define ISO15693_CMD_GET_MULTIPLE_BLOCK_SECURITY_STATUS 0x2c
 399
 400 /* ISO 15693 request and response flags */
 401 #define ISO15693_REQ_FLAG_SUB_CARRIER           BIT(0)
 402 #define ISO15693_REQ_FLAG_DATA_RATE             BIT(1)
 403 #define ISO15693_REQ_FLAG_INVENTORY             BIT(2)
 404 #define ISO15693_REQ_FLAG_PROTOCOL_EXT          BIT(3)
 405 #define ISO15693_REQ_FLAG_SELECT                BIT(4)
 406 #define ISO15693_REQ_FLAG_AFI                   BIT(4)
 407 #define ISO15693_REQ_FLAG_ADDRESS               BIT(5)
 408 #define ISO15693_REQ_FLAG_NB_SLOTS              BIT(5)
 409 #define ISO15693_REQ_FLAG_OPTION                BIT(6)
 410
 411 #define ISO15693_REQ_FLAG_SPEED_MASK \
 412                 (ISO15693_REQ_FLAG_SUB_CARRIER | ISO15693_REQ_FLAG_DATA_RATE)
 413
 414 enum trf7970a_state {
 415         TRF7970A_ST_PWR_OFF,
 416         TRF7970A_ST_RF_OFF,
 417         TRF7970A_ST_IDLE,
 418         TRF7970A_ST_IDLE_RX_BLOCKED,
 419         TRF7970A_ST_WAIT_FOR_TX_FIFO,
 420         TRF7970A_ST_WAIT_FOR_RX_DATA,
 421         TRF7970A_ST_WAIT_FOR_RX_DATA_CONT,
 422         TRF7970A_ST_WAIT_TO_ISSUE_EOF,
 423         TRF7970A_ST_LISTENING,
 424         TRF7970A_ST_LISTENING_MD,
 425         TRF7970A_ST_MAX
 426 };
 427
 428 struct trf7970a {
 429         enum trf7970a_state             state;
 430         struct device                   *dev;
 431         struct spi_device               *spi;
 432         struct regulator                *regulator;
 433         struct nfc_digital_dev          *ddev;
 434         u32                             quirks;
 435         bool                            is_initiator;
 436         bool                            aborting;
 437         struct sk_buff                  *tx_skb;
 438         struct sk_buff                  *rx_skb;
 439         nfc_digital_cmd_complete_t      cb;
 440         void                            *cb_arg;
 441         u8                              chip_status_ctrl;
 442         u8                              iso_ctrl;
 443         u8                              iso_ctrl_tech;
 444         u8                              modulator_sys_clk_ctrl;
 445         u8                              special_fcn_reg1;
 446         u8                              io_ctrl;
 447         unsigned int                    guard_time;
 448         int                             technology;
 449         int                             framing;
 450         u8                              md_rf_tech;
 451         u8                              tx_cmd;
 452         bool                            issue_eof;
 453         bool                            adjust_resp_len;
 454         struct gpio_desc                *en_gpiod;
 455         struct gpio_desc                *en2_gpiod;
 456         struct mutex                    lock;
 457         unsigned int                    timeout;
 458         bool                            ignore_timeout;
 459         struct delayed_work             timeout_work;
 460 };
 461
 462
 463 static int trf7970a_cmd(struct trf7970a *trf, u8 opcode)
 464 {
 465         u8 cmd = TRF7970A_CMD_BIT_CTRL | TRF7970A_CMD_BIT_OPCODE(opcode);
 466         int ret;
 467
 468         dev_dbg(trf->dev, "cmd: 0x%x\n", cmd);
 469
 470         ret = spi_write(trf->spi, &cmd, 1);
 471         if (ret)
 472                 dev_err(trf->dev, "%s - cmd: 0x%x, ret: %d\n", __func__, cmd,
 473                                 ret);
 474         return ret;
 475 }
 476
 477 static int trf7970a_read(struct trf7970a *trf, u8 reg, u8 *val)
 478 {
 479         u8 addr = TRF7970A_CMD_BIT_RW | reg;
 480         int ret;
 481
 482         ret = spi_write_then_read(trf->spi, &addr, 1, val, 1);
 483         if (ret)
 484                 dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
 485                                 ret);
 486
 487         dev_dbg(trf->dev, "read(0x%x): 0x%x\n", addr, *val);
 488
 489         return ret;
 490 }
 491
 492 static int trf7970a_read_cont(struct trf7970a *trf, u8 reg, u8 *buf, size_t len)
 493 {
 494         u8 addr = reg | TRF7970A_CMD_BIT_RW | TRF7970A_CMD_BIT_CONTINUOUS;
 495         struct spi_transfer t[2];
 496         struct spi_message m;
 497         int ret;
 498
 499         dev_dbg(trf->dev, "read_cont(0x%x, %zd)\n", addr, len);
 500
 501         spi_message_init(&m);
 502
 503         memset(&t, 0, sizeof(t));
 504
 505         t[0].tx_buf = &addr;
 506         t[0].len = sizeof(addr);
 507         spi_message_add_tail(&t[0], &m);
 508
 509         t[1].rx_buf = buf;
 510         t[1].len = len;
 511         spi_message_add_tail(&t[1], &m);
 512
 513         ret = spi_sync(trf->spi, &m);
 514         if (ret)
 515                 dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
 516                                 ret);
 517         return ret;
 518 }
 519
 520 static int trf7970a_write(struct trf7970a *trf, u8 reg, u8 val)
 521 {
 522         u8 buf[2] = { reg, val };
 523         int ret;
 524
 525         dev_dbg(trf->dev, "write(0x%x): 0x%x\n", reg, val);
 526
 527         ret = spi_write(trf->spi, buf, 2);
 528         if (ret)
 529                 dev_err(trf->dev, "%s - write: 0x%x 0x%x, ret: %d\n", __func__,
 530                                 buf[0], buf[1], ret);
 531
 532         return ret;
 533 }
 534
 535 static int trf7970a_read_irqstatus(struct trf7970a *trf, u8 *status)
 536 {
 537         int ret;
 538         u8 buf[2];
 539         u8 addr;
 540
 541         addr = TRF7970A_IRQ_STATUS | TRF7970A_CMD_BIT_RW;
 542
 543         if (trf->quirks & TRF7970A_QUIRK_IRQ_STATUS_READ) {
 544                 addr |= TRF7970A_CMD_BIT_CONTINUOUS;
 545                 ret = spi_write_then_read(trf->spi, &addr, 1, buf, 2);
 546         } else {
 547                 ret = spi_write_then_read(trf->spi, &addr, 1, buf, 1);
 548         }
 549
 550         if (ret)
 551                 dev_err(trf->dev, "%s - irqstatus: Status read failed: %d\n",
 552                                 __func__, ret);
 553         else
 554                 *status = buf[0];
 555
 556         return ret;
 557 }
 558
 559 static int trf7970a_read_target_proto(struct trf7970a *trf, u8 *target_proto)
 560 {
 561         int ret;
 562         u8 buf[2];
 563         u8 addr;
 564
 565         addr = TRF79070A_NFC_TARGET_PROTOCOL | TRF7970A_CMD_BIT_RW |
 566                 TRF7970A_CMD_BIT_CONTINUOUS;
 567
 568         ret = spi_write_then_read(trf->spi, &addr, 1, buf, 2);
 569         if (ret)
 570                 dev_err(trf->dev, "%s - target_proto: Read failed: %d\n",
 571                                 __func__, ret);
 572         else
 573                 *target_proto = buf[0];
 574
 575         return ret;
 576 }
 577
 578 static int trf7970a_mode_detect(struct trf7970a *trf, u8 *rf_tech)
 579 {
 580         int ret;
 581         u8 target_proto, tech;
 582
 583         ret = trf7970a_read_target_proto(trf, &target_proto);
 584         if (ret)
 585                 return ret;
 586
 587         switch (target_proto) {
 588         case TRF79070A_NFC_TARGET_PROTOCOL_106A:
 589                 tech = NFC_DIGITAL_RF_TECH_106A;
 590                 break;
 591         case TRF79070A_NFC_TARGET_PROTOCOL_106B:
 592                 tech = NFC_DIGITAL_RF_TECH_106B;
 593                 break;
 594         case TRF79070A_NFC_TARGET_PROTOCOL_212F:
 595                 tech = NFC_DIGITAL_RF_TECH_212F;
 596                 break;
 597         case TRF79070A_NFC_TARGET_PROTOCOL_424F:
 598                 tech = NFC_DIGITAL_RF_TECH_424F;
 599                 break;
 600         default:
 601                 dev_dbg(trf->dev, "%s - mode_detect: target_proto: 0x%x\n",
 602                                 __func__, target_proto);
 603                 return -EIO;
 604         }
 605
 606         *rf_tech = tech;
 607
 608         return ret;
 609 }
 610
 611 static void trf7970a_send_upstream(struct trf7970a *trf)
 612 {
 613         dev_kfree_skb_any(trf->tx_skb);
 614         trf->tx_skb = NULL;
 615
 616         if (trf->rx_skb && !IS_ERR(trf->rx_skb) && !trf->aborting)
 617                 print_hex_dump_debug("trf7970a rx data: ", DUMP_PREFIX_NONE,
 618                                 16, 1, trf->rx_skb->data, trf->rx_skb->len,
 619                                 false);
 620
 621         trf->state = TRF7970A_ST_IDLE;
 622
 623         if (trf->aborting) {
 624                 dev_dbg(trf->dev, "Abort process complete\n");
 625
 626                 if (!IS_ERR(trf->rx_skb)) {
 627                         kfree_skb(trf->rx_skb);
 628                         trf->rx_skb = ERR_PTR(-ECANCELED);
 629                 }
 630
 631                 trf->aborting = false;
 632         }
 633
 634         if (trf->adjust_resp_len) {
 635                 if (trf->rx_skb)
 636                         skb_trim(trf->rx_skb, trf->rx_skb->len - 1);
 637
 638                 trf->adjust_resp_len = false;
 639         }
 640
 641         trf->cb(trf->ddev, trf->cb_arg, trf->rx_skb);
 642
 643         trf->rx_skb = NULL;
 644 }
 645
 646 static void trf7970a_send_err_upstream(struct trf7970a *trf, int errno)
 647 {
 648         dev_dbg(trf->dev, "Error - state: %d, errno: %d\n", trf->state, errno);
 649
 650         cancel_delayed_work(&trf->timeout_work);
 651
 652         kfree_skb(trf->rx_skb);
 653         trf->rx_skb = ERR_PTR(errno);
 654
 655         trf7970a_send_upstream(trf);
 656 }
 657
 658 static int trf7970a_transmit(struct trf7970a *trf, struct sk_buff *skb,
 659                 unsigned int len, u8 *prefix, unsigned int prefix_len)
 660 {
 661         struct spi_transfer t[2];
 662         struct spi_message m;
 663         unsigned int timeout;
 664         int ret;
 665
 666         print_hex_dump_debug("trf7970a tx data: ", DUMP_PREFIX_NONE,
 667                         16, 1, skb->data, len, false);
 668
 669         spi_message_init(&m);
 670
 671         memset(&t, 0, sizeof(t));
 672
 673         t[0].tx_buf = prefix;
 674         t[0].len = prefix_len;
 675         spi_message_add_tail(&t[0], &m);
 676
 677         t[1].tx_buf = skb->data;
 678         t[1].len = len;
 679         spi_message_add_tail(&t[1], &m);
 680
 681         ret = spi_sync(trf->spi, &m);
 682         if (ret) {
 683                 dev_err(trf->dev, "%s - Can't send tx data: %d\n", __func__,
 684                                 ret);
 685                 return ret;
 686         }
 687
 688         skb_pull(skb, len);
 689
 690         if (skb->len > 0) {
 691                 trf->state = TRF7970A_ST_WAIT_FOR_TX_FIFO;
 692                 timeout = TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT;
 693         } else {
 694                 if (trf->issue_eof) {
 695                         trf->state = TRF7970A_ST_WAIT_TO_ISSUE_EOF;
 696                         timeout = TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF;
 697                 } else {
 698                         trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
 699
 700                         if (!trf->timeout)
 701                                 timeout = TRF7970A_WAIT_FOR_TX_IRQ;
 702                         else
 703                                 timeout = trf->timeout;
 704                 }
 705         }
 706
 707         dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n", timeout,
 708                         trf->state);
 709
 710         schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
 711
 712         return 0;
 713 }
 714
 715 static void trf7970a_fill_fifo(struct trf7970a *trf)
 716 {
 717         struct sk_buff *skb = trf->tx_skb;
 718         unsigned int len;
 719         int ret;
 720         u8 fifo_bytes;
 721         u8 prefix;
 722
 723         ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
 724         if (ret) {
 725                 trf7970a_send_err_upstream(trf, ret);
 726                 return;
 727         }
 728
 729         dev_dbg(trf->dev, "Filling FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
 730
 731         fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
 732
 733         /* Calculate how much more data can be written to the fifo */
 734         len = TRF7970A_FIFO_SIZE - fifo_bytes;
 735         if (!len) {
 736                 schedule_delayed_work(&trf->timeout_work,
 737                         msecs_to_jiffies(TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT));
 738                 return;
 739         }
 740
 741         len = min(skb->len, len);
 742
 743         prefix = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_FIFO_IO_REGISTER;
 744
 745         ret = trf7970a_transmit(trf, skb, len, &prefix, sizeof(prefix));
 746         if (ret)
 747                 trf7970a_send_err_upstream(trf, ret);
 748 }
 749
 750 static void trf7970a_drain_fifo(struct trf7970a *trf, u8 status)
 751 {
 752         struct sk_buff *skb = trf->rx_skb;
 753         int ret;
 754         u8 fifo_bytes;
 755
 756         if (status & TRF7970A_IRQ_STATUS_ERROR) {
 757                 trf7970a_send_err_upstream(trf, -EIO);
 758                 return;
 759         }
 760
 761         ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
 762         if (ret) {
 763                 trf7970a_send_err_upstream(trf, ret);
 764                 return;
 765         }
 766
 767         dev_dbg(trf->dev, "Draining FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
 768
 769         fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
 770
 771         if (!fifo_bytes)
 772                 goto no_rx_data;
 773
 774         if (fifo_bytes > skb_tailroom(skb)) {
 775                 skb = skb_copy_expand(skb, skb_headroom(skb),
 776                                 max_t(int, fifo_bytes,
 777                                         TRF7970A_RX_SKB_ALLOC_SIZE),
 778                                 GFP_KERNEL);
 779                 if (!skb) {
 780                         trf7970a_send_err_upstream(trf, -ENOMEM);
 781                         return;
 782                 }
 783
 784                 kfree_skb(trf->rx_skb);
 785                 trf->rx_skb = skb;
 786         }
 787
 788         ret = trf7970a_read_cont(trf, TRF7970A_FIFO_IO_REGISTER,
 789                         skb_put(skb, fifo_bytes), fifo_bytes);
 790         if (ret) {
 791                 trf7970a_send_err_upstream(trf, ret);
 792                 return;
 793         }
 794
 795         /* If received Type 2 ACK/NACK, shift right 4 bits and pass up */
 796         if ((trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T) && (skb->len == 1) &&
 797                         (trf->special_fcn_reg1 ==
 798                                  TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX)) {
 799                 skb->data[0] >>= 4;
 800                 status = TRF7970A_IRQ_STATUS_SRX;
 801         } else {
 802                 trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA_CONT;
 803
 804                 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
 805                 if (ret) {
 806                         trf7970a_send_err_upstream(trf, ret);
 807                         return;
 808                 }
 809
 810                 fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
 811
 812                 /* If there are bytes in the FIFO, set status to '0' so
 813                  * the if stmt below doesn't fire and the driver will wait
 814                  * for the trf7970a to generate another RX interrupt.
 815                  */
 816                 if (fifo_bytes)
 817                         status = 0;
 818         }
 819
 820 no_rx_data:
 821         if (status == TRF7970A_IRQ_STATUS_SRX) { /* Receive complete */
 822                 trf7970a_send_upstream(trf);
 823                 return;
 824         }
 825
 826         dev_dbg(trf->dev, "Setting timeout for %d ms\n",
 827                         TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT);
 828
 829         schedule_delayed_work(&trf->timeout_work,
 830                         msecs_to_jiffies(TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT));
 831 }
 832
 833 static irqreturn_t trf7970a_irq(int irq, void *dev_id)
 834 {
 835         struct trf7970a *trf = dev_id;
 836         int ret;
 837         u8 status, fifo_bytes, iso_ctrl;
 838
 839         mutex_lock(&trf->lock);
 840
 841         if (trf->state == TRF7970A_ST_RF_OFF) {
 842                 mutex_unlock(&trf->lock);
 843                 return IRQ_NONE;
 844         }
 845
 846         ret = trf7970a_read_irqstatus(trf, &status);
 847         if (ret) {
 848                 mutex_unlock(&trf->lock);
 849                 return IRQ_NONE;
 850         }
 851
 852         dev_dbg(trf->dev, "IRQ - state: %d, status: 0x%x\n", trf->state,
 853                         status);
 854
 855         if (!status) {
 856                 mutex_unlock(&trf->lock);
 857                 return IRQ_NONE;
 858         }
 859
 860         switch (trf->state) {
 861         case TRF7970A_ST_IDLE:
 862         case TRF7970A_ST_IDLE_RX_BLOCKED:
 863                 /* If initiator and getting interrupts caused by RF noise,
 864                  * turn off the receiver to avoid unnecessary interrupts.
 865                  * It will be turned back on in trf7970a_send_cmd() when
 866                  * the next command is issued.
 867                  */
 868                 if (trf->is_initiator && (status & TRF7970A_IRQ_STATUS_ERROR)) {
 869                         trf7970a_cmd(trf, TRF7970A_CMD_BLOCK_RX);
 870                         trf->state = TRF7970A_ST_IDLE_RX_BLOCKED;
 871                 }
 872
 873                 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
 874                 break;
 875         case TRF7970A_ST_WAIT_FOR_TX_FIFO:
 876                 if (status & TRF7970A_IRQ_STATUS_TX) {
 877                         trf->ignore_timeout =
 878                                 !cancel_delayed_work(&trf->timeout_work);
 879                         trf7970a_fill_fifo(trf);
 880                 } else {
 881                         trf7970a_send_err_upstream(trf, -EIO);
 882                 }
 883                 break;
 884         case TRF7970A_ST_WAIT_FOR_RX_DATA:
 885         case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
 886                 if (status & TRF7970A_IRQ_STATUS_SRX) {
 887                         trf->ignore_timeout =
 888                                 !cancel_delayed_work(&trf->timeout_work);
 889                         trf7970a_drain_fifo(trf, status);
 890                 } else if (status & TRF7970A_IRQ_STATUS_FIFO) {
 891                         ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS,
 892                                         &fifo_bytes);
 893
 894                         fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
 895
 896                         if (ret)
 897                                 trf7970a_send_err_upstream(trf, ret);
 898                         else if (!fifo_bytes)
 899                                 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
 900                 } else if ((status == TRF7970A_IRQ_STATUS_TX) ||
 901                                 (!trf->is_initiator &&
 902                                  (status == (TRF7970A_IRQ_STATUS_TX |
 903                                              TRF7970A_IRQ_STATUS_NFC_RF)))) {
 904                         trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
 905
 906                         if (!trf->timeout) {
 907                                 trf->ignore_timeout = !cancel_delayed_work(
 908                                                 &trf->timeout_work);
 909                                 trf->rx_skb = ERR_PTR(0);
 910                                 trf7970a_send_upstream(trf);
 911                                 break;
 912                         }
 913
 914                         if (trf->is_initiator)
 915                                 break;
 916
 917                         iso_ctrl = trf->iso_ctrl;
 918
 919                         switch (trf->framing) {
 920                         case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
 921                                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
 922                                 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
 923                                 trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
 924                                 break;
 925                         case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
 926                                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
 927                                 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
 928                                 trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
 929                                 break;
 930                         case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
 931                                 ret = trf7970a_write(trf,
 932                                         TRF7970A_SPECIAL_FCN_REG1,
 933                                         TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL);
 934                                 if (ret)
 935                                         goto err_unlock_exit;
 936
 937                                 trf->special_fcn_reg1 =
 938                                         TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL;
 939                                 break;
 940                         default:
 941                                 break;
 942                         }
 943
 944                         if (iso_ctrl != trf->iso_ctrl) {
 945                                 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
 946                                                 iso_ctrl);
 947                                 if (ret)
 948                                         goto err_unlock_exit;
 949
 950                                 trf->iso_ctrl = iso_ctrl;
 951                         }
 952                 } else {
 953                         trf7970a_send_err_upstream(trf, -EIO);
 954                 }
 955                 break;
 956         case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
 957                 if (status != TRF7970A_IRQ_STATUS_TX)
 958                         trf7970a_send_err_upstream(trf, -EIO);
 959                 break;
 960         case TRF7970A_ST_LISTENING:
 961                 if (status & TRF7970A_IRQ_STATUS_SRX) {
 962                         trf->ignore_timeout =
 963                                 !cancel_delayed_work(&trf->timeout_work);
 964                         trf7970a_drain_fifo(trf, status);
 965                 } else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
 966                         trf7970a_send_err_upstream(trf, -EIO);
 967                 }
 968                 break;
 969         case TRF7970A_ST_LISTENING_MD:
 970                 if (status & TRF7970A_IRQ_STATUS_SRX) {
 971                         trf->ignore_timeout =
 972                                 !cancel_delayed_work(&trf->timeout_work);
 973
 974                         ret = trf7970a_mode_detect(trf, &trf->md_rf_tech);
 975                         if (ret) {
 976                                 trf7970a_send_err_upstream(trf, ret);
 977                         } else {
 978                                 trf->state = TRF7970A_ST_LISTENING;
 979                                 trf7970a_drain_fifo(trf, status);
 980                         }
 981                 } else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
 982                         trf7970a_send_err_upstream(trf, -EIO);
 983                 }
 984                 break;
 985         default:
 986                 dev_err(trf->dev, "%s - Driver in invalid state: %d\n",
 987                                 __func__, trf->state);
 988         }
 989
 990 err_unlock_exit:
 991         mutex_unlock(&trf->lock);
 992         return IRQ_HANDLED;
 993 }
 994
 995 static void trf7970a_issue_eof(struct trf7970a *trf)
 996 {
 997         int ret;
 998
 999         dev_dbg(trf->dev, "Issuing EOF\n");
1000
1001         ret = trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
1002         if (ret)
1003                 trf7970a_send_err_upstream(trf, ret);
1004
1005         ret = trf7970a_cmd(trf, TRF7970A_CMD_EOF);
1006         if (ret)
1007                 trf7970a_send_err_upstream(trf, ret);
1008
1009         trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
1010
1011         dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n",
1012                         trf->timeout, trf->state);
1013
1014         schedule_delayed_work(&trf->timeout_work,
1015                         msecs_to_jiffies(trf->timeout));
1016 }
1017
1018 static void trf7970a_timeout_work_handler(struct work_struct *work)
1019 {
1020         struct trf7970a *trf = container_of(work, struct trf7970a,
1021                         timeout_work.work);
1022
1023         dev_dbg(trf->dev, "Timeout - state: %d, ignore_timeout: %d\n",
1024                         trf->state, trf->ignore_timeout);
1025
1026         mutex_lock(&trf->lock);
1027
1028         if (trf->ignore_timeout)
1029                 trf->ignore_timeout = false;
1030         else if (trf->state == TRF7970A_ST_WAIT_FOR_RX_DATA_CONT)
1031                 trf7970a_drain_fifo(trf, TRF7970A_IRQ_STATUS_SRX);
1032         else if (trf->state == TRF7970A_ST_WAIT_TO_ISSUE_EOF)
1033                 trf7970a_issue_eof(trf);
1034         else
1035                 trf7970a_send_err_upstream(trf, -ETIMEDOUT);
1036
1037         mutex_unlock(&trf->lock);
1038 }
1039
1040 static int trf7970a_init(struct trf7970a *trf)
1041 {
1042         int ret;
1043
1044         dev_dbg(trf->dev, "Initializing device - state: %d\n", trf->state);
1045
1046         ret = trf7970a_cmd(trf, TRF7970A_CMD_SOFT_INIT);
1047         if (ret)
1048                 goto err_out;
1049
1050         ret = trf7970a_cmd(trf, TRF7970A_CMD_IDLE);
1051         if (ret)
1052                 goto err_out;
1053
1054         ret = trf7970a_write(trf, TRF7970A_REG_IO_CTRL,
1055                         trf->io_ctrl | TRF7970A_REG_IO_CTRL_VRS(0x1));
1056         if (ret)
1057                 goto err_out;
1058
1059         ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, 0);
1060         if (ret)
1061                 goto err_out;
1062
1063         usleep_range(1000, 2000);
1064
1065         trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1066
1067         ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1068                         trf->modulator_sys_clk_ctrl);
1069         if (ret)
1070                 goto err_out;
1071
1072         ret = trf7970a_write(trf, TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS,
1073                         TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 |
1074                         TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32);
1075         if (ret)
1076                 goto err_out;
1077
1078         ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1, 0);
1079         if (ret)
1080                 goto err_out;
1081
1082         trf->special_fcn_reg1 = 0;
1083
1084         trf->iso_ctrl = 0xff;
1085         return 0;
1086
1087 err_out:
1088         dev_dbg(trf->dev, "Couldn't init device: %d\n", ret);
1089         return ret;
1090 }
1091
1092 static void trf7970a_switch_rf_off(struct trf7970a *trf)
1093 {
1094         if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1095                         (trf->state == TRF7970A_ST_RF_OFF))
1096                 return;
1097
1098         dev_dbg(trf->dev, "Switching rf off\n");
1099
1100         trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1101
1102         trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL, trf->chip_status_ctrl);
1103
1104         trf->aborting = false;
1105         trf->state = TRF7970A_ST_RF_OFF;
1106
1107         pm_runtime_mark_last_busy(trf->dev);
1108         pm_runtime_put_autosuspend(trf->dev);
1109 }
1110
1111 static int trf7970a_switch_rf_on(struct trf7970a *trf)
1112 {
1113         int ret;
1114
1115         dev_dbg(trf->dev, "Switching rf on\n");
1116
1117         pm_runtime_get_sync(trf->dev);
1118
1119         if (trf->state != TRF7970A_ST_RF_OFF) { /* Power on, RF off */
1120                 dev_err(trf->dev, "%s - Incorrect state: %d\n", __func__,
1121                                 trf->state);
1122                 return -EINVAL;
1123         }
1124
1125         ret = trf7970a_init(trf);
1126         if (ret) {
1127                 dev_err(trf->dev, "%s - Can't initialize: %d\n", __func__, ret);
1128                 return ret;
1129         }
1130
1131         trf->state = TRF7970A_ST_IDLE;
1132
1133         return 0;
1134 }
1135
1136 static int trf7970a_switch_rf(struct nfc_digital_dev *ddev, bool on)
1137 {
1138         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1139         int ret = 0;
1140
1141         dev_dbg(trf->dev, "Switching RF - state: %d, on: %d\n", trf->state, on);
1142
1143         mutex_lock(&trf->lock);
1144
1145         if (on) {
1146                 switch (trf->state) {
1147                 case TRF7970A_ST_PWR_OFF:
1148                 case TRF7970A_ST_RF_OFF:
1149                         ret = trf7970a_switch_rf_on(trf);
1150                         break;
1151                 case TRF7970A_ST_IDLE:
1152                 case TRF7970A_ST_IDLE_RX_BLOCKED:
1153                         break;
1154                 default:
1155                         dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1156                                         __func__, trf->state, on);
1157                         trf7970a_switch_rf_off(trf);
1158                         ret = -EINVAL;
1159                 }
1160         } else {
1161                 switch (trf->state) {
1162                 case TRF7970A_ST_PWR_OFF:
1163                 case TRF7970A_ST_RF_OFF:
1164                         break;
1165                 default:
1166                         dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1167                                         __func__, trf->state, on);
1168                         ret = -EINVAL;
1169                         /* FALLTHROUGH */
1170                 case TRF7970A_ST_IDLE:
1171                 case TRF7970A_ST_IDLE_RX_BLOCKED:
1172                 case TRF7970A_ST_WAIT_FOR_RX_DATA:
1173                 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1174                         trf7970a_switch_rf_off(trf);
1175                 }
1176         }
1177
1178         mutex_unlock(&trf->lock);
1179         return ret;
1180 }
1181
1182 static int trf7970a_in_config_rf_tech(struct trf7970a *trf, int tech)
1183 {
1184         int ret = 0;
1185
1186         dev_dbg(trf->dev, "rf technology: %d\n", tech);
1187
1188         switch (tech) {
1189         case NFC_DIGITAL_RF_TECH_106A:
1190                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443A_106;
1191                 trf->modulator_sys_clk_ctrl =
1192                         (trf->modulator_sys_clk_ctrl & 0xf8) |
1193                         TRF7970A_MODULATOR_DEPTH_OOK;
1194                 trf->guard_time = TRF7970A_GUARD_TIME_NFCA;
1195                 break;
1196         case NFC_DIGITAL_RF_TECH_106B:
1197                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443B_106;
1198                 trf->modulator_sys_clk_ctrl =
1199                         (trf->modulator_sys_clk_ctrl & 0xf8) |
1200                         TRF7970A_MODULATOR_DEPTH_ASK10;
1201                 trf->guard_time = TRF7970A_GUARD_TIME_NFCB;
1202                 break;
1203         case NFC_DIGITAL_RF_TECH_212F:
1204                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_212;
1205                 trf->modulator_sys_clk_ctrl =
1206                         (trf->modulator_sys_clk_ctrl & 0xf8) |
1207                         TRF7970A_MODULATOR_DEPTH_ASK10;
1208                 trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1209                 break;
1210         case NFC_DIGITAL_RF_TECH_424F:
1211                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_424;
1212                 trf->modulator_sys_clk_ctrl =
1213                         (trf->modulator_sys_clk_ctrl & 0xf8) |
1214                         TRF7970A_MODULATOR_DEPTH_ASK10;
1215                 trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1216                 break;
1217         case NFC_DIGITAL_RF_TECH_ISO15693:
1218                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1219                 trf->modulator_sys_clk_ctrl =
1220                         (trf->modulator_sys_clk_ctrl & 0xf8) |
1221                         TRF7970A_MODULATOR_DEPTH_OOK;
1222                 trf->guard_time = TRF7970A_GUARD_TIME_15693;
1223                 break;
1224         default:
1225                 dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1226                 return -EINVAL;
1227         }
1228
1229         trf->technology = tech;
1230
1231         /* If in initiator mode and not changing the RF tech due to a
1232          * PSL sequence (indicated by 'trf->iso_ctrl == 0xff' from
1233          * trf7970a_init()), clear the NFC Target Detection Level register
1234          * due to erratum.
1235          */
1236         if (trf->iso_ctrl == 0xff)
1237                 ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, 0);
1238
1239         return ret;
1240 }
1241
1242 static int trf7970a_is_rf_field(struct trf7970a *trf, bool *is_rf_field)
1243 {
1244         int ret;
1245         u8 rssi;
1246
1247         ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1248                         trf->chip_status_ctrl | TRF7970A_CHIP_STATUS_REC_ON);
1249         if (ret)
1250                 return ret;
1251
1252         ret = trf7970a_cmd(trf, TRF7970A_CMD_TEST_EXT_RF);
1253         if (ret)
1254                 return ret;
1255
1256         usleep_range(50, 60);
1257
1258         ret = trf7970a_read(trf, TRF7970A_RSSI_OSC_STATUS, &rssi);
1259         if (ret)
1260                 return ret;
1261
1262         ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1263                         trf->chip_status_ctrl);
1264         if (ret)
1265                 return ret;
1266
1267         if (rssi & TRF7970A_RSSI_OSC_STATUS_RSSI_MASK)
1268                 *is_rf_field = true;
1269         else
1270                 *is_rf_field = false;
1271
1272         return 0;
1273 }
1274
1275 static int trf7970a_in_config_framing(struct trf7970a *trf, int framing)
1276 {
1277         u8 iso_ctrl = trf->iso_ctrl_tech;
1278         bool is_rf_field = false;
1279         int ret;
1280
1281         dev_dbg(trf->dev, "framing: %d\n", framing);
1282
1283         switch (framing) {
1284         case NFC_DIGITAL_FRAMING_NFCA_SHORT:
1285         case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1286                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1287                 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1288                 break;
1289         case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1290         case NFC_DIGITAL_FRAMING_NFCA_T4T:
1291         case NFC_DIGITAL_FRAMING_NFCB:
1292         case NFC_DIGITAL_FRAMING_NFCB_T4T:
1293         case NFC_DIGITAL_FRAMING_NFCF:
1294         case NFC_DIGITAL_FRAMING_NFCF_T3T:
1295         case NFC_DIGITAL_FRAMING_ISO15693_INVENTORY:
1296         case NFC_DIGITAL_FRAMING_ISO15693_T5T:
1297         case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1298         case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1299                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1300                 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1301                 break;
1302         case NFC_DIGITAL_FRAMING_NFCA_T2T:
1303                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1304                 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1305                 break;
1306         default:
1307                 dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1308                 return -EINVAL;
1309         }
1310
1311         trf->framing = framing;
1312
1313         if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1314                 ret = trf7970a_is_rf_field(trf, &is_rf_field);
1315                 if (ret)
1316                         return ret;
1317
1318                 if (is_rf_field)
1319                         return -EBUSY;
1320         }
1321
1322         if (iso_ctrl != trf->iso_ctrl) {
1323                 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1324                 if (ret)
1325                         return ret;
1326
1327                 trf->iso_ctrl = iso_ctrl;
1328
1329                 ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1330                                 trf->modulator_sys_clk_ctrl);
1331                 if (ret)
1332                         return ret;
1333         }
1334
1335         if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1336                 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1337                                 trf->chip_status_ctrl |
1338                                         TRF7970A_CHIP_STATUS_RF_ON);
1339                 if (ret)
1340                         return ret;
1341
1342                 trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1343
1344                 usleep_range(trf->guard_time, trf->guard_time + 1000);
1345         }
1346
1347         return 0;
1348 }
1349
1350 static int trf7970a_in_configure_hw(struct nfc_digital_dev *ddev, int type,
1351                 int param)
1352 {
1353         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1354         int ret;
1355
1356         dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1357
1358         mutex_lock(&trf->lock);
1359
1360         trf->is_initiator = true;
1361
1362         if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1363                         (trf->state == TRF7970A_ST_RF_OFF)) {
1364                 ret = trf7970a_switch_rf_on(trf);
1365                 if (ret)
1366                         goto err_unlock;
1367         }
1368
1369         switch (type) {
1370         case NFC_DIGITAL_CONFIG_RF_TECH:
1371                 ret = trf7970a_in_config_rf_tech(trf, param);
1372                 break;
1373         case NFC_DIGITAL_CONFIG_FRAMING:
1374                 ret = trf7970a_in_config_framing(trf, param);
1375                 break;
1376         default:
1377                 dev_dbg(trf->dev, "Unknown type: %d\n", type);
1378                 ret = -EINVAL;
1379         }
1380
1381 err_unlock:
1382         mutex_unlock(&trf->lock);
1383         return ret;
1384 }
1385
1386 static int trf7970a_is_iso15693_write_or_lock(u8 cmd)
1387 {
1388         switch (cmd) {
1389         case ISO15693_CMD_WRITE_SINGLE_BLOCK:
1390         case ISO15693_CMD_LOCK_BLOCK:
1391         case ISO15693_CMD_WRITE_MULTIPLE_BLOCK:
1392         case ISO15693_CMD_WRITE_AFI:
1393         case ISO15693_CMD_LOCK_AFI:
1394         case ISO15693_CMD_WRITE_DSFID:
1395         case ISO15693_CMD_LOCK_DSFID:
1396                 return 1;
1397                 break;
1398         default:
1399                 return 0;
1400         }
1401 }
1402
1403 static int trf7970a_per_cmd_config(struct trf7970a *trf, struct sk_buff *skb)
1404 {
1405         u8 *req = skb->data;
1406         u8 special_fcn_reg1, iso_ctrl;
1407         int ret;
1408
1409         trf->issue_eof = false;
1410
1411         /* When issuing Type 2 read command, make sure the '4_bit_RX' bit in
1412          * special functions register 1 is cleared; otherwise, its a write or
1413          * sector select command and '4_bit_RX' must be set.
1414          *
1415          * When issuing an ISO 15693 command, inspect the flags byte to see
1416          * what speed to use.  Also, remember if the OPTION flag is set on
1417          * a Type 5 write or lock command so the driver will know that it
1418          * has to send an EOF in order to get a response.
1419          */
1420         if ((trf->technology == NFC_DIGITAL_RF_TECH_106A) &&
1421                         (trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T)) {
1422                 if (req[0] == NFC_T2T_CMD_READ)
1423                         special_fcn_reg1 = 0;
1424                 else
1425                         special_fcn_reg1 = TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX;
1426
1427                 if (special_fcn_reg1 != trf->special_fcn_reg1) {
1428                         ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1,
1429                                         special_fcn_reg1);
1430                         if (ret)
1431                                 return ret;
1432
1433                         trf->special_fcn_reg1 = special_fcn_reg1;
1434                 }
1435         } else if (trf->technology == NFC_DIGITAL_RF_TECH_ISO15693) {
1436                 iso_ctrl = trf->iso_ctrl & ~TRF7970A_ISO_CTRL_RFID_SPEED_MASK;
1437
1438                 switch (req[0] & ISO15693_REQ_FLAG_SPEED_MASK) {
1439                 case 0x00:
1440                         iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_662;
1441                         break;
1442                 case ISO15693_REQ_FLAG_SUB_CARRIER:
1443                         iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a;
1444                         break;
1445                 case ISO15693_REQ_FLAG_DATA_RATE:
1446                         iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1447                         break;
1448                 case (ISO15693_REQ_FLAG_SUB_CARRIER |
1449                                 ISO15693_REQ_FLAG_DATA_RATE):
1450                         iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669;
1451                         break;
1452                 }
1453
1454                 if (iso_ctrl != trf->iso_ctrl) {
1455                         ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1456                         if (ret)
1457                                 return ret;
1458
1459                         trf->iso_ctrl = iso_ctrl;
1460                 }
1461
1462                 if (trf->framing == NFC_DIGITAL_FRAMING_ISO15693_T5T) {
1463                         if (trf7970a_is_iso15693_write_or_lock(req[1]) &&
1464                                         (req[0] & ISO15693_REQ_FLAG_OPTION))
1465                                 trf->issue_eof = true;
1466                         else if ((trf->quirks &
1467                                         TRF7970A_QUIRK_T5T_RMB_EXTRA_BYTE) &&
1468                                  (req[1] == ISO15693_CMD_READ_MULTIPLE_BLOCK))
1469                                 trf->adjust_resp_len = true;
1470                 }
1471         }
1472
1473         return 0;
1474 }
1475
1476 static int trf7970a_send_cmd(struct nfc_digital_dev *ddev,
1477                 struct sk_buff *skb, u16 timeout,
1478                 nfc_digital_cmd_complete_t cb, void *arg)
1479 {
1480         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1481         u8 prefix[5];
1482         unsigned int len;
1483         int ret;
1484         u8 status;
1485
1486         dev_dbg(trf->dev, "New request - state: %d, timeout: %d ms, len: %d\n",
1487                         trf->state, timeout, skb->len);
1488
1489         if (skb->len > TRF7970A_TX_MAX)
1490                 return -EINVAL;
1491
1492         mutex_lock(&trf->lock);
1493
1494         if ((trf->state != TRF7970A_ST_IDLE) &&
1495                         (trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1496                 dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1497                                 trf->state);
1498                 ret = -EIO;
1499                 goto out_err;
1500         }
1501
1502         if (trf->aborting) {
1503                 dev_dbg(trf->dev, "Abort process complete\n");
1504                 trf->aborting = false;
1505                 ret = -ECANCELED;
1506                 goto out_err;
1507         }
1508
1509         if (timeout) {
1510                 trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1511                                 GFP_KERNEL);
1512                 if (!trf->rx_skb) {
1513                         dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1514                         ret = -ENOMEM;
1515                         goto out_err;
1516                 }
1517         }
1518
1519         if (trf->state == TRF7970A_ST_IDLE_RX_BLOCKED) {
1520                 ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1521                 if (ret)
1522                         goto out_err;
1523
1524                 trf->state = TRF7970A_ST_IDLE;
1525         }
1526
1527         if (trf->is_initiator) {
1528                 ret = trf7970a_per_cmd_config(trf, skb);
1529                 if (ret)
1530                         goto out_err;
1531         }
1532
1533         trf->ddev = ddev;
1534         trf->tx_skb = skb;
1535         trf->cb = cb;
1536         trf->cb_arg = arg;
1537         trf->timeout = timeout;
1538         trf->ignore_timeout = false;
1539
1540         len = skb->len;
1541
1542         /* TX data must be prefixed with a FIFO reset cmd, a cmd that depends
1543          * on what the current framing is, the address of the TX length byte 1
1544          * register (0x1d), and the 2 byte length of the data to be transmitted.
1545          * That totals 5 bytes.
1546          */
1547         prefix[0] = TRF7970A_CMD_BIT_CTRL |
1548                         TRF7970A_CMD_BIT_OPCODE(TRF7970A_CMD_FIFO_RESET);
1549         prefix[1] = TRF7970A_CMD_BIT_CTRL |
1550                         TRF7970A_CMD_BIT_OPCODE(trf->tx_cmd);
1551         prefix[2] = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_TX_LENGTH_BYTE1;
1552
1553         if (trf->framing == NFC_DIGITAL_FRAMING_NFCA_SHORT) {
1554                 prefix[3] = 0x00;
1555                 prefix[4] = 0x0f; /* 7 bits */
1556         } else {
1557                 prefix[3] = (len & 0xf00) >> 4;
1558                 prefix[3] |= ((len & 0xf0) >> 4);
1559                 prefix[4] = ((len & 0x0f) << 4);
1560         }
1561
1562         len = min_t(int, skb->len, TRF7970A_FIFO_SIZE);
1563
1564         /* Clear possible spurious interrupt */
1565         ret = trf7970a_read_irqstatus(trf, &status);
1566         if (ret)
1567                 goto out_err;
1568
1569         ret = trf7970a_transmit(trf, skb, len, prefix, sizeof(prefix));
1570         if (ret) {
1571                 kfree_skb(trf->rx_skb);
1572                 trf->rx_skb = NULL;
1573         }
1574
1575 out_err:
1576         mutex_unlock(&trf->lock);
1577         return ret;
1578 }
1579
1580 static int trf7970a_tg_config_rf_tech(struct trf7970a *trf, int tech)
1581 {
1582         int ret = 0;
1583
1584         dev_dbg(trf->dev, "rf technology: %d\n", tech);
1585
1586         switch (tech) {
1587         case NFC_DIGITAL_RF_TECH_106A:
1588                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1589                         TRF7970A_ISO_CTRL_NFC_CE |
1590                         TRF7970A_ISO_CTRL_NFC_CE_14443A;
1591                 trf->modulator_sys_clk_ctrl =
1592                         (trf->modulator_sys_clk_ctrl & 0xf8) |
1593                         TRF7970A_MODULATOR_DEPTH_OOK;
1594                 break;
1595         case NFC_DIGITAL_RF_TECH_212F:
1596                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1597                         TRF7970A_ISO_CTRL_NFC_NFCF_212;
1598                 trf->modulator_sys_clk_ctrl =
1599                         (trf->modulator_sys_clk_ctrl & 0xf8) |
1600                         TRF7970A_MODULATOR_DEPTH_ASK10;
1601                 break;
1602         case NFC_DIGITAL_RF_TECH_424F:
1603                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1604                         TRF7970A_ISO_CTRL_NFC_NFCF_424;
1605                 trf->modulator_sys_clk_ctrl =
1606                         (trf->modulator_sys_clk_ctrl & 0xf8) |
1607                         TRF7970A_MODULATOR_DEPTH_ASK10;
1608                 break;
1609         default:
1610                 dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1611                 return -EINVAL;
1612         }
1613
1614         trf->technology = tech;
1615
1616         /* Normally we write the ISO_CTRL register in
1617          * trf7970a_tg_config_framing() because the framing can change
1618          * the value written.  However, when sending a PSL RES,
1619          * digital_tg_send_psl_res_complete() doesn't call
1620          * trf7970a_tg_config_framing() so we must write the register
1621          * here.
1622          */
1623         if ((trf->framing == NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED) &&
1624                         (trf->iso_ctrl_tech != trf->iso_ctrl)) {
1625                 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
1626                                 trf->iso_ctrl_tech);
1627
1628                 trf->iso_ctrl = trf->iso_ctrl_tech;
1629         }
1630
1631         return ret;
1632 }
1633
1634 /* Since this is a target routine, several of the framing calls are
1635  * made between receiving the request and sending the response so they
1636  * should take effect until after the response is sent.  This is accomplished
1637  * by skipping the ISO_CTRL register write here and doing it in the interrupt
1638  * handler.
1639  */
1640 static int trf7970a_tg_config_framing(struct trf7970a *trf, int framing)
1641 {
1642         u8 iso_ctrl = trf->iso_ctrl_tech;
1643         int ret;
1644
1645         dev_dbg(trf->dev, "framing: %d\n", framing);
1646
1647         switch (framing) {
1648         case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1649                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1650                 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1651                 break;
1652         case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1653         case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1654         case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
1655                 /* These ones are applied in the interrupt handler */
1656                 iso_ctrl = trf->iso_ctrl; /* Don't write to ISO_CTRL yet */
1657                 break;
1658         case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1659                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1660                 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1661                 break;
1662         case NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED:
1663                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1664                 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1665                 break;
1666         default:
1667                 dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1668                 return -EINVAL;
1669         }
1670
1671         trf->framing = framing;
1672
1673         if (iso_ctrl != trf->iso_ctrl) {
1674                 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1675                 if (ret)
1676                         return ret;
1677
1678                 trf->iso_ctrl = iso_ctrl;
1679
1680                 ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1681                                 trf->modulator_sys_clk_ctrl);
1682                 if (ret)
1683                         return ret;
1684         }
1685
1686         if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1687                 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1688                                 trf->chip_status_ctrl |
1689                                         TRF7970A_CHIP_STATUS_RF_ON);
1690                 if (ret)
1691                         return ret;
1692
1693                 trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1694         }
1695
1696         return 0;
1697 }
1698
1699 static int trf7970a_tg_configure_hw(struct nfc_digital_dev *ddev, int type,
1700                 int param)
1701 {
1702         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1703         int ret;
1704
1705         dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1706
1707         mutex_lock(&trf->lock);
1708
1709         trf->is_initiator = false;
1710
1711         if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1712                         (trf->state == TRF7970A_ST_RF_OFF)) {
1713                 ret = trf7970a_switch_rf_on(trf);
1714                 if (ret)
1715                         goto err_unlock;
1716         }
1717
1718         switch (type) {
1719         case NFC_DIGITAL_CONFIG_RF_TECH:
1720                 ret = trf7970a_tg_config_rf_tech(trf, param);
1721                 break;
1722         case NFC_DIGITAL_CONFIG_FRAMING:
1723                 ret = trf7970a_tg_config_framing(trf, param);
1724                 break;
1725         default:
1726                 dev_dbg(trf->dev, "Unknown type: %d\n", type);
1727                 ret = -EINVAL;
1728         }
1729
1730 err_unlock:
1731         mutex_unlock(&trf->lock);
1732         return ret;
1733 }
1734
1735 static int _trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1736                 nfc_digital_cmd_complete_t cb, void *arg, bool mode_detect)
1737 {
1738         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1739         int ret;
1740
1741         mutex_lock(&trf->lock);
1742
1743         if ((trf->state != TRF7970A_ST_IDLE) &&
1744                         (trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1745                 dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1746                                 trf->state);
1747                 ret = -EIO;
1748                 goto out_err;
1749         }
1750
1751         if (trf->aborting) {
1752                 dev_dbg(trf->dev, "Abort process complete\n");
1753                 trf->aborting = false;
1754                 ret = -ECANCELED;
1755                 goto out_err;
1756         }
1757
1758         trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1759                         GFP_KERNEL);
1760         if (!trf->rx_skb) {
1761                 dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1762                 ret = -ENOMEM;
1763                 goto out_err;
1764         }
1765
1766         ret = trf7970a_write(trf, TRF7970A_RX_SPECIAL_SETTINGS,
1767                         TRF7970A_RX_SPECIAL_SETTINGS_HBT |
1768                         TRF7970A_RX_SPECIAL_SETTINGS_M848 |
1769                         TRF7970A_RX_SPECIAL_SETTINGS_C424 |
1770                         TRF7970A_RX_SPECIAL_SETTINGS_C212);
1771         if (ret)
1772                 goto out_err;
1773
1774         ret = trf7970a_write(trf, TRF7970A_REG_IO_CTRL,
1775                         trf->io_ctrl | TRF7970A_REG_IO_CTRL_VRS(0x1));
1776         if (ret)
1777                 goto out_err;
1778
1779         ret = trf7970a_write(trf, TRF7970A_NFC_LOW_FIELD_LEVEL,
1780                         TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(0x3));
1781         if (ret)
1782                 goto out_err;
1783
1784         ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL,
1785                         TRF7970A_NFC_TARGET_LEVEL_RFDET(0x7));
1786         if (ret)
1787                 goto out_err;
1788
1789         trf->ddev = ddev;
1790         trf->cb = cb;
1791         trf->cb_arg = arg;
1792         trf->timeout = timeout;
1793         trf->ignore_timeout = false;
1794
1795         ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1796         if (ret)
1797                 goto out_err;
1798
1799         trf->state = mode_detect ? TRF7970A_ST_LISTENING_MD :
1800                                    TRF7970A_ST_LISTENING;
1801
1802         schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
1803
1804 out_err:
1805         mutex_unlock(&trf->lock);
1806         return ret;
1807 }
1808
1809 static int trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1810                 nfc_digital_cmd_complete_t cb, void *arg)
1811 {
1812         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1813
1814         dev_dbg(trf->dev, "Listen - state: %d, timeout: %d ms\n",
1815                         trf->state, timeout);
1816
1817         return _trf7970a_tg_listen(ddev, timeout, cb, arg, false);
1818 }
1819
1820 static int trf7970a_tg_listen_md(struct nfc_digital_dev *ddev,
1821                 u16 timeout, nfc_digital_cmd_complete_t cb, void *arg)
1822 {
1823         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1824         int ret;
1825
1826         dev_dbg(trf->dev, "Listen MD - state: %d, timeout: %d ms\n",
1827                         trf->state, timeout);
1828
1829         ret = trf7970a_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
1830                         NFC_DIGITAL_RF_TECH_106A);
1831         if (ret)
1832                 return ret;
1833
1834         ret = trf7970a_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1835                         NFC_DIGITAL_FRAMING_NFCA_NFC_DEP);
1836         if (ret)
1837                 return ret;
1838
1839         return _trf7970a_tg_listen(ddev, timeout, cb, arg, true);
1840 }
1841
1842 static int trf7970a_tg_get_rf_tech(struct nfc_digital_dev *ddev, u8 *rf_tech)
1843 {
1844         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1845
1846         dev_dbg(trf->dev, "Get RF Tech - state: %d, rf_tech: %d\n",
1847                         trf->state, trf->md_rf_tech);
1848
1849         *rf_tech = trf->md_rf_tech;
1850
1851         return 0;
1852 }
1853
1854 static void trf7970a_abort_cmd(struct nfc_digital_dev *ddev)
1855 {
1856         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1857
1858         dev_dbg(trf->dev, "Abort process initiated\n");
1859
1860         mutex_lock(&trf->lock);
1861
1862         switch (trf->state) {
1863         case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1864         case TRF7970A_ST_WAIT_FOR_RX_DATA:
1865         case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1866         case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1867                 trf->aborting = true;
1868                 break;
1869         case TRF7970A_ST_LISTENING:
1870                 trf->ignore_timeout = !cancel_delayed_work(&trf->timeout_work);
1871                 trf7970a_send_err_upstream(trf, -ECANCELED);
1872                 dev_dbg(trf->dev, "Abort process complete\n");
1873                 break;
1874         default:
1875                 break;
1876         }
1877
1878         mutex_unlock(&trf->lock);
1879 }
1880
1881 static struct nfc_digital_ops trf7970a_nfc_ops = {
1882         .in_configure_hw        = trf7970a_in_configure_hw,
1883         .in_send_cmd            = trf7970a_send_cmd,
1884         .tg_configure_hw        = trf7970a_tg_configure_hw,
1885         .tg_send_cmd            = trf7970a_send_cmd,
1886         .tg_listen              = trf7970a_tg_listen,
1887         .tg_listen_md           = trf7970a_tg_listen_md,
1888         .tg_get_rf_tech         = trf7970a_tg_get_rf_tech,
1889         .switch_rf              = trf7970a_switch_rf,
1890         .abort_cmd              = trf7970a_abort_cmd,
1891 };
1892
1893 static int trf7970a_power_up(struct trf7970a *trf)
1894 {
1895         int ret;
1896
1897         dev_dbg(trf->dev, "Powering up - state: %d\n", trf->state);
1898
1899         if (trf->state != TRF7970A_ST_PWR_OFF)
1900                 return 0;
1901
1902         ret = regulator_enable(trf->regulator);
1903         if (ret) {
1904                 dev_err(trf->dev, "%s - Can't enable VIN: %d\n", __func__, ret);
1905                 return ret;
1906         }
1907
1908         usleep_range(5000, 6000);
1909
1910         if (trf->en2_gpiod &&
1911             !(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW)) {
1912                 gpiod_set_value_cansleep(trf->en2_gpiod, 1);
1913                 usleep_range(1000, 2000);
1914         }
1915
1916         gpiod_set_value_cansleep(trf->en_gpiod, 1);
1917
1918         usleep_range(20000, 21000);
1919
1920         trf->state = TRF7970A_ST_RF_OFF;
1921
1922         return 0;
1923 }
1924
1925 static int trf7970a_power_down(struct trf7970a *trf)
1926 {
1927         int ret;
1928
1929         dev_dbg(trf->dev, "Powering down - state: %d\n", trf->state);
1930
1931         if (trf->state == TRF7970A_ST_PWR_OFF)
1932                 return 0;
1933
1934         if (trf->state != TRF7970A_ST_RF_OFF) {
1935                 dev_dbg(trf->dev, "Can't power down - not RF_OFF state (%d)\n",
1936                                 trf->state);
1937                 return -EBUSY;
1938         }
1939
1940         gpiod_set_value_cansleep(trf->en_gpiod, 0);
1941
1942         if (trf->en2_gpiod &&
1943             !(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW))
1944                 gpiod_set_value_cansleep(trf->en2_gpiod, 0);
1945
1946         ret = regulator_disable(trf->regulator);
1947         if (ret)
1948                 dev_err(trf->dev, "%s - Can't disable VIN: %d\n", __func__,
1949                                 ret);
1950
1951         trf->state = TRF7970A_ST_PWR_OFF;
1952
1953         return ret;
1954 }
1955
1956 static int trf7970a_startup(struct trf7970a *trf)
1957 {
1958         int ret;
1959
1960         ret = trf7970a_power_up(trf);
1961         if (ret)
1962                 return ret;
1963
1964         pm_runtime_set_active(trf->dev);
1965         pm_runtime_enable(trf->dev);
1966         pm_runtime_mark_last_busy(trf->dev);
1967
1968         return 0;
1969 }
1970
1971 static void trf7970a_shutdown(struct trf7970a *trf)
1972 {
1973         switch (trf->state) {
1974         case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1975         case TRF7970A_ST_WAIT_FOR_RX_DATA:
1976         case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1977         case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1978         case TRF7970A_ST_LISTENING:
1979                 trf7970a_send_err_upstream(trf, -ECANCELED);
1980                 /* FALLTHROUGH */
1981         case TRF7970A_ST_IDLE:
1982         case TRF7970A_ST_IDLE_RX_BLOCKED:
1983                 trf7970a_switch_rf_off(trf);
1984                 break;
1985         default:
1986                 break;
1987         }
1988
1989         pm_runtime_disable(trf->dev);
1990         pm_runtime_set_suspended(trf->dev);
1991
1992         trf7970a_power_down(trf);
1993 }
1994
1995 static int trf7970a_get_autosuspend_delay(struct device_node *np)
1996 {
1997         int autosuspend_delay, ret;
1998
1999         ret = of_property_read_u32(np, "autosuspend-delay", &autosuspend_delay);
2000         if (ret)
2001                 autosuspend_delay = TRF7970A_AUTOSUSPEND_DELAY;
2002
2003         return autosuspend_delay;
2004 }
2005
2006 static int trf7970a_probe(struct spi_device *spi)
2007 {
2008         struct device_node *np = spi->dev.of_node;
2009         struct trf7970a *trf;
2010         int uvolts, autosuspend_delay, ret;
2011         u32 clk_freq = TRF7970A_13MHZ_CLOCK_FREQUENCY;
2012
2013         if (!np) {
2014                 dev_err(&spi->dev, "No Device Tree entry\n");
2015                 return -EINVAL;
2016         }
2017
2018         trf = devm_kzalloc(&spi->dev, sizeof(*trf), GFP_KERNEL);
2019         if (!trf)
2020                 return -ENOMEM;
2021
2022         trf->state = TRF7970A_ST_PWR_OFF;
2023         trf->dev = &spi->dev;
2024         trf->spi = spi;
2025
2026         spi->mode = SPI_MODE_1;
2027         spi->bits_per_word = 8;
2028
2029         ret = spi_setup(spi);
2030         if (ret < 0) {
2031                 dev_err(trf->dev, "Can't set up SPI Communication\n");
2032                 return ret;
2033         }
2034
2035         if (of_property_read_bool(np, "t5t-rmb-extra-byte-quirk"))
2036                 trf->quirks |= TRF7970A_QUIRK_T5T_RMB_EXTRA_BYTE;
2037
2038         if (of_property_read_bool(np, "irq-status-read-quirk"))
2039                 trf->quirks |= TRF7970A_QUIRK_IRQ_STATUS_READ;
2040
2041         /* There are two enable pins - only EN must be present in the DT */
2042         trf->en_gpiod = devm_gpiod_get_index(trf->dev, "ti,enable", 0,
2043                                              GPIOD_OUT_LOW);
2044         if (IS_ERR(trf->en_gpiod)) {
2045                 dev_err(trf->dev, "No EN GPIO property\n");
2046                 return PTR_ERR(trf->en_gpiod);
2047         }
2048
2049         trf->en2_gpiod = devm_gpiod_get_index_optional(trf->dev, "ti,enable", 1,
2050                                                        GPIOD_OUT_LOW);
2051         if (!trf->en2_gpiod) {
2052                 dev_info(trf->dev, "No EN2 GPIO property\n");
2053         } else if (IS_ERR(trf->en2_gpiod)) {
2054                 dev_err(trf->dev, "Error getting EN2 GPIO property: %ld\n",
2055                         PTR_ERR(trf->en2_gpiod));
2056                 return PTR_ERR(trf->en2_gpiod);
2057         } else if (of_property_read_bool(np, "en2-rf-quirk")) {
2058                 trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW;
2059         }
2060
2061         of_property_read_u32(np, "clock-frequency", &clk_freq);
2062         if ((clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) ||
2063                 (clk_freq != TRF7970A_13MHZ_CLOCK_FREQUENCY)) {
2064                 dev_err(trf->dev,
2065                         "clock-frequency (%u Hz) unsupported\n",
2066                         clk_freq);
2067                 return -EINVAL;
2068         }
2069
2070         ret = devm_request_threaded_irq(trf->dev, spi->irq, NULL,
2071                         trf7970a_irq, IRQF_TRIGGER_RISING | IRQF_ONESHOT,
2072                         "trf7970a", trf);
2073         if (ret) {
2074                 dev_err(trf->dev, "Can't request IRQ#%d: %d\n", spi->irq, ret);
2075                 return ret;
2076         }
2077
2078         mutex_init(&trf->lock);
2079         INIT_DELAYED_WORK(&trf->timeout_work, trf7970a_timeout_work_handler);
2080
2081         trf->regulator = devm_regulator_get(&spi->dev, "vin");
2082         if (IS_ERR(trf->regulator)) {
2083                 ret = PTR_ERR(trf->regulator);
2084                 dev_err(trf->dev, "Can't get VIN regulator: %d\n", ret);
2085                 goto err_destroy_lock;
2086         }
2087
2088         ret = regulator_enable(trf->regulator);
2089         if (ret) {
2090                 dev_err(trf->dev, "Can't enable VIN: %d\n", ret);
2091                 goto err_destroy_lock;
2092         }
2093
2094         uvolts = regulator_get_voltage(trf->regulator);
2095         if (uvolts > 4000000)
2096                 trf->chip_status_ctrl = TRF7970A_CHIP_STATUS_VRS5_3;
2097
2098         trf->regulator = devm_regulator_get(&spi->dev, "vdd-io");
2099         if (IS_ERR(trf->regulator)) {
2100                 ret = PTR_ERR(trf->regulator);
2101                 dev_err(trf->dev, "Can't get VDD_IO regulator: %d\n", ret);
2102                 goto err_destroy_lock;
2103         }
2104
2105         ret = regulator_enable(trf->regulator);
2106         if (ret) {
2107                 dev_err(trf->dev, "Can't enable VDD_IO: %d\n", ret);
2108                 goto err_destroy_lock;
2109         }
2110
2111         if (regulator_get_voltage(trf->regulator) == 1800000) {
2112                 trf->io_ctrl = TRF7970A_REG_IO_CTRL_IO_LOW;
2113                 dev_dbg(trf->dev, "trf7970a config vdd_io to 1.8V\n");
2114         }
2115
2116         trf->ddev = nfc_digital_allocate_device(&trf7970a_nfc_ops,
2117                         TRF7970A_SUPPORTED_PROTOCOLS,
2118                         NFC_DIGITAL_DRV_CAPS_IN_CRC |
2119                                 NFC_DIGITAL_DRV_CAPS_TG_CRC, 0, 0);
2120         if (!trf->ddev) {
2121                 dev_err(trf->dev, "Can't allocate NFC digital device\n");
2122                 ret = -ENOMEM;
2123                 goto err_disable_regulator;
2124         }
2125
2126         nfc_digital_set_parent_dev(trf->ddev, trf->dev);
2127         nfc_digital_set_drvdata(trf->ddev, trf);
2128         spi_set_drvdata(spi, trf);
2129
2130         autosuspend_delay = trf7970a_get_autosuspend_delay(np);
2131
2132         pm_runtime_set_autosuspend_delay(trf->dev, autosuspend_delay);
2133         pm_runtime_use_autosuspend(trf->dev);
2134
2135         ret = trf7970a_startup(trf);
2136         if (ret)
2137                 goto err_free_ddev;
2138
2139         ret = nfc_digital_register_device(trf->ddev);
2140         if (ret) {
2141                 dev_err(trf->dev, "Can't register NFC digital device: %d\n",
2142                                 ret);
2143                 goto err_shutdown;
2144         }
2145
2146         return 0;
2147
2148 err_shutdown:
2149         trf7970a_shutdown(trf);
2150 err_free_ddev:
2151         nfc_digital_free_device(trf->ddev);
2152 err_disable_regulator:
2153         regulator_disable(trf->regulator);
2154 err_destroy_lock:
2155         mutex_destroy(&trf->lock);
2156         return ret;
2157 }
2158
2159 static int trf7970a_remove(struct spi_device *spi)
2160 {
2161         struct trf7970a *trf = spi_get_drvdata(spi);
2162
2163         mutex_lock(&trf->lock);
2164
2165         trf7970a_shutdown(trf);
2166
2167         mutex_unlock(&trf->lock);
2168
2169         nfc_digital_unregister_device(trf->ddev);
2170         nfc_digital_free_device(trf->ddev);
2171
2172         regulator_disable(trf->regulator);
2173
2174         mutex_destroy(&trf->lock);
2175
2176         return 0;
2177 }
2178
2179 #ifdef CONFIG_PM_SLEEP
2180 static int trf7970a_suspend(struct device *dev)
2181 {
2182         struct spi_device *spi = to_spi_device(dev);
2183         struct trf7970a *trf = spi_get_drvdata(spi);
2184
2185         dev_dbg(dev, "Suspend\n");
2186
2187         mutex_lock(&trf->lock);
2188
2189         trf7970a_shutdown(trf);
2190
2191         mutex_unlock(&trf->lock);
2192
2193         return 0;
2194 }
2195
2196 static int trf7970a_resume(struct device *dev)
2197 {
2198         struct spi_device *spi = to_spi_device(dev);
2199         struct trf7970a *trf = spi_get_drvdata(spi);
2200         int ret;
2201
2202         dev_dbg(dev, "Resume\n");
2203
2204         mutex_lock(&trf->lock);
2205
2206         ret = trf7970a_startup(trf);
2207
2208         mutex_unlock(&trf->lock);
2209
2210         return ret;
2211 }
2212 #endif
2213
2214 #ifdef CONFIG_PM
2215 static int trf7970a_pm_runtime_suspend(struct device *dev)
2216 {
2217         struct spi_device *spi = to_spi_device(dev);
2218         struct trf7970a *trf = spi_get_drvdata(spi);
2219         int ret;
2220
2221         dev_dbg(dev, "Runtime suspend\n");
2222
2223         mutex_lock(&trf->lock);
2224
2225         ret = trf7970a_power_down(trf);
2226
2227         mutex_unlock(&trf->lock);
2228
2229         return ret;
2230 }
2231
2232 static int trf7970a_pm_runtime_resume(struct device *dev)
2233 {
2234         struct spi_device *spi = to_spi_device(dev);
2235         struct trf7970a *trf = spi_get_drvdata(spi);
2236         int ret;
2237
2238         dev_dbg(dev, "Runtime resume\n");
2239
2240         ret = trf7970a_power_up(trf);
2241         if (!ret)
2242                 pm_runtime_mark_last_busy(dev);
2243
2244         return ret;
2245 }
2246 #endif
2247
2248 static const struct dev_pm_ops trf7970a_pm_ops = {
2249         SET_SYSTEM_SLEEP_PM_OPS(trf7970a_suspend, trf7970a_resume)
2250         SET_RUNTIME_PM_OPS(trf7970a_pm_runtime_suspend,
2251                         trf7970a_pm_runtime_resume, NULL)
2252 };
2253
2254 static const struct of_device_id trf7970a_of_match[] = {
2255         { .compatible = "ti,trf7970a", },
2256         {},
2257 };
2258 MODULE_DEVICE_TABLE(of, trf7970a_of_match);
2259
2260 static const struct spi_device_id trf7970a_id_table[] = {
2261         { "trf7970a", 0 },
2262         { }
2263 };
2264 MODULE_DEVICE_TABLE(spi, trf7970a_id_table);
2265
2266 static struct spi_driver trf7970a_spi_driver = {
2267         .probe          = trf7970a_probe,
2268         .remove         = trf7970a_remove,
2269         .id_table       = trf7970a_id_table,
2270         .driver         = {
2271                 .name   = "trf7970a",
2272                 .of_match_table = of_match_ptr(trf7970a_of_match),
2273                 .pm     = &trf7970a_pm_ops,
2274         },
2275 };
2276
2277 module_spi_driver(trf7970a_spi_driver);
2278
2279 MODULE_AUTHOR("Mark A. Greer <mgreer@animalcreek.com>");
2280 MODULE_LICENSE("GPL v2");
2281 MODULE_DESCRIPTION("TI trf7970a RFID/NFC Transceiver Driver");