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NFC: trf7970a: Remove unnecessary local variable initialization
[karo-tx-linux.git] / 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.h>
24 #include <linux/of.h>
25 #include <linux/of_gpio.h>
26 #include <linux/spi/spi.h>
27 #include <linux/regulator/consumer.h>
28
29 #include <net/nfc/nfc.h>
30 #include <net/nfc/digital.h>
31
32 /* There are 3 ways the host can communicate with the trf7970a:
33  * parallel mode, SPI with Slave Select (SS) mode, and SPI without
34  * SS mode.  The driver only supports the two SPI modes.
35  *
36  * The trf7970a is very timing sensitive and the VIN, EN2, and EN
37  * pins must asserted in that order and with specific delays in between.
38  * The delays used in the driver were provided by TI and have been
39  * confirmed to work with this driver.  There is a bug with the current
40  * version of the trf7970a that requires that EN2 remain low no matter
41  * what.  If it goes high, it will generate an RF field even when in
42  * passive target mode.  TI has indicated that the chip will work okay
43  * when EN2 is left low.  The 'en2-rf-quirk' device tree property
44  * indicates that trf7970a currently being used has the erratum and
45  * that EN2 must be kept low.
46  *
47  * Timeouts are implemented using the delayed workqueue kernel facility.
48  * Timeouts are required so things don't hang when there is no response
49  * from the trf7970a (or tag).  Using this mechanism creates a race with
50  * interrupts, however.  That is, an interrupt and a timeout could occur
51  * closely enough together that one is blocked by the mutex while the other
52  * executes.  When the timeout handler executes first and blocks the
53  * interrupt handler, it will eventually set the state to IDLE so the
54  * interrupt handler will check the state and exit with no harm done.
55  * When the interrupt handler executes first and blocks the timeout handler,
56  * the cancel_delayed_work() call will know that it didn't cancel the
57  * work item (i.e., timeout) and will return zero.  That return code is
58  * used by the timer handler to indicate that it should ignore the timeout
59  * once its unblocked.
60  *
61  * Aborting an active command isn't as simple as it seems because the only
62  * way to abort a command that's already been sent to the tag is so turn
63  * off power to the tag.  If we do that, though, we'd have to go through
64  * the entire anticollision procedure again but the digital layer doesn't
65  * support that.  So, if an abort is received before trf7970a_send_cmd()
66  * has sent the command to the tag, it simply returns -ECANCELED.  If the
67  * command has already been sent to the tag, then the driver continues
68  * normally and recieves the response data (or error) but just before
69  * sending the data upstream, it frees the rx_skb and sends -ECANCELED
70  * upstream instead.  If the command failed, that error will be sent
71  * upstream.
72  *
73  * When recieving data from a tag and the interrupt status register has
74  * only the SRX bit set, it means that all of the data has been received
75  * (once what's in the fifo has been read).  However, depending on timing
76  * an interrupt status with only the SRX bit set may not be recived.  In
77  * those cases, the timeout mechanism is used to wait 20 ms in case more
78  * data arrives.  After 20 ms, it is assumed that all of the data has been
79  * received and the accumulated rx data is sent upstream.  The
80  * 'TRF7970A_ST_WAIT_FOR_RX_DATA_CONT' state is used for this purpose
81  * (i.e., it indicates that some data has been received but we're not sure
82  * if there is more coming so a timeout in this state means all data has
83  * been received and there isn't an error).  The delay is 20 ms since delays
84  * of ~16 ms have been observed during testing.
85  *
86  * When transmitting a frame larger than the FIFO size (127 bytes), the
87  * driver will wait 20 ms for the FIFO to drain past the low-watermark
88  * and generate an interrupt.  The low-watermark set to 32 bytes so the
89  * interrupt should fire after 127 - 32 = 95 bytes have been sent.  At
90  * the lowest possible bit rate (6.62 kbps for 15693), it will take up
91  * to ~14.35 ms so 20 ms is used for the timeout.
92  *
93  * Type 2 write and sector select commands respond with a 4-bit ACK or NACK.
94  * Having only 4 bits in the FIFO won't normally generate an interrupt so
95  * driver enables the '4_bit_RX' bit of the Special Functions register 1
96  * to cause an interrupt in that case.  Leaving that bit for a read command
97  * messes up the data returned so it is only enabled when the framing is
98  * 'NFC_DIGITAL_FRAMING_NFCA_T2T' and the command is not a read command.
99  * Unfortunately, that means that the driver has to peek into tx frames
100  * when the framing is 'NFC_DIGITAL_FRAMING_NFCA_T2T'.  This is done by
101  * the trf7970a_per_cmd_config() routine.
102  *
103  * ISO/IEC 15693 frames specify whether to use single or double sub-carrier
104  * frequencies and whether to use low or high data rates in the flags byte
105  * of the frame.  This means that the driver has to peek at all 15693 frames
106  * to determine what speed to set the communication to.  In addition, write
107  * and lock commands use the OPTION flag to indicate that an EOF must be
108  * sent to the tag before it will send its response.  So the driver has to
109  * examine all frames for that reason too.
110  *
111  * It is unclear how long to wait before sending the EOF.  According to the
112  * Note under Table 1-1 in section 1.6 of
113  * http://www.ti.com/lit/ug/scbu011/scbu011.pdf, that wait should be at least
114  * 10 ms for TI Tag-it HF-I tags; however testing has shown that is not long
115  * enough so 20 ms is used.  So the timer is set to 40 ms - 20 ms to drain
116  * up to 127 bytes in the FIFO at the lowest bit rate plus another 20 ms to
117  * ensure the wait is long enough before sending the EOF.  This seems to work
118  * reliably.
119  */
120
121 #define TRF7970A_SUPPORTED_PROTOCOLS \
122                 (NFC_PROTO_MIFARE_MASK | NFC_PROTO_ISO14443_MASK |      \
123                  NFC_PROTO_ISO14443_B_MASK | NFC_PROTO_FELICA_MASK | \
124                  NFC_PROTO_ISO15693_MASK | NFC_PROTO_NFC_DEP_MASK)
125
126 #define TRF7970A_AUTOSUSPEND_DELAY              30000 /* 30 seconds */
127
128 #define TRF7970A_RX_SKB_ALLOC_SIZE              256
129
130 #define TRF7970A_FIFO_SIZE                      127
131
132 /* TX length is 3 nibbles long ==> 4KB - 1 bytes max */
133 #define TRF7970A_TX_MAX                         (4096 - 1)
134
135 #define TRF7970A_WAIT_FOR_TX_IRQ                20
136 #define TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT       20
137 #define TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT    20
138 #define TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF     40
139
140 /* Guard times for various RF technologies (in us) */
141 #define TRF7970A_GUARD_TIME_NFCA                5000
142 #define TRF7970A_GUARD_TIME_NFCB                5000
143 #define TRF7970A_GUARD_TIME_NFCF                20000
144 #define TRF7970A_GUARD_TIME_15693               1000
145
146 /* Quirks */
147 /* Erratum: When reading IRQ Status register on trf7970a, we must issue a
148  * read continuous command for IRQ Status and Collision Position registers.
149  */
150 #define TRF7970A_QUIRK_IRQ_STATUS_READ          BIT(0)
151 #define TRF7970A_QUIRK_EN2_MUST_STAY_LOW        BIT(1)
152
153 /* Direct commands */
154 #define TRF7970A_CMD_IDLE                       0x00
155 #define TRF7970A_CMD_SOFT_INIT                  0x03
156 #define TRF7970A_CMD_RF_COLLISION               0x04
157 #define TRF7970A_CMD_RF_COLLISION_RESPONSE_N    0x05
158 #define TRF7970A_CMD_RF_COLLISION_RESPONSE_0    0x06
159 #define TRF7970A_CMD_FIFO_RESET                 0x0f
160 #define TRF7970A_CMD_TRANSMIT_NO_CRC            0x10
161 #define TRF7970A_CMD_TRANSMIT                   0x11
162 #define TRF7970A_CMD_DELAY_TRANSMIT_NO_CRC      0x12
163 #define TRF7970A_CMD_DELAY_TRANSMIT             0x13
164 #define TRF7970A_CMD_EOF                        0x14
165 #define TRF7970A_CMD_CLOSE_SLOT                 0x15
166 #define TRF7970A_CMD_BLOCK_RX                   0x16
167 #define TRF7970A_CMD_ENABLE_RX                  0x17
168 #define TRF7970A_CMD_TEST_INT_RF                0x18
169 #define TRF7970A_CMD_TEST_EXT_RF                0x19
170 #define TRF7970A_CMD_RX_GAIN_ADJUST             0x1a
171
172 /* Bits determining whether its a direct command or register R/W,
173  * whether to use a continuous SPI transaction or not, and the actual
174  * direct cmd opcode or regster address.
175  */
176 #define TRF7970A_CMD_BIT_CTRL                   BIT(7)
177 #define TRF7970A_CMD_BIT_RW                     BIT(6)
178 #define TRF7970A_CMD_BIT_CONTINUOUS             BIT(5)
179 #define TRF7970A_CMD_BIT_OPCODE(opcode)         ((opcode) & 0x1f)
180
181 /* Registers addresses */
182 #define TRF7970A_CHIP_STATUS_CTRL               0x00
183 #define TRF7970A_ISO_CTRL                       0x01
184 #define TRF7970A_ISO14443B_TX_OPTIONS           0x02
185 #define TRF7970A_ISO14443A_HIGH_BITRATE_OPTIONS 0x03
186 #define TRF7970A_TX_TIMER_SETTING_H_BYTE        0x04
187 #define TRF7970A_TX_TIMER_SETTING_L_BYTE        0x05
188 #define TRF7970A_TX_PULSE_LENGTH_CTRL           0x06
189 #define TRF7970A_RX_NO_RESPONSE_WAIT            0x07
190 #define TRF7970A_RX_WAIT_TIME                   0x08
191 #define TRF7970A_MODULATOR_SYS_CLK_CTRL         0x09
192 #define TRF7970A_RX_SPECIAL_SETTINGS            0x0a
193 #define TRF7970A_REG_IO_CTRL                    0x0b
194 #define TRF7970A_IRQ_STATUS                     0x0c
195 #define TRF7970A_COLLISION_IRQ_MASK             0x0d
196 #define TRF7970A_COLLISION_POSITION             0x0e
197 #define TRF7970A_RSSI_OSC_STATUS                0x0f
198 #define TRF7970A_SPECIAL_FCN_REG1               0x10
199 #define TRF7970A_SPECIAL_FCN_REG2               0x11
200 #define TRF7970A_RAM1                           0x12
201 #define TRF7970A_RAM2                           0x13
202 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS      0x14
203 #define TRF7970A_NFC_LOW_FIELD_LEVEL            0x16
204 #define TRF7970A_NFCID1                         0x17
205 #define TRF7970A_NFC_TARGET_LEVEL               0x18
206 #define TRF79070A_NFC_TARGET_PROTOCOL           0x19
207 #define TRF7970A_TEST_REGISTER1                 0x1a
208 #define TRF7970A_TEST_REGISTER2                 0x1b
209 #define TRF7970A_FIFO_STATUS                    0x1c
210 #define TRF7970A_TX_LENGTH_BYTE1                0x1d
211 #define TRF7970A_TX_LENGTH_BYTE2                0x1e
212 #define TRF7970A_FIFO_IO_REGISTER               0x1f
213
214 /* Chip Status Control Register Bits */
215 #define TRF7970A_CHIP_STATUS_VRS5_3             BIT(0)
216 #define TRF7970A_CHIP_STATUS_REC_ON             BIT(1)
217 #define TRF7970A_CHIP_STATUS_AGC_ON             BIT(2)
218 #define TRF7970A_CHIP_STATUS_PM_ON              BIT(3)
219 #define TRF7970A_CHIP_STATUS_RF_PWR             BIT(4)
220 #define TRF7970A_CHIP_STATUS_RF_ON              BIT(5)
221 #define TRF7970A_CHIP_STATUS_DIRECT             BIT(6)
222 #define TRF7970A_CHIP_STATUS_STBY               BIT(7)
223
224 /* ISO Control Register Bits */
225 #define TRF7970A_ISO_CTRL_15693_SGL_1OF4_662    0x00
226 #define TRF7970A_ISO_CTRL_15693_SGL_1OF256_662  0x01
227 #define TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648   0x02
228 #define TRF7970A_ISO_CTRL_15693_SGL_1OF256_2648 0x03
229 #define TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a   0x04
230 #define TRF7970A_ISO_CTRL_15693_DBL_1OF256_667  0x05
231 #define TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669   0x06
232 #define TRF7970A_ISO_CTRL_15693_DBL_1OF256_2669 0x07
233 #define TRF7970A_ISO_CTRL_14443A_106            0x08
234 #define TRF7970A_ISO_CTRL_14443A_212            0x09
235 #define TRF7970A_ISO_CTRL_14443A_424            0x0a
236 #define TRF7970A_ISO_CTRL_14443A_848            0x0b
237 #define TRF7970A_ISO_CTRL_14443B_106            0x0c
238 #define TRF7970A_ISO_CTRL_14443B_212            0x0d
239 #define TRF7970A_ISO_CTRL_14443B_424            0x0e
240 #define TRF7970A_ISO_CTRL_14443B_848            0x0f
241 #define TRF7970A_ISO_CTRL_FELICA_212            0x1a
242 #define TRF7970A_ISO_CTRL_FELICA_424            0x1b
243 #define TRF7970A_ISO_CTRL_NFC_NFCA_106          0x01
244 #define TRF7970A_ISO_CTRL_NFC_NFCF_212          0x02
245 #define TRF7970A_ISO_CTRL_NFC_NFCF_424          0x03
246 #define TRF7970A_ISO_CTRL_NFC_CE_14443A         0x00
247 #define TRF7970A_ISO_CTRL_NFC_CE_14443B         0x01
248 #define TRF7970A_ISO_CTRL_NFC_CE                BIT(2)
249 #define TRF7970A_ISO_CTRL_NFC_ACTIVE            BIT(3)
250 #define TRF7970A_ISO_CTRL_NFC_INITIATOR         BIT(4)
251 #define TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE       BIT(5)
252 #define TRF7970A_ISO_CTRL_RFID                  BIT(5)
253 #define TRF7970A_ISO_CTRL_DIR_MODE              BIT(6)
254 #define TRF7970A_ISO_CTRL_RX_CRC_N              BIT(7)  /* true == No CRC */
255
256 #define TRF7970A_ISO_CTRL_RFID_SPEED_MASK       0x1f
257
258 /* Modulator and SYS_CLK Control Register Bits */
259 #define TRF7970A_MODULATOR_DEPTH(n)             ((n) & 0x7)
260 #define TRF7970A_MODULATOR_DEPTH_ASK10          (TRF7970A_MODULATOR_DEPTH(0))
261 #define TRF7970A_MODULATOR_DEPTH_OOK            (TRF7970A_MODULATOR_DEPTH(1))
262 #define TRF7970A_MODULATOR_DEPTH_ASK7           (TRF7970A_MODULATOR_DEPTH(2))
263 #define TRF7970A_MODULATOR_DEPTH_ASK8_5         (TRF7970A_MODULATOR_DEPTH(3))
264 #define TRF7970A_MODULATOR_DEPTH_ASK13          (TRF7970A_MODULATOR_DEPTH(4))
265 #define TRF7970A_MODULATOR_DEPTH_ASK16          (TRF7970A_MODULATOR_DEPTH(5))
266 #define TRF7970A_MODULATOR_DEPTH_ASK22          (TRF7970A_MODULATOR_DEPTH(6))
267 #define TRF7970A_MODULATOR_DEPTH_ASK30          (TRF7970A_MODULATOR_DEPTH(7))
268 #define TRF7970A_MODULATOR_EN_ANA               BIT(3)
269 #define TRF7970A_MODULATOR_CLK(n)               (((n) & 0x3) << 4)
270 #define TRF7970A_MODULATOR_CLK_DISABLED         (TRF7970A_MODULATOR_CLK(0))
271 #define TRF7970A_MODULATOR_CLK_3_6              (TRF7970A_MODULATOR_CLK(1))
272 #define TRF7970A_MODULATOR_CLK_6_13             (TRF7970A_MODULATOR_CLK(2))
273 #define TRF7970A_MODULATOR_CLK_13_27            (TRF7970A_MODULATOR_CLK(3))
274 #define TRF7970A_MODULATOR_EN_OOK               BIT(6)
275 #define TRF7970A_MODULATOR_27MHZ                BIT(7)
276
277 #define TRF7970A_RX_SPECIAL_SETTINGS_NO_LIM     BIT(0)
278 #define TRF7970A_RX_SPECIAL_SETTINGS_AGCR       BIT(1)
279 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_0DB     (0x0 << 2)
280 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_5DB     (0x1 << 2)
281 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_10DB    (0x2 << 2)
282 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_15DB    (0x3 << 2)
283 #define TRF7970A_RX_SPECIAL_SETTINGS_HBT        BIT(4)
284 #define TRF7970A_RX_SPECIAL_SETTINGS_M848       BIT(5)
285 #define TRF7970A_RX_SPECIAL_SETTINGS_C424       BIT(6)
286 #define TRF7970A_RX_SPECIAL_SETTINGS_C212       BIT(7)
287
288 #define TRF7970A_REG_IO_CTRL_VRS(v)             ((v) & 0x07)
289 #define TRF7970A_REG_IO_CTRL_IO_LOW             BIT(5)
290 #define TRF7970A_REG_IO_CTRL_EN_EXT_PA          BIT(6)
291 #define TRF7970A_REG_IO_CTRL_AUTO_REG           BIT(7)
292
293 /* IRQ Status Register Bits */
294 #define TRF7970A_IRQ_STATUS_NORESP              BIT(0) /* ISO15693 only */
295 #define TRF7970A_IRQ_STATUS_NFC_COL_ERROR       BIT(0)
296 #define TRF7970A_IRQ_STATUS_COL                 BIT(1)
297 #define TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR   BIT(2)
298 #define TRF7970A_IRQ_STATUS_NFC_RF              BIT(2)
299 #define TRF7970A_IRQ_STATUS_PARITY_ERROR        BIT(3)
300 #define TRF7970A_IRQ_STATUS_NFC_SDD             BIT(3)
301 #define TRF7970A_IRQ_STATUS_CRC_ERROR           BIT(4)
302 #define TRF7970A_IRQ_STATUS_NFC_PROTO_ERROR     BIT(4)
303 #define TRF7970A_IRQ_STATUS_FIFO                BIT(5)
304 #define TRF7970A_IRQ_STATUS_SRX                 BIT(6)
305 #define TRF7970A_IRQ_STATUS_TX                  BIT(7)
306
307 #define TRF7970A_IRQ_STATUS_ERROR                               \
308                 (TRF7970A_IRQ_STATUS_COL |                      \
309                  TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR |        \
310                  TRF7970A_IRQ_STATUS_PARITY_ERROR |             \
311                  TRF7970A_IRQ_STATUS_CRC_ERROR)
312
313 #define TRF7970A_RSSI_OSC_STATUS_RSSI_MASK      (BIT(2) | BIT(1) | BIT(0))
314 #define TRF7970A_RSSI_OSC_STATUS_RSSI_X_MASK    (BIT(5) | BIT(4) | BIT(3))
315 #define TRF7970A_RSSI_OSC_STATUS_RSSI_OSC_OK    BIT(6)
316
317 #define TRF7970A_SPECIAL_FCN_REG1_COL_7_6               BIT(0)
318 #define TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL           BIT(1)
319 #define TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX              BIT(2)
320 #define TRF7970A_SPECIAL_FCN_REG1_SP_DIR_MODE           BIT(3)
321 #define TRF7970A_SPECIAL_FCN_REG1_NEXT_SLOT_37US        BIT(4)
322 #define TRF7970A_SPECIAL_FCN_REG1_PAR43                 BIT(5)
323
324 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_124      (0x0 << 2)
325 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_120      (0x1 << 2)
326 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_112      (0x2 << 2)
327 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96       (0x3 << 2)
328 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_4        0x0
329 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_8        0x1
330 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_16       0x2
331 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32       0x3
332
333 #define TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(v)   ((v) & 0x07)
334 #define TRF7970A_NFC_LOW_FIELD_LEVEL_CLEX_DIS   BIT(7)
335
336 #define TRF7970A_NFC_TARGET_LEVEL_RFDET(v)      ((v) & 0x07)
337 #define TRF7970A_NFC_TARGET_LEVEL_HI_RF         BIT(3)
338 #define TRF7970A_NFC_TARGET_LEVEL_SDD_EN        BIT(3)
339 #define TRF7970A_NFC_TARGET_LEVEL_LD_S_4BYTES   (0x0 << 6)
340 #define TRF7970A_NFC_TARGET_LEVEL_LD_S_7BYTES   (0x1 << 6)
341 #define TRF7970A_NFC_TARGET_LEVEL_LD_S_10BYTES  (0x2 << 6)
342
343 #define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106         BIT(0)
344 #define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_212         BIT(1)
345 #define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_424         (BIT(0) | BIT(1))
346 #define TRF79070A_NFC_TARGET_PROTOCOL_PAS_14443B        BIT(2)
347 #define TRF79070A_NFC_TARGET_PROTOCOL_PAS_106           BIT(3)
348 #define TRF79070A_NFC_TARGET_PROTOCOL_FELICA            BIT(4)
349 #define TRF79070A_NFC_TARGET_PROTOCOL_RF_L              BIT(6)
350 #define TRF79070A_NFC_TARGET_PROTOCOL_RF_H              BIT(7)
351
352 #define TRF79070A_NFC_TARGET_PROTOCOL_106A              \
353          (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |          \
354           TRF79070A_NFC_TARGET_PROTOCOL_RF_L |          \
355           TRF79070A_NFC_TARGET_PROTOCOL_PAS_106 |       \
356           TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106)
357
358 #define TRF79070A_NFC_TARGET_PROTOCOL_106B              \
359          (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |          \
360           TRF79070A_NFC_TARGET_PROTOCOL_RF_L |          \
361           TRF79070A_NFC_TARGET_PROTOCOL_PAS_14443B |    \
362           TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106)
363
364 #define TRF79070A_NFC_TARGET_PROTOCOL_212F              \
365          (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |          \
366           TRF79070A_NFC_TARGET_PROTOCOL_RF_L |          \
367           TRF79070A_NFC_TARGET_PROTOCOL_FELICA |        \
368           TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_212)
369
370 #define TRF79070A_NFC_TARGET_PROTOCOL_424F              \
371          (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |          \
372           TRF79070A_NFC_TARGET_PROTOCOL_RF_L |          \
373           TRF79070A_NFC_TARGET_PROTOCOL_FELICA |        \
374           TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_424)
375
376 #define TRF7970A_FIFO_STATUS_OVERFLOW           BIT(7)
377
378 /* NFC (ISO/IEC 14443A) Type 2 Tag commands */
379 #define NFC_T2T_CMD_READ                        0x30
380
381 /* ISO 15693 commands codes */
382 #define ISO15693_CMD_INVENTORY                  0x01
383 #define ISO15693_CMD_READ_SINGLE_BLOCK          0x20
384 #define ISO15693_CMD_WRITE_SINGLE_BLOCK         0x21
385 #define ISO15693_CMD_LOCK_BLOCK                 0x22
386 #define ISO15693_CMD_READ_MULTIPLE_BLOCK        0x23
387 #define ISO15693_CMD_WRITE_MULTIPLE_BLOCK       0x24
388 #define ISO15693_CMD_SELECT                     0x25
389 #define ISO15693_CMD_RESET_TO_READY             0x26
390 #define ISO15693_CMD_WRITE_AFI                  0x27
391 #define ISO15693_CMD_LOCK_AFI                   0x28
392 #define ISO15693_CMD_WRITE_DSFID                0x29
393 #define ISO15693_CMD_LOCK_DSFID                 0x2a
394 #define ISO15693_CMD_GET_SYSTEM_INFO            0x2b
395 #define ISO15693_CMD_GET_MULTIPLE_BLOCK_SECURITY_STATUS 0x2c
396
397 /* ISO 15693 request and response flags */
398 #define ISO15693_REQ_FLAG_SUB_CARRIER           BIT(0)
399 #define ISO15693_REQ_FLAG_DATA_RATE             BIT(1)
400 #define ISO15693_REQ_FLAG_INVENTORY             BIT(2)
401 #define ISO15693_REQ_FLAG_PROTOCOL_EXT          BIT(3)
402 #define ISO15693_REQ_FLAG_SELECT                BIT(4)
403 #define ISO15693_REQ_FLAG_AFI                   BIT(4)
404 #define ISO15693_REQ_FLAG_ADDRESS               BIT(5)
405 #define ISO15693_REQ_FLAG_NB_SLOTS              BIT(5)
406 #define ISO15693_REQ_FLAG_OPTION                BIT(6)
407
408 #define ISO15693_REQ_FLAG_SPEED_MASK \
409                 (ISO15693_REQ_FLAG_SUB_CARRIER | ISO15693_REQ_FLAG_DATA_RATE)
410
411 enum trf7970a_state {
412         TRF7970A_ST_PWR_OFF,
413         TRF7970A_ST_RF_OFF,
414         TRF7970A_ST_IDLE,
415         TRF7970A_ST_IDLE_RX_BLOCKED,
416         TRF7970A_ST_WAIT_FOR_TX_FIFO,
417         TRF7970A_ST_WAIT_FOR_RX_DATA,
418         TRF7970A_ST_WAIT_FOR_RX_DATA_CONT,
419         TRF7970A_ST_WAIT_TO_ISSUE_EOF,
420         TRF7970A_ST_LISTENING,
421         TRF7970A_ST_LISTENING_MD,
422         TRF7970A_ST_MAX
423 };
424
425 struct trf7970a {
426         enum trf7970a_state             state;
427         struct device                   *dev;
428         struct spi_device               *spi;
429         struct regulator                *regulator;
430         struct nfc_digital_dev          *ddev;
431         u32                             quirks;
432         bool                            is_initiator;
433         bool                            aborting;
434         struct sk_buff                  *tx_skb;
435         struct sk_buff                  *rx_skb;
436         nfc_digital_cmd_complete_t      cb;
437         void                            *cb_arg;
438         u8                              chip_status_ctrl;
439         u8                              iso_ctrl;
440         u8                              iso_ctrl_tech;
441         u8                              modulator_sys_clk_ctrl;
442         u8                              special_fcn_reg1;
443         unsigned int                    guard_time;
444         int                             technology;
445         int                             framing;
446         u8                              md_rf_tech;
447         u8                              tx_cmd;
448         bool                            issue_eof;
449         int                             en2_gpio;
450         int                             en_gpio;
451         struct mutex                    lock;
452         unsigned int                    timeout;
453         bool                            ignore_timeout;
454         struct delayed_work             timeout_work;
455 };
456
457
458 static int trf7970a_cmd(struct trf7970a *trf, u8 opcode)
459 {
460         u8 cmd = TRF7970A_CMD_BIT_CTRL | TRF7970A_CMD_BIT_OPCODE(opcode);
461         int ret;
462
463         dev_dbg(trf->dev, "cmd: 0x%x\n", cmd);
464
465         ret = spi_write(trf->spi, &cmd, 1);
466         if (ret)
467                 dev_err(trf->dev, "%s - cmd: 0x%x, ret: %d\n", __func__, cmd,
468                                 ret);
469         return ret;
470 }
471
472 static int trf7970a_read(struct trf7970a *trf, u8 reg, u8 *val)
473 {
474         u8 addr = TRF7970A_CMD_BIT_RW | reg;
475         int ret;
476
477         ret = spi_write_then_read(trf->spi, &addr, 1, val, 1);
478         if (ret)
479                 dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
480                                 ret);
481
482         dev_dbg(trf->dev, "read(0x%x): 0x%x\n", addr, *val);
483
484         return ret;
485 }
486
487 static int trf7970a_read_cont(struct trf7970a *trf, u8 reg, u8 *buf, size_t len)
488 {
489         u8 addr = reg | TRF7970A_CMD_BIT_RW | TRF7970A_CMD_BIT_CONTINUOUS;
490         struct spi_transfer t[2];
491         struct spi_message m;
492         int ret;
493
494         dev_dbg(trf->dev, "read_cont(0x%x, %zd)\n", addr, len);
495
496         spi_message_init(&m);
497
498         memset(&t, 0, sizeof(t));
499
500         t[0].tx_buf = &addr;
501         t[0].len = sizeof(addr);
502         spi_message_add_tail(&t[0], &m);
503
504         t[1].rx_buf = buf;
505         t[1].len = len;
506         spi_message_add_tail(&t[1], &m);
507
508         ret = spi_sync(trf->spi, &m);
509         if (ret)
510                 dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
511                                 ret);
512         return ret;
513 }
514
515 static int trf7970a_write(struct trf7970a *trf, u8 reg, u8 val)
516 {
517         u8 buf[2] = { reg, val };
518         int ret;
519
520         dev_dbg(trf->dev, "write(0x%x): 0x%x\n", reg, val);
521
522         ret = spi_write(trf->spi, buf, 2);
523         if (ret)
524                 dev_err(trf->dev, "%s - write: 0x%x 0x%x, ret: %d\n", __func__,
525                                 buf[0], buf[1], ret);
526
527         return ret;
528 }
529
530 static int trf7970a_read_irqstatus(struct trf7970a *trf, u8 *status)
531 {
532         int ret;
533         u8 buf[2];
534         u8 addr;
535
536         addr = TRF7970A_IRQ_STATUS | TRF7970A_CMD_BIT_RW;
537
538         if (trf->quirks & TRF7970A_QUIRK_IRQ_STATUS_READ) {
539                 addr |= TRF7970A_CMD_BIT_CONTINUOUS;
540                 ret = spi_write_then_read(trf->spi, &addr, 1, buf, 2);
541         } else {
542                 ret = spi_write_then_read(trf->spi, &addr, 1, buf, 1);
543         }
544
545         if (ret)
546                 dev_err(trf->dev, "%s - irqstatus: Status read failed: %d\n",
547                                 __func__, ret);
548         else
549                 *status = buf[0];
550
551         return ret;
552 }
553
554 static int trf7970a_read_target_proto(struct trf7970a *trf, u8 *target_proto)
555 {
556         int ret;
557         u8 buf[2];
558         u8 addr;
559
560         addr = TRF79070A_NFC_TARGET_PROTOCOL | TRF7970A_CMD_BIT_RW |
561                 TRF7970A_CMD_BIT_CONTINUOUS;
562
563         ret = spi_write_then_read(trf->spi, &addr, 1, buf, 2);
564         if (ret)
565                 dev_err(trf->dev, "%s - target_proto: Read failed: %d\n",
566                                 __func__, ret);
567         else
568                 *target_proto = buf[0];
569
570         return ret;
571 }
572
573 static int trf7970a_mode_detect(struct trf7970a *trf, u8 *rf_tech)
574 {
575         int ret;
576         u8 target_proto, tech;
577
578         ret = trf7970a_read_target_proto(trf, &target_proto);
579         if (ret)
580                 return ret;
581
582         switch (target_proto) {
583         case TRF79070A_NFC_TARGET_PROTOCOL_106A:
584                 tech = NFC_DIGITAL_RF_TECH_106A;
585                 break;
586         case TRF79070A_NFC_TARGET_PROTOCOL_106B:
587                 tech = NFC_DIGITAL_RF_TECH_106B;
588                 break;
589         case TRF79070A_NFC_TARGET_PROTOCOL_212F:
590                 tech = NFC_DIGITAL_RF_TECH_212F;
591                 break;
592         case TRF79070A_NFC_TARGET_PROTOCOL_424F:
593                 tech = NFC_DIGITAL_RF_TECH_424F;
594                 break;
595         default:
596                 dev_dbg(trf->dev, "%s - mode_detect: target_proto: 0x%x\n",
597                                 __func__, target_proto);
598                 return -EIO;
599         }
600
601         *rf_tech = tech;
602
603         return ret;
604 }
605
606 static void trf7970a_send_upstream(struct trf7970a *trf)
607 {
608         dev_kfree_skb_any(trf->tx_skb);
609         trf->tx_skb = NULL;
610
611         if (trf->rx_skb && !IS_ERR(trf->rx_skb) && !trf->aborting)
612                 print_hex_dump_debug("trf7970a rx data: ", DUMP_PREFIX_NONE,
613                                 16, 1, trf->rx_skb->data, trf->rx_skb->len,
614                                 false);
615
616         trf->state = TRF7970A_ST_IDLE;
617
618         if (trf->aborting) {
619                 dev_dbg(trf->dev, "Abort process complete\n");
620
621                 if (!IS_ERR(trf->rx_skb)) {
622                         kfree_skb(trf->rx_skb);
623                         trf->rx_skb = ERR_PTR(-ECANCELED);
624                 }
625
626                 trf->aborting = false;
627         }
628
629         trf->cb(trf->ddev, trf->cb_arg, trf->rx_skb);
630
631         trf->rx_skb = NULL;
632 }
633
634 static void trf7970a_send_err_upstream(struct trf7970a *trf, int errno)
635 {
636         dev_dbg(trf->dev, "Error - state: %d, errno: %d\n", trf->state, errno);
637
638         cancel_delayed_work(&trf->timeout_work);
639
640         kfree_skb(trf->rx_skb);
641         trf->rx_skb = ERR_PTR(errno);
642
643         trf7970a_send_upstream(trf);
644 }
645
646 static int trf7970a_transmit(struct trf7970a *trf, struct sk_buff *skb,
647                 unsigned int len, u8 *prefix, unsigned int prefix_len)
648 {
649         struct spi_transfer t[2];
650         struct spi_message m;
651         unsigned int timeout;
652         int ret;
653
654         print_hex_dump_debug("trf7970a tx data: ", DUMP_PREFIX_NONE,
655                         16, 1, skb->data, len, false);
656
657         spi_message_init(&m);
658
659         memset(&t, 0, sizeof(t));
660
661         t[0].tx_buf = prefix;
662         t[0].len = prefix_len;
663         spi_message_add_tail(&t[0], &m);
664
665         t[1].tx_buf = skb->data;
666         t[1].len = len;
667         spi_message_add_tail(&t[1], &m);
668
669         ret = spi_sync(trf->spi, &m);
670         if (ret) {
671                 dev_err(trf->dev, "%s - Can't send tx data: %d\n", __func__,
672                                 ret);
673                 return ret;
674         }
675
676         skb_pull(skb, len);
677
678         if (skb->len > 0) {
679                 trf->state = TRF7970A_ST_WAIT_FOR_TX_FIFO;
680                 timeout = TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT;
681         } else {
682                 if (trf->issue_eof) {
683                         trf->state = TRF7970A_ST_WAIT_TO_ISSUE_EOF;
684                         timeout = TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF;
685                 } else {
686                         trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
687
688                         if (!trf->timeout)
689                                 timeout = TRF7970A_WAIT_FOR_TX_IRQ;
690                         else
691                                 timeout = trf->timeout;
692                 }
693         }
694
695         dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n", timeout,
696                         trf->state);
697
698         schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
699
700         return 0;
701 }
702
703 static void trf7970a_fill_fifo(struct trf7970a *trf)
704 {
705         struct sk_buff *skb = trf->tx_skb;
706         unsigned int len;
707         int ret;
708         u8 fifo_bytes;
709         u8 prefix;
710
711         ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
712         if (ret) {
713                 trf7970a_send_err_upstream(trf, ret);
714                 return;
715         }
716
717         dev_dbg(trf->dev, "Filling FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
718
719         fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
720
721         /* Calculate how much more data can be written to the fifo */
722         len = TRF7970A_FIFO_SIZE - fifo_bytes;
723         if (!len) {
724                 schedule_delayed_work(&trf->timeout_work,
725                         msecs_to_jiffies(TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT));
726                 return;
727         }
728
729         len = min(skb->len, len);
730
731         prefix = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_FIFO_IO_REGISTER;
732
733         ret = trf7970a_transmit(trf, skb, len, &prefix, sizeof(prefix));
734         if (ret)
735                 trf7970a_send_err_upstream(trf, ret);
736 }
737
738 static void trf7970a_drain_fifo(struct trf7970a *trf, u8 status)
739 {
740         struct sk_buff *skb = trf->rx_skb;
741         int ret;
742         u8 fifo_bytes;
743
744         if (status & TRF7970A_IRQ_STATUS_ERROR) {
745                 trf7970a_send_err_upstream(trf, -EIO);
746                 return;
747         }
748
749         ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
750         if (ret) {
751                 trf7970a_send_err_upstream(trf, ret);
752                 return;
753         }
754
755         dev_dbg(trf->dev, "Draining FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
756
757         fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
758
759         if (!fifo_bytes)
760                 goto no_rx_data;
761
762         if (fifo_bytes > skb_tailroom(skb)) {
763                 skb = skb_copy_expand(skb, skb_headroom(skb),
764                                 max_t(int, fifo_bytes,
765                                         TRF7970A_RX_SKB_ALLOC_SIZE),
766                                 GFP_KERNEL);
767                 if (!skb) {
768                         trf7970a_send_err_upstream(trf, -ENOMEM);
769                         return;
770                 }
771
772                 kfree_skb(trf->rx_skb);
773                 trf->rx_skb = skb;
774         }
775
776         ret = trf7970a_read_cont(trf, TRF7970A_FIFO_IO_REGISTER,
777                         skb_put(skb, fifo_bytes), fifo_bytes);
778         if (ret) {
779                 trf7970a_send_err_upstream(trf, ret);
780                 return;
781         }
782
783         /* If received Type 2 ACK/NACK, shift right 4 bits and pass up */
784         if ((trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T) && (skb->len == 1) &&
785                         (trf->special_fcn_reg1 ==
786                                  TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX)) {
787                 skb->data[0] >>= 4;
788                 status = TRF7970A_IRQ_STATUS_SRX;
789         } else {
790                 trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA_CONT;
791
792                 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
793                 if (ret) {
794                         trf7970a_send_err_upstream(trf, ret);
795                         return;
796                 }
797
798                 fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
799
800                 /* If there are bytes in the FIFO, set status to '0' so
801                  * the if stmt below doesn't fire and the driver will wait
802                  * for the trf7970a to generate another RX interrupt.
803                  */
804                 if (fifo_bytes)
805                         status = 0;
806         }
807
808 no_rx_data:
809         if (status == TRF7970A_IRQ_STATUS_SRX) { /* Receive complete */
810                 trf7970a_send_upstream(trf);
811                 return;
812         }
813
814         dev_dbg(trf->dev, "Setting timeout for %d ms\n",
815                         TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT);
816
817         schedule_delayed_work(&trf->timeout_work,
818                         msecs_to_jiffies(TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT));
819 }
820
821 static irqreturn_t trf7970a_irq(int irq, void *dev_id)
822 {
823         struct trf7970a *trf = dev_id;
824         int ret;
825         u8 status, fifo_bytes, iso_ctrl;
826
827         mutex_lock(&trf->lock);
828
829         if (trf->state == TRF7970A_ST_RF_OFF) {
830                 mutex_unlock(&trf->lock);
831                 return IRQ_NONE;
832         }
833
834         ret = trf7970a_read_irqstatus(trf, &status);
835         if (ret) {
836                 mutex_unlock(&trf->lock);
837                 return IRQ_NONE;
838         }
839
840         dev_dbg(trf->dev, "IRQ - state: %d, status: 0x%x\n", trf->state,
841                         status);
842
843         if (!status) {
844                 mutex_unlock(&trf->lock);
845                 return IRQ_NONE;
846         }
847
848         switch (trf->state) {
849         case TRF7970A_ST_IDLE:
850         case TRF7970A_ST_IDLE_RX_BLOCKED:
851                 /* If initiator and getting interrupts caused by RF noise,
852                  * turn off the receiver to avoid unnecessary interrupts.
853                  * It will be turned back on in trf7970a_send_cmd() when
854                  * the next command is issued.
855                  */
856                 if (trf->is_initiator && (status & TRF7970A_IRQ_STATUS_ERROR)) {
857                         trf7970a_cmd(trf, TRF7970A_CMD_BLOCK_RX);
858                         trf->state = TRF7970A_ST_IDLE_RX_BLOCKED;
859                 }
860
861                 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
862                 break;
863         case TRF7970A_ST_WAIT_FOR_TX_FIFO:
864                 if (status & TRF7970A_IRQ_STATUS_TX) {
865                         trf->ignore_timeout =
866                                 !cancel_delayed_work(&trf->timeout_work);
867                         trf7970a_fill_fifo(trf);
868                 } else {
869                         trf7970a_send_err_upstream(trf, -EIO);
870                 }
871                 break;
872         case TRF7970A_ST_WAIT_FOR_RX_DATA:
873         case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
874                 if (status & TRF7970A_IRQ_STATUS_SRX) {
875                         trf->ignore_timeout =
876                                 !cancel_delayed_work(&trf->timeout_work);
877                         trf7970a_drain_fifo(trf, status);
878                 } else if (status & TRF7970A_IRQ_STATUS_FIFO) {
879                         ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS,
880                                         &fifo_bytes);
881
882                         fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
883
884                         if (ret)
885                                 trf7970a_send_err_upstream(trf, ret);
886                         else if (!fifo_bytes)
887                                 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
888                 } else if ((status == TRF7970A_IRQ_STATUS_TX) ||
889                                 (!trf->is_initiator &&
890                                  (status == (TRF7970A_IRQ_STATUS_TX |
891                                              TRF7970A_IRQ_STATUS_NFC_RF)))) {
892                         trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
893
894                         if (!trf->timeout) {
895                                 trf->ignore_timeout = !cancel_delayed_work(
896                                                 &trf->timeout_work);
897                                 trf->rx_skb = ERR_PTR(0);
898                                 trf7970a_send_upstream(trf);
899                                 break;
900                         }
901
902                         if (trf->is_initiator)
903                                 break;
904
905                         iso_ctrl = trf->iso_ctrl;
906
907                         switch (trf->framing) {
908                         case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
909                                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
910                                 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
911                                 trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
912                                 break;
913                         case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
914                                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
915                                 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
916                                 trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
917                                 break;
918                         case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
919                                 ret = trf7970a_write(trf,
920                                         TRF7970A_SPECIAL_FCN_REG1,
921                                         TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL);
922                                 if (ret)
923                                         return ret;
924
925                                 trf->special_fcn_reg1 =
926                                         TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL;
927                                 break;
928                         default:
929                                 break;
930                         }
931
932                         if (iso_ctrl != trf->iso_ctrl) {
933                                 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
934                                                 iso_ctrl);
935                                 if (ret)
936                                         return ret;
937
938                                 trf->iso_ctrl = iso_ctrl;
939                         }
940                 } else {
941                         trf7970a_send_err_upstream(trf, -EIO);
942                 }
943                 break;
944         case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
945                 if (status != TRF7970A_IRQ_STATUS_TX)
946                         trf7970a_send_err_upstream(trf, -EIO);
947                 break;
948         case TRF7970A_ST_LISTENING:
949                 if (status & TRF7970A_IRQ_STATUS_SRX) {
950                         trf->ignore_timeout =
951                                 !cancel_delayed_work(&trf->timeout_work);
952                         trf7970a_drain_fifo(trf, status);
953                 } else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
954                         trf7970a_send_err_upstream(trf, -EIO);
955                 }
956                 break;
957         case TRF7970A_ST_LISTENING_MD:
958                 if (status & TRF7970A_IRQ_STATUS_SRX) {
959                         trf->ignore_timeout =
960                                 !cancel_delayed_work(&trf->timeout_work);
961
962                         ret = trf7970a_mode_detect(trf, &trf->md_rf_tech);
963                         if (ret) {
964                                 trf7970a_send_err_upstream(trf, ret);
965                         } else {
966                                 trf->state = TRF7970A_ST_LISTENING;
967                                 trf7970a_drain_fifo(trf, status);
968                         }
969                 } else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
970                         trf7970a_send_err_upstream(trf, -EIO);
971                 }
972                 break;
973         default:
974                 dev_err(trf->dev, "%s - Driver in invalid state: %d\n",
975                                 __func__, trf->state);
976         }
977
978         mutex_unlock(&trf->lock);
979         return IRQ_HANDLED;
980 }
981
982 static void trf7970a_issue_eof(struct trf7970a *trf)
983 {
984         int ret;
985
986         dev_dbg(trf->dev, "Issuing EOF\n");
987
988         ret = trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
989         if (ret)
990                 trf7970a_send_err_upstream(trf, ret);
991
992         ret = trf7970a_cmd(trf, TRF7970A_CMD_EOF);
993         if (ret)
994                 trf7970a_send_err_upstream(trf, ret);
995
996         trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
997
998         dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n",
999                         trf->timeout, trf->state);
1000
1001         schedule_delayed_work(&trf->timeout_work,
1002                         msecs_to_jiffies(trf->timeout));
1003 }
1004
1005 static void trf7970a_timeout_work_handler(struct work_struct *work)
1006 {
1007         struct trf7970a *trf = container_of(work, struct trf7970a,
1008                         timeout_work.work);
1009
1010         dev_dbg(trf->dev, "Timeout - state: %d, ignore_timeout: %d\n",
1011                         trf->state, trf->ignore_timeout);
1012
1013         mutex_lock(&trf->lock);
1014
1015         if (trf->ignore_timeout)
1016                 trf->ignore_timeout = false;
1017         else if (trf->state == TRF7970A_ST_WAIT_FOR_RX_DATA_CONT)
1018                 trf7970a_drain_fifo(trf, TRF7970A_IRQ_STATUS_SRX);
1019         else if (trf->state == TRF7970A_ST_WAIT_TO_ISSUE_EOF)
1020                 trf7970a_issue_eof(trf);
1021         else
1022                 trf7970a_send_err_upstream(trf, -ETIMEDOUT);
1023
1024         mutex_unlock(&trf->lock);
1025 }
1026
1027 static int trf7970a_init(struct trf7970a *trf)
1028 {
1029         int ret;
1030
1031         dev_dbg(trf->dev, "Initializing device - state: %d\n", trf->state);
1032
1033         ret = trf7970a_cmd(trf, TRF7970A_CMD_SOFT_INIT);
1034         if (ret)
1035                 goto err_out;
1036
1037         ret = trf7970a_cmd(trf, TRF7970A_CMD_IDLE);
1038         if (ret)
1039                 goto err_out;
1040
1041         usleep_range(1000, 2000);
1042
1043         trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1044
1045         ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL, 0);
1046         if (ret)
1047                 goto err_out;
1048
1049         trf->modulator_sys_clk_ctrl = 0;
1050
1051         ret = trf7970a_write(trf, TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS,
1052                         TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 |
1053                         TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32);
1054         if (ret)
1055                 goto err_out;
1056
1057         ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1, 0);
1058         if (ret)
1059                 goto err_out;
1060
1061         trf->special_fcn_reg1 = 0;
1062
1063         trf->iso_ctrl = 0xff;
1064         return 0;
1065
1066 err_out:
1067         dev_dbg(trf->dev, "Couldn't init device: %d\n", ret);
1068         return ret;
1069 }
1070
1071 static void trf7970a_switch_rf_off(struct trf7970a *trf)
1072 {
1073         if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1074                         (trf->state == TRF7970A_ST_RF_OFF))
1075                 return;
1076
1077         dev_dbg(trf->dev, "Switching rf off\n");
1078
1079         trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1080
1081         trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL, trf->chip_status_ctrl);
1082
1083         trf->aborting = false;
1084         trf->state = TRF7970A_ST_RF_OFF;
1085
1086         pm_runtime_mark_last_busy(trf->dev);
1087         pm_runtime_put_autosuspend(trf->dev);
1088 }
1089
1090 static int trf7970a_switch_rf_on(struct trf7970a *trf)
1091 {
1092         int ret;
1093
1094         dev_dbg(trf->dev, "Switching rf on\n");
1095
1096         pm_runtime_get_sync(trf->dev);
1097
1098         if (trf->state != TRF7970A_ST_RF_OFF) { /* Power on, RF off */
1099                 dev_err(trf->dev, "%s - Incorrect state: %d\n", __func__,
1100                                 trf->state);
1101                 return -EINVAL;
1102         }
1103
1104         ret = trf7970a_init(trf);
1105         if (ret) {
1106                 dev_err(trf->dev, "%s - Can't initialize: %d\n", __func__, ret);
1107                 return ret;
1108         }
1109
1110         trf->state = TRF7970A_ST_IDLE;
1111
1112         return 0;
1113 }
1114
1115 static int trf7970a_switch_rf(struct nfc_digital_dev *ddev, bool on)
1116 {
1117         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1118         int ret = 0;
1119
1120         dev_dbg(trf->dev, "Switching RF - state: %d, on: %d\n", trf->state, on);
1121
1122         mutex_lock(&trf->lock);
1123
1124         if (on) {
1125                 switch (trf->state) {
1126                 case TRF7970A_ST_PWR_OFF:
1127                 case TRF7970A_ST_RF_OFF:
1128                         ret = trf7970a_switch_rf_on(trf);
1129                         break;
1130                 case TRF7970A_ST_IDLE:
1131                 case TRF7970A_ST_IDLE_RX_BLOCKED:
1132                         break;
1133                 default:
1134                         dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1135                                         __func__, trf->state, on);
1136                         trf7970a_switch_rf_off(trf);
1137                         ret = -EINVAL;
1138                 }
1139         } else {
1140                 switch (trf->state) {
1141                 case TRF7970A_ST_PWR_OFF:
1142                 case TRF7970A_ST_RF_OFF:
1143                         break;
1144                 default:
1145                         dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1146                                         __func__, trf->state, on);
1147                         ret = -EINVAL;
1148                         /* FALLTHROUGH */
1149                 case TRF7970A_ST_IDLE:
1150                 case TRF7970A_ST_IDLE_RX_BLOCKED:
1151                 case TRF7970A_ST_WAIT_FOR_RX_DATA:
1152                 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1153                         trf7970a_switch_rf_off(trf);
1154                 }
1155         }
1156
1157         mutex_unlock(&trf->lock);
1158         return ret;
1159 }
1160
1161 static int trf7970a_in_config_rf_tech(struct trf7970a *trf, int tech)
1162 {
1163         int ret = 0;
1164
1165         dev_dbg(trf->dev, "rf technology: %d\n", tech);
1166
1167         switch (tech) {
1168         case NFC_DIGITAL_RF_TECH_106A:
1169                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443A_106;
1170                 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
1171                 trf->guard_time = TRF7970A_GUARD_TIME_NFCA;
1172                 break;
1173         case NFC_DIGITAL_RF_TECH_106B:
1174                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443B_106;
1175                 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
1176                 trf->guard_time = TRF7970A_GUARD_TIME_NFCB;
1177                 break;
1178         case NFC_DIGITAL_RF_TECH_212F:
1179                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_212;
1180                 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
1181                 trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1182                 break;
1183         case NFC_DIGITAL_RF_TECH_424F:
1184                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_424;
1185                 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
1186                 trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1187                 break;
1188         case NFC_DIGITAL_RF_TECH_ISO15693:
1189                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1190                 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
1191                 trf->guard_time = TRF7970A_GUARD_TIME_15693;
1192                 break;
1193         default:
1194                 dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1195                 return -EINVAL;
1196         }
1197
1198         trf->technology = tech;
1199
1200         /* If in initiator mode and not changing the RF tech due to a
1201          * PSL sequence (indicated by 'trf->iso_ctrl == 0xff' from
1202          * trf7970a_init()), clear the NFC Target Detection Level register
1203          * due to erratum.
1204          */
1205         if (trf->iso_ctrl == 0xff)
1206                 ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, 0);
1207
1208         return ret;
1209 }
1210
1211 static int trf7970a_is_rf_field(struct trf7970a *trf, bool *is_rf_field)
1212 {
1213         int ret;
1214         u8 rssi;
1215
1216         ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1217                         trf->chip_status_ctrl | TRF7970A_CHIP_STATUS_REC_ON);
1218         if (ret)
1219                 return ret;
1220
1221         ret = trf7970a_cmd(trf, TRF7970A_CMD_TEST_EXT_RF);
1222         if (ret)
1223                 return ret;
1224
1225         usleep_range(50, 60);
1226
1227         ret = trf7970a_read(trf, TRF7970A_RSSI_OSC_STATUS, &rssi);
1228         if (ret)
1229                 return ret;
1230
1231         ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1232                         trf->chip_status_ctrl);
1233         if (ret)
1234                 return ret;
1235
1236         if (rssi & TRF7970A_RSSI_OSC_STATUS_RSSI_MASK)
1237                 *is_rf_field = true;
1238         else
1239                 *is_rf_field = false;
1240
1241         return 0;
1242 }
1243
1244 static int trf7970a_in_config_framing(struct trf7970a *trf, int framing)
1245 {
1246         u8 iso_ctrl = trf->iso_ctrl_tech;
1247         bool is_rf_field = false;
1248         int ret;
1249
1250         dev_dbg(trf->dev, "framing: %d\n", framing);
1251
1252         switch (framing) {
1253         case NFC_DIGITAL_FRAMING_NFCA_SHORT:
1254         case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1255                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1256                 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1257                 break;
1258         case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1259         case NFC_DIGITAL_FRAMING_NFCA_T4T:
1260         case NFC_DIGITAL_FRAMING_NFCB:
1261         case NFC_DIGITAL_FRAMING_NFCB_T4T:
1262         case NFC_DIGITAL_FRAMING_NFCF:
1263         case NFC_DIGITAL_FRAMING_NFCF_T3T:
1264         case NFC_DIGITAL_FRAMING_ISO15693_INVENTORY:
1265         case NFC_DIGITAL_FRAMING_ISO15693_T5T:
1266         case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1267         case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1268                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1269                 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1270                 break;
1271         case NFC_DIGITAL_FRAMING_NFCA_T2T:
1272                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1273                 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1274                 break;
1275         default:
1276                 dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1277                 return -EINVAL;
1278         }
1279
1280         trf->framing = framing;
1281
1282         if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1283                 ret = trf7970a_is_rf_field(trf, &is_rf_field);
1284                 if (ret)
1285                         return ret;
1286
1287                 if (is_rf_field)
1288                         return -EBUSY;
1289         }
1290
1291         if (iso_ctrl != trf->iso_ctrl) {
1292                 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1293                 if (ret)
1294                         return ret;
1295
1296                 trf->iso_ctrl = iso_ctrl;
1297
1298                 ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1299                                 trf->modulator_sys_clk_ctrl);
1300                 if (ret)
1301                         return ret;
1302         }
1303
1304         if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1305                 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1306                                 trf->chip_status_ctrl |
1307                                         TRF7970A_CHIP_STATUS_RF_ON);
1308                 if (ret)
1309                         return ret;
1310
1311                 trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1312
1313                 usleep_range(trf->guard_time, trf->guard_time + 1000);
1314         }
1315
1316         return 0;
1317 }
1318
1319 static int trf7970a_in_configure_hw(struct nfc_digital_dev *ddev, int type,
1320                 int param)
1321 {
1322         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1323         int ret;
1324
1325         dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1326
1327         mutex_lock(&trf->lock);
1328
1329         trf->is_initiator = true;
1330
1331         if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1332                         (trf->state == TRF7970A_ST_RF_OFF)) {
1333                 ret = trf7970a_switch_rf_on(trf);
1334                 if (ret)
1335                         goto err_unlock;
1336         }
1337
1338         switch (type) {
1339         case NFC_DIGITAL_CONFIG_RF_TECH:
1340                 ret = trf7970a_in_config_rf_tech(trf, param);
1341                 break;
1342         case NFC_DIGITAL_CONFIG_FRAMING:
1343                 ret = trf7970a_in_config_framing(trf, param);
1344                 break;
1345         default:
1346                 dev_dbg(trf->dev, "Unknown type: %d\n", type);
1347                 ret = -EINVAL;
1348         }
1349
1350 err_unlock:
1351         mutex_unlock(&trf->lock);
1352         return ret;
1353 }
1354
1355 static int trf7970a_is_iso15693_write_or_lock(u8 cmd)
1356 {
1357         switch (cmd) {
1358         case ISO15693_CMD_WRITE_SINGLE_BLOCK:
1359         case ISO15693_CMD_LOCK_BLOCK:
1360         case ISO15693_CMD_WRITE_MULTIPLE_BLOCK:
1361         case ISO15693_CMD_WRITE_AFI:
1362         case ISO15693_CMD_LOCK_AFI:
1363         case ISO15693_CMD_WRITE_DSFID:
1364         case ISO15693_CMD_LOCK_DSFID:
1365                 return 1;
1366                 break;
1367         default:
1368                 return 0;
1369         }
1370 }
1371
1372 static int trf7970a_per_cmd_config(struct trf7970a *trf, struct sk_buff *skb)
1373 {
1374         u8 *req = skb->data;
1375         u8 special_fcn_reg1, iso_ctrl;
1376         int ret;
1377
1378         trf->issue_eof = false;
1379
1380         /* When issuing Type 2 read command, make sure the '4_bit_RX' bit in
1381          * special functions register 1 is cleared; otherwise, its a write or
1382          * sector select command and '4_bit_RX' must be set.
1383          *
1384          * When issuing an ISO 15693 command, inspect the flags byte to see
1385          * what speed to use.  Also, remember if the OPTION flag is set on
1386          * a Type 5 write or lock command so the driver will know that it
1387          * has to send an EOF in order to get a response.
1388          */
1389         if ((trf->technology == NFC_DIGITAL_RF_TECH_106A) &&
1390                         (trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T)) {
1391                 if (req[0] == NFC_T2T_CMD_READ)
1392                         special_fcn_reg1 = 0;
1393                 else
1394                         special_fcn_reg1 = TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX;
1395
1396                 if (special_fcn_reg1 != trf->special_fcn_reg1) {
1397                         ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1,
1398                                         special_fcn_reg1);
1399                         if (ret)
1400                                 return ret;
1401
1402                         trf->special_fcn_reg1 = special_fcn_reg1;
1403                 }
1404         } else if (trf->technology == NFC_DIGITAL_RF_TECH_ISO15693) {
1405                 iso_ctrl = trf->iso_ctrl & ~TRF7970A_ISO_CTRL_RFID_SPEED_MASK;
1406
1407                 switch (req[0] & ISO15693_REQ_FLAG_SPEED_MASK) {
1408                 case 0x00:
1409                         iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_662;
1410                         break;
1411                 case ISO15693_REQ_FLAG_SUB_CARRIER:
1412                         iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a;
1413                         break;
1414                 case ISO15693_REQ_FLAG_DATA_RATE:
1415                         iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1416                         break;
1417                 case (ISO15693_REQ_FLAG_SUB_CARRIER |
1418                                 ISO15693_REQ_FLAG_DATA_RATE):
1419                         iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669;
1420                         break;
1421                 }
1422
1423                 if (iso_ctrl != trf->iso_ctrl) {
1424                         ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1425                         if (ret)
1426                                 return ret;
1427
1428                         trf->iso_ctrl = iso_ctrl;
1429                 }
1430
1431                 if ((trf->framing == NFC_DIGITAL_FRAMING_ISO15693_T5T) &&
1432                                 trf7970a_is_iso15693_write_or_lock(req[1]) &&
1433                                 (req[0] & ISO15693_REQ_FLAG_OPTION))
1434                         trf->issue_eof = true;
1435         }
1436
1437         return 0;
1438 }
1439
1440 static int trf7970a_send_cmd(struct nfc_digital_dev *ddev,
1441                 struct sk_buff *skb, u16 timeout,
1442                 nfc_digital_cmd_complete_t cb, void *arg)
1443 {
1444         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1445         u8 prefix[5];
1446         unsigned int len;
1447         int ret;
1448         u8 status;
1449
1450         dev_dbg(trf->dev, "New request - state: %d, timeout: %d ms, len: %d\n",
1451                         trf->state, timeout, skb->len);
1452
1453         if (skb->len > TRF7970A_TX_MAX)
1454                 return -EINVAL;
1455
1456         mutex_lock(&trf->lock);
1457
1458         if ((trf->state != TRF7970A_ST_IDLE) &&
1459                         (trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1460                 dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1461                                 trf->state);
1462                 ret = -EIO;
1463                 goto out_err;
1464         }
1465
1466         if (trf->aborting) {
1467                 dev_dbg(trf->dev, "Abort process complete\n");
1468                 trf->aborting = false;
1469                 ret = -ECANCELED;
1470                 goto out_err;
1471         }
1472
1473         if (timeout) {
1474                 trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1475                                 GFP_KERNEL);
1476                 if (!trf->rx_skb) {
1477                         dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1478                         ret = -ENOMEM;
1479                         goto out_err;
1480                 }
1481         }
1482
1483         if (trf->state == TRF7970A_ST_IDLE_RX_BLOCKED) {
1484                 ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1485                 if (ret)
1486                         goto out_err;
1487
1488                 trf->state = TRF7970A_ST_IDLE;
1489         }
1490
1491         if (trf->is_initiator) {
1492                 ret = trf7970a_per_cmd_config(trf, skb);
1493                 if (ret)
1494                         goto out_err;
1495         }
1496
1497         trf->ddev = ddev;
1498         trf->tx_skb = skb;
1499         trf->cb = cb;
1500         trf->cb_arg = arg;
1501         trf->timeout = timeout;
1502         trf->ignore_timeout = false;
1503
1504         len = skb->len;
1505
1506         /* TX data must be prefixed with a FIFO reset cmd, a cmd that depends
1507          * on what the current framing is, the address of the TX length byte 1
1508          * register (0x1d), and the 2 byte length of the data to be transmitted.
1509          * That totals 5 bytes.
1510          */
1511         prefix[0] = TRF7970A_CMD_BIT_CTRL |
1512                         TRF7970A_CMD_BIT_OPCODE(TRF7970A_CMD_FIFO_RESET);
1513         prefix[1] = TRF7970A_CMD_BIT_CTRL |
1514                         TRF7970A_CMD_BIT_OPCODE(trf->tx_cmd);
1515         prefix[2] = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_TX_LENGTH_BYTE1;
1516
1517         if (trf->framing == NFC_DIGITAL_FRAMING_NFCA_SHORT) {
1518                 prefix[3] = 0x00;
1519                 prefix[4] = 0x0f; /* 7 bits */
1520         } else {
1521                 prefix[3] = (len & 0xf00) >> 4;
1522                 prefix[3] |= ((len & 0xf0) >> 4);
1523                 prefix[4] = ((len & 0x0f) << 4);
1524         }
1525
1526         len = min_t(int, skb->len, TRF7970A_FIFO_SIZE);
1527
1528         /* Clear possible spurious interrupt */
1529         ret = trf7970a_read_irqstatus(trf, &status);
1530         if (ret)
1531                 goto out_err;
1532
1533         ret = trf7970a_transmit(trf, skb, len, prefix, sizeof(prefix));
1534         if (ret) {
1535                 kfree_skb(trf->rx_skb);
1536                 trf->rx_skb = NULL;
1537         }
1538
1539 out_err:
1540         mutex_unlock(&trf->lock);
1541         return ret;
1542 }
1543
1544 static int trf7970a_tg_config_rf_tech(struct trf7970a *trf, int tech)
1545 {
1546         int ret = 0;
1547
1548         dev_dbg(trf->dev, "rf technology: %d\n", tech);
1549
1550         switch (tech) {
1551         case NFC_DIGITAL_RF_TECH_106A:
1552                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1553                         TRF7970A_ISO_CTRL_NFC_CE |
1554                         TRF7970A_ISO_CTRL_NFC_CE_14443A;
1555                 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
1556                 break;
1557         case NFC_DIGITAL_RF_TECH_212F:
1558                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1559                         TRF7970A_ISO_CTRL_NFC_NFCF_212;
1560                 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
1561                 break;
1562         case NFC_DIGITAL_RF_TECH_424F:
1563                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1564                         TRF7970A_ISO_CTRL_NFC_NFCF_424;
1565                 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
1566                 break;
1567         default:
1568                 dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1569                 return -EINVAL;
1570         }
1571
1572         trf->technology = tech;
1573
1574         /* Normally we write the ISO_CTRL register in
1575          * trf7970a_tg_config_framing() because the framing can change
1576          * the value written.  However, when sending a PSL RES,
1577          * digital_tg_send_psl_res_complete() doesn't call
1578          * trf7970a_tg_config_framing() so we must write the register
1579          * here.
1580          */
1581         if ((trf->framing == NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED) &&
1582                         (trf->iso_ctrl_tech != trf->iso_ctrl)) {
1583                 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
1584                                 trf->iso_ctrl_tech);
1585
1586                 trf->iso_ctrl = trf->iso_ctrl_tech;
1587         }
1588
1589         return ret;
1590 }
1591
1592 /* Since this is a target routine, several of the framing calls are
1593  * made between receiving the request and sending the response so they
1594  * should take effect until after the response is sent.  This is accomplished
1595  * by skipping the ISO_CTRL register write here and doing it in the interrupt
1596  * handler.
1597  */
1598 static int trf7970a_tg_config_framing(struct trf7970a *trf, int framing)
1599 {
1600         u8 iso_ctrl = trf->iso_ctrl_tech;
1601         int ret;
1602
1603         dev_dbg(trf->dev, "framing: %d\n", framing);
1604
1605         switch (framing) {
1606         case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1607                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1608                 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1609                 break;
1610         case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1611         case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1612         case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
1613                 /* These ones are applied in the interrupt handler */
1614                 iso_ctrl = trf->iso_ctrl; /* Don't write to ISO_CTRL yet */
1615                 break;
1616         case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1617                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1618                 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1619                 break;
1620         case NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED:
1621                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1622                 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1623                 break;
1624         default:
1625                 dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1626                 return -EINVAL;
1627         }
1628
1629         trf->framing = framing;
1630
1631         if (iso_ctrl != trf->iso_ctrl) {
1632                 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1633                 if (ret)
1634                         return ret;
1635
1636                 trf->iso_ctrl = iso_ctrl;
1637
1638                 ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1639                                 trf->modulator_sys_clk_ctrl);
1640                 if (ret)
1641                         return ret;
1642         }
1643
1644         if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1645                 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1646                                 trf->chip_status_ctrl |
1647                                         TRF7970A_CHIP_STATUS_RF_ON);
1648                 if (ret)
1649                         return ret;
1650
1651                 trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1652         }
1653
1654         return 0;
1655 }
1656
1657 static int trf7970a_tg_configure_hw(struct nfc_digital_dev *ddev, int type,
1658                 int param)
1659 {
1660         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1661         int ret;
1662
1663         dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1664
1665         mutex_lock(&trf->lock);
1666
1667         trf->is_initiator = false;
1668
1669         if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1670                         (trf->state == TRF7970A_ST_RF_OFF)) {
1671                 ret = trf7970a_switch_rf_on(trf);
1672                 if (ret)
1673                         goto err_unlock;
1674         }
1675
1676         switch (type) {
1677         case NFC_DIGITAL_CONFIG_RF_TECH:
1678                 ret = trf7970a_tg_config_rf_tech(trf, param);
1679                 break;
1680         case NFC_DIGITAL_CONFIG_FRAMING:
1681                 ret = trf7970a_tg_config_framing(trf, param);
1682                 break;
1683         default:
1684                 dev_dbg(trf->dev, "Unknown type: %d\n", type);
1685                 ret = -EINVAL;
1686         }
1687
1688 err_unlock:
1689         mutex_unlock(&trf->lock);
1690         return ret;
1691 }
1692
1693 static int _trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1694                 nfc_digital_cmd_complete_t cb, void *arg, bool mode_detect)
1695 {
1696         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1697         int ret;
1698
1699         mutex_lock(&trf->lock);
1700
1701         if ((trf->state != TRF7970A_ST_IDLE) &&
1702                         (trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1703                 dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1704                                 trf->state);
1705                 ret = -EIO;
1706                 goto out_err;
1707         }
1708
1709         if (trf->aborting) {
1710                 dev_dbg(trf->dev, "Abort process complete\n");
1711                 trf->aborting = false;
1712                 ret = -ECANCELED;
1713                 goto out_err;
1714         }
1715
1716         trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1717                         GFP_KERNEL);
1718         if (!trf->rx_skb) {
1719                 dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1720                 ret = -ENOMEM;
1721                 goto out_err;
1722         }
1723
1724         ret = trf7970a_write(trf, TRF7970A_RX_SPECIAL_SETTINGS,
1725                         TRF7970A_RX_SPECIAL_SETTINGS_HBT |
1726                         TRF7970A_RX_SPECIAL_SETTINGS_M848 |
1727                         TRF7970A_RX_SPECIAL_SETTINGS_C424 |
1728                         TRF7970A_RX_SPECIAL_SETTINGS_C212);
1729         if (ret)
1730                 return ret;
1731
1732         ret = trf7970a_write(trf, TRF7970A_REG_IO_CTRL,
1733                         TRF7970A_REG_IO_CTRL_VRS(0x1));
1734         if (ret)
1735                 return ret;
1736
1737         ret = trf7970a_write(trf, TRF7970A_NFC_LOW_FIELD_LEVEL,
1738                         TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(0x3));
1739         if (ret)
1740                 return ret;
1741
1742         ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL,
1743                         TRF7970A_NFC_TARGET_LEVEL_RFDET(0x7));
1744         if (ret)
1745                 return ret;
1746
1747         trf->ddev = ddev;
1748         trf->cb = cb;
1749         trf->cb_arg = arg;
1750         trf->timeout = timeout;
1751         trf->ignore_timeout = false;
1752
1753         ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1754         if (ret)
1755                 goto out_err;
1756
1757         trf->state = mode_detect ? TRF7970A_ST_LISTENING_MD :
1758                                    TRF7970A_ST_LISTENING;
1759
1760         schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
1761
1762 out_err:
1763         mutex_unlock(&trf->lock);
1764         return ret;
1765 }
1766
1767 static int trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1768                 nfc_digital_cmd_complete_t cb, void *arg)
1769 {
1770         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1771
1772         dev_dbg(trf->dev, "Listen - state: %d, timeout: %d ms\n",
1773                         trf->state, timeout);
1774
1775         return _trf7970a_tg_listen(ddev, timeout, cb, arg, false);
1776 }
1777
1778 static int trf7970a_tg_listen_md(struct nfc_digital_dev *ddev,
1779                 u16 timeout, nfc_digital_cmd_complete_t cb, void *arg)
1780 {
1781         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1782         int ret;
1783
1784         dev_dbg(trf->dev, "Listen MD - state: %d, timeout: %d ms\n",
1785                         trf->state, timeout);
1786
1787         ret = trf7970a_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
1788                         NFC_DIGITAL_RF_TECH_106A);
1789         if (ret)
1790                 return ret;
1791
1792         ret = trf7970a_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1793                         NFC_DIGITAL_FRAMING_NFCA_NFC_DEP);
1794         if (ret)
1795                 return ret;
1796
1797         return _trf7970a_tg_listen(ddev, timeout, cb, arg, true);
1798 }
1799
1800 static int trf7970a_tg_get_rf_tech(struct nfc_digital_dev *ddev, u8 *rf_tech)
1801 {
1802         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1803
1804         dev_dbg(trf->dev, "Get RF Tech - state: %d, rf_tech: %d\n",
1805                         trf->state, trf->md_rf_tech);
1806
1807         *rf_tech = trf->md_rf_tech;
1808
1809         return 0;
1810 }
1811
1812 static void trf7970a_abort_cmd(struct nfc_digital_dev *ddev)
1813 {
1814         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1815
1816         dev_dbg(trf->dev, "Abort process initiated\n");
1817
1818         mutex_lock(&trf->lock);
1819
1820         switch (trf->state) {
1821         case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1822         case TRF7970A_ST_WAIT_FOR_RX_DATA:
1823         case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1824         case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1825                 trf->aborting = true;
1826                 break;
1827         case TRF7970A_ST_LISTENING:
1828                 trf->ignore_timeout = !cancel_delayed_work(&trf->timeout_work);
1829                 trf7970a_send_err_upstream(trf, -ECANCELED);
1830                 dev_dbg(trf->dev, "Abort process complete\n");
1831                 break;
1832         default:
1833                 break;
1834         }
1835
1836         mutex_unlock(&trf->lock);
1837 }
1838
1839 static struct nfc_digital_ops trf7970a_nfc_ops = {
1840         .in_configure_hw        = trf7970a_in_configure_hw,
1841         .in_send_cmd            = trf7970a_send_cmd,
1842         .tg_configure_hw        = trf7970a_tg_configure_hw,
1843         .tg_send_cmd            = trf7970a_send_cmd,
1844         .tg_listen              = trf7970a_tg_listen,
1845         .tg_listen_md           = trf7970a_tg_listen_md,
1846         .tg_get_rf_tech         = trf7970a_tg_get_rf_tech,
1847         .switch_rf              = trf7970a_switch_rf,
1848         .abort_cmd              = trf7970a_abort_cmd,
1849 };
1850
1851 static int trf7970a_power_up(struct trf7970a *trf)
1852 {
1853         int ret;
1854
1855         dev_dbg(trf->dev, "Powering up - state: %d\n", trf->state);
1856
1857         if (trf->state != TRF7970A_ST_PWR_OFF)
1858                 return 0;
1859
1860         ret = regulator_enable(trf->regulator);
1861         if (ret) {
1862                 dev_err(trf->dev, "%s - Can't enable VIN: %d\n", __func__, ret);
1863                 return ret;
1864         }
1865
1866         usleep_range(5000, 6000);
1867
1868         if (!(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW)) {
1869                 gpio_set_value(trf->en2_gpio, 1);
1870                 usleep_range(1000, 2000);
1871         }
1872
1873         gpio_set_value(trf->en_gpio, 1);
1874
1875         usleep_range(20000, 21000);
1876
1877         trf->state = TRF7970A_ST_RF_OFF;
1878
1879         return 0;
1880 }
1881
1882 static int trf7970a_power_down(struct trf7970a *trf)
1883 {
1884         int ret;
1885
1886         dev_dbg(trf->dev, "Powering down - state: %d\n", trf->state);
1887
1888         if (trf->state == TRF7970A_ST_PWR_OFF)
1889                 return 0;
1890
1891         if (trf->state != TRF7970A_ST_RF_OFF) {
1892                 dev_dbg(trf->dev, "Can't power down - not RF_OFF state (%d)\n",
1893                                 trf->state);
1894                 return -EBUSY;
1895         }
1896
1897         gpio_set_value(trf->en_gpio, 0);
1898         gpio_set_value(trf->en2_gpio, 0);
1899
1900         ret = regulator_disable(trf->regulator);
1901         if (ret)
1902                 dev_err(trf->dev, "%s - Can't disable VIN: %d\n", __func__,
1903                                 ret);
1904
1905         trf->state = TRF7970A_ST_PWR_OFF;
1906
1907         return ret;
1908 }
1909
1910 static int trf7970a_startup(struct trf7970a *trf)
1911 {
1912         int ret;
1913
1914         ret = trf7970a_power_up(trf);
1915         if (ret)
1916                 return ret;
1917
1918         pm_runtime_set_active(trf->dev);
1919         pm_runtime_enable(trf->dev);
1920         pm_runtime_mark_last_busy(trf->dev);
1921
1922         return 0;
1923 }
1924
1925 static void trf7970a_shutdown(struct trf7970a *trf)
1926 {
1927         switch (trf->state) {
1928         case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1929         case TRF7970A_ST_WAIT_FOR_RX_DATA:
1930         case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1931         case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1932         case TRF7970A_ST_LISTENING:
1933                 trf7970a_send_err_upstream(trf, -ECANCELED);
1934                 /* FALLTHROUGH */
1935         case TRF7970A_ST_IDLE:
1936         case TRF7970A_ST_IDLE_RX_BLOCKED:
1937                 trf7970a_switch_rf_off(trf);
1938                 break;
1939         default:
1940                 break;
1941         }
1942
1943         pm_runtime_disable(trf->dev);
1944         pm_runtime_set_suspended(trf->dev);
1945
1946         trf7970a_power_down(trf);
1947 }
1948
1949 static int trf7970a_get_autosuspend_delay(struct device_node *np)
1950 {
1951         int autosuspend_delay, ret;
1952
1953         ret = of_property_read_u32(np, "autosuspend-delay", &autosuspend_delay);
1954         if (ret)
1955                 autosuspend_delay = TRF7970A_AUTOSUSPEND_DELAY;
1956
1957         return autosuspend_delay;
1958 }
1959
1960 static int trf7970a_get_vin_voltage_override(struct device_node *np,
1961                 u32 *vin_uvolts)
1962 {
1963         return of_property_read_u32(np, "vin-voltage-override", vin_uvolts);
1964 }
1965
1966 static int trf7970a_probe(struct spi_device *spi)
1967 {
1968         struct device_node *np = spi->dev.of_node;
1969         struct trf7970a *trf;
1970         int uvolts, autosuspend_delay, ret;
1971
1972         if (!np) {
1973                 dev_err(&spi->dev, "No Device Tree entry\n");
1974                 return -EINVAL;
1975         }
1976
1977         trf = devm_kzalloc(&spi->dev, sizeof(*trf), GFP_KERNEL);
1978         if (!trf)
1979                 return -ENOMEM;
1980
1981         trf->state = TRF7970A_ST_PWR_OFF;
1982         trf->dev = &spi->dev;
1983         trf->spi = spi;
1984
1985         spi->mode = SPI_MODE_1;
1986         spi->bits_per_word = 8;
1987
1988         ret = spi_setup(spi);
1989         if (ret < 0) {
1990                 dev_err(trf->dev, "Can't set up SPI Communication\n");
1991                 return ret;
1992         }
1993
1994         if (of_property_read_bool(np, "irq-status-read-quirk"))
1995                 trf->quirks |= TRF7970A_QUIRK_IRQ_STATUS_READ;
1996
1997         /* There are two enable pins - both must be present */
1998         trf->en_gpio = of_get_named_gpio(np, "ti,enable-gpios", 0);
1999         if (!gpio_is_valid(trf->en_gpio)) {
2000                 dev_err(trf->dev, "No EN GPIO property\n");
2001                 return trf->en_gpio;
2002         }
2003
2004         ret = devm_gpio_request_one(trf->dev, trf->en_gpio,
2005                         GPIOF_DIR_OUT | GPIOF_INIT_LOW, "trf7970a EN");
2006         if (ret) {
2007                 dev_err(trf->dev, "Can't request EN GPIO: %d\n", ret);
2008                 return ret;
2009         }
2010
2011         trf->en2_gpio = of_get_named_gpio(np, "ti,enable-gpios", 1);
2012         if (!gpio_is_valid(trf->en2_gpio)) {
2013                 dev_err(trf->dev, "No EN2 GPIO property\n");
2014                 return trf->en2_gpio;
2015         }
2016
2017         ret = devm_gpio_request_one(trf->dev, trf->en2_gpio,
2018                         GPIOF_DIR_OUT | GPIOF_INIT_LOW, "trf7970a EN2");
2019         if (ret) {
2020                 dev_err(trf->dev, "Can't request EN2 GPIO: %d\n", ret);
2021                 return ret;
2022         }
2023
2024         if (of_property_read_bool(np, "en2-rf-quirk"))
2025                 trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW;
2026
2027         ret = devm_request_threaded_irq(trf->dev, spi->irq, NULL,
2028                         trf7970a_irq, IRQF_TRIGGER_RISING | IRQF_ONESHOT,
2029                         "trf7970a", trf);
2030         if (ret) {
2031                 dev_err(trf->dev, "Can't request IRQ#%d: %d\n", spi->irq, ret);
2032                 return ret;
2033         }
2034
2035         mutex_init(&trf->lock);
2036         INIT_DELAYED_WORK(&trf->timeout_work, trf7970a_timeout_work_handler);
2037
2038         trf->regulator = devm_regulator_get(&spi->dev, "vin");
2039         if (IS_ERR(trf->regulator)) {
2040                 ret = PTR_ERR(trf->regulator);
2041                 dev_err(trf->dev, "Can't get VIN regulator: %d\n", ret);
2042                 goto err_destroy_lock;
2043         }
2044
2045         ret = regulator_enable(trf->regulator);
2046         if (ret) {
2047                 dev_err(trf->dev, "Can't enable VIN: %d\n", ret);
2048                 goto err_destroy_lock;
2049         }
2050
2051         ret = trf7970a_get_vin_voltage_override(np, &uvolts);
2052         if (ret)
2053                 uvolts = regulator_get_voltage(trf->regulator);
2054
2055         if (uvolts > 4000000)
2056                 trf->chip_status_ctrl = TRF7970A_CHIP_STATUS_VRS5_3;
2057
2058         trf->ddev = nfc_digital_allocate_device(&trf7970a_nfc_ops,
2059                         TRF7970A_SUPPORTED_PROTOCOLS,
2060                         NFC_DIGITAL_DRV_CAPS_IN_CRC |
2061                                 NFC_DIGITAL_DRV_CAPS_TG_CRC, 0, 0);
2062         if (!trf->ddev) {
2063                 dev_err(trf->dev, "Can't allocate NFC digital device\n");
2064                 ret = -ENOMEM;
2065                 goto err_disable_regulator;
2066         }
2067
2068         nfc_digital_set_parent_dev(trf->ddev, trf->dev);
2069         nfc_digital_set_drvdata(trf->ddev, trf);
2070         spi_set_drvdata(spi, trf);
2071
2072         autosuspend_delay = trf7970a_get_autosuspend_delay(np);
2073
2074         pm_runtime_set_autosuspend_delay(trf->dev, autosuspend_delay);
2075         pm_runtime_use_autosuspend(trf->dev);
2076
2077         ret = trf7970a_startup(trf);
2078         if (ret)
2079                 goto err_free_ddev;
2080
2081         ret = nfc_digital_register_device(trf->ddev);
2082         if (ret) {
2083                 dev_err(trf->dev, "Can't register NFC digital device: %d\n",
2084                                 ret);
2085                 goto err_shutdown;
2086         }
2087
2088         return 0;
2089
2090 err_shutdown:
2091         trf7970a_shutdown(trf);
2092 err_free_ddev:
2093         nfc_digital_free_device(trf->ddev);
2094 err_disable_regulator:
2095         regulator_disable(trf->regulator);
2096 err_destroy_lock:
2097         mutex_destroy(&trf->lock);
2098         return ret;
2099 }
2100
2101 static int trf7970a_remove(struct spi_device *spi)
2102 {
2103         struct trf7970a *trf = spi_get_drvdata(spi);
2104
2105         mutex_lock(&trf->lock);
2106
2107         trf7970a_shutdown(trf);
2108
2109         mutex_unlock(&trf->lock);
2110
2111         nfc_digital_unregister_device(trf->ddev);
2112         nfc_digital_free_device(trf->ddev);
2113
2114         regulator_disable(trf->regulator);
2115
2116         mutex_destroy(&trf->lock);
2117
2118         return 0;
2119 }
2120
2121 #ifdef CONFIG_PM_SLEEP
2122 static int trf7970a_suspend(struct device *dev)
2123 {
2124         struct spi_device *spi = container_of(dev, struct spi_device, dev);
2125         struct trf7970a *trf = spi_get_drvdata(spi);
2126
2127         dev_dbg(dev, "Suspend\n");
2128
2129         mutex_lock(&trf->lock);
2130
2131         trf7970a_shutdown(trf);
2132
2133         mutex_unlock(&trf->lock);
2134
2135         return 0;
2136 }
2137
2138 static int trf7970a_resume(struct device *dev)
2139 {
2140         struct spi_device *spi = container_of(dev, struct spi_device, dev);
2141         struct trf7970a *trf = spi_get_drvdata(spi);
2142         int ret;
2143
2144         dev_dbg(dev, "Resume\n");
2145
2146         mutex_lock(&trf->lock);
2147
2148         ret = trf7970a_startup(trf);
2149
2150         mutex_unlock(&trf->lock);
2151
2152         return ret;
2153 }
2154 #endif
2155
2156 #ifdef CONFIG_PM_RUNTIME
2157 static int trf7970a_pm_runtime_suspend(struct device *dev)
2158 {
2159         struct spi_device *spi = container_of(dev, struct spi_device, dev);
2160         struct trf7970a *trf = spi_get_drvdata(spi);
2161         int ret;
2162
2163         dev_dbg(dev, "Runtime suspend\n");
2164
2165         mutex_lock(&trf->lock);
2166
2167         ret = trf7970a_power_down(trf);
2168
2169         mutex_unlock(&trf->lock);
2170
2171         return ret;
2172 }
2173
2174 static int trf7970a_pm_runtime_resume(struct device *dev)
2175 {
2176         struct spi_device *spi = container_of(dev, struct spi_device, dev);
2177         struct trf7970a *trf = spi_get_drvdata(spi);
2178         int ret;
2179
2180         dev_dbg(dev, "Runtime resume\n");
2181
2182         ret = trf7970a_power_up(trf);
2183         if (!ret)
2184                 pm_runtime_mark_last_busy(dev);
2185
2186         return ret;
2187 }
2188 #endif
2189
2190 static const struct dev_pm_ops trf7970a_pm_ops = {
2191         SET_SYSTEM_SLEEP_PM_OPS(trf7970a_suspend, trf7970a_resume)
2192         SET_RUNTIME_PM_OPS(trf7970a_pm_runtime_suspend,
2193                         trf7970a_pm_runtime_resume, NULL)
2194 };
2195
2196 static const struct spi_device_id trf7970a_id_table[] = {
2197         { "trf7970a", 0 },
2198         { }
2199 };
2200 MODULE_DEVICE_TABLE(spi, trf7970a_id_table);
2201
2202 static struct spi_driver trf7970a_spi_driver = {
2203         .probe          = trf7970a_probe,
2204         .remove         = trf7970a_remove,
2205         .id_table       = trf7970a_id_table,
2206         .driver         = {
2207                 .name   = "trf7970a",
2208                 .owner  = THIS_MODULE,
2209                 .pm     = &trf7970a_pm_ops,
2210         },
2211 };
2212
2213 module_spi_driver(trf7970a_spi_driver);
2214
2215 MODULE_AUTHOR("Mark A. Greer <mgreer@animalcreek.com>");
2216 MODULE_LICENSE("GPL v2");
2217 MODULE_DESCRIPTION("TI trf7970a RFID/NFC Transceiver Driver");