2 * Driver for Microchip MRF24J40 802.15.4 Wireless-PAN Networking controller
4 * Copyright (C) 2012 Alan Ott <alan@signal11.us>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
18 #include <linux/spi/spi.h>
19 #include <linux/interrupt.h>
20 #include <linux/module.h>
21 #include <linux/ieee802154.h>
22 #include <net/cfg802154.h>
23 #include <net/mac802154.h>
25 /* MRF24J40 Short Address Registers */
26 #define REG_RXMCR 0x00 /* Receive MAC control */
27 #define REG_PANIDL 0x01 /* PAN ID (low) */
28 #define REG_PANIDH 0x02 /* PAN ID (high) */
29 #define REG_SADRL 0x03 /* Short address (low) */
30 #define REG_SADRH 0x04 /* Short address (high) */
31 #define REG_EADR0 0x05 /* Long address (low) (high is EADR7) */
32 #define REG_TXMCR 0x11 /* Transmit MAC control */
33 #define REG_PACON0 0x16 /* Power Amplifier Control */
34 #define REG_PACON1 0x17 /* Power Amplifier Control */
35 #define REG_PACON2 0x18 /* Power Amplifier Control */
36 #define REG_TXNCON 0x1B /* Transmit Normal FIFO Control */
37 #define REG_TXSTAT 0x24 /* TX MAC Status Register */
38 #define REG_SOFTRST 0x2A /* Soft Reset */
39 #define REG_TXSTBL 0x2E /* TX Stabilization */
40 #define REG_INTSTAT 0x31 /* Interrupt Status */
41 #define REG_INTCON 0x32 /* Interrupt Control */
42 #define REG_GPIO 0x33 /* GPIO */
43 #define REG_TRISGPIO 0x34 /* GPIO direction */
44 #define REG_RFCTL 0x36 /* RF Control Mode Register */
45 #define REG_BBREG1 0x39 /* Baseband Registers */
46 #define REG_BBREG2 0x3A /* */
47 #define REG_BBREG6 0x3E /* */
48 #define REG_CCAEDTH 0x3F /* Energy Detection Threshold */
50 /* MRF24J40 Long Address Registers */
51 #define REG_RFCON0 0x200 /* RF Control Registers */
52 #define REG_RFCON1 0x201
53 #define REG_RFCON2 0x202
54 #define REG_RFCON3 0x203
55 #define REG_RFCON5 0x205
56 #define REG_RFCON6 0x206
57 #define REG_RFCON7 0x207
58 #define REG_RFCON8 0x208
59 #define REG_RSSI 0x210
60 #define REG_SLPCON0 0x211 /* Sleep Clock Control Registers */
61 #define REG_SLPCON1 0x220
62 #define REG_WAKETIMEL 0x222 /* Wake-up Time Match Value Low */
63 #define REG_WAKETIMEH 0x223 /* Wake-up Time Match Value High */
64 #define REG_TESTMODE 0x22F /* Test mode */
65 #define REG_RX_FIFO 0x300 /* Receive FIFO */
67 /* Device configuration: Only channels 11-26 on page 0 are supported. */
68 #define MRF24J40_CHAN_MIN 11
69 #define MRF24J40_CHAN_MAX 26
70 #define CHANNEL_MASK (((u32)1 << (MRF24J40_CHAN_MAX + 1)) \
71 - ((u32)1 << MRF24J40_CHAN_MIN))
73 #define TX_FIFO_SIZE 128 /* From datasheet */
74 #define RX_FIFO_SIZE 144 /* From datasheet */
75 #define SET_CHANNEL_DELAY_US 192 /* From datasheet */
77 enum mrf24j40_modules { MRF24J40, MRF24J40MA, MRF24J40MC };
79 /* Device Private Data */
81 struct spi_device *spi;
82 struct ieee802154_hw *hw;
84 struct mutex buffer_mutex; /* only used to protect buf */
85 struct completion tx_complete;
86 u8 *buf; /* 3 bytes. Used for SPI single-register transfers. */
89 /* Read/Write SPI Commands for Short and Long Address registers. */
90 #define MRF24J40_READSHORT(reg) ((reg) << 1)
91 #define MRF24J40_WRITESHORT(reg) ((reg) << 1 | 1)
92 #define MRF24J40_READLONG(reg) (1 << 15 | (reg) << 5)
93 #define MRF24J40_WRITELONG(reg) (1 << 15 | (reg) << 5 | 1 << 4)
95 /* The datasheet indicates the theoretical maximum for SCK to be 10MHz */
96 #define MAX_SPI_SPEED_HZ 10000000
98 #define printdev(X) (&X->spi->dev)
100 static int write_short_reg(struct mrf24j40 *devrec, u8 reg, u8 value)
103 struct spi_message msg;
104 struct spi_transfer xfer = {
106 .tx_buf = devrec->buf,
107 .rx_buf = devrec->buf,
110 spi_message_init(&msg);
111 spi_message_add_tail(&xfer, &msg);
113 mutex_lock(&devrec->buffer_mutex);
114 devrec->buf[0] = MRF24J40_WRITESHORT(reg);
115 devrec->buf[1] = value;
117 ret = spi_sync(devrec->spi, &msg);
119 dev_err(printdev(devrec),
120 "SPI write Failed for short register 0x%hhx\n", reg);
122 mutex_unlock(&devrec->buffer_mutex);
126 static int read_short_reg(struct mrf24j40 *devrec, u8 reg, u8 *val)
129 struct spi_message msg;
130 struct spi_transfer xfer = {
132 .tx_buf = devrec->buf,
133 .rx_buf = devrec->buf,
136 spi_message_init(&msg);
137 spi_message_add_tail(&xfer, &msg);
139 mutex_lock(&devrec->buffer_mutex);
140 devrec->buf[0] = MRF24J40_READSHORT(reg);
143 ret = spi_sync(devrec->spi, &msg);
145 dev_err(printdev(devrec),
146 "SPI read Failed for short register 0x%hhx\n", reg);
148 *val = devrec->buf[1];
150 mutex_unlock(&devrec->buffer_mutex);
154 static int read_long_reg(struct mrf24j40 *devrec, u16 reg, u8 *value)
158 struct spi_message msg;
159 struct spi_transfer xfer = {
161 .tx_buf = devrec->buf,
162 .rx_buf = devrec->buf,
165 spi_message_init(&msg);
166 spi_message_add_tail(&xfer, &msg);
168 cmd = MRF24J40_READLONG(reg);
169 mutex_lock(&devrec->buffer_mutex);
170 devrec->buf[0] = cmd >> 8 & 0xff;
171 devrec->buf[1] = cmd & 0xff;
174 ret = spi_sync(devrec->spi, &msg);
176 dev_err(printdev(devrec),
177 "SPI read Failed for long register 0x%hx\n", reg);
179 *value = devrec->buf[2];
181 mutex_unlock(&devrec->buffer_mutex);
185 static int write_long_reg(struct mrf24j40 *devrec, u16 reg, u8 val)
189 struct spi_message msg;
190 struct spi_transfer xfer = {
192 .tx_buf = devrec->buf,
193 .rx_buf = devrec->buf,
196 spi_message_init(&msg);
197 spi_message_add_tail(&xfer, &msg);
199 cmd = MRF24J40_WRITELONG(reg);
200 mutex_lock(&devrec->buffer_mutex);
201 devrec->buf[0] = cmd >> 8 & 0xff;
202 devrec->buf[1] = cmd & 0xff;
203 devrec->buf[2] = val;
205 ret = spi_sync(devrec->spi, &msg);
207 dev_err(printdev(devrec),
208 "SPI write Failed for long register 0x%hx\n", reg);
210 mutex_unlock(&devrec->buffer_mutex);
214 /* This function relies on an undocumented write method. Once a write command
215 and address is set, as many bytes of data as desired can be clocked into
216 the device. The datasheet only shows setting one byte at a time. */
217 static int write_tx_buf(struct mrf24j40 *devrec, u16 reg,
218 const u8 *data, size_t length)
223 struct spi_message msg;
224 struct spi_transfer addr_xfer = {
226 .tx_buf = devrec->buf,
228 struct spi_transfer lengths_xfer = {
230 .tx_buf = &lengths, /* TODO: Is DMA really required for SPI? */
232 struct spi_transfer data_xfer = {
237 /* Range check the length. 2 bytes are used for the length fields.*/
238 if (length > TX_FIFO_SIZE-2) {
239 dev_err(printdev(devrec), "write_tx_buf() was passed too large a buffer. Performing short write.\n");
240 length = TX_FIFO_SIZE-2;
243 spi_message_init(&msg);
244 spi_message_add_tail(&addr_xfer, &msg);
245 spi_message_add_tail(&lengths_xfer, &msg);
246 spi_message_add_tail(&data_xfer, &msg);
248 cmd = MRF24J40_WRITELONG(reg);
249 mutex_lock(&devrec->buffer_mutex);
250 devrec->buf[0] = cmd >> 8 & 0xff;
251 devrec->buf[1] = cmd & 0xff;
252 lengths[0] = 0x0; /* Header Length. Set to 0 for now. TODO */
253 lengths[1] = length; /* Total length */
255 ret = spi_sync(devrec->spi, &msg);
257 dev_err(printdev(devrec), "SPI write Failed for TX buf\n");
259 mutex_unlock(&devrec->buffer_mutex);
263 static int mrf24j40_read_rx_buf(struct mrf24j40 *devrec,
264 u8 *data, u8 *len, u8 *lqi)
271 struct spi_message msg;
272 struct spi_transfer addr_xfer = {
276 struct spi_transfer data_xfer = {
277 .len = 0x0, /* set below */
280 struct spi_transfer status_xfer = {
285 /* Get the length of the data in the RX FIFO. The length in this
286 * register exclues the 1-byte length field at the beginning. */
287 ret = read_long_reg(devrec, REG_RX_FIFO, &rx_len);
291 /* Range check the RX FIFO length, accounting for the one-byte
292 * length field at the beginning. */
293 if (rx_len > RX_FIFO_SIZE-1) {
294 dev_err(printdev(devrec), "Invalid length read from device. Performing short read.\n");
295 rx_len = RX_FIFO_SIZE-1;
299 /* Passed in buffer wasn't big enough. Should never happen. */
300 dev_err(printdev(devrec), "Buffer not big enough. Performing short read\n");
304 /* Set up the commands to read the data. */
305 cmd = MRF24J40_READLONG(REG_RX_FIFO+1);
306 addr[0] = cmd >> 8 & 0xff;
307 addr[1] = cmd & 0xff;
308 data_xfer.len = rx_len;
310 spi_message_init(&msg);
311 spi_message_add_tail(&addr_xfer, &msg);
312 spi_message_add_tail(&data_xfer, &msg);
313 spi_message_add_tail(&status_xfer, &msg);
315 ret = spi_sync(devrec->spi, &msg);
317 dev_err(printdev(devrec), "SPI RX Buffer Read Failed.\n");
325 print_hex_dump(KERN_DEBUG, "mrf24j40 rx: ",
326 DUMP_PREFIX_OFFSET, 16, 1, data, *len, 0);
327 pr_debug("mrf24j40 rx: lqi: %02hhx rssi: %02hhx\n",
328 lqi_rssi[0], lqi_rssi[1]);
335 static int mrf24j40_tx(struct ieee802154_hw *hw, struct sk_buff *skb)
337 struct mrf24j40 *devrec = hw->priv;
341 dev_dbg(printdev(devrec), "tx packet of %d bytes\n", skb->len);
343 ret = write_tx_buf(devrec, 0x000, skb->data, skb->len);
347 reinit_completion(&devrec->tx_complete);
349 /* Set TXNTRIG bit of TXNCON to send packet */
350 ret = read_short_reg(devrec, REG_TXNCON, &val);
354 /* Set TXNACKREQ if the ACK bit is set in the packet. */
355 if (skb->data[0] & IEEE802154_FC_ACK_REQ)
357 write_short_reg(devrec, REG_TXNCON, val);
359 /* Wait for the device to send the TX complete interrupt. */
360 ret = wait_for_completion_interruptible_timeout(
361 &devrec->tx_complete,
363 if (ret == -ERESTARTSYS)
366 dev_warn(printdev(devrec), "Timeout waiting for TX interrupt\n");
371 /* Check for send error from the device. */
372 ret = read_short_reg(devrec, REG_TXSTAT, &val);
376 dev_dbg(printdev(devrec), "Error Sending. Retry count exceeded\n");
377 ret = -ECOMM; /* TODO: Better error code ? */
379 dev_dbg(printdev(devrec), "Packet Sent\n");
386 static int mrf24j40_ed(struct ieee802154_hw *hw, u8 *level)
389 pr_warn("mrf24j40: ed not implemented\n");
394 static int mrf24j40_start(struct ieee802154_hw *hw)
396 struct mrf24j40 *devrec = hw->priv;
400 dev_dbg(printdev(devrec), "start\n");
402 ret = read_short_reg(devrec, REG_INTCON, &val);
405 val &= ~(0x1|0x8); /* Clear TXNIE and RXIE. Enable interrupts */
406 write_short_reg(devrec, REG_INTCON, val);
411 static void mrf24j40_stop(struct ieee802154_hw *hw)
413 struct mrf24j40 *devrec = hw->priv;
417 dev_dbg(printdev(devrec), "stop\n");
419 ret = read_short_reg(devrec, REG_INTCON, &val);
422 val |= 0x1|0x8; /* Set TXNIE and RXIE. Disable Interrupts */
423 write_short_reg(devrec, REG_INTCON, val);
426 static int mrf24j40_set_channel(struct ieee802154_hw *hw, u8 page, u8 channel)
428 struct mrf24j40 *devrec = hw->priv;
432 dev_dbg(printdev(devrec), "Set Channel %d\n", channel);
435 WARN_ON(channel < MRF24J40_CHAN_MIN);
436 WARN_ON(channel > MRF24J40_CHAN_MAX);
438 /* Set Channel TODO */
439 val = (channel-11) << 4 | 0x03;
440 write_long_reg(devrec, REG_RFCON0, val);
443 ret = read_short_reg(devrec, REG_RFCTL, &val);
447 write_short_reg(devrec, REG_RFCTL, val);
449 write_short_reg(devrec, REG_RFCTL, val);
451 udelay(SET_CHANNEL_DELAY_US); /* per datasheet */
456 static int mrf24j40_filter(struct ieee802154_hw *hw,
457 struct ieee802154_hw_addr_filt *filt,
458 unsigned long changed)
460 struct mrf24j40 *devrec = hw->priv;
462 dev_dbg(printdev(devrec), "filter\n");
464 if (changed & IEEE802154_AFILT_SADDR_CHANGED) {
468 addrh = le16_to_cpu(filt->short_addr) >> 8 & 0xff;
469 addrl = le16_to_cpu(filt->short_addr) & 0xff;
471 write_short_reg(devrec, REG_SADRH, addrh);
472 write_short_reg(devrec, REG_SADRL, addrl);
473 dev_dbg(printdev(devrec),
474 "Set short addr to %04hx\n", filt->short_addr);
477 if (changed & IEEE802154_AFILT_IEEEADDR_CHANGED) {
481 memcpy(addr, &filt->ieee_addr, 8);
482 for (i = 0; i < 8; i++)
483 write_short_reg(devrec, REG_EADR0 + i, addr[i]);
486 pr_debug("Set long addr to: ");
487 for (i = 0; i < 8; i++)
488 pr_debug("%02hhx ", addr[7 - i]);
493 if (changed & IEEE802154_AFILT_PANID_CHANGED) {
497 panidh = le16_to_cpu(filt->pan_id) >> 8 & 0xff;
498 panidl = le16_to_cpu(filt->pan_id) & 0xff;
499 write_short_reg(devrec, REG_PANIDH, panidh);
500 write_short_reg(devrec, REG_PANIDL, panidl);
502 dev_dbg(printdev(devrec), "Set PANID to %04hx\n", filt->pan_id);
505 if (changed & IEEE802154_AFILT_PANC_CHANGED) {
506 /* Pan Coordinator */
510 ret = read_short_reg(devrec, REG_RXMCR, &val);
517 write_short_reg(devrec, REG_RXMCR, val);
519 /* REG_SLOTTED is maintained as default (unslotted/CSMA-CA).
520 * REG_ORDER is maintained as default (no beacon/superframe).
523 dev_dbg(printdev(devrec), "Set Pan Coord to %s\n",
524 filt->pan_coord ? "on" : "off");
530 static int mrf24j40_handle_rx(struct mrf24j40 *devrec)
532 u8 len = RX_FIFO_SIZE;
539 /* Turn off reception of packets off the air. This prevents the
540 * device from overwriting the buffer while we're reading it. */
541 ret = read_short_reg(devrec, REG_BBREG1, &val);
544 val |= 4; /* SET RXDECINV */
545 write_short_reg(devrec, REG_BBREG1, val);
547 skb = dev_alloc_skb(len);
553 ret = mrf24j40_read_rx_buf(devrec, skb_put(skb, len), &len, &lqi);
555 dev_err(printdev(devrec), "Failure reading RX FIFO\n");
561 /* Cut off the checksum */
562 skb_trim(skb, len-2);
564 /* TODO: Other drivers call ieee20154_rx_irqsafe() here (eg: cc2040,
565 * also from a workqueue). I think irqsafe is not necessary here.
566 * Can someone confirm? */
567 ieee802154_rx_irqsafe(devrec->hw, skb, lqi);
569 dev_dbg(printdev(devrec), "RX Handled\n");
572 /* Turn back on reception of packets off the air. */
573 ret2 = read_short_reg(devrec, REG_BBREG1, &val);
576 val &= ~0x4; /* Clear RXDECINV */
577 write_short_reg(devrec, REG_BBREG1, val);
582 static const struct ieee802154_ops mrf24j40_ops = {
583 .owner = THIS_MODULE,
584 .xmit_sync = mrf24j40_tx,
586 .start = mrf24j40_start,
587 .stop = mrf24j40_stop,
588 .set_channel = mrf24j40_set_channel,
589 .set_hw_addr_filt = mrf24j40_filter,
592 static irqreturn_t mrf24j40_isr(int irq, void *data)
594 struct mrf24j40 *devrec = data;
598 /* Read the interrupt status */
599 ret = read_short_reg(devrec, REG_INTSTAT, &intstat);
603 /* Check for TX complete */
605 complete(&devrec->tx_complete);
609 mrf24j40_handle_rx(devrec);
615 static int mrf24j40_hw_init(struct mrf24j40 *devrec)
620 /* Initialize the device.
621 From datasheet section 3.2: Initialization. */
622 ret = write_short_reg(devrec, REG_SOFTRST, 0x07);
626 ret = write_short_reg(devrec, REG_PACON2, 0x98);
630 ret = write_short_reg(devrec, REG_TXSTBL, 0x95);
634 ret = write_long_reg(devrec, REG_RFCON0, 0x03);
638 ret = write_long_reg(devrec, REG_RFCON1, 0x01);
642 ret = write_long_reg(devrec, REG_RFCON2, 0x80);
646 ret = write_long_reg(devrec, REG_RFCON6, 0x90);
650 ret = write_long_reg(devrec, REG_RFCON7, 0x80);
654 ret = write_long_reg(devrec, REG_RFCON8, 0x10);
658 ret = write_long_reg(devrec, REG_SLPCON1, 0x21);
662 ret = write_short_reg(devrec, REG_BBREG2, 0x80);
666 ret = write_short_reg(devrec, REG_CCAEDTH, 0x60);
670 ret = write_short_reg(devrec, REG_BBREG6, 0x40);
674 ret = write_short_reg(devrec, REG_RFCTL, 0x04);
678 ret = write_short_reg(devrec, REG_RFCTL, 0x0);
684 /* Set RX Mode. RXMCR<1:0>: 0x0 normal, 0x1 promisc, 0x2 error */
685 ret = read_short_reg(devrec, REG_RXMCR, &val);
689 val &= ~0x3; /* Clear RX mode (normal) */
691 ret = write_short_reg(devrec, REG_RXMCR, val);
695 if (spi_get_device_id(devrec->spi)->driver_data == MRF24J40MC) {
696 /* Enable external amplifier.
697 * From MRF24J40MC datasheet section 1.3: Operation.
699 read_long_reg(devrec, REG_TESTMODE, &val);
700 val |= 0x7; /* Configure GPIO 0-2 to control amplifier */
701 write_long_reg(devrec, REG_TESTMODE, val);
703 read_short_reg(devrec, REG_TRISGPIO, &val);
704 val |= 0x8; /* Set GPIO3 as output. */
705 write_short_reg(devrec, REG_TRISGPIO, val);
707 read_short_reg(devrec, REG_GPIO, &val);
708 val |= 0x8; /* Set GPIO3 HIGH to enable U5 voltage regulator */
709 write_short_reg(devrec, REG_GPIO, val);
711 /* Reduce TX pwr to meet FCC requirements.
712 * From MRF24J40MC datasheet section 3.1.1
714 write_long_reg(devrec, REG_RFCON3, 0x28);
723 static int mrf24j40_probe(struct spi_device *spi)
726 struct ieee802154_hw *hw;
727 struct mrf24j40 *devrec;
729 dev_info(&spi->dev, "probe(). IRQ: %d\n", spi->irq);
731 /* Register with the 802154 subsystem */
733 hw = ieee802154_alloc_hw(sizeof(*devrec), &mrf24j40_ops);
739 spi_set_drvdata(spi, devrec);
741 devrec->hw->parent = &spi->dev;
742 devrec->hw->phy->supported.channels[0] = CHANNEL_MASK;
743 devrec->hw->flags = IEEE802154_HW_OMIT_CKSUM | IEEE802154_HW_AFILT;
745 devrec->buf = devm_kzalloc(&spi->dev, 3, GFP_KERNEL);
747 goto err_register_device;
749 spi->mode = SPI_MODE_0; /* TODO: Is this appropriate for right here? */
750 if (spi->max_speed_hz > MAX_SPI_SPEED_HZ)
751 spi->max_speed_hz = MAX_SPI_SPEED_HZ;
753 mutex_init(&devrec->buffer_mutex);
754 init_completion(&devrec->tx_complete);
756 dev_dbg(printdev(devrec), "registered mrf24j40\n");
757 ret = ieee802154_register_hw(devrec->hw);
759 goto err_register_device;
761 ret = mrf24j40_hw_init(devrec);
765 ret = devm_request_threaded_irq(&spi->dev,
769 IRQF_TRIGGER_LOW|IRQF_ONESHOT,
774 dev_err(printdev(devrec), "Unable to get IRQ");
782 ieee802154_unregister_hw(devrec->hw);
784 ieee802154_free_hw(devrec->hw);
789 static int mrf24j40_remove(struct spi_device *spi)
791 struct mrf24j40 *devrec = spi_get_drvdata(spi);
793 dev_dbg(printdev(devrec), "remove\n");
795 ieee802154_unregister_hw(devrec->hw);
796 ieee802154_free_hw(devrec->hw);
797 /* TODO: Will ieee802154_free_device() wait until ->xmit() is
803 static const struct spi_device_id mrf24j40_ids[] = {
804 { "mrf24j40", MRF24J40 },
805 { "mrf24j40ma", MRF24J40MA },
806 { "mrf24j40mc", MRF24J40MC },
809 MODULE_DEVICE_TABLE(spi, mrf24j40_ids);
811 static struct spi_driver mrf24j40_driver = {
814 .owner = THIS_MODULE,
816 .id_table = mrf24j40_ids,
817 .probe = mrf24j40_probe,
818 .remove = mrf24j40_remove,
821 module_spi_driver(mrf24j40_driver);
823 MODULE_LICENSE("GPL");
824 MODULE_AUTHOR("Alan Ott");
825 MODULE_DESCRIPTION("MRF24J40 SPI 802.15.4 Controller Driver");