1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Driver for TI CC2520 802.15.4 Wireless-PAN Networking controller
3 *
4 * Copyright (C) 2014 Varka Bhadram <varkab@cdac.in>
5 * Md.Jamal Mohiuddin <mjmohiuddin@cdac.in>
6 * P Sowjanya <sowjanyap@cdac.in>
7 */
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/gpio.h>
11 #include <linux/delay.h>
12 #include <linux/spi/spi.h>
13 #include <linux/spi/cc2520.h>
14 #include <linux/workqueue.h>
15 #include <linux/interrupt.h>
16 #include <linux/skbuff.h>
17 #include <linux/of_gpio.h>
18 #include <linux/ieee802154.h>
19 #include <linux/crc-ccitt.h>
20 #include <asm/unaligned.h>
21
22 #include <net/mac802154.h>
23 #include <net/cfg802154.h>
24
25 #define SPI_COMMAND_BUFFER 3
26 #define HIGH 1
27 #define LOW 0
28 #define STATE_IDLE 0
29 #define RSSI_VALID 0
30 #define RSSI_OFFSET 78
31
32 #define CC2520_RAM_SIZE 640
33 #define CC2520_FIFO_SIZE 128
34
35 #define CC2520RAM_TXFIFO 0x100
36 #define CC2520RAM_RXFIFO 0x180
37 #define CC2520RAM_IEEEADDR 0x3EA
38 #define CC2520RAM_PANID 0x3F2
39 #define CC2520RAM_SHORTADDR 0x3F4
40
41 #define CC2520_FREG_MASK 0x3F
42
43 /* status byte values */
44 #define CC2520_STATUS_XOSC32M_STABLE BIT(7)
45 #define CC2520_STATUS_RSSI_VALID BIT(6)
46 #define CC2520_STATUS_TX_UNDERFLOW BIT(3)
47
48 /* IEEE-802.15.4 defined constants (2.4 GHz logical channels) */
49 #define CC2520_MINCHANNEL 11
50 #define CC2520_MAXCHANNEL 26
51 #define CC2520_CHANNEL_SPACING 5
52
53 /* command strobes */
54 #define CC2520_CMD_SNOP 0x00
55 #define CC2520_CMD_IBUFLD 0x02
56 #define CC2520_CMD_SIBUFEX 0x03
57 #define CC2520_CMD_SSAMPLECCA 0x04
58 #define CC2520_CMD_SRES 0x0f
59 #define CC2520_CMD_MEMORY_MASK 0x0f
60 #define CC2520_CMD_MEMORY_READ 0x10
61 #define CC2520_CMD_MEMORY_WRITE 0x20
62 #define CC2520_CMD_RXBUF 0x30
63 #define CC2520_CMD_RXBUFCP 0x38
64 #define CC2520_CMD_RXBUFMOV 0x32
65 #define CC2520_CMD_TXBUF 0x3A
66 #define CC2520_CMD_TXBUFCP 0x3E
67 #define CC2520_CMD_RANDOM 0x3C
68 #define CC2520_CMD_SXOSCON 0x40
69 #define CC2520_CMD_STXCAL 0x41
70 #define CC2520_CMD_SRXON 0x42
71 #define CC2520_CMD_STXON 0x43
72 #define CC2520_CMD_STXONCCA 0x44
73 #define CC2520_CMD_SRFOFF 0x45
74 #define CC2520_CMD_SXOSCOFF 0x46
75 #define CC2520_CMD_SFLUSHRX 0x47
76 #define CC2520_CMD_SFLUSHTX 0x48
77 #define CC2520_CMD_SACK 0x49
78 #define CC2520_CMD_SACKPEND 0x4A
79 #define CC2520_CMD_SNACK 0x4B
80 #define CC2520_CMD_SRXMASKBITSET 0x4C
81 #define CC2520_CMD_SRXMASKBITCLR 0x4D
82 #define CC2520_CMD_RXMASKAND 0x4E
83 #define CC2520_CMD_RXMASKOR 0x4F
84 #define CC2520_CMD_MEMCP 0x50
85 #define CC2520_CMD_MEMCPR 0x52
86 #define CC2520_CMD_MEMXCP 0x54
87 #define CC2520_CMD_MEMXWR 0x56
88 #define CC2520_CMD_BCLR 0x58
89 #define CC2520_CMD_BSET 0x59
90 #define CC2520_CMD_CTR_UCTR 0x60
91 #define CC2520_CMD_CBCMAC 0x64
92 #define CC2520_CMD_UCBCMAC 0x66
93 #define CC2520_CMD_CCM 0x68
94 #define CC2520_CMD_UCCM 0x6A
95 #define CC2520_CMD_ECB 0x70
96 #define CC2520_CMD_ECBO 0x72
97 #define CC2520_CMD_ECBX 0x74
98 #define CC2520_CMD_INC 0x78
99 #define CC2520_CMD_ABORT 0x7F
100 #define CC2520_CMD_REGISTER_READ 0x80
101 #define CC2520_CMD_REGISTER_WRITE 0xC0
102
103 /* status registers */
104 #define CC2520_CHIPID 0x40
105 #define CC2520_VERSION 0x42
106 #define CC2520_EXTCLOCK 0x44
107 #define CC2520_MDMCTRL0 0x46
108 #define CC2520_MDMCTRL1 0x47
109 #define CC2520_FREQEST 0x48
110 #define CC2520_RXCTRL 0x4A
111 #define CC2520_FSCTRL 0x4C
112 #define CC2520_FSCAL0 0x4E
113 #define CC2520_FSCAL1 0x4F
114 #define CC2520_FSCAL2 0x50
115 #define CC2520_FSCAL3 0x51
116 #define CC2520_AGCCTRL0 0x52
117 #define CC2520_AGCCTRL1 0x53
118 #define CC2520_AGCCTRL2 0x54
119 #define CC2520_AGCCTRL3 0x55
120 #define CC2520_ADCTEST0 0x56
121 #define CC2520_ADCTEST1 0x57
122 #define CC2520_ADCTEST2 0x58
123 #define CC2520_MDMTEST0 0x5A
124 #define CC2520_MDMTEST1 0x5B
125 #define CC2520_DACTEST0 0x5C
126 #define CC2520_DACTEST1 0x5D
127 #define CC2520_ATEST 0x5E
128 #define CC2520_DACTEST2 0x5F
129 #define CC2520_PTEST0 0x60
130 #define CC2520_PTEST1 0x61
131 #define CC2520_RESERVED 0x62
132 #define CC2520_DPUBIST 0x7A
133 #define CC2520_ACTBIST 0x7C
134 #define CC2520_RAMBIST 0x7E
135
136 /* frame registers */
137 #define CC2520_FRMFILT0 0x00
138 #define CC2520_FRMFILT1 0x01
139 #define CC2520_SRCMATCH 0x02
140 #define CC2520_SRCSHORTEN0 0x04
141 #define CC2520_SRCSHORTEN1 0x05
142 #define CC2520_SRCSHORTEN2 0x06
143 #define CC2520_SRCEXTEN0 0x08
144 #define CC2520_SRCEXTEN1 0x09
145 #define CC2520_SRCEXTEN2 0x0A
146 #define CC2520_FRMCTRL0 0x0C
147 #define CC2520_FRMCTRL1 0x0D
148 #define CC2520_RXENABLE0 0x0E
149 #define CC2520_RXENABLE1 0x0F
150 #define CC2520_EXCFLAG0 0x10
151 #define CC2520_EXCFLAG1 0x11
152 #define CC2520_EXCFLAG2 0x12
153 #define CC2520_EXCMASKA0 0x14
154 #define CC2520_EXCMASKA1 0x15
155 #define CC2520_EXCMASKA2 0x16
156 #define CC2520_EXCMASKB0 0x18
157 #define CC2520_EXCMASKB1 0x19
158 #define CC2520_EXCMASKB2 0x1A
159 #define CC2520_EXCBINDX0 0x1C
160 #define CC2520_EXCBINDX1 0x1D
161 #define CC2520_EXCBINDY0 0x1E
162 #define CC2520_EXCBINDY1 0x1F
163 #define CC2520_GPIOCTRL0 0x20
164 #define CC2520_GPIOCTRL1 0x21
165 #define CC2520_GPIOCTRL2 0x22
166 #define CC2520_GPIOCTRL3 0x23
167 #define CC2520_GPIOCTRL4 0x24
168 #define CC2520_GPIOCTRL5 0x25
169 #define CC2520_GPIOPOLARITY 0x26
170 #define CC2520_GPIOCTRL 0x28
171 #define CC2520_DPUCON 0x2A
172 #define CC2520_DPUSTAT 0x2C
173 #define CC2520_FREQCTRL 0x2E
174 #define CC2520_FREQTUNE 0x2F
175 #define CC2520_TXPOWER 0x30
176 #define CC2520_TXCTRL 0x31
177 #define CC2520_FSMSTAT0 0x32
178 #define CC2520_FSMSTAT1 0x33
179 #define CC2520_FIFOPCTRL 0x34
180 #define CC2520_FSMCTRL 0x35
181 #define CC2520_CCACTRL0 0x36
182 #define CC2520_CCACTRL1 0x37
183 #define CC2520_RSSI 0x38
184 #define CC2520_RSSISTAT 0x39
185 #define CC2520_RXFIRST 0x3C
186 #define CC2520_RXFIFOCNT 0x3E
187 #define CC2520_TXFIFOCNT 0x3F
188
189 /* CC2520_FRMFILT0 */
190 #define FRMFILT0_FRAME_FILTER_EN BIT(0)
191 #define FRMFILT0_PAN_COORDINATOR BIT(1)
192
193 /* CC2520_FRMCTRL0 */
194 #define FRMCTRL0_AUTOACK BIT(5)
195 #define FRMCTRL0_AUTOCRC BIT(6)
196
197 /* CC2520_FRMCTRL1 */
198 #define FRMCTRL1_SET_RXENMASK_ON_TX BIT(0)
199 #define FRMCTRL1_IGNORE_TX_UNDERF BIT(1)
200
201 /* Driver private information */
202 struct cc2520_private {
203 struct spi_device *spi; /* SPI device structure */
204 struct ieee802154_hw *hw; /* IEEE-802.15.4 device */
205 u8 *buf; /* SPI TX/Rx data buffer */
206 struct mutex buffer_mutex; /* SPI buffer mutex */
207 bool is_tx; /* Flag for sync b/w Tx and Rx */
208 bool amplified; /* Flag for CC2591 */
209 int fifo_pin; /* FIFO GPIO pin number */
210 struct work_struct fifop_irqwork;/* Workqueue for FIFOP */
211 spinlock_t lock; /* Lock for is_tx*/
212 struct completion tx_complete; /* Work completion for Tx */
213 bool promiscuous; /* Flag for promiscuous mode */
214 };
215
216 /* Generic Functions */
217 static int
cc2520_cmd_strobe(struct cc2520_private * priv,u8 cmd)218 cc2520_cmd_strobe(struct cc2520_private *priv, u8 cmd)
219 {
220 int ret;
221 struct spi_message msg;
222 struct spi_transfer xfer = {
223 .len = 0,
224 .tx_buf = priv->buf,
225 .rx_buf = priv->buf,
226 };
227
228 spi_message_init(&msg);
229 spi_message_add_tail(&xfer, &msg);
230
231 mutex_lock(&priv->buffer_mutex);
232 priv->buf[xfer.len++] = cmd;
233 dev_vdbg(&priv->spi->dev,
234 "command strobe buf[0] = %02x\n",
235 priv->buf[0]);
236
237 ret = spi_sync(priv->spi, &msg);
238 dev_vdbg(&priv->spi->dev,
239 "buf[0] = %02x\n", priv->buf[0]);
240 mutex_unlock(&priv->buffer_mutex);
241
242 return ret;
243 }
244
245 static int
cc2520_get_status(struct cc2520_private * priv,u8 * status)246 cc2520_get_status(struct cc2520_private *priv, u8 *status)
247 {
248 int ret;
249 struct spi_message msg;
250 struct spi_transfer xfer = {
251 .len = 0,
252 .tx_buf = priv->buf,
253 .rx_buf = priv->buf,
254 };
255
256 spi_message_init(&msg);
257 spi_message_add_tail(&xfer, &msg);
258
259 mutex_lock(&priv->buffer_mutex);
260 priv->buf[xfer.len++] = CC2520_CMD_SNOP;
261 dev_vdbg(&priv->spi->dev,
262 "get status command buf[0] = %02x\n", priv->buf[0]);
263
264 ret = spi_sync(priv->spi, &msg);
265 if (!ret)
266 *status = priv->buf[0];
267 dev_vdbg(&priv->spi->dev,
268 "buf[0] = %02x\n", priv->buf[0]);
269 mutex_unlock(&priv->buffer_mutex);
270
271 return ret;
272 }
273
274 static int
cc2520_write_register(struct cc2520_private * priv,u8 reg,u8 value)275 cc2520_write_register(struct cc2520_private *priv, u8 reg, u8 value)
276 {
277 int status;
278 struct spi_message msg;
279 struct spi_transfer xfer = {
280 .len = 0,
281 .tx_buf = priv->buf,
282 .rx_buf = priv->buf,
283 };
284
285 spi_message_init(&msg);
286 spi_message_add_tail(&xfer, &msg);
287
288 mutex_lock(&priv->buffer_mutex);
289
290 if (reg <= CC2520_FREG_MASK) {
291 priv->buf[xfer.len++] = CC2520_CMD_REGISTER_WRITE | reg;
292 priv->buf[xfer.len++] = value;
293 } else {
294 priv->buf[xfer.len++] = CC2520_CMD_MEMORY_WRITE;
295 priv->buf[xfer.len++] = reg;
296 priv->buf[xfer.len++] = value;
297 }
298 status = spi_sync(priv->spi, &msg);
299 if (msg.status)
300 status = msg.status;
301
302 mutex_unlock(&priv->buffer_mutex);
303
304 return status;
305 }
306
307 static int
cc2520_write_ram(struct cc2520_private * priv,u16 reg,u8 len,u8 * data)308 cc2520_write_ram(struct cc2520_private *priv, u16 reg, u8 len, u8 *data)
309 {
310 int status;
311 struct spi_message msg;
312 struct spi_transfer xfer_head = {
313 .len = 0,
314 .tx_buf = priv->buf,
315 .rx_buf = priv->buf,
316 };
317
318 struct spi_transfer xfer_buf = {
319 .len = len,
320 .tx_buf = data,
321 };
322
323 mutex_lock(&priv->buffer_mutex);
324 priv->buf[xfer_head.len++] = (CC2520_CMD_MEMORY_WRITE |
325 ((reg >> 8) & 0xff));
326 priv->buf[xfer_head.len++] = reg & 0xff;
327
328 spi_message_init(&msg);
329 spi_message_add_tail(&xfer_head, &msg);
330 spi_message_add_tail(&xfer_buf, &msg);
331
332 status = spi_sync(priv->spi, &msg);
333 dev_dbg(&priv->spi->dev, "spi status = %d\n", status);
334 if (msg.status)
335 status = msg.status;
336
337 mutex_unlock(&priv->buffer_mutex);
338 return status;
339 }
340
341 static int
cc2520_read_register(struct cc2520_private * priv,u8 reg,u8 * data)342 cc2520_read_register(struct cc2520_private *priv, u8 reg, u8 *data)
343 {
344 int status;
345 struct spi_message msg;
346 struct spi_transfer xfer1 = {
347 .len = 0,
348 .tx_buf = priv->buf,
349 .rx_buf = priv->buf,
350 };
351
352 struct spi_transfer xfer2 = {
353 .len = 1,
354 .rx_buf = data,
355 };
356
357 spi_message_init(&msg);
358 spi_message_add_tail(&xfer1, &msg);
359 spi_message_add_tail(&xfer2, &msg);
360
361 mutex_lock(&priv->buffer_mutex);
362 priv->buf[xfer1.len++] = CC2520_CMD_MEMORY_READ;
363 priv->buf[xfer1.len++] = reg;
364
365 status = spi_sync(priv->spi, &msg);
366 dev_dbg(&priv->spi->dev,
367 "spi status = %d\n", status);
368 if (msg.status)
369 status = msg.status;
370
371 mutex_unlock(&priv->buffer_mutex);
372
373 return status;
374 }
375
376 static int
cc2520_write_txfifo(struct cc2520_private * priv,u8 pkt_len,u8 * data,u8 len)377 cc2520_write_txfifo(struct cc2520_private *priv, u8 pkt_len, u8 *data, u8 len)
378 {
379 int status;
380
381 /* length byte must include FCS even
382 * if it is calculated in the hardware
383 */
384 int len_byte = pkt_len;
385
386 struct spi_message msg;
387
388 struct spi_transfer xfer_head = {
389 .len = 0,
390 .tx_buf = priv->buf,
391 .rx_buf = priv->buf,
392 };
393 struct spi_transfer xfer_len = {
394 .len = 1,
395 .tx_buf = &len_byte,
396 };
397 struct spi_transfer xfer_buf = {
398 .len = len,
399 .tx_buf = data,
400 };
401
402 spi_message_init(&msg);
403 spi_message_add_tail(&xfer_head, &msg);
404 spi_message_add_tail(&xfer_len, &msg);
405 spi_message_add_tail(&xfer_buf, &msg);
406
407 mutex_lock(&priv->buffer_mutex);
408 priv->buf[xfer_head.len++] = CC2520_CMD_TXBUF;
409 dev_vdbg(&priv->spi->dev,
410 "TX_FIFO cmd buf[0] = %02x\n", priv->buf[0]);
411
412 status = spi_sync(priv->spi, &msg);
413 dev_vdbg(&priv->spi->dev, "status = %d\n", status);
414 if (msg.status)
415 status = msg.status;
416 dev_vdbg(&priv->spi->dev, "status = %d\n", status);
417 dev_vdbg(&priv->spi->dev, "buf[0] = %02x\n", priv->buf[0]);
418 mutex_unlock(&priv->buffer_mutex);
419
420 return status;
421 }
422
423 static int
cc2520_read_rxfifo(struct cc2520_private * priv,u8 * data,u8 len)424 cc2520_read_rxfifo(struct cc2520_private *priv, u8 *data, u8 len)
425 {
426 int status;
427 struct spi_message msg;
428
429 struct spi_transfer xfer_head = {
430 .len = 0,
431 .tx_buf = priv->buf,
432 .rx_buf = priv->buf,
433 };
434 struct spi_transfer xfer_buf = {
435 .len = len,
436 .rx_buf = data,
437 };
438
439 spi_message_init(&msg);
440 spi_message_add_tail(&xfer_head, &msg);
441 spi_message_add_tail(&xfer_buf, &msg);
442
443 mutex_lock(&priv->buffer_mutex);
444 priv->buf[xfer_head.len++] = CC2520_CMD_RXBUF;
445
446 dev_vdbg(&priv->spi->dev, "read rxfifo buf[0] = %02x\n", priv->buf[0]);
447 dev_vdbg(&priv->spi->dev, "buf[1] = %02x\n", priv->buf[1]);
448
449 status = spi_sync(priv->spi, &msg);
450 dev_vdbg(&priv->spi->dev, "status = %d\n", status);
451 if (msg.status)
452 status = msg.status;
453 dev_vdbg(&priv->spi->dev, "status = %d\n", status);
454 dev_vdbg(&priv->spi->dev,
455 "return status buf[0] = %02x\n", priv->buf[0]);
456 dev_vdbg(&priv->spi->dev, "length buf[1] = %02x\n", priv->buf[1]);
457
458 mutex_unlock(&priv->buffer_mutex);
459
460 return status;
461 }
462
cc2520_start(struct ieee802154_hw * hw)463 static int cc2520_start(struct ieee802154_hw *hw)
464 {
465 return cc2520_cmd_strobe(hw->priv, CC2520_CMD_SRXON);
466 }
467
cc2520_stop(struct ieee802154_hw * hw)468 static void cc2520_stop(struct ieee802154_hw *hw)
469 {
470 cc2520_cmd_strobe(hw->priv, CC2520_CMD_SRFOFF);
471 }
472
473 static int
cc2520_tx(struct ieee802154_hw * hw,struct sk_buff * skb)474 cc2520_tx(struct ieee802154_hw *hw, struct sk_buff *skb)
475 {
476 struct cc2520_private *priv = hw->priv;
477 unsigned long flags;
478 int rc;
479 u8 status = 0;
480 u8 pkt_len;
481
482 /* In promiscuous mode we disable AUTOCRC so we can get the raw CRC
483 * values on RX. This means we need to manually add the CRC on TX.
484 */
485 if (priv->promiscuous) {
486 u16 crc = crc_ccitt(0, skb->data, skb->len);
487
488 put_unaligned_le16(crc, skb_put(skb, 2));
489 pkt_len = skb->len;
490 } else {
491 pkt_len = skb->len + 2;
492 }
493
494 rc = cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHTX);
495 if (rc)
496 goto err_tx;
497
498 rc = cc2520_write_txfifo(priv, pkt_len, skb->data, skb->len);
499 if (rc)
500 goto err_tx;
501
502 rc = cc2520_get_status(priv, &status);
503 if (rc)
504 goto err_tx;
505
506 if (status & CC2520_STATUS_TX_UNDERFLOW) {
507 dev_err(&priv->spi->dev, "cc2520 tx underflow exception\n");
508 goto err_tx;
509 }
510
511 spin_lock_irqsave(&priv->lock, flags);
512 WARN_ON(priv->is_tx);
513 priv->is_tx = 1;
514 spin_unlock_irqrestore(&priv->lock, flags);
515
516 rc = cc2520_cmd_strobe(priv, CC2520_CMD_STXONCCA);
517 if (rc)
518 goto err;
519
520 rc = wait_for_completion_interruptible(&priv->tx_complete);
521 if (rc < 0)
522 goto err;
523
524 cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHTX);
525 cc2520_cmd_strobe(priv, CC2520_CMD_SRXON);
526
527 return rc;
528 err:
529 spin_lock_irqsave(&priv->lock, flags);
530 priv->is_tx = 0;
531 spin_unlock_irqrestore(&priv->lock, flags);
532 err_tx:
533 return rc;
534 }
535
cc2520_rx(struct cc2520_private * priv)536 static int cc2520_rx(struct cc2520_private *priv)
537 {
538 u8 len = 0, lqi = 0, bytes = 1;
539 struct sk_buff *skb;
540
541 /* Read single length byte from the radio. */
542 cc2520_read_rxfifo(priv, &len, bytes);
543
544 if (!ieee802154_is_valid_psdu_len(len)) {
545 /* Corrupted frame received, clear frame buffer by
546 * reading entire buffer.
547 */
548 dev_dbg(&priv->spi->dev, "corrupted frame received\n");
549 len = IEEE802154_MTU;
550 }
551
552 skb = dev_alloc_skb(len);
553 if (!skb)
554 return -ENOMEM;
555
556 if (cc2520_read_rxfifo(priv, skb_put(skb, len), len)) {
557 dev_dbg(&priv->spi->dev, "frame reception failed\n");
558 kfree_skb(skb);
559 return -EINVAL;
560 }
561
562 /* In promiscuous mode, we configure the radio to include the
563 * CRC (AUTOCRC==0) and we pass on the packet unconditionally. If not
564 * in promiscuous mode, we check the CRC here, but leave the
565 * RSSI/LQI/CRC_OK bytes as they will get removed in the mac layer.
566 */
567 if (!priv->promiscuous) {
568 bool crc_ok;
569
570 /* Check if the CRC is valid. With AUTOCRC set, the most
571 * significant bit of the last byte returned from the CC2520
572 * is CRC_OK flag. See section 20.3.4 of the datasheet.
573 */
574 crc_ok = skb->data[len - 1] & BIT(7);
575
576 /* If we failed CRC drop the packet in the driver layer. */
577 if (!crc_ok) {
578 dev_dbg(&priv->spi->dev, "CRC check failed\n");
579 kfree_skb(skb);
580 return -EINVAL;
581 }
582
583 /* To calculate LQI, the lower 7 bits of the last byte (the
584 * correlation value provided by the radio) must be scaled to
585 * the range 0-255. According to section 20.6, the correlation
586 * value ranges from 50-110. Ideally this would be calibrated
587 * per hardware design, but we use roughly the datasheet values
588 * to get close enough while avoiding floating point.
589 */
590 lqi = skb->data[len - 1] & 0x7f;
591 if (lqi < 50)
592 lqi = 50;
593 else if (lqi > 113)
594 lqi = 113;
595 lqi = (lqi - 50) * 4;
596 }
597
598 ieee802154_rx_irqsafe(priv->hw, skb, lqi);
599
600 dev_vdbg(&priv->spi->dev, "RXFIFO: %x %x\n", len, lqi);
601
602 return 0;
603 }
604
605 static int
cc2520_ed(struct ieee802154_hw * hw,u8 * level)606 cc2520_ed(struct ieee802154_hw *hw, u8 *level)
607 {
608 struct cc2520_private *priv = hw->priv;
609 u8 status = 0xff;
610 u8 rssi;
611 int ret;
612
613 ret = cc2520_read_register(priv, CC2520_RSSISTAT, &status);
614 if (ret)
615 return ret;
616
617 if (status != RSSI_VALID)
618 return -EINVAL;
619
620 ret = cc2520_read_register(priv, CC2520_RSSI, &rssi);
621 if (ret)
622 return ret;
623
624 /* level = RSSI(rssi) - OFFSET [dBm] : offset is 76dBm */
625 *level = rssi - RSSI_OFFSET;
626
627 return 0;
628 }
629
630 static int
cc2520_set_channel(struct ieee802154_hw * hw,u8 page,u8 channel)631 cc2520_set_channel(struct ieee802154_hw *hw, u8 page, u8 channel)
632 {
633 struct cc2520_private *priv = hw->priv;
634 int ret;
635
636 dev_dbg(&priv->spi->dev, "trying to set channel\n");
637
638 WARN_ON(page != 0);
639 WARN_ON(channel < CC2520_MINCHANNEL);
640 WARN_ON(channel > CC2520_MAXCHANNEL);
641
642 ret = cc2520_write_register(priv, CC2520_FREQCTRL,
643 11 + 5 * (channel - 11));
644
645 return ret;
646 }
647
648 static int
cc2520_filter(struct ieee802154_hw * hw,struct ieee802154_hw_addr_filt * filt,unsigned long changed)649 cc2520_filter(struct ieee802154_hw *hw,
650 struct ieee802154_hw_addr_filt *filt, unsigned long changed)
651 {
652 struct cc2520_private *priv = hw->priv;
653 int ret = 0;
654
655 if (changed & IEEE802154_AFILT_PANID_CHANGED) {
656 u16 panid = le16_to_cpu(filt->pan_id);
657
658 dev_vdbg(&priv->spi->dev, "%s called for pan id\n", __func__);
659 ret = cc2520_write_ram(priv, CC2520RAM_PANID,
660 sizeof(panid), (u8 *)&panid);
661 }
662
663 if (changed & IEEE802154_AFILT_IEEEADDR_CHANGED) {
664 dev_vdbg(&priv->spi->dev,
665 "%s called for IEEE addr\n", __func__);
666 ret = cc2520_write_ram(priv, CC2520RAM_IEEEADDR,
667 sizeof(filt->ieee_addr),
668 (u8 *)&filt->ieee_addr);
669 }
670
671 if (changed & IEEE802154_AFILT_SADDR_CHANGED) {
672 u16 addr = le16_to_cpu(filt->short_addr);
673
674 dev_vdbg(&priv->spi->dev, "%s called for saddr\n", __func__);
675 ret = cc2520_write_ram(priv, CC2520RAM_SHORTADDR,
676 sizeof(addr), (u8 *)&addr);
677 }
678
679 if (changed & IEEE802154_AFILT_PANC_CHANGED) {
680 u8 frmfilt0;
681
682 dev_vdbg(&priv->spi->dev,
683 "%s called for panc change\n", __func__);
684
685 cc2520_read_register(priv, CC2520_FRMFILT0, &frmfilt0);
686
687 if (filt->pan_coord)
688 frmfilt0 |= FRMFILT0_PAN_COORDINATOR;
689 else
690 frmfilt0 &= ~FRMFILT0_PAN_COORDINATOR;
691
692 ret = cc2520_write_register(priv, CC2520_FRMFILT0, frmfilt0);
693 }
694
695 return ret;
696 }
697
cc2520_set_tx_power(struct cc2520_private * priv,s32 mbm)698 static inline int cc2520_set_tx_power(struct cc2520_private *priv, s32 mbm)
699 {
700 u8 power;
701
702 switch (mbm) {
703 case 500:
704 power = 0xF7;
705 break;
706 case 300:
707 power = 0xF2;
708 break;
709 case 200:
710 power = 0xAB;
711 break;
712 case 100:
713 power = 0x13;
714 break;
715 case 0:
716 power = 0x32;
717 break;
718 case -200:
719 power = 0x81;
720 break;
721 case -400:
722 power = 0x88;
723 break;
724 case -700:
725 power = 0x2C;
726 break;
727 case -1800:
728 power = 0x03;
729 break;
730 default:
731 return -EINVAL;
732 }
733
734 return cc2520_write_register(priv, CC2520_TXPOWER, power);
735 }
736
cc2520_cc2591_set_tx_power(struct cc2520_private * priv,s32 mbm)737 static inline int cc2520_cc2591_set_tx_power(struct cc2520_private *priv,
738 s32 mbm)
739 {
740 u8 power;
741
742 switch (mbm) {
743 case 1700:
744 power = 0xF9;
745 break;
746 case 1600:
747 power = 0xF0;
748 break;
749 case 1400:
750 power = 0xA0;
751 break;
752 case 1100:
753 power = 0x2C;
754 break;
755 case -100:
756 power = 0x03;
757 break;
758 case -800:
759 power = 0x01;
760 break;
761 default:
762 return -EINVAL;
763 }
764
765 return cc2520_write_register(priv, CC2520_TXPOWER, power);
766 }
767
768 #define CC2520_MAX_TX_POWERS 0x8
769 static const s32 cc2520_powers[CC2520_MAX_TX_POWERS + 1] = {
770 500, 300, 200, 100, 0, -200, -400, -700, -1800,
771 };
772
773 #define CC2520_CC2591_MAX_TX_POWERS 0x5
774 static const s32 cc2520_cc2591_powers[CC2520_CC2591_MAX_TX_POWERS + 1] = {
775 1700, 1600, 1400, 1100, -100, -800,
776 };
777
778 static int
cc2520_set_txpower(struct ieee802154_hw * hw,s32 mbm)779 cc2520_set_txpower(struct ieee802154_hw *hw, s32 mbm)
780 {
781 struct cc2520_private *priv = hw->priv;
782
783 if (!priv->amplified)
784 return cc2520_set_tx_power(priv, mbm);
785
786 return cc2520_cc2591_set_tx_power(priv, mbm);
787 }
788
789 static int
cc2520_set_promiscuous_mode(struct ieee802154_hw * hw,bool on)790 cc2520_set_promiscuous_mode(struct ieee802154_hw *hw, bool on)
791 {
792 struct cc2520_private *priv = hw->priv;
793 u8 frmfilt0;
794
795 dev_dbg(&priv->spi->dev, "%s : mode %d\n", __func__, on);
796
797 priv->promiscuous = on;
798
799 cc2520_read_register(priv, CC2520_FRMFILT0, &frmfilt0);
800
801 if (on) {
802 /* Disable automatic ACK, automatic CRC, and frame filtering. */
803 cc2520_write_register(priv, CC2520_FRMCTRL0, 0);
804 frmfilt0 &= ~FRMFILT0_FRAME_FILTER_EN;
805 } else {
806 cc2520_write_register(priv, CC2520_FRMCTRL0, FRMCTRL0_AUTOACK |
807 FRMCTRL0_AUTOCRC);
808 frmfilt0 |= FRMFILT0_FRAME_FILTER_EN;
809 }
810 return cc2520_write_register(priv, CC2520_FRMFILT0, frmfilt0);
811 }
812
813 static const struct ieee802154_ops cc2520_ops = {
814 .owner = THIS_MODULE,
815 .start = cc2520_start,
816 .stop = cc2520_stop,
817 .xmit_sync = cc2520_tx,
818 .ed = cc2520_ed,
819 .set_channel = cc2520_set_channel,
820 .set_hw_addr_filt = cc2520_filter,
821 .set_txpower = cc2520_set_txpower,
822 .set_promiscuous_mode = cc2520_set_promiscuous_mode,
823 };
824
cc2520_register(struct cc2520_private * priv)825 static int cc2520_register(struct cc2520_private *priv)
826 {
827 int ret = -ENOMEM;
828
829 priv->hw = ieee802154_alloc_hw(sizeof(*priv), &cc2520_ops);
830 if (!priv->hw)
831 goto err_ret;
832
833 priv->hw->priv = priv;
834 priv->hw->parent = &priv->spi->dev;
835 priv->hw->extra_tx_headroom = 0;
836 ieee802154_random_extended_addr(&priv->hw->phy->perm_extended_addr);
837
838 /* We do support only 2.4 Ghz */
839 priv->hw->phy->supported.channels[0] = 0x7FFF800;
840 priv->hw->flags = IEEE802154_HW_TX_OMIT_CKSUM | IEEE802154_HW_AFILT |
841 IEEE802154_HW_PROMISCUOUS;
842
843 priv->hw->phy->flags = WPAN_PHY_FLAG_TXPOWER;
844
845 if (!priv->amplified) {
846 priv->hw->phy->supported.tx_powers = cc2520_powers;
847 priv->hw->phy->supported.tx_powers_size = ARRAY_SIZE(cc2520_powers);
848 priv->hw->phy->transmit_power = priv->hw->phy->supported.tx_powers[4];
849 } else {
850 priv->hw->phy->supported.tx_powers = cc2520_cc2591_powers;
851 priv->hw->phy->supported.tx_powers_size = ARRAY_SIZE(cc2520_cc2591_powers);
852 priv->hw->phy->transmit_power = priv->hw->phy->supported.tx_powers[0];
853 }
854
855 priv->hw->phy->current_channel = 11;
856
857 dev_vdbg(&priv->spi->dev, "registered cc2520\n");
858 ret = ieee802154_register_hw(priv->hw);
859 if (ret)
860 goto err_free_device;
861
862 return 0;
863
864 err_free_device:
865 ieee802154_free_hw(priv->hw);
866 err_ret:
867 return ret;
868 }
869
cc2520_fifop_irqwork(struct work_struct * work)870 static void cc2520_fifop_irqwork(struct work_struct *work)
871 {
872 struct cc2520_private *priv
873 = container_of(work, struct cc2520_private, fifop_irqwork);
874
875 dev_dbg(&priv->spi->dev, "fifop interrupt received\n");
876
877 if (gpio_get_value(priv->fifo_pin))
878 cc2520_rx(priv);
879 else
880 dev_dbg(&priv->spi->dev, "rxfifo overflow\n");
881
882 cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHRX);
883 cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHRX);
884 }
885
cc2520_fifop_isr(int irq,void * data)886 static irqreturn_t cc2520_fifop_isr(int irq, void *data)
887 {
888 struct cc2520_private *priv = data;
889
890 schedule_work(&priv->fifop_irqwork);
891
892 return IRQ_HANDLED;
893 }
894
cc2520_sfd_isr(int irq,void * data)895 static irqreturn_t cc2520_sfd_isr(int irq, void *data)
896 {
897 struct cc2520_private *priv = data;
898 unsigned long flags;
899
900 spin_lock_irqsave(&priv->lock, flags);
901 if (priv->is_tx) {
902 priv->is_tx = 0;
903 spin_unlock_irqrestore(&priv->lock, flags);
904 dev_dbg(&priv->spi->dev, "SFD for TX\n");
905 complete(&priv->tx_complete);
906 } else {
907 spin_unlock_irqrestore(&priv->lock, flags);
908 dev_dbg(&priv->spi->dev, "SFD for RX\n");
909 }
910
911 return IRQ_HANDLED;
912 }
913
cc2520_get_platform_data(struct spi_device * spi,struct cc2520_platform_data * pdata)914 static int cc2520_get_platform_data(struct spi_device *spi,
915 struct cc2520_platform_data *pdata)
916 {
917 struct device_node *np = spi->dev.of_node;
918 struct cc2520_private *priv = spi_get_drvdata(spi);
919
920 if (!np) {
921 struct cc2520_platform_data *spi_pdata = spi->dev.platform_data;
922
923 if (!spi_pdata)
924 return -ENOENT;
925 *pdata = *spi_pdata;
926 priv->fifo_pin = pdata->fifo;
927 return 0;
928 }
929
930 pdata->fifo = of_get_named_gpio(np, "fifo-gpio", 0);
931 priv->fifo_pin = pdata->fifo;
932
933 pdata->fifop = of_get_named_gpio(np, "fifop-gpio", 0);
934
935 pdata->sfd = of_get_named_gpio(np, "sfd-gpio", 0);
936 pdata->cca = of_get_named_gpio(np, "cca-gpio", 0);
937 pdata->vreg = of_get_named_gpio(np, "vreg-gpio", 0);
938 pdata->reset = of_get_named_gpio(np, "reset-gpio", 0);
939
940 /* CC2591 front end for CC2520 */
941 if (of_property_read_bool(np, "amplified"))
942 priv->amplified = true;
943
944 return 0;
945 }
946
cc2520_hw_init(struct cc2520_private * priv)947 static int cc2520_hw_init(struct cc2520_private *priv)
948 {
949 u8 status = 0, state = 0xff;
950 int ret;
951 int timeout = 100;
952 struct cc2520_platform_data pdata;
953
954 ret = cc2520_get_platform_data(priv->spi, &pdata);
955 if (ret)
956 goto err_ret;
957
958 ret = cc2520_read_register(priv, CC2520_FSMSTAT1, &state);
959 if (ret)
960 goto err_ret;
961
962 if (state != STATE_IDLE)
963 return -EINVAL;
964
965 do {
966 ret = cc2520_get_status(priv, &status);
967 if (ret)
968 goto err_ret;
969
970 if (timeout-- <= 0) {
971 dev_err(&priv->spi->dev, "oscillator start failed!\n");
972 return ret;
973 }
974 udelay(1);
975 } while (!(status & CC2520_STATUS_XOSC32M_STABLE));
976
977 dev_vdbg(&priv->spi->dev, "oscillator brought up\n");
978
979 /* If the CC2520 is connected to a CC2591 amplifier, we must both
980 * configure GPIOs on the CC2520 to correctly configure the CC2591
981 * and change a couple settings of the CC2520 to work with the
982 * amplifier. See section 8 page 17 of TI application note AN065.
983 * http://www.ti.com/lit/an/swra229a/swra229a.pdf
984 */
985 if (priv->amplified) {
986 ret = cc2520_write_register(priv, CC2520_AGCCTRL1, 0x16);
987 if (ret)
988 goto err_ret;
989
990 ret = cc2520_write_register(priv, CC2520_GPIOCTRL0, 0x46);
991 if (ret)
992 goto err_ret;
993
994 ret = cc2520_write_register(priv, CC2520_GPIOCTRL5, 0x47);
995 if (ret)
996 goto err_ret;
997
998 ret = cc2520_write_register(priv, CC2520_GPIOPOLARITY, 0x1e);
999 if (ret)
1000 goto err_ret;
1001
1002 ret = cc2520_write_register(priv, CC2520_TXCTRL, 0xc1);
1003 if (ret)
1004 goto err_ret;
1005 } else {
1006 ret = cc2520_write_register(priv, CC2520_AGCCTRL1, 0x11);
1007 if (ret)
1008 goto err_ret;
1009 }
1010
1011 /* Registers default value: section 28.1 in Datasheet */
1012
1013 /* Set the CCA threshold to -50 dBm. This seems to have been copied
1014 * from the TinyOS CC2520 driver and is much higher than the -84 dBm
1015 * threshold suggested in the datasheet.
1016 */
1017 ret = cc2520_write_register(priv, CC2520_CCACTRL0, 0x1A);
1018 if (ret)
1019 goto err_ret;
1020
1021 ret = cc2520_write_register(priv, CC2520_MDMCTRL0, 0x85);
1022 if (ret)
1023 goto err_ret;
1024
1025 ret = cc2520_write_register(priv, CC2520_MDMCTRL1, 0x14);
1026 if (ret)
1027 goto err_ret;
1028
1029 ret = cc2520_write_register(priv, CC2520_RXCTRL, 0x3f);
1030 if (ret)
1031 goto err_ret;
1032
1033 ret = cc2520_write_register(priv, CC2520_FSCTRL, 0x5a);
1034 if (ret)
1035 goto err_ret;
1036
1037 ret = cc2520_write_register(priv, CC2520_FSCAL1, 0x2b);
1038 if (ret)
1039 goto err_ret;
1040
1041 ret = cc2520_write_register(priv, CC2520_ADCTEST0, 0x10);
1042 if (ret)
1043 goto err_ret;
1044
1045 ret = cc2520_write_register(priv, CC2520_ADCTEST1, 0x0e);
1046 if (ret)
1047 goto err_ret;
1048
1049 ret = cc2520_write_register(priv, CC2520_ADCTEST2, 0x03);
1050 if (ret)
1051 goto err_ret;
1052
1053 /* Configure registers correctly for this driver. */
1054 ret = cc2520_write_register(priv, CC2520_FRMCTRL1,
1055 FRMCTRL1_SET_RXENMASK_ON_TX |
1056 FRMCTRL1_IGNORE_TX_UNDERF);
1057 if (ret)
1058 goto err_ret;
1059
1060 ret = cc2520_write_register(priv, CC2520_FIFOPCTRL, 127);
1061 if (ret)
1062 goto err_ret;
1063
1064 return 0;
1065
1066 err_ret:
1067 return ret;
1068 }
1069
cc2520_probe(struct spi_device * spi)1070 static int cc2520_probe(struct spi_device *spi)
1071 {
1072 struct cc2520_private *priv;
1073 struct cc2520_platform_data pdata;
1074 int ret;
1075
1076 priv = devm_kzalloc(&spi->dev, sizeof(*priv), GFP_KERNEL);
1077 if (!priv)
1078 return -ENOMEM;
1079
1080 spi_set_drvdata(spi, priv);
1081
1082 ret = cc2520_get_platform_data(spi, &pdata);
1083 if (ret < 0) {
1084 dev_err(&spi->dev, "no platform data\n");
1085 return -EINVAL;
1086 }
1087
1088 priv->spi = spi;
1089
1090 priv->buf = devm_kzalloc(&spi->dev,
1091 SPI_COMMAND_BUFFER, GFP_KERNEL);
1092 if (!priv->buf)
1093 return -ENOMEM;
1094
1095 mutex_init(&priv->buffer_mutex);
1096 INIT_WORK(&priv->fifop_irqwork, cc2520_fifop_irqwork);
1097 spin_lock_init(&priv->lock);
1098 init_completion(&priv->tx_complete);
1099
1100 /* Assumption that CC2591 is not connected */
1101 priv->amplified = false;
1102
1103 /* Request all the gpio's */
1104 if (!gpio_is_valid(pdata.fifo)) {
1105 dev_err(&spi->dev, "fifo gpio is not valid\n");
1106 ret = -EINVAL;
1107 goto err_hw_init;
1108 }
1109
1110 ret = devm_gpio_request_one(&spi->dev, pdata.fifo,
1111 GPIOF_IN, "fifo");
1112 if (ret)
1113 goto err_hw_init;
1114
1115 if (!gpio_is_valid(pdata.cca)) {
1116 dev_err(&spi->dev, "cca gpio is not valid\n");
1117 ret = -EINVAL;
1118 goto err_hw_init;
1119 }
1120
1121 ret = devm_gpio_request_one(&spi->dev, pdata.cca,
1122 GPIOF_IN, "cca");
1123 if (ret)
1124 goto err_hw_init;
1125
1126 if (!gpio_is_valid(pdata.fifop)) {
1127 dev_err(&spi->dev, "fifop gpio is not valid\n");
1128 ret = -EINVAL;
1129 goto err_hw_init;
1130 }
1131
1132 ret = devm_gpio_request_one(&spi->dev, pdata.fifop,
1133 GPIOF_IN, "fifop");
1134 if (ret)
1135 goto err_hw_init;
1136
1137 if (!gpio_is_valid(pdata.sfd)) {
1138 dev_err(&spi->dev, "sfd gpio is not valid\n");
1139 ret = -EINVAL;
1140 goto err_hw_init;
1141 }
1142
1143 ret = devm_gpio_request_one(&spi->dev, pdata.sfd,
1144 GPIOF_IN, "sfd");
1145 if (ret)
1146 goto err_hw_init;
1147
1148 if (!gpio_is_valid(pdata.reset)) {
1149 dev_err(&spi->dev, "reset gpio is not valid\n");
1150 ret = -EINVAL;
1151 goto err_hw_init;
1152 }
1153
1154 ret = devm_gpio_request_one(&spi->dev, pdata.reset,
1155 GPIOF_OUT_INIT_LOW, "reset");
1156 if (ret)
1157 goto err_hw_init;
1158
1159 if (!gpio_is_valid(pdata.vreg)) {
1160 dev_err(&spi->dev, "vreg gpio is not valid\n");
1161 ret = -EINVAL;
1162 goto err_hw_init;
1163 }
1164
1165 ret = devm_gpio_request_one(&spi->dev, pdata.vreg,
1166 GPIOF_OUT_INIT_LOW, "vreg");
1167 if (ret)
1168 goto err_hw_init;
1169
1170 gpio_set_value(pdata.vreg, HIGH);
1171 usleep_range(100, 150);
1172
1173 gpio_set_value(pdata.reset, HIGH);
1174 usleep_range(200, 250);
1175
1176 ret = cc2520_hw_init(priv);
1177 if (ret)
1178 goto err_hw_init;
1179
1180 /* Set up fifop interrupt */
1181 ret = devm_request_irq(&spi->dev,
1182 gpio_to_irq(pdata.fifop),
1183 cc2520_fifop_isr,
1184 IRQF_TRIGGER_RISING,
1185 dev_name(&spi->dev),
1186 priv);
1187 if (ret) {
1188 dev_err(&spi->dev, "could not get fifop irq\n");
1189 goto err_hw_init;
1190 }
1191
1192 /* Set up sfd interrupt */
1193 ret = devm_request_irq(&spi->dev,
1194 gpio_to_irq(pdata.sfd),
1195 cc2520_sfd_isr,
1196 IRQF_TRIGGER_FALLING,
1197 dev_name(&spi->dev),
1198 priv);
1199 if (ret) {
1200 dev_err(&spi->dev, "could not get sfd irq\n");
1201 goto err_hw_init;
1202 }
1203
1204 ret = cc2520_register(priv);
1205 if (ret)
1206 goto err_hw_init;
1207
1208 return 0;
1209
1210 err_hw_init:
1211 mutex_destroy(&priv->buffer_mutex);
1212 flush_work(&priv->fifop_irqwork);
1213 return ret;
1214 }
1215
cc2520_remove(struct spi_device * spi)1216 static int cc2520_remove(struct spi_device *spi)
1217 {
1218 struct cc2520_private *priv = spi_get_drvdata(spi);
1219
1220 mutex_destroy(&priv->buffer_mutex);
1221 flush_work(&priv->fifop_irqwork);
1222
1223 ieee802154_unregister_hw(priv->hw);
1224 ieee802154_free_hw(priv->hw);
1225
1226 return 0;
1227 }
1228
1229 static const struct spi_device_id cc2520_ids[] = {
1230 {"cc2520", },
1231 {},
1232 };
1233 MODULE_DEVICE_TABLE(spi, cc2520_ids);
1234
1235 static const struct of_device_id cc2520_of_ids[] = {
1236 {.compatible = "ti,cc2520", },
1237 {},
1238 };
1239 MODULE_DEVICE_TABLE(of, cc2520_of_ids);
1240
1241 /* SPI driver structure */
1242 static struct spi_driver cc2520_driver = {
1243 .driver = {
1244 .name = "cc2520",
1245 .of_match_table = of_match_ptr(cc2520_of_ids),
1246 },
1247 .id_table = cc2520_ids,
1248 .probe = cc2520_probe,
1249 .remove = cc2520_remove,
1250 };
1251 module_spi_driver(cc2520_driver);
1252
1253 MODULE_AUTHOR("Varka Bhadram <varkab@cdac.in>");
1254 MODULE_DESCRIPTION("CC2520 Transceiver Driver");
1255 MODULE_LICENSE("GPL v2");
1256