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/consumer.h>
11 #include <linux/delay.h>
12 #include <linux/spi/spi.h>
13 #include <linux/property.h>
14 #include <linux/workqueue.h>
15 #include <linux/interrupt.h>
16 #include <linux/skbuff.h>
17 #include <linux/ieee802154.h>
18 #include <linux/crc-ccitt.h>
19 #include <linux/unaligned.h>
20
21 #include <net/mac802154.h>
22 #include <net/cfg802154.h>
23
24 #define SPI_COMMAND_BUFFER 3
25 #define HIGH 1
26 #define LOW 0
27 #define STATE_IDLE 0
28 #define RSSI_VALID 0
29 #define RSSI_OFFSET 78
30
31 #define CC2520_RAM_SIZE 640
32 #define CC2520_FIFO_SIZE 128
33
34 #define CC2520RAM_TXFIFO 0x100
35 #define CC2520RAM_RXFIFO 0x180
36 #define CC2520RAM_IEEEADDR 0x3EA
37 #define CC2520RAM_PANID 0x3F2
38 #define CC2520RAM_SHORTADDR 0x3F4
39
40 #define CC2520_FREG_MASK 0x3F
41
42 /* status byte values */
43 #define CC2520_STATUS_XOSC32M_STABLE BIT(7)
44 #define CC2520_STATUS_RSSI_VALID BIT(6)
45 #define CC2520_STATUS_TX_UNDERFLOW BIT(3)
46
47 /* IEEE-802.15.4 defined constants (2.4 GHz logical channels) */
48 #define CC2520_MINCHANNEL 11
49 #define CC2520_MAXCHANNEL 26
50 #define CC2520_CHANNEL_SPACING 5
51
52 /* command strobes */
53 #define CC2520_CMD_SNOP 0x00
54 #define CC2520_CMD_IBUFLD 0x02
55 #define CC2520_CMD_SIBUFEX 0x03
56 #define CC2520_CMD_SSAMPLECCA 0x04
57 #define CC2520_CMD_SRES 0x0f
58 #define CC2520_CMD_MEMORY_MASK 0x0f
59 #define CC2520_CMD_MEMORY_READ 0x10
60 #define CC2520_CMD_MEMORY_WRITE 0x20
61 #define CC2520_CMD_RXBUF 0x30
62 #define CC2520_CMD_RXBUFCP 0x38
63 #define CC2520_CMD_RXBUFMOV 0x32
64 #define CC2520_CMD_TXBUF 0x3A
65 #define CC2520_CMD_TXBUFCP 0x3E
66 #define CC2520_CMD_RANDOM 0x3C
67 #define CC2520_CMD_SXOSCON 0x40
68 #define CC2520_CMD_STXCAL 0x41
69 #define CC2520_CMD_SRXON 0x42
70 #define CC2520_CMD_STXON 0x43
71 #define CC2520_CMD_STXONCCA 0x44
72 #define CC2520_CMD_SRFOFF 0x45
73 #define CC2520_CMD_SXOSCOFF 0x46
74 #define CC2520_CMD_SFLUSHRX 0x47
75 #define CC2520_CMD_SFLUSHTX 0x48
76 #define CC2520_CMD_SACK 0x49
77 #define CC2520_CMD_SACKPEND 0x4A
78 #define CC2520_CMD_SNACK 0x4B
79 #define CC2520_CMD_SRXMASKBITSET 0x4C
80 #define CC2520_CMD_SRXMASKBITCLR 0x4D
81 #define CC2520_CMD_RXMASKAND 0x4E
82 #define CC2520_CMD_RXMASKOR 0x4F
83 #define CC2520_CMD_MEMCP 0x50
84 #define CC2520_CMD_MEMCPR 0x52
85 #define CC2520_CMD_MEMXCP 0x54
86 #define CC2520_CMD_MEMXWR 0x56
87 #define CC2520_CMD_BCLR 0x58
88 #define CC2520_CMD_BSET 0x59
89 #define CC2520_CMD_CTR_UCTR 0x60
90 #define CC2520_CMD_CBCMAC 0x64
91 #define CC2520_CMD_UCBCMAC 0x66
92 #define CC2520_CMD_CCM 0x68
93 #define CC2520_CMD_UCCM 0x6A
94 #define CC2520_CMD_ECB 0x70
95 #define CC2520_CMD_ECBO 0x72
96 #define CC2520_CMD_ECBX 0x74
97 #define CC2520_CMD_INC 0x78
98 #define CC2520_CMD_ABORT 0x7F
99 #define CC2520_CMD_REGISTER_READ 0x80
100 #define CC2520_CMD_REGISTER_WRITE 0xC0
101
102 /* status registers */
103 #define CC2520_CHIPID 0x40
104 #define CC2520_VERSION 0x42
105 #define CC2520_EXTCLOCK 0x44
106 #define CC2520_MDMCTRL0 0x46
107 #define CC2520_MDMCTRL1 0x47
108 #define CC2520_FREQEST 0x48
109 #define CC2520_RXCTRL 0x4A
110 #define CC2520_FSCTRL 0x4C
111 #define CC2520_FSCAL0 0x4E
112 #define CC2520_FSCAL1 0x4F
113 #define CC2520_FSCAL2 0x50
114 #define CC2520_FSCAL3 0x51
115 #define CC2520_AGCCTRL0 0x52
116 #define CC2520_AGCCTRL1 0x53
117 #define CC2520_AGCCTRL2 0x54
118 #define CC2520_AGCCTRL3 0x55
119 #define CC2520_ADCTEST0 0x56
120 #define CC2520_ADCTEST1 0x57
121 #define CC2520_ADCTEST2 0x58
122 #define CC2520_MDMTEST0 0x5A
123 #define CC2520_MDMTEST1 0x5B
124 #define CC2520_DACTEST0 0x5C
125 #define CC2520_DACTEST1 0x5D
126 #define CC2520_ATEST 0x5E
127 #define CC2520_DACTEST2 0x5F
128 #define CC2520_PTEST0 0x60
129 #define CC2520_PTEST1 0x61
130 #define CC2520_RESERVED 0x62
131 #define CC2520_DPUBIST 0x7A
132 #define CC2520_ACTBIST 0x7C
133 #define CC2520_RAMBIST 0x7E
134
135 /* frame registers */
136 #define CC2520_FRMFILT0 0x00
137 #define CC2520_FRMFILT1 0x01
138 #define CC2520_SRCMATCH 0x02
139 #define CC2520_SRCSHORTEN0 0x04
140 #define CC2520_SRCSHORTEN1 0x05
141 #define CC2520_SRCSHORTEN2 0x06
142 #define CC2520_SRCEXTEN0 0x08
143 #define CC2520_SRCEXTEN1 0x09
144 #define CC2520_SRCEXTEN2 0x0A
145 #define CC2520_FRMCTRL0 0x0C
146 #define CC2520_FRMCTRL1 0x0D
147 #define CC2520_RXENABLE0 0x0E
148 #define CC2520_RXENABLE1 0x0F
149 #define CC2520_EXCFLAG0 0x10
150 #define CC2520_EXCFLAG1 0x11
151 #define CC2520_EXCFLAG2 0x12
152 #define CC2520_EXCMASKA0 0x14
153 #define CC2520_EXCMASKA1 0x15
154 #define CC2520_EXCMASKA2 0x16
155 #define CC2520_EXCMASKB0 0x18
156 #define CC2520_EXCMASKB1 0x19
157 #define CC2520_EXCMASKB2 0x1A
158 #define CC2520_EXCBINDX0 0x1C
159 #define CC2520_EXCBINDX1 0x1D
160 #define CC2520_EXCBINDY0 0x1E
161 #define CC2520_EXCBINDY1 0x1F
162 #define CC2520_GPIOCTRL0 0x20
163 #define CC2520_GPIOCTRL1 0x21
164 #define CC2520_GPIOCTRL2 0x22
165 #define CC2520_GPIOCTRL3 0x23
166 #define CC2520_GPIOCTRL4 0x24
167 #define CC2520_GPIOCTRL5 0x25
168 #define CC2520_GPIOPOLARITY 0x26
169 #define CC2520_GPIOCTRL 0x28
170 #define CC2520_DPUCON 0x2A
171 #define CC2520_DPUSTAT 0x2C
172 #define CC2520_FREQCTRL 0x2E
173 #define CC2520_FREQTUNE 0x2F
174 #define CC2520_TXPOWER 0x30
175 #define CC2520_TXCTRL 0x31
176 #define CC2520_FSMSTAT0 0x32
177 #define CC2520_FSMSTAT1 0x33
178 #define CC2520_FIFOPCTRL 0x34
179 #define CC2520_FSMCTRL 0x35
180 #define CC2520_CCACTRL0 0x36
181 #define CC2520_CCACTRL1 0x37
182 #define CC2520_RSSI 0x38
183 #define CC2520_RSSISTAT 0x39
184 #define CC2520_RXFIRST 0x3C
185 #define CC2520_RXFIFOCNT 0x3E
186 #define CC2520_TXFIFOCNT 0x3F
187
188 /* CC2520_FRMFILT0 */
189 #define FRMFILT0_FRAME_FILTER_EN BIT(0)
190 #define FRMFILT0_PAN_COORDINATOR BIT(1)
191
192 /* CC2520_FRMCTRL0 */
193 #define FRMCTRL0_AUTOACK BIT(5)
194 #define FRMCTRL0_AUTOCRC BIT(6)
195
196 /* CC2520_FRMCTRL1 */
197 #define FRMCTRL1_SET_RXENMASK_ON_TX BIT(0)
198 #define FRMCTRL1_IGNORE_TX_UNDERF BIT(1)
199
200 /* Driver private information */
201 struct cc2520_private {
202 struct spi_device *spi; /* SPI device structure */
203 struct ieee802154_hw *hw; /* IEEE-802.15.4 device */
204 u8 *buf; /* SPI TX/Rx data buffer */
205 struct mutex buffer_mutex; /* SPI buffer mutex */
206 bool is_tx; /* Flag for sync b/w Tx and Rx */
207 bool amplified; /* Flag for CC2591 */
208 struct gpio_desc *fifo_pin; /* FIFO GPIO pin number */
209 struct work_struct fifop_irqwork;/* Workqueue for FIFOP */
210 spinlock_t lock; /* Lock for is_tx*/
211 struct completion tx_complete; /* Work completion for Tx */
212 bool promiscuous; /* Flag for promiscuous mode */
213 };
214
215 /* Generic Functions */
216 static int
cc2520_cmd_strobe(struct cc2520_private * priv,u8 cmd)217 cc2520_cmd_strobe(struct cc2520_private *priv, u8 cmd)
218 {
219 int ret;
220 struct spi_message msg;
221 struct spi_transfer xfer = {
222 .len = 0,
223 .tx_buf = priv->buf,
224 .rx_buf = priv->buf,
225 };
226
227 spi_message_init(&msg);
228 spi_message_add_tail(&xfer, &msg);
229
230 mutex_lock(&priv->buffer_mutex);
231 priv->buf[xfer.len++] = cmd;
232 dev_vdbg(&priv->spi->dev,
233 "command strobe buf[0] = %02x\n",
234 priv->buf[0]);
235
236 ret = spi_sync(priv->spi, &msg);
237 dev_vdbg(&priv->spi->dev,
238 "buf[0] = %02x\n", priv->buf[0]);
239 mutex_unlock(&priv->buffer_mutex);
240
241 return ret;
242 }
243
244 static int
cc2520_get_status(struct cc2520_private * priv,u8 * status)245 cc2520_get_status(struct cc2520_private *priv, u8 *status)
246 {
247 int ret;
248 struct spi_message msg;
249 struct spi_transfer xfer = {
250 .len = 0,
251 .tx_buf = priv->buf,
252 .rx_buf = priv->buf,
253 };
254
255 spi_message_init(&msg);
256 spi_message_add_tail(&xfer, &msg);
257
258 mutex_lock(&priv->buffer_mutex);
259 priv->buf[xfer.len++] = CC2520_CMD_SNOP;
260 dev_vdbg(&priv->spi->dev,
261 "get status command buf[0] = %02x\n", priv->buf[0]);
262
263 ret = spi_sync(priv->spi, &msg);
264 if (!ret)
265 *status = priv->buf[0];
266 dev_vdbg(&priv->spi->dev,
267 "buf[0] = %02x\n", priv->buf[0]);
268 mutex_unlock(&priv->buffer_mutex);
269
270 return ret;
271 }
272
273 static int
cc2520_write_register(struct cc2520_private * priv,u8 reg,u8 value)274 cc2520_write_register(struct cc2520_private *priv, u8 reg, u8 value)
275 {
276 int status;
277 struct spi_message msg;
278 struct spi_transfer xfer = {
279 .len = 0,
280 .tx_buf = priv->buf,
281 .rx_buf = priv->buf,
282 };
283
284 spi_message_init(&msg);
285 spi_message_add_tail(&xfer, &msg);
286
287 mutex_lock(&priv->buffer_mutex);
288
289 if (reg <= CC2520_FREG_MASK) {
290 priv->buf[xfer.len++] = CC2520_CMD_REGISTER_WRITE | reg;
291 priv->buf[xfer.len++] = value;
292 } else {
293 priv->buf[xfer.len++] = CC2520_CMD_MEMORY_WRITE;
294 priv->buf[xfer.len++] = reg;
295 priv->buf[xfer.len++] = value;
296 }
297 status = spi_sync(priv->spi, &msg);
298 if (msg.status)
299 status = msg.status;
300
301 mutex_unlock(&priv->buffer_mutex);
302
303 return status;
304 }
305
306 static int
cc2520_write_ram(struct cc2520_private * priv,u16 reg,u8 len,u8 * data)307 cc2520_write_ram(struct cc2520_private *priv, u16 reg, u8 len, u8 *data)
308 {
309 int status;
310 struct spi_message msg;
311 struct spi_transfer xfer_head = {
312 .len = 0,
313 .tx_buf = priv->buf,
314 .rx_buf = priv->buf,
315 };
316
317 struct spi_transfer xfer_buf = {
318 .len = len,
319 .tx_buf = data,
320 };
321
322 mutex_lock(&priv->buffer_mutex);
323 priv->buf[xfer_head.len++] = (CC2520_CMD_MEMORY_WRITE |
324 ((reg >> 8) & 0xff));
325 priv->buf[xfer_head.len++] = reg & 0xff;
326
327 spi_message_init(&msg);
328 spi_message_add_tail(&xfer_head, &msg);
329 spi_message_add_tail(&xfer_buf, &msg);
330
331 status = spi_sync(priv->spi, &msg);
332 dev_dbg(&priv->spi->dev, "spi status = %d\n", status);
333 if (msg.status)
334 status = msg.status;
335
336 mutex_unlock(&priv->buffer_mutex);
337 return status;
338 }
339
340 static int
cc2520_read_register(struct cc2520_private * priv,u8 reg,u8 * data)341 cc2520_read_register(struct cc2520_private *priv, u8 reg, u8 *data)
342 {
343 int status;
344 struct spi_message msg;
345 struct spi_transfer xfer1 = {
346 .len = 0,
347 .tx_buf = priv->buf,
348 .rx_buf = priv->buf,
349 };
350
351 struct spi_transfer xfer2 = {
352 .len = 1,
353 .rx_buf = data,
354 };
355
356 spi_message_init(&msg);
357 spi_message_add_tail(&xfer1, &msg);
358 spi_message_add_tail(&xfer2, &msg);
359
360 mutex_lock(&priv->buffer_mutex);
361 priv->buf[xfer1.len++] = CC2520_CMD_MEMORY_READ;
362 priv->buf[xfer1.len++] = reg;
363
364 status = spi_sync(priv->spi, &msg);
365 dev_dbg(&priv->spi->dev,
366 "spi status = %d\n", status);
367 if (msg.status)
368 status = msg.status;
369
370 mutex_unlock(&priv->buffer_mutex);
371
372 return status;
373 }
374
375 static int
cc2520_write_txfifo(struct cc2520_private * priv,u8 pkt_len,u8 * data,u8 len)376 cc2520_write_txfifo(struct cc2520_private *priv, u8 pkt_len, u8 *data, u8 len)
377 {
378 int status;
379
380 /* length byte must include FCS even
381 * if it is calculated in the hardware
382 */
383 int len_byte = pkt_len;
384
385 struct spi_message msg;
386
387 struct spi_transfer xfer_head = {
388 .len = 0,
389 .tx_buf = priv->buf,
390 .rx_buf = priv->buf,
391 };
392 struct spi_transfer xfer_len = {
393 .len = 1,
394 .tx_buf = &len_byte,
395 };
396 struct spi_transfer xfer_buf = {
397 .len = len,
398 .tx_buf = data,
399 };
400
401 spi_message_init(&msg);
402 spi_message_add_tail(&xfer_head, &msg);
403 spi_message_add_tail(&xfer_len, &msg);
404 spi_message_add_tail(&xfer_buf, &msg);
405
406 mutex_lock(&priv->buffer_mutex);
407 priv->buf[xfer_head.len++] = CC2520_CMD_TXBUF;
408 dev_vdbg(&priv->spi->dev,
409 "TX_FIFO cmd buf[0] = %02x\n", priv->buf[0]);
410
411 status = spi_sync(priv->spi, &msg);
412 dev_vdbg(&priv->spi->dev, "status = %d\n", status);
413 if (msg.status)
414 status = msg.status;
415 dev_vdbg(&priv->spi->dev, "status = %d\n", status);
416 dev_vdbg(&priv->spi->dev, "buf[0] = %02x\n", priv->buf[0]);
417 mutex_unlock(&priv->buffer_mutex);
418
419 return status;
420 }
421
422 static int
cc2520_read_rxfifo(struct cc2520_private * priv,u8 * data,u8 len)423 cc2520_read_rxfifo(struct cc2520_private *priv, u8 *data, u8 len)
424 {
425 int status;
426 struct spi_message msg;
427
428 struct spi_transfer xfer_head = {
429 .len = 0,
430 .tx_buf = priv->buf,
431 .rx_buf = priv->buf,
432 };
433 struct spi_transfer xfer_buf = {
434 .len = len,
435 .rx_buf = data,
436 };
437
438 spi_message_init(&msg);
439 spi_message_add_tail(&xfer_head, &msg);
440 spi_message_add_tail(&xfer_buf, &msg);
441
442 mutex_lock(&priv->buffer_mutex);
443 priv->buf[xfer_head.len++] = CC2520_CMD_RXBUF;
444
445 dev_vdbg(&priv->spi->dev, "read rxfifo buf[0] = %02x\n", priv->buf[0]);
446 dev_vdbg(&priv->spi->dev, "buf[1] = %02x\n", priv->buf[1]);
447
448 status = spi_sync(priv->spi, &msg);
449 dev_vdbg(&priv->spi->dev, "status = %d\n", status);
450 if (msg.status)
451 status = msg.status;
452 dev_vdbg(&priv->spi->dev, "status = %d\n", status);
453 dev_vdbg(&priv->spi->dev,
454 "return status buf[0] = %02x\n", priv->buf[0]);
455 dev_vdbg(&priv->spi->dev, "length buf[1] = %02x\n", priv->buf[1]);
456
457 mutex_unlock(&priv->buffer_mutex);
458
459 return status;
460 }
461
cc2520_start(struct ieee802154_hw * hw)462 static int cc2520_start(struct ieee802154_hw *hw)
463 {
464 return cc2520_cmd_strobe(hw->priv, CC2520_CMD_SRXON);
465 }
466
cc2520_stop(struct ieee802154_hw * hw)467 static void cc2520_stop(struct ieee802154_hw *hw)
468 {
469 cc2520_cmd_strobe(hw->priv, CC2520_CMD_SRFOFF);
470 }
471
472 static int
cc2520_tx(struct ieee802154_hw * hw,struct sk_buff * skb)473 cc2520_tx(struct ieee802154_hw *hw, struct sk_buff *skb)
474 {
475 struct cc2520_private *priv = hw->priv;
476 unsigned long flags;
477 int rc;
478 u8 status = 0;
479 u8 pkt_len;
480
481 /* In promiscuous mode we disable AUTOCRC so we can get the raw CRC
482 * values on RX. This means we need to manually add the CRC on TX.
483 */
484 if (priv->promiscuous) {
485 u16 crc = crc_ccitt(0, skb->data, skb->len);
486
487 put_unaligned_le16(crc, skb_put(skb, 2));
488 pkt_len = skb->len;
489 } else {
490 pkt_len = skb->len + 2;
491 }
492
493 rc = cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHTX);
494 if (rc)
495 goto err_tx;
496
497 rc = cc2520_write_txfifo(priv, pkt_len, skb->data, skb->len);
498 if (rc)
499 goto err_tx;
500
501 rc = cc2520_get_status(priv, &status);
502 if (rc)
503 goto err_tx;
504
505 if (status & CC2520_STATUS_TX_UNDERFLOW) {
506 rc = -EINVAL;
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 (gpiod_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_hw_init(struct cc2520_private * priv)914 static int cc2520_hw_init(struct cc2520_private *priv)
915 {
916 u8 status = 0, state = 0xff;
917 int ret;
918 int timeout = 100;
919
920 ret = cc2520_read_register(priv, CC2520_FSMSTAT1, &state);
921 if (ret)
922 goto err_ret;
923
924 if (state != STATE_IDLE)
925 return -EINVAL;
926
927 do {
928 ret = cc2520_get_status(priv, &status);
929 if (ret)
930 goto err_ret;
931
932 if (timeout-- <= 0) {
933 dev_err(&priv->spi->dev, "oscillator start failed!\n");
934 return -ETIMEDOUT;
935 }
936 udelay(1);
937 } while (!(status & CC2520_STATUS_XOSC32M_STABLE));
938
939 dev_vdbg(&priv->spi->dev, "oscillator brought up\n");
940
941 /* If the CC2520 is connected to a CC2591 amplifier, we must both
942 * configure GPIOs on the CC2520 to correctly configure the CC2591
943 * and change a couple settings of the CC2520 to work with the
944 * amplifier. See section 8 page 17 of TI application note AN065.
945 * http://www.ti.com/lit/an/swra229a/swra229a.pdf
946 */
947 if (priv->amplified) {
948 ret = cc2520_write_register(priv, CC2520_AGCCTRL1, 0x16);
949 if (ret)
950 goto err_ret;
951
952 ret = cc2520_write_register(priv, CC2520_GPIOCTRL0, 0x46);
953 if (ret)
954 goto err_ret;
955
956 ret = cc2520_write_register(priv, CC2520_GPIOCTRL5, 0x47);
957 if (ret)
958 goto err_ret;
959
960 ret = cc2520_write_register(priv, CC2520_GPIOPOLARITY, 0x1e);
961 if (ret)
962 goto err_ret;
963
964 ret = cc2520_write_register(priv, CC2520_TXCTRL, 0xc1);
965 if (ret)
966 goto err_ret;
967 } else {
968 ret = cc2520_write_register(priv, CC2520_AGCCTRL1, 0x11);
969 if (ret)
970 goto err_ret;
971 }
972
973 /* Registers default value: section 28.1 in Datasheet */
974
975 /* Set the CCA threshold to -50 dBm. This seems to have been copied
976 * from the TinyOS CC2520 driver and is much higher than the -84 dBm
977 * threshold suggested in the datasheet.
978 */
979 ret = cc2520_write_register(priv, CC2520_CCACTRL0, 0x1A);
980 if (ret)
981 goto err_ret;
982
983 ret = cc2520_write_register(priv, CC2520_MDMCTRL0, 0x85);
984 if (ret)
985 goto err_ret;
986
987 ret = cc2520_write_register(priv, CC2520_MDMCTRL1, 0x14);
988 if (ret)
989 goto err_ret;
990
991 ret = cc2520_write_register(priv, CC2520_RXCTRL, 0x3f);
992 if (ret)
993 goto err_ret;
994
995 ret = cc2520_write_register(priv, CC2520_FSCTRL, 0x5a);
996 if (ret)
997 goto err_ret;
998
999 ret = cc2520_write_register(priv, CC2520_FSCAL1, 0x2b);
1000 if (ret)
1001 goto err_ret;
1002
1003 ret = cc2520_write_register(priv, CC2520_ADCTEST0, 0x10);
1004 if (ret)
1005 goto err_ret;
1006
1007 ret = cc2520_write_register(priv, CC2520_ADCTEST1, 0x0e);
1008 if (ret)
1009 goto err_ret;
1010
1011 ret = cc2520_write_register(priv, CC2520_ADCTEST2, 0x03);
1012 if (ret)
1013 goto err_ret;
1014
1015 /* Configure registers correctly for this driver. */
1016 ret = cc2520_write_register(priv, CC2520_FRMCTRL1,
1017 FRMCTRL1_SET_RXENMASK_ON_TX |
1018 FRMCTRL1_IGNORE_TX_UNDERF);
1019 if (ret)
1020 goto err_ret;
1021
1022 ret = cc2520_write_register(priv, CC2520_FIFOPCTRL, 127);
1023 if (ret)
1024 goto err_ret;
1025
1026 return 0;
1027
1028 err_ret:
1029 return ret;
1030 }
1031
cc2520_probe(struct spi_device * spi)1032 static int cc2520_probe(struct spi_device *spi)
1033 {
1034 struct cc2520_private *priv;
1035 struct gpio_desc *fifop;
1036 struct gpio_desc *cca;
1037 struct gpio_desc *sfd;
1038 struct gpio_desc *reset;
1039 struct gpio_desc *vreg;
1040 int ret;
1041
1042 priv = devm_kzalloc(&spi->dev, sizeof(*priv), GFP_KERNEL);
1043 if (!priv)
1044 return -ENOMEM;
1045
1046 spi_set_drvdata(spi, priv);
1047
1048 /* CC2591 front end for CC2520 */
1049 /* Assumption that CC2591 is not connected */
1050 priv->amplified = false;
1051 if (device_property_read_bool(&spi->dev, "amplified"))
1052 priv->amplified = true;
1053
1054 priv->spi = spi;
1055
1056 priv->buf = devm_kzalloc(&spi->dev,
1057 SPI_COMMAND_BUFFER, GFP_KERNEL);
1058 if (!priv->buf)
1059 return -ENOMEM;
1060
1061 mutex_init(&priv->buffer_mutex);
1062 INIT_WORK(&priv->fifop_irqwork, cc2520_fifop_irqwork);
1063 spin_lock_init(&priv->lock);
1064 init_completion(&priv->tx_complete);
1065
1066 /* Request all the gpio's */
1067 priv->fifo_pin = devm_gpiod_get(&spi->dev, "fifo", GPIOD_IN);
1068 if (IS_ERR(priv->fifo_pin)) {
1069 dev_err(&spi->dev, "fifo gpio is not valid\n");
1070 ret = PTR_ERR(priv->fifo_pin);
1071 goto err_hw_init;
1072 }
1073
1074 cca = devm_gpiod_get(&spi->dev, "cca", GPIOD_IN);
1075 if (IS_ERR(cca)) {
1076 dev_err(&spi->dev, "cca gpio is not valid\n");
1077 ret = PTR_ERR(cca);
1078 goto err_hw_init;
1079 }
1080
1081 fifop = devm_gpiod_get(&spi->dev, "fifop", GPIOD_IN);
1082 if (IS_ERR(fifop)) {
1083 dev_err(&spi->dev, "fifop gpio is not valid\n");
1084 ret = PTR_ERR(fifop);
1085 goto err_hw_init;
1086 }
1087
1088 sfd = devm_gpiod_get(&spi->dev, "sfd", GPIOD_IN);
1089 if (IS_ERR(sfd)) {
1090 dev_err(&spi->dev, "sfd gpio is not valid\n");
1091 ret = PTR_ERR(sfd);
1092 goto err_hw_init;
1093 }
1094
1095 reset = devm_gpiod_get(&spi->dev, "reset", GPIOD_OUT_LOW);
1096 if (IS_ERR(reset)) {
1097 dev_err(&spi->dev, "reset gpio is not valid\n");
1098 ret = PTR_ERR(reset);
1099 goto err_hw_init;
1100 }
1101
1102 vreg = devm_gpiod_get(&spi->dev, "vreg", GPIOD_OUT_LOW);
1103 if (IS_ERR(vreg)) {
1104 dev_err(&spi->dev, "vreg gpio is not valid\n");
1105 ret = PTR_ERR(vreg);
1106 goto err_hw_init;
1107 }
1108
1109 gpiod_set_value(vreg, HIGH);
1110 usleep_range(100, 150);
1111
1112 gpiod_set_value(reset, HIGH);
1113 usleep_range(200, 250);
1114
1115 ret = cc2520_hw_init(priv);
1116 if (ret)
1117 goto err_hw_init;
1118
1119 /* Set up fifop interrupt */
1120 ret = devm_request_irq(&spi->dev,
1121 gpiod_to_irq(fifop),
1122 cc2520_fifop_isr,
1123 IRQF_TRIGGER_RISING,
1124 dev_name(&spi->dev),
1125 priv);
1126 if (ret) {
1127 dev_err(&spi->dev, "could not get fifop irq\n");
1128 goto err_hw_init;
1129 }
1130
1131 /* Set up sfd interrupt */
1132 ret = devm_request_irq(&spi->dev,
1133 gpiod_to_irq(sfd),
1134 cc2520_sfd_isr,
1135 IRQF_TRIGGER_FALLING,
1136 dev_name(&spi->dev),
1137 priv);
1138 if (ret) {
1139 dev_err(&spi->dev, "could not get sfd irq\n");
1140 goto err_hw_init;
1141 }
1142
1143 ret = cc2520_register(priv);
1144 if (ret)
1145 goto err_hw_init;
1146
1147 return 0;
1148
1149 err_hw_init:
1150 mutex_destroy(&priv->buffer_mutex);
1151 flush_work(&priv->fifop_irqwork);
1152 return ret;
1153 }
1154
cc2520_remove(struct spi_device * spi)1155 static void cc2520_remove(struct spi_device *spi)
1156 {
1157 struct cc2520_private *priv = spi_get_drvdata(spi);
1158
1159 mutex_destroy(&priv->buffer_mutex);
1160 flush_work(&priv->fifop_irqwork);
1161
1162 ieee802154_unregister_hw(priv->hw);
1163 ieee802154_free_hw(priv->hw);
1164 }
1165
1166 static const struct spi_device_id cc2520_ids[] = {
1167 {"cc2520", },
1168 {},
1169 };
1170 MODULE_DEVICE_TABLE(spi, cc2520_ids);
1171
1172 static const struct of_device_id cc2520_of_ids[] = {
1173 {.compatible = "ti,cc2520", },
1174 {},
1175 };
1176 MODULE_DEVICE_TABLE(of, cc2520_of_ids);
1177
1178 /* SPI driver structure */
1179 static struct spi_driver cc2520_driver = {
1180 .driver = {
1181 .name = "cc2520",
1182 .of_match_table = cc2520_of_ids,
1183 },
1184 .id_table = cc2520_ids,
1185 .probe = cc2520_probe,
1186 .remove = cc2520_remove,
1187 };
1188 module_spi_driver(cc2520_driver);
1189
1190 MODULE_AUTHOR("Varka Bhadram <varkab@cdac.in>");
1191 MODULE_DESCRIPTION("CC2520 Transceiver Driver");
1192 MODULE_LICENSE("GPL v2");
1193