GNU Linux-libre 4.9.309-gnu1
[releases.git] / drivers / net / ieee802154 / cc2520.c
1 /* Driver for TI CC2520 802.15.4 Wireless-PAN Networking controller
2  *
3  * Copyright (C) 2014 Varka Bhadram <varkab@cdac.in>
4  *                    Md.Jamal Mohiuddin <mjmohiuddin@cdac.in>
5  *                    P Sowjanya <sowjanyap@cdac.in>
6  *
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.
11  *
12  */
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/gpio.h>
16 #include <linux/delay.h>
17 #include <linux/spi/spi.h>
18 #include <linux/spi/cc2520.h>
19 #include <linux/workqueue.h>
20 #include <linux/interrupt.h>
21 #include <linux/skbuff.h>
22 #include <linux/of_gpio.h>
23 #include <linux/ieee802154.h>
24 #include <linux/crc-ccitt.h>
25 #include <asm/unaligned.h>
26
27 #include <net/mac802154.h>
28 #include <net/cfg802154.h>
29
30 #define SPI_COMMAND_BUFFER      3
31 #define HIGH                    1
32 #define LOW                     0
33 #define STATE_IDLE              0
34 #define RSSI_VALID              0
35 #define RSSI_OFFSET             78
36
37 #define CC2520_RAM_SIZE         640
38 #define CC2520_FIFO_SIZE        128
39
40 #define CC2520RAM_TXFIFO        0x100
41 #define CC2520RAM_RXFIFO        0x180
42 #define CC2520RAM_IEEEADDR      0x3EA
43 #define CC2520RAM_PANID         0x3F2
44 #define CC2520RAM_SHORTADDR     0x3F4
45
46 #define CC2520_FREG_MASK        0x3F
47
48 /* status byte values */
49 #define CC2520_STATUS_XOSC32M_STABLE    BIT(7)
50 #define CC2520_STATUS_RSSI_VALID        BIT(6)
51 #define CC2520_STATUS_TX_UNDERFLOW      BIT(3)
52
53 /* IEEE-802.15.4 defined constants (2.4 GHz logical channels) */
54 #define CC2520_MINCHANNEL               11
55 #define CC2520_MAXCHANNEL               26
56 #define CC2520_CHANNEL_SPACING          5
57
58 /* command strobes */
59 #define CC2520_CMD_SNOP                 0x00
60 #define CC2520_CMD_IBUFLD               0x02
61 #define CC2520_CMD_SIBUFEX              0x03
62 #define CC2520_CMD_SSAMPLECCA           0x04
63 #define CC2520_CMD_SRES                 0x0f
64 #define CC2520_CMD_MEMORY_MASK          0x0f
65 #define CC2520_CMD_MEMORY_READ          0x10
66 #define CC2520_CMD_MEMORY_WRITE         0x20
67 #define CC2520_CMD_RXBUF                0x30
68 #define CC2520_CMD_RXBUFCP              0x38
69 #define CC2520_CMD_RXBUFMOV             0x32
70 #define CC2520_CMD_TXBUF                0x3A
71 #define CC2520_CMD_TXBUFCP              0x3E
72 #define CC2520_CMD_RANDOM               0x3C
73 #define CC2520_CMD_SXOSCON              0x40
74 #define CC2520_CMD_STXCAL               0x41
75 #define CC2520_CMD_SRXON                0x42
76 #define CC2520_CMD_STXON                0x43
77 #define CC2520_CMD_STXONCCA             0x44
78 #define CC2520_CMD_SRFOFF               0x45
79 #define CC2520_CMD_SXOSCOFF             0x46
80 #define CC2520_CMD_SFLUSHRX             0x47
81 #define CC2520_CMD_SFLUSHTX             0x48
82 #define CC2520_CMD_SACK                 0x49
83 #define CC2520_CMD_SACKPEND             0x4A
84 #define CC2520_CMD_SNACK                0x4B
85 #define CC2520_CMD_SRXMASKBITSET        0x4C
86 #define CC2520_CMD_SRXMASKBITCLR        0x4D
87 #define CC2520_CMD_RXMASKAND            0x4E
88 #define CC2520_CMD_RXMASKOR             0x4F
89 #define CC2520_CMD_MEMCP                0x50
90 #define CC2520_CMD_MEMCPR               0x52
91 #define CC2520_CMD_MEMXCP               0x54
92 #define CC2520_CMD_MEMXWR               0x56
93 #define CC2520_CMD_BCLR                 0x58
94 #define CC2520_CMD_BSET                 0x59
95 #define CC2520_CMD_CTR_UCTR             0x60
96 #define CC2520_CMD_CBCMAC               0x64
97 #define CC2520_CMD_UCBCMAC              0x66
98 #define CC2520_CMD_CCM                  0x68
99 #define CC2520_CMD_UCCM                 0x6A
100 #define CC2520_CMD_ECB                  0x70
101 #define CC2520_CMD_ECBO                 0x72
102 #define CC2520_CMD_ECBX                 0x74
103 #define CC2520_CMD_INC                  0x78
104 #define CC2520_CMD_ABORT                0x7F
105 #define CC2520_CMD_REGISTER_READ        0x80
106 #define CC2520_CMD_REGISTER_WRITE       0xC0
107
108 /* status registers */
109 #define CC2520_CHIPID                   0x40
110 #define CC2520_VERSION                  0x42
111 #define CC2520_EXTCLOCK                 0x44
112 #define CC2520_MDMCTRL0                 0x46
113 #define CC2520_MDMCTRL1                 0x47
114 #define CC2520_FREQEST                  0x48
115 #define CC2520_RXCTRL                   0x4A
116 #define CC2520_FSCTRL                   0x4C
117 #define CC2520_FSCAL0                   0x4E
118 #define CC2520_FSCAL1                   0x4F
119 #define CC2520_FSCAL2                   0x50
120 #define CC2520_FSCAL3                   0x51
121 #define CC2520_AGCCTRL0                 0x52
122 #define CC2520_AGCCTRL1                 0x53
123 #define CC2520_AGCCTRL2                 0x54
124 #define CC2520_AGCCTRL3                 0x55
125 #define CC2520_ADCTEST0                 0x56
126 #define CC2520_ADCTEST1                 0x57
127 #define CC2520_ADCTEST2                 0x58
128 #define CC2520_MDMTEST0                 0x5A
129 #define CC2520_MDMTEST1                 0x5B
130 #define CC2520_DACTEST0                 0x5C
131 #define CC2520_DACTEST1                 0x5D
132 #define CC2520_ATEST                    0x5E
133 #define CC2520_DACTEST2                 0x5F
134 #define CC2520_PTEST0                   0x60
135 #define CC2520_PTEST1                   0x61
136 #define CC2520_RESERVED                 0x62
137 #define CC2520_DPUBIST                  0x7A
138 #define CC2520_ACTBIST                  0x7C
139 #define CC2520_RAMBIST                  0x7E
140
141 /* frame registers */
142 #define CC2520_FRMFILT0                 0x00
143 #define CC2520_FRMFILT1                 0x01
144 #define CC2520_SRCMATCH                 0x02
145 #define CC2520_SRCSHORTEN0              0x04
146 #define CC2520_SRCSHORTEN1              0x05
147 #define CC2520_SRCSHORTEN2              0x06
148 #define CC2520_SRCEXTEN0                0x08
149 #define CC2520_SRCEXTEN1                0x09
150 #define CC2520_SRCEXTEN2                0x0A
151 #define CC2520_FRMCTRL0                 0x0C
152 #define CC2520_FRMCTRL1                 0x0D
153 #define CC2520_RXENABLE0                0x0E
154 #define CC2520_RXENABLE1                0x0F
155 #define CC2520_EXCFLAG0                 0x10
156 #define CC2520_EXCFLAG1                 0x11
157 #define CC2520_EXCFLAG2                 0x12
158 #define CC2520_EXCMASKA0                0x14
159 #define CC2520_EXCMASKA1                0x15
160 #define CC2520_EXCMASKA2                0x16
161 #define CC2520_EXCMASKB0                0x18
162 #define CC2520_EXCMASKB1                0x19
163 #define CC2520_EXCMASKB2                0x1A
164 #define CC2520_EXCBINDX0                0x1C
165 #define CC2520_EXCBINDX1                0x1D
166 #define CC2520_EXCBINDY0                0x1E
167 #define CC2520_EXCBINDY1                0x1F
168 #define CC2520_GPIOCTRL0                0x20
169 #define CC2520_GPIOCTRL1                0x21
170 #define CC2520_GPIOCTRL2                0x22
171 #define CC2520_GPIOCTRL3                0x23
172 #define CC2520_GPIOCTRL4                0x24
173 #define CC2520_GPIOCTRL5                0x25
174 #define CC2520_GPIOPOLARITY             0x26
175 #define CC2520_GPIOCTRL                 0x28
176 #define CC2520_DPUCON                   0x2A
177 #define CC2520_DPUSTAT                  0x2C
178 #define CC2520_FREQCTRL                 0x2E
179 #define CC2520_FREQTUNE                 0x2F
180 #define CC2520_TXPOWER                  0x30
181 #define CC2520_TXCTRL                   0x31
182 #define CC2520_FSMSTAT0                 0x32
183 #define CC2520_FSMSTAT1                 0x33
184 #define CC2520_FIFOPCTRL                0x34
185 #define CC2520_FSMCTRL                  0x35
186 #define CC2520_CCACTRL0                 0x36
187 #define CC2520_CCACTRL1                 0x37
188 #define CC2520_RSSI                     0x38
189 #define CC2520_RSSISTAT                 0x39
190 #define CC2520_RXFIRST                  0x3C
191 #define CC2520_RXFIFOCNT                0x3E
192 #define CC2520_TXFIFOCNT                0x3F
193
194 /* CC2520_FRMFILT0 */
195 #define FRMFILT0_FRAME_FILTER_EN        BIT(0)
196 #define FRMFILT0_PAN_COORDINATOR        BIT(1)
197
198 /* CC2520_FRMCTRL0 */
199 #define FRMCTRL0_AUTOACK                BIT(5)
200 #define FRMCTRL0_AUTOCRC                BIT(6)
201
202 /* CC2520_FRMCTRL1 */
203 #define FRMCTRL1_SET_RXENMASK_ON_TX     BIT(0)
204 #define FRMCTRL1_IGNORE_TX_UNDERF       BIT(1)
205
206 /* Driver private information */
207 struct cc2520_private {
208         struct spi_device *spi;         /* SPI device structure */
209         struct ieee802154_hw *hw;       /* IEEE-802.15.4 device */
210         u8 *buf;                        /* SPI TX/Rx data buffer */
211         struct mutex buffer_mutex;      /* SPI buffer mutex */
212         bool is_tx;                     /* Flag for sync b/w Tx and Rx */
213         bool amplified;                 /* Flag for CC2591 */
214         int fifo_pin;                   /* FIFO GPIO pin number */
215         struct work_struct fifop_irqwork;/* Workqueue for FIFOP */
216         spinlock_t lock;                /* Lock for is_tx*/
217         struct completion tx_complete;  /* Work completion for Tx */
218         bool promiscuous;               /* Flag for promiscuous mode */
219 };
220
221 /* Generic Functions */
222 static int
223 cc2520_cmd_strobe(struct cc2520_private *priv, u8 cmd)
224 {
225         int ret;
226         u8 status = 0xff;
227         struct spi_message msg;
228         struct spi_transfer xfer = {
229                 .len = 0,
230                 .tx_buf = priv->buf,
231                 .rx_buf = priv->buf,
232         };
233
234         spi_message_init(&msg);
235         spi_message_add_tail(&xfer, &msg);
236
237         mutex_lock(&priv->buffer_mutex);
238         priv->buf[xfer.len++] = cmd;
239         dev_vdbg(&priv->spi->dev,
240                  "command strobe buf[0] = %02x\n",
241                  priv->buf[0]);
242
243         ret = spi_sync(priv->spi, &msg);
244         if (!ret)
245                 status = priv->buf[0];
246         dev_vdbg(&priv->spi->dev,
247                  "buf[0] = %02x\n", priv->buf[0]);
248         mutex_unlock(&priv->buffer_mutex);
249
250         return ret;
251 }
252
253 static int
254 cc2520_get_status(struct cc2520_private *priv, u8 *status)
255 {
256         int ret;
257         struct spi_message msg;
258         struct spi_transfer xfer = {
259                 .len = 0,
260                 .tx_buf = priv->buf,
261                 .rx_buf = priv->buf,
262         };
263
264         spi_message_init(&msg);
265         spi_message_add_tail(&xfer, &msg);
266
267         mutex_lock(&priv->buffer_mutex);
268         priv->buf[xfer.len++] = CC2520_CMD_SNOP;
269         dev_vdbg(&priv->spi->dev,
270                  "get status command buf[0] = %02x\n", priv->buf[0]);
271
272         ret = spi_sync(priv->spi, &msg);
273         if (!ret)
274                 *status = priv->buf[0];
275         dev_vdbg(&priv->spi->dev,
276                  "buf[0] = %02x\n", priv->buf[0]);
277         mutex_unlock(&priv->buffer_mutex);
278
279         return ret;
280 }
281
282 static int
283 cc2520_write_register(struct cc2520_private *priv, u8 reg, u8 value)
284 {
285         int status;
286         struct spi_message msg;
287         struct spi_transfer xfer = {
288                 .len = 0,
289                 .tx_buf = priv->buf,
290                 .rx_buf = priv->buf,
291         };
292
293         spi_message_init(&msg);
294         spi_message_add_tail(&xfer, &msg);
295
296         mutex_lock(&priv->buffer_mutex);
297
298         if (reg <= CC2520_FREG_MASK) {
299                 priv->buf[xfer.len++] = CC2520_CMD_REGISTER_WRITE | reg;
300                 priv->buf[xfer.len++] = value;
301         } else {
302                 priv->buf[xfer.len++] = CC2520_CMD_MEMORY_WRITE;
303                 priv->buf[xfer.len++] = reg;
304                 priv->buf[xfer.len++] = value;
305         }
306         status = spi_sync(priv->spi, &msg);
307         if (msg.status)
308                 status = msg.status;
309
310         mutex_unlock(&priv->buffer_mutex);
311
312         return status;
313 }
314
315 static int
316 cc2520_write_ram(struct cc2520_private *priv, u16 reg, u8 len, u8 *data)
317 {
318         int status;
319         struct spi_message msg;
320         struct spi_transfer xfer_head = {
321                 .len        = 0,
322                 .tx_buf        = priv->buf,
323                 .rx_buf        = priv->buf,
324         };
325
326         struct spi_transfer xfer_buf = {
327                 .len = len,
328                 .tx_buf = data,
329         };
330
331         mutex_lock(&priv->buffer_mutex);
332         priv->buf[xfer_head.len++] = (CC2520_CMD_MEMORY_WRITE |
333                                                 ((reg >> 8) & 0xff));
334         priv->buf[xfer_head.len++] = reg & 0xff;
335
336         spi_message_init(&msg);
337         spi_message_add_tail(&xfer_head, &msg);
338         spi_message_add_tail(&xfer_buf, &msg);
339
340         status = spi_sync(priv->spi, &msg);
341         dev_dbg(&priv->spi->dev, "spi status = %d\n", status);
342         if (msg.status)
343                 status = msg.status;
344
345         mutex_unlock(&priv->buffer_mutex);
346         return status;
347 }
348
349 static int
350 cc2520_read_register(struct cc2520_private *priv, u8 reg, u8 *data)
351 {
352         int status;
353         struct spi_message msg;
354         struct spi_transfer xfer1 = {
355                 .len = 0,
356                 .tx_buf = priv->buf,
357                 .rx_buf = priv->buf,
358         };
359
360         struct spi_transfer xfer2 = {
361                 .len = 1,
362                 .rx_buf = data,
363         };
364
365         spi_message_init(&msg);
366         spi_message_add_tail(&xfer1, &msg);
367         spi_message_add_tail(&xfer2, &msg);
368
369         mutex_lock(&priv->buffer_mutex);
370         priv->buf[xfer1.len++] = CC2520_CMD_MEMORY_READ;
371         priv->buf[xfer1.len++] = reg;
372
373         status = spi_sync(priv->spi, &msg);
374         dev_dbg(&priv->spi->dev,
375                 "spi status = %d\n", status);
376         if (msg.status)
377                 status = msg.status;
378
379         mutex_unlock(&priv->buffer_mutex);
380
381         return status;
382 }
383
384 static int
385 cc2520_write_txfifo(struct cc2520_private *priv, u8 pkt_len, u8 *data, u8 len)
386 {
387         int status;
388
389         /* length byte must include FCS even
390          * if it is calculated in the hardware
391          */
392         int len_byte = pkt_len;
393
394         struct spi_message msg;
395
396         struct spi_transfer xfer_head = {
397                 .len = 0,
398                 .tx_buf = priv->buf,
399                 .rx_buf = priv->buf,
400         };
401         struct spi_transfer xfer_len = {
402                 .len = 1,
403                 .tx_buf = &len_byte,
404         };
405         struct spi_transfer xfer_buf = {
406                 .len = len,
407                 .tx_buf = data,
408         };
409
410         spi_message_init(&msg);
411         spi_message_add_tail(&xfer_head, &msg);
412         spi_message_add_tail(&xfer_len, &msg);
413         spi_message_add_tail(&xfer_buf, &msg);
414
415         mutex_lock(&priv->buffer_mutex);
416         priv->buf[xfer_head.len++] = CC2520_CMD_TXBUF;
417         dev_vdbg(&priv->spi->dev,
418                  "TX_FIFO cmd buf[0] = %02x\n", priv->buf[0]);
419
420         status = spi_sync(priv->spi, &msg);
421         dev_vdbg(&priv->spi->dev, "status = %d\n", status);
422         if (msg.status)
423                 status = msg.status;
424         dev_vdbg(&priv->spi->dev, "status = %d\n", status);
425         dev_vdbg(&priv->spi->dev, "buf[0] = %02x\n", priv->buf[0]);
426         mutex_unlock(&priv->buffer_mutex);
427
428         return status;
429 }
430
431 static int
432 cc2520_read_rxfifo(struct cc2520_private *priv, u8 *data, u8 len)
433 {
434         int status;
435         struct spi_message msg;
436
437         struct spi_transfer xfer_head = {
438                 .len = 0,
439                 .tx_buf = priv->buf,
440                 .rx_buf = priv->buf,
441         };
442         struct spi_transfer xfer_buf = {
443                 .len = len,
444                 .rx_buf = data,
445         };
446
447         spi_message_init(&msg);
448         spi_message_add_tail(&xfer_head, &msg);
449         spi_message_add_tail(&xfer_buf, &msg);
450
451         mutex_lock(&priv->buffer_mutex);
452         priv->buf[xfer_head.len++] = CC2520_CMD_RXBUF;
453
454         dev_vdbg(&priv->spi->dev, "read rxfifo buf[0] = %02x\n", priv->buf[0]);
455         dev_vdbg(&priv->spi->dev, "buf[1] = %02x\n", priv->buf[1]);
456
457         status = spi_sync(priv->spi, &msg);
458         dev_vdbg(&priv->spi->dev, "status = %d\n", status);
459         if (msg.status)
460                 status = msg.status;
461         dev_vdbg(&priv->spi->dev, "status = %d\n", status);
462         dev_vdbg(&priv->spi->dev,
463                  "return status buf[0] = %02x\n", priv->buf[0]);
464         dev_vdbg(&priv->spi->dev, "length buf[1] = %02x\n", priv->buf[1]);
465
466         mutex_unlock(&priv->buffer_mutex);
467
468         return status;
469 }
470
471 static int cc2520_start(struct ieee802154_hw *hw)
472 {
473         return cc2520_cmd_strobe(hw->priv, CC2520_CMD_SRXON);
474 }
475
476 static void cc2520_stop(struct ieee802154_hw *hw)
477 {
478         cc2520_cmd_strobe(hw->priv, CC2520_CMD_SRFOFF);
479 }
480
481 static int
482 cc2520_tx(struct ieee802154_hw *hw, struct sk_buff *skb)
483 {
484         struct cc2520_private *priv = hw->priv;
485         unsigned long flags;
486         int rc;
487         u8 status = 0;
488         u8 pkt_len;
489
490         /* In promiscuous mode we disable AUTOCRC so we can get the raw CRC
491          * values on RX. This means we need to manually add the CRC on TX.
492          */
493         if (priv->promiscuous) {
494                 u16 crc = crc_ccitt(0, skb->data, skb->len);
495
496                 put_unaligned_le16(crc, skb_put(skb, 2));
497                 pkt_len = skb->len;
498         } else {
499                 pkt_len = skb->len + 2;
500         }
501
502         rc = cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHTX);
503         if (rc)
504                 goto err_tx;
505
506         rc = cc2520_write_txfifo(priv, pkt_len, skb->data, skb->len);
507         if (rc)
508                 goto err_tx;
509
510         rc = cc2520_get_status(priv, &status);
511         if (rc)
512                 goto err_tx;
513
514         if (status & CC2520_STATUS_TX_UNDERFLOW) {
515                 dev_err(&priv->spi->dev, "cc2520 tx underflow exception\n");
516                 goto err_tx;
517         }
518
519         spin_lock_irqsave(&priv->lock, flags);
520         BUG_ON(priv->is_tx);
521         priv->is_tx = 1;
522         spin_unlock_irqrestore(&priv->lock, flags);
523
524         rc = cc2520_cmd_strobe(priv, CC2520_CMD_STXONCCA);
525         if (rc)
526                 goto err;
527
528         rc = wait_for_completion_interruptible(&priv->tx_complete);
529         if (rc < 0)
530                 goto err;
531
532         cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHTX);
533         cc2520_cmd_strobe(priv, CC2520_CMD_SRXON);
534
535         return rc;
536 err:
537         spin_lock_irqsave(&priv->lock, flags);
538         priv->is_tx = 0;
539         spin_unlock_irqrestore(&priv->lock, flags);
540 err_tx:
541         return rc;
542 }
543
544 static int cc2520_rx(struct cc2520_private *priv)
545 {
546         u8 len = 0, lqi = 0, bytes = 1;
547         struct sk_buff *skb;
548
549         /* Read single length byte from the radio. */
550         cc2520_read_rxfifo(priv, &len, bytes);
551
552         if (!ieee802154_is_valid_psdu_len(len)) {
553                 /* Corrupted frame received, clear frame buffer by
554                  * reading entire buffer.
555                  */
556                 dev_dbg(&priv->spi->dev, "corrupted frame received\n");
557                 len = IEEE802154_MTU;
558         }
559
560         skb = dev_alloc_skb(len);
561         if (!skb)
562                 return -ENOMEM;
563
564         if (cc2520_read_rxfifo(priv, skb_put(skb, len), len)) {
565                 dev_dbg(&priv->spi->dev, "frame reception failed\n");
566                 kfree_skb(skb);
567                 return -EINVAL;
568         }
569
570         /* In promiscuous mode, we configure the radio to include the
571          * CRC (AUTOCRC==0) and we pass on the packet unconditionally. If not
572          * in promiscuous mode, we check the CRC here, but leave the
573          * RSSI/LQI/CRC_OK bytes as they will get removed in the mac layer.
574          */
575         if (!priv->promiscuous) {
576                 bool crc_ok;
577
578                 /* Check if the CRC is valid. With AUTOCRC set, the most
579                  * significant bit of the last byte returned from the CC2520
580                  * is CRC_OK flag. See section 20.3.4 of the datasheet.
581                  */
582                 crc_ok = skb->data[len - 1] & BIT(7);
583
584                 /* If we failed CRC drop the packet in the driver layer. */
585                 if (!crc_ok) {
586                         dev_dbg(&priv->spi->dev, "CRC check failed\n");
587                         kfree_skb(skb);
588                         return -EINVAL;
589                 }
590
591                 /* To calculate LQI, the lower 7 bits of the last byte (the
592                  * correlation value provided by the radio) must be scaled to
593                  * the range 0-255. According to section 20.6, the correlation
594                  * value ranges from 50-110. Ideally this would be calibrated
595                  * per hardware design, but we use roughly the datasheet values
596                  * to get close enough while avoiding floating point.
597                  */
598                 lqi = skb->data[len - 1] & 0x7f;
599                 if (lqi < 50)
600                         lqi = 50;
601                 else if (lqi > 113)
602                         lqi = 113;
603                 lqi = (lqi - 50) * 4;
604         }
605
606         ieee802154_rx_irqsafe(priv->hw, skb, lqi);
607
608         dev_vdbg(&priv->spi->dev, "RXFIFO: %x %x\n", len, lqi);
609
610         return 0;
611 }
612
613 static int
614 cc2520_ed(struct ieee802154_hw *hw, u8 *level)
615 {
616         struct cc2520_private *priv = hw->priv;
617         u8 status = 0xff;
618         u8 rssi;
619         int ret;
620
621         ret = cc2520_read_register(priv, CC2520_RSSISTAT, &status);
622         if (ret)
623                 return ret;
624
625         if (status != RSSI_VALID)
626                 return -EINVAL;
627
628         ret = cc2520_read_register(priv, CC2520_RSSI, &rssi);
629         if (ret)
630                 return ret;
631
632         /* level = RSSI(rssi) - OFFSET [dBm] : offset is 76dBm */
633         *level = rssi - RSSI_OFFSET;
634
635         return 0;
636 }
637
638 static int
639 cc2520_set_channel(struct ieee802154_hw *hw, u8 page, u8 channel)
640 {
641         struct cc2520_private *priv = hw->priv;
642         int ret;
643
644         dev_dbg(&priv->spi->dev, "trying to set channel\n");
645
646         BUG_ON(page != 0);
647         BUG_ON(channel < CC2520_MINCHANNEL);
648         BUG_ON(channel > CC2520_MAXCHANNEL);
649
650         ret = cc2520_write_register(priv, CC2520_FREQCTRL,
651                                     11 + 5*(channel - 11));
652
653         return ret;
654 }
655
656 static int
657 cc2520_filter(struct ieee802154_hw *hw,
658               struct ieee802154_hw_addr_filt *filt, unsigned long changed)
659 {
660         struct cc2520_private *priv = hw->priv;
661         int ret = 0;
662
663         if (changed & IEEE802154_AFILT_PANID_CHANGED) {
664                 u16 panid = le16_to_cpu(filt->pan_id);
665
666                 dev_vdbg(&priv->spi->dev,
667                          "cc2520_filter called for pan id\n");
668                 ret = cc2520_write_ram(priv, CC2520RAM_PANID,
669                                        sizeof(panid), (u8 *)&panid);
670         }
671
672         if (changed & IEEE802154_AFILT_IEEEADDR_CHANGED) {
673                 dev_vdbg(&priv->spi->dev,
674                          "cc2520_filter called for IEEE addr\n");
675                 ret = cc2520_write_ram(priv, CC2520RAM_IEEEADDR,
676                                        sizeof(filt->ieee_addr),
677                                        (u8 *)&filt->ieee_addr);
678         }
679
680         if (changed & IEEE802154_AFILT_SADDR_CHANGED) {
681                 u16 addr = le16_to_cpu(filt->short_addr);
682
683                 dev_vdbg(&priv->spi->dev,
684                          "cc2520_filter called for saddr\n");
685                 ret = cc2520_write_ram(priv, CC2520RAM_SHORTADDR,
686                                        sizeof(addr), (u8 *)&addr);
687         }
688
689         if (changed & IEEE802154_AFILT_PANC_CHANGED) {
690                 u8 frmfilt0;
691
692                 dev_vdbg(&priv->spi->dev,
693                          "cc2520_filter called for panc change\n");
694
695                 cc2520_read_register(priv, CC2520_FRMFILT0, &frmfilt0);
696
697                 if (filt->pan_coord)
698                         frmfilt0 |= FRMFILT0_PAN_COORDINATOR;
699                 else
700                         frmfilt0 &= ~FRMFILT0_PAN_COORDINATOR;
701
702                 ret = cc2520_write_register(priv, CC2520_FRMFILT0, frmfilt0);
703         }
704
705         return ret;
706 }
707
708 static inline int cc2520_set_tx_power(struct cc2520_private *priv, s32 mbm)
709 {
710         u8 power;
711
712         switch (mbm) {
713         case 500:
714                 power = 0xF7;
715                 break;
716         case 300:
717                 power = 0xF2;
718                 break;
719         case 200:
720                 power = 0xAB;
721                 break;
722         case 100:
723                 power = 0x13;
724                 break;
725         case 0:
726                 power = 0x32;
727                 break;
728         case -200:
729                 power = 0x81;
730                 break;
731         case -400:
732                 power = 0x88;
733                 break;
734         case -700:
735                 power = 0x2C;
736                 break;
737         case -1800:
738                 power = 0x03;
739                 break;
740         default:
741                 return -EINVAL;
742         }
743
744         return cc2520_write_register(priv, CC2520_TXPOWER, power);
745 }
746
747 static inline int cc2520_cc2591_set_tx_power(struct cc2520_private *priv,
748                                              s32 mbm)
749 {
750         u8 power;
751
752         switch (mbm) {
753         case 1700:
754                 power = 0xF9;
755                 break;
756         case 1600:
757                 power = 0xF0;
758                 break;
759         case 1400:
760                 power = 0xA0;
761                 break;
762         case 1100:
763                 power = 0x2C;
764                 break;
765         case -100:
766                 power = 0x03;
767                 break;
768         case -800:
769                 power = 0x01;
770                 break;
771         default:
772                 return -EINVAL;
773         }
774
775         return cc2520_write_register(priv, CC2520_TXPOWER, power);
776 }
777
778 #define CC2520_MAX_TX_POWERS 0x8
779 static const s32 cc2520_powers[CC2520_MAX_TX_POWERS + 1] = {
780         500, 300, 200, 100, 0, -200, -400, -700, -1800,
781 };
782
783 #define CC2520_CC2591_MAX_TX_POWERS 0x5
784 static const s32 cc2520_cc2591_powers[CC2520_CC2591_MAX_TX_POWERS + 1] = {
785         1700, 1600, 1400, 1100, -100, -800,
786 };
787
788 static int
789 cc2520_set_txpower(struct ieee802154_hw *hw, s32 mbm)
790 {
791         struct cc2520_private *priv = hw->priv;
792
793         if (!priv->amplified)
794                 return cc2520_set_tx_power(priv, mbm);
795
796         return cc2520_cc2591_set_tx_power(priv, mbm);
797 }
798
799 static int
800 cc2520_set_promiscuous_mode(struct ieee802154_hw *hw, bool on)
801 {
802         struct cc2520_private *priv = hw->priv;
803         u8 frmfilt0;
804
805         dev_dbg(&priv->spi->dev, "%s : mode %d\n", __func__, on);
806
807         priv->promiscuous = on;
808
809         cc2520_read_register(priv, CC2520_FRMFILT0, &frmfilt0);
810
811         if (on) {
812                 /* Disable automatic ACK, automatic CRC, and frame filtering. */
813                 cc2520_write_register(priv, CC2520_FRMCTRL0, 0);
814                 frmfilt0 &= ~FRMFILT0_FRAME_FILTER_EN;
815         } else {
816                 cc2520_write_register(priv, CC2520_FRMCTRL0, FRMCTRL0_AUTOACK |
817                                                              FRMCTRL0_AUTOCRC);
818                 frmfilt0 |= FRMFILT0_FRAME_FILTER_EN;
819         }
820         return cc2520_write_register(priv, CC2520_FRMFILT0, frmfilt0);
821 }
822
823 static const struct ieee802154_ops cc2520_ops = {
824         .owner = THIS_MODULE,
825         .start = cc2520_start,
826         .stop = cc2520_stop,
827         .xmit_sync = cc2520_tx,
828         .ed = cc2520_ed,
829         .set_channel = cc2520_set_channel,
830         .set_hw_addr_filt = cc2520_filter,
831         .set_txpower = cc2520_set_txpower,
832         .set_promiscuous_mode = cc2520_set_promiscuous_mode,
833 };
834
835 static int cc2520_register(struct cc2520_private *priv)
836 {
837         int ret = -ENOMEM;
838
839         priv->hw = ieee802154_alloc_hw(sizeof(*priv), &cc2520_ops);
840         if (!priv->hw)
841                 goto err_ret;
842
843         priv->hw->priv = priv;
844         priv->hw->parent = &priv->spi->dev;
845         priv->hw->extra_tx_headroom = 0;
846         ieee802154_random_extended_addr(&priv->hw->phy->perm_extended_addr);
847
848         /* We do support only 2.4 Ghz */
849         priv->hw->phy->supported.channels[0] = 0x7FFF800;
850         priv->hw->flags = IEEE802154_HW_TX_OMIT_CKSUM | IEEE802154_HW_AFILT |
851                           IEEE802154_HW_PROMISCUOUS;
852
853         priv->hw->phy->flags = WPAN_PHY_FLAG_TXPOWER;
854
855         if (!priv->amplified) {
856                 priv->hw->phy->supported.tx_powers = cc2520_powers;
857                 priv->hw->phy->supported.tx_powers_size = ARRAY_SIZE(cc2520_powers);
858                 priv->hw->phy->transmit_power = priv->hw->phy->supported.tx_powers[4];
859         } else {
860                 priv->hw->phy->supported.tx_powers = cc2520_cc2591_powers;
861                 priv->hw->phy->supported.tx_powers_size = ARRAY_SIZE(cc2520_cc2591_powers);
862                 priv->hw->phy->transmit_power = priv->hw->phy->supported.tx_powers[0];
863         }
864
865         priv->hw->phy->current_channel = 11;
866
867         dev_vdbg(&priv->spi->dev, "registered cc2520\n");
868         ret = ieee802154_register_hw(priv->hw);
869         if (ret)
870                 goto err_free_device;
871
872         return 0;
873
874 err_free_device:
875         ieee802154_free_hw(priv->hw);
876 err_ret:
877         return ret;
878 }
879
880 static void cc2520_fifop_irqwork(struct work_struct *work)
881 {
882         struct cc2520_private *priv
883                 = container_of(work, struct cc2520_private, fifop_irqwork);
884
885         dev_dbg(&priv->spi->dev, "fifop interrupt received\n");
886
887         if (gpio_get_value(priv->fifo_pin))
888                 cc2520_rx(priv);
889         else
890                 dev_dbg(&priv->spi->dev, "rxfifo overflow\n");
891
892         cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHRX);
893         cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHRX);
894 }
895
896 static irqreturn_t cc2520_fifop_isr(int irq, void *data)
897 {
898         struct cc2520_private *priv = data;
899
900         schedule_work(&priv->fifop_irqwork);
901
902         return IRQ_HANDLED;
903 }
904
905 static irqreturn_t cc2520_sfd_isr(int irq, void *data)
906 {
907         struct cc2520_private *priv = data;
908         unsigned long flags;
909
910         spin_lock_irqsave(&priv->lock, flags);
911         if (priv->is_tx) {
912                 priv->is_tx = 0;
913                 spin_unlock_irqrestore(&priv->lock, flags);
914                 dev_dbg(&priv->spi->dev, "SFD for TX\n");
915                 complete(&priv->tx_complete);
916         } else {
917                 spin_unlock_irqrestore(&priv->lock, flags);
918                 dev_dbg(&priv->spi->dev, "SFD for RX\n");
919         }
920
921         return IRQ_HANDLED;
922 }
923
924 static int cc2520_get_platform_data(struct spi_device *spi,
925                                     struct cc2520_platform_data *pdata)
926 {
927         struct device_node *np = spi->dev.of_node;
928         struct cc2520_private *priv = spi_get_drvdata(spi);
929
930         if (!np) {
931                 struct cc2520_platform_data *spi_pdata = spi->dev.platform_data;
932                 if (!spi_pdata)
933                         return -ENOENT;
934                 *pdata = *spi_pdata;
935                 priv->fifo_pin = pdata->fifo;
936                 return 0;
937         }
938
939         pdata->fifo = of_get_named_gpio(np, "fifo-gpio", 0);
940         priv->fifo_pin = pdata->fifo;
941
942         pdata->fifop = of_get_named_gpio(np, "fifop-gpio", 0);
943
944         pdata->sfd = of_get_named_gpio(np, "sfd-gpio", 0);
945         pdata->cca = of_get_named_gpio(np, "cca-gpio", 0);
946         pdata->vreg = of_get_named_gpio(np, "vreg-gpio", 0);
947         pdata->reset = of_get_named_gpio(np, "reset-gpio", 0);
948
949         /* CC2591 front end for CC2520 */
950         if (of_property_read_bool(np, "amplified"))
951                 priv->amplified = true;
952
953         return 0;
954 }
955
956 static int cc2520_hw_init(struct cc2520_private *priv)
957 {
958         u8 status = 0, state = 0xff;
959         int ret;
960         int timeout = 100;
961         struct cc2520_platform_data pdata;
962
963         ret = cc2520_get_platform_data(priv->spi, &pdata);
964         if (ret)
965                 goto err_ret;
966
967         ret = cc2520_read_register(priv, CC2520_FSMSTAT1, &state);
968         if (ret)
969                 goto err_ret;
970
971         if (state != STATE_IDLE)
972                 return -EINVAL;
973
974         do {
975                 ret = cc2520_get_status(priv, &status);
976                 if (ret)
977                         goto err_ret;
978
979                 if (timeout-- <= 0) {
980                         dev_err(&priv->spi->dev, "oscillator start failed!\n");
981                         return ret;
982                 }
983                 udelay(1);
984         } while (!(status & CC2520_STATUS_XOSC32M_STABLE));
985
986         dev_vdbg(&priv->spi->dev, "oscillator brought up\n");
987
988         /* If the CC2520 is connected to a CC2591 amplifier, we must both
989          * configure GPIOs on the CC2520 to correctly configure the CC2591
990          * and change a couple settings of the CC2520 to work with the
991          * amplifier. See section 8 page 17 of TI application note AN065.
992          * http://www.ti.com/lit/an/swra229a/swra229a.pdf
993          */
994         if (priv->amplified) {
995                 ret = cc2520_write_register(priv, CC2520_AGCCTRL1, 0x16);
996                 if (ret)
997                         goto err_ret;
998
999                 ret = cc2520_write_register(priv, CC2520_GPIOCTRL0, 0x46);
1000                 if (ret)
1001                         goto err_ret;
1002
1003                 ret = cc2520_write_register(priv, CC2520_GPIOCTRL5, 0x47);
1004                 if (ret)
1005                         goto err_ret;
1006
1007                 ret = cc2520_write_register(priv, CC2520_GPIOPOLARITY, 0x1e);
1008                 if (ret)
1009                         goto err_ret;
1010
1011                 ret = cc2520_write_register(priv, CC2520_TXCTRL, 0xc1);
1012                 if (ret)
1013                         goto err_ret;
1014         } else {
1015                 ret = cc2520_write_register(priv, CC2520_AGCCTRL1, 0x11);
1016                 if (ret)
1017                         goto err_ret;
1018         }
1019
1020         /* Registers default value: section 28.1 in Datasheet */
1021
1022         /* Set the CCA threshold to -50 dBm. This seems to have been copied
1023          * from the TinyOS CC2520 driver and is much higher than the -84 dBm
1024          * threshold suggested in the datasheet.
1025          */
1026         ret = cc2520_write_register(priv, CC2520_CCACTRL0, 0x1A);
1027         if (ret)
1028                 goto err_ret;
1029
1030         ret = cc2520_write_register(priv, CC2520_MDMCTRL0, 0x85);
1031         if (ret)
1032                 goto err_ret;
1033
1034         ret = cc2520_write_register(priv, CC2520_MDMCTRL1, 0x14);
1035         if (ret)
1036                 goto err_ret;
1037
1038         ret = cc2520_write_register(priv, CC2520_RXCTRL, 0x3f);
1039         if (ret)
1040                 goto err_ret;
1041
1042         ret = cc2520_write_register(priv, CC2520_FSCTRL, 0x5a);
1043         if (ret)
1044                 goto err_ret;
1045
1046         ret = cc2520_write_register(priv, CC2520_FSCAL1, 0x2b);
1047         if (ret)
1048                 goto err_ret;
1049
1050         ret = cc2520_write_register(priv, CC2520_ADCTEST0, 0x10);
1051         if (ret)
1052                 goto err_ret;
1053
1054         ret = cc2520_write_register(priv, CC2520_ADCTEST1, 0x0e);
1055         if (ret)
1056                 goto err_ret;
1057
1058         ret = cc2520_write_register(priv, CC2520_ADCTEST2, 0x03);
1059         if (ret)
1060                 goto err_ret;
1061
1062         /* Configure registers correctly for this driver. */
1063         ret = cc2520_write_register(priv, CC2520_FRMCTRL1,
1064                                     FRMCTRL1_SET_RXENMASK_ON_TX |
1065                                     FRMCTRL1_IGNORE_TX_UNDERF);
1066         if (ret)
1067                 goto err_ret;
1068
1069         ret = cc2520_write_register(priv, CC2520_FIFOPCTRL, 127);
1070         if (ret)
1071                 goto err_ret;
1072
1073         return 0;
1074
1075 err_ret:
1076         return ret;
1077 }
1078
1079 static int cc2520_probe(struct spi_device *spi)
1080 {
1081         struct cc2520_private *priv;
1082         struct cc2520_platform_data pdata;
1083         int ret;
1084
1085         priv = devm_kzalloc(&spi->dev, sizeof(*priv), GFP_KERNEL);
1086         if (!priv)
1087                 return -ENOMEM;
1088
1089         spi_set_drvdata(spi, priv);
1090
1091         ret = cc2520_get_platform_data(spi, &pdata);
1092         if (ret < 0) {
1093                 dev_err(&spi->dev, "no platform data\n");
1094                 return -EINVAL;
1095         }
1096
1097         priv->spi = spi;
1098
1099         priv->buf = devm_kzalloc(&spi->dev,
1100                                  SPI_COMMAND_BUFFER, GFP_KERNEL);
1101         if (!priv->buf)
1102                 return -ENOMEM;
1103
1104         mutex_init(&priv->buffer_mutex);
1105         INIT_WORK(&priv->fifop_irqwork, cc2520_fifop_irqwork);
1106         spin_lock_init(&priv->lock);
1107         init_completion(&priv->tx_complete);
1108
1109         /* Assumption that CC2591 is not connected */
1110         priv->amplified = false;
1111
1112         /* Request all the gpio's */
1113         if (!gpio_is_valid(pdata.fifo)) {
1114                 dev_err(&spi->dev, "fifo gpio is not valid\n");
1115                 ret = -EINVAL;
1116                 goto err_hw_init;
1117         }
1118
1119         ret = devm_gpio_request_one(&spi->dev, pdata.fifo,
1120                                     GPIOF_IN, "fifo");
1121         if (ret)
1122                 goto err_hw_init;
1123
1124         if (!gpio_is_valid(pdata.cca)) {
1125                 dev_err(&spi->dev, "cca gpio is not valid\n");
1126                 ret = -EINVAL;
1127                 goto err_hw_init;
1128         }
1129
1130         ret = devm_gpio_request_one(&spi->dev, pdata.cca,
1131                                     GPIOF_IN, "cca");
1132         if (ret)
1133                 goto err_hw_init;
1134
1135         if (!gpio_is_valid(pdata.fifop)) {
1136                 dev_err(&spi->dev, "fifop gpio is not valid\n");
1137                 ret = -EINVAL;
1138                 goto err_hw_init;
1139         }
1140
1141         ret = devm_gpio_request_one(&spi->dev, pdata.fifop,
1142                                     GPIOF_IN, "fifop");
1143         if (ret)
1144                 goto err_hw_init;
1145
1146         if (!gpio_is_valid(pdata.sfd)) {
1147                 dev_err(&spi->dev, "sfd gpio is not valid\n");
1148                 ret = -EINVAL;
1149                 goto err_hw_init;
1150         }
1151
1152         ret = devm_gpio_request_one(&spi->dev, pdata.sfd,
1153                                     GPIOF_IN, "sfd");
1154         if (ret)
1155                 goto err_hw_init;
1156
1157         if (!gpio_is_valid(pdata.reset)) {
1158                 dev_err(&spi->dev, "reset gpio is not valid\n");
1159                 ret = -EINVAL;
1160                 goto err_hw_init;
1161         }
1162
1163         ret = devm_gpio_request_one(&spi->dev, pdata.reset,
1164                                     GPIOF_OUT_INIT_LOW, "reset");
1165         if (ret)
1166                 goto err_hw_init;
1167
1168         if (!gpio_is_valid(pdata.vreg)) {
1169                 dev_err(&spi->dev, "vreg gpio is not valid\n");
1170                 ret = -EINVAL;
1171                 goto err_hw_init;
1172         }
1173
1174         ret = devm_gpio_request_one(&spi->dev, pdata.vreg,
1175                                     GPIOF_OUT_INIT_LOW, "vreg");
1176         if (ret)
1177                 goto err_hw_init;
1178
1179         gpio_set_value(pdata.vreg, HIGH);
1180         usleep_range(100, 150);
1181
1182         gpio_set_value(pdata.reset, HIGH);
1183         usleep_range(200, 250);
1184
1185         ret = cc2520_hw_init(priv);
1186         if (ret)
1187                 goto err_hw_init;
1188
1189         /* Set up fifop interrupt */
1190         ret = devm_request_irq(&spi->dev,
1191                                gpio_to_irq(pdata.fifop),
1192                                cc2520_fifop_isr,
1193                                IRQF_TRIGGER_RISING,
1194                                dev_name(&spi->dev),
1195                                priv);
1196         if (ret) {
1197                 dev_err(&spi->dev, "could not get fifop irq\n");
1198                 goto err_hw_init;
1199         }
1200
1201         /* Set up sfd interrupt */
1202         ret = devm_request_irq(&spi->dev,
1203                                gpio_to_irq(pdata.sfd),
1204                                cc2520_sfd_isr,
1205                                IRQF_TRIGGER_FALLING,
1206                                dev_name(&spi->dev),
1207                                priv);
1208         if (ret) {
1209                 dev_err(&spi->dev, "could not get sfd irq\n");
1210                 goto err_hw_init;
1211         }
1212
1213         ret = cc2520_register(priv);
1214         if (ret)
1215                 goto err_hw_init;
1216
1217         return 0;
1218
1219 err_hw_init:
1220         mutex_destroy(&priv->buffer_mutex);
1221         flush_work(&priv->fifop_irqwork);
1222         return ret;
1223 }
1224
1225 static int cc2520_remove(struct spi_device *spi)
1226 {
1227         struct cc2520_private *priv = spi_get_drvdata(spi);
1228
1229         mutex_destroy(&priv->buffer_mutex);
1230         flush_work(&priv->fifop_irqwork);
1231
1232         ieee802154_unregister_hw(priv->hw);
1233         ieee802154_free_hw(priv->hw);
1234
1235         return 0;
1236 }
1237
1238 static const struct spi_device_id cc2520_ids[] = {
1239         {"cc2520", },
1240         {},
1241 };
1242 MODULE_DEVICE_TABLE(spi, cc2520_ids);
1243
1244 static const struct of_device_id cc2520_of_ids[] = {
1245         {.compatible = "ti,cc2520", },
1246         {},
1247 };
1248 MODULE_DEVICE_TABLE(of, cc2520_of_ids);
1249
1250 /* SPI driver structure */
1251 static struct spi_driver cc2520_driver = {
1252         .driver = {
1253                 .name = "cc2520",
1254                 .of_match_table = of_match_ptr(cc2520_of_ids),
1255         },
1256         .id_table = cc2520_ids,
1257         .probe = cc2520_probe,
1258         .remove = cc2520_remove,
1259 };
1260 module_spi_driver(cc2520_driver);
1261
1262 MODULE_AUTHOR("Varka Bhadram <varkab@cdac.in>");
1263 MODULE_DESCRIPTION("CC2520 Transceiver Driver");
1264 MODULE_LICENSE("GPL v2");