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 <asm/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 */
201struct 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 */
216static int
217cc2520_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
244static int
245cc2520_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
273static int
274cc2520_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
306static int
307cc2520_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
340static int
341cc2520_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
375static int
376cc2520_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
422static int
423cc2520_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
462static int cc2520_start(struct ieee802154_hw *hw)
463{
464	return cc2520_cmd_strobe(hw->priv, CC2520_CMD_SRXON);
465}
466
467static void cc2520_stop(struct ieee802154_hw *hw)
468{
469	cc2520_cmd_strobe(hw->priv, CC2520_CMD_SRFOFF);
470}
471
472static int
473cc2520_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;
528err:
529	spin_lock_irqsave(&priv->lock, flags);
530	priv->is_tx = 0;
531	spin_unlock_irqrestore(&priv->lock, flags);
532err_tx:
533	return rc;
534}
535
536static 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
605static int
606cc2520_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
630static int
631cc2520_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
648static int
649cc2520_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
698static 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
737static 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
769static 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
774static const s32 cc2520_cc2591_powers[CC2520_CC2591_MAX_TX_POWERS + 1] = {
775	1700, 1600, 1400, 1100, -100, -800,
776};
777
778static int
779cc2520_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
789static int
790cc2520_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
813static 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
825static 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
864err_free_device:
865	ieee802154_free_hw(priv->hw);
866err_ret:
867	return ret;
868}
869
870static 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
886static 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
895static 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
914static 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
1028err_ret:
1029	return ret;
1030}
1031
1032static 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
1149err_hw_init:
1150	mutex_destroy(&priv->buffer_mutex);
1151	flush_work(&priv->fifop_irqwork);
1152	return ret;
1153}
1154
1155static 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
1166static const struct spi_device_id cc2520_ids[] = {
1167	{"cc2520", },
1168	{},
1169};
1170MODULE_DEVICE_TABLE(spi, cc2520_ids);
1171
1172static const struct of_device_id cc2520_of_ids[] = {
1173	{.compatible = "ti,cc2520", },
1174	{},
1175};
1176MODULE_DEVICE_TABLE(of, cc2520_of_ids);
1177
1178/* SPI driver structure */
1179static 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};
1188module_spi_driver(cc2520_driver);
1189
1190MODULE_AUTHOR("Varka Bhadram <varkab@cdac.in>");
1191MODULE_DESCRIPTION("CC2520 Transceiver Driver");
1192MODULE_LICENSE("GPL v2");
1193