1// SPDX-License-Identifier: GPL-2.0-or-later
2/* Driver for TI CC2520 802.15.4 Wireless-PAN Networking controller
3 *
4 * Copyright (C) 2014 Varka Bhadram <varkab@cdac.in>
5 *		      Md.Jamal Mohiuddin <mjmohiuddin@cdac.in>
6 *		      P Sowjanya <sowjanyap@cdac.in>
7 */
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/gpio.h>
11#include <linux/delay.h>
12#include <linux/spi/spi.h>
13#include <linux/spi/cc2520.h>
14#include <linux/workqueue.h>
15#include <linux/interrupt.h>
16#include <linux/skbuff.h>
17#include <linux/of_gpio.h>
18#include <linux/ieee802154.h>
19#include <linux/crc-ccitt.h>
20#include <asm/unaligned.h>
21
22#include <net/mac802154.h>
23#include <net/cfg802154.h>
24
25#define	SPI_COMMAND_BUFFER	3
26#define	HIGH			1
27#define	LOW			0
28#define	STATE_IDLE		0
29#define	RSSI_VALID		0
30#define	RSSI_OFFSET		78
31
32#define	CC2520_RAM_SIZE		640
33#define	CC2520_FIFO_SIZE	128
34
35#define	CC2520RAM_TXFIFO	0x100
36#define	CC2520RAM_RXFIFO	0x180
37#define	CC2520RAM_IEEEADDR	0x3EA
38#define	CC2520RAM_PANID		0x3F2
39#define	CC2520RAM_SHORTADDR	0x3F4
40
41#define	CC2520_FREG_MASK	0x3F
42
43/* status byte values */
44#define	CC2520_STATUS_XOSC32M_STABLE	BIT(7)
45#define	CC2520_STATUS_RSSI_VALID	BIT(6)
46#define	CC2520_STATUS_TX_UNDERFLOW	BIT(3)
47
48/* IEEE-802.15.4 defined constants (2.4 GHz logical channels) */
49#define	CC2520_MINCHANNEL		11
50#define	CC2520_MAXCHANNEL		26
51#define	CC2520_CHANNEL_SPACING		5
52
53/* command strobes */
54#define	CC2520_CMD_SNOP			0x00
55#define	CC2520_CMD_IBUFLD		0x02
56#define	CC2520_CMD_SIBUFEX		0x03
57#define	CC2520_CMD_SSAMPLECCA		0x04
58#define	CC2520_CMD_SRES			0x0f
59#define	CC2520_CMD_MEMORY_MASK		0x0f
60#define	CC2520_CMD_MEMORY_READ		0x10
61#define	CC2520_CMD_MEMORY_WRITE		0x20
62#define	CC2520_CMD_RXBUF		0x30
63#define	CC2520_CMD_RXBUFCP		0x38
64#define	CC2520_CMD_RXBUFMOV		0x32
65#define	CC2520_CMD_TXBUF		0x3A
66#define	CC2520_CMD_TXBUFCP		0x3E
67#define	CC2520_CMD_RANDOM		0x3C
68#define	CC2520_CMD_SXOSCON		0x40
69#define	CC2520_CMD_STXCAL		0x41
70#define	CC2520_CMD_SRXON		0x42
71#define	CC2520_CMD_STXON		0x43
72#define	CC2520_CMD_STXONCCA		0x44
73#define	CC2520_CMD_SRFOFF		0x45
74#define	CC2520_CMD_SXOSCOFF		0x46
75#define	CC2520_CMD_SFLUSHRX		0x47
76#define	CC2520_CMD_SFLUSHTX		0x48
77#define	CC2520_CMD_SACK			0x49
78#define	CC2520_CMD_SACKPEND		0x4A
79#define	CC2520_CMD_SNACK		0x4B
80#define	CC2520_CMD_SRXMASKBITSET	0x4C
81#define	CC2520_CMD_SRXMASKBITCLR	0x4D
82#define	CC2520_CMD_RXMASKAND		0x4E
83#define	CC2520_CMD_RXMASKOR		0x4F
84#define	CC2520_CMD_MEMCP		0x50
85#define	CC2520_CMD_MEMCPR		0x52
86#define	CC2520_CMD_MEMXCP		0x54
87#define	CC2520_CMD_MEMXWR		0x56
88#define	CC2520_CMD_BCLR			0x58
89#define	CC2520_CMD_BSET			0x59
90#define	CC2520_CMD_CTR_UCTR		0x60
91#define	CC2520_CMD_CBCMAC		0x64
92#define	CC2520_CMD_UCBCMAC		0x66
93#define	CC2520_CMD_CCM			0x68
94#define	CC2520_CMD_UCCM			0x6A
95#define	CC2520_CMD_ECB			0x70
96#define	CC2520_CMD_ECBO			0x72
97#define	CC2520_CMD_ECBX			0x74
98#define	CC2520_CMD_INC			0x78
99#define	CC2520_CMD_ABORT		0x7F
100#define	CC2520_CMD_REGISTER_READ	0x80
101#define	CC2520_CMD_REGISTER_WRITE	0xC0
102
103/* status registers */
104#define	CC2520_CHIPID			0x40
105#define	CC2520_VERSION			0x42
106#define	CC2520_EXTCLOCK			0x44
107#define	CC2520_MDMCTRL0			0x46
108#define	CC2520_MDMCTRL1			0x47
109#define	CC2520_FREQEST			0x48
110#define	CC2520_RXCTRL			0x4A
111#define	CC2520_FSCTRL			0x4C
112#define	CC2520_FSCAL0			0x4E
113#define	CC2520_FSCAL1			0x4F
114#define	CC2520_FSCAL2			0x50
115#define	CC2520_FSCAL3			0x51
116#define	CC2520_AGCCTRL0			0x52
117#define	CC2520_AGCCTRL1			0x53
118#define	CC2520_AGCCTRL2			0x54
119#define	CC2520_AGCCTRL3			0x55
120#define	CC2520_ADCTEST0			0x56
121#define	CC2520_ADCTEST1			0x57
122#define	CC2520_ADCTEST2			0x58
123#define	CC2520_MDMTEST0			0x5A
124#define	CC2520_MDMTEST1			0x5B
125#define	CC2520_DACTEST0			0x5C
126#define	CC2520_DACTEST1			0x5D
127#define	CC2520_ATEST			0x5E
128#define	CC2520_DACTEST2			0x5F
129#define	CC2520_PTEST0			0x60
130#define	CC2520_PTEST1			0x61
131#define	CC2520_RESERVED			0x62
132#define	CC2520_DPUBIST			0x7A
133#define	CC2520_ACTBIST			0x7C
134#define	CC2520_RAMBIST			0x7E
135
136/* frame registers */
137#define	CC2520_FRMFILT0			0x00
138#define	CC2520_FRMFILT1			0x01
139#define	CC2520_SRCMATCH			0x02
140#define	CC2520_SRCSHORTEN0		0x04
141#define	CC2520_SRCSHORTEN1		0x05
142#define	CC2520_SRCSHORTEN2		0x06
143#define	CC2520_SRCEXTEN0		0x08
144#define	CC2520_SRCEXTEN1		0x09
145#define	CC2520_SRCEXTEN2		0x0A
146#define	CC2520_FRMCTRL0			0x0C
147#define	CC2520_FRMCTRL1			0x0D
148#define	CC2520_RXENABLE0		0x0E
149#define	CC2520_RXENABLE1		0x0F
150#define	CC2520_EXCFLAG0			0x10
151#define	CC2520_EXCFLAG1			0x11
152#define	CC2520_EXCFLAG2			0x12
153#define	CC2520_EXCMASKA0		0x14
154#define	CC2520_EXCMASKA1		0x15
155#define	CC2520_EXCMASKA2		0x16
156#define	CC2520_EXCMASKB0		0x18
157#define	CC2520_EXCMASKB1		0x19
158#define	CC2520_EXCMASKB2		0x1A
159#define	CC2520_EXCBINDX0		0x1C
160#define	CC2520_EXCBINDX1		0x1D
161#define	CC2520_EXCBINDY0		0x1E
162#define	CC2520_EXCBINDY1		0x1F
163#define	CC2520_GPIOCTRL0		0x20
164#define	CC2520_GPIOCTRL1		0x21
165#define	CC2520_GPIOCTRL2		0x22
166#define	CC2520_GPIOCTRL3		0x23
167#define	CC2520_GPIOCTRL4		0x24
168#define	CC2520_GPIOCTRL5		0x25
169#define	CC2520_GPIOPOLARITY		0x26
170#define	CC2520_GPIOCTRL			0x28
171#define	CC2520_DPUCON			0x2A
172#define	CC2520_DPUSTAT			0x2C
173#define	CC2520_FREQCTRL			0x2E
174#define	CC2520_FREQTUNE			0x2F
175#define	CC2520_TXPOWER			0x30
176#define	CC2520_TXCTRL			0x31
177#define	CC2520_FSMSTAT0			0x32
178#define	CC2520_FSMSTAT1			0x33
179#define	CC2520_FIFOPCTRL		0x34
180#define	CC2520_FSMCTRL			0x35
181#define	CC2520_CCACTRL0			0x36
182#define	CC2520_CCACTRL1			0x37
183#define	CC2520_RSSI			0x38
184#define	CC2520_RSSISTAT			0x39
185#define	CC2520_RXFIRST			0x3C
186#define	CC2520_RXFIFOCNT		0x3E
187#define	CC2520_TXFIFOCNT		0x3F
188
189/* CC2520_FRMFILT0 */
190#define FRMFILT0_FRAME_FILTER_EN	BIT(0)
191#define FRMFILT0_PAN_COORDINATOR	BIT(1)
192
193/* CC2520_FRMCTRL0 */
194#define FRMCTRL0_AUTOACK		BIT(5)
195#define FRMCTRL0_AUTOCRC		BIT(6)
196
197/* CC2520_FRMCTRL1 */
198#define FRMCTRL1_SET_RXENMASK_ON_TX	BIT(0)
199#define FRMCTRL1_IGNORE_TX_UNDERF	BIT(1)
200
201/* Driver private information */
202struct cc2520_private {
203	struct spi_device *spi;		/* SPI device structure */
204	struct ieee802154_hw *hw;	/* IEEE-802.15.4 device */
205	u8 *buf;			/* SPI TX/Rx data buffer */
206	struct mutex buffer_mutex;	/* SPI buffer mutex */
207	bool is_tx;			/* Flag for sync b/w Tx and Rx */
208	bool amplified;			/* Flag for CC2591 */
209	int fifo_pin;			/* FIFO GPIO pin number */
210	struct work_struct fifop_irqwork;/* Workqueue for FIFOP */
211	spinlock_t lock;		/* Lock for is_tx*/
212	struct completion tx_complete;	/* Work completion for Tx */
213	bool promiscuous;               /* Flag for promiscuous mode */
214};
215
216/* Generic Functions */
217static int
218cc2520_cmd_strobe(struct cc2520_private *priv, u8 cmd)
219{
220	int ret;
221	struct spi_message msg;
222	struct spi_transfer xfer = {
223		.len = 0,
224		.tx_buf = priv->buf,
225		.rx_buf = priv->buf,
226	};
227
228	spi_message_init(&msg);
229	spi_message_add_tail(&xfer, &msg);
230
231	mutex_lock(&priv->buffer_mutex);
232	priv->buf[xfer.len++] = cmd;
233	dev_vdbg(&priv->spi->dev,
234		 "command strobe buf[0] = %02x\n",
235		 priv->buf[0]);
236
237	ret = spi_sync(priv->spi, &msg);
238	dev_vdbg(&priv->spi->dev,
239		 "buf[0] = %02x\n", priv->buf[0]);
240	mutex_unlock(&priv->buffer_mutex);
241
242	return ret;
243}
244
245static int
246cc2520_get_status(struct cc2520_private *priv, u8 *status)
247{
248	int ret;
249	struct spi_message msg;
250	struct spi_transfer xfer = {
251		.len = 0,
252		.tx_buf = priv->buf,
253		.rx_buf = priv->buf,
254	};
255
256	spi_message_init(&msg);
257	spi_message_add_tail(&xfer, &msg);
258
259	mutex_lock(&priv->buffer_mutex);
260	priv->buf[xfer.len++] = CC2520_CMD_SNOP;
261	dev_vdbg(&priv->spi->dev,
262		 "get status command buf[0] = %02x\n", priv->buf[0]);
263
264	ret = spi_sync(priv->spi, &msg);
265	if (!ret)
266		*status = priv->buf[0];
267	dev_vdbg(&priv->spi->dev,
268		 "buf[0] = %02x\n", priv->buf[0]);
269	mutex_unlock(&priv->buffer_mutex);
270
271	return ret;
272}
273
274static int
275cc2520_write_register(struct cc2520_private *priv, u8 reg, u8 value)
276{
277	int status;
278	struct spi_message msg;
279	struct spi_transfer xfer = {
280		.len = 0,
281		.tx_buf = priv->buf,
282		.rx_buf = priv->buf,
283	};
284
285	spi_message_init(&msg);
286	spi_message_add_tail(&xfer, &msg);
287
288	mutex_lock(&priv->buffer_mutex);
289
290	if (reg <= CC2520_FREG_MASK) {
291		priv->buf[xfer.len++] = CC2520_CMD_REGISTER_WRITE | reg;
292		priv->buf[xfer.len++] = value;
293	} else {
294		priv->buf[xfer.len++] = CC2520_CMD_MEMORY_WRITE;
295		priv->buf[xfer.len++] = reg;
296		priv->buf[xfer.len++] = value;
297	}
298	status = spi_sync(priv->spi, &msg);
299	if (msg.status)
300		status = msg.status;
301
302	mutex_unlock(&priv->buffer_mutex);
303
304	return status;
305}
306
307static int
308cc2520_write_ram(struct cc2520_private *priv, u16 reg, u8 len, u8 *data)
309{
310	int status;
311	struct spi_message msg;
312	struct spi_transfer xfer_head = {
313		.len        = 0,
314		.tx_buf        = priv->buf,
315		.rx_buf        = priv->buf,
316	};
317
318	struct spi_transfer xfer_buf = {
319		.len = len,
320		.tx_buf = data,
321	};
322
323	mutex_lock(&priv->buffer_mutex);
324	priv->buf[xfer_head.len++] = (CC2520_CMD_MEMORY_WRITE |
325						((reg >> 8) & 0xff));
326	priv->buf[xfer_head.len++] = reg & 0xff;
327
328	spi_message_init(&msg);
329	spi_message_add_tail(&xfer_head, &msg);
330	spi_message_add_tail(&xfer_buf, &msg);
331
332	status = spi_sync(priv->spi, &msg);
333	dev_dbg(&priv->spi->dev, "spi status = %d\n", status);
334	if (msg.status)
335		status = msg.status;
336
337	mutex_unlock(&priv->buffer_mutex);
338	return status;
339}
340
341static int
342cc2520_read_register(struct cc2520_private *priv, u8 reg, u8 *data)
343{
344	int status;
345	struct spi_message msg;
346	struct spi_transfer xfer1 = {
347		.len = 0,
348		.tx_buf = priv->buf,
349		.rx_buf = priv->buf,
350	};
351
352	struct spi_transfer xfer2 = {
353		.len = 1,
354		.rx_buf = data,
355	};
356
357	spi_message_init(&msg);
358	spi_message_add_tail(&xfer1, &msg);
359	spi_message_add_tail(&xfer2, &msg);
360
361	mutex_lock(&priv->buffer_mutex);
362	priv->buf[xfer1.len++] = CC2520_CMD_MEMORY_READ;
363	priv->buf[xfer1.len++] = reg;
364
365	status = spi_sync(priv->spi, &msg);
366	dev_dbg(&priv->spi->dev,
367		"spi status = %d\n", status);
368	if (msg.status)
369		status = msg.status;
370
371	mutex_unlock(&priv->buffer_mutex);
372
373	return status;
374}
375
376static int
377cc2520_write_txfifo(struct cc2520_private *priv, u8 pkt_len, u8 *data, u8 len)
378{
379	int status;
380
381	/* length byte must include FCS even
382	 * if it is calculated in the hardware
383	 */
384	int len_byte = pkt_len;
385
386	struct spi_message msg;
387
388	struct spi_transfer xfer_head = {
389		.len = 0,
390		.tx_buf = priv->buf,
391		.rx_buf = priv->buf,
392	};
393	struct spi_transfer xfer_len = {
394		.len = 1,
395		.tx_buf = &len_byte,
396	};
397	struct spi_transfer xfer_buf = {
398		.len = len,
399		.tx_buf = data,
400	};
401
402	spi_message_init(&msg);
403	spi_message_add_tail(&xfer_head, &msg);
404	spi_message_add_tail(&xfer_len, &msg);
405	spi_message_add_tail(&xfer_buf, &msg);
406
407	mutex_lock(&priv->buffer_mutex);
408	priv->buf[xfer_head.len++] = CC2520_CMD_TXBUF;
409	dev_vdbg(&priv->spi->dev,
410		 "TX_FIFO cmd buf[0] = %02x\n", priv->buf[0]);
411
412	status = spi_sync(priv->spi, &msg);
413	dev_vdbg(&priv->spi->dev, "status = %d\n", status);
414	if (msg.status)
415		status = msg.status;
416	dev_vdbg(&priv->spi->dev, "status = %d\n", status);
417	dev_vdbg(&priv->spi->dev, "buf[0] = %02x\n", priv->buf[0]);
418	mutex_unlock(&priv->buffer_mutex);
419
420	return status;
421}
422
423static int
424cc2520_read_rxfifo(struct cc2520_private *priv, u8 *data, u8 len)
425{
426	int status;
427	struct spi_message msg;
428
429	struct spi_transfer xfer_head = {
430		.len = 0,
431		.tx_buf = priv->buf,
432		.rx_buf = priv->buf,
433	};
434	struct spi_transfer xfer_buf = {
435		.len = len,
436		.rx_buf = data,
437	};
438
439	spi_message_init(&msg);
440	spi_message_add_tail(&xfer_head, &msg);
441	spi_message_add_tail(&xfer_buf, &msg);
442
443	mutex_lock(&priv->buffer_mutex);
444	priv->buf[xfer_head.len++] = CC2520_CMD_RXBUF;
445
446	dev_vdbg(&priv->spi->dev, "read rxfifo buf[0] = %02x\n", priv->buf[0]);
447	dev_vdbg(&priv->spi->dev, "buf[1] = %02x\n", priv->buf[1]);
448
449	status = spi_sync(priv->spi, &msg);
450	dev_vdbg(&priv->spi->dev, "status = %d\n", status);
451	if (msg.status)
452		status = msg.status;
453	dev_vdbg(&priv->spi->dev, "status = %d\n", status);
454	dev_vdbg(&priv->spi->dev,
455		 "return status buf[0] = %02x\n", priv->buf[0]);
456	dev_vdbg(&priv->spi->dev, "length buf[1] = %02x\n", priv->buf[1]);
457
458	mutex_unlock(&priv->buffer_mutex);
459
460	return status;
461}
462
463static int cc2520_start(struct ieee802154_hw *hw)
464{
465	return cc2520_cmd_strobe(hw->priv, CC2520_CMD_SRXON);
466}
467
468static void cc2520_stop(struct ieee802154_hw *hw)
469{
470	cc2520_cmd_strobe(hw->priv, CC2520_CMD_SRFOFF);
471}
472
473static int
474cc2520_tx(struct ieee802154_hw *hw, struct sk_buff *skb)
475{
476	struct cc2520_private *priv = hw->priv;
477	unsigned long flags;
478	int rc;
479	u8 status = 0;
480	u8 pkt_len;
481
482	/* In promiscuous mode we disable AUTOCRC so we can get the raw CRC
483	 * values on RX. This means we need to manually add the CRC on TX.
484	 */
485	if (priv->promiscuous) {
486		u16 crc = crc_ccitt(0, skb->data, skb->len);
487
488		put_unaligned_le16(crc, skb_put(skb, 2));
489		pkt_len = skb->len;
490	} else {
491		pkt_len = skb->len + 2;
492	}
493
494	rc = cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHTX);
495	if (rc)
496		goto err_tx;
497
498	rc = cc2520_write_txfifo(priv, pkt_len, skb->data, skb->len);
499	if (rc)
500		goto err_tx;
501
502	rc = cc2520_get_status(priv, &status);
503	if (rc)
504		goto err_tx;
505
506	if (status & CC2520_STATUS_TX_UNDERFLOW) {
507		rc = -EINVAL;
508		dev_err(&priv->spi->dev, "cc2520 tx underflow exception\n");
509		goto err_tx;
510	}
511
512	spin_lock_irqsave(&priv->lock, flags);
513	WARN_ON(priv->is_tx);
514	priv->is_tx = 1;
515	spin_unlock_irqrestore(&priv->lock, flags);
516
517	rc = cc2520_cmd_strobe(priv, CC2520_CMD_STXONCCA);
518	if (rc)
519		goto err;
520
521	rc = wait_for_completion_interruptible(&priv->tx_complete);
522	if (rc < 0)
523		goto err;
524
525	cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHTX);
526	cc2520_cmd_strobe(priv, CC2520_CMD_SRXON);
527
528	return rc;
529err:
530	spin_lock_irqsave(&priv->lock, flags);
531	priv->is_tx = 0;
532	spin_unlock_irqrestore(&priv->lock, flags);
533err_tx:
534	return rc;
535}
536
537static int cc2520_rx(struct cc2520_private *priv)
538{
539	u8 len = 0, lqi = 0, bytes = 1;
540	struct sk_buff *skb;
541
542	/* Read single length byte from the radio. */
543	cc2520_read_rxfifo(priv, &len, bytes);
544
545	if (!ieee802154_is_valid_psdu_len(len)) {
546		/* Corrupted frame received, clear frame buffer by
547		 * reading entire buffer.
548		 */
549		dev_dbg(&priv->spi->dev, "corrupted frame received\n");
550		len = IEEE802154_MTU;
551	}
552
553	skb = dev_alloc_skb(len);
554	if (!skb)
555		return -ENOMEM;
556
557	if (cc2520_read_rxfifo(priv, skb_put(skb, len), len)) {
558		dev_dbg(&priv->spi->dev, "frame reception failed\n");
559		kfree_skb(skb);
560		return -EINVAL;
561	}
562
563	/* In promiscuous mode, we configure the radio to include the
564	 * CRC (AUTOCRC==0) and we pass on the packet unconditionally. If not
565	 * in promiscuous mode, we check the CRC here, but leave the
566	 * RSSI/LQI/CRC_OK bytes as they will get removed in the mac layer.
567	 */
568	if (!priv->promiscuous) {
569		bool crc_ok;
570
571		/* Check if the CRC is valid. With AUTOCRC set, the most
572		 * significant bit of the last byte returned from the CC2520
573		 * is CRC_OK flag. See section 20.3.4 of the datasheet.
574		 */
575		crc_ok = skb->data[len - 1] & BIT(7);
576
577		/* If we failed CRC drop the packet in the driver layer. */
578		if (!crc_ok) {
579			dev_dbg(&priv->spi->dev, "CRC check failed\n");
580			kfree_skb(skb);
581			return -EINVAL;
582		}
583
584		/* To calculate LQI, the lower 7 bits of the last byte (the
585		 * correlation value provided by the radio) must be scaled to
586		 * the range 0-255. According to section 20.6, the correlation
587		 * value ranges from 50-110. Ideally this would be calibrated
588		 * per hardware design, but we use roughly the datasheet values
589		 * to get close enough while avoiding floating point.
590		 */
591		lqi = skb->data[len - 1] & 0x7f;
592		if (lqi < 50)
593			lqi = 50;
594		else if (lqi > 113)
595			lqi = 113;
596		lqi = (lqi - 50) * 4;
597	}
598
599	ieee802154_rx_irqsafe(priv->hw, skb, lqi);
600
601	dev_vdbg(&priv->spi->dev, "RXFIFO: %x %x\n", len, lqi);
602
603	return 0;
604}
605
606static int
607cc2520_ed(struct ieee802154_hw *hw, u8 *level)
608{
609	struct cc2520_private *priv = hw->priv;
610	u8 status = 0xff;
611	u8 rssi;
612	int ret;
613
614	ret = cc2520_read_register(priv, CC2520_RSSISTAT, &status);
615	if (ret)
616		return ret;
617
618	if (status != RSSI_VALID)
619		return -EINVAL;
620
621	ret = cc2520_read_register(priv, CC2520_RSSI, &rssi);
622	if (ret)
623		return ret;
624
625	/* level = RSSI(rssi) - OFFSET [dBm] : offset is 76dBm */
626	*level = rssi - RSSI_OFFSET;
627
628	return 0;
629}
630
631static int
632cc2520_set_channel(struct ieee802154_hw *hw, u8 page, u8 channel)
633{
634	struct cc2520_private *priv = hw->priv;
635	int ret;
636
637	dev_dbg(&priv->spi->dev, "trying to set channel\n");
638
639	WARN_ON(page != 0);
640	WARN_ON(channel < CC2520_MINCHANNEL);
641	WARN_ON(channel > CC2520_MAXCHANNEL);
642
643	ret = cc2520_write_register(priv, CC2520_FREQCTRL,
644				    11 + 5 * (channel - 11));
645
646	return ret;
647}
648
649static int
650cc2520_filter(struct ieee802154_hw *hw,
651	      struct ieee802154_hw_addr_filt *filt, unsigned long changed)
652{
653	struct cc2520_private *priv = hw->priv;
654	int ret = 0;
655
656	if (changed & IEEE802154_AFILT_PANID_CHANGED) {
657		u16 panid = le16_to_cpu(filt->pan_id);
658
659		dev_vdbg(&priv->spi->dev, "%s called for pan id\n", __func__);
660		ret = cc2520_write_ram(priv, CC2520RAM_PANID,
661				       sizeof(panid), (u8 *)&panid);
662	}
663
664	if (changed & IEEE802154_AFILT_IEEEADDR_CHANGED) {
665		dev_vdbg(&priv->spi->dev,
666			 "%s called for IEEE addr\n", __func__);
667		ret = cc2520_write_ram(priv, CC2520RAM_IEEEADDR,
668				       sizeof(filt->ieee_addr),
669				       (u8 *)&filt->ieee_addr);
670	}
671
672	if (changed & IEEE802154_AFILT_SADDR_CHANGED) {
673		u16 addr = le16_to_cpu(filt->short_addr);
674
675		dev_vdbg(&priv->spi->dev, "%s called for saddr\n", __func__);
676		ret = cc2520_write_ram(priv, CC2520RAM_SHORTADDR,
677				       sizeof(addr), (u8 *)&addr);
678	}
679
680	if (changed & IEEE802154_AFILT_PANC_CHANGED) {
681		u8 frmfilt0;
682
683		dev_vdbg(&priv->spi->dev,
684			 "%s called for panc change\n", __func__);
685
686		cc2520_read_register(priv, CC2520_FRMFILT0, &frmfilt0);
687
688		if (filt->pan_coord)
689			frmfilt0 |= FRMFILT0_PAN_COORDINATOR;
690		else
691			frmfilt0 &= ~FRMFILT0_PAN_COORDINATOR;
692
693		ret = cc2520_write_register(priv, CC2520_FRMFILT0, frmfilt0);
694	}
695
696	return ret;
697}
698
699static inline int cc2520_set_tx_power(struct cc2520_private *priv, s32 mbm)
700{
701	u8 power;
702
703	switch (mbm) {
704	case 500:
705		power = 0xF7;
706		break;
707	case 300:
708		power = 0xF2;
709		break;
710	case 200:
711		power = 0xAB;
712		break;
713	case 100:
714		power = 0x13;
715		break;
716	case 0:
717		power = 0x32;
718		break;
719	case -200:
720		power = 0x81;
721		break;
722	case -400:
723		power = 0x88;
724		break;
725	case -700:
726		power = 0x2C;
727		break;
728	case -1800:
729		power = 0x03;
730		break;
731	default:
732		return -EINVAL;
733	}
734
735	return cc2520_write_register(priv, CC2520_TXPOWER, power);
736}
737
738static inline int cc2520_cc2591_set_tx_power(struct cc2520_private *priv,
739					     s32 mbm)
740{
741	u8 power;
742
743	switch (mbm) {
744	case 1700:
745		power = 0xF9;
746		break;
747	case 1600:
748		power = 0xF0;
749		break;
750	case 1400:
751		power = 0xA0;
752		break;
753	case 1100:
754		power = 0x2C;
755		break;
756	case -100:
757		power = 0x03;
758		break;
759	case -800:
760		power = 0x01;
761		break;
762	default:
763		return -EINVAL;
764	}
765
766	return cc2520_write_register(priv, CC2520_TXPOWER, power);
767}
768
769#define CC2520_MAX_TX_POWERS 0x8
770static const s32 cc2520_powers[CC2520_MAX_TX_POWERS + 1] = {
771	500, 300, 200, 100, 0, -200, -400, -700, -1800,
772};
773
774#define CC2520_CC2591_MAX_TX_POWERS 0x5
775static const s32 cc2520_cc2591_powers[CC2520_CC2591_MAX_TX_POWERS + 1] = {
776	1700, 1600, 1400, 1100, -100, -800,
777};
778
779static int
780cc2520_set_txpower(struct ieee802154_hw *hw, s32 mbm)
781{
782	struct cc2520_private *priv = hw->priv;
783
784	if (!priv->amplified)
785		return cc2520_set_tx_power(priv, mbm);
786
787	return cc2520_cc2591_set_tx_power(priv, mbm);
788}
789
790static int
791cc2520_set_promiscuous_mode(struct ieee802154_hw *hw, bool on)
792{
793	struct cc2520_private *priv = hw->priv;
794	u8 frmfilt0;
795
796	dev_dbg(&priv->spi->dev, "%s : mode %d\n", __func__, on);
797
798	priv->promiscuous = on;
799
800	cc2520_read_register(priv, CC2520_FRMFILT0, &frmfilt0);
801
802	if (on) {
803		/* Disable automatic ACK, automatic CRC, and frame filtering. */
804		cc2520_write_register(priv, CC2520_FRMCTRL0, 0);
805		frmfilt0 &= ~FRMFILT0_FRAME_FILTER_EN;
806	} else {
807		cc2520_write_register(priv, CC2520_FRMCTRL0, FRMCTRL0_AUTOACK |
808							     FRMCTRL0_AUTOCRC);
809		frmfilt0 |= FRMFILT0_FRAME_FILTER_EN;
810	}
811	return cc2520_write_register(priv, CC2520_FRMFILT0, frmfilt0);
812}
813
814static const struct ieee802154_ops cc2520_ops = {
815	.owner = THIS_MODULE,
816	.start = cc2520_start,
817	.stop = cc2520_stop,
818	.xmit_sync = cc2520_tx,
819	.ed = cc2520_ed,
820	.set_channel = cc2520_set_channel,
821	.set_hw_addr_filt = cc2520_filter,
822	.set_txpower = cc2520_set_txpower,
823	.set_promiscuous_mode = cc2520_set_promiscuous_mode,
824};
825
826static int cc2520_register(struct cc2520_private *priv)
827{
828	int ret = -ENOMEM;
829
830	priv->hw = ieee802154_alloc_hw(sizeof(*priv), &cc2520_ops);
831	if (!priv->hw)
832		goto err_ret;
833
834	priv->hw->priv = priv;
835	priv->hw->parent = &priv->spi->dev;
836	priv->hw->extra_tx_headroom = 0;
837	ieee802154_random_extended_addr(&priv->hw->phy->perm_extended_addr);
838
839	/* We do support only 2.4 Ghz */
840	priv->hw->phy->supported.channels[0] = 0x7FFF800;
841	priv->hw->flags = IEEE802154_HW_TX_OMIT_CKSUM | IEEE802154_HW_AFILT |
842			  IEEE802154_HW_PROMISCUOUS;
843
844	priv->hw->phy->flags = WPAN_PHY_FLAG_TXPOWER;
845
846	if (!priv->amplified) {
847		priv->hw->phy->supported.tx_powers = cc2520_powers;
848		priv->hw->phy->supported.tx_powers_size = ARRAY_SIZE(cc2520_powers);
849		priv->hw->phy->transmit_power = priv->hw->phy->supported.tx_powers[4];
850	} else {
851		priv->hw->phy->supported.tx_powers = cc2520_cc2591_powers;
852		priv->hw->phy->supported.tx_powers_size = ARRAY_SIZE(cc2520_cc2591_powers);
853		priv->hw->phy->transmit_power = priv->hw->phy->supported.tx_powers[0];
854	}
855
856	priv->hw->phy->current_channel = 11;
857
858	dev_vdbg(&priv->spi->dev, "registered cc2520\n");
859	ret = ieee802154_register_hw(priv->hw);
860	if (ret)
861		goto err_free_device;
862
863	return 0;
864
865err_free_device:
866	ieee802154_free_hw(priv->hw);
867err_ret:
868	return ret;
869}
870
871static void cc2520_fifop_irqwork(struct work_struct *work)
872{
873	struct cc2520_private *priv
874		= container_of(work, struct cc2520_private, fifop_irqwork);
875
876	dev_dbg(&priv->spi->dev, "fifop interrupt received\n");
877
878	if (gpio_get_value(priv->fifo_pin))
879		cc2520_rx(priv);
880	else
881		dev_dbg(&priv->spi->dev, "rxfifo overflow\n");
882
883	cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHRX);
884	cc2520_cmd_strobe(priv, CC2520_CMD_SFLUSHRX);
885}
886
887static irqreturn_t cc2520_fifop_isr(int irq, void *data)
888{
889	struct cc2520_private *priv = data;
890
891	schedule_work(&priv->fifop_irqwork);
892
893	return IRQ_HANDLED;
894}
895
896static irqreturn_t cc2520_sfd_isr(int irq, void *data)
897{
898	struct cc2520_private *priv = data;
899	unsigned long flags;
900
901	spin_lock_irqsave(&priv->lock, flags);
902	if (priv->is_tx) {
903		priv->is_tx = 0;
904		spin_unlock_irqrestore(&priv->lock, flags);
905		dev_dbg(&priv->spi->dev, "SFD for TX\n");
906		complete(&priv->tx_complete);
907	} else {
908		spin_unlock_irqrestore(&priv->lock, flags);
909		dev_dbg(&priv->spi->dev, "SFD for RX\n");
910	}
911
912	return IRQ_HANDLED;
913}
914
915static int cc2520_get_platform_data(struct spi_device *spi,
916				    struct cc2520_platform_data *pdata)
917{
918	struct device_node *np = spi->dev.of_node;
919	struct cc2520_private *priv = spi_get_drvdata(spi);
920
921	if (!np) {
922		struct cc2520_platform_data *spi_pdata = spi->dev.platform_data;
923
924		if (!spi_pdata)
925			return -ENOENT;
926		*pdata = *spi_pdata;
927		priv->fifo_pin = pdata->fifo;
928		return 0;
929	}
930
931	pdata->fifo = of_get_named_gpio(np, "fifo-gpio", 0);
932	priv->fifo_pin = pdata->fifo;
933
934	pdata->fifop = of_get_named_gpio(np, "fifop-gpio", 0);
935
936	pdata->sfd = of_get_named_gpio(np, "sfd-gpio", 0);
937	pdata->cca = of_get_named_gpio(np, "cca-gpio", 0);
938	pdata->vreg = of_get_named_gpio(np, "vreg-gpio", 0);
939	pdata->reset = of_get_named_gpio(np, "reset-gpio", 0);
940
941	/* CC2591 front end for CC2520 */
942	if (of_property_read_bool(np, "amplified"))
943		priv->amplified = true;
944
945	return 0;
946}
947
948static int cc2520_hw_init(struct cc2520_private *priv)
949{
950	u8 status = 0, state = 0xff;
951	int ret;
952	int timeout = 100;
953	struct cc2520_platform_data pdata;
954
955	ret = cc2520_get_platform_data(priv->spi, &pdata);
956	if (ret)
957		goto err_ret;
958
959	ret = cc2520_read_register(priv, CC2520_FSMSTAT1, &state);
960	if (ret)
961		goto err_ret;
962
963	if (state != STATE_IDLE)
964		return -EINVAL;
965
966	do {
967		ret = cc2520_get_status(priv, &status);
968		if (ret)
969			goto err_ret;
970
971		if (timeout-- <= 0) {
972			dev_err(&priv->spi->dev, "oscillator start failed!\n");
973			return -ETIMEDOUT;
974		}
975		udelay(1);
976	} while (!(status & CC2520_STATUS_XOSC32M_STABLE));
977
978	dev_vdbg(&priv->spi->dev, "oscillator brought up\n");
979
980	/* If the CC2520 is connected to a CC2591 amplifier, we must both
981	 * configure GPIOs on the CC2520 to correctly configure the CC2591
982	 * and change a couple settings of the CC2520 to work with the
983	 * amplifier. See section 8 page 17 of TI application note AN065.
984	 * http://www.ti.com/lit/an/swra229a/swra229a.pdf
985	 */
986	if (priv->amplified) {
987		ret = cc2520_write_register(priv, CC2520_AGCCTRL1, 0x16);
988		if (ret)
989			goto err_ret;
990
991		ret = cc2520_write_register(priv, CC2520_GPIOCTRL0, 0x46);
992		if (ret)
993			goto err_ret;
994
995		ret = cc2520_write_register(priv, CC2520_GPIOCTRL5, 0x47);
996		if (ret)
997			goto err_ret;
998
999		ret = cc2520_write_register(priv, CC2520_GPIOPOLARITY, 0x1e);
1000		if (ret)
1001			goto err_ret;
1002
1003		ret = cc2520_write_register(priv, CC2520_TXCTRL, 0xc1);
1004		if (ret)
1005			goto err_ret;
1006	} else {
1007		ret = cc2520_write_register(priv, CC2520_AGCCTRL1, 0x11);
1008		if (ret)
1009			goto err_ret;
1010	}
1011
1012	/* Registers default value: section 28.1 in Datasheet */
1013
1014	/* Set the CCA threshold to -50 dBm. This seems to have been copied
1015	 * from the TinyOS CC2520 driver and is much higher than the -84 dBm
1016	 * threshold suggested in the datasheet.
1017	 */
1018	ret = cc2520_write_register(priv, CC2520_CCACTRL0, 0x1A);
1019	if (ret)
1020		goto err_ret;
1021
1022	ret = cc2520_write_register(priv, CC2520_MDMCTRL0, 0x85);
1023	if (ret)
1024		goto err_ret;
1025
1026	ret = cc2520_write_register(priv, CC2520_MDMCTRL1, 0x14);
1027	if (ret)
1028		goto err_ret;
1029
1030	ret = cc2520_write_register(priv, CC2520_RXCTRL, 0x3f);
1031	if (ret)
1032		goto err_ret;
1033
1034	ret = cc2520_write_register(priv, CC2520_FSCTRL, 0x5a);
1035	if (ret)
1036		goto err_ret;
1037
1038	ret = cc2520_write_register(priv, CC2520_FSCAL1, 0x2b);
1039	if (ret)
1040		goto err_ret;
1041
1042	ret = cc2520_write_register(priv, CC2520_ADCTEST0, 0x10);
1043	if (ret)
1044		goto err_ret;
1045
1046	ret = cc2520_write_register(priv, CC2520_ADCTEST1, 0x0e);
1047	if (ret)
1048		goto err_ret;
1049
1050	ret = cc2520_write_register(priv, CC2520_ADCTEST2, 0x03);
1051	if (ret)
1052		goto err_ret;
1053
1054	/* Configure registers correctly for this driver. */
1055	ret = cc2520_write_register(priv, CC2520_FRMCTRL1,
1056				    FRMCTRL1_SET_RXENMASK_ON_TX |
1057				    FRMCTRL1_IGNORE_TX_UNDERF);
1058	if (ret)
1059		goto err_ret;
1060
1061	ret = cc2520_write_register(priv, CC2520_FIFOPCTRL, 127);
1062	if (ret)
1063		goto err_ret;
1064
1065	return 0;
1066
1067err_ret:
1068	return ret;
1069}
1070
1071static int cc2520_probe(struct spi_device *spi)
1072{
1073	struct cc2520_private *priv;
1074	struct cc2520_platform_data pdata;
1075	int ret;
1076
1077	priv = devm_kzalloc(&spi->dev, sizeof(*priv), GFP_KERNEL);
1078	if (!priv)
1079		return -ENOMEM;
1080
1081	spi_set_drvdata(spi, priv);
1082
1083	ret = cc2520_get_platform_data(spi, &pdata);
1084	if (ret < 0) {
1085		dev_err(&spi->dev, "no platform data\n");
1086		return -EINVAL;
1087	}
1088
1089	priv->spi = spi;
1090
1091	priv->buf = devm_kzalloc(&spi->dev,
1092				 SPI_COMMAND_BUFFER, GFP_KERNEL);
1093	if (!priv->buf)
1094		return -ENOMEM;
1095
1096	mutex_init(&priv->buffer_mutex);
1097	INIT_WORK(&priv->fifop_irqwork, cc2520_fifop_irqwork);
1098	spin_lock_init(&priv->lock);
1099	init_completion(&priv->tx_complete);
1100
1101	/* Assumption that CC2591 is not connected */
1102	priv->amplified = false;
1103
1104	/* Request all the gpio's */
1105	if (!gpio_is_valid(pdata.fifo)) {
1106		dev_err(&spi->dev, "fifo gpio is not valid\n");
1107		ret = -EINVAL;
1108		goto err_hw_init;
1109	}
1110
1111	ret = devm_gpio_request_one(&spi->dev, pdata.fifo,
1112				    GPIOF_IN, "fifo");
1113	if (ret)
1114		goto err_hw_init;
1115
1116	if (!gpio_is_valid(pdata.cca)) {
1117		dev_err(&spi->dev, "cca gpio is not valid\n");
1118		ret = -EINVAL;
1119		goto err_hw_init;
1120	}
1121
1122	ret = devm_gpio_request_one(&spi->dev, pdata.cca,
1123				    GPIOF_IN, "cca");
1124	if (ret)
1125		goto err_hw_init;
1126
1127	if (!gpio_is_valid(pdata.fifop)) {
1128		dev_err(&spi->dev, "fifop gpio is not valid\n");
1129		ret = -EINVAL;
1130		goto err_hw_init;
1131	}
1132
1133	ret = devm_gpio_request_one(&spi->dev, pdata.fifop,
1134				    GPIOF_IN, "fifop");
1135	if (ret)
1136		goto err_hw_init;
1137
1138	if (!gpio_is_valid(pdata.sfd)) {
1139		dev_err(&spi->dev, "sfd gpio is not valid\n");
1140		ret = -EINVAL;
1141		goto err_hw_init;
1142	}
1143
1144	ret = devm_gpio_request_one(&spi->dev, pdata.sfd,
1145				    GPIOF_IN, "sfd");
1146	if (ret)
1147		goto err_hw_init;
1148
1149	if (!gpio_is_valid(pdata.reset)) {
1150		dev_err(&spi->dev, "reset gpio is not valid\n");
1151		ret = -EINVAL;
1152		goto err_hw_init;
1153	}
1154
1155	ret = devm_gpio_request_one(&spi->dev, pdata.reset,
1156				    GPIOF_OUT_INIT_LOW, "reset");
1157	if (ret)
1158		goto err_hw_init;
1159
1160	if (!gpio_is_valid(pdata.vreg)) {
1161		dev_err(&spi->dev, "vreg gpio is not valid\n");
1162		ret = -EINVAL;
1163		goto err_hw_init;
1164	}
1165
1166	ret = devm_gpio_request_one(&spi->dev, pdata.vreg,
1167				    GPIOF_OUT_INIT_LOW, "vreg");
1168	if (ret)
1169		goto err_hw_init;
1170
1171	gpio_set_value(pdata.vreg, HIGH);
1172	usleep_range(100, 150);
1173
1174	gpio_set_value(pdata.reset, HIGH);
1175	usleep_range(200, 250);
1176
1177	ret = cc2520_hw_init(priv);
1178	if (ret)
1179		goto err_hw_init;
1180
1181	/* Set up fifop interrupt */
1182	ret = devm_request_irq(&spi->dev,
1183			       gpio_to_irq(pdata.fifop),
1184			       cc2520_fifop_isr,
1185			       IRQF_TRIGGER_RISING,
1186			       dev_name(&spi->dev),
1187			       priv);
1188	if (ret) {
1189		dev_err(&spi->dev, "could not get fifop irq\n");
1190		goto err_hw_init;
1191	}
1192
1193	/* Set up sfd interrupt */
1194	ret = devm_request_irq(&spi->dev,
1195			       gpio_to_irq(pdata.sfd),
1196			       cc2520_sfd_isr,
1197			       IRQF_TRIGGER_FALLING,
1198			       dev_name(&spi->dev),
1199			       priv);
1200	if (ret) {
1201		dev_err(&spi->dev, "could not get sfd irq\n");
1202		goto err_hw_init;
1203	}
1204
1205	ret = cc2520_register(priv);
1206	if (ret)
1207		goto err_hw_init;
1208
1209	return 0;
1210
1211err_hw_init:
1212	mutex_destroy(&priv->buffer_mutex);
1213	flush_work(&priv->fifop_irqwork);
1214	return ret;
1215}
1216
1217static int cc2520_remove(struct spi_device *spi)
1218{
1219	struct cc2520_private *priv = spi_get_drvdata(spi);
1220
1221	mutex_destroy(&priv->buffer_mutex);
1222	flush_work(&priv->fifop_irqwork);
1223
1224	ieee802154_unregister_hw(priv->hw);
1225	ieee802154_free_hw(priv->hw);
1226
1227	return 0;
1228}
1229
1230static const struct spi_device_id cc2520_ids[] = {
1231	{"cc2520", },
1232	{},
1233};
1234MODULE_DEVICE_TABLE(spi, cc2520_ids);
1235
1236static const struct of_device_id cc2520_of_ids[] = {
1237	{.compatible = "ti,cc2520", },
1238	{},
1239};
1240MODULE_DEVICE_TABLE(of, cc2520_of_ids);
1241
1242/* SPI driver structure */
1243static struct spi_driver cc2520_driver = {
1244	.driver = {
1245		.name = "cc2520",
1246		.of_match_table = of_match_ptr(cc2520_of_ids),
1247	},
1248	.id_table = cc2520_ids,
1249	.probe = cc2520_probe,
1250	.remove = cc2520_remove,
1251};
1252module_spi_driver(cc2520_driver);
1253
1254MODULE_AUTHOR("Varka Bhadram <varkab@cdac.in>");
1255MODULE_DESCRIPTION("CC2520 Transceiver Driver");
1256MODULE_LICENSE("GPL v2");
1257