xref: /openbmc/linux/drivers/spi/spi-bcm63xx.c (revision 44d8fb30)
1 /*
2  * Broadcom BCM63xx SPI controller support
3  *
4  * Copyright (C) 2009-2012 Florian Fainelli <florian@openwrt.org>
5  * Copyright (C) 2010 Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License
9  * as published by the Free Software Foundation; either version 2
10  * of the License, or (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  */
17 
18 #include <linux/kernel.h>
19 #include <linux/clk.h>
20 #include <linux/io.h>
21 #include <linux/module.h>
22 #include <linux/platform_device.h>
23 #include <linux/delay.h>
24 #include <linux/interrupt.h>
25 #include <linux/spi/spi.h>
26 #include <linux/completion.h>
27 #include <linux/err.h>
28 #include <linux/pm_runtime.h>
29 
30 /* BCM 6338/6348 SPI core */
31 #define SPI_6348_RSET_SIZE		64
32 #define SPI_6348_CMD			0x00	/* 16-bits register */
33 #define SPI_6348_INT_STATUS		0x02
34 #define SPI_6348_INT_MASK_ST		0x03
35 #define SPI_6348_INT_MASK		0x04
36 #define SPI_6348_ST			0x05
37 #define SPI_6348_CLK_CFG		0x06
38 #define SPI_6348_FILL_BYTE		0x07
39 #define SPI_6348_MSG_TAIL		0x09
40 #define SPI_6348_RX_TAIL		0x0b
41 #define SPI_6348_MSG_CTL		0x40	/* 8-bits register */
42 #define SPI_6348_MSG_CTL_WIDTH		8
43 #define SPI_6348_MSG_DATA		0x41
44 #define SPI_6348_MSG_DATA_SIZE		0x3f
45 #define SPI_6348_RX_DATA		0x80
46 #define SPI_6348_RX_DATA_SIZE		0x3f
47 
48 /* BCM 3368/6358/6262/6368 SPI core */
49 #define SPI_6358_RSET_SIZE		1804
50 #define SPI_6358_MSG_CTL		0x00	/* 16-bits register */
51 #define SPI_6358_MSG_CTL_WIDTH		16
52 #define SPI_6358_MSG_DATA		0x02
53 #define SPI_6358_MSG_DATA_SIZE		0x21e
54 #define SPI_6358_RX_DATA		0x400
55 #define SPI_6358_RX_DATA_SIZE		0x220
56 #define SPI_6358_CMD			0x700	/* 16-bits register */
57 #define SPI_6358_INT_STATUS		0x702
58 #define SPI_6358_INT_MASK_ST		0x703
59 #define SPI_6358_INT_MASK		0x704
60 #define SPI_6358_ST			0x705
61 #define SPI_6358_CLK_CFG		0x706
62 #define SPI_6358_FILL_BYTE		0x707
63 #define SPI_6358_MSG_TAIL		0x709
64 #define SPI_6358_RX_TAIL		0x70B
65 
66 /* Shared SPI definitions */
67 
68 /* Message configuration */
69 #define SPI_FD_RW			0x00
70 #define SPI_HD_W			0x01
71 #define SPI_HD_R			0x02
72 #define SPI_BYTE_CNT_SHIFT		0
73 #define SPI_6348_MSG_TYPE_SHIFT		6
74 #define SPI_6358_MSG_TYPE_SHIFT		14
75 
76 /* Command */
77 #define SPI_CMD_NOOP			0x00
78 #define SPI_CMD_SOFT_RESET		0x01
79 #define SPI_CMD_HARD_RESET		0x02
80 #define SPI_CMD_START_IMMEDIATE		0x03
81 #define SPI_CMD_COMMAND_SHIFT		0
82 #define SPI_CMD_COMMAND_MASK		0x000f
83 #define SPI_CMD_DEVICE_ID_SHIFT		4
84 #define SPI_CMD_PREPEND_BYTE_CNT_SHIFT	8
85 #define SPI_CMD_ONE_BYTE_SHIFT		11
86 #define SPI_CMD_ONE_WIRE_SHIFT		12
87 #define SPI_DEV_ID_0			0
88 #define SPI_DEV_ID_1			1
89 #define SPI_DEV_ID_2			2
90 #define SPI_DEV_ID_3			3
91 
92 /* Interrupt mask */
93 #define SPI_INTR_CMD_DONE		0x01
94 #define SPI_INTR_RX_OVERFLOW		0x02
95 #define SPI_INTR_TX_UNDERFLOW		0x04
96 #define SPI_INTR_TX_OVERFLOW		0x08
97 #define SPI_INTR_RX_UNDERFLOW		0x10
98 #define SPI_INTR_CLEAR_ALL		0x1f
99 
100 /* Status */
101 #define SPI_RX_EMPTY			0x02
102 #define SPI_CMD_BUSY			0x04
103 #define SPI_SERIAL_BUSY			0x08
104 
105 /* Clock configuration */
106 #define SPI_CLK_20MHZ			0x00
107 #define SPI_CLK_0_391MHZ		0x01
108 #define SPI_CLK_0_781MHZ		0x02	/* default */
109 #define SPI_CLK_1_563MHZ		0x03
110 #define SPI_CLK_3_125MHZ		0x04
111 #define SPI_CLK_6_250MHZ		0x05
112 #define SPI_CLK_12_50MHZ		0x06
113 #define SPI_CLK_MASK			0x07
114 #define SPI_SSOFFTIME_MASK		0x38
115 #define SPI_SSOFFTIME_SHIFT		3
116 #define SPI_BYTE_SWAP			0x80
117 
118 enum bcm63xx_regs_spi {
119 	SPI_CMD,
120 	SPI_INT_STATUS,
121 	SPI_INT_MASK_ST,
122 	SPI_INT_MASK,
123 	SPI_ST,
124 	SPI_CLK_CFG,
125 	SPI_FILL_BYTE,
126 	SPI_MSG_TAIL,
127 	SPI_RX_TAIL,
128 	SPI_MSG_CTL,
129 	SPI_MSG_DATA,
130 	SPI_RX_DATA,
131 	SPI_MSG_TYPE_SHIFT,
132 	SPI_MSG_CTL_WIDTH,
133 	SPI_MSG_DATA_SIZE,
134 };
135 
136 #define BCM63XX_SPI_MAX_PREPEND		15
137 
138 #define BCM63XX_SPI_MAX_CS		8
139 #define BCM63XX_SPI_BUS_NUM		0
140 
141 struct bcm63xx_spi {
142 	struct completion	done;
143 
144 	void __iomem		*regs;
145 	int			irq;
146 
147 	/* Platform data */
148 	const unsigned long	*reg_offsets;
149 	unsigned		fifo_size;
150 	unsigned int		msg_type_shift;
151 	unsigned int		msg_ctl_width;
152 
153 	/* data iomem */
154 	u8 __iomem		*tx_io;
155 	const u8 __iomem	*rx_io;
156 
157 	struct clk		*clk;
158 	struct platform_device	*pdev;
159 };
160 
161 static inline u8 bcm_spi_readb(struct bcm63xx_spi *bs,
162 			       unsigned int offset)
163 {
164 	return readb(bs->regs + bs->reg_offsets[offset]);
165 }
166 
167 static inline u16 bcm_spi_readw(struct bcm63xx_spi *bs,
168 				unsigned int offset)
169 {
170 #ifdef CONFIG_CPU_BIG_ENDIAN
171 	return ioread16be(bs->regs + bs->reg_offsets[offset]);
172 #else
173 	return readw(bs->regs + bs->reg_offsets[offset]);
174 #endif
175 }
176 
177 static inline void bcm_spi_writeb(struct bcm63xx_spi *bs,
178 				  u8 value, unsigned int offset)
179 {
180 	writeb(value, bs->regs + bs->reg_offsets[offset]);
181 }
182 
183 static inline void bcm_spi_writew(struct bcm63xx_spi *bs,
184 				  u16 value, unsigned int offset)
185 {
186 #ifdef CONFIG_CPU_BIG_ENDIAN
187 	iowrite16be(value, bs->regs + bs->reg_offsets[offset]);
188 #else
189 	writew(value, bs->regs + bs->reg_offsets[offset]);
190 #endif
191 }
192 
193 static const unsigned bcm63xx_spi_freq_table[SPI_CLK_MASK][2] = {
194 	{ 20000000, SPI_CLK_20MHZ },
195 	{ 12500000, SPI_CLK_12_50MHZ },
196 	{  6250000, SPI_CLK_6_250MHZ },
197 	{  3125000, SPI_CLK_3_125MHZ },
198 	{  1563000, SPI_CLK_1_563MHZ },
199 	{   781000, SPI_CLK_0_781MHZ },
200 	{   391000, SPI_CLK_0_391MHZ }
201 };
202 
203 static void bcm63xx_spi_setup_transfer(struct spi_device *spi,
204 				      struct spi_transfer *t)
205 {
206 	struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
207 	u8 clk_cfg, reg;
208 	int i;
209 
210 	/* Find the closest clock configuration */
211 	for (i = 0; i < SPI_CLK_MASK; i++) {
212 		if (t->speed_hz >= bcm63xx_spi_freq_table[i][0]) {
213 			clk_cfg = bcm63xx_spi_freq_table[i][1];
214 			break;
215 		}
216 	}
217 
218 	/* No matching configuration found, default to lowest */
219 	if (i == SPI_CLK_MASK)
220 		clk_cfg = SPI_CLK_0_391MHZ;
221 
222 	/* clear existing clock configuration bits of the register */
223 	reg = bcm_spi_readb(bs, SPI_CLK_CFG);
224 	reg &= ~SPI_CLK_MASK;
225 	reg |= clk_cfg;
226 
227 	bcm_spi_writeb(bs, reg, SPI_CLK_CFG);
228 	dev_dbg(&spi->dev, "Setting clock register to %02x (hz %d)\n",
229 		clk_cfg, t->speed_hz);
230 }
231 
232 /* the spi->mode bits understood by this driver: */
233 #define MODEBITS (SPI_CPOL | SPI_CPHA)
234 
235 static int bcm63xx_txrx_bufs(struct spi_device *spi, struct spi_transfer *first,
236 				unsigned int num_transfers)
237 {
238 	struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
239 	u16 msg_ctl;
240 	u16 cmd;
241 	unsigned int i, timeout = 0, prepend_len = 0, len = 0;
242 	struct spi_transfer *t = first;
243 	bool do_rx = false;
244 	bool do_tx = false;
245 
246 	/* Disable the CMD_DONE interrupt */
247 	bcm_spi_writeb(bs, 0, SPI_INT_MASK);
248 
249 	dev_dbg(&spi->dev, "txrx: tx %p, rx %p, len %d\n",
250 		t->tx_buf, t->rx_buf, t->len);
251 
252 	if (num_transfers > 1 && t->tx_buf && t->len <= BCM63XX_SPI_MAX_PREPEND)
253 		prepend_len = t->len;
254 
255 	/* prepare the buffer */
256 	for (i = 0; i < num_transfers; i++) {
257 		if (t->tx_buf) {
258 			do_tx = true;
259 			memcpy_toio(bs->tx_io + len, t->tx_buf, t->len);
260 
261 			/* don't prepend more than one tx */
262 			if (t != first)
263 				prepend_len = 0;
264 		}
265 
266 		if (t->rx_buf) {
267 			do_rx = true;
268 			/* prepend is half-duplex write only */
269 			if (t == first)
270 				prepend_len = 0;
271 		}
272 
273 		len += t->len;
274 
275 		t = list_entry(t->transfer_list.next, struct spi_transfer,
276 			       transfer_list);
277 	}
278 
279 	reinit_completion(&bs->done);
280 
281 	/* Fill in the Message control register */
282 	msg_ctl = (len << SPI_BYTE_CNT_SHIFT);
283 
284 	if (do_rx && do_tx && prepend_len == 0)
285 		msg_ctl |= (SPI_FD_RW << bs->msg_type_shift);
286 	else if (do_rx)
287 		msg_ctl |= (SPI_HD_R << bs->msg_type_shift);
288 	else if (do_tx)
289 		msg_ctl |= (SPI_HD_W << bs->msg_type_shift);
290 
291 	switch (bs->msg_ctl_width) {
292 	case 8:
293 		bcm_spi_writeb(bs, msg_ctl, SPI_MSG_CTL);
294 		break;
295 	case 16:
296 		bcm_spi_writew(bs, msg_ctl, SPI_MSG_CTL);
297 		break;
298 	}
299 
300 	/* Issue the transfer */
301 	cmd = SPI_CMD_START_IMMEDIATE;
302 	cmd |= (prepend_len << SPI_CMD_PREPEND_BYTE_CNT_SHIFT);
303 	cmd |= (spi->chip_select << SPI_CMD_DEVICE_ID_SHIFT);
304 	bcm_spi_writew(bs, cmd, SPI_CMD);
305 
306 	/* Enable the CMD_DONE interrupt */
307 	bcm_spi_writeb(bs, SPI_INTR_CMD_DONE, SPI_INT_MASK);
308 
309 	timeout = wait_for_completion_timeout(&bs->done, HZ);
310 	if (!timeout)
311 		return -ETIMEDOUT;
312 
313 	if (!do_rx)
314 		return 0;
315 
316 	len = 0;
317 	t = first;
318 	/* Read out all the data */
319 	for (i = 0; i < num_transfers; i++) {
320 		if (t->rx_buf)
321 			memcpy_fromio(t->rx_buf, bs->rx_io + len, t->len);
322 
323 		if (t != first || prepend_len == 0)
324 			len += t->len;
325 
326 		t = list_entry(t->transfer_list.next, struct spi_transfer,
327 			       transfer_list);
328 	}
329 
330 	return 0;
331 }
332 
333 static int bcm63xx_spi_transfer_one(struct spi_master *master,
334 					struct spi_message *m)
335 {
336 	struct bcm63xx_spi *bs = spi_master_get_devdata(master);
337 	struct spi_transfer *t, *first = NULL;
338 	struct spi_device *spi = m->spi;
339 	int status = 0;
340 	unsigned int n_transfers = 0, total_len = 0;
341 	bool can_use_prepend = false;
342 
343 	/*
344 	 * This SPI controller does not support keeping CS active after a
345 	 * transfer.
346 	 * Work around this by merging as many transfers we can into one big
347 	 * full-duplex transfers.
348 	 */
349 	list_for_each_entry(t, &m->transfers, transfer_list) {
350 		if (!first)
351 			first = t;
352 
353 		n_transfers++;
354 		total_len += t->len;
355 
356 		if (n_transfers == 2 && !first->rx_buf && !t->tx_buf &&
357 		    first->len <= BCM63XX_SPI_MAX_PREPEND)
358 			can_use_prepend = true;
359 		else if (can_use_prepend && t->tx_buf)
360 			can_use_prepend = false;
361 
362 		/* we can only transfer one fifo worth of data */
363 		if ((can_use_prepend &&
364 		     total_len > (bs->fifo_size + BCM63XX_SPI_MAX_PREPEND)) ||
365 		    (!can_use_prepend && total_len > bs->fifo_size)) {
366 			dev_err(&spi->dev, "unable to do transfers larger than FIFO size (%i > %i)\n",
367 				total_len, bs->fifo_size);
368 			status = -EINVAL;
369 			goto exit;
370 		}
371 
372 		/* all combined transfers have to have the same speed */
373 		if (t->speed_hz != first->speed_hz) {
374 			dev_err(&spi->dev, "unable to change speed between transfers\n");
375 			status = -EINVAL;
376 			goto exit;
377 		}
378 
379 		/* CS will be deasserted directly after transfer */
380 		if (t->delay_usecs) {
381 			dev_err(&spi->dev, "unable to keep CS asserted after transfer\n");
382 			status = -EINVAL;
383 			goto exit;
384 		}
385 
386 		if (t->cs_change ||
387 		    list_is_last(&t->transfer_list, &m->transfers)) {
388 			/* configure adapter for a new transfer */
389 			bcm63xx_spi_setup_transfer(spi, first);
390 
391 			/* send the data */
392 			status = bcm63xx_txrx_bufs(spi, first, n_transfers);
393 			if (status)
394 				goto exit;
395 
396 			m->actual_length += total_len;
397 
398 			first = NULL;
399 			n_transfers = 0;
400 			total_len = 0;
401 			can_use_prepend = false;
402 		}
403 	}
404 exit:
405 	m->status = status;
406 	spi_finalize_current_message(master);
407 
408 	return 0;
409 }
410 
411 /* This driver supports single master mode only. Hence
412  * CMD_DONE is the only interrupt we care about
413  */
414 static irqreturn_t bcm63xx_spi_interrupt(int irq, void *dev_id)
415 {
416 	struct spi_master *master = (struct spi_master *)dev_id;
417 	struct bcm63xx_spi *bs = spi_master_get_devdata(master);
418 	u8 intr;
419 
420 	/* Read interupts and clear them immediately */
421 	intr = bcm_spi_readb(bs, SPI_INT_STATUS);
422 	bcm_spi_writeb(bs, SPI_INTR_CLEAR_ALL, SPI_INT_STATUS);
423 	bcm_spi_writeb(bs, 0, SPI_INT_MASK);
424 
425 	/* A transfer completed */
426 	if (intr & SPI_INTR_CMD_DONE)
427 		complete(&bs->done);
428 
429 	return IRQ_HANDLED;
430 }
431 
432 static const unsigned long bcm6348_spi_reg_offsets[] = {
433 	[SPI_CMD]		= SPI_6348_CMD,
434 	[SPI_INT_STATUS]	= SPI_6348_INT_STATUS,
435 	[SPI_INT_MASK_ST]	= SPI_6348_INT_MASK_ST,
436 	[SPI_INT_MASK]		= SPI_6348_INT_MASK,
437 	[SPI_ST]		= SPI_6348_ST,
438 	[SPI_CLK_CFG]		= SPI_6348_CLK_CFG,
439 	[SPI_FILL_BYTE]		= SPI_6348_FILL_BYTE,
440 	[SPI_MSG_TAIL]		= SPI_6348_MSG_TAIL,
441 	[SPI_RX_TAIL]		= SPI_6348_RX_TAIL,
442 	[SPI_MSG_CTL]		= SPI_6348_MSG_CTL,
443 	[SPI_MSG_DATA]		= SPI_6348_MSG_DATA,
444 	[SPI_RX_DATA]		= SPI_6348_RX_DATA,
445 	[SPI_MSG_TYPE_SHIFT]	= SPI_6348_MSG_TYPE_SHIFT,
446 	[SPI_MSG_CTL_WIDTH]	= SPI_6348_MSG_CTL_WIDTH,
447 	[SPI_MSG_DATA_SIZE]	= SPI_6348_MSG_DATA_SIZE,
448 };
449 
450 static const unsigned long bcm6358_spi_reg_offsets[] = {
451 	[SPI_CMD]		= SPI_6358_CMD,
452 	[SPI_INT_STATUS]	= SPI_6358_INT_STATUS,
453 	[SPI_INT_MASK_ST]	= SPI_6358_INT_MASK_ST,
454 	[SPI_INT_MASK]		= SPI_6358_INT_MASK,
455 	[SPI_ST]		= SPI_6358_ST,
456 	[SPI_CLK_CFG]		= SPI_6358_CLK_CFG,
457 	[SPI_FILL_BYTE]		= SPI_6358_FILL_BYTE,
458 	[SPI_MSG_TAIL]		= SPI_6358_MSG_TAIL,
459 	[SPI_RX_TAIL]		= SPI_6358_RX_TAIL,
460 	[SPI_MSG_CTL]		= SPI_6358_MSG_CTL,
461 	[SPI_MSG_DATA]		= SPI_6358_MSG_DATA,
462 	[SPI_RX_DATA]		= SPI_6358_RX_DATA,
463 	[SPI_MSG_TYPE_SHIFT]	= SPI_6358_MSG_TYPE_SHIFT,
464 	[SPI_MSG_CTL_WIDTH]	= SPI_6358_MSG_CTL_WIDTH,
465 	[SPI_MSG_DATA_SIZE]	= SPI_6358_MSG_DATA_SIZE,
466 };
467 
468 static const struct platform_device_id bcm63xx_spi_dev_match[] = {
469 	{
470 		.name = "bcm6348-spi",
471 		.driver_data = (unsigned long)bcm6348_spi_reg_offsets,
472 	},
473 	{
474 		.name = "bcm6358-spi",
475 		.driver_data = (unsigned long)bcm6358_spi_reg_offsets,
476 	},
477 	{
478 	},
479 };
480 
481 static int bcm63xx_spi_probe(struct platform_device *pdev)
482 {
483 	struct resource *r;
484 	const unsigned long *bcm63xx_spireg;
485 	struct device *dev = &pdev->dev;
486 	int irq;
487 	struct spi_master *master;
488 	struct clk *clk;
489 	struct bcm63xx_spi *bs;
490 	int ret;
491 
492 	if (!pdev->id_entry->driver_data)
493 		return -EINVAL;
494 
495 	bcm63xx_spireg = (const unsigned long *)pdev->id_entry->driver_data;
496 
497 	irq = platform_get_irq(pdev, 0);
498 	if (irq < 0) {
499 		dev_err(dev, "no irq\n");
500 		return -ENXIO;
501 	}
502 
503 	clk = devm_clk_get(dev, "spi");
504 	if (IS_ERR(clk)) {
505 		dev_err(dev, "no clock for device\n");
506 		return PTR_ERR(clk);
507 	}
508 
509 	master = spi_alloc_master(dev, sizeof(*bs));
510 	if (!master) {
511 		dev_err(dev, "out of memory\n");
512 		return -ENOMEM;
513 	}
514 
515 	bs = spi_master_get_devdata(master);
516 	init_completion(&bs->done);
517 
518 	platform_set_drvdata(pdev, master);
519 	bs->pdev = pdev;
520 
521 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
522 	bs->regs = devm_ioremap_resource(&pdev->dev, r);
523 	if (IS_ERR(bs->regs)) {
524 		ret = PTR_ERR(bs->regs);
525 		goto out_err;
526 	}
527 
528 	bs->irq = irq;
529 	bs->clk = clk;
530 	bs->reg_offsets = bcm63xx_spireg;
531 	bs->fifo_size = bs->reg_offsets[SPI_MSG_DATA_SIZE];
532 
533 	ret = devm_request_irq(&pdev->dev, irq, bcm63xx_spi_interrupt, 0,
534 							pdev->name, master);
535 	if (ret) {
536 		dev_err(dev, "unable to request irq\n");
537 		goto out_err;
538 	}
539 
540 	master->bus_num = BCM63XX_SPI_BUS_NUM;
541 	master->num_chipselect = BCM63XX_SPI_MAX_CS;
542 	master->transfer_one_message = bcm63xx_spi_transfer_one;
543 	master->mode_bits = MODEBITS;
544 	master->bits_per_word_mask = SPI_BPW_MASK(8);
545 	master->auto_runtime_pm = true;
546 	bs->msg_type_shift = bs->reg_offsets[SPI_MSG_TYPE_SHIFT];
547 	bs->msg_ctl_width = bs->reg_offsets[SPI_MSG_CTL_WIDTH];
548 	bs->tx_io = (u8 *)(bs->regs + bs->reg_offsets[SPI_MSG_DATA]);
549 	bs->rx_io = (const u8 *)(bs->regs + bs->reg_offsets[SPI_RX_DATA]);
550 
551 	/* Initialize hardware */
552 	ret = clk_prepare_enable(bs->clk);
553 	if (ret)
554 		goto out_err;
555 
556 	bcm_spi_writeb(bs, SPI_INTR_CLEAR_ALL, SPI_INT_STATUS);
557 
558 	/* register and we are done */
559 	ret = devm_spi_register_master(dev, master);
560 	if (ret) {
561 		dev_err(dev, "spi register failed\n");
562 		goto out_clk_disable;
563 	}
564 
565 	dev_info(dev, "at 0x%08x (irq %d, FIFOs size %d)\n",
566 		 r->start, irq, bs->fifo_size);
567 
568 	return 0;
569 
570 out_clk_disable:
571 	clk_disable_unprepare(clk);
572 out_err:
573 	spi_master_put(master);
574 	return ret;
575 }
576 
577 static int bcm63xx_spi_remove(struct platform_device *pdev)
578 {
579 	struct spi_master *master = platform_get_drvdata(pdev);
580 	struct bcm63xx_spi *bs = spi_master_get_devdata(master);
581 
582 	/* reset spi block */
583 	bcm_spi_writeb(bs, 0, SPI_INT_MASK);
584 
585 	/* HW shutdown */
586 	clk_disable_unprepare(bs->clk);
587 
588 	return 0;
589 }
590 
591 #ifdef CONFIG_PM_SLEEP
592 static int bcm63xx_spi_suspend(struct device *dev)
593 {
594 	struct spi_master *master = dev_get_drvdata(dev);
595 	struct bcm63xx_spi *bs = spi_master_get_devdata(master);
596 
597 	spi_master_suspend(master);
598 
599 	clk_disable_unprepare(bs->clk);
600 
601 	return 0;
602 }
603 
604 static int bcm63xx_spi_resume(struct device *dev)
605 {
606 	struct spi_master *master = dev_get_drvdata(dev);
607 	struct bcm63xx_spi *bs = spi_master_get_devdata(master);
608 	int ret;
609 
610 	ret = clk_prepare_enable(bs->clk);
611 	if (ret)
612 		return ret;
613 
614 	spi_master_resume(master);
615 
616 	return 0;
617 }
618 #endif
619 
620 static const struct dev_pm_ops bcm63xx_spi_pm_ops = {
621 	SET_SYSTEM_SLEEP_PM_OPS(bcm63xx_spi_suspend, bcm63xx_spi_resume)
622 };
623 
624 static struct platform_driver bcm63xx_spi_driver = {
625 	.driver = {
626 		.name	= "bcm63xx-spi",
627 		.pm	= &bcm63xx_spi_pm_ops,
628 	},
629 	.id_table	= bcm63xx_spi_dev_match,
630 	.probe		= bcm63xx_spi_probe,
631 	.remove		= bcm63xx_spi_remove,
632 };
633 
634 module_platform_driver(bcm63xx_spi_driver);
635 
636 MODULE_ALIAS("platform:bcm63xx_spi");
637 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
638 MODULE_AUTHOR("Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>");
639 MODULE_DESCRIPTION("Broadcom BCM63xx SPI Controller driver");
640 MODULE_LICENSE("GPL");
641