xref: /openbmc/linux/drivers/spi/spi-bcm63xx.c (revision 6abeae2a)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Broadcom BCM63xx SPI controller support
4  *
5  * Copyright (C) 2009-2012 Florian Fainelli <florian@openwrt.org>
6  * Copyright (C) 2010 Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/clk.h>
11 #include <linux/io.h>
12 #include <linux/module.h>
13 #include <linux/platform_device.h>
14 #include <linux/delay.h>
15 #include <linux/interrupt.h>
16 #include <linux/spi/spi.h>
17 #include <linux/completion.h>
18 #include <linux/err.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/of.h>
21 #include <linux/reset.h>
22 
23 /* BCM 6338/6348 SPI core */
24 #define SPI_6348_RSET_SIZE		64
25 #define SPI_6348_CMD			0x00	/* 16-bits register */
26 #define SPI_6348_INT_STATUS		0x02
27 #define SPI_6348_INT_MASK_ST		0x03
28 #define SPI_6348_INT_MASK		0x04
29 #define SPI_6348_ST			0x05
30 #define SPI_6348_CLK_CFG		0x06
31 #define SPI_6348_FILL_BYTE		0x07
32 #define SPI_6348_MSG_TAIL		0x09
33 #define SPI_6348_RX_TAIL		0x0b
34 #define SPI_6348_MSG_CTL		0x40	/* 8-bits register */
35 #define SPI_6348_MSG_CTL_WIDTH		8
36 #define SPI_6348_MSG_DATA		0x41
37 #define SPI_6348_MSG_DATA_SIZE		0x3f
38 #define SPI_6348_RX_DATA		0x80
39 #define SPI_6348_RX_DATA_SIZE		0x3f
40 
41 /* BCM 3368/6358/6262/6368 SPI core */
42 #define SPI_6358_RSET_SIZE		1804
43 #define SPI_6358_MSG_CTL		0x00	/* 16-bits register */
44 #define SPI_6358_MSG_CTL_WIDTH		16
45 #define SPI_6358_MSG_DATA		0x02
46 #define SPI_6358_MSG_DATA_SIZE		0x21e
47 #define SPI_6358_RX_DATA		0x400
48 #define SPI_6358_RX_DATA_SIZE		0x220
49 #define SPI_6358_CMD			0x700	/* 16-bits register */
50 #define SPI_6358_INT_STATUS		0x702
51 #define SPI_6358_INT_MASK_ST		0x703
52 #define SPI_6358_INT_MASK		0x704
53 #define SPI_6358_ST			0x705
54 #define SPI_6358_CLK_CFG		0x706
55 #define SPI_6358_FILL_BYTE		0x707
56 #define SPI_6358_MSG_TAIL		0x709
57 #define SPI_6358_RX_TAIL		0x70B
58 
59 /* Shared SPI definitions */
60 
61 /* Message configuration */
62 #define SPI_FD_RW			0x00
63 #define SPI_HD_W			0x01
64 #define SPI_HD_R			0x02
65 #define SPI_BYTE_CNT_SHIFT		0
66 #define SPI_6348_MSG_TYPE_SHIFT		6
67 #define SPI_6358_MSG_TYPE_SHIFT		14
68 
69 /* Command */
70 #define SPI_CMD_NOOP			0x00
71 #define SPI_CMD_SOFT_RESET		0x01
72 #define SPI_CMD_HARD_RESET		0x02
73 #define SPI_CMD_START_IMMEDIATE		0x03
74 #define SPI_CMD_COMMAND_SHIFT		0
75 #define SPI_CMD_COMMAND_MASK		0x000f
76 #define SPI_CMD_DEVICE_ID_SHIFT		4
77 #define SPI_CMD_PREPEND_BYTE_CNT_SHIFT	8
78 #define SPI_CMD_ONE_BYTE_SHIFT		11
79 #define SPI_CMD_ONE_WIRE_SHIFT		12
80 #define SPI_DEV_ID_0			0
81 #define SPI_DEV_ID_1			1
82 #define SPI_DEV_ID_2			2
83 #define SPI_DEV_ID_3			3
84 
85 /* Interrupt mask */
86 #define SPI_INTR_CMD_DONE		0x01
87 #define SPI_INTR_RX_OVERFLOW		0x02
88 #define SPI_INTR_TX_UNDERFLOW		0x04
89 #define SPI_INTR_TX_OVERFLOW		0x08
90 #define SPI_INTR_RX_UNDERFLOW		0x10
91 #define SPI_INTR_CLEAR_ALL		0x1f
92 
93 /* Status */
94 #define SPI_RX_EMPTY			0x02
95 #define SPI_CMD_BUSY			0x04
96 #define SPI_SERIAL_BUSY			0x08
97 
98 /* Clock configuration */
99 #define SPI_CLK_20MHZ			0x00
100 #define SPI_CLK_0_391MHZ		0x01
101 #define SPI_CLK_0_781MHZ		0x02	/* default */
102 #define SPI_CLK_1_563MHZ		0x03
103 #define SPI_CLK_3_125MHZ		0x04
104 #define SPI_CLK_6_250MHZ		0x05
105 #define SPI_CLK_12_50MHZ		0x06
106 #define SPI_CLK_MASK			0x07
107 #define SPI_SSOFFTIME_MASK		0x38
108 #define SPI_SSOFFTIME_SHIFT		3
109 #define SPI_BYTE_SWAP			0x80
110 
111 enum bcm63xx_regs_spi {
112 	SPI_CMD,
113 	SPI_INT_STATUS,
114 	SPI_INT_MASK_ST,
115 	SPI_INT_MASK,
116 	SPI_ST,
117 	SPI_CLK_CFG,
118 	SPI_FILL_BYTE,
119 	SPI_MSG_TAIL,
120 	SPI_RX_TAIL,
121 	SPI_MSG_CTL,
122 	SPI_MSG_DATA,
123 	SPI_RX_DATA,
124 	SPI_MSG_TYPE_SHIFT,
125 	SPI_MSG_CTL_WIDTH,
126 	SPI_MSG_DATA_SIZE,
127 };
128 
129 #define BCM63XX_SPI_MAX_PREPEND		15
130 
131 #define BCM63XX_SPI_MAX_CS		8
132 #define BCM63XX_SPI_BUS_NUM		0
133 
134 struct bcm63xx_spi {
135 	struct completion	done;
136 
137 	void __iomem		*regs;
138 	int			irq;
139 
140 	/* Platform data */
141 	const unsigned long	*reg_offsets;
142 	unsigned int		fifo_size;
143 	unsigned int		msg_type_shift;
144 	unsigned int		msg_ctl_width;
145 
146 	/* data iomem */
147 	u8 __iomem		*tx_io;
148 	const u8 __iomem	*rx_io;
149 
150 	struct clk		*clk;
151 	struct platform_device	*pdev;
152 };
153 
154 static inline u8 bcm_spi_readb(struct bcm63xx_spi *bs,
155 			       unsigned int offset)
156 {
157 	return readb(bs->regs + bs->reg_offsets[offset]);
158 }
159 
160 static inline u16 bcm_spi_readw(struct bcm63xx_spi *bs,
161 				unsigned int offset)
162 {
163 #ifdef CONFIG_CPU_BIG_ENDIAN
164 	return ioread16be(bs->regs + bs->reg_offsets[offset]);
165 #else
166 	return readw(bs->regs + bs->reg_offsets[offset]);
167 #endif
168 }
169 
170 static inline void bcm_spi_writeb(struct bcm63xx_spi *bs,
171 				  u8 value, unsigned int offset)
172 {
173 	writeb(value, bs->regs + bs->reg_offsets[offset]);
174 }
175 
176 static inline void bcm_spi_writew(struct bcm63xx_spi *bs,
177 				  u16 value, unsigned int offset)
178 {
179 #ifdef CONFIG_CPU_BIG_ENDIAN
180 	iowrite16be(value, bs->regs + bs->reg_offsets[offset]);
181 #else
182 	writew(value, bs->regs + bs->reg_offsets[offset]);
183 #endif
184 }
185 
186 static const unsigned int bcm63xx_spi_freq_table[SPI_CLK_MASK][2] = {
187 	{ 20000000, SPI_CLK_20MHZ },
188 	{ 12500000, SPI_CLK_12_50MHZ },
189 	{  6250000, SPI_CLK_6_250MHZ },
190 	{  3125000, SPI_CLK_3_125MHZ },
191 	{  1563000, SPI_CLK_1_563MHZ },
192 	{   781000, SPI_CLK_0_781MHZ },
193 	{   391000, SPI_CLK_0_391MHZ }
194 };
195 
196 static void bcm63xx_spi_setup_transfer(struct spi_device *spi,
197 				      struct spi_transfer *t)
198 {
199 	struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
200 	u8 clk_cfg, reg;
201 	int i;
202 
203 	/* Default to lowest clock configuration */
204 	clk_cfg = SPI_CLK_0_391MHZ;
205 
206 	/* Find the closest clock configuration */
207 	for (i = 0; i < SPI_CLK_MASK; i++) {
208 		if (t->speed_hz >= bcm63xx_spi_freq_table[i][0]) {
209 			clk_cfg = bcm63xx_spi_freq_table[i][1];
210 			break;
211 		}
212 	}
213 
214 	/* clear existing clock configuration bits of the register */
215 	reg = bcm_spi_readb(bs, SPI_CLK_CFG);
216 	reg &= ~SPI_CLK_MASK;
217 	reg |= clk_cfg;
218 
219 	bcm_spi_writeb(bs, reg, SPI_CLK_CFG);
220 	dev_dbg(&spi->dev, "Setting clock register to %02x (hz %d)\n",
221 		clk_cfg, t->speed_hz);
222 }
223 
224 /* the spi->mode bits understood by this driver: */
225 #define MODEBITS (SPI_CPOL | SPI_CPHA)
226 
227 static int bcm63xx_txrx_bufs(struct spi_device *spi, struct spi_transfer *first,
228 				unsigned int num_transfers)
229 {
230 	struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
231 	u16 msg_ctl;
232 	u16 cmd;
233 	unsigned int i, timeout = 0, prepend_len = 0, len = 0;
234 	struct spi_transfer *t = first;
235 	bool do_rx = false;
236 	bool do_tx = false;
237 
238 	/* Disable the CMD_DONE interrupt */
239 	bcm_spi_writeb(bs, 0, SPI_INT_MASK);
240 
241 	dev_dbg(&spi->dev, "txrx: tx %p, rx %p, len %d\n",
242 		t->tx_buf, t->rx_buf, t->len);
243 
244 	if (num_transfers > 1 && t->tx_buf && t->len <= BCM63XX_SPI_MAX_PREPEND)
245 		prepend_len = t->len;
246 
247 	/* prepare the buffer */
248 	for (i = 0; i < num_transfers; i++) {
249 		if (t->tx_buf) {
250 			do_tx = true;
251 			memcpy_toio(bs->tx_io + len, t->tx_buf, t->len);
252 
253 			/* don't prepend more than one tx */
254 			if (t != first)
255 				prepend_len = 0;
256 		}
257 
258 		if (t->rx_buf) {
259 			do_rx = true;
260 			/* prepend is half-duplex write only */
261 			if (t == first)
262 				prepend_len = 0;
263 		}
264 
265 		len += t->len;
266 
267 		t = list_entry(t->transfer_list.next, struct spi_transfer,
268 			       transfer_list);
269 	}
270 
271 	reinit_completion(&bs->done);
272 
273 	/* Fill in the Message control register */
274 	msg_ctl = (len << SPI_BYTE_CNT_SHIFT);
275 
276 	if (do_rx && do_tx && prepend_len == 0)
277 		msg_ctl |= (SPI_FD_RW << bs->msg_type_shift);
278 	else if (do_rx)
279 		msg_ctl |= (SPI_HD_R << bs->msg_type_shift);
280 	else if (do_tx)
281 		msg_ctl |= (SPI_HD_W << bs->msg_type_shift);
282 
283 	switch (bs->msg_ctl_width) {
284 	case 8:
285 		bcm_spi_writeb(bs, msg_ctl, SPI_MSG_CTL);
286 		break;
287 	case 16:
288 		bcm_spi_writew(bs, msg_ctl, SPI_MSG_CTL);
289 		break;
290 	}
291 
292 	/* Issue the transfer */
293 	cmd = SPI_CMD_START_IMMEDIATE;
294 	cmd |= (prepend_len << SPI_CMD_PREPEND_BYTE_CNT_SHIFT);
295 	cmd |= (spi->chip_select << SPI_CMD_DEVICE_ID_SHIFT);
296 	bcm_spi_writew(bs, cmd, SPI_CMD);
297 
298 	/* Enable the CMD_DONE interrupt */
299 	bcm_spi_writeb(bs, SPI_INTR_CMD_DONE, SPI_INT_MASK);
300 
301 	timeout = wait_for_completion_timeout(&bs->done, HZ);
302 	if (!timeout)
303 		return -ETIMEDOUT;
304 
305 	if (!do_rx)
306 		return 0;
307 
308 	len = 0;
309 	t = first;
310 	/* Read out all the data */
311 	for (i = 0; i < num_transfers; i++) {
312 		if (t->rx_buf)
313 			memcpy_fromio(t->rx_buf, bs->rx_io + len, t->len);
314 
315 		if (t != first || prepend_len == 0)
316 			len += t->len;
317 
318 		t = list_entry(t->transfer_list.next, struct spi_transfer,
319 			       transfer_list);
320 	}
321 
322 	return 0;
323 }
324 
325 static int bcm63xx_spi_transfer_one(struct spi_master *master,
326 					struct spi_message *m)
327 {
328 	struct bcm63xx_spi *bs = spi_master_get_devdata(master);
329 	struct spi_transfer *t, *first = NULL;
330 	struct spi_device *spi = m->spi;
331 	int status = 0;
332 	unsigned int n_transfers = 0, total_len = 0;
333 	bool can_use_prepend = false;
334 
335 	/*
336 	 * This SPI controller does not support keeping CS active after a
337 	 * transfer.
338 	 * Work around this by merging as many transfers we can into one big
339 	 * full-duplex transfers.
340 	 */
341 	list_for_each_entry(t, &m->transfers, transfer_list) {
342 		if (!first)
343 			first = t;
344 
345 		n_transfers++;
346 		total_len += t->len;
347 
348 		if (n_transfers == 2 && !first->rx_buf && !t->tx_buf &&
349 		    first->len <= BCM63XX_SPI_MAX_PREPEND)
350 			can_use_prepend = true;
351 		else if (can_use_prepend && t->tx_buf)
352 			can_use_prepend = false;
353 
354 		/* we can only transfer one fifo worth of data */
355 		if ((can_use_prepend &&
356 		     total_len > (bs->fifo_size + BCM63XX_SPI_MAX_PREPEND)) ||
357 		    (!can_use_prepend && total_len > bs->fifo_size)) {
358 			dev_err(&spi->dev, "unable to do transfers larger than FIFO size (%i > %i)\n",
359 				total_len, bs->fifo_size);
360 			status = -EINVAL;
361 			goto exit;
362 		}
363 
364 		/* all combined transfers have to have the same speed */
365 		if (t->speed_hz != first->speed_hz) {
366 			dev_err(&spi->dev, "unable to change speed between transfers\n");
367 			status = -EINVAL;
368 			goto exit;
369 		}
370 
371 		/* CS will be deasserted directly after transfer */
372 		if (t->delay_usecs || t->delay.value) {
373 			dev_err(&spi->dev, "unable to keep CS asserted after transfer\n");
374 			status = -EINVAL;
375 			goto exit;
376 		}
377 
378 		if (t->cs_change ||
379 		    list_is_last(&t->transfer_list, &m->transfers)) {
380 			/* configure adapter for a new transfer */
381 			bcm63xx_spi_setup_transfer(spi, first);
382 
383 			/* send the data */
384 			status = bcm63xx_txrx_bufs(spi, first, n_transfers);
385 			if (status)
386 				goto exit;
387 
388 			m->actual_length += total_len;
389 
390 			first = NULL;
391 			n_transfers = 0;
392 			total_len = 0;
393 			can_use_prepend = false;
394 		}
395 	}
396 exit:
397 	m->status = status;
398 	spi_finalize_current_message(master);
399 
400 	return 0;
401 }
402 
403 /* This driver supports single master mode only. Hence
404  * CMD_DONE is the only interrupt we care about
405  */
406 static irqreturn_t bcm63xx_spi_interrupt(int irq, void *dev_id)
407 {
408 	struct spi_master *master = (struct spi_master *)dev_id;
409 	struct bcm63xx_spi *bs = spi_master_get_devdata(master);
410 	u8 intr;
411 
412 	/* Read interupts and clear them immediately */
413 	intr = bcm_spi_readb(bs, SPI_INT_STATUS);
414 	bcm_spi_writeb(bs, SPI_INTR_CLEAR_ALL, SPI_INT_STATUS);
415 	bcm_spi_writeb(bs, 0, SPI_INT_MASK);
416 
417 	/* A transfer completed */
418 	if (intr & SPI_INTR_CMD_DONE)
419 		complete(&bs->done);
420 
421 	return IRQ_HANDLED;
422 }
423 
424 static size_t bcm63xx_spi_max_length(struct spi_device *spi)
425 {
426 	struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
427 
428 	return bs->fifo_size;
429 }
430 
431 static const unsigned long bcm6348_spi_reg_offsets[] = {
432 	[SPI_CMD]		= SPI_6348_CMD,
433 	[SPI_INT_STATUS]	= SPI_6348_INT_STATUS,
434 	[SPI_INT_MASK_ST]	= SPI_6348_INT_MASK_ST,
435 	[SPI_INT_MASK]		= SPI_6348_INT_MASK,
436 	[SPI_ST]		= SPI_6348_ST,
437 	[SPI_CLK_CFG]		= SPI_6348_CLK_CFG,
438 	[SPI_FILL_BYTE]		= SPI_6348_FILL_BYTE,
439 	[SPI_MSG_TAIL]		= SPI_6348_MSG_TAIL,
440 	[SPI_RX_TAIL]		= SPI_6348_RX_TAIL,
441 	[SPI_MSG_CTL]		= SPI_6348_MSG_CTL,
442 	[SPI_MSG_DATA]		= SPI_6348_MSG_DATA,
443 	[SPI_RX_DATA]		= SPI_6348_RX_DATA,
444 	[SPI_MSG_TYPE_SHIFT]	= SPI_6348_MSG_TYPE_SHIFT,
445 	[SPI_MSG_CTL_WIDTH]	= SPI_6348_MSG_CTL_WIDTH,
446 	[SPI_MSG_DATA_SIZE]	= SPI_6348_MSG_DATA_SIZE,
447 };
448 
449 static const unsigned long bcm6358_spi_reg_offsets[] = {
450 	[SPI_CMD]		= SPI_6358_CMD,
451 	[SPI_INT_STATUS]	= SPI_6358_INT_STATUS,
452 	[SPI_INT_MASK_ST]	= SPI_6358_INT_MASK_ST,
453 	[SPI_INT_MASK]		= SPI_6358_INT_MASK,
454 	[SPI_ST]		= SPI_6358_ST,
455 	[SPI_CLK_CFG]		= SPI_6358_CLK_CFG,
456 	[SPI_FILL_BYTE]		= SPI_6358_FILL_BYTE,
457 	[SPI_MSG_TAIL]		= SPI_6358_MSG_TAIL,
458 	[SPI_RX_TAIL]		= SPI_6358_RX_TAIL,
459 	[SPI_MSG_CTL]		= SPI_6358_MSG_CTL,
460 	[SPI_MSG_DATA]		= SPI_6358_MSG_DATA,
461 	[SPI_RX_DATA]		= SPI_6358_RX_DATA,
462 	[SPI_MSG_TYPE_SHIFT]	= SPI_6358_MSG_TYPE_SHIFT,
463 	[SPI_MSG_CTL_WIDTH]	= SPI_6358_MSG_CTL_WIDTH,
464 	[SPI_MSG_DATA_SIZE]	= SPI_6358_MSG_DATA_SIZE,
465 };
466 
467 static const struct platform_device_id bcm63xx_spi_dev_match[] = {
468 	{
469 		.name = "bcm6348-spi",
470 		.driver_data = (unsigned long)bcm6348_spi_reg_offsets,
471 	},
472 	{
473 		.name = "bcm6358-spi",
474 		.driver_data = (unsigned long)bcm6358_spi_reg_offsets,
475 	},
476 	{
477 	},
478 };
479 
480 static const struct of_device_id bcm63xx_spi_of_match[] = {
481 	{ .compatible = "brcm,bcm6348-spi", .data = &bcm6348_spi_reg_offsets },
482 	{ .compatible = "brcm,bcm6358-spi", .data = &bcm6358_spi_reg_offsets },
483 	{ },
484 };
485 
486 static int bcm63xx_spi_probe(struct platform_device *pdev)
487 {
488 	struct resource *r;
489 	const unsigned long *bcm63xx_spireg;
490 	struct device *dev = &pdev->dev;
491 	int irq, bus_num;
492 	struct spi_master *master;
493 	struct clk *clk;
494 	struct bcm63xx_spi *bs;
495 	int ret;
496 	u32 num_cs = BCM63XX_SPI_MAX_CS;
497 	struct reset_control *reset;
498 
499 	if (dev->of_node) {
500 		const struct of_device_id *match;
501 
502 		match = of_match_node(bcm63xx_spi_of_match, dev->of_node);
503 		if (!match)
504 			return -EINVAL;
505 		bcm63xx_spireg = match->data;
506 
507 		of_property_read_u32(dev->of_node, "num-cs", &num_cs);
508 		if (num_cs > BCM63XX_SPI_MAX_CS) {
509 			dev_warn(dev, "unsupported number of cs (%i), reducing to 8\n",
510 				 num_cs);
511 			num_cs = BCM63XX_SPI_MAX_CS;
512 		}
513 
514 		bus_num = -1;
515 	} else if (pdev->id_entry->driver_data) {
516 		const struct platform_device_id *match = pdev->id_entry;
517 
518 		bcm63xx_spireg = (const unsigned long *)match->driver_data;
519 		bus_num = BCM63XX_SPI_BUS_NUM;
520 	} else {
521 		return -EINVAL;
522 	}
523 
524 	irq = platform_get_irq(pdev, 0);
525 	if (irq < 0)
526 		return irq;
527 
528 	clk = devm_clk_get(dev, "spi");
529 	if (IS_ERR(clk)) {
530 		dev_err(dev, "no clock for device\n");
531 		return PTR_ERR(clk);
532 	}
533 
534 	reset = devm_reset_control_get_optional_exclusive(dev, NULL);
535 	if (IS_ERR(reset))
536 		return PTR_ERR(reset);
537 
538 	master = spi_alloc_master(dev, sizeof(*bs));
539 	if (!master) {
540 		dev_err(dev, "out of memory\n");
541 		return -ENOMEM;
542 	}
543 
544 	bs = spi_master_get_devdata(master);
545 	init_completion(&bs->done);
546 
547 	platform_set_drvdata(pdev, master);
548 	bs->pdev = pdev;
549 
550 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
551 	bs->regs = devm_ioremap_resource(&pdev->dev, r);
552 	if (IS_ERR(bs->regs)) {
553 		ret = PTR_ERR(bs->regs);
554 		goto out_err;
555 	}
556 
557 	bs->irq = irq;
558 	bs->clk = clk;
559 	bs->reg_offsets = bcm63xx_spireg;
560 	bs->fifo_size = bs->reg_offsets[SPI_MSG_DATA_SIZE];
561 
562 	ret = devm_request_irq(&pdev->dev, irq, bcm63xx_spi_interrupt, 0,
563 							pdev->name, master);
564 	if (ret) {
565 		dev_err(dev, "unable to request irq\n");
566 		goto out_err;
567 	}
568 
569 	master->dev.of_node = dev->of_node;
570 	master->bus_num = bus_num;
571 	master->num_chipselect = num_cs;
572 	master->transfer_one_message = bcm63xx_spi_transfer_one;
573 	master->mode_bits = MODEBITS;
574 	master->bits_per_word_mask = SPI_BPW_MASK(8);
575 	master->max_transfer_size = bcm63xx_spi_max_length;
576 	master->max_message_size = bcm63xx_spi_max_length;
577 	master->auto_runtime_pm = true;
578 	bs->msg_type_shift = bs->reg_offsets[SPI_MSG_TYPE_SHIFT];
579 	bs->msg_ctl_width = bs->reg_offsets[SPI_MSG_CTL_WIDTH];
580 	bs->tx_io = (u8 *)(bs->regs + bs->reg_offsets[SPI_MSG_DATA]);
581 	bs->rx_io = (const u8 *)(bs->regs + bs->reg_offsets[SPI_RX_DATA]);
582 
583 	/* Initialize hardware */
584 	ret = clk_prepare_enable(bs->clk);
585 	if (ret)
586 		goto out_err;
587 
588 	ret = reset_control_reset(reset);
589 	if (ret) {
590 		dev_err(dev, "unable to reset device: %d\n", ret);
591 		goto out_clk_disable;
592 	}
593 
594 	bcm_spi_writeb(bs, SPI_INTR_CLEAR_ALL, SPI_INT_STATUS);
595 
596 	/* register and we are done */
597 	ret = devm_spi_register_master(dev, master);
598 	if (ret) {
599 		dev_err(dev, "spi register failed\n");
600 		goto out_clk_disable;
601 	}
602 
603 	dev_info(dev, "at %pr (irq %d, FIFOs size %d)\n",
604 		 r, irq, bs->fifo_size);
605 
606 	return 0;
607 
608 out_clk_disable:
609 	clk_disable_unprepare(clk);
610 out_err:
611 	spi_master_put(master);
612 	return ret;
613 }
614 
615 static int bcm63xx_spi_remove(struct platform_device *pdev)
616 {
617 	struct spi_master *master = platform_get_drvdata(pdev);
618 	struct bcm63xx_spi *bs = spi_master_get_devdata(master);
619 
620 	/* reset spi block */
621 	bcm_spi_writeb(bs, 0, SPI_INT_MASK);
622 
623 	/* HW shutdown */
624 	clk_disable_unprepare(bs->clk);
625 
626 	return 0;
627 }
628 
629 #ifdef CONFIG_PM_SLEEP
630 static int bcm63xx_spi_suspend(struct device *dev)
631 {
632 	struct spi_master *master = dev_get_drvdata(dev);
633 	struct bcm63xx_spi *bs = spi_master_get_devdata(master);
634 
635 	spi_master_suspend(master);
636 
637 	clk_disable_unprepare(bs->clk);
638 
639 	return 0;
640 }
641 
642 static int bcm63xx_spi_resume(struct device *dev)
643 {
644 	struct spi_master *master = dev_get_drvdata(dev);
645 	struct bcm63xx_spi *bs = spi_master_get_devdata(master);
646 	int ret;
647 
648 	ret = clk_prepare_enable(bs->clk);
649 	if (ret)
650 		return ret;
651 
652 	spi_master_resume(master);
653 
654 	return 0;
655 }
656 #endif
657 
658 static const struct dev_pm_ops bcm63xx_spi_pm_ops = {
659 	SET_SYSTEM_SLEEP_PM_OPS(bcm63xx_spi_suspend, bcm63xx_spi_resume)
660 };
661 
662 static struct platform_driver bcm63xx_spi_driver = {
663 	.driver = {
664 		.name	= "bcm63xx-spi",
665 		.pm	= &bcm63xx_spi_pm_ops,
666 		.of_match_table = bcm63xx_spi_of_match,
667 	},
668 	.id_table	= bcm63xx_spi_dev_match,
669 	.probe		= bcm63xx_spi_probe,
670 	.remove		= bcm63xx_spi_remove,
671 };
672 
673 module_platform_driver(bcm63xx_spi_driver);
674 
675 MODULE_ALIAS("platform:bcm63xx_spi");
676 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
677 MODULE_AUTHOR("Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>");
678 MODULE_DESCRIPTION("Broadcom BCM63xx SPI Controller driver");
679 MODULE_LICENSE("GPL");
680