xref: /openbmc/linux/drivers/spi/spi-imx.c (revision 249592bf)
1 // SPDX-License-Identifier: GPL-2.0+
2 // Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
3 // Copyright (C) 2008 Juergen Beisert
4 
5 #include <linux/clk.h>
6 #include <linux/completion.h>
7 #include <linux/delay.h>
8 #include <linux/dmaengine.h>
9 #include <linux/dma-mapping.h>
10 #include <linux/err.h>
11 #include <linux/interrupt.h>
12 #include <linux/io.h>
13 #include <linux/irq.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/pinctrl/consumer.h>
17 #include <linux/platform_device.h>
18 #include <linux/pm_runtime.h>
19 #include <linux/slab.h>
20 #include <linux/spi/spi.h>
21 #include <linux/spi/spi_bitbang.h>
22 #include <linux/types.h>
23 #include <linux/of.h>
24 #include <linux/of_device.h>
25 #include <linux/property.h>
26 
27 #include <linux/platform_data/dma-imx.h>
28 
29 #define DRIVER_NAME "spi_imx"
30 
31 static bool use_dma = true;
32 module_param(use_dma, bool, 0644);
33 MODULE_PARM_DESC(use_dma, "Enable usage of DMA when available (default)");
34 
35 #define MXC_RPM_TIMEOUT		2000 /* 2000ms */
36 
37 #define MXC_CSPIRXDATA		0x00
38 #define MXC_CSPITXDATA		0x04
39 #define MXC_CSPICTRL		0x08
40 #define MXC_CSPIINT		0x0c
41 #define MXC_RESET		0x1c
42 
43 /* generic defines to abstract from the different register layouts */
44 #define MXC_INT_RR	(1 << 0) /* Receive data ready interrupt */
45 #define MXC_INT_TE	(1 << 1) /* Transmit FIFO empty interrupt */
46 #define MXC_INT_RDR	BIT(4) /* Receive date threshold interrupt */
47 
48 /* The maximum bytes that a sdma BD can transfer. */
49 #define MAX_SDMA_BD_BYTES (1 << 15)
50 #define MX51_ECSPI_CTRL_MAX_BURST	512
51 /* The maximum bytes that IMX53_ECSPI can transfer in slave mode.*/
52 #define MX53_MAX_TRANSFER_BYTES		512
53 
54 enum spi_imx_devtype {
55 	IMX1_CSPI,
56 	IMX21_CSPI,
57 	IMX27_CSPI,
58 	IMX31_CSPI,
59 	IMX35_CSPI,	/* CSPI on all i.mx except above */
60 	IMX51_ECSPI,	/* ECSPI on i.mx51 */
61 	IMX53_ECSPI,	/* ECSPI on i.mx53 and later */
62 };
63 
64 struct spi_imx_data;
65 
66 struct spi_imx_devtype_data {
67 	void (*intctrl)(struct spi_imx_data *, int);
68 	int (*prepare_message)(struct spi_imx_data *, struct spi_message *);
69 	int (*prepare_transfer)(struct spi_imx_data *, struct spi_device *);
70 	void (*trigger)(struct spi_imx_data *);
71 	int (*rx_available)(struct spi_imx_data *);
72 	void (*reset)(struct spi_imx_data *);
73 	void (*setup_wml)(struct spi_imx_data *);
74 	void (*disable)(struct spi_imx_data *);
75 	void (*disable_dma)(struct spi_imx_data *);
76 	bool has_dmamode;
77 	bool has_slavemode;
78 	unsigned int fifo_size;
79 	bool dynamic_burst;
80 	enum spi_imx_devtype devtype;
81 };
82 
83 struct spi_imx_data {
84 	struct spi_bitbang bitbang;
85 	struct device *dev;
86 
87 	struct completion xfer_done;
88 	void __iomem *base;
89 	unsigned long base_phys;
90 
91 	struct clk *clk_per;
92 	struct clk *clk_ipg;
93 	unsigned long spi_clk;
94 	unsigned int spi_bus_clk;
95 
96 	unsigned int bits_per_word;
97 	unsigned int spi_drctl;
98 
99 	unsigned int count, remainder;
100 	void (*tx)(struct spi_imx_data *);
101 	void (*rx)(struct spi_imx_data *);
102 	void *rx_buf;
103 	const void *tx_buf;
104 	unsigned int txfifo; /* number of words pushed in tx FIFO */
105 	unsigned int dynamic_burst;
106 
107 	/* Slave mode */
108 	bool slave_mode;
109 	bool slave_aborted;
110 	unsigned int slave_burst;
111 
112 	/* DMA */
113 	bool usedma;
114 	u32 wml;
115 	struct completion dma_rx_completion;
116 	struct completion dma_tx_completion;
117 
118 	const struct spi_imx_devtype_data *devtype_data;
119 };
120 
121 static inline int is_imx27_cspi(struct spi_imx_data *d)
122 {
123 	return d->devtype_data->devtype == IMX27_CSPI;
124 }
125 
126 static inline int is_imx35_cspi(struct spi_imx_data *d)
127 {
128 	return d->devtype_data->devtype == IMX35_CSPI;
129 }
130 
131 static inline int is_imx51_ecspi(struct spi_imx_data *d)
132 {
133 	return d->devtype_data->devtype == IMX51_ECSPI;
134 }
135 
136 static inline int is_imx53_ecspi(struct spi_imx_data *d)
137 {
138 	return d->devtype_data->devtype == IMX53_ECSPI;
139 }
140 
141 #define MXC_SPI_BUF_RX(type)						\
142 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
143 {									\
144 	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
145 									\
146 	if (spi_imx->rx_buf) {						\
147 		*(type *)spi_imx->rx_buf = val;				\
148 		spi_imx->rx_buf += sizeof(type);			\
149 	}								\
150 									\
151 	spi_imx->remainder -= sizeof(type);				\
152 }
153 
154 #define MXC_SPI_BUF_TX(type)						\
155 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
156 {									\
157 	type val = 0;							\
158 									\
159 	if (spi_imx->tx_buf) {						\
160 		val = *(type *)spi_imx->tx_buf;				\
161 		spi_imx->tx_buf += sizeof(type);			\
162 	}								\
163 									\
164 	spi_imx->count -= sizeof(type);					\
165 									\
166 	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
167 }
168 
169 MXC_SPI_BUF_RX(u8)
170 MXC_SPI_BUF_TX(u8)
171 MXC_SPI_BUF_RX(u16)
172 MXC_SPI_BUF_TX(u16)
173 MXC_SPI_BUF_RX(u32)
174 MXC_SPI_BUF_TX(u32)
175 
176 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
177  * (which is currently not the case in this driver)
178  */
179 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
180 	256, 384, 512, 768, 1024};
181 
182 /* MX21, MX27 */
183 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
184 		unsigned int fspi, unsigned int max, unsigned int *fres)
185 {
186 	int i;
187 
188 	for (i = 2; i < max; i++)
189 		if (fspi * mxc_clkdivs[i] >= fin)
190 			break;
191 
192 	*fres = fin / mxc_clkdivs[i];
193 	return i;
194 }
195 
196 /* MX1, MX31, MX35, MX51 CSPI */
197 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
198 		unsigned int fspi, unsigned int *fres)
199 {
200 	int i, div = 4;
201 
202 	for (i = 0; i < 7; i++) {
203 		if (fspi * div >= fin)
204 			goto out;
205 		div <<= 1;
206 	}
207 
208 out:
209 	*fres = fin / div;
210 	return i;
211 }
212 
213 static int spi_imx_bytes_per_word(const int bits_per_word)
214 {
215 	if (bits_per_word <= 8)
216 		return 1;
217 	else if (bits_per_word <= 16)
218 		return 2;
219 	else
220 		return 4;
221 }
222 
223 static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
224 			 struct spi_transfer *transfer)
225 {
226 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
227 
228 	if (!use_dma || master->fallback)
229 		return false;
230 
231 	if (!master->dma_rx)
232 		return false;
233 
234 	if (spi_imx->slave_mode)
235 		return false;
236 
237 	if (transfer->len < spi_imx->devtype_data->fifo_size)
238 		return false;
239 
240 	spi_imx->dynamic_burst = 0;
241 
242 	return true;
243 }
244 
245 #define MX51_ECSPI_CTRL		0x08
246 #define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
247 #define MX51_ECSPI_CTRL_XCH		(1 <<  2)
248 #define MX51_ECSPI_CTRL_SMC		(1 << 3)
249 #define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
250 #define MX51_ECSPI_CTRL_DRCTL(drctl)	((drctl) << 16)
251 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
252 #define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
253 #define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
254 #define MX51_ECSPI_CTRL_BL_OFFSET	20
255 #define MX51_ECSPI_CTRL_BL_MASK		(0xfff << 20)
256 
257 #define MX51_ECSPI_CONFIG	0x0c
258 #define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
259 #define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
260 #define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
261 #define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
262 #define MX51_ECSPI_CONFIG_SCLKCTL(cs)	(1 << ((cs) + 20))
263 
264 #define MX51_ECSPI_INT		0x10
265 #define MX51_ECSPI_INT_TEEN		(1 <<  0)
266 #define MX51_ECSPI_INT_RREN		(1 <<  3)
267 #define MX51_ECSPI_INT_RDREN		(1 <<  4)
268 
269 #define MX51_ECSPI_DMA		0x14
270 #define MX51_ECSPI_DMA_TX_WML(wml)	((wml) & 0x3f)
271 #define MX51_ECSPI_DMA_RX_WML(wml)	(((wml) & 0x3f) << 16)
272 #define MX51_ECSPI_DMA_RXT_WML(wml)	(((wml) & 0x3f) << 24)
273 
274 #define MX51_ECSPI_DMA_TEDEN		(1 << 7)
275 #define MX51_ECSPI_DMA_RXDEN		(1 << 23)
276 #define MX51_ECSPI_DMA_RXTDEN		(1 << 31)
277 
278 #define MX51_ECSPI_STAT		0x18
279 #define MX51_ECSPI_STAT_RR		(1 <<  3)
280 
281 #define MX51_ECSPI_TESTREG	0x20
282 #define MX51_ECSPI_TESTREG_LBC	BIT(31)
283 
284 static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
285 {
286 	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
287 #ifdef __LITTLE_ENDIAN
288 	unsigned int bytes_per_word;
289 #endif
290 
291 	if (spi_imx->rx_buf) {
292 #ifdef __LITTLE_ENDIAN
293 		bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
294 		if (bytes_per_word == 1)
295 			val = cpu_to_be32(val);
296 		else if (bytes_per_word == 2)
297 			val = (val << 16) | (val >> 16);
298 #endif
299 		*(u32 *)spi_imx->rx_buf = val;
300 		spi_imx->rx_buf += sizeof(u32);
301 	}
302 
303 	spi_imx->remainder -= sizeof(u32);
304 }
305 
306 static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
307 {
308 	int unaligned;
309 	u32 val;
310 
311 	unaligned = spi_imx->remainder % 4;
312 
313 	if (!unaligned) {
314 		spi_imx_buf_rx_swap_u32(spi_imx);
315 		return;
316 	}
317 
318 	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
319 		spi_imx_buf_rx_u16(spi_imx);
320 		return;
321 	}
322 
323 	val = readl(spi_imx->base + MXC_CSPIRXDATA);
324 
325 	while (unaligned--) {
326 		if (spi_imx->rx_buf) {
327 			*(u8 *)spi_imx->rx_buf = (val >> (8 * unaligned)) & 0xff;
328 			spi_imx->rx_buf++;
329 		}
330 		spi_imx->remainder--;
331 	}
332 }
333 
334 static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
335 {
336 	u32 val = 0;
337 #ifdef __LITTLE_ENDIAN
338 	unsigned int bytes_per_word;
339 #endif
340 
341 	if (spi_imx->tx_buf) {
342 		val = *(u32 *)spi_imx->tx_buf;
343 		spi_imx->tx_buf += sizeof(u32);
344 	}
345 
346 	spi_imx->count -= sizeof(u32);
347 #ifdef __LITTLE_ENDIAN
348 	bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
349 
350 	if (bytes_per_word == 1)
351 		val = cpu_to_be32(val);
352 	else if (bytes_per_word == 2)
353 		val = (val << 16) | (val >> 16);
354 #endif
355 	writel(val, spi_imx->base + MXC_CSPITXDATA);
356 }
357 
358 static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
359 {
360 	int unaligned;
361 	u32 val = 0;
362 
363 	unaligned = spi_imx->count % 4;
364 
365 	if (!unaligned) {
366 		spi_imx_buf_tx_swap_u32(spi_imx);
367 		return;
368 	}
369 
370 	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
371 		spi_imx_buf_tx_u16(spi_imx);
372 		return;
373 	}
374 
375 	while (unaligned--) {
376 		if (spi_imx->tx_buf) {
377 			val |= *(u8 *)spi_imx->tx_buf << (8 * unaligned);
378 			spi_imx->tx_buf++;
379 		}
380 		spi_imx->count--;
381 	}
382 
383 	writel(val, spi_imx->base + MXC_CSPITXDATA);
384 }
385 
386 static void mx53_ecspi_rx_slave(struct spi_imx_data *spi_imx)
387 {
388 	u32 val = be32_to_cpu(readl(spi_imx->base + MXC_CSPIRXDATA));
389 
390 	if (spi_imx->rx_buf) {
391 		int n_bytes = spi_imx->slave_burst % sizeof(val);
392 
393 		if (!n_bytes)
394 			n_bytes = sizeof(val);
395 
396 		memcpy(spi_imx->rx_buf,
397 		       ((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
398 
399 		spi_imx->rx_buf += n_bytes;
400 		spi_imx->slave_burst -= n_bytes;
401 	}
402 
403 	spi_imx->remainder -= sizeof(u32);
404 }
405 
406 static void mx53_ecspi_tx_slave(struct spi_imx_data *spi_imx)
407 {
408 	u32 val = 0;
409 	int n_bytes = spi_imx->count % sizeof(val);
410 
411 	if (!n_bytes)
412 		n_bytes = sizeof(val);
413 
414 	if (spi_imx->tx_buf) {
415 		memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
416 		       spi_imx->tx_buf, n_bytes);
417 		val = cpu_to_be32(val);
418 		spi_imx->tx_buf += n_bytes;
419 	}
420 
421 	spi_imx->count -= n_bytes;
422 
423 	writel(val, spi_imx->base + MXC_CSPITXDATA);
424 }
425 
426 /* MX51 eCSPI */
427 static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
428 				      unsigned int fspi, unsigned int *fres)
429 {
430 	/*
431 	 * there are two 4-bit dividers, the pre-divider divides by
432 	 * $pre, the post-divider by 2^$post
433 	 */
434 	unsigned int pre, post;
435 	unsigned int fin = spi_imx->spi_clk;
436 
437 	if (unlikely(fspi > fin))
438 		return 0;
439 
440 	post = fls(fin) - fls(fspi);
441 	if (fin > fspi << post)
442 		post++;
443 
444 	/* now we have: (fin <= fspi << post) with post being minimal */
445 
446 	post = max(4U, post) - 4;
447 	if (unlikely(post > 0xf)) {
448 		dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
449 				fspi, fin);
450 		return 0xff;
451 	}
452 
453 	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
454 
455 	dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
456 			__func__, fin, fspi, post, pre);
457 
458 	/* Resulting frequency for the SCLK line. */
459 	*fres = (fin / (pre + 1)) >> post;
460 
461 	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
462 		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
463 }
464 
465 static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
466 {
467 	unsigned val = 0;
468 
469 	if (enable & MXC_INT_TE)
470 		val |= MX51_ECSPI_INT_TEEN;
471 
472 	if (enable & MXC_INT_RR)
473 		val |= MX51_ECSPI_INT_RREN;
474 
475 	if (enable & MXC_INT_RDR)
476 		val |= MX51_ECSPI_INT_RDREN;
477 
478 	writel(val, spi_imx->base + MX51_ECSPI_INT);
479 }
480 
481 static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
482 {
483 	u32 reg;
484 
485 	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
486 	reg |= MX51_ECSPI_CTRL_XCH;
487 	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
488 }
489 
490 static void mx51_disable_dma(struct spi_imx_data *spi_imx)
491 {
492 	writel(0, spi_imx->base + MX51_ECSPI_DMA);
493 }
494 
495 static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
496 {
497 	u32 ctrl;
498 
499 	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
500 	ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
501 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
502 }
503 
504 static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
505 				      struct spi_message *msg)
506 {
507 	struct spi_device *spi = msg->spi;
508 	u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
509 	u32 testreg;
510 	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
511 
512 	/* set Master or Slave mode */
513 	if (spi_imx->slave_mode)
514 		ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
515 	else
516 		ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
517 
518 	/*
519 	 * Enable SPI_RDY handling (falling edge/level triggered).
520 	 */
521 	if (spi->mode & SPI_READY)
522 		ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
523 
524 	/* set chip select to use */
525 	ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
526 
527 	/*
528 	 * The ctrl register must be written first, with the EN bit set other
529 	 * registers must not be written to.
530 	 */
531 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
532 
533 	testreg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
534 	if (spi->mode & SPI_LOOP)
535 		testreg |= MX51_ECSPI_TESTREG_LBC;
536 	else
537 		testreg &= ~MX51_ECSPI_TESTREG_LBC;
538 	writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
539 
540 	/*
541 	 * eCSPI burst completion by Chip Select signal in Slave mode
542 	 * is not functional for imx53 Soc, config SPI burst completed when
543 	 * BURST_LENGTH + 1 bits are received
544 	 */
545 	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
546 		cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
547 	else
548 		cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
549 
550 	if (spi->mode & SPI_CPHA)
551 		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
552 	else
553 		cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
554 
555 	if (spi->mode & SPI_CPOL) {
556 		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
557 		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
558 	} else {
559 		cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
560 		cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
561 	}
562 
563 	if (spi->mode & SPI_CS_HIGH)
564 		cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
565 	else
566 		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
567 
568 	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
569 
570 	return 0;
571 }
572 
573 static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
574 				       struct spi_device *spi)
575 {
576 	u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
577 	u32 clk, delay;
578 
579 	/* Clear BL field and set the right value */
580 	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
581 	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
582 		ctrl |= (spi_imx->slave_burst * 8 - 1)
583 			<< MX51_ECSPI_CTRL_BL_OFFSET;
584 	else
585 		ctrl |= (spi_imx->bits_per_word - 1)
586 			<< MX51_ECSPI_CTRL_BL_OFFSET;
587 
588 	/* set clock speed */
589 	ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
590 		  0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
591 	ctrl |= mx51_ecspi_clkdiv(spi_imx, spi_imx->spi_bus_clk, &clk);
592 	spi_imx->spi_bus_clk = clk;
593 
594 	if (spi_imx->usedma)
595 		ctrl |= MX51_ECSPI_CTRL_SMC;
596 
597 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
598 
599 	/*
600 	 * Wait until the changes in the configuration register CONFIGREG
601 	 * propagate into the hardware. It takes exactly one tick of the
602 	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
603 	 * effect of the delay it takes for the hardware to apply changes
604 	 * is noticable if the SCLK clock run very slow. In such a case, if
605 	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
606 	 * be asserted before the SCLK polarity changes, which would disrupt
607 	 * the SPI communication as the device on the other end would consider
608 	 * the change of SCLK polarity as a clock tick already.
609 	 */
610 	delay = (2 * 1000000) / clk;
611 	if (likely(delay < 10))	/* SCLK is faster than 100 kHz */
612 		udelay(delay);
613 	else			/* SCLK is _very_ slow */
614 		usleep_range(delay, delay + 10);
615 
616 	return 0;
617 }
618 
619 static void mx51_setup_wml(struct spi_imx_data *spi_imx)
620 {
621 	/*
622 	 * Configure the DMA register: setup the watermark
623 	 * and enable DMA request.
624 	 */
625 	writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) |
626 		MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
627 		MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
628 		MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
629 		MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
630 }
631 
632 static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
633 {
634 	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
635 }
636 
637 static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
638 {
639 	/* drain receive buffer */
640 	while (mx51_ecspi_rx_available(spi_imx))
641 		readl(spi_imx->base + MXC_CSPIRXDATA);
642 }
643 
644 #define MX31_INTREG_TEEN	(1 << 0)
645 #define MX31_INTREG_RREN	(1 << 3)
646 
647 #define MX31_CSPICTRL_ENABLE	(1 << 0)
648 #define MX31_CSPICTRL_MASTER	(1 << 1)
649 #define MX31_CSPICTRL_XCH	(1 << 2)
650 #define MX31_CSPICTRL_SMC	(1 << 3)
651 #define MX31_CSPICTRL_POL	(1 << 4)
652 #define MX31_CSPICTRL_PHA	(1 << 5)
653 #define MX31_CSPICTRL_SSCTL	(1 << 6)
654 #define MX31_CSPICTRL_SSPOL	(1 << 7)
655 #define MX31_CSPICTRL_BC_SHIFT	8
656 #define MX35_CSPICTRL_BL_SHIFT	20
657 #define MX31_CSPICTRL_CS_SHIFT	24
658 #define MX35_CSPICTRL_CS_SHIFT	12
659 #define MX31_CSPICTRL_DR_SHIFT	16
660 
661 #define MX31_CSPI_DMAREG	0x10
662 #define MX31_DMAREG_RH_DEN	(1<<4)
663 #define MX31_DMAREG_TH_DEN	(1<<1)
664 
665 #define MX31_CSPISTATUS		0x14
666 #define MX31_STATUS_RR		(1 << 3)
667 
668 #define MX31_CSPI_TESTREG	0x1C
669 #define MX31_TEST_LBC		(1 << 14)
670 
671 /* These functions also work for the i.MX35, but be aware that
672  * the i.MX35 has a slightly different register layout for bits
673  * we do not use here.
674  */
675 static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
676 {
677 	unsigned int val = 0;
678 
679 	if (enable & MXC_INT_TE)
680 		val |= MX31_INTREG_TEEN;
681 	if (enable & MXC_INT_RR)
682 		val |= MX31_INTREG_RREN;
683 
684 	writel(val, spi_imx->base + MXC_CSPIINT);
685 }
686 
687 static void mx31_trigger(struct spi_imx_data *spi_imx)
688 {
689 	unsigned int reg;
690 
691 	reg = readl(spi_imx->base + MXC_CSPICTRL);
692 	reg |= MX31_CSPICTRL_XCH;
693 	writel(reg, spi_imx->base + MXC_CSPICTRL);
694 }
695 
696 static int mx31_prepare_message(struct spi_imx_data *spi_imx,
697 				struct spi_message *msg)
698 {
699 	return 0;
700 }
701 
702 static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
703 				 struct spi_device *spi)
704 {
705 	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
706 	unsigned int clk;
707 
708 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
709 		MX31_CSPICTRL_DR_SHIFT;
710 	spi_imx->spi_bus_clk = clk;
711 
712 	if (is_imx35_cspi(spi_imx)) {
713 		reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
714 		reg |= MX31_CSPICTRL_SSCTL;
715 	} else {
716 		reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
717 	}
718 
719 	if (spi->mode & SPI_CPHA)
720 		reg |= MX31_CSPICTRL_PHA;
721 	if (spi->mode & SPI_CPOL)
722 		reg |= MX31_CSPICTRL_POL;
723 	if (spi->mode & SPI_CS_HIGH)
724 		reg |= MX31_CSPICTRL_SSPOL;
725 	if (!spi->cs_gpiod)
726 		reg |= (spi->chip_select) <<
727 			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
728 						  MX31_CSPICTRL_CS_SHIFT);
729 
730 	if (spi_imx->usedma)
731 		reg |= MX31_CSPICTRL_SMC;
732 
733 	writel(reg, spi_imx->base + MXC_CSPICTRL);
734 
735 	reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
736 	if (spi->mode & SPI_LOOP)
737 		reg |= MX31_TEST_LBC;
738 	else
739 		reg &= ~MX31_TEST_LBC;
740 	writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
741 
742 	if (spi_imx->usedma) {
743 		/*
744 		 * configure DMA requests when RXFIFO is half full and
745 		 * when TXFIFO is half empty
746 		 */
747 		writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
748 			spi_imx->base + MX31_CSPI_DMAREG);
749 	}
750 
751 	return 0;
752 }
753 
754 static int mx31_rx_available(struct spi_imx_data *spi_imx)
755 {
756 	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
757 }
758 
759 static void mx31_reset(struct spi_imx_data *spi_imx)
760 {
761 	/* drain receive buffer */
762 	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
763 		readl(spi_imx->base + MXC_CSPIRXDATA);
764 }
765 
766 #define MX21_INTREG_RR		(1 << 4)
767 #define MX21_INTREG_TEEN	(1 << 9)
768 #define MX21_INTREG_RREN	(1 << 13)
769 
770 #define MX21_CSPICTRL_POL	(1 << 5)
771 #define MX21_CSPICTRL_PHA	(1 << 6)
772 #define MX21_CSPICTRL_SSPOL	(1 << 8)
773 #define MX21_CSPICTRL_XCH	(1 << 9)
774 #define MX21_CSPICTRL_ENABLE	(1 << 10)
775 #define MX21_CSPICTRL_MASTER	(1 << 11)
776 #define MX21_CSPICTRL_DR_SHIFT	14
777 #define MX21_CSPICTRL_CS_SHIFT	19
778 
779 static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
780 {
781 	unsigned int val = 0;
782 
783 	if (enable & MXC_INT_TE)
784 		val |= MX21_INTREG_TEEN;
785 	if (enable & MXC_INT_RR)
786 		val |= MX21_INTREG_RREN;
787 
788 	writel(val, spi_imx->base + MXC_CSPIINT);
789 }
790 
791 static void mx21_trigger(struct spi_imx_data *spi_imx)
792 {
793 	unsigned int reg;
794 
795 	reg = readl(spi_imx->base + MXC_CSPICTRL);
796 	reg |= MX21_CSPICTRL_XCH;
797 	writel(reg, spi_imx->base + MXC_CSPICTRL);
798 }
799 
800 static int mx21_prepare_message(struct spi_imx_data *spi_imx,
801 				struct spi_message *msg)
802 {
803 	return 0;
804 }
805 
806 static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
807 				 struct spi_device *spi)
808 {
809 	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
810 	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
811 	unsigned int clk;
812 
813 	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, spi_imx->spi_bus_clk, max, &clk)
814 		<< MX21_CSPICTRL_DR_SHIFT;
815 	spi_imx->spi_bus_clk = clk;
816 
817 	reg |= spi_imx->bits_per_word - 1;
818 
819 	if (spi->mode & SPI_CPHA)
820 		reg |= MX21_CSPICTRL_PHA;
821 	if (spi->mode & SPI_CPOL)
822 		reg |= MX21_CSPICTRL_POL;
823 	if (spi->mode & SPI_CS_HIGH)
824 		reg |= MX21_CSPICTRL_SSPOL;
825 	if (!spi->cs_gpiod)
826 		reg |= spi->chip_select << MX21_CSPICTRL_CS_SHIFT;
827 
828 	writel(reg, spi_imx->base + MXC_CSPICTRL);
829 
830 	return 0;
831 }
832 
833 static int mx21_rx_available(struct spi_imx_data *spi_imx)
834 {
835 	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
836 }
837 
838 static void mx21_reset(struct spi_imx_data *spi_imx)
839 {
840 	writel(1, spi_imx->base + MXC_RESET);
841 }
842 
843 #define MX1_INTREG_RR		(1 << 3)
844 #define MX1_INTREG_TEEN		(1 << 8)
845 #define MX1_INTREG_RREN		(1 << 11)
846 
847 #define MX1_CSPICTRL_POL	(1 << 4)
848 #define MX1_CSPICTRL_PHA	(1 << 5)
849 #define MX1_CSPICTRL_XCH	(1 << 8)
850 #define MX1_CSPICTRL_ENABLE	(1 << 9)
851 #define MX1_CSPICTRL_MASTER	(1 << 10)
852 #define MX1_CSPICTRL_DR_SHIFT	13
853 
854 static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
855 {
856 	unsigned int val = 0;
857 
858 	if (enable & MXC_INT_TE)
859 		val |= MX1_INTREG_TEEN;
860 	if (enable & MXC_INT_RR)
861 		val |= MX1_INTREG_RREN;
862 
863 	writel(val, spi_imx->base + MXC_CSPIINT);
864 }
865 
866 static void mx1_trigger(struct spi_imx_data *spi_imx)
867 {
868 	unsigned int reg;
869 
870 	reg = readl(spi_imx->base + MXC_CSPICTRL);
871 	reg |= MX1_CSPICTRL_XCH;
872 	writel(reg, spi_imx->base + MXC_CSPICTRL);
873 }
874 
875 static int mx1_prepare_message(struct spi_imx_data *spi_imx,
876 			       struct spi_message *msg)
877 {
878 	return 0;
879 }
880 
881 static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
882 				struct spi_device *spi)
883 {
884 	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
885 	unsigned int clk;
886 
887 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
888 		MX1_CSPICTRL_DR_SHIFT;
889 	spi_imx->spi_bus_clk = clk;
890 
891 	reg |= spi_imx->bits_per_word - 1;
892 
893 	if (spi->mode & SPI_CPHA)
894 		reg |= MX1_CSPICTRL_PHA;
895 	if (spi->mode & SPI_CPOL)
896 		reg |= MX1_CSPICTRL_POL;
897 
898 	writel(reg, spi_imx->base + MXC_CSPICTRL);
899 
900 	return 0;
901 }
902 
903 static int mx1_rx_available(struct spi_imx_data *spi_imx)
904 {
905 	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
906 }
907 
908 static void mx1_reset(struct spi_imx_data *spi_imx)
909 {
910 	writel(1, spi_imx->base + MXC_RESET);
911 }
912 
913 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
914 	.intctrl = mx1_intctrl,
915 	.prepare_message = mx1_prepare_message,
916 	.prepare_transfer = mx1_prepare_transfer,
917 	.trigger = mx1_trigger,
918 	.rx_available = mx1_rx_available,
919 	.reset = mx1_reset,
920 	.fifo_size = 8,
921 	.has_dmamode = false,
922 	.dynamic_burst = false,
923 	.has_slavemode = false,
924 	.devtype = IMX1_CSPI,
925 };
926 
927 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
928 	.intctrl = mx21_intctrl,
929 	.prepare_message = mx21_prepare_message,
930 	.prepare_transfer = mx21_prepare_transfer,
931 	.trigger = mx21_trigger,
932 	.rx_available = mx21_rx_available,
933 	.reset = mx21_reset,
934 	.fifo_size = 8,
935 	.has_dmamode = false,
936 	.dynamic_burst = false,
937 	.has_slavemode = false,
938 	.devtype = IMX21_CSPI,
939 };
940 
941 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
942 	/* i.mx27 cspi shares the functions with i.mx21 one */
943 	.intctrl = mx21_intctrl,
944 	.prepare_message = mx21_prepare_message,
945 	.prepare_transfer = mx21_prepare_transfer,
946 	.trigger = mx21_trigger,
947 	.rx_available = mx21_rx_available,
948 	.reset = mx21_reset,
949 	.fifo_size = 8,
950 	.has_dmamode = false,
951 	.dynamic_burst = false,
952 	.has_slavemode = false,
953 	.devtype = IMX27_CSPI,
954 };
955 
956 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
957 	.intctrl = mx31_intctrl,
958 	.prepare_message = mx31_prepare_message,
959 	.prepare_transfer = mx31_prepare_transfer,
960 	.trigger = mx31_trigger,
961 	.rx_available = mx31_rx_available,
962 	.reset = mx31_reset,
963 	.fifo_size = 8,
964 	.has_dmamode = false,
965 	.dynamic_burst = false,
966 	.has_slavemode = false,
967 	.devtype = IMX31_CSPI,
968 };
969 
970 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
971 	/* i.mx35 and later cspi shares the functions with i.mx31 one */
972 	.intctrl = mx31_intctrl,
973 	.prepare_message = mx31_prepare_message,
974 	.prepare_transfer = mx31_prepare_transfer,
975 	.trigger = mx31_trigger,
976 	.rx_available = mx31_rx_available,
977 	.reset = mx31_reset,
978 	.fifo_size = 8,
979 	.has_dmamode = true,
980 	.dynamic_burst = false,
981 	.has_slavemode = false,
982 	.devtype = IMX35_CSPI,
983 };
984 
985 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
986 	.intctrl = mx51_ecspi_intctrl,
987 	.prepare_message = mx51_ecspi_prepare_message,
988 	.prepare_transfer = mx51_ecspi_prepare_transfer,
989 	.trigger = mx51_ecspi_trigger,
990 	.rx_available = mx51_ecspi_rx_available,
991 	.reset = mx51_ecspi_reset,
992 	.setup_wml = mx51_setup_wml,
993 	.disable_dma = mx51_disable_dma,
994 	.fifo_size = 64,
995 	.has_dmamode = true,
996 	.dynamic_burst = true,
997 	.has_slavemode = true,
998 	.disable = mx51_ecspi_disable,
999 	.devtype = IMX51_ECSPI,
1000 };
1001 
1002 static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
1003 	.intctrl = mx51_ecspi_intctrl,
1004 	.prepare_message = mx51_ecspi_prepare_message,
1005 	.prepare_transfer = mx51_ecspi_prepare_transfer,
1006 	.trigger = mx51_ecspi_trigger,
1007 	.rx_available = mx51_ecspi_rx_available,
1008 	.disable_dma = mx51_disable_dma,
1009 	.reset = mx51_ecspi_reset,
1010 	.fifo_size = 64,
1011 	.has_dmamode = true,
1012 	.has_slavemode = true,
1013 	.disable = mx51_ecspi_disable,
1014 	.devtype = IMX53_ECSPI,
1015 };
1016 
1017 static const struct of_device_id spi_imx_dt_ids[] = {
1018 	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
1019 	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
1020 	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
1021 	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
1022 	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
1023 	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
1024 	{ .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
1025 	{ /* sentinel */ }
1026 };
1027 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
1028 
1029 static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
1030 {
1031 	u32 ctrl;
1032 
1033 	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
1034 	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
1035 	ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
1036 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
1037 }
1038 
1039 static void spi_imx_push(struct spi_imx_data *spi_imx)
1040 {
1041 	unsigned int burst_len, fifo_words;
1042 
1043 	if (spi_imx->dynamic_burst)
1044 		fifo_words = 4;
1045 	else
1046 		fifo_words = spi_imx_bytes_per_word(spi_imx->bits_per_word);
1047 	/*
1048 	 * Reload the FIFO when the remaining bytes to be transferred in the
1049 	 * current burst is 0. This only applies when bits_per_word is a
1050 	 * multiple of 8.
1051 	 */
1052 	if (!spi_imx->remainder) {
1053 		if (spi_imx->dynamic_burst) {
1054 
1055 			/* We need to deal unaligned data first */
1056 			burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
1057 
1058 			if (!burst_len)
1059 				burst_len = MX51_ECSPI_CTRL_MAX_BURST;
1060 
1061 			spi_imx_set_burst_len(spi_imx, burst_len * 8);
1062 
1063 			spi_imx->remainder = burst_len;
1064 		} else {
1065 			spi_imx->remainder = fifo_words;
1066 		}
1067 	}
1068 
1069 	while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
1070 		if (!spi_imx->count)
1071 			break;
1072 		if (spi_imx->dynamic_burst &&
1073 		    spi_imx->txfifo >= DIV_ROUND_UP(spi_imx->remainder,
1074 						     fifo_words))
1075 			break;
1076 		spi_imx->tx(spi_imx);
1077 		spi_imx->txfifo++;
1078 	}
1079 
1080 	if (!spi_imx->slave_mode)
1081 		spi_imx->devtype_data->trigger(spi_imx);
1082 }
1083 
1084 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
1085 {
1086 	struct spi_imx_data *spi_imx = dev_id;
1087 
1088 	while (spi_imx->txfifo &&
1089 	       spi_imx->devtype_data->rx_available(spi_imx)) {
1090 		spi_imx->rx(spi_imx);
1091 		spi_imx->txfifo--;
1092 	}
1093 
1094 	if (spi_imx->count) {
1095 		spi_imx_push(spi_imx);
1096 		return IRQ_HANDLED;
1097 	}
1098 
1099 	if (spi_imx->txfifo) {
1100 		/* No data left to push, but still waiting for rx data,
1101 		 * enable receive data available interrupt.
1102 		 */
1103 		spi_imx->devtype_data->intctrl(
1104 				spi_imx, MXC_INT_RR);
1105 		return IRQ_HANDLED;
1106 	}
1107 
1108 	spi_imx->devtype_data->intctrl(spi_imx, 0);
1109 	complete(&spi_imx->xfer_done);
1110 
1111 	return IRQ_HANDLED;
1112 }
1113 
1114 static int spi_imx_dma_configure(struct spi_master *master)
1115 {
1116 	int ret;
1117 	enum dma_slave_buswidth buswidth;
1118 	struct dma_slave_config rx = {}, tx = {};
1119 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1120 
1121 	switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
1122 	case 4:
1123 		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
1124 		break;
1125 	case 2:
1126 		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
1127 		break;
1128 	case 1:
1129 		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
1130 		break;
1131 	default:
1132 		return -EINVAL;
1133 	}
1134 
1135 	tx.direction = DMA_MEM_TO_DEV;
1136 	tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
1137 	tx.dst_addr_width = buswidth;
1138 	tx.dst_maxburst = spi_imx->wml;
1139 	ret = dmaengine_slave_config(master->dma_tx, &tx);
1140 	if (ret) {
1141 		dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
1142 		return ret;
1143 	}
1144 
1145 	rx.direction = DMA_DEV_TO_MEM;
1146 	rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
1147 	rx.src_addr_width = buswidth;
1148 	rx.src_maxburst = spi_imx->wml;
1149 	ret = dmaengine_slave_config(master->dma_rx, &rx);
1150 	if (ret) {
1151 		dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
1152 		return ret;
1153 	}
1154 
1155 	return 0;
1156 }
1157 
1158 static int spi_imx_setupxfer(struct spi_device *spi,
1159 				 struct spi_transfer *t)
1160 {
1161 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1162 
1163 	if (!t)
1164 		return 0;
1165 
1166 	if (!t->speed_hz) {
1167 		if (!spi->max_speed_hz) {
1168 			dev_err(&spi->dev, "no speed_hz provided!\n");
1169 			return -EINVAL;
1170 		}
1171 		dev_dbg(&spi->dev, "using spi->max_speed_hz!\n");
1172 		spi_imx->spi_bus_clk = spi->max_speed_hz;
1173 	} else
1174 		spi_imx->spi_bus_clk = t->speed_hz;
1175 
1176 	spi_imx->bits_per_word = t->bits_per_word;
1177 
1178 	/*
1179 	 * Initialize the functions for transfer. To transfer non byte-aligned
1180 	 * words, we have to use multiple word-size bursts, we can't use
1181 	 * dynamic_burst in that case.
1182 	 */
1183 	if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode &&
1184 	    (spi_imx->bits_per_word == 8 ||
1185 	    spi_imx->bits_per_word == 16 ||
1186 	    spi_imx->bits_per_word == 32)) {
1187 
1188 		spi_imx->rx = spi_imx_buf_rx_swap;
1189 		spi_imx->tx = spi_imx_buf_tx_swap;
1190 		spi_imx->dynamic_burst = 1;
1191 
1192 	} else {
1193 		if (spi_imx->bits_per_word <= 8) {
1194 			spi_imx->rx = spi_imx_buf_rx_u8;
1195 			spi_imx->tx = spi_imx_buf_tx_u8;
1196 		} else if (spi_imx->bits_per_word <= 16) {
1197 			spi_imx->rx = spi_imx_buf_rx_u16;
1198 			spi_imx->tx = spi_imx_buf_tx_u16;
1199 		} else {
1200 			spi_imx->rx = spi_imx_buf_rx_u32;
1201 			spi_imx->tx = spi_imx_buf_tx_u32;
1202 		}
1203 		spi_imx->dynamic_burst = 0;
1204 	}
1205 
1206 	if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
1207 		spi_imx->usedma = true;
1208 	else
1209 		spi_imx->usedma = false;
1210 
1211 	if (is_imx53_ecspi(spi_imx) && spi_imx->slave_mode) {
1212 		spi_imx->rx = mx53_ecspi_rx_slave;
1213 		spi_imx->tx = mx53_ecspi_tx_slave;
1214 		spi_imx->slave_burst = t->len;
1215 	}
1216 
1217 	spi_imx->devtype_data->prepare_transfer(spi_imx, spi);
1218 
1219 	return 0;
1220 }
1221 
1222 static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
1223 {
1224 	struct spi_master *master = spi_imx->bitbang.master;
1225 
1226 	if (master->dma_rx) {
1227 		dma_release_channel(master->dma_rx);
1228 		master->dma_rx = NULL;
1229 	}
1230 
1231 	if (master->dma_tx) {
1232 		dma_release_channel(master->dma_tx);
1233 		master->dma_tx = NULL;
1234 	}
1235 }
1236 
1237 static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
1238 			     struct spi_master *master)
1239 {
1240 	int ret;
1241 
1242 	/* use pio mode for i.mx6dl chip TKT238285 */
1243 	if (of_machine_is_compatible("fsl,imx6dl"))
1244 		return 0;
1245 
1246 	spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
1247 
1248 	/* Prepare for TX DMA: */
1249 	master->dma_tx = dma_request_chan(dev, "tx");
1250 	if (IS_ERR(master->dma_tx)) {
1251 		ret = PTR_ERR(master->dma_tx);
1252 		dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
1253 		master->dma_tx = NULL;
1254 		goto err;
1255 	}
1256 
1257 	/* Prepare for RX : */
1258 	master->dma_rx = dma_request_chan(dev, "rx");
1259 	if (IS_ERR(master->dma_rx)) {
1260 		ret = PTR_ERR(master->dma_rx);
1261 		dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
1262 		master->dma_rx = NULL;
1263 		goto err;
1264 	}
1265 
1266 	init_completion(&spi_imx->dma_rx_completion);
1267 	init_completion(&spi_imx->dma_tx_completion);
1268 	master->can_dma = spi_imx_can_dma;
1269 	master->max_dma_len = MAX_SDMA_BD_BYTES;
1270 	spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
1271 					 SPI_MASTER_MUST_TX;
1272 
1273 	return 0;
1274 err:
1275 	spi_imx_sdma_exit(spi_imx);
1276 	return ret;
1277 }
1278 
1279 static void spi_imx_dma_rx_callback(void *cookie)
1280 {
1281 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1282 
1283 	complete(&spi_imx->dma_rx_completion);
1284 }
1285 
1286 static void spi_imx_dma_tx_callback(void *cookie)
1287 {
1288 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1289 
1290 	complete(&spi_imx->dma_tx_completion);
1291 }
1292 
1293 static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1294 {
1295 	unsigned long timeout = 0;
1296 
1297 	/* Time with actual data transfer and CS change delay related to HW */
1298 	timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1299 
1300 	/* Add extra second for scheduler related activities */
1301 	timeout += 1;
1302 
1303 	/* Double calculated timeout */
1304 	return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1305 }
1306 
1307 static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1308 				struct spi_transfer *transfer)
1309 {
1310 	struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1311 	unsigned long transfer_timeout;
1312 	unsigned long timeout;
1313 	struct spi_master *master = spi_imx->bitbang.master;
1314 	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1315 	struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
1316 	unsigned int bytes_per_word, i;
1317 	int ret;
1318 
1319 	/* Get the right burst length from the last sg to ensure no tail data */
1320 	bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
1321 	for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
1322 		if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
1323 			break;
1324 	}
1325 	/* Use 1 as wml in case no available burst length got */
1326 	if (i == 0)
1327 		i = 1;
1328 
1329 	spi_imx->wml =  i;
1330 
1331 	ret = spi_imx_dma_configure(master);
1332 	if (ret)
1333 		goto dma_failure_no_start;
1334 
1335 	if (!spi_imx->devtype_data->setup_wml) {
1336 		dev_err(spi_imx->dev, "No setup_wml()?\n");
1337 		ret = -EINVAL;
1338 		goto dma_failure_no_start;
1339 	}
1340 	spi_imx->devtype_data->setup_wml(spi_imx);
1341 
1342 	/*
1343 	 * The TX DMA setup starts the transfer, so make sure RX is configured
1344 	 * before TX.
1345 	 */
1346 	desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
1347 				rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1348 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1349 	if (!desc_rx) {
1350 		ret = -EINVAL;
1351 		goto dma_failure_no_start;
1352 	}
1353 
1354 	desc_rx->callback = spi_imx_dma_rx_callback;
1355 	desc_rx->callback_param = (void *)spi_imx;
1356 	dmaengine_submit(desc_rx);
1357 	reinit_completion(&spi_imx->dma_rx_completion);
1358 	dma_async_issue_pending(master->dma_rx);
1359 
1360 	desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
1361 				tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1362 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1363 	if (!desc_tx) {
1364 		dmaengine_terminate_all(master->dma_tx);
1365 		dmaengine_terminate_all(master->dma_rx);
1366 		return -EINVAL;
1367 	}
1368 
1369 	desc_tx->callback = spi_imx_dma_tx_callback;
1370 	desc_tx->callback_param = (void *)spi_imx;
1371 	dmaengine_submit(desc_tx);
1372 	reinit_completion(&spi_imx->dma_tx_completion);
1373 	dma_async_issue_pending(master->dma_tx);
1374 
1375 	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1376 
1377 	/* Wait SDMA to finish the data transfer.*/
1378 	timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1379 						transfer_timeout);
1380 	if (!timeout) {
1381 		dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1382 		dmaengine_terminate_all(master->dma_tx);
1383 		dmaengine_terminate_all(master->dma_rx);
1384 		return -ETIMEDOUT;
1385 	}
1386 
1387 	timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1388 					      transfer_timeout);
1389 	if (!timeout) {
1390 		dev_err(&master->dev, "I/O Error in DMA RX\n");
1391 		spi_imx->devtype_data->reset(spi_imx);
1392 		dmaengine_terminate_all(master->dma_rx);
1393 		return -ETIMEDOUT;
1394 	}
1395 
1396 	return transfer->len;
1397 /* fallback to pio */
1398 dma_failure_no_start:
1399 	transfer->error |= SPI_TRANS_FAIL_NO_START;
1400 	return ret;
1401 }
1402 
1403 static int spi_imx_pio_transfer(struct spi_device *spi,
1404 				struct spi_transfer *transfer)
1405 {
1406 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1407 	unsigned long transfer_timeout;
1408 	unsigned long timeout;
1409 
1410 	spi_imx->tx_buf = transfer->tx_buf;
1411 	spi_imx->rx_buf = transfer->rx_buf;
1412 	spi_imx->count = transfer->len;
1413 	spi_imx->txfifo = 0;
1414 	spi_imx->remainder = 0;
1415 
1416 	reinit_completion(&spi_imx->xfer_done);
1417 
1418 	spi_imx_push(spi_imx);
1419 
1420 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1421 
1422 	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1423 
1424 	timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
1425 					      transfer_timeout);
1426 	if (!timeout) {
1427 		dev_err(&spi->dev, "I/O Error in PIO\n");
1428 		spi_imx->devtype_data->reset(spi_imx);
1429 		return -ETIMEDOUT;
1430 	}
1431 
1432 	return transfer->len;
1433 }
1434 
1435 static int spi_imx_pio_transfer_slave(struct spi_device *spi,
1436 				      struct spi_transfer *transfer)
1437 {
1438 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1439 	int ret = transfer->len;
1440 
1441 	if (is_imx53_ecspi(spi_imx) &&
1442 	    transfer->len > MX53_MAX_TRANSFER_BYTES) {
1443 		dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
1444 			MX53_MAX_TRANSFER_BYTES);
1445 		return -EMSGSIZE;
1446 	}
1447 
1448 	spi_imx->tx_buf = transfer->tx_buf;
1449 	spi_imx->rx_buf = transfer->rx_buf;
1450 	spi_imx->count = transfer->len;
1451 	spi_imx->txfifo = 0;
1452 	spi_imx->remainder = 0;
1453 
1454 	reinit_completion(&spi_imx->xfer_done);
1455 	spi_imx->slave_aborted = false;
1456 
1457 	spi_imx_push(spi_imx);
1458 
1459 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
1460 
1461 	if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
1462 	    spi_imx->slave_aborted) {
1463 		dev_dbg(&spi->dev, "interrupted\n");
1464 		ret = -EINTR;
1465 	}
1466 
1467 	/* ecspi has a HW issue when works in Slave mode,
1468 	 * after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
1469 	 * ECSPI_TXDATA keeps shift out the last word data,
1470 	 * so we have to disable ECSPI when in slave mode after the
1471 	 * transfer completes
1472 	 */
1473 	if (spi_imx->devtype_data->disable)
1474 		spi_imx->devtype_data->disable(spi_imx);
1475 
1476 	return ret;
1477 }
1478 
1479 static int spi_imx_transfer(struct spi_device *spi,
1480 				struct spi_transfer *transfer)
1481 {
1482 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1483 
1484 	transfer->effective_speed_hz = spi_imx->spi_bus_clk;
1485 
1486 	/* flush rxfifo before transfer */
1487 	while (spi_imx->devtype_data->rx_available(spi_imx))
1488 		readl(spi_imx->base + MXC_CSPIRXDATA);
1489 
1490 	if (spi_imx->slave_mode)
1491 		return spi_imx_pio_transfer_slave(spi, transfer);
1492 
1493 	if (spi_imx->usedma)
1494 		return spi_imx_dma_transfer(spi_imx, transfer);
1495 
1496 	return spi_imx_pio_transfer(spi, transfer);
1497 }
1498 
1499 static int spi_imx_setup(struct spi_device *spi)
1500 {
1501 	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1502 		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1503 
1504 	return 0;
1505 }
1506 
1507 static void spi_imx_cleanup(struct spi_device *spi)
1508 {
1509 }
1510 
1511 static int
1512 spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1513 {
1514 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1515 	int ret;
1516 
1517 	ret = pm_runtime_get_sync(spi_imx->dev);
1518 	if (ret < 0) {
1519 		pm_runtime_put_noidle(spi_imx->dev);
1520 		dev_err(spi_imx->dev, "failed to enable clock\n");
1521 		return ret;
1522 	}
1523 
1524 	ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
1525 	if (ret) {
1526 		pm_runtime_mark_last_busy(spi_imx->dev);
1527 		pm_runtime_put_autosuspend(spi_imx->dev);
1528 	}
1529 
1530 	return ret;
1531 }
1532 
1533 static int
1534 spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1535 {
1536 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1537 
1538 	pm_runtime_mark_last_busy(spi_imx->dev);
1539 	pm_runtime_put_autosuspend(spi_imx->dev);
1540 	return 0;
1541 }
1542 
1543 static int spi_imx_slave_abort(struct spi_master *master)
1544 {
1545 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1546 
1547 	spi_imx->slave_aborted = true;
1548 	complete(&spi_imx->xfer_done);
1549 
1550 	return 0;
1551 }
1552 
1553 static int spi_imx_probe(struct platform_device *pdev)
1554 {
1555 	struct device_node *np = pdev->dev.of_node;
1556 	struct spi_master *master;
1557 	struct spi_imx_data *spi_imx;
1558 	struct resource *res;
1559 	int ret, irq, spi_drctl;
1560 	const struct spi_imx_devtype_data *devtype_data =
1561 			of_device_get_match_data(&pdev->dev);
1562 	bool slave_mode;
1563 	u32 val;
1564 
1565 	slave_mode = devtype_data->has_slavemode &&
1566 			of_property_read_bool(np, "spi-slave");
1567 	if (slave_mode)
1568 		master = spi_alloc_slave(&pdev->dev,
1569 					 sizeof(struct spi_imx_data));
1570 	else
1571 		master = spi_alloc_master(&pdev->dev,
1572 					  sizeof(struct spi_imx_data));
1573 	if (!master)
1574 		return -ENOMEM;
1575 
1576 	ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
1577 	if ((ret < 0) || (spi_drctl >= 0x3)) {
1578 		/* '11' is reserved */
1579 		spi_drctl = 0;
1580 	}
1581 
1582 	platform_set_drvdata(pdev, master);
1583 
1584 	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1585 	master->bus_num = np ? -1 : pdev->id;
1586 	master->use_gpio_descriptors = true;
1587 
1588 	spi_imx = spi_master_get_devdata(master);
1589 	spi_imx->bitbang.master = master;
1590 	spi_imx->dev = &pdev->dev;
1591 	spi_imx->slave_mode = slave_mode;
1592 
1593 	spi_imx->devtype_data = devtype_data;
1594 
1595 	/*
1596 	 * Get number of chip selects from device properties. This can be
1597 	 * coming from device tree or boardfiles, if it is not defined,
1598 	 * a default value of 3 chip selects will be used, as all the legacy
1599 	 * board files have <= 3 chip selects.
1600 	 */
1601 	if (!device_property_read_u32(&pdev->dev, "num-cs", &val))
1602 		master->num_chipselect = val;
1603 	else
1604 		master->num_chipselect = 3;
1605 
1606 	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1607 	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1608 	spi_imx->bitbang.master->setup = spi_imx_setup;
1609 	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1610 	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1611 	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1612 	spi_imx->bitbang.master->slave_abort = spi_imx_slave_abort;
1613 	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
1614 					     | SPI_NO_CS;
1615 	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
1616 	    is_imx53_ecspi(spi_imx))
1617 		spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY;
1618 
1619 	spi_imx->spi_drctl = spi_drctl;
1620 
1621 	init_completion(&spi_imx->xfer_done);
1622 
1623 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1624 	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1625 	if (IS_ERR(spi_imx->base)) {
1626 		ret = PTR_ERR(spi_imx->base);
1627 		goto out_master_put;
1628 	}
1629 	spi_imx->base_phys = res->start;
1630 
1631 	irq = platform_get_irq(pdev, 0);
1632 	if (irq < 0) {
1633 		ret = irq;
1634 		goto out_master_put;
1635 	}
1636 
1637 	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1638 			       dev_name(&pdev->dev), spi_imx);
1639 	if (ret) {
1640 		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1641 		goto out_master_put;
1642 	}
1643 
1644 	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1645 	if (IS_ERR(spi_imx->clk_ipg)) {
1646 		ret = PTR_ERR(spi_imx->clk_ipg);
1647 		goto out_master_put;
1648 	}
1649 
1650 	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1651 	if (IS_ERR(spi_imx->clk_per)) {
1652 		ret = PTR_ERR(spi_imx->clk_per);
1653 		goto out_master_put;
1654 	}
1655 
1656 	ret = clk_prepare_enable(spi_imx->clk_per);
1657 	if (ret)
1658 		goto out_master_put;
1659 
1660 	ret = clk_prepare_enable(spi_imx->clk_ipg);
1661 	if (ret)
1662 		goto out_put_per;
1663 
1664 	pm_runtime_set_autosuspend_delay(spi_imx->dev, MXC_RPM_TIMEOUT);
1665 	pm_runtime_use_autosuspend(spi_imx->dev);
1666 	pm_runtime_get_noresume(spi_imx->dev);
1667 	pm_runtime_set_active(spi_imx->dev);
1668 	pm_runtime_enable(spi_imx->dev);
1669 
1670 	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1671 	/*
1672 	 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1673 	 * if validated on other chips.
1674 	 */
1675 	if (spi_imx->devtype_data->has_dmamode) {
1676 		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
1677 		if (ret == -EPROBE_DEFER)
1678 			goto out_runtime_pm_put;
1679 
1680 		if (ret < 0)
1681 			dev_dbg(&pdev->dev, "dma setup error %d, use pio\n",
1682 				ret);
1683 	}
1684 
1685 	spi_imx->devtype_data->reset(spi_imx);
1686 
1687 	spi_imx->devtype_data->intctrl(spi_imx, 0);
1688 
1689 	master->dev.of_node = pdev->dev.of_node;
1690 	ret = spi_bitbang_start(&spi_imx->bitbang);
1691 	if (ret) {
1692 		dev_err_probe(&pdev->dev, ret, "bitbang start failed\n");
1693 		goto out_bitbang_start;
1694 	}
1695 
1696 	pm_runtime_mark_last_busy(spi_imx->dev);
1697 	pm_runtime_put_autosuspend(spi_imx->dev);
1698 
1699 	return ret;
1700 
1701 out_bitbang_start:
1702 	if (spi_imx->devtype_data->has_dmamode)
1703 		spi_imx_sdma_exit(spi_imx);
1704 out_runtime_pm_put:
1705 	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1706 	pm_runtime_set_suspended(&pdev->dev);
1707 	pm_runtime_disable(spi_imx->dev);
1708 
1709 	clk_disable_unprepare(spi_imx->clk_ipg);
1710 out_put_per:
1711 	clk_disable_unprepare(spi_imx->clk_per);
1712 out_master_put:
1713 	spi_master_put(master);
1714 
1715 	return ret;
1716 }
1717 
1718 static int spi_imx_remove(struct platform_device *pdev)
1719 {
1720 	struct spi_master *master = platform_get_drvdata(pdev);
1721 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1722 	int ret;
1723 
1724 	spi_bitbang_stop(&spi_imx->bitbang);
1725 
1726 	ret = pm_runtime_get_sync(spi_imx->dev);
1727 	if (ret < 0) {
1728 		pm_runtime_put_noidle(spi_imx->dev);
1729 		dev_err(spi_imx->dev, "failed to enable clock\n");
1730 		return ret;
1731 	}
1732 
1733 	writel(0, spi_imx->base + MXC_CSPICTRL);
1734 
1735 	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1736 	pm_runtime_put_sync(spi_imx->dev);
1737 	pm_runtime_disable(spi_imx->dev);
1738 
1739 	spi_imx_sdma_exit(spi_imx);
1740 	spi_master_put(master);
1741 
1742 	return 0;
1743 }
1744 
1745 static int __maybe_unused spi_imx_runtime_resume(struct device *dev)
1746 {
1747 	struct spi_master *master = dev_get_drvdata(dev);
1748 	struct spi_imx_data *spi_imx;
1749 	int ret;
1750 
1751 	spi_imx = spi_master_get_devdata(master);
1752 
1753 	ret = clk_prepare_enable(spi_imx->clk_per);
1754 	if (ret)
1755 		return ret;
1756 
1757 	ret = clk_prepare_enable(spi_imx->clk_ipg);
1758 	if (ret) {
1759 		clk_disable_unprepare(spi_imx->clk_per);
1760 		return ret;
1761 	}
1762 
1763 	return 0;
1764 }
1765 
1766 static int __maybe_unused spi_imx_runtime_suspend(struct device *dev)
1767 {
1768 	struct spi_master *master = dev_get_drvdata(dev);
1769 	struct spi_imx_data *spi_imx;
1770 
1771 	spi_imx = spi_master_get_devdata(master);
1772 
1773 	clk_disable_unprepare(spi_imx->clk_per);
1774 	clk_disable_unprepare(spi_imx->clk_ipg);
1775 
1776 	return 0;
1777 }
1778 
1779 static int __maybe_unused spi_imx_suspend(struct device *dev)
1780 {
1781 	pinctrl_pm_select_sleep_state(dev);
1782 	return 0;
1783 }
1784 
1785 static int __maybe_unused spi_imx_resume(struct device *dev)
1786 {
1787 	pinctrl_pm_select_default_state(dev);
1788 	return 0;
1789 }
1790 
1791 static const struct dev_pm_ops imx_spi_pm = {
1792 	SET_RUNTIME_PM_OPS(spi_imx_runtime_suspend,
1793 				spi_imx_runtime_resume, NULL)
1794 	SET_SYSTEM_SLEEP_PM_OPS(spi_imx_suspend, spi_imx_resume)
1795 };
1796 
1797 static struct platform_driver spi_imx_driver = {
1798 	.driver = {
1799 		   .name = DRIVER_NAME,
1800 		   .of_match_table = spi_imx_dt_ids,
1801 		   .pm = &imx_spi_pm,
1802 	},
1803 	.probe = spi_imx_probe,
1804 	.remove = spi_imx_remove,
1805 };
1806 module_platform_driver(spi_imx_driver);
1807 
1808 MODULE_DESCRIPTION("i.MX SPI Controller driver");
1809 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1810 MODULE_LICENSE("GPL");
1811 MODULE_ALIAS("platform:" DRIVER_NAME);
1812