xref: /linux/drivers/spi/spi-imx.c (revision 0c8a32eed1625a65798286fb73fea8710a908545)
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 				struct spi_transfer *);
71 	void (*trigger)(struct spi_imx_data *);
72 	int (*rx_available)(struct spi_imx_data *);
73 	void (*reset)(struct spi_imx_data *);
74 	void (*setup_wml)(struct spi_imx_data *);
75 	void (*disable)(struct spi_imx_data *);
76 	void (*disable_dma)(struct spi_imx_data *);
77 	bool has_dmamode;
78 	bool has_slavemode;
79 	unsigned int fifo_size;
80 	bool dynamic_burst;
81 	enum spi_imx_devtype devtype;
82 };
83 
84 struct spi_imx_data {
85 	struct spi_bitbang bitbang;
86 	struct device *dev;
87 
88 	struct completion xfer_done;
89 	void __iomem *base;
90 	unsigned long base_phys;
91 
92 	struct clk *clk_per;
93 	struct clk *clk_ipg;
94 	unsigned long spi_clk;
95 	unsigned int spi_bus_clk;
96 
97 	unsigned int bits_per_word;
98 	unsigned int spi_drctl;
99 
100 	unsigned int count, remainder;
101 	void (*tx)(struct spi_imx_data *);
102 	void (*rx)(struct spi_imx_data *);
103 	void *rx_buf;
104 	const void *tx_buf;
105 	unsigned int txfifo; /* number of words pushed in tx FIFO */
106 	unsigned int dynamic_burst;
107 
108 	/* Slave mode */
109 	bool slave_mode;
110 	bool slave_aborted;
111 	unsigned int slave_burst;
112 
113 	/* DMA */
114 	bool usedma;
115 	u32 wml;
116 	struct completion dma_rx_completion;
117 	struct completion dma_tx_completion;
118 
119 	const struct spi_imx_devtype_data *devtype_data;
120 };
121 
122 static inline int is_imx27_cspi(struct spi_imx_data *d)
123 {
124 	return d->devtype_data->devtype == IMX27_CSPI;
125 }
126 
127 static inline int is_imx35_cspi(struct spi_imx_data *d)
128 {
129 	return d->devtype_data->devtype == IMX35_CSPI;
130 }
131 
132 static inline int is_imx51_ecspi(struct spi_imx_data *d)
133 {
134 	return d->devtype_data->devtype == IMX51_ECSPI;
135 }
136 
137 static inline int is_imx53_ecspi(struct spi_imx_data *d)
138 {
139 	return d->devtype_data->devtype == IMX53_ECSPI;
140 }
141 
142 #define MXC_SPI_BUF_RX(type)						\
143 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
144 {									\
145 	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
146 									\
147 	if (spi_imx->rx_buf) {						\
148 		*(type *)spi_imx->rx_buf = val;				\
149 		spi_imx->rx_buf += sizeof(type);			\
150 	}								\
151 									\
152 	spi_imx->remainder -= sizeof(type);				\
153 }
154 
155 #define MXC_SPI_BUF_TX(type)						\
156 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
157 {									\
158 	type val = 0;							\
159 									\
160 	if (spi_imx->tx_buf) {						\
161 		val = *(type *)spi_imx->tx_buf;				\
162 		spi_imx->tx_buf += sizeof(type);			\
163 	}								\
164 									\
165 	spi_imx->count -= sizeof(type);					\
166 									\
167 	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
168 }
169 
170 MXC_SPI_BUF_RX(u8)
171 MXC_SPI_BUF_TX(u8)
172 MXC_SPI_BUF_RX(u16)
173 MXC_SPI_BUF_TX(u16)
174 MXC_SPI_BUF_RX(u32)
175 MXC_SPI_BUF_TX(u32)
176 
177 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
178  * (which is currently not the case in this driver)
179  */
180 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
181 	256, 384, 512, 768, 1024};
182 
183 /* MX21, MX27 */
184 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
185 		unsigned int fspi, unsigned int max, unsigned int *fres)
186 {
187 	int i;
188 
189 	for (i = 2; i < max; i++)
190 		if (fspi * mxc_clkdivs[i] >= fin)
191 			break;
192 
193 	*fres = fin / mxc_clkdivs[i];
194 	return i;
195 }
196 
197 /* MX1, MX31, MX35, MX51 CSPI */
198 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
199 		unsigned int fspi, unsigned int *fres)
200 {
201 	int i, div = 4;
202 
203 	for (i = 0; i < 7; i++) {
204 		if (fspi * div >= fin)
205 			goto out;
206 		div <<= 1;
207 	}
208 
209 out:
210 	*fres = fin / div;
211 	return i;
212 }
213 
214 static int spi_imx_bytes_per_word(const int bits_per_word)
215 {
216 	if (bits_per_word <= 8)
217 		return 1;
218 	else if (bits_per_word <= 16)
219 		return 2;
220 	else
221 		return 4;
222 }
223 
224 static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
225 			 struct spi_transfer *transfer)
226 {
227 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
228 
229 	if (!use_dma || master->fallback)
230 		return false;
231 
232 	if (!master->dma_rx)
233 		return false;
234 
235 	if (spi_imx->slave_mode)
236 		return false;
237 
238 	if (transfer->len < spi_imx->devtype_data->fifo_size)
239 		return false;
240 
241 	spi_imx->dynamic_burst = 0;
242 
243 	return true;
244 }
245 
246 #define MX51_ECSPI_CTRL		0x08
247 #define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
248 #define MX51_ECSPI_CTRL_XCH		(1 <<  2)
249 #define MX51_ECSPI_CTRL_SMC		(1 << 3)
250 #define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
251 #define MX51_ECSPI_CTRL_DRCTL(drctl)	((drctl) << 16)
252 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
253 #define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
254 #define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
255 #define MX51_ECSPI_CTRL_BL_OFFSET	20
256 #define MX51_ECSPI_CTRL_BL_MASK		(0xfff << 20)
257 
258 #define MX51_ECSPI_CONFIG	0x0c
259 #define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
260 #define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
261 #define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
262 #define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
263 #define MX51_ECSPI_CONFIG_SCLKCTL(cs)	(1 << ((cs) + 20))
264 
265 #define MX51_ECSPI_INT		0x10
266 #define MX51_ECSPI_INT_TEEN		(1 <<  0)
267 #define MX51_ECSPI_INT_RREN		(1 <<  3)
268 #define MX51_ECSPI_INT_RDREN		(1 <<  4)
269 
270 #define MX51_ECSPI_DMA		0x14
271 #define MX51_ECSPI_DMA_TX_WML(wml)	((wml) & 0x3f)
272 #define MX51_ECSPI_DMA_RX_WML(wml)	(((wml) & 0x3f) << 16)
273 #define MX51_ECSPI_DMA_RXT_WML(wml)	(((wml) & 0x3f) << 24)
274 
275 #define MX51_ECSPI_DMA_TEDEN		(1 << 7)
276 #define MX51_ECSPI_DMA_RXDEN		(1 << 23)
277 #define MX51_ECSPI_DMA_RXTDEN		(1 << 31)
278 
279 #define MX51_ECSPI_STAT		0x18
280 #define MX51_ECSPI_STAT_RR		(1 <<  3)
281 
282 #define MX51_ECSPI_TESTREG	0x20
283 #define MX51_ECSPI_TESTREG_LBC	BIT(31)
284 
285 static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
286 {
287 	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
288 #ifdef __LITTLE_ENDIAN
289 	unsigned int bytes_per_word;
290 #endif
291 
292 	if (spi_imx->rx_buf) {
293 #ifdef __LITTLE_ENDIAN
294 		bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
295 		if (bytes_per_word == 1)
296 			val = cpu_to_be32(val);
297 		else if (bytes_per_word == 2)
298 			val = (val << 16) | (val >> 16);
299 #endif
300 		*(u32 *)spi_imx->rx_buf = val;
301 		spi_imx->rx_buf += sizeof(u32);
302 	}
303 
304 	spi_imx->remainder -= sizeof(u32);
305 }
306 
307 static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
308 {
309 	int unaligned;
310 	u32 val;
311 
312 	unaligned = spi_imx->remainder % 4;
313 
314 	if (!unaligned) {
315 		spi_imx_buf_rx_swap_u32(spi_imx);
316 		return;
317 	}
318 
319 	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
320 		spi_imx_buf_rx_u16(spi_imx);
321 		return;
322 	}
323 
324 	val = readl(spi_imx->base + MXC_CSPIRXDATA);
325 
326 	while (unaligned--) {
327 		if (spi_imx->rx_buf) {
328 			*(u8 *)spi_imx->rx_buf = (val >> (8 * unaligned)) & 0xff;
329 			spi_imx->rx_buf++;
330 		}
331 		spi_imx->remainder--;
332 	}
333 }
334 
335 static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
336 {
337 	u32 val = 0;
338 #ifdef __LITTLE_ENDIAN
339 	unsigned int bytes_per_word;
340 #endif
341 
342 	if (spi_imx->tx_buf) {
343 		val = *(u32 *)spi_imx->tx_buf;
344 		spi_imx->tx_buf += sizeof(u32);
345 	}
346 
347 	spi_imx->count -= sizeof(u32);
348 #ifdef __LITTLE_ENDIAN
349 	bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
350 
351 	if (bytes_per_word == 1)
352 		val = cpu_to_be32(val);
353 	else if (bytes_per_word == 2)
354 		val = (val << 16) | (val >> 16);
355 #endif
356 	writel(val, spi_imx->base + MXC_CSPITXDATA);
357 }
358 
359 static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
360 {
361 	int unaligned;
362 	u32 val = 0;
363 
364 	unaligned = spi_imx->count % 4;
365 
366 	if (!unaligned) {
367 		spi_imx_buf_tx_swap_u32(spi_imx);
368 		return;
369 	}
370 
371 	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
372 		spi_imx_buf_tx_u16(spi_imx);
373 		return;
374 	}
375 
376 	while (unaligned--) {
377 		if (spi_imx->tx_buf) {
378 			val |= *(u8 *)spi_imx->tx_buf << (8 * unaligned);
379 			spi_imx->tx_buf++;
380 		}
381 		spi_imx->count--;
382 	}
383 
384 	writel(val, spi_imx->base + MXC_CSPITXDATA);
385 }
386 
387 static void mx53_ecspi_rx_slave(struct spi_imx_data *spi_imx)
388 {
389 	u32 val = be32_to_cpu(readl(spi_imx->base + MXC_CSPIRXDATA));
390 
391 	if (spi_imx->rx_buf) {
392 		int n_bytes = spi_imx->slave_burst % sizeof(val);
393 
394 		if (!n_bytes)
395 			n_bytes = sizeof(val);
396 
397 		memcpy(spi_imx->rx_buf,
398 		       ((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
399 
400 		spi_imx->rx_buf += n_bytes;
401 		spi_imx->slave_burst -= n_bytes;
402 	}
403 
404 	spi_imx->remainder -= sizeof(u32);
405 }
406 
407 static void mx53_ecspi_tx_slave(struct spi_imx_data *spi_imx)
408 {
409 	u32 val = 0;
410 	int n_bytes = spi_imx->count % sizeof(val);
411 
412 	if (!n_bytes)
413 		n_bytes = sizeof(val);
414 
415 	if (spi_imx->tx_buf) {
416 		memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
417 		       spi_imx->tx_buf, n_bytes);
418 		val = cpu_to_be32(val);
419 		spi_imx->tx_buf += n_bytes;
420 	}
421 
422 	spi_imx->count -= n_bytes;
423 
424 	writel(val, spi_imx->base + MXC_CSPITXDATA);
425 }
426 
427 /* MX51 eCSPI */
428 static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
429 				      unsigned int fspi, unsigned int *fres)
430 {
431 	/*
432 	 * there are two 4-bit dividers, the pre-divider divides by
433 	 * $pre, the post-divider by 2^$post
434 	 */
435 	unsigned int pre, post;
436 	unsigned int fin = spi_imx->spi_clk;
437 
438 	if (unlikely(fspi > fin))
439 		return 0;
440 
441 	post = fls(fin) - fls(fspi);
442 	if (fin > fspi << post)
443 		post++;
444 
445 	/* now we have: (fin <= fspi << post) with post being minimal */
446 
447 	post = max(4U, post) - 4;
448 	if (unlikely(post > 0xf)) {
449 		dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
450 				fspi, fin);
451 		return 0xff;
452 	}
453 
454 	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
455 
456 	dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
457 			__func__, fin, fspi, post, pre);
458 
459 	/* Resulting frequency for the SCLK line. */
460 	*fres = (fin / (pre + 1)) >> post;
461 
462 	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
463 		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
464 }
465 
466 static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
467 {
468 	unsigned val = 0;
469 
470 	if (enable & MXC_INT_TE)
471 		val |= MX51_ECSPI_INT_TEEN;
472 
473 	if (enable & MXC_INT_RR)
474 		val |= MX51_ECSPI_INT_RREN;
475 
476 	if (enable & MXC_INT_RDR)
477 		val |= MX51_ECSPI_INT_RDREN;
478 
479 	writel(val, spi_imx->base + MX51_ECSPI_INT);
480 }
481 
482 static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
483 {
484 	u32 reg;
485 
486 	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
487 	reg |= MX51_ECSPI_CTRL_XCH;
488 	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
489 }
490 
491 static void mx51_disable_dma(struct spi_imx_data *spi_imx)
492 {
493 	writel(0, spi_imx->base + MX51_ECSPI_DMA);
494 }
495 
496 static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
497 {
498 	u32 ctrl;
499 
500 	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
501 	ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
502 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
503 }
504 
505 static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
506 				      struct spi_message *msg)
507 {
508 	struct spi_device *spi = msg->spi;
509 	u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
510 	u32 testreg;
511 	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
512 
513 	/* set Master or Slave mode */
514 	if (spi_imx->slave_mode)
515 		ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
516 	else
517 		ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
518 
519 	/*
520 	 * Enable SPI_RDY handling (falling edge/level triggered).
521 	 */
522 	if (spi->mode & SPI_READY)
523 		ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
524 
525 	/* set chip select to use */
526 	ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
527 
528 	/*
529 	 * The ctrl register must be written first, with the EN bit set other
530 	 * registers must not be written to.
531 	 */
532 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
533 
534 	testreg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
535 	if (spi->mode & SPI_LOOP)
536 		testreg |= MX51_ECSPI_TESTREG_LBC;
537 	else
538 		testreg &= ~MX51_ECSPI_TESTREG_LBC;
539 	writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
540 
541 	/*
542 	 * eCSPI burst completion by Chip Select signal in Slave mode
543 	 * is not functional for imx53 Soc, config SPI burst completed when
544 	 * BURST_LENGTH + 1 bits are received
545 	 */
546 	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
547 		cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
548 	else
549 		cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
550 
551 	if (spi->mode & SPI_CPHA)
552 		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
553 	else
554 		cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
555 
556 	if (spi->mode & SPI_CPOL) {
557 		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
558 		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
559 	} else {
560 		cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
561 		cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
562 	}
563 
564 	if (spi->mode & SPI_CS_HIGH)
565 		cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
566 	else
567 		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
568 
569 	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
570 
571 	return 0;
572 }
573 
574 static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
575 				       struct spi_device *spi,
576 				       struct spi_transfer *t)
577 {
578 	u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
579 	u32 clk = t->speed_hz, delay;
580 
581 	/* Clear BL field and set the right value */
582 	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
583 	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
584 		ctrl |= (spi_imx->slave_burst * 8 - 1)
585 			<< MX51_ECSPI_CTRL_BL_OFFSET;
586 	else
587 		ctrl |= (spi_imx->bits_per_word - 1)
588 			<< MX51_ECSPI_CTRL_BL_OFFSET;
589 
590 	/* set clock speed */
591 	ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
592 		  0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
593 	ctrl |= mx51_ecspi_clkdiv(spi_imx, t->speed_hz, &clk);
594 	spi_imx->spi_bus_clk = clk;
595 
596 	if (spi_imx->usedma)
597 		ctrl |= MX51_ECSPI_CTRL_SMC;
598 
599 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
600 
601 	/*
602 	 * Wait until the changes in the configuration register CONFIGREG
603 	 * propagate into the hardware. It takes exactly one tick of the
604 	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
605 	 * effect of the delay it takes for the hardware to apply changes
606 	 * is noticable if the SCLK clock run very slow. In such a case, if
607 	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
608 	 * be asserted before the SCLK polarity changes, which would disrupt
609 	 * the SPI communication as the device on the other end would consider
610 	 * the change of SCLK polarity as a clock tick already.
611 	 */
612 	delay = (2 * 1000000) / clk;
613 	if (likely(delay < 10))	/* SCLK is faster than 100 kHz */
614 		udelay(delay);
615 	else			/* SCLK is _very_ slow */
616 		usleep_range(delay, delay + 10);
617 
618 	return 0;
619 }
620 
621 static void mx51_setup_wml(struct spi_imx_data *spi_imx)
622 {
623 	/*
624 	 * Configure the DMA register: setup the watermark
625 	 * and enable DMA request.
626 	 */
627 	writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) |
628 		MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
629 		MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
630 		MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
631 		MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
632 }
633 
634 static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
635 {
636 	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
637 }
638 
639 static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
640 {
641 	/* drain receive buffer */
642 	while (mx51_ecspi_rx_available(spi_imx))
643 		readl(spi_imx->base + MXC_CSPIRXDATA);
644 }
645 
646 #define MX31_INTREG_TEEN	(1 << 0)
647 #define MX31_INTREG_RREN	(1 << 3)
648 
649 #define MX31_CSPICTRL_ENABLE	(1 << 0)
650 #define MX31_CSPICTRL_MASTER	(1 << 1)
651 #define MX31_CSPICTRL_XCH	(1 << 2)
652 #define MX31_CSPICTRL_SMC	(1 << 3)
653 #define MX31_CSPICTRL_POL	(1 << 4)
654 #define MX31_CSPICTRL_PHA	(1 << 5)
655 #define MX31_CSPICTRL_SSCTL	(1 << 6)
656 #define MX31_CSPICTRL_SSPOL	(1 << 7)
657 #define MX31_CSPICTRL_BC_SHIFT	8
658 #define MX35_CSPICTRL_BL_SHIFT	20
659 #define MX31_CSPICTRL_CS_SHIFT	24
660 #define MX35_CSPICTRL_CS_SHIFT	12
661 #define MX31_CSPICTRL_DR_SHIFT	16
662 
663 #define MX31_CSPI_DMAREG	0x10
664 #define MX31_DMAREG_RH_DEN	(1<<4)
665 #define MX31_DMAREG_TH_DEN	(1<<1)
666 
667 #define MX31_CSPISTATUS		0x14
668 #define MX31_STATUS_RR		(1 << 3)
669 
670 #define MX31_CSPI_TESTREG	0x1C
671 #define MX31_TEST_LBC		(1 << 14)
672 
673 /* These functions also work for the i.MX35, but be aware that
674  * the i.MX35 has a slightly different register layout for bits
675  * we do not use here.
676  */
677 static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
678 {
679 	unsigned int val = 0;
680 
681 	if (enable & MXC_INT_TE)
682 		val |= MX31_INTREG_TEEN;
683 	if (enable & MXC_INT_RR)
684 		val |= MX31_INTREG_RREN;
685 
686 	writel(val, spi_imx->base + MXC_CSPIINT);
687 }
688 
689 static void mx31_trigger(struct spi_imx_data *spi_imx)
690 {
691 	unsigned int reg;
692 
693 	reg = readl(spi_imx->base + MXC_CSPICTRL);
694 	reg |= MX31_CSPICTRL_XCH;
695 	writel(reg, spi_imx->base + MXC_CSPICTRL);
696 }
697 
698 static int mx31_prepare_message(struct spi_imx_data *spi_imx,
699 				struct spi_message *msg)
700 {
701 	return 0;
702 }
703 
704 static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
705 				 struct spi_device *spi,
706 				 struct spi_transfer *t)
707 {
708 	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
709 	unsigned int clk;
710 
711 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, t->speed_hz, &clk) <<
712 		MX31_CSPICTRL_DR_SHIFT;
713 	spi_imx->spi_bus_clk = clk;
714 
715 	if (is_imx35_cspi(spi_imx)) {
716 		reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
717 		reg |= MX31_CSPICTRL_SSCTL;
718 	} else {
719 		reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
720 	}
721 
722 	if (spi->mode & SPI_CPHA)
723 		reg |= MX31_CSPICTRL_PHA;
724 	if (spi->mode & SPI_CPOL)
725 		reg |= MX31_CSPICTRL_POL;
726 	if (spi->mode & SPI_CS_HIGH)
727 		reg |= MX31_CSPICTRL_SSPOL;
728 	if (!spi->cs_gpiod)
729 		reg |= (spi->chip_select) <<
730 			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
731 						  MX31_CSPICTRL_CS_SHIFT);
732 
733 	if (spi_imx->usedma)
734 		reg |= MX31_CSPICTRL_SMC;
735 
736 	writel(reg, spi_imx->base + MXC_CSPICTRL);
737 
738 	reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
739 	if (spi->mode & SPI_LOOP)
740 		reg |= MX31_TEST_LBC;
741 	else
742 		reg &= ~MX31_TEST_LBC;
743 	writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
744 
745 	if (spi_imx->usedma) {
746 		/*
747 		 * configure DMA requests when RXFIFO is half full and
748 		 * when TXFIFO is half empty
749 		 */
750 		writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
751 			spi_imx->base + MX31_CSPI_DMAREG);
752 	}
753 
754 	return 0;
755 }
756 
757 static int mx31_rx_available(struct spi_imx_data *spi_imx)
758 {
759 	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
760 }
761 
762 static void mx31_reset(struct spi_imx_data *spi_imx)
763 {
764 	/* drain receive buffer */
765 	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
766 		readl(spi_imx->base + MXC_CSPIRXDATA);
767 }
768 
769 #define MX21_INTREG_RR		(1 << 4)
770 #define MX21_INTREG_TEEN	(1 << 9)
771 #define MX21_INTREG_RREN	(1 << 13)
772 
773 #define MX21_CSPICTRL_POL	(1 << 5)
774 #define MX21_CSPICTRL_PHA	(1 << 6)
775 #define MX21_CSPICTRL_SSPOL	(1 << 8)
776 #define MX21_CSPICTRL_XCH	(1 << 9)
777 #define MX21_CSPICTRL_ENABLE	(1 << 10)
778 #define MX21_CSPICTRL_MASTER	(1 << 11)
779 #define MX21_CSPICTRL_DR_SHIFT	14
780 #define MX21_CSPICTRL_CS_SHIFT	19
781 
782 static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
783 {
784 	unsigned int val = 0;
785 
786 	if (enable & MXC_INT_TE)
787 		val |= MX21_INTREG_TEEN;
788 	if (enable & MXC_INT_RR)
789 		val |= MX21_INTREG_RREN;
790 
791 	writel(val, spi_imx->base + MXC_CSPIINT);
792 }
793 
794 static void mx21_trigger(struct spi_imx_data *spi_imx)
795 {
796 	unsigned int reg;
797 
798 	reg = readl(spi_imx->base + MXC_CSPICTRL);
799 	reg |= MX21_CSPICTRL_XCH;
800 	writel(reg, spi_imx->base + MXC_CSPICTRL);
801 }
802 
803 static int mx21_prepare_message(struct spi_imx_data *spi_imx,
804 				struct spi_message *msg)
805 {
806 	return 0;
807 }
808 
809 static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
810 				 struct spi_device *spi,
811 				 struct spi_transfer *t)
812 {
813 	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
814 	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
815 	unsigned int clk;
816 
817 	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, t->speed_hz, max, &clk)
818 		<< MX21_CSPICTRL_DR_SHIFT;
819 	spi_imx->spi_bus_clk = clk;
820 
821 	reg |= spi_imx->bits_per_word - 1;
822 
823 	if (spi->mode & SPI_CPHA)
824 		reg |= MX21_CSPICTRL_PHA;
825 	if (spi->mode & SPI_CPOL)
826 		reg |= MX21_CSPICTRL_POL;
827 	if (spi->mode & SPI_CS_HIGH)
828 		reg |= MX21_CSPICTRL_SSPOL;
829 	if (!spi->cs_gpiod)
830 		reg |= spi->chip_select << MX21_CSPICTRL_CS_SHIFT;
831 
832 	writel(reg, spi_imx->base + MXC_CSPICTRL);
833 
834 	return 0;
835 }
836 
837 static int mx21_rx_available(struct spi_imx_data *spi_imx)
838 {
839 	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
840 }
841 
842 static void mx21_reset(struct spi_imx_data *spi_imx)
843 {
844 	writel(1, spi_imx->base + MXC_RESET);
845 }
846 
847 #define MX1_INTREG_RR		(1 << 3)
848 #define MX1_INTREG_TEEN		(1 << 8)
849 #define MX1_INTREG_RREN		(1 << 11)
850 
851 #define MX1_CSPICTRL_POL	(1 << 4)
852 #define MX1_CSPICTRL_PHA	(1 << 5)
853 #define MX1_CSPICTRL_XCH	(1 << 8)
854 #define MX1_CSPICTRL_ENABLE	(1 << 9)
855 #define MX1_CSPICTRL_MASTER	(1 << 10)
856 #define MX1_CSPICTRL_DR_SHIFT	13
857 
858 static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
859 {
860 	unsigned int val = 0;
861 
862 	if (enable & MXC_INT_TE)
863 		val |= MX1_INTREG_TEEN;
864 	if (enable & MXC_INT_RR)
865 		val |= MX1_INTREG_RREN;
866 
867 	writel(val, spi_imx->base + MXC_CSPIINT);
868 }
869 
870 static void mx1_trigger(struct spi_imx_data *spi_imx)
871 {
872 	unsigned int reg;
873 
874 	reg = readl(spi_imx->base + MXC_CSPICTRL);
875 	reg |= MX1_CSPICTRL_XCH;
876 	writel(reg, spi_imx->base + MXC_CSPICTRL);
877 }
878 
879 static int mx1_prepare_message(struct spi_imx_data *spi_imx,
880 			       struct spi_message *msg)
881 {
882 	return 0;
883 }
884 
885 static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
886 				struct spi_device *spi,
887 				struct spi_transfer *t)
888 {
889 	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
890 	unsigned int clk;
891 
892 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, t->speed_hz, &clk) <<
893 		MX1_CSPICTRL_DR_SHIFT;
894 	spi_imx->spi_bus_clk = clk;
895 
896 	reg |= spi_imx->bits_per_word - 1;
897 
898 	if (spi->mode & SPI_CPHA)
899 		reg |= MX1_CSPICTRL_PHA;
900 	if (spi->mode & SPI_CPOL)
901 		reg |= MX1_CSPICTRL_POL;
902 
903 	writel(reg, spi_imx->base + MXC_CSPICTRL);
904 
905 	return 0;
906 }
907 
908 static int mx1_rx_available(struct spi_imx_data *spi_imx)
909 {
910 	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
911 }
912 
913 static void mx1_reset(struct spi_imx_data *spi_imx)
914 {
915 	writel(1, spi_imx->base + MXC_RESET);
916 }
917 
918 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
919 	.intctrl = mx1_intctrl,
920 	.prepare_message = mx1_prepare_message,
921 	.prepare_transfer = mx1_prepare_transfer,
922 	.trigger = mx1_trigger,
923 	.rx_available = mx1_rx_available,
924 	.reset = mx1_reset,
925 	.fifo_size = 8,
926 	.has_dmamode = false,
927 	.dynamic_burst = false,
928 	.has_slavemode = false,
929 	.devtype = IMX1_CSPI,
930 };
931 
932 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
933 	.intctrl = mx21_intctrl,
934 	.prepare_message = mx21_prepare_message,
935 	.prepare_transfer = mx21_prepare_transfer,
936 	.trigger = mx21_trigger,
937 	.rx_available = mx21_rx_available,
938 	.reset = mx21_reset,
939 	.fifo_size = 8,
940 	.has_dmamode = false,
941 	.dynamic_burst = false,
942 	.has_slavemode = false,
943 	.devtype = IMX21_CSPI,
944 };
945 
946 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
947 	/* i.mx27 cspi shares the functions with i.mx21 one */
948 	.intctrl = mx21_intctrl,
949 	.prepare_message = mx21_prepare_message,
950 	.prepare_transfer = mx21_prepare_transfer,
951 	.trigger = mx21_trigger,
952 	.rx_available = mx21_rx_available,
953 	.reset = mx21_reset,
954 	.fifo_size = 8,
955 	.has_dmamode = false,
956 	.dynamic_burst = false,
957 	.has_slavemode = false,
958 	.devtype = IMX27_CSPI,
959 };
960 
961 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
962 	.intctrl = mx31_intctrl,
963 	.prepare_message = mx31_prepare_message,
964 	.prepare_transfer = mx31_prepare_transfer,
965 	.trigger = mx31_trigger,
966 	.rx_available = mx31_rx_available,
967 	.reset = mx31_reset,
968 	.fifo_size = 8,
969 	.has_dmamode = false,
970 	.dynamic_burst = false,
971 	.has_slavemode = false,
972 	.devtype = IMX31_CSPI,
973 };
974 
975 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
976 	/* i.mx35 and later cspi shares the functions with i.mx31 one */
977 	.intctrl = mx31_intctrl,
978 	.prepare_message = mx31_prepare_message,
979 	.prepare_transfer = mx31_prepare_transfer,
980 	.trigger = mx31_trigger,
981 	.rx_available = mx31_rx_available,
982 	.reset = mx31_reset,
983 	.fifo_size = 8,
984 	.has_dmamode = true,
985 	.dynamic_burst = false,
986 	.has_slavemode = false,
987 	.devtype = IMX35_CSPI,
988 };
989 
990 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
991 	.intctrl = mx51_ecspi_intctrl,
992 	.prepare_message = mx51_ecspi_prepare_message,
993 	.prepare_transfer = mx51_ecspi_prepare_transfer,
994 	.trigger = mx51_ecspi_trigger,
995 	.rx_available = mx51_ecspi_rx_available,
996 	.reset = mx51_ecspi_reset,
997 	.setup_wml = mx51_setup_wml,
998 	.disable_dma = mx51_disable_dma,
999 	.fifo_size = 64,
1000 	.has_dmamode = true,
1001 	.dynamic_burst = true,
1002 	.has_slavemode = true,
1003 	.disable = mx51_ecspi_disable,
1004 	.devtype = IMX51_ECSPI,
1005 };
1006 
1007 static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
1008 	.intctrl = mx51_ecspi_intctrl,
1009 	.prepare_message = mx51_ecspi_prepare_message,
1010 	.prepare_transfer = mx51_ecspi_prepare_transfer,
1011 	.trigger = mx51_ecspi_trigger,
1012 	.rx_available = mx51_ecspi_rx_available,
1013 	.disable_dma = mx51_disable_dma,
1014 	.reset = mx51_ecspi_reset,
1015 	.fifo_size = 64,
1016 	.has_dmamode = true,
1017 	.has_slavemode = true,
1018 	.disable = mx51_ecspi_disable,
1019 	.devtype = IMX53_ECSPI,
1020 };
1021 
1022 static const struct of_device_id spi_imx_dt_ids[] = {
1023 	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
1024 	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
1025 	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
1026 	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
1027 	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
1028 	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
1029 	{ .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
1030 	{ /* sentinel */ }
1031 };
1032 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
1033 
1034 static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
1035 {
1036 	u32 ctrl;
1037 
1038 	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
1039 	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
1040 	ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
1041 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
1042 }
1043 
1044 static void spi_imx_push(struct spi_imx_data *spi_imx)
1045 {
1046 	unsigned int burst_len, fifo_words;
1047 
1048 	if (spi_imx->dynamic_burst)
1049 		fifo_words = 4;
1050 	else
1051 		fifo_words = spi_imx_bytes_per_word(spi_imx->bits_per_word);
1052 	/*
1053 	 * Reload the FIFO when the remaining bytes to be transferred in the
1054 	 * current burst is 0. This only applies when bits_per_word is a
1055 	 * multiple of 8.
1056 	 */
1057 	if (!spi_imx->remainder) {
1058 		if (spi_imx->dynamic_burst) {
1059 
1060 			/* We need to deal unaligned data first */
1061 			burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
1062 
1063 			if (!burst_len)
1064 				burst_len = MX51_ECSPI_CTRL_MAX_BURST;
1065 
1066 			spi_imx_set_burst_len(spi_imx, burst_len * 8);
1067 
1068 			spi_imx->remainder = burst_len;
1069 		} else {
1070 			spi_imx->remainder = fifo_words;
1071 		}
1072 	}
1073 
1074 	while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
1075 		if (!spi_imx->count)
1076 			break;
1077 		if (spi_imx->dynamic_burst &&
1078 		    spi_imx->txfifo >= DIV_ROUND_UP(spi_imx->remainder,
1079 						     fifo_words))
1080 			break;
1081 		spi_imx->tx(spi_imx);
1082 		spi_imx->txfifo++;
1083 	}
1084 
1085 	if (!spi_imx->slave_mode)
1086 		spi_imx->devtype_data->trigger(spi_imx);
1087 }
1088 
1089 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
1090 {
1091 	struct spi_imx_data *spi_imx = dev_id;
1092 
1093 	while (spi_imx->txfifo &&
1094 	       spi_imx->devtype_data->rx_available(spi_imx)) {
1095 		spi_imx->rx(spi_imx);
1096 		spi_imx->txfifo--;
1097 	}
1098 
1099 	if (spi_imx->count) {
1100 		spi_imx_push(spi_imx);
1101 		return IRQ_HANDLED;
1102 	}
1103 
1104 	if (spi_imx->txfifo) {
1105 		/* No data left to push, but still waiting for rx data,
1106 		 * enable receive data available interrupt.
1107 		 */
1108 		spi_imx->devtype_data->intctrl(
1109 				spi_imx, MXC_INT_RR);
1110 		return IRQ_HANDLED;
1111 	}
1112 
1113 	spi_imx->devtype_data->intctrl(spi_imx, 0);
1114 	complete(&spi_imx->xfer_done);
1115 
1116 	return IRQ_HANDLED;
1117 }
1118 
1119 static int spi_imx_dma_configure(struct spi_master *master)
1120 {
1121 	int ret;
1122 	enum dma_slave_buswidth buswidth;
1123 	struct dma_slave_config rx = {}, tx = {};
1124 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1125 
1126 	switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
1127 	case 4:
1128 		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
1129 		break;
1130 	case 2:
1131 		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
1132 		break;
1133 	case 1:
1134 		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
1135 		break;
1136 	default:
1137 		return -EINVAL;
1138 	}
1139 
1140 	tx.direction = DMA_MEM_TO_DEV;
1141 	tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
1142 	tx.dst_addr_width = buswidth;
1143 	tx.dst_maxburst = spi_imx->wml;
1144 	ret = dmaengine_slave_config(master->dma_tx, &tx);
1145 	if (ret) {
1146 		dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
1147 		return ret;
1148 	}
1149 
1150 	rx.direction = DMA_DEV_TO_MEM;
1151 	rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
1152 	rx.src_addr_width = buswidth;
1153 	rx.src_maxburst = spi_imx->wml;
1154 	ret = dmaengine_slave_config(master->dma_rx, &rx);
1155 	if (ret) {
1156 		dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
1157 		return ret;
1158 	}
1159 
1160 	return 0;
1161 }
1162 
1163 static int spi_imx_setupxfer(struct spi_device *spi,
1164 				 struct spi_transfer *t)
1165 {
1166 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1167 
1168 	if (!t)
1169 		return 0;
1170 
1171 	spi_imx->bits_per_word = t->bits_per_word;
1172 
1173 	/*
1174 	 * Initialize the functions for transfer. To transfer non byte-aligned
1175 	 * words, we have to use multiple word-size bursts, we can't use
1176 	 * dynamic_burst in that case.
1177 	 */
1178 	if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode &&
1179 	    (spi_imx->bits_per_word == 8 ||
1180 	    spi_imx->bits_per_word == 16 ||
1181 	    spi_imx->bits_per_word == 32)) {
1182 
1183 		spi_imx->rx = spi_imx_buf_rx_swap;
1184 		spi_imx->tx = spi_imx_buf_tx_swap;
1185 		spi_imx->dynamic_burst = 1;
1186 
1187 	} else {
1188 		if (spi_imx->bits_per_word <= 8) {
1189 			spi_imx->rx = spi_imx_buf_rx_u8;
1190 			spi_imx->tx = spi_imx_buf_tx_u8;
1191 		} else if (spi_imx->bits_per_word <= 16) {
1192 			spi_imx->rx = spi_imx_buf_rx_u16;
1193 			spi_imx->tx = spi_imx_buf_tx_u16;
1194 		} else {
1195 			spi_imx->rx = spi_imx_buf_rx_u32;
1196 			spi_imx->tx = spi_imx_buf_tx_u32;
1197 		}
1198 		spi_imx->dynamic_burst = 0;
1199 	}
1200 
1201 	if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
1202 		spi_imx->usedma = true;
1203 	else
1204 		spi_imx->usedma = false;
1205 
1206 	if (is_imx53_ecspi(spi_imx) && spi_imx->slave_mode) {
1207 		spi_imx->rx = mx53_ecspi_rx_slave;
1208 		spi_imx->tx = mx53_ecspi_tx_slave;
1209 		spi_imx->slave_burst = t->len;
1210 	}
1211 
1212 	spi_imx->devtype_data->prepare_transfer(spi_imx, spi, t);
1213 
1214 	return 0;
1215 }
1216 
1217 static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
1218 {
1219 	struct spi_master *master = spi_imx->bitbang.master;
1220 
1221 	if (master->dma_rx) {
1222 		dma_release_channel(master->dma_rx);
1223 		master->dma_rx = NULL;
1224 	}
1225 
1226 	if (master->dma_tx) {
1227 		dma_release_channel(master->dma_tx);
1228 		master->dma_tx = NULL;
1229 	}
1230 }
1231 
1232 static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
1233 			     struct spi_master *master)
1234 {
1235 	int ret;
1236 
1237 	/* use pio mode for i.mx6dl chip TKT238285 */
1238 	if (of_machine_is_compatible("fsl,imx6dl"))
1239 		return 0;
1240 
1241 	spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
1242 
1243 	/* Prepare for TX DMA: */
1244 	master->dma_tx = dma_request_chan(dev, "tx");
1245 	if (IS_ERR(master->dma_tx)) {
1246 		ret = PTR_ERR(master->dma_tx);
1247 		dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
1248 		master->dma_tx = NULL;
1249 		goto err;
1250 	}
1251 
1252 	/* Prepare for RX : */
1253 	master->dma_rx = dma_request_chan(dev, "rx");
1254 	if (IS_ERR(master->dma_rx)) {
1255 		ret = PTR_ERR(master->dma_rx);
1256 		dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
1257 		master->dma_rx = NULL;
1258 		goto err;
1259 	}
1260 
1261 	init_completion(&spi_imx->dma_rx_completion);
1262 	init_completion(&spi_imx->dma_tx_completion);
1263 	master->can_dma = spi_imx_can_dma;
1264 	master->max_dma_len = MAX_SDMA_BD_BYTES;
1265 	spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
1266 					 SPI_MASTER_MUST_TX;
1267 
1268 	return 0;
1269 err:
1270 	spi_imx_sdma_exit(spi_imx);
1271 	return ret;
1272 }
1273 
1274 static void spi_imx_dma_rx_callback(void *cookie)
1275 {
1276 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1277 
1278 	complete(&spi_imx->dma_rx_completion);
1279 }
1280 
1281 static void spi_imx_dma_tx_callback(void *cookie)
1282 {
1283 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1284 
1285 	complete(&spi_imx->dma_tx_completion);
1286 }
1287 
1288 static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1289 {
1290 	unsigned long timeout = 0;
1291 
1292 	/* Time with actual data transfer and CS change delay related to HW */
1293 	timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1294 
1295 	/* Add extra second for scheduler related activities */
1296 	timeout += 1;
1297 
1298 	/* Double calculated timeout */
1299 	return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1300 }
1301 
1302 static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1303 				struct spi_transfer *transfer)
1304 {
1305 	struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1306 	unsigned long transfer_timeout;
1307 	unsigned long timeout;
1308 	struct spi_master *master = spi_imx->bitbang.master;
1309 	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1310 	struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
1311 	unsigned int bytes_per_word, i;
1312 	int ret;
1313 
1314 	/* Get the right burst length from the last sg to ensure no tail data */
1315 	bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
1316 	for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
1317 		if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
1318 			break;
1319 	}
1320 	/* Use 1 as wml in case no available burst length got */
1321 	if (i == 0)
1322 		i = 1;
1323 
1324 	spi_imx->wml =  i;
1325 
1326 	ret = spi_imx_dma_configure(master);
1327 	if (ret)
1328 		goto dma_failure_no_start;
1329 
1330 	if (!spi_imx->devtype_data->setup_wml) {
1331 		dev_err(spi_imx->dev, "No setup_wml()?\n");
1332 		ret = -EINVAL;
1333 		goto dma_failure_no_start;
1334 	}
1335 	spi_imx->devtype_data->setup_wml(spi_imx);
1336 
1337 	/*
1338 	 * The TX DMA setup starts the transfer, so make sure RX is configured
1339 	 * before TX.
1340 	 */
1341 	desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
1342 				rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1343 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1344 	if (!desc_rx) {
1345 		ret = -EINVAL;
1346 		goto dma_failure_no_start;
1347 	}
1348 
1349 	desc_rx->callback = spi_imx_dma_rx_callback;
1350 	desc_rx->callback_param = (void *)spi_imx;
1351 	dmaengine_submit(desc_rx);
1352 	reinit_completion(&spi_imx->dma_rx_completion);
1353 	dma_async_issue_pending(master->dma_rx);
1354 
1355 	desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
1356 				tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1357 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1358 	if (!desc_tx) {
1359 		dmaengine_terminate_all(master->dma_tx);
1360 		dmaengine_terminate_all(master->dma_rx);
1361 		return -EINVAL;
1362 	}
1363 
1364 	desc_tx->callback = spi_imx_dma_tx_callback;
1365 	desc_tx->callback_param = (void *)spi_imx;
1366 	dmaengine_submit(desc_tx);
1367 	reinit_completion(&spi_imx->dma_tx_completion);
1368 	dma_async_issue_pending(master->dma_tx);
1369 
1370 	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1371 
1372 	/* Wait SDMA to finish the data transfer.*/
1373 	timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1374 						transfer_timeout);
1375 	if (!timeout) {
1376 		dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1377 		dmaengine_terminate_all(master->dma_tx);
1378 		dmaengine_terminate_all(master->dma_rx);
1379 		return -ETIMEDOUT;
1380 	}
1381 
1382 	timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1383 					      transfer_timeout);
1384 	if (!timeout) {
1385 		dev_err(&master->dev, "I/O Error in DMA RX\n");
1386 		spi_imx->devtype_data->reset(spi_imx);
1387 		dmaengine_terminate_all(master->dma_rx);
1388 		return -ETIMEDOUT;
1389 	}
1390 
1391 	return transfer->len;
1392 /* fallback to pio */
1393 dma_failure_no_start:
1394 	transfer->error |= SPI_TRANS_FAIL_NO_START;
1395 	return ret;
1396 }
1397 
1398 static int spi_imx_pio_transfer(struct spi_device *spi,
1399 				struct spi_transfer *transfer)
1400 {
1401 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1402 	unsigned long transfer_timeout;
1403 	unsigned long timeout;
1404 
1405 	spi_imx->tx_buf = transfer->tx_buf;
1406 	spi_imx->rx_buf = transfer->rx_buf;
1407 	spi_imx->count = transfer->len;
1408 	spi_imx->txfifo = 0;
1409 	spi_imx->remainder = 0;
1410 
1411 	reinit_completion(&spi_imx->xfer_done);
1412 
1413 	spi_imx_push(spi_imx);
1414 
1415 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1416 
1417 	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1418 
1419 	timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
1420 					      transfer_timeout);
1421 	if (!timeout) {
1422 		dev_err(&spi->dev, "I/O Error in PIO\n");
1423 		spi_imx->devtype_data->reset(spi_imx);
1424 		return -ETIMEDOUT;
1425 	}
1426 
1427 	return transfer->len;
1428 }
1429 
1430 static int spi_imx_pio_transfer_slave(struct spi_device *spi,
1431 				      struct spi_transfer *transfer)
1432 {
1433 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1434 	int ret = transfer->len;
1435 
1436 	if (is_imx53_ecspi(spi_imx) &&
1437 	    transfer->len > MX53_MAX_TRANSFER_BYTES) {
1438 		dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
1439 			MX53_MAX_TRANSFER_BYTES);
1440 		return -EMSGSIZE;
1441 	}
1442 
1443 	spi_imx->tx_buf = transfer->tx_buf;
1444 	spi_imx->rx_buf = transfer->rx_buf;
1445 	spi_imx->count = transfer->len;
1446 	spi_imx->txfifo = 0;
1447 	spi_imx->remainder = 0;
1448 
1449 	reinit_completion(&spi_imx->xfer_done);
1450 	spi_imx->slave_aborted = false;
1451 
1452 	spi_imx_push(spi_imx);
1453 
1454 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
1455 
1456 	if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
1457 	    spi_imx->slave_aborted) {
1458 		dev_dbg(&spi->dev, "interrupted\n");
1459 		ret = -EINTR;
1460 	}
1461 
1462 	/* ecspi has a HW issue when works in Slave mode,
1463 	 * after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
1464 	 * ECSPI_TXDATA keeps shift out the last word data,
1465 	 * so we have to disable ECSPI when in slave mode after the
1466 	 * transfer completes
1467 	 */
1468 	if (spi_imx->devtype_data->disable)
1469 		spi_imx->devtype_data->disable(spi_imx);
1470 
1471 	return ret;
1472 }
1473 
1474 static int spi_imx_transfer(struct spi_device *spi,
1475 				struct spi_transfer *transfer)
1476 {
1477 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1478 
1479 	transfer->effective_speed_hz = spi_imx->spi_bus_clk;
1480 
1481 	/* flush rxfifo before transfer */
1482 	while (spi_imx->devtype_data->rx_available(spi_imx))
1483 		readl(spi_imx->base + MXC_CSPIRXDATA);
1484 
1485 	if (spi_imx->slave_mode)
1486 		return spi_imx_pio_transfer_slave(spi, transfer);
1487 
1488 	if (spi_imx->usedma)
1489 		return spi_imx_dma_transfer(spi_imx, transfer);
1490 
1491 	return spi_imx_pio_transfer(spi, transfer);
1492 }
1493 
1494 static int spi_imx_setup(struct spi_device *spi)
1495 {
1496 	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1497 		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1498 
1499 	return 0;
1500 }
1501 
1502 static void spi_imx_cleanup(struct spi_device *spi)
1503 {
1504 }
1505 
1506 static int
1507 spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1508 {
1509 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1510 	int ret;
1511 
1512 	ret = pm_runtime_get_sync(spi_imx->dev);
1513 	if (ret < 0) {
1514 		pm_runtime_put_noidle(spi_imx->dev);
1515 		dev_err(spi_imx->dev, "failed to enable clock\n");
1516 		return ret;
1517 	}
1518 
1519 	ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
1520 	if (ret) {
1521 		pm_runtime_mark_last_busy(spi_imx->dev);
1522 		pm_runtime_put_autosuspend(spi_imx->dev);
1523 	}
1524 
1525 	return ret;
1526 }
1527 
1528 static int
1529 spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1530 {
1531 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1532 
1533 	pm_runtime_mark_last_busy(spi_imx->dev);
1534 	pm_runtime_put_autosuspend(spi_imx->dev);
1535 	return 0;
1536 }
1537 
1538 static int spi_imx_slave_abort(struct spi_master *master)
1539 {
1540 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1541 
1542 	spi_imx->slave_aborted = true;
1543 	complete(&spi_imx->xfer_done);
1544 
1545 	return 0;
1546 }
1547 
1548 static int spi_imx_probe(struct platform_device *pdev)
1549 {
1550 	struct device_node *np = pdev->dev.of_node;
1551 	const struct of_device_id *of_id =
1552 			of_match_device(spi_imx_dt_ids, &pdev->dev);
1553 	struct spi_master *master;
1554 	struct spi_imx_data *spi_imx;
1555 	struct resource *res;
1556 	int ret, irq, spi_drctl;
1557 	const struct spi_imx_devtype_data *devtype_data = of_id->data;
1558 	bool slave_mode;
1559 	u32 val;
1560 
1561 	slave_mode = devtype_data->has_slavemode &&
1562 			of_property_read_bool(np, "spi-slave");
1563 	if (slave_mode)
1564 		master = spi_alloc_slave(&pdev->dev,
1565 					 sizeof(struct spi_imx_data));
1566 	else
1567 		master = spi_alloc_master(&pdev->dev,
1568 					  sizeof(struct spi_imx_data));
1569 	if (!master)
1570 		return -ENOMEM;
1571 
1572 	ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
1573 	if ((ret < 0) || (spi_drctl >= 0x3)) {
1574 		/* '11' is reserved */
1575 		spi_drctl = 0;
1576 	}
1577 
1578 	platform_set_drvdata(pdev, master);
1579 
1580 	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1581 	master->bus_num = np ? -1 : pdev->id;
1582 	master->use_gpio_descriptors = true;
1583 
1584 	spi_imx = spi_master_get_devdata(master);
1585 	spi_imx->bitbang.master = master;
1586 	spi_imx->dev = &pdev->dev;
1587 	spi_imx->slave_mode = slave_mode;
1588 
1589 	spi_imx->devtype_data = devtype_data;
1590 
1591 	/*
1592 	 * Get number of chip selects from device properties. This can be
1593 	 * coming from device tree or boardfiles, if it is not defined,
1594 	 * a default value of 3 chip selects will be used, as all the legacy
1595 	 * board files have <= 3 chip selects.
1596 	 */
1597 	if (!device_property_read_u32(&pdev->dev, "num-cs", &val))
1598 		master->num_chipselect = val;
1599 	else
1600 		master->num_chipselect = 3;
1601 
1602 	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1603 	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1604 	spi_imx->bitbang.master->setup = spi_imx_setup;
1605 	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1606 	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1607 	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1608 	spi_imx->bitbang.master->slave_abort = spi_imx_slave_abort;
1609 	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
1610 					     | SPI_NO_CS;
1611 	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
1612 	    is_imx53_ecspi(spi_imx))
1613 		spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY;
1614 
1615 	spi_imx->spi_drctl = spi_drctl;
1616 
1617 	init_completion(&spi_imx->xfer_done);
1618 
1619 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1620 	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1621 	if (IS_ERR(spi_imx->base)) {
1622 		ret = PTR_ERR(spi_imx->base);
1623 		goto out_master_put;
1624 	}
1625 	spi_imx->base_phys = res->start;
1626 
1627 	irq = platform_get_irq(pdev, 0);
1628 	if (irq < 0) {
1629 		ret = irq;
1630 		goto out_master_put;
1631 	}
1632 
1633 	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1634 			       dev_name(&pdev->dev), spi_imx);
1635 	if (ret) {
1636 		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1637 		goto out_master_put;
1638 	}
1639 
1640 	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1641 	if (IS_ERR(spi_imx->clk_ipg)) {
1642 		ret = PTR_ERR(spi_imx->clk_ipg);
1643 		goto out_master_put;
1644 	}
1645 
1646 	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1647 	if (IS_ERR(spi_imx->clk_per)) {
1648 		ret = PTR_ERR(spi_imx->clk_per);
1649 		goto out_master_put;
1650 	}
1651 
1652 	ret = clk_prepare_enable(spi_imx->clk_per);
1653 	if (ret)
1654 		goto out_master_put;
1655 
1656 	ret = clk_prepare_enable(spi_imx->clk_ipg);
1657 	if (ret)
1658 		goto out_put_per;
1659 
1660 	pm_runtime_set_autosuspend_delay(spi_imx->dev, MXC_RPM_TIMEOUT);
1661 	pm_runtime_use_autosuspend(spi_imx->dev);
1662 	pm_runtime_get_noresume(spi_imx->dev);
1663 	pm_runtime_set_active(spi_imx->dev);
1664 	pm_runtime_enable(spi_imx->dev);
1665 
1666 	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1667 	/*
1668 	 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1669 	 * if validated on other chips.
1670 	 */
1671 	if (spi_imx->devtype_data->has_dmamode) {
1672 		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
1673 		if (ret == -EPROBE_DEFER)
1674 			goto out_runtime_pm_put;
1675 
1676 		if (ret < 0)
1677 			dev_dbg(&pdev->dev, "dma setup error %d, use pio\n",
1678 				ret);
1679 	}
1680 
1681 	spi_imx->devtype_data->reset(spi_imx);
1682 
1683 	spi_imx->devtype_data->intctrl(spi_imx, 0);
1684 
1685 	master->dev.of_node = pdev->dev.of_node;
1686 	ret = spi_bitbang_start(&spi_imx->bitbang);
1687 	if (ret) {
1688 		dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
1689 		goto out_bitbang_start;
1690 	}
1691 
1692 	pm_runtime_mark_last_busy(spi_imx->dev);
1693 	pm_runtime_put_autosuspend(spi_imx->dev);
1694 
1695 	return ret;
1696 
1697 out_bitbang_start:
1698 	if (spi_imx->devtype_data->has_dmamode)
1699 		spi_imx_sdma_exit(spi_imx);
1700 out_runtime_pm_put:
1701 	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1702 	pm_runtime_set_suspended(&pdev->dev);
1703 	pm_runtime_disable(spi_imx->dev);
1704 
1705 	clk_disable_unprepare(spi_imx->clk_ipg);
1706 out_put_per:
1707 	clk_disable_unprepare(spi_imx->clk_per);
1708 out_master_put:
1709 	spi_master_put(master);
1710 
1711 	return ret;
1712 }
1713 
1714 static int spi_imx_remove(struct platform_device *pdev)
1715 {
1716 	struct spi_master *master = platform_get_drvdata(pdev);
1717 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1718 	int ret;
1719 
1720 	spi_bitbang_stop(&spi_imx->bitbang);
1721 
1722 	ret = pm_runtime_get_sync(spi_imx->dev);
1723 	if (ret < 0) {
1724 		pm_runtime_put_noidle(spi_imx->dev);
1725 		dev_err(spi_imx->dev, "failed to enable clock\n");
1726 		return ret;
1727 	}
1728 
1729 	writel(0, spi_imx->base + MXC_CSPICTRL);
1730 
1731 	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1732 	pm_runtime_put_sync(spi_imx->dev);
1733 	pm_runtime_disable(spi_imx->dev);
1734 
1735 	spi_imx_sdma_exit(spi_imx);
1736 	spi_master_put(master);
1737 
1738 	return 0;
1739 }
1740 
1741 static int __maybe_unused spi_imx_runtime_resume(struct device *dev)
1742 {
1743 	struct spi_master *master = dev_get_drvdata(dev);
1744 	struct spi_imx_data *spi_imx;
1745 	int ret;
1746 
1747 	spi_imx = spi_master_get_devdata(master);
1748 
1749 	ret = clk_prepare_enable(spi_imx->clk_per);
1750 	if (ret)
1751 		return ret;
1752 
1753 	ret = clk_prepare_enable(spi_imx->clk_ipg);
1754 	if (ret) {
1755 		clk_disable_unprepare(spi_imx->clk_per);
1756 		return ret;
1757 	}
1758 
1759 	return 0;
1760 }
1761 
1762 static int __maybe_unused spi_imx_runtime_suspend(struct device *dev)
1763 {
1764 	struct spi_master *master = dev_get_drvdata(dev);
1765 	struct spi_imx_data *spi_imx;
1766 
1767 	spi_imx = spi_master_get_devdata(master);
1768 
1769 	clk_disable_unprepare(spi_imx->clk_per);
1770 	clk_disable_unprepare(spi_imx->clk_ipg);
1771 
1772 	return 0;
1773 }
1774 
1775 static int __maybe_unused spi_imx_suspend(struct device *dev)
1776 {
1777 	pinctrl_pm_select_sleep_state(dev);
1778 	return 0;
1779 }
1780 
1781 static int __maybe_unused spi_imx_resume(struct device *dev)
1782 {
1783 	pinctrl_pm_select_default_state(dev);
1784 	return 0;
1785 }
1786 
1787 static const struct dev_pm_ops imx_spi_pm = {
1788 	SET_RUNTIME_PM_OPS(spi_imx_runtime_suspend,
1789 				spi_imx_runtime_resume, NULL)
1790 	SET_SYSTEM_SLEEP_PM_OPS(spi_imx_suspend, spi_imx_resume)
1791 };
1792 
1793 static struct platform_driver spi_imx_driver = {
1794 	.driver = {
1795 		   .name = DRIVER_NAME,
1796 		   .of_match_table = spi_imx_dt_ids,
1797 		   .pm = &imx_spi_pm,
1798 	},
1799 	.probe = spi_imx_probe,
1800 	.remove = spi_imx_remove,
1801 };
1802 module_platform_driver(spi_imx_driver);
1803 
1804 MODULE_DESCRIPTION("SPI Controller driver");
1805 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1806 MODULE_LICENSE("GPL");
1807 MODULE_ALIAS("platform:" DRIVER_NAME);
1808