xref: /linux/drivers/spi/spi-imx.c (revision 920c293af8d01942caa10300ad97eabf778e8598)
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 	struct spi_transfer *xfer;
509 	u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
510 	u32 min_speed_hz = ~0U;
511 	u32 testreg, delay;
512 	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
513 
514 	/* set Master or Slave mode */
515 	if (spi_imx->slave_mode)
516 		ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
517 	else
518 		ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
519 
520 	/*
521 	 * Enable SPI_RDY handling (falling edge/level triggered).
522 	 */
523 	if (spi->mode & SPI_READY)
524 		ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
525 
526 	/* set chip select to use */
527 	ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
528 
529 	/*
530 	 * The ctrl register must be written first, with the EN bit set other
531 	 * registers must not be written to.
532 	 */
533 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
534 
535 	testreg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
536 	if (spi->mode & SPI_LOOP)
537 		testreg |= MX51_ECSPI_TESTREG_LBC;
538 	else
539 		testreg &= ~MX51_ECSPI_TESTREG_LBC;
540 	writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
541 
542 	/*
543 	 * eCSPI burst completion by Chip Select signal in Slave mode
544 	 * is not functional for imx53 Soc, config SPI burst completed when
545 	 * BURST_LENGTH + 1 bits are received
546 	 */
547 	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
548 		cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
549 	else
550 		cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
551 
552 	if (spi->mode & SPI_CPHA)
553 		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
554 	else
555 		cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
556 
557 	if (spi->mode & SPI_CPOL) {
558 		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
559 		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
560 	} else {
561 		cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
562 		cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
563 	}
564 
565 	if (spi->mode & SPI_CS_HIGH)
566 		cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
567 	else
568 		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
569 
570 	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
571 
572 	/*
573 	 * Wait until the changes in the configuration register CONFIGREG
574 	 * propagate into the hardware. It takes exactly one tick of the
575 	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
576 	 * effect of the delay it takes for the hardware to apply changes
577 	 * is noticable if the SCLK clock run very slow. In such a case, if
578 	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
579 	 * be asserted before the SCLK polarity changes, which would disrupt
580 	 * the SPI communication as the device on the other end would consider
581 	 * the change of SCLK polarity as a clock tick already.
582 	 *
583 	 * Because spi_imx->spi_bus_clk is only set in bitbang prepare_message
584 	 * callback, iterate over all the transfers in spi_message, find the
585 	 * one with lowest bus frequency, and use that bus frequency for the
586 	 * delay calculation. In case all transfers have speed_hz == 0, then
587 	 * min_speed_hz is ~0 and the resulting delay is zero.
588 	 */
589 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
590 		if (!xfer->speed_hz)
591 			continue;
592 		min_speed_hz = min(xfer->speed_hz, min_speed_hz);
593 	}
594 
595 	delay = (2 * 1000000) / min_speed_hz;
596 	if (likely(delay < 10))	/* SCLK is faster than 200 kHz */
597 		udelay(delay);
598 	else			/* SCLK is _very_ slow */
599 		usleep_range(delay, delay + 10);
600 
601 	return 0;
602 }
603 
604 static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
605 				       struct spi_device *spi)
606 {
607 	u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
608 	u32 clk;
609 
610 	/* Clear BL field and set the right value */
611 	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
612 	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
613 		ctrl |= (spi_imx->slave_burst * 8 - 1)
614 			<< MX51_ECSPI_CTRL_BL_OFFSET;
615 	else
616 		ctrl |= (spi_imx->bits_per_word - 1)
617 			<< MX51_ECSPI_CTRL_BL_OFFSET;
618 
619 	/* set clock speed */
620 	ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
621 		  0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
622 	ctrl |= mx51_ecspi_clkdiv(spi_imx, spi_imx->spi_bus_clk, &clk);
623 	spi_imx->spi_bus_clk = clk;
624 
625 	if (spi_imx->usedma)
626 		ctrl |= MX51_ECSPI_CTRL_SMC;
627 
628 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
629 
630 	return 0;
631 }
632 
633 static void mx51_setup_wml(struct spi_imx_data *spi_imx)
634 {
635 	/*
636 	 * Configure the DMA register: setup the watermark
637 	 * and enable DMA request.
638 	 */
639 	writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) |
640 		MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
641 		MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
642 		MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
643 		MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
644 }
645 
646 static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
647 {
648 	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
649 }
650 
651 static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
652 {
653 	/* drain receive buffer */
654 	while (mx51_ecspi_rx_available(spi_imx))
655 		readl(spi_imx->base + MXC_CSPIRXDATA);
656 }
657 
658 #define MX31_INTREG_TEEN	(1 << 0)
659 #define MX31_INTREG_RREN	(1 << 3)
660 
661 #define MX31_CSPICTRL_ENABLE	(1 << 0)
662 #define MX31_CSPICTRL_MASTER	(1 << 1)
663 #define MX31_CSPICTRL_XCH	(1 << 2)
664 #define MX31_CSPICTRL_SMC	(1 << 3)
665 #define MX31_CSPICTRL_POL	(1 << 4)
666 #define MX31_CSPICTRL_PHA	(1 << 5)
667 #define MX31_CSPICTRL_SSCTL	(1 << 6)
668 #define MX31_CSPICTRL_SSPOL	(1 << 7)
669 #define MX31_CSPICTRL_BC_SHIFT	8
670 #define MX35_CSPICTRL_BL_SHIFT	20
671 #define MX31_CSPICTRL_CS_SHIFT	24
672 #define MX35_CSPICTRL_CS_SHIFT	12
673 #define MX31_CSPICTRL_DR_SHIFT	16
674 
675 #define MX31_CSPI_DMAREG	0x10
676 #define MX31_DMAREG_RH_DEN	(1<<4)
677 #define MX31_DMAREG_TH_DEN	(1<<1)
678 
679 #define MX31_CSPISTATUS		0x14
680 #define MX31_STATUS_RR		(1 << 3)
681 
682 #define MX31_CSPI_TESTREG	0x1C
683 #define MX31_TEST_LBC		(1 << 14)
684 
685 /* These functions also work for the i.MX35, but be aware that
686  * the i.MX35 has a slightly different register layout for bits
687  * we do not use here.
688  */
689 static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
690 {
691 	unsigned int val = 0;
692 
693 	if (enable & MXC_INT_TE)
694 		val |= MX31_INTREG_TEEN;
695 	if (enable & MXC_INT_RR)
696 		val |= MX31_INTREG_RREN;
697 
698 	writel(val, spi_imx->base + MXC_CSPIINT);
699 }
700 
701 static void mx31_trigger(struct spi_imx_data *spi_imx)
702 {
703 	unsigned int reg;
704 
705 	reg = readl(spi_imx->base + MXC_CSPICTRL);
706 	reg |= MX31_CSPICTRL_XCH;
707 	writel(reg, spi_imx->base + MXC_CSPICTRL);
708 }
709 
710 static int mx31_prepare_message(struct spi_imx_data *spi_imx,
711 				struct spi_message *msg)
712 {
713 	return 0;
714 }
715 
716 static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
717 				 struct spi_device *spi)
718 {
719 	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
720 	unsigned int clk;
721 
722 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
723 		MX31_CSPICTRL_DR_SHIFT;
724 	spi_imx->spi_bus_clk = clk;
725 
726 	if (is_imx35_cspi(spi_imx)) {
727 		reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
728 		reg |= MX31_CSPICTRL_SSCTL;
729 	} else {
730 		reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
731 	}
732 
733 	if (spi->mode & SPI_CPHA)
734 		reg |= MX31_CSPICTRL_PHA;
735 	if (spi->mode & SPI_CPOL)
736 		reg |= MX31_CSPICTRL_POL;
737 	if (spi->mode & SPI_CS_HIGH)
738 		reg |= MX31_CSPICTRL_SSPOL;
739 	if (!spi->cs_gpiod)
740 		reg |= (spi->chip_select) <<
741 			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
742 						  MX31_CSPICTRL_CS_SHIFT);
743 
744 	if (spi_imx->usedma)
745 		reg |= MX31_CSPICTRL_SMC;
746 
747 	writel(reg, spi_imx->base + MXC_CSPICTRL);
748 
749 	reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
750 	if (spi->mode & SPI_LOOP)
751 		reg |= MX31_TEST_LBC;
752 	else
753 		reg &= ~MX31_TEST_LBC;
754 	writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
755 
756 	if (spi_imx->usedma) {
757 		/*
758 		 * configure DMA requests when RXFIFO is half full and
759 		 * when TXFIFO is half empty
760 		 */
761 		writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
762 			spi_imx->base + MX31_CSPI_DMAREG);
763 	}
764 
765 	return 0;
766 }
767 
768 static int mx31_rx_available(struct spi_imx_data *spi_imx)
769 {
770 	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
771 }
772 
773 static void mx31_reset(struct spi_imx_data *spi_imx)
774 {
775 	/* drain receive buffer */
776 	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
777 		readl(spi_imx->base + MXC_CSPIRXDATA);
778 }
779 
780 #define MX21_INTREG_RR		(1 << 4)
781 #define MX21_INTREG_TEEN	(1 << 9)
782 #define MX21_INTREG_RREN	(1 << 13)
783 
784 #define MX21_CSPICTRL_POL	(1 << 5)
785 #define MX21_CSPICTRL_PHA	(1 << 6)
786 #define MX21_CSPICTRL_SSPOL	(1 << 8)
787 #define MX21_CSPICTRL_XCH	(1 << 9)
788 #define MX21_CSPICTRL_ENABLE	(1 << 10)
789 #define MX21_CSPICTRL_MASTER	(1 << 11)
790 #define MX21_CSPICTRL_DR_SHIFT	14
791 #define MX21_CSPICTRL_CS_SHIFT	19
792 
793 static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
794 {
795 	unsigned int val = 0;
796 
797 	if (enable & MXC_INT_TE)
798 		val |= MX21_INTREG_TEEN;
799 	if (enable & MXC_INT_RR)
800 		val |= MX21_INTREG_RREN;
801 
802 	writel(val, spi_imx->base + MXC_CSPIINT);
803 }
804 
805 static void mx21_trigger(struct spi_imx_data *spi_imx)
806 {
807 	unsigned int reg;
808 
809 	reg = readl(spi_imx->base + MXC_CSPICTRL);
810 	reg |= MX21_CSPICTRL_XCH;
811 	writel(reg, spi_imx->base + MXC_CSPICTRL);
812 }
813 
814 static int mx21_prepare_message(struct spi_imx_data *spi_imx,
815 				struct spi_message *msg)
816 {
817 	return 0;
818 }
819 
820 static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
821 				 struct spi_device *spi)
822 {
823 	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
824 	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
825 	unsigned int clk;
826 
827 	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, spi_imx->spi_bus_clk, max, &clk)
828 		<< MX21_CSPICTRL_DR_SHIFT;
829 	spi_imx->spi_bus_clk = clk;
830 
831 	reg |= spi_imx->bits_per_word - 1;
832 
833 	if (spi->mode & SPI_CPHA)
834 		reg |= MX21_CSPICTRL_PHA;
835 	if (spi->mode & SPI_CPOL)
836 		reg |= MX21_CSPICTRL_POL;
837 	if (spi->mode & SPI_CS_HIGH)
838 		reg |= MX21_CSPICTRL_SSPOL;
839 	if (!spi->cs_gpiod)
840 		reg |= spi->chip_select << MX21_CSPICTRL_CS_SHIFT;
841 
842 	writel(reg, spi_imx->base + MXC_CSPICTRL);
843 
844 	return 0;
845 }
846 
847 static int mx21_rx_available(struct spi_imx_data *spi_imx)
848 {
849 	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
850 }
851 
852 static void mx21_reset(struct spi_imx_data *spi_imx)
853 {
854 	writel(1, spi_imx->base + MXC_RESET);
855 }
856 
857 #define MX1_INTREG_RR		(1 << 3)
858 #define MX1_INTREG_TEEN		(1 << 8)
859 #define MX1_INTREG_RREN		(1 << 11)
860 
861 #define MX1_CSPICTRL_POL	(1 << 4)
862 #define MX1_CSPICTRL_PHA	(1 << 5)
863 #define MX1_CSPICTRL_XCH	(1 << 8)
864 #define MX1_CSPICTRL_ENABLE	(1 << 9)
865 #define MX1_CSPICTRL_MASTER	(1 << 10)
866 #define MX1_CSPICTRL_DR_SHIFT	13
867 
868 static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
869 {
870 	unsigned int val = 0;
871 
872 	if (enable & MXC_INT_TE)
873 		val |= MX1_INTREG_TEEN;
874 	if (enable & MXC_INT_RR)
875 		val |= MX1_INTREG_RREN;
876 
877 	writel(val, spi_imx->base + MXC_CSPIINT);
878 }
879 
880 static void mx1_trigger(struct spi_imx_data *spi_imx)
881 {
882 	unsigned int reg;
883 
884 	reg = readl(spi_imx->base + MXC_CSPICTRL);
885 	reg |= MX1_CSPICTRL_XCH;
886 	writel(reg, spi_imx->base + MXC_CSPICTRL);
887 }
888 
889 static int mx1_prepare_message(struct spi_imx_data *spi_imx,
890 			       struct spi_message *msg)
891 {
892 	return 0;
893 }
894 
895 static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
896 				struct spi_device *spi)
897 {
898 	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
899 	unsigned int clk;
900 
901 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
902 		MX1_CSPICTRL_DR_SHIFT;
903 	spi_imx->spi_bus_clk = clk;
904 
905 	reg |= spi_imx->bits_per_word - 1;
906 
907 	if (spi->mode & SPI_CPHA)
908 		reg |= MX1_CSPICTRL_PHA;
909 	if (spi->mode & SPI_CPOL)
910 		reg |= MX1_CSPICTRL_POL;
911 
912 	writel(reg, spi_imx->base + MXC_CSPICTRL);
913 
914 	return 0;
915 }
916 
917 static int mx1_rx_available(struct spi_imx_data *spi_imx)
918 {
919 	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
920 }
921 
922 static void mx1_reset(struct spi_imx_data *spi_imx)
923 {
924 	writel(1, spi_imx->base + MXC_RESET);
925 }
926 
927 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
928 	.intctrl = mx1_intctrl,
929 	.prepare_message = mx1_prepare_message,
930 	.prepare_transfer = mx1_prepare_transfer,
931 	.trigger = mx1_trigger,
932 	.rx_available = mx1_rx_available,
933 	.reset = mx1_reset,
934 	.fifo_size = 8,
935 	.has_dmamode = false,
936 	.dynamic_burst = false,
937 	.has_slavemode = false,
938 	.devtype = IMX1_CSPI,
939 };
940 
941 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
942 	.intctrl = mx21_intctrl,
943 	.prepare_message = mx21_prepare_message,
944 	.prepare_transfer = mx21_prepare_transfer,
945 	.trigger = mx21_trigger,
946 	.rx_available = mx21_rx_available,
947 	.reset = mx21_reset,
948 	.fifo_size = 8,
949 	.has_dmamode = false,
950 	.dynamic_burst = false,
951 	.has_slavemode = false,
952 	.devtype = IMX21_CSPI,
953 };
954 
955 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
956 	/* i.mx27 cspi shares the functions with i.mx21 one */
957 	.intctrl = mx21_intctrl,
958 	.prepare_message = mx21_prepare_message,
959 	.prepare_transfer = mx21_prepare_transfer,
960 	.trigger = mx21_trigger,
961 	.rx_available = mx21_rx_available,
962 	.reset = mx21_reset,
963 	.fifo_size = 8,
964 	.has_dmamode = false,
965 	.dynamic_burst = false,
966 	.has_slavemode = false,
967 	.devtype = IMX27_CSPI,
968 };
969 
970 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
971 	.intctrl = mx31_intctrl,
972 	.prepare_message = mx31_prepare_message,
973 	.prepare_transfer = mx31_prepare_transfer,
974 	.trigger = mx31_trigger,
975 	.rx_available = mx31_rx_available,
976 	.reset = mx31_reset,
977 	.fifo_size = 8,
978 	.has_dmamode = false,
979 	.dynamic_burst = false,
980 	.has_slavemode = false,
981 	.devtype = IMX31_CSPI,
982 };
983 
984 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
985 	/* i.mx35 and later cspi shares the functions with i.mx31 one */
986 	.intctrl = mx31_intctrl,
987 	.prepare_message = mx31_prepare_message,
988 	.prepare_transfer = mx31_prepare_transfer,
989 	.trigger = mx31_trigger,
990 	.rx_available = mx31_rx_available,
991 	.reset = mx31_reset,
992 	.fifo_size = 8,
993 	.has_dmamode = true,
994 	.dynamic_burst = false,
995 	.has_slavemode = false,
996 	.devtype = IMX35_CSPI,
997 };
998 
999 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
1000 	.intctrl = mx51_ecspi_intctrl,
1001 	.prepare_message = mx51_ecspi_prepare_message,
1002 	.prepare_transfer = mx51_ecspi_prepare_transfer,
1003 	.trigger = mx51_ecspi_trigger,
1004 	.rx_available = mx51_ecspi_rx_available,
1005 	.reset = mx51_ecspi_reset,
1006 	.setup_wml = mx51_setup_wml,
1007 	.disable_dma = mx51_disable_dma,
1008 	.fifo_size = 64,
1009 	.has_dmamode = true,
1010 	.dynamic_burst = true,
1011 	.has_slavemode = true,
1012 	.disable = mx51_ecspi_disable,
1013 	.devtype = IMX51_ECSPI,
1014 };
1015 
1016 static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
1017 	.intctrl = mx51_ecspi_intctrl,
1018 	.prepare_message = mx51_ecspi_prepare_message,
1019 	.prepare_transfer = mx51_ecspi_prepare_transfer,
1020 	.trigger = mx51_ecspi_trigger,
1021 	.rx_available = mx51_ecspi_rx_available,
1022 	.disable_dma = mx51_disable_dma,
1023 	.reset = mx51_ecspi_reset,
1024 	.fifo_size = 64,
1025 	.has_dmamode = true,
1026 	.has_slavemode = true,
1027 	.disable = mx51_ecspi_disable,
1028 	.devtype = IMX53_ECSPI,
1029 };
1030 
1031 static const struct of_device_id spi_imx_dt_ids[] = {
1032 	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
1033 	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
1034 	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
1035 	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
1036 	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
1037 	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
1038 	{ .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
1039 	{ /* sentinel */ }
1040 };
1041 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
1042 
1043 static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
1044 {
1045 	u32 ctrl;
1046 
1047 	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
1048 	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
1049 	ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
1050 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
1051 }
1052 
1053 static void spi_imx_push(struct spi_imx_data *spi_imx)
1054 {
1055 	unsigned int burst_len, fifo_words;
1056 
1057 	if (spi_imx->dynamic_burst)
1058 		fifo_words = 4;
1059 	else
1060 		fifo_words = spi_imx_bytes_per_word(spi_imx->bits_per_word);
1061 	/*
1062 	 * Reload the FIFO when the remaining bytes to be transferred in the
1063 	 * current burst is 0. This only applies when bits_per_word is a
1064 	 * multiple of 8.
1065 	 */
1066 	if (!spi_imx->remainder) {
1067 		if (spi_imx->dynamic_burst) {
1068 
1069 			/* We need to deal unaligned data first */
1070 			burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
1071 
1072 			if (!burst_len)
1073 				burst_len = MX51_ECSPI_CTRL_MAX_BURST;
1074 
1075 			spi_imx_set_burst_len(spi_imx, burst_len * 8);
1076 
1077 			spi_imx->remainder = burst_len;
1078 		} else {
1079 			spi_imx->remainder = fifo_words;
1080 		}
1081 	}
1082 
1083 	while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
1084 		if (!spi_imx->count)
1085 			break;
1086 		if (spi_imx->dynamic_burst &&
1087 		    spi_imx->txfifo >= DIV_ROUND_UP(spi_imx->remainder,
1088 						     fifo_words))
1089 			break;
1090 		spi_imx->tx(spi_imx);
1091 		spi_imx->txfifo++;
1092 	}
1093 
1094 	if (!spi_imx->slave_mode)
1095 		spi_imx->devtype_data->trigger(spi_imx);
1096 }
1097 
1098 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
1099 {
1100 	struct spi_imx_data *spi_imx = dev_id;
1101 
1102 	while (spi_imx->txfifo &&
1103 	       spi_imx->devtype_data->rx_available(spi_imx)) {
1104 		spi_imx->rx(spi_imx);
1105 		spi_imx->txfifo--;
1106 	}
1107 
1108 	if (spi_imx->count) {
1109 		spi_imx_push(spi_imx);
1110 		return IRQ_HANDLED;
1111 	}
1112 
1113 	if (spi_imx->txfifo) {
1114 		/* No data left to push, but still waiting for rx data,
1115 		 * enable receive data available interrupt.
1116 		 */
1117 		spi_imx->devtype_data->intctrl(
1118 				spi_imx, MXC_INT_RR);
1119 		return IRQ_HANDLED;
1120 	}
1121 
1122 	spi_imx->devtype_data->intctrl(spi_imx, 0);
1123 	complete(&spi_imx->xfer_done);
1124 
1125 	return IRQ_HANDLED;
1126 }
1127 
1128 static int spi_imx_dma_configure(struct spi_master *master)
1129 {
1130 	int ret;
1131 	enum dma_slave_buswidth buswidth;
1132 	struct dma_slave_config rx = {}, tx = {};
1133 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1134 
1135 	switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
1136 	case 4:
1137 		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
1138 		break;
1139 	case 2:
1140 		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
1141 		break;
1142 	case 1:
1143 		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
1144 		break;
1145 	default:
1146 		return -EINVAL;
1147 	}
1148 
1149 	tx.direction = DMA_MEM_TO_DEV;
1150 	tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
1151 	tx.dst_addr_width = buswidth;
1152 	tx.dst_maxburst = spi_imx->wml;
1153 	ret = dmaengine_slave_config(master->dma_tx, &tx);
1154 	if (ret) {
1155 		dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
1156 		return ret;
1157 	}
1158 
1159 	rx.direction = DMA_DEV_TO_MEM;
1160 	rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
1161 	rx.src_addr_width = buswidth;
1162 	rx.src_maxburst = spi_imx->wml;
1163 	ret = dmaengine_slave_config(master->dma_rx, &rx);
1164 	if (ret) {
1165 		dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
1166 		return ret;
1167 	}
1168 
1169 	return 0;
1170 }
1171 
1172 static int spi_imx_setupxfer(struct spi_device *spi,
1173 				 struct spi_transfer *t)
1174 {
1175 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1176 
1177 	if (!t)
1178 		return 0;
1179 
1180 	if (!t->speed_hz) {
1181 		if (!spi->max_speed_hz) {
1182 			dev_err(&spi->dev, "no speed_hz provided!\n");
1183 			return -EINVAL;
1184 		}
1185 		dev_dbg(&spi->dev, "using spi->max_speed_hz!\n");
1186 		spi_imx->spi_bus_clk = spi->max_speed_hz;
1187 	} else
1188 		spi_imx->spi_bus_clk = t->speed_hz;
1189 
1190 	spi_imx->bits_per_word = t->bits_per_word;
1191 
1192 	/*
1193 	 * Initialize the functions for transfer. To transfer non byte-aligned
1194 	 * words, we have to use multiple word-size bursts, we can't use
1195 	 * dynamic_burst in that case.
1196 	 */
1197 	if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode &&
1198 	    (spi_imx->bits_per_word == 8 ||
1199 	    spi_imx->bits_per_word == 16 ||
1200 	    spi_imx->bits_per_word == 32)) {
1201 
1202 		spi_imx->rx = spi_imx_buf_rx_swap;
1203 		spi_imx->tx = spi_imx_buf_tx_swap;
1204 		spi_imx->dynamic_burst = 1;
1205 
1206 	} else {
1207 		if (spi_imx->bits_per_word <= 8) {
1208 			spi_imx->rx = spi_imx_buf_rx_u8;
1209 			spi_imx->tx = spi_imx_buf_tx_u8;
1210 		} else if (spi_imx->bits_per_word <= 16) {
1211 			spi_imx->rx = spi_imx_buf_rx_u16;
1212 			spi_imx->tx = spi_imx_buf_tx_u16;
1213 		} else {
1214 			spi_imx->rx = spi_imx_buf_rx_u32;
1215 			spi_imx->tx = spi_imx_buf_tx_u32;
1216 		}
1217 		spi_imx->dynamic_burst = 0;
1218 	}
1219 
1220 	if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
1221 		spi_imx->usedma = true;
1222 	else
1223 		spi_imx->usedma = false;
1224 
1225 	if (is_imx53_ecspi(spi_imx) && spi_imx->slave_mode) {
1226 		spi_imx->rx = mx53_ecspi_rx_slave;
1227 		spi_imx->tx = mx53_ecspi_tx_slave;
1228 		spi_imx->slave_burst = t->len;
1229 	}
1230 
1231 	spi_imx->devtype_data->prepare_transfer(spi_imx, spi);
1232 
1233 	return 0;
1234 }
1235 
1236 static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
1237 {
1238 	struct spi_master *master = spi_imx->bitbang.master;
1239 
1240 	if (master->dma_rx) {
1241 		dma_release_channel(master->dma_rx);
1242 		master->dma_rx = NULL;
1243 	}
1244 
1245 	if (master->dma_tx) {
1246 		dma_release_channel(master->dma_tx);
1247 		master->dma_tx = NULL;
1248 	}
1249 }
1250 
1251 static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
1252 			     struct spi_master *master)
1253 {
1254 	int ret;
1255 
1256 	/* use pio mode for i.mx6dl chip TKT238285 */
1257 	if (of_machine_is_compatible("fsl,imx6dl"))
1258 		return 0;
1259 
1260 	spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
1261 
1262 	/* Prepare for TX DMA: */
1263 	master->dma_tx = dma_request_chan(dev, "tx");
1264 	if (IS_ERR(master->dma_tx)) {
1265 		ret = PTR_ERR(master->dma_tx);
1266 		dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
1267 		master->dma_tx = NULL;
1268 		goto err;
1269 	}
1270 
1271 	/* Prepare for RX : */
1272 	master->dma_rx = dma_request_chan(dev, "rx");
1273 	if (IS_ERR(master->dma_rx)) {
1274 		ret = PTR_ERR(master->dma_rx);
1275 		dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
1276 		master->dma_rx = NULL;
1277 		goto err;
1278 	}
1279 
1280 	init_completion(&spi_imx->dma_rx_completion);
1281 	init_completion(&spi_imx->dma_tx_completion);
1282 	master->can_dma = spi_imx_can_dma;
1283 	master->max_dma_len = MAX_SDMA_BD_BYTES;
1284 	spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
1285 					 SPI_MASTER_MUST_TX;
1286 
1287 	return 0;
1288 err:
1289 	spi_imx_sdma_exit(spi_imx);
1290 	return ret;
1291 }
1292 
1293 static void spi_imx_dma_rx_callback(void *cookie)
1294 {
1295 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1296 
1297 	complete(&spi_imx->dma_rx_completion);
1298 }
1299 
1300 static void spi_imx_dma_tx_callback(void *cookie)
1301 {
1302 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1303 
1304 	complete(&spi_imx->dma_tx_completion);
1305 }
1306 
1307 static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1308 {
1309 	unsigned long timeout = 0;
1310 
1311 	/* Time with actual data transfer and CS change delay related to HW */
1312 	timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1313 
1314 	/* Add extra second for scheduler related activities */
1315 	timeout += 1;
1316 
1317 	/* Double calculated timeout */
1318 	return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1319 }
1320 
1321 static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1322 				struct spi_transfer *transfer)
1323 {
1324 	struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1325 	unsigned long transfer_timeout;
1326 	unsigned long timeout;
1327 	struct spi_master *master = spi_imx->bitbang.master;
1328 	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1329 	struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
1330 	unsigned int bytes_per_word, i;
1331 	int ret;
1332 
1333 	/* Get the right burst length from the last sg to ensure no tail data */
1334 	bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
1335 	for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
1336 		if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
1337 			break;
1338 	}
1339 	/* Use 1 as wml in case no available burst length got */
1340 	if (i == 0)
1341 		i = 1;
1342 
1343 	spi_imx->wml =  i;
1344 
1345 	ret = spi_imx_dma_configure(master);
1346 	if (ret)
1347 		goto dma_failure_no_start;
1348 
1349 	if (!spi_imx->devtype_data->setup_wml) {
1350 		dev_err(spi_imx->dev, "No setup_wml()?\n");
1351 		ret = -EINVAL;
1352 		goto dma_failure_no_start;
1353 	}
1354 	spi_imx->devtype_data->setup_wml(spi_imx);
1355 
1356 	/*
1357 	 * The TX DMA setup starts the transfer, so make sure RX is configured
1358 	 * before TX.
1359 	 */
1360 	desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
1361 				rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1362 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1363 	if (!desc_rx) {
1364 		ret = -EINVAL;
1365 		goto dma_failure_no_start;
1366 	}
1367 
1368 	desc_rx->callback = spi_imx_dma_rx_callback;
1369 	desc_rx->callback_param = (void *)spi_imx;
1370 	dmaengine_submit(desc_rx);
1371 	reinit_completion(&spi_imx->dma_rx_completion);
1372 	dma_async_issue_pending(master->dma_rx);
1373 
1374 	desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
1375 				tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1376 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1377 	if (!desc_tx) {
1378 		dmaengine_terminate_all(master->dma_tx);
1379 		dmaengine_terminate_all(master->dma_rx);
1380 		return -EINVAL;
1381 	}
1382 
1383 	desc_tx->callback = spi_imx_dma_tx_callback;
1384 	desc_tx->callback_param = (void *)spi_imx;
1385 	dmaengine_submit(desc_tx);
1386 	reinit_completion(&spi_imx->dma_tx_completion);
1387 	dma_async_issue_pending(master->dma_tx);
1388 
1389 	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1390 
1391 	/* Wait SDMA to finish the data transfer.*/
1392 	timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1393 						transfer_timeout);
1394 	if (!timeout) {
1395 		dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1396 		dmaengine_terminate_all(master->dma_tx);
1397 		dmaengine_terminate_all(master->dma_rx);
1398 		return -ETIMEDOUT;
1399 	}
1400 
1401 	timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1402 					      transfer_timeout);
1403 	if (!timeout) {
1404 		dev_err(&master->dev, "I/O Error in DMA RX\n");
1405 		spi_imx->devtype_data->reset(spi_imx);
1406 		dmaengine_terminate_all(master->dma_rx);
1407 		return -ETIMEDOUT;
1408 	}
1409 
1410 	return transfer->len;
1411 /* fallback to pio */
1412 dma_failure_no_start:
1413 	transfer->error |= SPI_TRANS_FAIL_NO_START;
1414 	return ret;
1415 }
1416 
1417 static int spi_imx_pio_transfer(struct spi_device *spi,
1418 				struct spi_transfer *transfer)
1419 {
1420 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1421 	unsigned long transfer_timeout;
1422 	unsigned long timeout;
1423 
1424 	spi_imx->tx_buf = transfer->tx_buf;
1425 	spi_imx->rx_buf = transfer->rx_buf;
1426 	spi_imx->count = transfer->len;
1427 	spi_imx->txfifo = 0;
1428 	spi_imx->remainder = 0;
1429 
1430 	reinit_completion(&spi_imx->xfer_done);
1431 
1432 	spi_imx_push(spi_imx);
1433 
1434 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1435 
1436 	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1437 
1438 	timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
1439 					      transfer_timeout);
1440 	if (!timeout) {
1441 		dev_err(&spi->dev, "I/O Error in PIO\n");
1442 		spi_imx->devtype_data->reset(spi_imx);
1443 		return -ETIMEDOUT;
1444 	}
1445 
1446 	return transfer->len;
1447 }
1448 
1449 static int spi_imx_pio_transfer_slave(struct spi_device *spi,
1450 				      struct spi_transfer *transfer)
1451 {
1452 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1453 	int ret = transfer->len;
1454 
1455 	if (is_imx53_ecspi(spi_imx) &&
1456 	    transfer->len > MX53_MAX_TRANSFER_BYTES) {
1457 		dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
1458 			MX53_MAX_TRANSFER_BYTES);
1459 		return -EMSGSIZE;
1460 	}
1461 
1462 	spi_imx->tx_buf = transfer->tx_buf;
1463 	spi_imx->rx_buf = transfer->rx_buf;
1464 	spi_imx->count = transfer->len;
1465 	spi_imx->txfifo = 0;
1466 	spi_imx->remainder = 0;
1467 
1468 	reinit_completion(&spi_imx->xfer_done);
1469 	spi_imx->slave_aborted = false;
1470 
1471 	spi_imx_push(spi_imx);
1472 
1473 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
1474 
1475 	if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
1476 	    spi_imx->slave_aborted) {
1477 		dev_dbg(&spi->dev, "interrupted\n");
1478 		ret = -EINTR;
1479 	}
1480 
1481 	/* ecspi has a HW issue when works in Slave mode,
1482 	 * after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
1483 	 * ECSPI_TXDATA keeps shift out the last word data,
1484 	 * so we have to disable ECSPI when in slave mode after the
1485 	 * transfer completes
1486 	 */
1487 	if (spi_imx->devtype_data->disable)
1488 		spi_imx->devtype_data->disable(spi_imx);
1489 
1490 	return ret;
1491 }
1492 
1493 static int spi_imx_transfer(struct spi_device *spi,
1494 				struct spi_transfer *transfer)
1495 {
1496 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1497 
1498 	transfer->effective_speed_hz = spi_imx->spi_bus_clk;
1499 
1500 	/* flush rxfifo before transfer */
1501 	while (spi_imx->devtype_data->rx_available(spi_imx))
1502 		readl(spi_imx->base + MXC_CSPIRXDATA);
1503 
1504 	if (spi_imx->slave_mode)
1505 		return spi_imx_pio_transfer_slave(spi, transfer);
1506 
1507 	if (spi_imx->usedma)
1508 		return spi_imx_dma_transfer(spi_imx, transfer);
1509 
1510 	return spi_imx_pio_transfer(spi, transfer);
1511 }
1512 
1513 static int spi_imx_setup(struct spi_device *spi)
1514 {
1515 	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1516 		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1517 
1518 	return 0;
1519 }
1520 
1521 static void spi_imx_cleanup(struct spi_device *spi)
1522 {
1523 }
1524 
1525 static int
1526 spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1527 {
1528 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1529 	int ret;
1530 
1531 	ret = pm_runtime_get_sync(spi_imx->dev);
1532 	if (ret < 0) {
1533 		pm_runtime_put_noidle(spi_imx->dev);
1534 		dev_err(spi_imx->dev, "failed to enable clock\n");
1535 		return ret;
1536 	}
1537 
1538 	ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
1539 	if (ret) {
1540 		pm_runtime_mark_last_busy(spi_imx->dev);
1541 		pm_runtime_put_autosuspend(spi_imx->dev);
1542 	}
1543 
1544 	return ret;
1545 }
1546 
1547 static int
1548 spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1549 {
1550 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1551 
1552 	pm_runtime_mark_last_busy(spi_imx->dev);
1553 	pm_runtime_put_autosuspend(spi_imx->dev);
1554 	return 0;
1555 }
1556 
1557 static int spi_imx_slave_abort(struct spi_master *master)
1558 {
1559 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1560 
1561 	spi_imx->slave_aborted = true;
1562 	complete(&spi_imx->xfer_done);
1563 
1564 	return 0;
1565 }
1566 
1567 static int spi_imx_probe(struct platform_device *pdev)
1568 {
1569 	struct device_node *np = pdev->dev.of_node;
1570 	struct spi_master *master;
1571 	struct spi_imx_data *spi_imx;
1572 	struct resource *res;
1573 	int ret, irq, spi_drctl;
1574 	const struct spi_imx_devtype_data *devtype_data =
1575 			of_device_get_match_data(&pdev->dev);
1576 	bool slave_mode;
1577 	u32 val;
1578 
1579 	slave_mode = devtype_data->has_slavemode &&
1580 			of_property_read_bool(np, "spi-slave");
1581 	if (slave_mode)
1582 		master = spi_alloc_slave(&pdev->dev,
1583 					 sizeof(struct spi_imx_data));
1584 	else
1585 		master = spi_alloc_master(&pdev->dev,
1586 					  sizeof(struct spi_imx_data));
1587 	if (!master)
1588 		return -ENOMEM;
1589 
1590 	ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
1591 	if ((ret < 0) || (spi_drctl >= 0x3)) {
1592 		/* '11' is reserved */
1593 		spi_drctl = 0;
1594 	}
1595 
1596 	platform_set_drvdata(pdev, master);
1597 
1598 	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1599 	master->bus_num = np ? -1 : pdev->id;
1600 	master->use_gpio_descriptors = true;
1601 
1602 	spi_imx = spi_master_get_devdata(master);
1603 	spi_imx->bitbang.master = master;
1604 	spi_imx->dev = &pdev->dev;
1605 	spi_imx->slave_mode = slave_mode;
1606 
1607 	spi_imx->devtype_data = devtype_data;
1608 
1609 	/*
1610 	 * Get number of chip selects from device properties. This can be
1611 	 * coming from device tree or boardfiles, if it is not defined,
1612 	 * a default value of 3 chip selects will be used, as all the legacy
1613 	 * board files have <= 3 chip selects.
1614 	 */
1615 	if (!device_property_read_u32(&pdev->dev, "num-cs", &val))
1616 		master->num_chipselect = val;
1617 	else
1618 		master->num_chipselect = 3;
1619 
1620 	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1621 	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1622 	spi_imx->bitbang.master->setup = spi_imx_setup;
1623 	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1624 	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1625 	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1626 	spi_imx->bitbang.master->slave_abort = spi_imx_slave_abort;
1627 	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
1628 					     | SPI_NO_CS;
1629 	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
1630 	    is_imx53_ecspi(spi_imx))
1631 		spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY;
1632 
1633 	spi_imx->spi_drctl = spi_drctl;
1634 
1635 	init_completion(&spi_imx->xfer_done);
1636 
1637 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1638 	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1639 	if (IS_ERR(spi_imx->base)) {
1640 		ret = PTR_ERR(spi_imx->base);
1641 		goto out_master_put;
1642 	}
1643 	spi_imx->base_phys = res->start;
1644 
1645 	irq = platform_get_irq(pdev, 0);
1646 	if (irq < 0) {
1647 		ret = irq;
1648 		goto out_master_put;
1649 	}
1650 
1651 	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1652 			       dev_name(&pdev->dev), spi_imx);
1653 	if (ret) {
1654 		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1655 		goto out_master_put;
1656 	}
1657 
1658 	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1659 	if (IS_ERR(spi_imx->clk_ipg)) {
1660 		ret = PTR_ERR(spi_imx->clk_ipg);
1661 		goto out_master_put;
1662 	}
1663 
1664 	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1665 	if (IS_ERR(spi_imx->clk_per)) {
1666 		ret = PTR_ERR(spi_imx->clk_per);
1667 		goto out_master_put;
1668 	}
1669 
1670 	ret = clk_prepare_enable(spi_imx->clk_per);
1671 	if (ret)
1672 		goto out_master_put;
1673 
1674 	ret = clk_prepare_enable(spi_imx->clk_ipg);
1675 	if (ret)
1676 		goto out_put_per;
1677 
1678 	pm_runtime_set_autosuspend_delay(spi_imx->dev, MXC_RPM_TIMEOUT);
1679 	pm_runtime_use_autosuspend(spi_imx->dev);
1680 	pm_runtime_get_noresume(spi_imx->dev);
1681 	pm_runtime_set_active(spi_imx->dev);
1682 	pm_runtime_enable(spi_imx->dev);
1683 
1684 	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1685 	/*
1686 	 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1687 	 * if validated on other chips.
1688 	 */
1689 	if (spi_imx->devtype_data->has_dmamode) {
1690 		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
1691 		if (ret == -EPROBE_DEFER)
1692 			goto out_runtime_pm_put;
1693 
1694 		if (ret < 0)
1695 			dev_dbg(&pdev->dev, "dma setup error %d, use pio\n",
1696 				ret);
1697 	}
1698 
1699 	spi_imx->devtype_data->reset(spi_imx);
1700 
1701 	spi_imx->devtype_data->intctrl(spi_imx, 0);
1702 
1703 	master->dev.of_node = pdev->dev.of_node;
1704 	ret = spi_bitbang_start(&spi_imx->bitbang);
1705 	if (ret) {
1706 		dev_err_probe(&pdev->dev, ret, "bitbang start failed\n");
1707 		goto out_bitbang_start;
1708 	}
1709 
1710 	pm_runtime_mark_last_busy(spi_imx->dev);
1711 	pm_runtime_put_autosuspend(spi_imx->dev);
1712 
1713 	return ret;
1714 
1715 out_bitbang_start:
1716 	if (spi_imx->devtype_data->has_dmamode)
1717 		spi_imx_sdma_exit(spi_imx);
1718 out_runtime_pm_put:
1719 	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1720 	pm_runtime_set_suspended(&pdev->dev);
1721 	pm_runtime_disable(spi_imx->dev);
1722 
1723 	clk_disable_unprepare(spi_imx->clk_ipg);
1724 out_put_per:
1725 	clk_disable_unprepare(spi_imx->clk_per);
1726 out_master_put:
1727 	spi_master_put(master);
1728 
1729 	return ret;
1730 }
1731 
1732 static int spi_imx_remove(struct platform_device *pdev)
1733 {
1734 	struct spi_master *master = platform_get_drvdata(pdev);
1735 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1736 	int ret;
1737 
1738 	spi_bitbang_stop(&spi_imx->bitbang);
1739 
1740 	ret = pm_runtime_get_sync(spi_imx->dev);
1741 	if (ret < 0) {
1742 		pm_runtime_put_noidle(spi_imx->dev);
1743 		dev_err(spi_imx->dev, "failed to enable clock\n");
1744 		return ret;
1745 	}
1746 
1747 	writel(0, spi_imx->base + MXC_CSPICTRL);
1748 
1749 	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1750 	pm_runtime_put_sync(spi_imx->dev);
1751 	pm_runtime_disable(spi_imx->dev);
1752 
1753 	spi_imx_sdma_exit(spi_imx);
1754 	spi_master_put(master);
1755 
1756 	return 0;
1757 }
1758 
1759 static int __maybe_unused spi_imx_runtime_resume(struct device *dev)
1760 {
1761 	struct spi_master *master = dev_get_drvdata(dev);
1762 	struct spi_imx_data *spi_imx;
1763 	int ret;
1764 
1765 	spi_imx = spi_master_get_devdata(master);
1766 
1767 	ret = clk_prepare_enable(spi_imx->clk_per);
1768 	if (ret)
1769 		return ret;
1770 
1771 	ret = clk_prepare_enable(spi_imx->clk_ipg);
1772 	if (ret) {
1773 		clk_disable_unprepare(spi_imx->clk_per);
1774 		return ret;
1775 	}
1776 
1777 	return 0;
1778 }
1779 
1780 static int __maybe_unused spi_imx_runtime_suspend(struct device *dev)
1781 {
1782 	struct spi_master *master = dev_get_drvdata(dev);
1783 	struct spi_imx_data *spi_imx;
1784 
1785 	spi_imx = spi_master_get_devdata(master);
1786 
1787 	clk_disable_unprepare(spi_imx->clk_per);
1788 	clk_disable_unprepare(spi_imx->clk_ipg);
1789 
1790 	return 0;
1791 }
1792 
1793 static int __maybe_unused spi_imx_suspend(struct device *dev)
1794 {
1795 	pinctrl_pm_select_sleep_state(dev);
1796 	return 0;
1797 }
1798 
1799 static int __maybe_unused spi_imx_resume(struct device *dev)
1800 {
1801 	pinctrl_pm_select_default_state(dev);
1802 	return 0;
1803 }
1804 
1805 static const struct dev_pm_ops imx_spi_pm = {
1806 	SET_RUNTIME_PM_OPS(spi_imx_runtime_suspend,
1807 				spi_imx_runtime_resume, NULL)
1808 	SET_SYSTEM_SLEEP_PM_OPS(spi_imx_suspend, spi_imx_resume)
1809 };
1810 
1811 static struct platform_driver spi_imx_driver = {
1812 	.driver = {
1813 		   .name = DRIVER_NAME,
1814 		   .of_match_table = spi_imx_dt_ids,
1815 		   .pm = &imx_spi_pm,
1816 	},
1817 	.probe = spi_imx_probe,
1818 	.remove = spi_imx_remove,
1819 };
1820 module_platform_driver(spi_imx_driver);
1821 
1822 MODULE_DESCRIPTION("i.MX SPI Controller driver");
1823 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1824 MODULE_LICENSE("GPL");
1825 MODULE_ALIAS("platform:" DRIVER_NAME);
1826