xref: /linux/drivers/spi/spi-imx.c (revision 4ac6d90867a4de2e12117e755dbd76e08d88697f)
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 	/*
81 	 * ERR009165 fixed or not:
82 	 * https://www.nxp.com/docs/en/errata/IMX6DQCE.pdf
83 	 */
84 	bool tx_glitch_fixed;
85 	enum spi_imx_devtype devtype;
86 };
87 
88 struct spi_imx_data {
89 	struct spi_bitbang bitbang;
90 	struct device *dev;
91 
92 	struct completion xfer_done;
93 	void __iomem *base;
94 	unsigned long base_phys;
95 
96 	struct clk *clk_per;
97 	struct clk *clk_ipg;
98 	unsigned long spi_clk;
99 	unsigned int spi_bus_clk;
100 
101 	unsigned int bits_per_word;
102 	unsigned int spi_drctl;
103 
104 	unsigned int count, remainder;
105 	void (*tx)(struct spi_imx_data *);
106 	void (*rx)(struct spi_imx_data *);
107 	void *rx_buf;
108 	const void *tx_buf;
109 	unsigned int txfifo; /* number of words pushed in tx FIFO */
110 	unsigned int dynamic_burst;
111 
112 	/* Slave mode */
113 	bool slave_mode;
114 	bool slave_aborted;
115 	unsigned int slave_burst;
116 
117 	/* DMA */
118 	bool usedma;
119 	u32 wml;
120 	struct completion dma_rx_completion;
121 	struct completion dma_tx_completion;
122 
123 	const struct spi_imx_devtype_data *devtype_data;
124 };
125 
126 static inline int is_imx27_cspi(struct spi_imx_data *d)
127 {
128 	return d->devtype_data->devtype == IMX27_CSPI;
129 }
130 
131 static inline int is_imx35_cspi(struct spi_imx_data *d)
132 {
133 	return d->devtype_data->devtype == IMX35_CSPI;
134 }
135 
136 static inline int is_imx51_ecspi(struct spi_imx_data *d)
137 {
138 	return d->devtype_data->devtype == IMX51_ECSPI;
139 }
140 
141 static inline int is_imx53_ecspi(struct spi_imx_data *d)
142 {
143 	return d->devtype_data->devtype == IMX53_ECSPI;
144 }
145 
146 #define MXC_SPI_BUF_RX(type)						\
147 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
148 {									\
149 	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
150 									\
151 	if (spi_imx->rx_buf) {						\
152 		*(type *)spi_imx->rx_buf = val;				\
153 		spi_imx->rx_buf += sizeof(type);			\
154 	}								\
155 									\
156 	spi_imx->remainder -= sizeof(type);				\
157 }
158 
159 #define MXC_SPI_BUF_TX(type)						\
160 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
161 {									\
162 	type val = 0;							\
163 									\
164 	if (spi_imx->tx_buf) {						\
165 		val = *(type *)spi_imx->tx_buf;				\
166 		spi_imx->tx_buf += sizeof(type);			\
167 	}								\
168 									\
169 	spi_imx->count -= sizeof(type);					\
170 									\
171 	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
172 }
173 
174 MXC_SPI_BUF_RX(u8)
175 MXC_SPI_BUF_TX(u8)
176 MXC_SPI_BUF_RX(u16)
177 MXC_SPI_BUF_TX(u16)
178 MXC_SPI_BUF_RX(u32)
179 MXC_SPI_BUF_TX(u32)
180 
181 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
182  * (which is currently not the case in this driver)
183  */
184 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
185 	256, 384, 512, 768, 1024};
186 
187 /* MX21, MX27 */
188 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
189 		unsigned int fspi, unsigned int max, unsigned int *fres)
190 {
191 	int i;
192 
193 	for (i = 2; i < max; i++)
194 		if (fspi * mxc_clkdivs[i] >= fin)
195 			break;
196 
197 	*fres = fin / mxc_clkdivs[i];
198 	return i;
199 }
200 
201 /* MX1, MX31, MX35, MX51 CSPI */
202 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
203 		unsigned int fspi, unsigned int *fres)
204 {
205 	int i, div = 4;
206 
207 	for (i = 0; i < 7; i++) {
208 		if (fspi * div >= fin)
209 			goto out;
210 		div <<= 1;
211 	}
212 
213 out:
214 	*fres = fin / div;
215 	return i;
216 }
217 
218 static int spi_imx_bytes_per_word(const int bits_per_word)
219 {
220 	if (bits_per_word <= 8)
221 		return 1;
222 	else if (bits_per_word <= 16)
223 		return 2;
224 	else
225 		return 4;
226 }
227 
228 static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
229 			 struct spi_transfer *transfer)
230 {
231 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
232 
233 	if (!use_dma || master->fallback)
234 		return false;
235 
236 	if (!master->dma_rx)
237 		return false;
238 
239 	if (spi_imx->slave_mode)
240 		return false;
241 
242 	if (transfer->len < spi_imx->devtype_data->fifo_size)
243 		return false;
244 
245 	spi_imx->dynamic_burst = 0;
246 
247 	return true;
248 }
249 
250 #define MX51_ECSPI_CTRL		0x08
251 #define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
252 #define MX51_ECSPI_CTRL_XCH		(1 <<  2)
253 #define MX51_ECSPI_CTRL_SMC		(1 << 3)
254 #define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
255 #define MX51_ECSPI_CTRL_DRCTL(drctl)	((drctl) << 16)
256 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
257 #define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
258 #define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
259 #define MX51_ECSPI_CTRL_BL_OFFSET	20
260 #define MX51_ECSPI_CTRL_BL_MASK		(0xfff << 20)
261 
262 #define MX51_ECSPI_CONFIG	0x0c
263 #define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
264 #define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
265 #define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
266 #define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
267 #define MX51_ECSPI_CONFIG_SCLKCTL(cs)	(1 << ((cs) + 20))
268 
269 #define MX51_ECSPI_INT		0x10
270 #define MX51_ECSPI_INT_TEEN		(1 <<  0)
271 #define MX51_ECSPI_INT_RREN		(1 <<  3)
272 #define MX51_ECSPI_INT_RDREN		(1 <<  4)
273 
274 #define MX51_ECSPI_DMA		0x14
275 #define MX51_ECSPI_DMA_TX_WML(wml)	((wml) & 0x3f)
276 #define MX51_ECSPI_DMA_RX_WML(wml)	(((wml) & 0x3f) << 16)
277 #define MX51_ECSPI_DMA_RXT_WML(wml)	(((wml) & 0x3f) << 24)
278 
279 #define MX51_ECSPI_DMA_TEDEN		(1 << 7)
280 #define MX51_ECSPI_DMA_RXDEN		(1 << 23)
281 #define MX51_ECSPI_DMA_RXTDEN		(1 << 31)
282 
283 #define MX51_ECSPI_STAT		0x18
284 #define MX51_ECSPI_STAT_RR		(1 <<  3)
285 
286 #define MX51_ECSPI_TESTREG	0x20
287 #define MX51_ECSPI_TESTREG_LBC	BIT(31)
288 
289 static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
290 {
291 	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
292 #ifdef __LITTLE_ENDIAN
293 	unsigned int bytes_per_word;
294 #endif
295 
296 	if (spi_imx->rx_buf) {
297 #ifdef __LITTLE_ENDIAN
298 		bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
299 		if (bytes_per_word == 1)
300 			val = cpu_to_be32(val);
301 		else if (bytes_per_word == 2)
302 			val = (val << 16) | (val >> 16);
303 #endif
304 		*(u32 *)spi_imx->rx_buf = val;
305 		spi_imx->rx_buf += sizeof(u32);
306 	}
307 
308 	spi_imx->remainder -= sizeof(u32);
309 }
310 
311 static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
312 {
313 	int unaligned;
314 	u32 val;
315 
316 	unaligned = spi_imx->remainder % 4;
317 
318 	if (!unaligned) {
319 		spi_imx_buf_rx_swap_u32(spi_imx);
320 		return;
321 	}
322 
323 	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
324 		spi_imx_buf_rx_u16(spi_imx);
325 		return;
326 	}
327 
328 	val = readl(spi_imx->base + MXC_CSPIRXDATA);
329 
330 	while (unaligned--) {
331 		if (spi_imx->rx_buf) {
332 			*(u8 *)spi_imx->rx_buf = (val >> (8 * unaligned)) & 0xff;
333 			spi_imx->rx_buf++;
334 		}
335 		spi_imx->remainder--;
336 	}
337 }
338 
339 static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
340 {
341 	u32 val = 0;
342 #ifdef __LITTLE_ENDIAN
343 	unsigned int bytes_per_word;
344 #endif
345 
346 	if (spi_imx->tx_buf) {
347 		val = *(u32 *)spi_imx->tx_buf;
348 		spi_imx->tx_buf += sizeof(u32);
349 	}
350 
351 	spi_imx->count -= sizeof(u32);
352 #ifdef __LITTLE_ENDIAN
353 	bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
354 
355 	if (bytes_per_word == 1)
356 		val = cpu_to_be32(val);
357 	else if (bytes_per_word == 2)
358 		val = (val << 16) | (val >> 16);
359 #endif
360 	writel(val, spi_imx->base + MXC_CSPITXDATA);
361 }
362 
363 static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
364 {
365 	int unaligned;
366 	u32 val = 0;
367 
368 	unaligned = spi_imx->count % 4;
369 
370 	if (!unaligned) {
371 		spi_imx_buf_tx_swap_u32(spi_imx);
372 		return;
373 	}
374 
375 	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
376 		spi_imx_buf_tx_u16(spi_imx);
377 		return;
378 	}
379 
380 	while (unaligned--) {
381 		if (spi_imx->tx_buf) {
382 			val |= *(u8 *)spi_imx->tx_buf << (8 * unaligned);
383 			spi_imx->tx_buf++;
384 		}
385 		spi_imx->count--;
386 	}
387 
388 	writel(val, spi_imx->base + MXC_CSPITXDATA);
389 }
390 
391 static void mx53_ecspi_rx_slave(struct spi_imx_data *spi_imx)
392 {
393 	u32 val = be32_to_cpu(readl(spi_imx->base + MXC_CSPIRXDATA));
394 
395 	if (spi_imx->rx_buf) {
396 		int n_bytes = spi_imx->slave_burst % sizeof(val);
397 
398 		if (!n_bytes)
399 			n_bytes = sizeof(val);
400 
401 		memcpy(spi_imx->rx_buf,
402 		       ((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
403 
404 		spi_imx->rx_buf += n_bytes;
405 		spi_imx->slave_burst -= n_bytes;
406 	}
407 
408 	spi_imx->remainder -= sizeof(u32);
409 }
410 
411 static void mx53_ecspi_tx_slave(struct spi_imx_data *spi_imx)
412 {
413 	u32 val = 0;
414 	int n_bytes = spi_imx->count % sizeof(val);
415 
416 	if (!n_bytes)
417 		n_bytes = sizeof(val);
418 
419 	if (spi_imx->tx_buf) {
420 		memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
421 		       spi_imx->tx_buf, n_bytes);
422 		val = cpu_to_be32(val);
423 		spi_imx->tx_buf += n_bytes;
424 	}
425 
426 	spi_imx->count -= n_bytes;
427 
428 	writel(val, spi_imx->base + MXC_CSPITXDATA);
429 }
430 
431 /* MX51 eCSPI */
432 static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
433 				      unsigned int fspi, unsigned int *fres)
434 {
435 	/*
436 	 * there are two 4-bit dividers, the pre-divider divides by
437 	 * $pre, the post-divider by 2^$post
438 	 */
439 	unsigned int pre, post;
440 	unsigned int fin = spi_imx->spi_clk;
441 
442 	if (unlikely(fspi > fin))
443 		return 0;
444 
445 	post = fls(fin) - fls(fspi);
446 	if (fin > fspi << post)
447 		post++;
448 
449 	/* now we have: (fin <= fspi << post) with post being minimal */
450 
451 	post = max(4U, post) - 4;
452 	if (unlikely(post > 0xf)) {
453 		dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
454 				fspi, fin);
455 		return 0xff;
456 	}
457 
458 	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
459 
460 	dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
461 			__func__, fin, fspi, post, pre);
462 
463 	/* Resulting frequency for the SCLK line. */
464 	*fres = (fin / (pre + 1)) >> post;
465 
466 	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
467 		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
468 }
469 
470 static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
471 {
472 	unsigned val = 0;
473 
474 	if (enable & MXC_INT_TE)
475 		val |= MX51_ECSPI_INT_TEEN;
476 
477 	if (enable & MXC_INT_RR)
478 		val |= MX51_ECSPI_INT_RREN;
479 
480 	if (enable & MXC_INT_RDR)
481 		val |= MX51_ECSPI_INT_RDREN;
482 
483 	writel(val, spi_imx->base + MX51_ECSPI_INT);
484 }
485 
486 static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
487 {
488 	u32 reg;
489 
490 	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
491 	reg |= MX51_ECSPI_CTRL_XCH;
492 	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
493 }
494 
495 static void mx51_disable_dma(struct spi_imx_data *spi_imx)
496 {
497 	writel(0, spi_imx->base + MX51_ECSPI_DMA);
498 }
499 
500 static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
501 {
502 	u32 ctrl;
503 
504 	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
505 	ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
506 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
507 }
508 
509 static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
510 				      struct spi_message *msg)
511 {
512 	struct spi_device *spi = msg->spi;
513 	struct spi_transfer *xfer;
514 	u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
515 	u32 min_speed_hz = ~0U;
516 	u32 testreg, delay;
517 	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
518 
519 	/* set Master or Slave mode */
520 	if (spi_imx->slave_mode)
521 		ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
522 	else
523 		ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
524 
525 	/*
526 	 * Enable SPI_RDY handling (falling edge/level triggered).
527 	 */
528 	if (spi->mode & SPI_READY)
529 		ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
530 
531 	/* set chip select to use */
532 	ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
533 
534 	/*
535 	 * The ctrl register must be written first, with the EN bit set other
536 	 * registers must not be written to.
537 	 */
538 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
539 
540 	testreg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
541 	if (spi->mode & SPI_LOOP)
542 		testreg |= MX51_ECSPI_TESTREG_LBC;
543 	else
544 		testreg &= ~MX51_ECSPI_TESTREG_LBC;
545 	writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
546 
547 	/*
548 	 * eCSPI burst completion by Chip Select signal in Slave mode
549 	 * is not functional for imx53 Soc, config SPI burst completed when
550 	 * BURST_LENGTH + 1 bits are received
551 	 */
552 	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
553 		cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
554 	else
555 		cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
556 
557 	if (spi->mode & SPI_CPHA)
558 		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
559 	else
560 		cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
561 
562 	if (spi->mode & SPI_CPOL) {
563 		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
564 		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
565 	} else {
566 		cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
567 		cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
568 	}
569 
570 	if (spi->mode & SPI_CS_HIGH)
571 		cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
572 	else
573 		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
574 
575 	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
576 
577 	/*
578 	 * Wait until the changes in the configuration register CONFIGREG
579 	 * propagate into the hardware. It takes exactly one tick of the
580 	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
581 	 * effect of the delay it takes for the hardware to apply changes
582 	 * is noticable if the SCLK clock run very slow. In such a case, if
583 	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
584 	 * be asserted before the SCLK polarity changes, which would disrupt
585 	 * the SPI communication as the device on the other end would consider
586 	 * the change of SCLK polarity as a clock tick already.
587 	 *
588 	 * Because spi_imx->spi_bus_clk is only set in bitbang prepare_message
589 	 * callback, iterate over all the transfers in spi_message, find the
590 	 * one with lowest bus frequency, and use that bus frequency for the
591 	 * delay calculation. In case all transfers have speed_hz == 0, then
592 	 * min_speed_hz is ~0 and the resulting delay is zero.
593 	 */
594 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
595 		if (!xfer->speed_hz)
596 			continue;
597 		min_speed_hz = min(xfer->speed_hz, min_speed_hz);
598 	}
599 
600 	delay = (2 * 1000000) / min_speed_hz;
601 	if (likely(delay < 10))	/* SCLK is faster than 200 kHz */
602 		udelay(delay);
603 	else			/* SCLK is _very_ slow */
604 		usleep_range(delay, delay + 10);
605 
606 	return 0;
607 }
608 
609 static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
610 				       struct spi_device *spi)
611 {
612 	u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
613 	u32 clk;
614 
615 	/* Clear BL field and set the right value */
616 	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
617 	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
618 		ctrl |= (spi_imx->slave_burst * 8 - 1)
619 			<< MX51_ECSPI_CTRL_BL_OFFSET;
620 	else
621 		ctrl |= (spi_imx->bits_per_word - 1)
622 			<< MX51_ECSPI_CTRL_BL_OFFSET;
623 
624 	/* set clock speed */
625 	ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
626 		  0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
627 	ctrl |= mx51_ecspi_clkdiv(spi_imx, spi_imx->spi_bus_clk, &clk);
628 	spi_imx->spi_bus_clk = clk;
629 
630 	/*
631 	 * ERR009165: work in XHC mode instead of SMC as PIO on the chips
632 	 * before i.mx6ul.
633 	 */
634 	if (spi_imx->usedma && spi_imx->devtype_data->tx_glitch_fixed)
635 		ctrl |= MX51_ECSPI_CTRL_SMC;
636 	else
637 		ctrl &= ~MX51_ECSPI_CTRL_SMC;
638 
639 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
640 
641 	return 0;
642 }
643 
644 static void mx51_setup_wml(struct spi_imx_data *spi_imx)
645 {
646 	u32 tx_wml = 0;
647 
648 	if (spi_imx->devtype_data->tx_glitch_fixed)
649 		tx_wml = spi_imx->wml;
650 	/*
651 	 * Configure the DMA register: setup the watermark
652 	 * and enable DMA request.
653 	 */
654 	writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) |
655 		MX51_ECSPI_DMA_TX_WML(tx_wml) |
656 		MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
657 		MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
658 		MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
659 }
660 
661 static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
662 {
663 	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
664 }
665 
666 static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
667 {
668 	/* drain receive buffer */
669 	while (mx51_ecspi_rx_available(spi_imx))
670 		readl(spi_imx->base + MXC_CSPIRXDATA);
671 }
672 
673 #define MX31_INTREG_TEEN	(1 << 0)
674 #define MX31_INTREG_RREN	(1 << 3)
675 
676 #define MX31_CSPICTRL_ENABLE	(1 << 0)
677 #define MX31_CSPICTRL_MASTER	(1 << 1)
678 #define MX31_CSPICTRL_XCH	(1 << 2)
679 #define MX31_CSPICTRL_SMC	(1 << 3)
680 #define MX31_CSPICTRL_POL	(1 << 4)
681 #define MX31_CSPICTRL_PHA	(1 << 5)
682 #define MX31_CSPICTRL_SSCTL	(1 << 6)
683 #define MX31_CSPICTRL_SSPOL	(1 << 7)
684 #define MX31_CSPICTRL_BC_SHIFT	8
685 #define MX35_CSPICTRL_BL_SHIFT	20
686 #define MX31_CSPICTRL_CS_SHIFT	24
687 #define MX35_CSPICTRL_CS_SHIFT	12
688 #define MX31_CSPICTRL_DR_SHIFT	16
689 
690 #define MX31_CSPI_DMAREG	0x10
691 #define MX31_DMAREG_RH_DEN	(1<<4)
692 #define MX31_DMAREG_TH_DEN	(1<<1)
693 
694 #define MX31_CSPISTATUS		0x14
695 #define MX31_STATUS_RR		(1 << 3)
696 
697 #define MX31_CSPI_TESTREG	0x1C
698 #define MX31_TEST_LBC		(1 << 14)
699 
700 /* These functions also work for the i.MX35, but be aware that
701  * the i.MX35 has a slightly different register layout for bits
702  * we do not use here.
703  */
704 static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
705 {
706 	unsigned int val = 0;
707 
708 	if (enable & MXC_INT_TE)
709 		val |= MX31_INTREG_TEEN;
710 	if (enable & MXC_INT_RR)
711 		val |= MX31_INTREG_RREN;
712 
713 	writel(val, spi_imx->base + MXC_CSPIINT);
714 }
715 
716 static void mx31_trigger(struct spi_imx_data *spi_imx)
717 {
718 	unsigned int reg;
719 
720 	reg = readl(spi_imx->base + MXC_CSPICTRL);
721 	reg |= MX31_CSPICTRL_XCH;
722 	writel(reg, spi_imx->base + MXC_CSPICTRL);
723 }
724 
725 static int mx31_prepare_message(struct spi_imx_data *spi_imx,
726 				struct spi_message *msg)
727 {
728 	return 0;
729 }
730 
731 static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
732 				 struct spi_device *spi)
733 {
734 	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
735 	unsigned int clk;
736 
737 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
738 		MX31_CSPICTRL_DR_SHIFT;
739 	spi_imx->spi_bus_clk = clk;
740 
741 	if (is_imx35_cspi(spi_imx)) {
742 		reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
743 		reg |= MX31_CSPICTRL_SSCTL;
744 	} else {
745 		reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
746 	}
747 
748 	if (spi->mode & SPI_CPHA)
749 		reg |= MX31_CSPICTRL_PHA;
750 	if (spi->mode & SPI_CPOL)
751 		reg |= MX31_CSPICTRL_POL;
752 	if (spi->mode & SPI_CS_HIGH)
753 		reg |= MX31_CSPICTRL_SSPOL;
754 	if (!spi->cs_gpiod)
755 		reg |= (spi->chip_select) <<
756 			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
757 						  MX31_CSPICTRL_CS_SHIFT);
758 
759 	if (spi_imx->usedma)
760 		reg |= MX31_CSPICTRL_SMC;
761 
762 	writel(reg, spi_imx->base + MXC_CSPICTRL);
763 
764 	reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
765 	if (spi->mode & SPI_LOOP)
766 		reg |= MX31_TEST_LBC;
767 	else
768 		reg &= ~MX31_TEST_LBC;
769 	writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
770 
771 	if (spi_imx->usedma) {
772 		/*
773 		 * configure DMA requests when RXFIFO is half full and
774 		 * when TXFIFO is half empty
775 		 */
776 		writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
777 			spi_imx->base + MX31_CSPI_DMAREG);
778 	}
779 
780 	return 0;
781 }
782 
783 static int mx31_rx_available(struct spi_imx_data *spi_imx)
784 {
785 	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
786 }
787 
788 static void mx31_reset(struct spi_imx_data *spi_imx)
789 {
790 	/* drain receive buffer */
791 	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
792 		readl(spi_imx->base + MXC_CSPIRXDATA);
793 }
794 
795 #define MX21_INTREG_RR		(1 << 4)
796 #define MX21_INTREG_TEEN	(1 << 9)
797 #define MX21_INTREG_RREN	(1 << 13)
798 
799 #define MX21_CSPICTRL_POL	(1 << 5)
800 #define MX21_CSPICTRL_PHA	(1 << 6)
801 #define MX21_CSPICTRL_SSPOL	(1 << 8)
802 #define MX21_CSPICTRL_XCH	(1 << 9)
803 #define MX21_CSPICTRL_ENABLE	(1 << 10)
804 #define MX21_CSPICTRL_MASTER	(1 << 11)
805 #define MX21_CSPICTRL_DR_SHIFT	14
806 #define MX21_CSPICTRL_CS_SHIFT	19
807 
808 static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
809 {
810 	unsigned int val = 0;
811 
812 	if (enable & MXC_INT_TE)
813 		val |= MX21_INTREG_TEEN;
814 	if (enable & MXC_INT_RR)
815 		val |= MX21_INTREG_RREN;
816 
817 	writel(val, spi_imx->base + MXC_CSPIINT);
818 }
819 
820 static void mx21_trigger(struct spi_imx_data *spi_imx)
821 {
822 	unsigned int reg;
823 
824 	reg = readl(spi_imx->base + MXC_CSPICTRL);
825 	reg |= MX21_CSPICTRL_XCH;
826 	writel(reg, spi_imx->base + MXC_CSPICTRL);
827 }
828 
829 static int mx21_prepare_message(struct spi_imx_data *spi_imx,
830 				struct spi_message *msg)
831 {
832 	return 0;
833 }
834 
835 static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
836 				 struct spi_device *spi)
837 {
838 	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
839 	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
840 	unsigned int clk;
841 
842 	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, spi_imx->spi_bus_clk, max, &clk)
843 		<< MX21_CSPICTRL_DR_SHIFT;
844 	spi_imx->spi_bus_clk = clk;
845 
846 	reg |= spi_imx->bits_per_word - 1;
847 
848 	if (spi->mode & SPI_CPHA)
849 		reg |= MX21_CSPICTRL_PHA;
850 	if (spi->mode & SPI_CPOL)
851 		reg |= MX21_CSPICTRL_POL;
852 	if (spi->mode & SPI_CS_HIGH)
853 		reg |= MX21_CSPICTRL_SSPOL;
854 	if (!spi->cs_gpiod)
855 		reg |= spi->chip_select << MX21_CSPICTRL_CS_SHIFT;
856 
857 	writel(reg, spi_imx->base + MXC_CSPICTRL);
858 
859 	return 0;
860 }
861 
862 static int mx21_rx_available(struct spi_imx_data *spi_imx)
863 {
864 	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
865 }
866 
867 static void mx21_reset(struct spi_imx_data *spi_imx)
868 {
869 	writel(1, spi_imx->base + MXC_RESET);
870 }
871 
872 #define MX1_INTREG_RR		(1 << 3)
873 #define MX1_INTREG_TEEN		(1 << 8)
874 #define MX1_INTREG_RREN		(1 << 11)
875 
876 #define MX1_CSPICTRL_POL	(1 << 4)
877 #define MX1_CSPICTRL_PHA	(1 << 5)
878 #define MX1_CSPICTRL_XCH	(1 << 8)
879 #define MX1_CSPICTRL_ENABLE	(1 << 9)
880 #define MX1_CSPICTRL_MASTER	(1 << 10)
881 #define MX1_CSPICTRL_DR_SHIFT	13
882 
883 static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
884 {
885 	unsigned int val = 0;
886 
887 	if (enable & MXC_INT_TE)
888 		val |= MX1_INTREG_TEEN;
889 	if (enable & MXC_INT_RR)
890 		val |= MX1_INTREG_RREN;
891 
892 	writel(val, spi_imx->base + MXC_CSPIINT);
893 }
894 
895 static void mx1_trigger(struct spi_imx_data *spi_imx)
896 {
897 	unsigned int reg;
898 
899 	reg = readl(spi_imx->base + MXC_CSPICTRL);
900 	reg |= MX1_CSPICTRL_XCH;
901 	writel(reg, spi_imx->base + MXC_CSPICTRL);
902 }
903 
904 static int mx1_prepare_message(struct spi_imx_data *spi_imx,
905 			       struct spi_message *msg)
906 {
907 	return 0;
908 }
909 
910 static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
911 				struct spi_device *spi)
912 {
913 	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
914 	unsigned int clk;
915 
916 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
917 		MX1_CSPICTRL_DR_SHIFT;
918 	spi_imx->spi_bus_clk = clk;
919 
920 	reg |= spi_imx->bits_per_word - 1;
921 
922 	if (spi->mode & SPI_CPHA)
923 		reg |= MX1_CSPICTRL_PHA;
924 	if (spi->mode & SPI_CPOL)
925 		reg |= MX1_CSPICTRL_POL;
926 
927 	writel(reg, spi_imx->base + MXC_CSPICTRL);
928 
929 	return 0;
930 }
931 
932 static int mx1_rx_available(struct spi_imx_data *spi_imx)
933 {
934 	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
935 }
936 
937 static void mx1_reset(struct spi_imx_data *spi_imx)
938 {
939 	writel(1, spi_imx->base + MXC_RESET);
940 }
941 
942 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
943 	.intctrl = mx1_intctrl,
944 	.prepare_message = mx1_prepare_message,
945 	.prepare_transfer = mx1_prepare_transfer,
946 	.trigger = mx1_trigger,
947 	.rx_available = mx1_rx_available,
948 	.reset = mx1_reset,
949 	.fifo_size = 8,
950 	.has_dmamode = false,
951 	.dynamic_burst = false,
952 	.has_slavemode = false,
953 	.devtype = IMX1_CSPI,
954 };
955 
956 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
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 = IMX21_CSPI,
968 };
969 
970 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
971 	/* i.mx27 cspi shares the functions with i.mx21 one */
972 	.intctrl = mx21_intctrl,
973 	.prepare_message = mx21_prepare_message,
974 	.prepare_transfer = mx21_prepare_transfer,
975 	.trigger = mx21_trigger,
976 	.rx_available = mx21_rx_available,
977 	.reset = mx21_reset,
978 	.fifo_size = 8,
979 	.has_dmamode = false,
980 	.dynamic_burst = false,
981 	.has_slavemode = false,
982 	.devtype = IMX27_CSPI,
983 };
984 
985 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
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 = false,
994 	.dynamic_burst = false,
995 	.has_slavemode = false,
996 	.devtype = IMX31_CSPI,
997 };
998 
999 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
1000 	/* i.mx35 and later cspi shares the functions with i.mx31 one */
1001 	.intctrl = mx31_intctrl,
1002 	.prepare_message = mx31_prepare_message,
1003 	.prepare_transfer = mx31_prepare_transfer,
1004 	.trigger = mx31_trigger,
1005 	.rx_available = mx31_rx_available,
1006 	.reset = mx31_reset,
1007 	.fifo_size = 8,
1008 	.has_dmamode = true,
1009 	.dynamic_burst = false,
1010 	.has_slavemode = false,
1011 	.devtype = IMX35_CSPI,
1012 };
1013 
1014 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
1015 	.intctrl = mx51_ecspi_intctrl,
1016 	.prepare_message = mx51_ecspi_prepare_message,
1017 	.prepare_transfer = mx51_ecspi_prepare_transfer,
1018 	.trigger = mx51_ecspi_trigger,
1019 	.rx_available = mx51_ecspi_rx_available,
1020 	.reset = mx51_ecspi_reset,
1021 	.setup_wml = mx51_setup_wml,
1022 	.disable_dma = mx51_disable_dma,
1023 	.fifo_size = 64,
1024 	.has_dmamode = true,
1025 	.dynamic_burst = true,
1026 	.has_slavemode = true,
1027 	.disable = mx51_ecspi_disable,
1028 	.devtype = IMX51_ECSPI,
1029 };
1030 
1031 static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
1032 	.intctrl = mx51_ecspi_intctrl,
1033 	.prepare_message = mx51_ecspi_prepare_message,
1034 	.prepare_transfer = mx51_ecspi_prepare_transfer,
1035 	.trigger = mx51_ecspi_trigger,
1036 	.rx_available = mx51_ecspi_rx_available,
1037 	.disable_dma = mx51_disable_dma,
1038 	.reset = mx51_ecspi_reset,
1039 	.fifo_size = 64,
1040 	.has_dmamode = true,
1041 	.has_slavemode = true,
1042 	.disable = mx51_ecspi_disable,
1043 	.devtype = IMX53_ECSPI,
1044 };
1045 
1046 static struct spi_imx_devtype_data imx6ul_ecspi_devtype_data = {
1047 	.intctrl = mx51_ecspi_intctrl,
1048 	.prepare_message = mx51_ecspi_prepare_message,
1049 	.prepare_transfer = mx51_ecspi_prepare_transfer,
1050 	.trigger = mx51_ecspi_trigger,
1051 	.rx_available = mx51_ecspi_rx_available,
1052 	.reset = mx51_ecspi_reset,
1053 	.setup_wml = mx51_setup_wml,
1054 	.fifo_size = 64,
1055 	.has_dmamode = true,
1056 	.dynamic_burst = true,
1057 	.has_slavemode = true,
1058 	.tx_glitch_fixed = true,
1059 	.disable = mx51_ecspi_disable,
1060 	.devtype = IMX51_ECSPI,
1061 };
1062 
1063 static const struct of_device_id spi_imx_dt_ids[] = {
1064 	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
1065 	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
1066 	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
1067 	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
1068 	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
1069 	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
1070 	{ .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
1071 	{ .compatible = "fsl,imx6ul-ecspi", .data = &imx6ul_ecspi_devtype_data, },
1072 	{ /* sentinel */ }
1073 };
1074 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
1075 
1076 static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
1077 {
1078 	u32 ctrl;
1079 
1080 	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
1081 	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
1082 	ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
1083 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
1084 }
1085 
1086 static void spi_imx_push(struct spi_imx_data *spi_imx)
1087 {
1088 	unsigned int burst_len;
1089 
1090 	/*
1091 	 * Reload the FIFO when the remaining bytes to be transferred in the
1092 	 * current burst is 0. This only applies when bits_per_word is a
1093 	 * multiple of 8.
1094 	 */
1095 	if (!spi_imx->remainder) {
1096 		if (spi_imx->dynamic_burst) {
1097 
1098 			/* We need to deal unaligned data first */
1099 			burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
1100 
1101 			if (!burst_len)
1102 				burst_len = MX51_ECSPI_CTRL_MAX_BURST;
1103 
1104 			spi_imx_set_burst_len(spi_imx, burst_len * 8);
1105 
1106 			spi_imx->remainder = burst_len;
1107 		} else {
1108 			spi_imx->remainder = spi_imx_bytes_per_word(spi_imx->bits_per_word);
1109 		}
1110 	}
1111 
1112 	while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
1113 		if (!spi_imx->count)
1114 			break;
1115 		if (spi_imx->dynamic_burst &&
1116 		    spi_imx->txfifo >= DIV_ROUND_UP(spi_imx->remainder, 4))
1117 			break;
1118 		spi_imx->tx(spi_imx);
1119 		spi_imx->txfifo++;
1120 	}
1121 
1122 	if (!spi_imx->slave_mode)
1123 		spi_imx->devtype_data->trigger(spi_imx);
1124 }
1125 
1126 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
1127 {
1128 	struct spi_imx_data *spi_imx = dev_id;
1129 
1130 	while (spi_imx->txfifo &&
1131 	       spi_imx->devtype_data->rx_available(spi_imx)) {
1132 		spi_imx->rx(spi_imx);
1133 		spi_imx->txfifo--;
1134 	}
1135 
1136 	if (spi_imx->count) {
1137 		spi_imx_push(spi_imx);
1138 		return IRQ_HANDLED;
1139 	}
1140 
1141 	if (spi_imx->txfifo) {
1142 		/* No data left to push, but still waiting for rx data,
1143 		 * enable receive data available interrupt.
1144 		 */
1145 		spi_imx->devtype_data->intctrl(
1146 				spi_imx, MXC_INT_RR);
1147 		return IRQ_HANDLED;
1148 	}
1149 
1150 	spi_imx->devtype_data->intctrl(spi_imx, 0);
1151 	complete(&spi_imx->xfer_done);
1152 
1153 	return IRQ_HANDLED;
1154 }
1155 
1156 static int spi_imx_dma_configure(struct spi_master *master)
1157 {
1158 	int ret;
1159 	enum dma_slave_buswidth buswidth;
1160 	struct dma_slave_config rx = {}, tx = {};
1161 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1162 
1163 	switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
1164 	case 4:
1165 		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
1166 		break;
1167 	case 2:
1168 		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
1169 		break;
1170 	case 1:
1171 		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
1172 		break;
1173 	default:
1174 		return -EINVAL;
1175 	}
1176 
1177 	tx.direction = DMA_MEM_TO_DEV;
1178 	tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
1179 	tx.dst_addr_width = buswidth;
1180 	tx.dst_maxburst = spi_imx->wml;
1181 	ret = dmaengine_slave_config(master->dma_tx, &tx);
1182 	if (ret) {
1183 		dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
1184 		return ret;
1185 	}
1186 
1187 	rx.direction = DMA_DEV_TO_MEM;
1188 	rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
1189 	rx.src_addr_width = buswidth;
1190 	rx.src_maxburst = spi_imx->wml;
1191 	ret = dmaengine_slave_config(master->dma_rx, &rx);
1192 	if (ret) {
1193 		dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
1194 		return ret;
1195 	}
1196 
1197 	return 0;
1198 }
1199 
1200 static int spi_imx_setupxfer(struct spi_device *spi,
1201 				 struct spi_transfer *t)
1202 {
1203 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1204 
1205 	if (!t)
1206 		return 0;
1207 
1208 	if (!t->speed_hz) {
1209 		if (!spi->max_speed_hz) {
1210 			dev_err(&spi->dev, "no speed_hz provided!\n");
1211 			return -EINVAL;
1212 		}
1213 		dev_dbg(&spi->dev, "using spi->max_speed_hz!\n");
1214 		spi_imx->spi_bus_clk = spi->max_speed_hz;
1215 	} else
1216 		spi_imx->spi_bus_clk = t->speed_hz;
1217 
1218 	spi_imx->bits_per_word = t->bits_per_word;
1219 
1220 	/*
1221 	 * Initialize the functions for transfer. To transfer non byte-aligned
1222 	 * words, we have to use multiple word-size bursts, we can't use
1223 	 * dynamic_burst in that case.
1224 	 */
1225 	if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode &&
1226 	    !(spi->mode & SPI_CS_WORD) &&
1227 	    (spi_imx->bits_per_word == 8 ||
1228 	    spi_imx->bits_per_word == 16 ||
1229 	    spi_imx->bits_per_word == 32)) {
1230 
1231 		spi_imx->rx = spi_imx_buf_rx_swap;
1232 		spi_imx->tx = spi_imx_buf_tx_swap;
1233 		spi_imx->dynamic_burst = 1;
1234 
1235 	} else {
1236 		if (spi_imx->bits_per_word <= 8) {
1237 			spi_imx->rx = spi_imx_buf_rx_u8;
1238 			spi_imx->tx = spi_imx_buf_tx_u8;
1239 		} else if (spi_imx->bits_per_word <= 16) {
1240 			spi_imx->rx = spi_imx_buf_rx_u16;
1241 			spi_imx->tx = spi_imx_buf_tx_u16;
1242 		} else {
1243 			spi_imx->rx = spi_imx_buf_rx_u32;
1244 			spi_imx->tx = spi_imx_buf_tx_u32;
1245 		}
1246 		spi_imx->dynamic_burst = 0;
1247 	}
1248 
1249 	if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
1250 		spi_imx->usedma = true;
1251 	else
1252 		spi_imx->usedma = false;
1253 
1254 	if (is_imx53_ecspi(spi_imx) && spi_imx->slave_mode) {
1255 		spi_imx->rx = mx53_ecspi_rx_slave;
1256 		spi_imx->tx = mx53_ecspi_tx_slave;
1257 		spi_imx->slave_burst = t->len;
1258 	}
1259 
1260 	spi_imx->devtype_data->prepare_transfer(spi_imx, spi);
1261 
1262 	return 0;
1263 }
1264 
1265 static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
1266 {
1267 	struct spi_master *master = spi_imx->bitbang.master;
1268 
1269 	if (master->dma_rx) {
1270 		dma_release_channel(master->dma_rx);
1271 		master->dma_rx = NULL;
1272 	}
1273 
1274 	if (master->dma_tx) {
1275 		dma_release_channel(master->dma_tx);
1276 		master->dma_tx = NULL;
1277 	}
1278 }
1279 
1280 static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
1281 			     struct spi_master *master)
1282 {
1283 	int ret;
1284 
1285 	spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
1286 
1287 	/* Prepare for TX DMA: */
1288 	master->dma_tx = dma_request_chan(dev, "tx");
1289 	if (IS_ERR(master->dma_tx)) {
1290 		ret = PTR_ERR(master->dma_tx);
1291 		dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
1292 		master->dma_tx = NULL;
1293 		goto err;
1294 	}
1295 
1296 	/* Prepare for RX : */
1297 	master->dma_rx = dma_request_chan(dev, "rx");
1298 	if (IS_ERR(master->dma_rx)) {
1299 		ret = PTR_ERR(master->dma_rx);
1300 		dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
1301 		master->dma_rx = NULL;
1302 		goto err;
1303 	}
1304 
1305 	init_completion(&spi_imx->dma_rx_completion);
1306 	init_completion(&spi_imx->dma_tx_completion);
1307 	master->can_dma = spi_imx_can_dma;
1308 	master->max_dma_len = MAX_SDMA_BD_BYTES;
1309 	spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
1310 					 SPI_MASTER_MUST_TX;
1311 
1312 	return 0;
1313 err:
1314 	spi_imx_sdma_exit(spi_imx);
1315 	return ret;
1316 }
1317 
1318 static void spi_imx_dma_rx_callback(void *cookie)
1319 {
1320 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1321 
1322 	complete(&spi_imx->dma_rx_completion);
1323 }
1324 
1325 static void spi_imx_dma_tx_callback(void *cookie)
1326 {
1327 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1328 
1329 	complete(&spi_imx->dma_tx_completion);
1330 }
1331 
1332 static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1333 {
1334 	unsigned long timeout = 0;
1335 
1336 	/* Time with actual data transfer and CS change delay related to HW */
1337 	timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1338 
1339 	/* Add extra second for scheduler related activities */
1340 	timeout += 1;
1341 
1342 	/* Double calculated timeout */
1343 	return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1344 }
1345 
1346 static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1347 				struct spi_transfer *transfer)
1348 {
1349 	struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1350 	unsigned long transfer_timeout;
1351 	unsigned long timeout;
1352 	struct spi_master *master = spi_imx->bitbang.master;
1353 	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1354 	struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
1355 	unsigned int bytes_per_word, i;
1356 	int ret;
1357 
1358 	/* Get the right burst length from the last sg to ensure no tail data */
1359 	bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
1360 	for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
1361 		if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
1362 			break;
1363 	}
1364 	/* Use 1 as wml in case no available burst length got */
1365 	if (i == 0)
1366 		i = 1;
1367 
1368 	spi_imx->wml =  i;
1369 
1370 	ret = spi_imx_dma_configure(master);
1371 	if (ret)
1372 		goto dma_failure_no_start;
1373 
1374 	if (!spi_imx->devtype_data->setup_wml) {
1375 		dev_err(spi_imx->dev, "No setup_wml()?\n");
1376 		ret = -EINVAL;
1377 		goto dma_failure_no_start;
1378 	}
1379 	spi_imx->devtype_data->setup_wml(spi_imx);
1380 
1381 	/*
1382 	 * The TX DMA setup starts the transfer, so make sure RX is configured
1383 	 * before TX.
1384 	 */
1385 	desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
1386 				rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1387 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1388 	if (!desc_rx) {
1389 		ret = -EINVAL;
1390 		goto dma_failure_no_start;
1391 	}
1392 
1393 	desc_rx->callback = spi_imx_dma_rx_callback;
1394 	desc_rx->callback_param = (void *)spi_imx;
1395 	dmaengine_submit(desc_rx);
1396 	reinit_completion(&spi_imx->dma_rx_completion);
1397 	dma_async_issue_pending(master->dma_rx);
1398 
1399 	desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
1400 				tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1401 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1402 	if (!desc_tx) {
1403 		dmaengine_terminate_all(master->dma_tx);
1404 		dmaengine_terminate_all(master->dma_rx);
1405 		return -EINVAL;
1406 	}
1407 
1408 	desc_tx->callback = spi_imx_dma_tx_callback;
1409 	desc_tx->callback_param = (void *)spi_imx;
1410 	dmaengine_submit(desc_tx);
1411 	reinit_completion(&spi_imx->dma_tx_completion);
1412 	dma_async_issue_pending(master->dma_tx);
1413 
1414 	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1415 
1416 	/* Wait SDMA to finish the data transfer.*/
1417 	timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1418 						transfer_timeout);
1419 	if (!timeout) {
1420 		dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1421 		dmaengine_terminate_all(master->dma_tx);
1422 		dmaengine_terminate_all(master->dma_rx);
1423 		return -ETIMEDOUT;
1424 	}
1425 
1426 	timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1427 					      transfer_timeout);
1428 	if (!timeout) {
1429 		dev_err(&master->dev, "I/O Error in DMA RX\n");
1430 		spi_imx->devtype_data->reset(spi_imx);
1431 		dmaengine_terminate_all(master->dma_rx);
1432 		return -ETIMEDOUT;
1433 	}
1434 
1435 	return transfer->len;
1436 /* fallback to pio */
1437 dma_failure_no_start:
1438 	transfer->error |= SPI_TRANS_FAIL_NO_START;
1439 	return ret;
1440 }
1441 
1442 static int spi_imx_pio_transfer(struct spi_device *spi,
1443 				struct spi_transfer *transfer)
1444 {
1445 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1446 	unsigned long transfer_timeout;
1447 	unsigned long timeout;
1448 
1449 	spi_imx->tx_buf = transfer->tx_buf;
1450 	spi_imx->rx_buf = transfer->rx_buf;
1451 	spi_imx->count = transfer->len;
1452 	spi_imx->txfifo = 0;
1453 	spi_imx->remainder = 0;
1454 
1455 	reinit_completion(&spi_imx->xfer_done);
1456 
1457 	spi_imx_push(spi_imx);
1458 
1459 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1460 
1461 	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1462 
1463 	timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
1464 					      transfer_timeout);
1465 	if (!timeout) {
1466 		dev_err(&spi->dev, "I/O Error in PIO\n");
1467 		spi_imx->devtype_data->reset(spi_imx);
1468 		return -ETIMEDOUT;
1469 	}
1470 
1471 	return transfer->len;
1472 }
1473 
1474 static int spi_imx_pio_transfer_slave(struct spi_device *spi,
1475 				      struct spi_transfer *transfer)
1476 {
1477 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1478 	int ret = transfer->len;
1479 
1480 	if (is_imx53_ecspi(spi_imx) &&
1481 	    transfer->len > MX53_MAX_TRANSFER_BYTES) {
1482 		dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
1483 			MX53_MAX_TRANSFER_BYTES);
1484 		return -EMSGSIZE;
1485 	}
1486 
1487 	spi_imx->tx_buf = transfer->tx_buf;
1488 	spi_imx->rx_buf = transfer->rx_buf;
1489 	spi_imx->count = transfer->len;
1490 	spi_imx->txfifo = 0;
1491 	spi_imx->remainder = 0;
1492 
1493 	reinit_completion(&spi_imx->xfer_done);
1494 	spi_imx->slave_aborted = false;
1495 
1496 	spi_imx_push(spi_imx);
1497 
1498 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
1499 
1500 	if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
1501 	    spi_imx->slave_aborted) {
1502 		dev_dbg(&spi->dev, "interrupted\n");
1503 		ret = -EINTR;
1504 	}
1505 
1506 	/* ecspi has a HW issue when works in Slave mode,
1507 	 * after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
1508 	 * ECSPI_TXDATA keeps shift out the last word data,
1509 	 * so we have to disable ECSPI when in slave mode after the
1510 	 * transfer completes
1511 	 */
1512 	if (spi_imx->devtype_data->disable)
1513 		spi_imx->devtype_data->disable(spi_imx);
1514 
1515 	return ret;
1516 }
1517 
1518 static int spi_imx_transfer(struct spi_device *spi,
1519 				struct spi_transfer *transfer)
1520 {
1521 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1522 
1523 	transfer->effective_speed_hz = spi_imx->spi_bus_clk;
1524 
1525 	/* flush rxfifo before transfer */
1526 	while (spi_imx->devtype_data->rx_available(spi_imx))
1527 		readl(spi_imx->base + MXC_CSPIRXDATA);
1528 
1529 	if (spi_imx->slave_mode)
1530 		return spi_imx_pio_transfer_slave(spi, transfer);
1531 
1532 	if (spi_imx->usedma)
1533 		return spi_imx_dma_transfer(spi_imx, transfer);
1534 
1535 	return spi_imx_pio_transfer(spi, transfer);
1536 }
1537 
1538 static int spi_imx_setup(struct spi_device *spi)
1539 {
1540 	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1541 		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1542 
1543 	return 0;
1544 }
1545 
1546 static void spi_imx_cleanup(struct spi_device *spi)
1547 {
1548 }
1549 
1550 static int
1551 spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1552 {
1553 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1554 	int ret;
1555 
1556 	ret = pm_runtime_get_sync(spi_imx->dev);
1557 	if (ret < 0) {
1558 		pm_runtime_put_noidle(spi_imx->dev);
1559 		dev_err(spi_imx->dev, "failed to enable clock\n");
1560 		return ret;
1561 	}
1562 
1563 	ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
1564 	if (ret) {
1565 		pm_runtime_mark_last_busy(spi_imx->dev);
1566 		pm_runtime_put_autosuspend(spi_imx->dev);
1567 	}
1568 
1569 	return ret;
1570 }
1571 
1572 static int
1573 spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1574 {
1575 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1576 
1577 	pm_runtime_mark_last_busy(spi_imx->dev);
1578 	pm_runtime_put_autosuspend(spi_imx->dev);
1579 	return 0;
1580 }
1581 
1582 static int spi_imx_slave_abort(struct spi_master *master)
1583 {
1584 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1585 
1586 	spi_imx->slave_aborted = true;
1587 	complete(&spi_imx->xfer_done);
1588 
1589 	return 0;
1590 }
1591 
1592 static int spi_imx_probe(struct platform_device *pdev)
1593 {
1594 	struct device_node *np = pdev->dev.of_node;
1595 	struct spi_master *master;
1596 	struct spi_imx_data *spi_imx;
1597 	struct resource *res;
1598 	int ret, irq, spi_drctl;
1599 	const struct spi_imx_devtype_data *devtype_data =
1600 			of_device_get_match_data(&pdev->dev);
1601 	bool slave_mode;
1602 	u32 val;
1603 
1604 	slave_mode = devtype_data->has_slavemode &&
1605 			of_property_read_bool(np, "spi-slave");
1606 	if (slave_mode)
1607 		master = spi_alloc_slave(&pdev->dev,
1608 					 sizeof(struct spi_imx_data));
1609 	else
1610 		master = spi_alloc_master(&pdev->dev,
1611 					  sizeof(struct spi_imx_data));
1612 	if (!master)
1613 		return -ENOMEM;
1614 
1615 	ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
1616 	if ((ret < 0) || (spi_drctl >= 0x3)) {
1617 		/* '11' is reserved */
1618 		spi_drctl = 0;
1619 	}
1620 
1621 	platform_set_drvdata(pdev, master);
1622 
1623 	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1624 	master->bus_num = np ? -1 : pdev->id;
1625 	master->use_gpio_descriptors = true;
1626 
1627 	spi_imx = spi_master_get_devdata(master);
1628 	spi_imx->bitbang.master = master;
1629 	spi_imx->dev = &pdev->dev;
1630 	spi_imx->slave_mode = slave_mode;
1631 
1632 	spi_imx->devtype_data = devtype_data;
1633 
1634 	/*
1635 	 * Get number of chip selects from device properties. This can be
1636 	 * coming from device tree or boardfiles, if it is not defined,
1637 	 * a default value of 3 chip selects will be used, as all the legacy
1638 	 * board files have <= 3 chip selects.
1639 	 */
1640 	if (!device_property_read_u32(&pdev->dev, "num-cs", &val))
1641 		master->num_chipselect = val;
1642 	else
1643 		master->num_chipselect = 3;
1644 
1645 	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1646 	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1647 	spi_imx->bitbang.master->setup = spi_imx_setup;
1648 	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1649 	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1650 	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1651 	spi_imx->bitbang.master->slave_abort = spi_imx_slave_abort;
1652 	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
1653 					     | SPI_NO_CS;
1654 	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
1655 	    is_imx53_ecspi(spi_imx))
1656 		spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY;
1657 
1658 	if (is_imx51_ecspi(spi_imx) &&
1659 	    device_property_read_u32(&pdev->dev, "cs-gpios", NULL))
1660 		/*
1661 		 * When using HW-CS implementing SPI_CS_WORD can be done by just
1662 		 * setting the burst length to the word size. This is
1663 		 * considerably faster than manually controlling the CS.
1664 		 */
1665 		spi_imx->bitbang.master->mode_bits |= SPI_CS_WORD;
1666 
1667 	spi_imx->spi_drctl = spi_drctl;
1668 
1669 	init_completion(&spi_imx->xfer_done);
1670 
1671 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1672 	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1673 	if (IS_ERR(spi_imx->base)) {
1674 		ret = PTR_ERR(spi_imx->base);
1675 		goto out_master_put;
1676 	}
1677 	spi_imx->base_phys = res->start;
1678 
1679 	irq = platform_get_irq(pdev, 0);
1680 	if (irq < 0) {
1681 		ret = irq;
1682 		goto out_master_put;
1683 	}
1684 
1685 	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1686 			       dev_name(&pdev->dev), spi_imx);
1687 	if (ret) {
1688 		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1689 		goto out_master_put;
1690 	}
1691 
1692 	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1693 	if (IS_ERR(spi_imx->clk_ipg)) {
1694 		ret = PTR_ERR(spi_imx->clk_ipg);
1695 		goto out_master_put;
1696 	}
1697 
1698 	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1699 	if (IS_ERR(spi_imx->clk_per)) {
1700 		ret = PTR_ERR(spi_imx->clk_per);
1701 		goto out_master_put;
1702 	}
1703 
1704 	ret = clk_prepare_enable(spi_imx->clk_per);
1705 	if (ret)
1706 		goto out_master_put;
1707 
1708 	ret = clk_prepare_enable(spi_imx->clk_ipg);
1709 	if (ret)
1710 		goto out_put_per;
1711 
1712 	pm_runtime_set_autosuspend_delay(spi_imx->dev, MXC_RPM_TIMEOUT);
1713 	pm_runtime_use_autosuspend(spi_imx->dev);
1714 	pm_runtime_get_noresume(spi_imx->dev);
1715 	pm_runtime_set_active(spi_imx->dev);
1716 	pm_runtime_enable(spi_imx->dev);
1717 
1718 	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1719 	/*
1720 	 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1721 	 * if validated on other chips.
1722 	 */
1723 	if (spi_imx->devtype_data->has_dmamode) {
1724 		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
1725 		if (ret == -EPROBE_DEFER)
1726 			goto out_runtime_pm_put;
1727 
1728 		if (ret < 0)
1729 			dev_dbg(&pdev->dev, "dma setup error %d, use pio\n",
1730 				ret);
1731 	}
1732 
1733 	spi_imx->devtype_data->reset(spi_imx);
1734 
1735 	spi_imx->devtype_data->intctrl(spi_imx, 0);
1736 
1737 	master->dev.of_node = pdev->dev.of_node;
1738 	ret = spi_bitbang_start(&spi_imx->bitbang);
1739 	if (ret) {
1740 		dev_err_probe(&pdev->dev, ret, "bitbang start failed\n");
1741 		goto out_bitbang_start;
1742 	}
1743 
1744 	pm_runtime_mark_last_busy(spi_imx->dev);
1745 	pm_runtime_put_autosuspend(spi_imx->dev);
1746 
1747 	return ret;
1748 
1749 out_bitbang_start:
1750 	if (spi_imx->devtype_data->has_dmamode)
1751 		spi_imx_sdma_exit(spi_imx);
1752 out_runtime_pm_put:
1753 	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1754 	pm_runtime_set_suspended(&pdev->dev);
1755 	pm_runtime_disable(spi_imx->dev);
1756 
1757 	clk_disable_unprepare(spi_imx->clk_ipg);
1758 out_put_per:
1759 	clk_disable_unprepare(spi_imx->clk_per);
1760 out_master_put:
1761 	spi_master_put(master);
1762 
1763 	return ret;
1764 }
1765 
1766 static int spi_imx_remove(struct platform_device *pdev)
1767 {
1768 	struct spi_master *master = platform_get_drvdata(pdev);
1769 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1770 	int ret;
1771 
1772 	spi_bitbang_stop(&spi_imx->bitbang);
1773 
1774 	ret = pm_runtime_get_sync(spi_imx->dev);
1775 	if (ret < 0) {
1776 		pm_runtime_put_noidle(spi_imx->dev);
1777 		dev_err(spi_imx->dev, "failed to enable clock\n");
1778 		return ret;
1779 	}
1780 
1781 	writel(0, spi_imx->base + MXC_CSPICTRL);
1782 
1783 	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1784 	pm_runtime_put_sync(spi_imx->dev);
1785 	pm_runtime_disable(spi_imx->dev);
1786 
1787 	spi_imx_sdma_exit(spi_imx);
1788 	spi_master_put(master);
1789 
1790 	return 0;
1791 }
1792 
1793 static int __maybe_unused spi_imx_runtime_resume(struct device *dev)
1794 {
1795 	struct spi_master *master = dev_get_drvdata(dev);
1796 	struct spi_imx_data *spi_imx;
1797 	int ret;
1798 
1799 	spi_imx = spi_master_get_devdata(master);
1800 
1801 	ret = clk_prepare_enable(spi_imx->clk_per);
1802 	if (ret)
1803 		return ret;
1804 
1805 	ret = clk_prepare_enable(spi_imx->clk_ipg);
1806 	if (ret) {
1807 		clk_disable_unprepare(spi_imx->clk_per);
1808 		return ret;
1809 	}
1810 
1811 	return 0;
1812 }
1813 
1814 static int __maybe_unused spi_imx_runtime_suspend(struct device *dev)
1815 {
1816 	struct spi_master *master = dev_get_drvdata(dev);
1817 	struct spi_imx_data *spi_imx;
1818 
1819 	spi_imx = spi_master_get_devdata(master);
1820 
1821 	clk_disable_unprepare(spi_imx->clk_per);
1822 	clk_disable_unprepare(spi_imx->clk_ipg);
1823 
1824 	return 0;
1825 }
1826 
1827 static int __maybe_unused spi_imx_suspend(struct device *dev)
1828 {
1829 	pinctrl_pm_select_sleep_state(dev);
1830 	return 0;
1831 }
1832 
1833 static int __maybe_unused spi_imx_resume(struct device *dev)
1834 {
1835 	pinctrl_pm_select_default_state(dev);
1836 	return 0;
1837 }
1838 
1839 static const struct dev_pm_ops imx_spi_pm = {
1840 	SET_RUNTIME_PM_OPS(spi_imx_runtime_suspend,
1841 				spi_imx_runtime_resume, NULL)
1842 	SET_SYSTEM_SLEEP_PM_OPS(spi_imx_suspend, spi_imx_resume)
1843 };
1844 
1845 static struct platform_driver spi_imx_driver = {
1846 	.driver = {
1847 		   .name = DRIVER_NAME,
1848 		   .of_match_table = spi_imx_dt_ids,
1849 		   .pm = &imx_spi_pm,
1850 	},
1851 	.probe = spi_imx_probe,
1852 	.remove = spi_imx_remove,
1853 };
1854 module_platform_driver(spi_imx_driver);
1855 
1856 MODULE_DESCRIPTION("i.MX SPI Controller driver");
1857 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1858 MODULE_LICENSE("GPL");
1859 MODULE_ALIAS("platform:" DRIVER_NAME);
1860