xref: /openbmc/linux/drivers/spi/spi-imx.c (revision 724ba675)
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/types.h>
22 #include <linux/of.h>
23 #include <linux/of_device.h>
24 #include <linux/property.h>
25 
26 #include <linux/dma/imx-dma.h>
27 
28 #define DRIVER_NAME "spi_imx"
29 
30 static bool use_dma = true;
31 module_param(use_dma, bool, 0644);
32 MODULE_PARM_DESC(use_dma, "Enable usage of DMA when available (default)");
33 
34 /* define polling limits */
35 static unsigned int polling_limit_us = 30;
36 module_param(polling_limit_us, uint, 0664);
37 MODULE_PARM_DESC(polling_limit_us,
38 		 "time in us to run a transfer in polling mode\n");
39 
40 #define MXC_RPM_TIMEOUT		2000 /* 2000ms */
41 
42 #define MXC_CSPIRXDATA		0x00
43 #define MXC_CSPITXDATA		0x04
44 #define MXC_CSPICTRL		0x08
45 #define MXC_CSPIINT		0x0c
46 #define MXC_RESET		0x1c
47 
48 /* generic defines to abstract from the different register layouts */
49 #define MXC_INT_RR	(1 << 0) /* Receive data ready interrupt */
50 #define MXC_INT_TE	(1 << 1) /* Transmit FIFO empty interrupt */
51 #define MXC_INT_RDR	BIT(4) /* Receive date threshold interrupt */
52 
53 /* The maximum bytes that a sdma BD can transfer. */
54 #define MAX_SDMA_BD_BYTES (1 << 15)
55 #define MX51_ECSPI_CTRL_MAX_BURST	512
56 /* The maximum bytes that IMX53_ECSPI can transfer in slave mode.*/
57 #define MX53_MAX_TRANSFER_BYTES		512
58 
59 enum spi_imx_devtype {
60 	IMX1_CSPI,
61 	IMX21_CSPI,
62 	IMX27_CSPI,
63 	IMX31_CSPI,
64 	IMX35_CSPI,	/* CSPI on all i.mx except above */
65 	IMX51_ECSPI,	/* ECSPI on i.mx51 */
66 	IMX53_ECSPI,	/* ECSPI on i.mx53 and later */
67 };
68 
69 struct spi_imx_data;
70 
71 struct spi_imx_devtype_data {
72 	void (*intctrl)(struct spi_imx_data *spi_imx, int enable);
73 	int (*prepare_message)(struct spi_imx_data *spi_imx, struct spi_message *msg);
74 	int (*prepare_transfer)(struct spi_imx_data *spi_imx, struct spi_device *spi);
75 	void (*trigger)(struct spi_imx_data *spi_imx);
76 	int (*rx_available)(struct spi_imx_data *spi_imx);
77 	void (*reset)(struct spi_imx_data *spi_imx);
78 	void (*setup_wml)(struct spi_imx_data *spi_imx);
79 	void (*disable)(struct spi_imx_data *spi_imx);
80 	bool has_dmamode;
81 	bool has_slavemode;
82 	unsigned int fifo_size;
83 	bool dynamic_burst;
84 	/*
85 	 * ERR009165 fixed or not:
86 	 * https://www.nxp.com/docs/en/errata/IMX6DQCE.pdf
87 	 */
88 	bool tx_glitch_fixed;
89 	enum spi_imx_devtype devtype;
90 };
91 
92 struct spi_imx_data {
93 	struct spi_controller *controller;
94 	struct device *dev;
95 
96 	struct completion xfer_done;
97 	void __iomem *base;
98 	unsigned long base_phys;
99 
100 	struct clk *clk_per;
101 	struct clk *clk_ipg;
102 	unsigned long spi_clk;
103 	unsigned int spi_bus_clk;
104 
105 	unsigned int bits_per_word;
106 	unsigned int spi_drctl;
107 
108 	unsigned int count, remainder;
109 	void (*tx)(struct spi_imx_data *spi_imx);
110 	void (*rx)(struct spi_imx_data *spi_imx);
111 	void *rx_buf;
112 	const void *tx_buf;
113 	unsigned int txfifo; /* number of words pushed in tx FIFO */
114 	unsigned int dynamic_burst;
115 	bool rx_only;
116 
117 	/* Slave mode */
118 	bool slave_mode;
119 	bool slave_aborted;
120 	unsigned int slave_burst;
121 
122 	/* DMA */
123 	bool usedma;
124 	u32 wml;
125 	struct completion dma_rx_completion;
126 	struct completion dma_tx_completion;
127 
128 	const struct spi_imx_devtype_data *devtype_data;
129 };
130 
131 static inline int is_imx27_cspi(struct spi_imx_data *d)
132 {
133 	return d->devtype_data->devtype == IMX27_CSPI;
134 }
135 
136 static inline int is_imx35_cspi(struct spi_imx_data *d)
137 {
138 	return d->devtype_data->devtype == IMX35_CSPI;
139 }
140 
141 static inline int is_imx51_ecspi(struct spi_imx_data *d)
142 {
143 	return d->devtype_data->devtype == IMX51_ECSPI;
144 }
145 
146 static inline int is_imx53_ecspi(struct spi_imx_data *d)
147 {
148 	return d->devtype_data->devtype == IMX53_ECSPI;
149 }
150 
151 #define MXC_SPI_BUF_RX(type)						\
152 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
153 {									\
154 	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
155 									\
156 	if (spi_imx->rx_buf) {						\
157 		*(type *)spi_imx->rx_buf = val;				\
158 		spi_imx->rx_buf += sizeof(type);			\
159 	}								\
160 									\
161 	spi_imx->remainder -= sizeof(type);				\
162 }
163 
164 #define MXC_SPI_BUF_TX(type)						\
165 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
166 {									\
167 	type val = 0;							\
168 									\
169 	if (spi_imx->tx_buf) {						\
170 		val = *(type *)spi_imx->tx_buf;				\
171 		spi_imx->tx_buf += sizeof(type);			\
172 	}								\
173 									\
174 	spi_imx->count -= sizeof(type);					\
175 									\
176 	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
177 }
178 
179 MXC_SPI_BUF_RX(u8)
180 MXC_SPI_BUF_TX(u8)
181 MXC_SPI_BUF_RX(u16)
182 MXC_SPI_BUF_TX(u16)
183 MXC_SPI_BUF_RX(u32)
184 MXC_SPI_BUF_TX(u32)
185 
186 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
187  * (which is currently not the case in this driver)
188  */
189 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
190 	256, 384, 512, 768, 1024};
191 
192 /* MX21, MX27 */
193 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
194 		unsigned int fspi, unsigned int max, unsigned int *fres)
195 {
196 	int i;
197 
198 	for (i = 2; i < max; i++)
199 		if (fspi * mxc_clkdivs[i] >= fin)
200 			break;
201 
202 	*fres = fin / mxc_clkdivs[i];
203 	return i;
204 }
205 
206 /* MX1, MX31, MX35, MX51 CSPI */
207 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
208 		unsigned int fspi, unsigned int *fres)
209 {
210 	int i, div = 4;
211 
212 	for (i = 0; i < 7; i++) {
213 		if (fspi * div >= fin)
214 			goto out;
215 		div <<= 1;
216 	}
217 
218 out:
219 	*fres = fin / div;
220 	return i;
221 }
222 
223 static int spi_imx_bytes_per_word(const int bits_per_word)
224 {
225 	if (bits_per_word <= 8)
226 		return 1;
227 	else if (bits_per_word <= 16)
228 		return 2;
229 	else
230 		return 4;
231 }
232 
233 static bool spi_imx_can_dma(struct spi_controller *controller, struct spi_device *spi,
234 			 struct spi_transfer *transfer)
235 {
236 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
237 
238 	if (!use_dma || controller->fallback)
239 		return false;
240 
241 	if (!controller->dma_rx)
242 		return false;
243 
244 	if (spi_imx->slave_mode)
245 		return false;
246 
247 	if (transfer->len < spi_imx->devtype_data->fifo_size)
248 		return false;
249 
250 	spi_imx->dynamic_burst = 0;
251 
252 	return true;
253 }
254 
255 /*
256  * Note the number of natively supported chip selects for MX51 is 4. Some
257  * devices may have less actual SS pins but the register map supports 4. When
258  * using gpio chip selects the cs values passed into the macros below can go
259  * outside the range 0 - 3. We therefore need to limit the cs value to avoid
260  * corrupting bits outside the allocated locations.
261  *
262  * The simplest way to do this is to just mask the cs bits to 2 bits. This
263  * still allows all 4 native chip selects to work as well as gpio chip selects
264  * (which can use any of the 4 chip select configurations).
265  */
266 
267 #define MX51_ECSPI_CTRL		0x08
268 #define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
269 #define MX51_ECSPI_CTRL_XCH		(1 <<  2)
270 #define MX51_ECSPI_CTRL_SMC		(1 << 3)
271 #define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
272 #define MX51_ECSPI_CTRL_DRCTL(drctl)	((drctl) << 16)
273 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
274 #define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
275 #define MX51_ECSPI_CTRL_CS(cs)		((cs & 3) << 18)
276 #define MX51_ECSPI_CTRL_BL_OFFSET	20
277 #define MX51_ECSPI_CTRL_BL_MASK		(0xfff << 20)
278 
279 #define MX51_ECSPI_CONFIG	0x0c
280 #define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs & 3) +  0))
281 #define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs & 3) +  4))
282 #define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs & 3) +  8))
283 #define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs & 3) + 12))
284 #define MX51_ECSPI_CONFIG_SCLKCTL(cs)	(1 << ((cs & 3) + 20))
285 
286 #define MX51_ECSPI_INT		0x10
287 #define MX51_ECSPI_INT_TEEN		(1 <<  0)
288 #define MX51_ECSPI_INT_RREN		(1 <<  3)
289 #define MX51_ECSPI_INT_RDREN		(1 <<  4)
290 
291 #define MX51_ECSPI_DMA		0x14
292 #define MX51_ECSPI_DMA_TX_WML(wml)	((wml) & 0x3f)
293 #define MX51_ECSPI_DMA_RX_WML(wml)	(((wml) & 0x3f) << 16)
294 #define MX51_ECSPI_DMA_RXT_WML(wml)	(((wml) & 0x3f) << 24)
295 
296 #define MX51_ECSPI_DMA_TEDEN		(1 << 7)
297 #define MX51_ECSPI_DMA_RXDEN		(1 << 23)
298 #define MX51_ECSPI_DMA_RXTDEN		(1 << 31)
299 
300 #define MX51_ECSPI_STAT		0x18
301 #define MX51_ECSPI_STAT_RR		(1 <<  3)
302 
303 #define MX51_ECSPI_TESTREG	0x20
304 #define MX51_ECSPI_TESTREG_LBC	BIT(31)
305 
306 static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
307 {
308 	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
309 
310 	if (spi_imx->rx_buf) {
311 #ifdef __LITTLE_ENDIAN
312 		unsigned int bytes_per_word;
313 
314 		bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
315 		if (bytes_per_word == 1)
316 			swab32s(&val);
317 		else if (bytes_per_word == 2)
318 			swahw32s(&val);
319 #endif
320 		*(u32 *)spi_imx->rx_buf = val;
321 		spi_imx->rx_buf += sizeof(u32);
322 	}
323 
324 	spi_imx->remainder -= sizeof(u32);
325 }
326 
327 static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
328 {
329 	int unaligned;
330 	u32 val;
331 
332 	unaligned = spi_imx->remainder % 4;
333 
334 	if (!unaligned) {
335 		spi_imx_buf_rx_swap_u32(spi_imx);
336 		return;
337 	}
338 
339 	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
340 		spi_imx_buf_rx_u16(spi_imx);
341 		return;
342 	}
343 
344 	val = readl(spi_imx->base + MXC_CSPIRXDATA);
345 
346 	while (unaligned--) {
347 		if (spi_imx->rx_buf) {
348 			*(u8 *)spi_imx->rx_buf = (val >> (8 * unaligned)) & 0xff;
349 			spi_imx->rx_buf++;
350 		}
351 		spi_imx->remainder--;
352 	}
353 }
354 
355 static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
356 {
357 	u32 val = 0;
358 #ifdef __LITTLE_ENDIAN
359 	unsigned int bytes_per_word;
360 #endif
361 
362 	if (spi_imx->tx_buf) {
363 		val = *(u32 *)spi_imx->tx_buf;
364 		spi_imx->tx_buf += sizeof(u32);
365 	}
366 
367 	spi_imx->count -= sizeof(u32);
368 #ifdef __LITTLE_ENDIAN
369 	bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
370 
371 	if (bytes_per_word == 1)
372 		swab32s(&val);
373 	else if (bytes_per_word == 2)
374 		swahw32s(&val);
375 #endif
376 	writel(val, spi_imx->base + MXC_CSPITXDATA);
377 }
378 
379 static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
380 {
381 	int unaligned;
382 	u32 val = 0;
383 
384 	unaligned = spi_imx->count % 4;
385 
386 	if (!unaligned) {
387 		spi_imx_buf_tx_swap_u32(spi_imx);
388 		return;
389 	}
390 
391 	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
392 		spi_imx_buf_tx_u16(spi_imx);
393 		return;
394 	}
395 
396 	while (unaligned--) {
397 		if (spi_imx->tx_buf) {
398 			val |= *(u8 *)spi_imx->tx_buf << (8 * unaligned);
399 			spi_imx->tx_buf++;
400 		}
401 		spi_imx->count--;
402 	}
403 
404 	writel(val, spi_imx->base + MXC_CSPITXDATA);
405 }
406 
407 static void mx53_ecspi_rx_slave(struct spi_imx_data *spi_imx)
408 {
409 	u32 val = be32_to_cpu(readl(spi_imx->base + MXC_CSPIRXDATA));
410 
411 	if (spi_imx->rx_buf) {
412 		int n_bytes = spi_imx->slave_burst % sizeof(val);
413 
414 		if (!n_bytes)
415 			n_bytes = sizeof(val);
416 
417 		memcpy(spi_imx->rx_buf,
418 		       ((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
419 
420 		spi_imx->rx_buf += n_bytes;
421 		spi_imx->slave_burst -= n_bytes;
422 	}
423 
424 	spi_imx->remainder -= sizeof(u32);
425 }
426 
427 static void mx53_ecspi_tx_slave(struct spi_imx_data *spi_imx)
428 {
429 	u32 val = 0;
430 	int n_bytes = spi_imx->count % sizeof(val);
431 
432 	if (!n_bytes)
433 		n_bytes = sizeof(val);
434 
435 	if (spi_imx->tx_buf) {
436 		memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
437 		       spi_imx->tx_buf, n_bytes);
438 		val = cpu_to_be32(val);
439 		spi_imx->tx_buf += n_bytes;
440 	}
441 
442 	spi_imx->count -= n_bytes;
443 
444 	writel(val, spi_imx->base + MXC_CSPITXDATA);
445 }
446 
447 /* MX51 eCSPI */
448 static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
449 				      unsigned int fspi, unsigned int *fres)
450 {
451 	/*
452 	 * there are two 4-bit dividers, the pre-divider divides by
453 	 * $pre, the post-divider by 2^$post
454 	 */
455 	unsigned int pre, post;
456 	unsigned int fin = spi_imx->spi_clk;
457 
458 	fspi = min(fspi, fin);
459 
460 	post = fls(fin) - fls(fspi);
461 	if (fin > fspi << post)
462 		post++;
463 
464 	/* now we have: (fin <= fspi << post) with post being minimal */
465 
466 	post = max(4U, post) - 4;
467 	if (unlikely(post > 0xf)) {
468 		dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
469 				fspi, fin);
470 		return 0xff;
471 	}
472 
473 	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
474 
475 	dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
476 			__func__, fin, fspi, post, pre);
477 
478 	/* Resulting frequency for the SCLK line. */
479 	*fres = (fin / (pre + 1)) >> post;
480 
481 	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
482 		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
483 }
484 
485 static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
486 {
487 	unsigned int val = 0;
488 
489 	if (enable & MXC_INT_TE)
490 		val |= MX51_ECSPI_INT_TEEN;
491 
492 	if (enable & MXC_INT_RR)
493 		val |= MX51_ECSPI_INT_RREN;
494 
495 	if (enable & MXC_INT_RDR)
496 		val |= MX51_ECSPI_INT_RDREN;
497 
498 	writel(val, spi_imx->base + MX51_ECSPI_INT);
499 }
500 
501 static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
502 {
503 	u32 reg;
504 
505 	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
506 	reg |= MX51_ECSPI_CTRL_XCH;
507 	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
508 }
509 
510 static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
511 {
512 	u32 ctrl;
513 
514 	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
515 	ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
516 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
517 }
518 
519 static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
520 				      struct spi_message *msg)
521 {
522 	struct spi_device *spi = msg->spi;
523 	struct spi_transfer *xfer;
524 	u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
525 	u32 min_speed_hz = ~0U;
526 	u32 testreg, delay;
527 	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
528 	u32 current_cfg = cfg;
529 
530 	/* set Master or Slave mode */
531 	if (spi_imx->slave_mode)
532 		ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
533 	else
534 		ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
535 
536 	/*
537 	 * Enable SPI_RDY handling (falling edge/level triggered).
538 	 */
539 	if (spi->mode & SPI_READY)
540 		ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
541 
542 	/* set chip select to use */
543 	ctrl |= MX51_ECSPI_CTRL_CS(spi_get_chipselect(spi, 0));
544 
545 	/*
546 	 * The ctrl register must be written first, with the EN bit set other
547 	 * registers must not be written to.
548 	 */
549 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
550 
551 	testreg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
552 	if (spi->mode & SPI_LOOP)
553 		testreg |= MX51_ECSPI_TESTREG_LBC;
554 	else
555 		testreg &= ~MX51_ECSPI_TESTREG_LBC;
556 	writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
557 
558 	/*
559 	 * eCSPI burst completion by Chip Select signal in Slave mode
560 	 * is not functional for imx53 Soc, config SPI burst completed when
561 	 * BURST_LENGTH + 1 bits are received
562 	 */
563 	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
564 		cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(spi_get_chipselect(spi, 0));
565 	else
566 		cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi_get_chipselect(spi, 0));
567 
568 	if (spi->mode & SPI_CPOL) {
569 		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi_get_chipselect(spi, 0));
570 		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi_get_chipselect(spi, 0));
571 	} else {
572 		cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi_get_chipselect(spi, 0));
573 		cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi_get_chipselect(spi, 0));
574 	}
575 
576 	if (spi->mode & SPI_CS_HIGH)
577 		cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi_get_chipselect(spi, 0));
578 	else
579 		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi_get_chipselect(spi, 0));
580 
581 	if (cfg == current_cfg)
582 		return 0;
583 
584 	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
585 
586 	/*
587 	 * Wait until the changes in the configuration register CONFIGREG
588 	 * propagate into the hardware. It takes exactly one tick of the
589 	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
590 	 * effect of the delay it takes for the hardware to apply changes
591 	 * is noticable if the SCLK clock run very slow. In such a case, if
592 	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
593 	 * be asserted before the SCLK polarity changes, which would disrupt
594 	 * the SPI communication as the device on the other end would consider
595 	 * the change of SCLK polarity as a clock tick already.
596 	 *
597 	 * Because spi_imx->spi_bus_clk is only set in prepare_message
598 	 * callback, iterate over all the transfers in spi_message, find the
599 	 * one with lowest bus frequency, and use that bus frequency for the
600 	 * delay calculation. In case all transfers have speed_hz == 0, then
601 	 * min_speed_hz is ~0 and the resulting delay is zero.
602 	 */
603 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
604 		if (!xfer->speed_hz)
605 			continue;
606 		min_speed_hz = min(xfer->speed_hz, min_speed_hz);
607 	}
608 
609 	delay = (2 * 1000000) / min_speed_hz;
610 	if (likely(delay < 10))	/* SCLK is faster than 200 kHz */
611 		udelay(delay);
612 	else			/* SCLK is _very_ slow */
613 		usleep_range(delay, delay + 10);
614 
615 	return 0;
616 }
617 
618 static void mx51_configure_cpha(struct spi_imx_data *spi_imx,
619 				struct spi_device *spi)
620 {
621 	bool cpha = (spi->mode & SPI_CPHA);
622 	bool flip_cpha = (spi->mode & SPI_RX_CPHA_FLIP) && spi_imx->rx_only;
623 	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
624 
625 	/* Flip cpha logical value iff flip_cpha */
626 	cpha ^= flip_cpha;
627 
628 	if (cpha)
629 		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi_get_chipselect(spi, 0));
630 	else
631 		cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi_get_chipselect(spi, 0));
632 
633 	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
634 }
635 
636 static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
637 				       struct spi_device *spi)
638 {
639 	u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
640 	u32 clk;
641 
642 	/* Clear BL field and set the right value */
643 	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
644 	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
645 		ctrl |= (spi_imx->slave_burst * 8 - 1)
646 			<< MX51_ECSPI_CTRL_BL_OFFSET;
647 	else
648 		ctrl |= (spi_imx->bits_per_word - 1)
649 			<< MX51_ECSPI_CTRL_BL_OFFSET;
650 
651 	/* set clock speed */
652 	ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
653 		  0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
654 	ctrl |= mx51_ecspi_clkdiv(spi_imx, spi_imx->spi_bus_clk, &clk);
655 	spi_imx->spi_bus_clk = clk;
656 
657 	mx51_configure_cpha(spi_imx, spi);
658 
659 	/*
660 	 * ERR009165: work in XHC mode instead of SMC as PIO on the chips
661 	 * before i.mx6ul.
662 	 */
663 	if (spi_imx->usedma && spi_imx->devtype_data->tx_glitch_fixed)
664 		ctrl |= MX51_ECSPI_CTRL_SMC;
665 	else
666 		ctrl &= ~MX51_ECSPI_CTRL_SMC;
667 
668 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
669 
670 	return 0;
671 }
672 
673 static void mx51_setup_wml(struct spi_imx_data *spi_imx)
674 {
675 	u32 tx_wml = 0;
676 
677 	if (spi_imx->devtype_data->tx_glitch_fixed)
678 		tx_wml = spi_imx->wml;
679 	/*
680 	 * Configure the DMA register: setup the watermark
681 	 * and enable DMA request.
682 	 */
683 	writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) |
684 		MX51_ECSPI_DMA_TX_WML(tx_wml) |
685 		MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
686 		MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
687 		MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
688 }
689 
690 static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
691 {
692 	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
693 }
694 
695 static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
696 {
697 	/* drain receive buffer */
698 	while (mx51_ecspi_rx_available(spi_imx))
699 		readl(spi_imx->base + MXC_CSPIRXDATA);
700 }
701 
702 #define MX31_INTREG_TEEN	(1 << 0)
703 #define MX31_INTREG_RREN	(1 << 3)
704 
705 #define MX31_CSPICTRL_ENABLE	(1 << 0)
706 #define MX31_CSPICTRL_MASTER	(1 << 1)
707 #define MX31_CSPICTRL_XCH	(1 << 2)
708 #define MX31_CSPICTRL_SMC	(1 << 3)
709 #define MX31_CSPICTRL_POL	(1 << 4)
710 #define MX31_CSPICTRL_PHA	(1 << 5)
711 #define MX31_CSPICTRL_SSCTL	(1 << 6)
712 #define MX31_CSPICTRL_SSPOL	(1 << 7)
713 #define MX31_CSPICTRL_BC_SHIFT	8
714 #define MX35_CSPICTRL_BL_SHIFT	20
715 #define MX31_CSPICTRL_CS_SHIFT	24
716 #define MX35_CSPICTRL_CS_SHIFT	12
717 #define MX31_CSPICTRL_DR_SHIFT	16
718 
719 #define MX31_CSPI_DMAREG	0x10
720 #define MX31_DMAREG_RH_DEN	(1<<4)
721 #define MX31_DMAREG_TH_DEN	(1<<1)
722 
723 #define MX31_CSPISTATUS		0x14
724 #define MX31_STATUS_RR		(1 << 3)
725 
726 #define MX31_CSPI_TESTREG	0x1C
727 #define MX31_TEST_LBC		(1 << 14)
728 
729 /* These functions also work for the i.MX35, but be aware that
730  * the i.MX35 has a slightly different register layout for bits
731  * we do not use here.
732  */
733 static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
734 {
735 	unsigned int val = 0;
736 
737 	if (enable & MXC_INT_TE)
738 		val |= MX31_INTREG_TEEN;
739 	if (enable & MXC_INT_RR)
740 		val |= MX31_INTREG_RREN;
741 
742 	writel(val, spi_imx->base + MXC_CSPIINT);
743 }
744 
745 static void mx31_trigger(struct spi_imx_data *spi_imx)
746 {
747 	unsigned int reg;
748 
749 	reg = readl(spi_imx->base + MXC_CSPICTRL);
750 	reg |= MX31_CSPICTRL_XCH;
751 	writel(reg, spi_imx->base + MXC_CSPICTRL);
752 }
753 
754 static int mx31_prepare_message(struct spi_imx_data *spi_imx,
755 				struct spi_message *msg)
756 {
757 	return 0;
758 }
759 
760 static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
761 				 struct spi_device *spi)
762 {
763 	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
764 	unsigned int clk;
765 
766 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
767 		MX31_CSPICTRL_DR_SHIFT;
768 	spi_imx->spi_bus_clk = clk;
769 
770 	if (is_imx35_cspi(spi_imx)) {
771 		reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
772 		reg |= MX31_CSPICTRL_SSCTL;
773 	} else {
774 		reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
775 	}
776 
777 	if (spi->mode & SPI_CPHA)
778 		reg |= MX31_CSPICTRL_PHA;
779 	if (spi->mode & SPI_CPOL)
780 		reg |= MX31_CSPICTRL_POL;
781 	if (spi->mode & SPI_CS_HIGH)
782 		reg |= MX31_CSPICTRL_SSPOL;
783 	if (!spi_get_csgpiod(spi, 0))
784 		reg |= (spi_get_chipselect(spi, 0)) <<
785 			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
786 						  MX31_CSPICTRL_CS_SHIFT);
787 
788 	if (spi_imx->usedma)
789 		reg |= MX31_CSPICTRL_SMC;
790 
791 	writel(reg, spi_imx->base + MXC_CSPICTRL);
792 
793 	reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
794 	if (spi->mode & SPI_LOOP)
795 		reg |= MX31_TEST_LBC;
796 	else
797 		reg &= ~MX31_TEST_LBC;
798 	writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
799 
800 	if (spi_imx->usedma) {
801 		/*
802 		 * configure DMA requests when RXFIFO is half full and
803 		 * when TXFIFO is half empty
804 		 */
805 		writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
806 			spi_imx->base + MX31_CSPI_DMAREG);
807 	}
808 
809 	return 0;
810 }
811 
812 static int mx31_rx_available(struct spi_imx_data *spi_imx)
813 {
814 	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
815 }
816 
817 static void mx31_reset(struct spi_imx_data *spi_imx)
818 {
819 	/* drain receive buffer */
820 	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
821 		readl(spi_imx->base + MXC_CSPIRXDATA);
822 }
823 
824 #define MX21_INTREG_RR		(1 << 4)
825 #define MX21_INTREG_TEEN	(1 << 9)
826 #define MX21_INTREG_RREN	(1 << 13)
827 
828 #define MX21_CSPICTRL_POL	(1 << 5)
829 #define MX21_CSPICTRL_PHA	(1 << 6)
830 #define MX21_CSPICTRL_SSPOL	(1 << 8)
831 #define MX21_CSPICTRL_XCH	(1 << 9)
832 #define MX21_CSPICTRL_ENABLE	(1 << 10)
833 #define MX21_CSPICTRL_MASTER	(1 << 11)
834 #define MX21_CSPICTRL_DR_SHIFT	14
835 #define MX21_CSPICTRL_CS_SHIFT	19
836 
837 static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
838 {
839 	unsigned int val = 0;
840 
841 	if (enable & MXC_INT_TE)
842 		val |= MX21_INTREG_TEEN;
843 	if (enable & MXC_INT_RR)
844 		val |= MX21_INTREG_RREN;
845 
846 	writel(val, spi_imx->base + MXC_CSPIINT);
847 }
848 
849 static void mx21_trigger(struct spi_imx_data *spi_imx)
850 {
851 	unsigned int reg;
852 
853 	reg = readl(spi_imx->base + MXC_CSPICTRL);
854 	reg |= MX21_CSPICTRL_XCH;
855 	writel(reg, spi_imx->base + MXC_CSPICTRL);
856 }
857 
858 static int mx21_prepare_message(struct spi_imx_data *spi_imx,
859 				struct spi_message *msg)
860 {
861 	return 0;
862 }
863 
864 static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
865 				 struct spi_device *spi)
866 {
867 	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
868 	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
869 	unsigned int clk;
870 
871 	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, spi_imx->spi_bus_clk, max, &clk)
872 		<< MX21_CSPICTRL_DR_SHIFT;
873 	spi_imx->spi_bus_clk = clk;
874 
875 	reg |= spi_imx->bits_per_word - 1;
876 
877 	if (spi->mode & SPI_CPHA)
878 		reg |= MX21_CSPICTRL_PHA;
879 	if (spi->mode & SPI_CPOL)
880 		reg |= MX21_CSPICTRL_POL;
881 	if (spi->mode & SPI_CS_HIGH)
882 		reg |= MX21_CSPICTRL_SSPOL;
883 	if (!spi_get_csgpiod(spi, 0))
884 		reg |= spi_get_chipselect(spi, 0) << MX21_CSPICTRL_CS_SHIFT;
885 
886 	writel(reg, spi_imx->base + MXC_CSPICTRL);
887 
888 	return 0;
889 }
890 
891 static int mx21_rx_available(struct spi_imx_data *spi_imx)
892 {
893 	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
894 }
895 
896 static void mx21_reset(struct spi_imx_data *spi_imx)
897 {
898 	writel(1, spi_imx->base + MXC_RESET);
899 }
900 
901 #define MX1_INTREG_RR		(1 << 3)
902 #define MX1_INTREG_TEEN		(1 << 8)
903 #define MX1_INTREG_RREN		(1 << 11)
904 
905 #define MX1_CSPICTRL_POL	(1 << 4)
906 #define MX1_CSPICTRL_PHA	(1 << 5)
907 #define MX1_CSPICTRL_XCH	(1 << 8)
908 #define MX1_CSPICTRL_ENABLE	(1 << 9)
909 #define MX1_CSPICTRL_MASTER	(1 << 10)
910 #define MX1_CSPICTRL_DR_SHIFT	13
911 
912 static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
913 {
914 	unsigned int val = 0;
915 
916 	if (enable & MXC_INT_TE)
917 		val |= MX1_INTREG_TEEN;
918 	if (enable & MXC_INT_RR)
919 		val |= MX1_INTREG_RREN;
920 
921 	writel(val, spi_imx->base + MXC_CSPIINT);
922 }
923 
924 static void mx1_trigger(struct spi_imx_data *spi_imx)
925 {
926 	unsigned int reg;
927 
928 	reg = readl(spi_imx->base + MXC_CSPICTRL);
929 	reg |= MX1_CSPICTRL_XCH;
930 	writel(reg, spi_imx->base + MXC_CSPICTRL);
931 }
932 
933 static int mx1_prepare_message(struct spi_imx_data *spi_imx,
934 			       struct spi_message *msg)
935 {
936 	return 0;
937 }
938 
939 static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
940 				struct spi_device *spi)
941 {
942 	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
943 	unsigned int clk;
944 
945 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
946 		MX1_CSPICTRL_DR_SHIFT;
947 	spi_imx->spi_bus_clk = clk;
948 
949 	reg |= spi_imx->bits_per_word - 1;
950 
951 	if (spi->mode & SPI_CPHA)
952 		reg |= MX1_CSPICTRL_PHA;
953 	if (spi->mode & SPI_CPOL)
954 		reg |= MX1_CSPICTRL_POL;
955 
956 	writel(reg, spi_imx->base + MXC_CSPICTRL);
957 
958 	return 0;
959 }
960 
961 static int mx1_rx_available(struct spi_imx_data *spi_imx)
962 {
963 	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
964 }
965 
966 static void mx1_reset(struct spi_imx_data *spi_imx)
967 {
968 	writel(1, spi_imx->base + MXC_RESET);
969 }
970 
971 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
972 	.intctrl = mx1_intctrl,
973 	.prepare_message = mx1_prepare_message,
974 	.prepare_transfer = mx1_prepare_transfer,
975 	.trigger = mx1_trigger,
976 	.rx_available = mx1_rx_available,
977 	.reset = mx1_reset,
978 	.fifo_size = 8,
979 	.has_dmamode = false,
980 	.dynamic_burst = false,
981 	.has_slavemode = false,
982 	.devtype = IMX1_CSPI,
983 };
984 
985 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
986 	.intctrl = mx21_intctrl,
987 	.prepare_message = mx21_prepare_message,
988 	.prepare_transfer = mx21_prepare_transfer,
989 	.trigger = mx21_trigger,
990 	.rx_available = mx21_rx_available,
991 	.reset = mx21_reset,
992 	.fifo_size = 8,
993 	.has_dmamode = false,
994 	.dynamic_burst = false,
995 	.has_slavemode = false,
996 	.devtype = IMX21_CSPI,
997 };
998 
999 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
1000 	/* i.mx27 cspi shares the functions with i.mx21 one */
1001 	.intctrl = mx21_intctrl,
1002 	.prepare_message = mx21_prepare_message,
1003 	.prepare_transfer = mx21_prepare_transfer,
1004 	.trigger = mx21_trigger,
1005 	.rx_available = mx21_rx_available,
1006 	.reset = mx21_reset,
1007 	.fifo_size = 8,
1008 	.has_dmamode = false,
1009 	.dynamic_burst = false,
1010 	.has_slavemode = false,
1011 	.devtype = IMX27_CSPI,
1012 };
1013 
1014 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
1015 	.intctrl = mx31_intctrl,
1016 	.prepare_message = mx31_prepare_message,
1017 	.prepare_transfer = mx31_prepare_transfer,
1018 	.trigger = mx31_trigger,
1019 	.rx_available = mx31_rx_available,
1020 	.reset = mx31_reset,
1021 	.fifo_size = 8,
1022 	.has_dmamode = false,
1023 	.dynamic_burst = false,
1024 	.has_slavemode = false,
1025 	.devtype = IMX31_CSPI,
1026 };
1027 
1028 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
1029 	/* i.mx35 and later cspi shares the functions with i.mx31 one */
1030 	.intctrl = mx31_intctrl,
1031 	.prepare_message = mx31_prepare_message,
1032 	.prepare_transfer = mx31_prepare_transfer,
1033 	.trigger = mx31_trigger,
1034 	.rx_available = mx31_rx_available,
1035 	.reset = mx31_reset,
1036 	.fifo_size = 8,
1037 	.has_dmamode = true,
1038 	.dynamic_burst = false,
1039 	.has_slavemode = false,
1040 	.devtype = IMX35_CSPI,
1041 };
1042 
1043 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
1044 	.intctrl = mx51_ecspi_intctrl,
1045 	.prepare_message = mx51_ecspi_prepare_message,
1046 	.prepare_transfer = mx51_ecspi_prepare_transfer,
1047 	.trigger = mx51_ecspi_trigger,
1048 	.rx_available = mx51_ecspi_rx_available,
1049 	.reset = mx51_ecspi_reset,
1050 	.setup_wml = mx51_setup_wml,
1051 	.fifo_size = 64,
1052 	.has_dmamode = true,
1053 	.dynamic_burst = true,
1054 	.has_slavemode = true,
1055 	.disable = mx51_ecspi_disable,
1056 	.devtype = IMX51_ECSPI,
1057 };
1058 
1059 static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
1060 	.intctrl = mx51_ecspi_intctrl,
1061 	.prepare_message = mx51_ecspi_prepare_message,
1062 	.prepare_transfer = mx51_ecspi_prepare_transfer,
1063 	.trigger = mx51_ecspi_trigger,
1064 	.rx_available = mx51_ecspi_rx_available,
1065 	.reset = mx51_ecspi_reset,
1066 	.fifo_size = 64,
1067 	.has_dmamode = true,
1068 	.has_slavemode = true,
1069 	.disable = mx51_ecspi_disable,
1070 	.devtype = IMX53_ECSPI,
1071 };
1072 
1073 static struct spi_imx_devtype_data imx6ul_ecspi_devtype_data = {
1074 	.intctrl = mx51_ecspi_intctrl,
1075 	.prepare_message = mx51_ecspi_prepare_message,
1076 	.prepare_transfer = mx51_ecspi_prepare_transfer,
1077 	.trigger = mx51_ecspi_trigger,
1078 	.rx_available = mx51_ecspi_rx_available,
1079 	.reset = mx51_ecspi_reset,
1080 	.setup_wml = mx51_setup_wml,
1081 	.fifo_size = 64,
1082 	.has_dmamode = true,
1083 	.dynamic_burst = true,
1084 	.has_slavemode = true,
1085 	.tx_glitch_fixed = true,
1086 	.disable = mx51_ecspi_disable,
1087 	.devtype = IMX51_ECSPI,
1088 };
1089 
1090 static const struct of_device_id spi_imx_dt_ids[] = {
1091 	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
1092 	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
1093 	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
1094 	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
1095 	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
1096 	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
1097 	{ .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
1098 	{ .compatible = "fsl,imx6ul-ecspi", .data = &imx6ul_ecspi_devtype_data, },
1099 	{ /* sentinel */ }
1100 };
1101 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
1102 
1103 static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
1104 {
1105 	u32 ctrl;
1106 
1107 	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
1108 	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
1109 	ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
1110 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
1111 }
1112 
1113 static void spi_imx_push(struct spi_imx_data *spi_imx)
1114 {
1115 	unsigned int burst_len;
1116 
1117 	/*
1118 	 * Reload the FIFO when the remaining bytes to be transferred in the
1119 	 * current burst is 0. This only applies when bits_per_word is a
1120 	 * multiple of 8.
1121 	 */
1122 	if (!spi_imx->remainder) {
1123 		if (spi_imx->dynamic_burst) {
1124 
1125 			/* We need to deal unaligned data first */
1126 			burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
1127 
1128 			if (!burst_len)
1129 				burst_len = MX51_ECSPI_CTRL_MAX_BURST;
1130 
1131 			spi_imx_set_burst_len(spi_imx, burst_len * 8);
1132 
1133 			spi_imx->remainder = burst_len;
1134 		} else {
1135 			spi_imx->remainder = spi_imx_bytes_per_word(spi_imx->bits_per_word);
1136 		}
1137 	}
1138 
1139 	while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
1140 		if (!spi_imx->count)
1141 			break;
1142 		if (spi_imx->dynamic_burst &&
1143 		    spi_imx->txfifo >= DIV_ROUND_UP(spi_imx->remainder, 4))
1144 			break;
1145 		spi_imx->tx(spi_imx);
1146 		spi_imx->txfifo++;
1147 	}
1148 
1149 	if (!spi_imx->slave_mode)
1150 		spi_imx->devtype_data->trigger(spi_imx);
1151 }
1152 
1153 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
1154 {
1155 	struct spi_imx_data *spi_imx = dev_id;
1156 
1157 	while (spi_imx->txfifo &&
1158 	       spi_imx->devtype_data->rx_available(spi_imx)) {
1159 		spi_imx->rx(spi_imx);
1160 		spi_imx->txfifo--;
1161 	}
1162 
1163 	if (spi_imx->count) {
1164 		spi_imx_push(spi_imx);
1165 		return IRQ_HANDLED;
1166 	}
1167 
1168 	if (spi_imx->txfifo) {
1169 		/* No data left to push, but still waiting for rx data,
1170 		 * enable receive data available interrupt.
1171 		 */
1172 		spi_imx->devtype_data->intctrl(
1173 				spi_imx, MXC_INT_RR);
1174 		return IRQ_HANDLED;
1175 	}
1176 
1177 	spi_imx->devtype_data->intctrl(spi_imx, 0);
1178 	complete(&spi_imx->xfer_done);
1179 
1180 	return IRQ_HANDLED;
1181 }
1182 
1183 static int spi_imx_dma_configure(struct spi_controller *controller)
1184 {
1185 	int ret;
1186 	enum dma_slave_buswidth buswidth;
1187 	struct dma_slave_config rx = {}, tx = {};
1188 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1189 
1190 	switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
1191 	case 4:
1192 		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
1193 		break;
1194 	case 2:
1195 		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
1196 		break;
1197 	case 1:
1198 		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
1199 		break;
1200 	default:
1201 		return -EINVAL;
1202 	}
1203 
1204 	tx.direction = DMA_MEM_TO_DEV;
1205 	tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
1206 	tx.dst_addr_width = buswidth;
1207 	tx.dst_maxburst = spi_imx->wml;
1208 	ret = dmaengine_slave_config(controller->dma_tx, &tx);
1209 	if (ret) {
1210 		dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
1211 		return ret;
1212 	}
1213 
1214 	rx.direction = DMA_DEV_TO_MEM;
1215 	rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
1216 	rx.src_addr_width = buswidth;
1217 	rx.src_maxburst = spi_imx->wml;
1218 	ret = dmaengine_slave_config(controller->dma_rx, &rx);
1219 	if (ret) {
1220 		dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
1221 		return ret;
1222 	}
1223 
1224 	return 0;
1225 }
1226 
1227 static int spi_imx_setupxfer(struct spi_device *spi,
1228 				 struct spi_transfer *t)
1229 {
1230 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1231 
1232 	if (!t)
1233 		return 0;
1234 
1235 	if (!t->speed_hz) {
1236 		if (!spi->max_speed_hz) {
1237 			dev_err(&spi->dev, "no speed_hz provided!\n");
1238 			return -EINVAL;
1239 		}
1240 		dev_dbg(&spi->dev, "using spi->max_speed_hz!\n");
1241 		spi_imx->spi_bus_clk = spi->max_speed_hz;
1242 	} else
1243 		spi_imx->spi_bus_clk = t->speed_hz;
1244 
1245 	spi_imx->bits_per_word = t->bits_per_word;
1246 
1247 	/*
1248 	 * Initialize the functions for transfer. To transfer non byte-aligned
1249 	 * words, we have to use multiple word-size bursts, we can't use
1250 	 * dynamic_burst in that case.
1251 	 */
1252 	if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode &&
1253 	    !(spi->mode & SPI_CS_WORD) &&
1254 	    (spi_imx->bits_per_word == 8 ||
1255 	    spi_imx->bits_per_word == 16 ||
1256 	    spi_imx->bits_per_word == 32)) {
1257 
1258 		spi_imx->rx = spi_imx_buf_rx_swap;
1259 		spi_imx->tx = spi_imx_buf_tx_swap;
1260 		spi_imx->dynamic_burst = 1;
1261 
1262 	} else {
1263 		if (spi_imx->bits_per_word <= 8) {
1264 			spi_imx->rx = spi_imx_buf_rx_u8;
1265 			spi_imx->tx = spi_imx_buf_tx_u8;
1266 		} else if (spi_imx->bits_per_word <= 16) {
1267 			spi_imx->rx = spi_imx_buf_rx_u16;
1268 			spi_imx->tx = spi_imx_buf_tx_u16;
1269 		} else {
1270 			spi_imx->rx = spi_imx_buf_rx_u32;
1271 			spi_imx->tx = spi_imx_buf_tx_u32;
1272 		}
1273 		spi_imx->dynamic_burst = 0;
1274 	}
1275 
1276 	if (spi_imx_can_dma(spi_imx->controller, spi, t))
1277 		spi_imx->usedma = true;
1278 	else
1279 		spi_imx->usedma = false;
1280 
1281 	spi_imx->rx_only = ((t->tx_buf == NULL)
1282 			|| (t->tx_buf == spi->controller->dummy_tx));
1283 
1284 	if (is_imx53_ecspi(spi_imx) && spi_imx->slave_mode) {
1285 		spi_imx->rx = mx53_ecspi_rx_slave;
1286 		spi_imx->tx = mx53_ecspi_tx_slave;
1287 		spi_imx->slave_burst = t->len;
1288 	}
1289 
1290 	spi_imx->devtype_data->prepare_transfer(spi_imx, spi);
1291 
1292 	return 0;
1293 }
1294 
1295 static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
1296 {
1297 	struct spi_controller *controller = spi_imx->controller;
1298 
1299 	if (controller->dma_rx) {
1300 		dma_release_channel(controller->dma_rx);
1301 		controller->dma_rx = NULL;
1302 	}
1303 
1304 	if (controller->dma_tx) {
1305 		dma_release_channel(controller->dma_tx);
1306 		controller->dma_tx = NULL;
1307 	}
1308 }
1309 
1310 static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
1311 			     struct spi_controller *controller)
1312 {
1313 	int ret;
1314 
1315 	spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
1316 
1317 	/* Prepare for TX DMA: */
1318 	controller->dma_tx = dma_request_chan(dev, "tx");
1319 	if (IS_ERR(controller->dma_tx)) {
1320 		ret = PTR_ERR(controller->dma_tx);
1321 		dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
1322 		controller->dma_tx = NULL;
1323 		goto err;
1324 	}
1325 
1326 	/* Prepare for RX : */
1327 	controller->dma_rx = dma_request_chan(dev, "rx");
1328 	if (IS_ERR(controller->dma_rx)) {
1329 		ret = PTR_ERR(controller->dma_rx);
1330 		dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
1331 		controller->dma_rx = NULL;
1332 		goto err;
1333 	}
1334 
1335 	init_completion(&spi_imx->dma_rx_completion);
1336 	init_completion(&spi_imx->dma_tx_completion);
1337 	controller->can_dma = spi_imx_can_dma;
1338 	controller->max_dma_len = MAX_SDMA_BD_BYTES;
1339 	spi_imx->controller->flags = SPI_CONTROLLER_MUST_RX |
1340 					 SPI_CONTROLLER_MUST_TX;
1341 
1342 	return 0;
1343 err:
1344 	spi_imx_sdma_exit(spi_imx);
1345 	return ret;
1346 }
1347 
1348 static void spi_imx_dma_rx_callback(void *cookie)
1349 {
1350 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1351 
1352 	complete(&spi_imx->dma_rx_completion);
1353 }
1354 
1355 static void spi_imx_dma_tx_callback(void *cookie)
1356 {
1357 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1358 
1359 	complete(&spi_imx->dma_tx_completion);
1360 }
1361 
1362 static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1363 {
1364 	unsigned long timeout = 0;
1365 
1366 	/* Time with actual data transfer and CS change delay related to HW */
1367 	timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1368 
1369 	/* Add extra second for scheduler related activities */
1370 	timeout += 1;
1371 
1372 	/* Double calculated timeout */
1373 	return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1374 }
1375 
1376 static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1377 				struct spi_transfer *transfer)
1378 {
1379 	struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1380 	unsigned long transfer_timeout;
1381 	unsigned long timeout;
1382 	struct spi_controller *controller = spi_imx->controller;
1383 	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1384 	struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
1385 	unsigned int bytes_per_word, i;
1386 	int ret;
1387 
1388 	/* Get the right burst length from the last sg to ensure no tail data */
1389 	bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
1390 	for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
1391 		if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
1392 			break;
1393 	}
1394 	/* Use 1 as wml in case no available burst length got */
1395 	if (i == 0)
1396 		i = 1;
1397 
1398 	spi_imx->wml =  i;
1399 
1400 	ret = spi_imx_dma_configure(controller);
1401 	if (ret)
1402 		goto dma_failure_no_start;
1403 
1404 	if (!spi_imx->devtype_data->setup_wml) {
1405 		dev_err(spi_imx->dev, "No setup_wml()?\n");
1406 		ret = -EINVAL;
1407 		goto dma_failure_no_start;
1408 	}
1409 	spi_imx->devtype_data->setup_wml(spi_imx);
1410 
1411 	/*
1412 	 * The TX DMA setup starts the transfer, so make sure RX is configured
1413 	 * before TX.
1414 	 */
1415 	desc_rx = dmaengine_prep_slave_sg(controller->dma_rx,
1416 				rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1417 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1418 	if (!desc_rx) {
1419 		ret = -EINVAL;
1420 		goto dma_failure_no_start;
1421 	}
1422 
1423 	desc_rx->callback = spi_imx_dma_rx_callback;
1424 	desc_rx->callback_param = (void *)spi_imx;
1425 	dmaengine_submit(desc_rx);
1426 	reinit_completion(&spi_imx->dma_rx_completion);
1427 	dma_async_issue_pending(controller->dma_rx);
1428 
1429 	desc_tx = dmaengine_prep_slave_sg(controller->dma_tx,
1430 				tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1431 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1432 	if (!desc_tx) {
1433 		dmaengine_terminate_all(controller->dma_tx);
1434 		dmaengine_terminate_all(controller->dma_rx);
1435 		return -EINVAL;
1436 	}
1437 
1438 	desc_tx->callback = spi_imx_dma_tx_callback;
1439 	desc_tx->callback_param = (void *)spi_imx;
1440 	dmaengine_submit(desc_tx);
1441 	reinit_completion(&spi_imx->dma_tx_completion);
1442 	dma_async_issue_pending(controller->dma_tx);
1443 
1444 	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1445 
1446 	/* Wait SDMA to finish the data transfer.*/
1447 	timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1448 						transfer_timeout);
1449 	if (!timeout) {
1450 		dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1451 		dmaengine_terminate_all(controller->dma_tx);
1452 		dmaengine_terminate_all(controller->dma_rx);
1453 		return -ETIMEDOUT;
1454 	}
1455 
1456 	timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1457 					      transfer_timeout);
1458 	if (!timeout) {
1459 		dev_err(&controller->dev, "I/O Error in DMA RX\n");
1460 		spi_imx->devtype_data->reset(spi_imx);
1461 		dmaengine_terminate_all(controller->dma_rx);
1462 		return -ETIMEDOUT;
1463 	}
1464 
1465 	return 0;
1466 /* fallback to pio */
1467 dma_failure_no_start:
1468 	transfer->error |= SPI_TRANS_FAIL_NO_START;
1469 	return ret;
1470 }
1471 
1472 static int spi_imx_pio_transfer(struct spi_device *spi,
1473 				struct spi_transfer *transfer)
1474 {
1475 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1476 	unsigned long transfer_timeout;
1477 	unsigned long timeout;
1478 
1479 	spi_imx->tx_buf = transfer->tx_buf;
1480 	spi_imx->rx_buf = transfer->rx_buf;
1481 	spi_imx->count = transfer->len;
1482 	spi_imx->txfifo = 0;
1483 	spi_imx->remainder = 0;
1484 
1485 	reinit_completion(&spi_imx->xfer_done);
1486 
1487 	spi_imx_push(spi_imx);
1488 
1489 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1490 
1491 	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1492 
1493 	timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
1494 					      transfer_timeout);
1495 	if (!timeout) {
1496 		dev_err(&spi->dev, "I/O Error in PIO\n");
1497 		spi_imx->devtype_data->reset(spi_imx);
1498 		return -ETIMEDOUT;
1499 	}
1500 
1501 	return 0;
1502 }
1503 
1504 static int spi_imx_poll_transfer(struct spi_device *spi,
1505 				 struct spi_transfer *transfer)
1506 {
1507 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1508 	unsigned long timeout;
1509 
1510 	spi_imx->tx_buf = transfer->tx_buf;
1511 	spi_imx->rx_buf = transfer->rx_buf;
1512 	spi_imx->count = transfer->len;
1513 	spi_imx->txfifo = 0;
1514 	spi_imx->remainder = 0;
1515 
1516 	/* fill in the fifo before timeout calculations if we are
1517 	 * interrupted here, then the data is getting transferred by
1518 	 * the HW while we are interrupted
1519 	 */
1520 	spi_imx_push(spi_imx);
1521 
1522 	timeout = spi_imx_calculate_timeout(spi_imx, transfer->len) + jiffies;
1523 	while (spi_imx->txfifo) {
1524 		/* RX */
1525 		while (spi_imx->txfifo &&
1526 		       spi_imx->devtype_data->rx_available(spi_imx)) {
1527 			spi_imx->rx(spi_imx);
1528 			spi_imx->txfifo--;
1529 		}
1530 
1531 		/* TX */
1532 		if (spi_imx->count) {
1533 			spi_imx_push(spi_imx);
1534 			continue;
1535 		}
1536 
1537 		if (spi_imx->txfifo &&
1538 		    time_after(jiffies, timeout)) {
1539 
1540 			dev_err_ratelimited(&spi->dev,
1541 					    "timeout period reached: jiffies: %lu- falling back to interrupt mode\n",
1542 					    jiffies - timeout);
1543 
1544 			/* fall back to interrupt mode */
1545 			return spi_imx_pio_transfer(spi, transfer);
1546 		}
1547 	}
1548 
1549 	return 0;
1550 }
1551 
1552 static int spi_imx_pio_transfer_slave(struct spi_device *spi,
1553 				      struct spi_transfer *transfer)
1554 {
1555 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1556 	int ret = 0;
1557 
1558 	if (is_imx53_ecspi(spi_imx) &&
1559 	    transfer->len > MX53_MAX_TRANSFER_BYTES) {
1560 		dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
1561 			MX53_MAX_TRANSFER_BYTES);
1562 		return -EMSGSIZE;
1563 	}
1564 
1565 	spi_imx->tx_buf = transfer->tx_buf;
1566 	spi_imx->rx_buf = transfer->rx_buf;
1567 	spi_imx->count = transfer->len;
1568 	spi_imx->txfifo = 0;
1569 	spi_imx->remainder = 0;
1570 
1571 	reinit_completion(&spi_imx->xfer_done);
1572 	spi_imx->slave_aborted = false;
1573 
1574 	spi_imx_push(spi_imx);
1575 
1576 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
1577 
1578 	if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
1579 	    spi_imx->slave_aborted) {
1580 		dev_dbg(&spi->dev, "interrupted\n");
1581 		ret = -EINTR;
1582 	}
1583 
1584 	/* ecspi has a HW issue when works in Slave mode,
1585 	 * after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
1586 	 * ECSPI_TXDATA keeps shift out the last word data,
1587 	 * so we have to disable ECSPI when in slave mode after the
1588 	 * transfer completes
1589 	 */
1590 	if (spi_imx->devtype_data->disable)
1591 		spi_imx->devtype_data->disable(spi_imx);
1592 
1593 	return ret;
1594 }
1595 
1596 static int spi_imx_transfer_one(struct spi_controller *controller,
1597 				struct spi_device *spi,
1598 				struct spi_transfer *transfer)
1599 {
1600 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1601 	unsigned long hz_per_byte, byte_limit;
1602 
1603 	spi_imx_setupxfer(spi, transfer);
1604 	transfer->effective_speed_hz = spi_imx->spi_bus_clk;
1605 
1606 	/* flush rxfifo before transfer */
1607 	while (spi_imx->devtype_data->rx_available(spi_imx))
1608 		readl(spi_imx->base + MXC_CSPIRXDATA);
1609 
1610 	if (spi_imx->slave_mode)
1611 		return spi_imx_pio_transfer_slave(spi, transfer);
1612 
1613 	/*
1614 	 * If we decided in spi_imx_can_dma() that we want to do a DMA
1615 	 * transfer, the SPI transfer has already been mapped, so we
1616 	 * have to do the DMA transfer here.
1617 	 */
1618 	if (spi_imx->usedma)
1619 		return spi_imx_dma_transfer(spi_imx, transfer);
1620 	/*
1621 	 * Calculate the estimated time in us the transfer runs. Find
1622 	 * the number of Hz per byte per polling limit.
1623 	 */
1624 	hz_per_byte = polling_limit_us ? ((8 + 4) * USEC_PER_SEC) / polling_limit_us : 0;
1625 	byte_limit = hz_per_byte ? transfer->effective_speed_hz / hz_per_byte : 1;
1626 
1627 	/* run in polling mode for short transfers */
1628 	if (transfer->len < byte_limit)
1629 		return spi_imx_poll_transfer(spi, transfer);
1630 
1631 	return spi_imx_pio_transfer(spi, transfer);
1632 }
1633 
1634 static int spi_imx_setup(struct spi_device *spi)
1635 {
1636 	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1637 		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1638 
1639 	return 0;
1640 }
1641 
1642 static void spi_imx_cleanup(struct spi_device *spi)
1643 {
1644 }
1645 
1646 static int
1647 spi_imx_prepare_message(struct spi_controller *controller, struct spi_message *msg)
1648 {
1649 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1650 	int ret;
1651 
1652 	ret = pm_runtime_resume_and_get(spi_imx->dev);
1653 	if (ret < 0) {
1654 		dev_err(spi_imx->dev, "failed to enable clock\n");
1655 		return ret;
1656 	}
1657 
1658 	ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
1659 	if (ret) {
1660 		pm_runtime_mark_last_busy(spi_imx->dev);
1661 		pm_runtime_put_autosuspend(spi_imx->dev);
1662 	}
1663 
1664 	return ret;
1665 }
1666 
1667 static int
1668 spi_imx_unprepare_message(struct spi_controller *controller, struct spi_message *msg)
1669 {
1670 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1671 
1672 	pm_runtime_mark_last_busy(spi_imx->dev);
1673 	pm_runtime_put_autosuspend(spi_imx->dev);
1674 	return 0;
1675 }
1676 
1677 static int spi_imx_slave_abort(struct spi_controller *controller)
1678 {
1679 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1680 
1681 	spi_imx->slave_aborted = true;
1682 	complete(&spi_imx->xfer_done);
1683 
1684 	return 0;
1685 }
1686 
1687 static int spi_imx_probe(struct platform_device *pdev)
1688 {
1689 	struct device_node *np = pdev->dev.of_node;
1690 	struct spi_controller *controller;
1691 	struct spi_imx_data *spi_imx;
1692 	struct resource *res;
1693 	int ret, irq, spi_drctl;
1694 	const struct spi_imx_devtype_data *devtype_data =
1695 			of_device_get_match_data(&pdev->dev);
1696 	bool slave_mode;
1697 	u32 val;
1698 
1699 	slave_mode = devtype_data->has_slavemode &&
1700 			of_property_read_bool(np, "spi-slave");
1701 	if (slave_mode)
1702 		controller = spi_alloc_slave(&pdev->dev,
1703 					     sizeof(struct spi_imx_data));
1704 	else
1705 		controller = spi_alloc_master(&pdev->dev,
1706 					      sizeof(struct spi_imx_data));
1707 	if (!controller)
1708 		return -ENOMEM;
1709 
1710 	ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
1711 	if ((ret < 0) || (spi_drctl >= 0x3)) {
1712 		/* '11' is reserved */
1713 		spi_drctl = 0;
1714 	}
1715 
1716 	platform_set_drvdata(pdev, controller);
1717 
1718 	controller->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1719 	controller->bus_num = np ? -1 : pdev->id;
1720 	controller->use_gpio_descriptors = true;
1721 
1722 	spi_imx = spi_controller_get_devdata(controller);
1723 	spi_imx->controller = controller;
1724 	spi_imx->dev = &pdev->dev;
1725 	spi_imx->slave_mode = slave_mode;
1726 
1727 	spi_imx->devtype_data = devtype_data;
1728 
1729 	/*
1730 	 * Get number of chip selects from device properties. This can be
1731 	 * coming from device tree or boardfiles, if it is not defined,
1732 	 * a default value of 3 chip selects will be used, as all the legacy
1733 	 * board files have <= 3 chip selects.
1734 	 */
1735 	if (!device_property_read_u32(&pdev->dev, "num-cs", &val))
1736 		controller->num_chipselect = val;
1737 	else
1738 		controller->num_chipselect = 3;
1739 
1740 	spi_imx->controller->transfer_one = spi_imx_transfer_one;
1741 	spi_imx->controller->setup = spi_imx_setup;
1742 	spi_imx->controller->cleanup = spi_imx_cleanup;
1743 	spi_imx->controller->prepare_message = spi_imx_prepare_message;
1744 	spi_imx->controller->unprepare_message = spi_imx_unprepare_message;
1745 	spi_imx->controller->slave_abort = spi_imx_slave_abort;
1746 	spi_imx->controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_NO_CS;
1747 
1748 	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
1749 	    is_imx53_ecspi(spi_imx))
1750 		spi_imx->controller->mode_bits |= SPI_LOOP | SPI_READY;
1751 
1752 	if (is_imx51_ecspi(spi_imx) || is_imx53_ecspi(spi_imx))
1753 		spi_imx->controller->mode_bits |= SPI_RX_CPHA_FLIP;
1754 
1755 	if (is_imx51_ecspi(spi_imx) &&
1756 	    device_property_read_u32(&pdev->dev, "cs-gpios", NULL))
1757 		/*
1758 		 * When using HW-CS implementing SPI_CS_WORD can be done by just
1759 		 * setting the burst length to the word size. This is
1760 		 * considerably faster than manually controlling the CS.
1761 		 */
1762 		spi_imx->controller->mode_bits |= SPI_CS_WORD;
1763 
1764 	spi_imx->spi_drctl = spi_drctl;
1765 
1766 	init_completion(&spi_imx->xfer_done);
1767 
1768 	spi_imx->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1769 	if (IS_ERR(spi_imx->base)) {
1770 		ret = PTR_ERR(spi_imx->base);
1771 		goto out_controller_put;
1772 	}
1773 	spi_imx->base_phys = res->start;
1774 
1775 	irq = platform_get_irq(pdev, 0);
1776 	if (irq < 0) {
1777 		ret = irq;
1778 		goto out_controller_put;
1779 	}
1780 
1781 	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1782 			       dev_name(&pdev->dev), spi_imx);
1783 	if (ret) {
1784 		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1785 		goto out_controller_put;
1786 	}
1787 
1788 	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1789 	if (IS_ERR(spi_imx->clk_ipg)) {
1790 		ret = PTR_ERR(spi_imx->clk_ipg);
1791 		goto out_controller_put;
1792 	}
1793 
1794 	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1795 	if (IS_ERR(spi_imx->clk_per)) {
1796 		ret = PTR_ERR(spi_imx->clk_per);
1797 		goto out_controller_put;
1798 	}
1799 
1800 	ret = clk_prepare_enable(spi_imx->clk_per);
1801 	if (ret)
1802 		goto out_controller_put;
1803 
1804 	ret = clk_prepare_enable(spi_imx->clk_ipg);
1805 	if (ret)
1806 		goto out_put_per;
1807 
1808 	pm_runtime_set_autosuspend_delay(spi_imx->dev, MXC_RPM_TIMEOUT);
1809 	pm_runtime_use_autosuspend(spi_imx->dev);
1810 	pm_runtime_get_noresume(spi_imx->dev);
1811 	pm_runtime_set_active(spi_imx->dev);
1812 	pm_runtime_enable(spi_imx->dev);
1813 
1814 	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1815 	/*
1816 	 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1817 	 * if validated on other chips.
1818 	 */
1819 	if (spi_imx->devtype_data->has_dmamode) {
1820 		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, controller);
1821 		if (ret == -EPROBE_DEFER)
1822 			goto out_runtime_pm_put;
1823 
1824 		if (ret < 0)
1825 			dev_dbg(&pdev->dev, "dma setup error %d, use pio\n",
1826 				ret);
1827 	}
1828 
1829 	spi_imx->devtype_data->reset(spi_imx);
1830 
1831 	spi_imx->devtype_data->intctrl(spi_imx, 0);
1832 
1833 	controller->dev.of_node = pdev->dev.of_node;
1834 	ret = spi_register_controller(controller);
1835 	if (ret) {
1836 		dev_err_probe(&pdev->dev, ret, "register controller failed\n");
1837 		goto out_register_controller;
1838 	}
1839 
1840 	pm_runtime_mark_last_busy(spi_imx->dev);
1841 	pm_runtime_put_autosuspend(spi_imx->dev);
1842 
1843 	return ret;
1844 
1845 out_register_controller:
1846 	if (spi_imx->devtype_data->has_dmamode)
1847 		spi_imx_sdma_exit(spi_imx);
1848 out_runtime_pm_put:
1849 	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1850 	pm_runtime_set_suspended(&pdev->dev);
1851 	pm_runtime_disable(spi_imx->dev);
1852 
1853 	clk_disable_unprepare(spi_imx->clk_ipg);
1854 out_put_per:
1855 	clk_disable_unprepare(spi_imx->clk_per);
1856 out_controller_put:
1857 	spi_controller_put(controller);
1858 
1859 	return ret;
1860 }
1861 
1862 static void spi_imx_remove(struct platform_device *pdev)
1863 {
1864 	struct spi_controller *controller = platform_get_drvdata(pdev);
1865 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1866 	int ret;
1867 
1868 	spi_unregister_controller(controller);
1869 
1870 	ret = pm_runtime_get_sync(spi_imx->dev);
1871 	if (ret >= 0)
1872 		writel(0, spi_imx->base + MXC_CSPICTRL);
1873 	else
1874 		dev_warn(spi_imx->dev, "failed to enable clock, skip hw disable\n");
1875 
1876 	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1877 	pm_runtime_put_sync(spi_imx->dev);
1878 	pm_runtime_disable(spi_imx->dev);
1879 
1880 	spi_imx_sdma_exit(spi_imx);
1881 }
1882 
1883 static int __maybe_unused spi_imx_runtime_resume(struct device *dev)
1884 {
1885 	struct spi_controller *controller = dev_get_drvdata(dev);
1886 	struct spi_imx_data *spi_imx;
1887 	int ret;
1888 
1889 	spi_imx = spi_controller_get_devdata(controller);
1890 
1891 	ret = clk_prepare_enable(spi_imx->clk_per);
1892 	if (ret)
1893 		return ret;
1894 
1895 	ret = clk_prepare_enable(spi_imx->clk_ipg);
1896 	if (ret) {
1897 		clk_disable_unprepare(spi_imx->clk_per);
1898 		return ret;
1899 	}
1900 
1901 	return 0;
1902 }
1903 
1904 static int __maybe_unused spi_imx_runtime_suspend(struct device *dev)
1905 {
1906 	struct spi_controller *controller = dev_get_drvdata(dev);
1907 	struct spi_imx_data *spi_imx;
1908 
1909 	spi_imx = spi_controller_get_devdata(controller);
1910 
1911 	clk_disable_unprepare(spi_imx->clk_per);
1912 	clk_disable_unprepare(spi_imx->clk_ipg);
1913 
1914 	return 0;
1915 }
1916 
1917 static int __maybe_unused spi_imx_suspend(struct device *dev)
1918 {
1919 	pinctrl_pm_select_sleep_state(dev);
1920 	return 0;
1921 }
1922 
1923 static int __maybe_unused spi_imx_resume(struct device *dev)
1924 {
1925 	pinctrl_pm_select_default_state(dev);
1926 	return 0;
1927 }
1928 
1929 static const struct dev_pm_ops imx_spi_pm = {
1930 	SET_RUNTIME_PM_OPS(spi_imx_runtime_suspend,
1931 				spi_imx_runtime_resume, NULL)
1932 	SET_SYSTEM_SLEEP_PM_OPS(spi_imx_suspend, spi_imx_resume)
1933 };
1934 
1935 static struct platform_driver spi_imx_driver = {
1936 	.driver = {
1937 		   .name = DRIVER_NAME,
1938 		   .of_match_table = spi_imx_dt_ids,
1939 		   .pm = &imx_spi_pm,
1940 	},
1941 	.probe = spi_imx_probe,
1942 	.remove_new = spi_imx_remove,
1943 };
1944 module_platform_driver(spi_imx_driver);
1945 
1946 MODULE_DESCRIPTION("i.MX SPI Controller driver");
1947 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1948 MODULE_LICENSE("GPL");
1949 MODULE_ALIAS("platform:" DRIVER_NAME);
1950