xref: /openbmc/linux/drivers/spi/spi-imx.c (revision 7b7090b4)
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 	void (*disable_dma)(struct spi_imx_data *spi_imx);
81 	bool has_dmamode;
82 	bool has_slavemode;
83 	unsigned int fifo_size;
84 	bool dynamic_burst;
85 	/*
86 	 * ERR009165 fixed or not:
87 	 * https://www.nxp.com/docs/en/errata/IMX6DQCE.pdf
88 	 */
89 	bool tx_glitch_fixed;
90 	enum spi_imx_devtype devtype;
91 };
92 
93 struct spi_imx_data {
94 	struct spi_controller *controller;
95 	struct device *dev;
96 
97 	struct completion xfer_done;
98 	void __iomem *base;
99 	unsigned long base_phys;
100 
101 	struct clk *clk_per;
102 	struct clk *clk_ipg;
103 	unsigned long spi_clk;
104 	unsigned int spi_bus_clk;
105 
106 	unsigned int bits_per_word;
107 	unsigned int spi_drctl;
108 
109 	unsigned int count, remainder;
110 	void (*tx)(struct spi_imx_data *spi_imx);
111 	void (*rx)(struct spi_imx_data *spi_imx);
112 	void *rx_buf;
113 	const void *tx_buf;
114 	unsigned int txfifo; /* number of words pushed in tx FIFO */
115 	unsigned int dynamic_burst;
116 	bool rx_only;
117 
118 	/* Slave mode */
119 	bool slave_mode;
120 	bool slave_aborted;
121 	unsigned int slave_burst;
122 
123 	/* DMA */
124 	bool usedma;
125 	u32 wml;
126 	struct completion dma_rx_completion;
127 	struct completion dma_tx_completion;
128 
129 	const struct spi_imx_devtype_data *devtype_data;
130 };
131 
132 static inline int is_imx27_cspi(struct spi_imx_data *d)
133 {
134 	return d->devtype_data->devtype == IMX27_CSPI;
135 }
136 
137 static inline int is_imx35_cspi(struct spi_imx_data *d)
138 {
139 	return d->devtype_data->devtype == IMX35_CSPI;
140 }
141 
142 static inline int is_imx51_ecspi(struct spi_imx_data *d)
143 {
144 	return d->devtype_data->devtype == IMX51_ECSPI;
145 }
146 
147 static inline int is_imx53_ecspi(struct spi_imx_data *d)
148 {
149 	return d->devtype_data->devtype == IMX53_ECSPI;
150 }
151 
152 #define MXC_SPI_BUF_RX(type)						\
153 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
154 {									\
155 	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
156 									\
157 	if (spi_imx->rx_buf) {						\
158 		*(type *)spi_imx->rx_buf = val;				\
159 		spi_imx->rx_buf += sizeof(type);			\
160 	}								\
161 									\
162 	spi_imx->remainder -= sizeof(type);				\
163 }
164 
165 #define MXC_SPI_BUF_TX(type)						\
166 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
167 {									\
168 	type val = 0;							\
169 									\
170 	if (spi_imx->tx_buf) {						\
171 		val = *(type *)spi_imx->tx_buf;				\
172 		spi_imx->tx_buf += sizeof(type);			\
173 	}								\
174 									\
175 	spi_imx->count -= sizeof(type);					\
176 									\
177 	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
178 }
179 
180 MXC_SPI_BUF_RX(u8)
181 MXC_SPI_BUF_TX(u8)
182 MXC_SPI_BUF_RX(u16)
183 MXC_SPI_BUF_TX(u16)
184 MXC_SPI_BUF_RX(u32)
185 MXC_SPI_BUF_TX(u32)
186 
187 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
188  * (which is currently not the case in this driver)
189  */
190 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
191 	256, 384, 512, 768, 1024};
192 
193 /* MX21, MX27 */
194 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
195 		unsigned int fspi, unsigned int max, unsigned int *fres)
196 {
197 	int i;
198 
199 	for (i = 2; i < max; i++)
200 		if (fspi * mxc_clkdivs[i] >= fin)
201 			break;
202 
203 	*fres = fin / mxc_clkdivs[i];
204 	return i;
205 }
206 
207 /* MX1, MX31, MX35, MX51 CSPI */
208 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
209 		unsigned int fspi, unsigned int *fres)
210 {
211 	int i, div = 4;
212 
213 	for (i = 0; i < 7; i++) {
214 		if (fspi * div >= fin)
215 			goto out;
216 		div <<= 1;
217 	}
218 
219 out:
220 	*fres = fin / div;
221 	return i;
222 }
223 
224 static int spi_imx_bytes_per_word(const int bits_per_word)
225 {
226 	if (bits_per_word <= 8)
227 		return 1;
228 	else if (bits_per_word <= 16)
229 		return 2;
230 	else
231 		return 4;
232 }
233 
234 static bool spi_imx_can_dma(struct spi_controller *controller, struct spi_device *spi,
235 			 struct spi_transfer *transfer)
236 {
237 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
238 
239 	if (!use_dma || controller->fallback)
240 		return false;
241 
242 	if (!controller->dma_rx)
243 		return false;
244 
245 	if (spi_imx->slave_mode)
246 		return false;
247 
248 	if (transfer->len < spi_imx->devtype_data->fifo_size)
249 		return false;
250 
251 	spi_imx->dynamic_burst = 0;
252 
253 	return true;
254 }
255 
256 #define MX51_ECSPI_CTRL		0x08
257 #define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
258 #define MX51_ECSPI_CTRL_XCH		(1 <<  2)
259 #define MX51_ECSPI_CTRL_SMC		(1 << 3)
260 #define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
261 #define MX51_ECSPI_CTRL_DRCTL(drctl)	((drctl) << 16)
262 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
263 #define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
264 #define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
265 #define MX51_ECSPI_CTRL_BL_OFFSET	20
266 #define MX51_ECSPI_CTRL_BL_MASK		(0xfff << 20)
267 
268 #define MX51_ECSPI_CONFIG	0x0c
269 #define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
270 #define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
271 #define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
272 #define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
273 #define MX51_ECSPI_CONFIG_SCLKCTL(cs)	(1 << ((cs) + 20))
274 
275 #define MX51_ECSPI_INT		0x10
276 #define MX51_ECSPI_INT_TEEN		(1 <<  0)
277 #define MX51_ECSPI_INT_RREN		(1 <<  3)
278 #define MX51_ECSPI_INT_RDREN		(1 <<  4)
279 
280 #define MX51_ECSPI_DMA		0x14
281 #define MX51_ECSPI_DMA_TX_WML(wml)	((wml) & 0x3f)
282 #define MX51_ECSPI_DMA_RX_WML(wml)	(((wml) & 0x3f) << 16)
283 #define MX51_ECSPI_DMA_RXT_WML(wml)	(((wml) & 0x3f) << 24)
284 
285 #define MX51_ECSPI_DMA_TEDEN		(1 << 7)
286 #define MX51_ECSPI_DMA_RXDEN		(1 << 23)
287 #define MX51_ECSPI_DMA_RXTDEN		(1 << 31)
288 
289 #define MX51_ECSPI_STAT		0x18
290 #define MX51_ECSPI_STAT_RR		(1 <<  3)
291 
292 #define MX51_ECSPI_TESTREG	0x20
293 #define MX51_ECSPI_TESTREG_LBC	BIT(31)
294 
295 static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
296 {
297 	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
298 
299 	if (spi_imx->rx_buf) {
300 #ifdef __LITTLE_ENDIAN
301 		unsigned int bytes_per_word;
302 
303 		bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
304 		if (bytes_per_word == 1)
305 			swab32s(&val);
306 		else if (bytes_per_word == 2)
307 			swahw32s(&val);
308 #endif
309 		*(u32 *)spi_imx->rx_buf = val;
310 		spi_imx->rx_buf += sizeof(u32);
311 	}
312 
313 	spi_imx->remainder -= sizeof(u32);
314 }
315 
316 static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
317 {
318 	int unaligned;
319 	u32 val;
320 
321 	unaligned = spi_imx->remainder % 4;
322 
323 	if (!unaligned) {
324 		spi_imx_buf_rx_swap_u32(spi_imx);
325 		return;
326 	}
327 
328 	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
329 		spi_imx_buf_rx_u16(spi_imx);
330 		return;
331 	}
332 
333 	val = readl(spi_imx->base + MXC_CSPIRXDATA);
334 
335 	while (unaligned--) {
336 		if (spi_imx->rx_buf) {
337 			*(u8 *)spi_imx->rx_buf = (val >> (8 * unaligned)) & 0xff;
338 			spi_imx->rx_buf++;
339 		}
340 		spi_imx->remainder--;
341 	}
342 }
343 
344 static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
345 {
346 	u32 val = 0;
347 #ifdef __LITTLE_ENDIAN
348 	unsigned int bytes_per_word;
349 #endif
350 
351 	if (spi_imx->tx_buf) {
352 		val = *(u32 *)spi_imx->tx_buf;
353 		spi_imx->tx_buf += sizeof(u32);
354 	}
355 
356 	spi_imx->count -= sizeof(u32);
357 #ifdef __LITTLE_ENDIAN
358 	bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
359 
360 	if (bytes_per_word == 1)
361 		swab32s(&val);
362 	else if (bytes_per_word == 2)
363 		swahw32s(&val);
364 #endif
365 	writel(val, spi_imx->base + MXC_CSPITXDATA);
366 }
367 
368 static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
369 {
370 	int unaligned;
371 	u32 val = 0;
372 
373 	unaligned = spi_imx->count % 4;
374 
375 	if (!unaligned) {
376 		spi_imx_buf_tx_swap_u32(spi_imx);
377 		return;
378 	}
379 
380 	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
381 		spi_imx_buf_tx_u16(spi_imx);
382 		return;
383 	}
384 
385 	while (unaligned--) {
386 		if (spi_imx->tx_buf) {
387 			val |= *(u8 *)spi_imx->tx_buf << (8 * unaligned);
388 			spi_imx->tx_buf++;
389 		}
390 		spi_imx->count--;
391 	}
392 
393 	writel(val, spi_imx->base + MXC_CSPITXDATA);
394 }
395 
396 static void mx53_ecspi_rx_slave(struct spi_imx_data *spi_imx)
397 {
398 	u32 val = be32_to_cpu(readl(spi_imx->base + MXC_CSPIRXDATA));
399 
400 	if (spi_imx->rx_buf) {
401 		int n_bytes = spi_imx->slave_burst % sizeof(val);
402 
403 		if (!n_bytes)
404 			n_bytes = sizeof(val);
405 
406 		memcpy(spi_imx->rx_buf,
407 		       ((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
408 
409 		spi_imx->rx_buf += n_bytes;
410 		spi_imx->slave_burst -= n_bytes;
411 	}
412 
413 	spi_imx->remainder -= sizeof(u32);
414 }
415 
416 static void mx53_ecspi_tx_slave(struct spi_imx_data *spi_imx)
417 {
418 	u32 val = 0;
419 	int n_bytes = spi_imx->count % sizeof(val);
420 
421 	if (!n_bytes)
422 		n_bytes = sizeof(val);
423 
424 	if (spi_imx->tx_buf) {
425 		memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
426 		       spi_imx->tx_buf, n_bytes);
427 		val = cpu_to_be32(val);
428 		spi_imx->tx_buf += n_bytes;
429 	}
430 
431 	spi_imx->count -= n_bytes;
432 
433 	writel(val, spi_imx->base + MXC_CSPITXDATA);
434 }
435 
436 /* MX51 eCSPI */
437 static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
438 				      unsigned int fspi, unsigned int *fres)
439 {
440 	/*
441 	 * there are two 4-bit dividers, the pre-divider divides by
442 	 * $pre, the post-divider by 2^$post
443 	 */
444 	unsigned int pre, post;
445 	unsigned int fin = spi_imx->spi_clk;
446 
447 	if (unlikely(fspi > fin))
448 		return 0;
449 
450 	post = fls(fin) - fls(fspi);
451 	if (fin > fspi << post)
452 		post++;
453 
454 	/* now we have: (fin <= fspi << post) with post being minimal */
455 
456 	post = max(4U, post) - 4;
457 	if (unlikely(post > 0xf)) {
458 		dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
459 				fspi, fin);
460 		return 0xff;
461 	}
462 
463 	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
464 
465 	dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
466 			__func__, fin, fspi, post, pre);
467 
468 	/* Resulting frequency for the SCLK line. */
469 	*fres = (fin / (pre + 1)) >> post;
470 
471 	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
472 		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
473 }
474 
475 static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
476 {
477 	unsigned int val = 0;
478 
479 	if (enable & MXC_INT_TE)
480 		val |= MX51_ECSPI_INT_TEEN;
481 
482 	if (enable & MXC_INT_RR)
483 		val |= MX51_ECSPI_INT_RREN;
484 
485 	if (enable & MXC_INT_RDR)
486 		val |= MX51_ECSPI_INT_RDREN;
487 
488 	writel(val, spi_imx->base + MX51_ECSPI_INT);
489 }
490 
491 static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
492 {
493 	u32 reg;
494 
495 	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
496 	reg |= MX51_ECSPI_CTRL_XCH;
497 	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
498 }
499 
500 static void mx51_disable_dma(struct spi_imx_data *spi_imx)
501 {
502 	writel(0, spi_imx->base + MX51_ECSPI_DMA);
503 }
504 
505 static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
506 {
507 	u32 ctrl;
508 
509 	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
510 	ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
511 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
512 }
513 
514 static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
515 				      struct spi_message *msg)
516 {
517 	struct spi_device *spi = msg->spi;
518 	struct spi_transfer *xfer;
519 	u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
520 	u32 min_speed_hz = ~0U;
521 	u32 testreg, delay;
522 	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
523 	u32 current_cfg = cfg;
524 
525 	/* set Master or Slave mode */
526 	if (spi_imx->slave_mode)
527 		ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
528 	else
529 		ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
530 
531 	/*
532 	 * Enable SPI_RDY handling (falling edge/level triggered).
533 	 */
534 	if (spi->mode & SPI_READY)
535 		ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
536 
537 	/* set chip select to use */
538 	ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
539 
540 	/*
541 	 * The ctrl register must be written first, with the EN bit set other
542 	 * registers must not be written to.
543 	 */
544 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
545 
546 	testreg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
547 	if (spi->mode & SPI_LOOP)
548 		testreg |= MX51_ECSPI_TESTREG_LBC;
549 	else
550 		testreg &= ~MX51_ECSPI_TESTREG_LBC;
551 	writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
552 
553 	/*
554 	 * eCSPI burst completion by Chip Select signal in Slave mode
555 	 * is not functional for imx53 Soc, config SPI burst completed when
556 	 * BURST_LENGTH + 1 bits are received
557 	 */
558 	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
559 		cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
560 	else
561 		cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
562 
563 	if (spi->mode & SPI_CPOL) {
564 		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
565 		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
566 	} else {
567 		cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
568 		cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
569 	}
570 
571 	if (spi->mode & SPI_CS_HIGH)
572 		cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
573 	else
574 		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
575 
576 	if (cfg == current_cfg)
577 		return 0;
578 
579 	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
580 
581 	/*
582 	 * Wait until the changes in the configuration register CONFIGREG
583 	 * propagate into the hardware. It takes exactly one tick of the
584 	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
585 	 * effect of the delay it takes for the hardware to apply changes
586 	 * is noticable if the SCLK clock run very slow. In such a case, if
587 	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
588 	 * be asserted before the SCLK polarity changes, which would disrupt
589 	 * the SPI communication as the device on the other end would consider
590 	 * the change of SCLK polarity as a clock tick already.
591 	 *
592 	 * Because spi_imx->spi_bus_clk is only set in prepare_message
593 	 * callback, iterate over all the transfers in spi_message, find the
594 	 * one with lowest bus frequency, and use that bus frequency for the
595 	 * delay calculation. In case all transfers have speed_hz == 0, then
596 	 * min_speed_hz is ~0 and the resulting delay is zero.
597 	 */
598 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
599 		if (!xfer->speed_hz)
600 			continue;
601 		min_speed_hz = min(xfer->speed_hz, min_speed_hz);
602 	}
603 
604 	delay = (2 * 1000000) / min_speed_hz;
605 	if (likely(delay < 10))	/* SCLK is faster than 200 kHz */
606 		udelay(delay);
607 	else			/* SCLK is _very_ slow */
608 		usleep_range(delay, delay + 10);
609 
610 	return 0;
611 }
612 
613 static void mx51_configure_cpha(struct spi_imx_data *spi_imx,
614 				struct spi_device *spi)
615 {
616 	bool cpha = (spi->mode & SPI_CPHA);
617 	bool flip_cpha = (spi->mode & SPI_RX_CPHA_FLIP) && spi_imx->rx_only;
618 	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
619 
620 	/* Flip cpha logical value iff flip_cpha */
621 	cpha ^= flip_cpha;
622 
623 	if (cpha)
624 		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
625 	else
626 		cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
627 
628 	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
629 }
630 
631 static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
632 				       struct spi_device *spi)
633 {
634 	u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
635 	u32 clk;
636 
637 	/* Clear BL field and set the right value */
638 	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
639 	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
640 		ctrl |= (spi_imx->slave_burst * 8 - 1)
641 			<< MX51_ECSPI_CTRL_BL_OFFSET;
642 	else
643 		ctrl |= (spi_imx->bits_per_word - 1)
644 			<< MX51_ECSPI_CTRL_BL_OFFSET;
645 
646 	/* set clock speed */
647 	ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
648 		  0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
649 	ctrl |= mx51_ecspi_clkdiv(spi_imx, spi_imx->spi_bus_clk, &clk);
650 	spi_imx->spi_bus_clk = clk;
651 
652 	mx51_configure_cpha(spi_imx, spi);
653 
654 	/*
655 	 * ERR009165: work in XHC mode instead of SMC as PIO on the chips
656 	 * before i.mx6ul.
657 	 */
658 	if (spi_imx->usedma && spi_imx->devtype_data->tx_glitch_fixed)
659 		ctrl |= MX51_ECSPI_CTRL_SMC;
660 	else
661 		ctrl &= ~MX51_ECSPI_CTRL_SMC;
662 
663 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
664 
665 	return 0;
666 }
667 
668 static void mx51_setup_wml(struct spi_imx_data *spi_imx)
669 {
670 	u32 tx_wml = 0;
671 
672 	if (spi_imx->devtype_data->tx_glitch_fixed)
673 		tx_wml = spi_imx->wml;
674 	/*
675 	 * Configure the DMA register: setup the watermark
676 	 * and enable DMA request.
677 	 */
678 	writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) |
679 		MX51_ECSPI_DMA_TX_WML(tx_wml) |
680 		MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
681 		MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
682 		MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
683 }
684 
685 static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
686 {
687 	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
688 }
689 
690 static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
691 {
692 	/* drain receive buffer */
693 	while (mx51_ecspi_rx_available(spi_imx))
694 		readl(spi_imx->base + MXC_CSPIRXDATA);
695 }
696 
697 #define MX31_INTREG_TEEN	(1 << 0)
698 #define MX31_INTREG_RREN	(1 << 3)
699 
700 #define MX31_CSPICTRL_ENABLE	(1 << 0)
701 #define MX31_CSPICTRL_MASTER	(1 << 1)
702 #define MX31_CSPICTRL_XCH	(1 << 2)
703 #define MX31_CSPICTRL_SMC	(1 << 3)
704 #define MX31_CSPICTRL_POL	(1 << 4)
705 #define MX31_CSPICTRL_PHA	(1 << 5)
706 #define MX31_CSPICTRL_SSCTL	(1 << 6)
707 #define MX31_CSPICTRL_SSPOL	(1 << 7)
708 #define MX31_CSPICTRL_BC_SHIFT	8
709 #define MX35_CSPICTRL_BL_SHIFT	20
710 #define MX31_CSPICTRL_CS_SHIFT	24
711 #define MX35_CSPICTRL_CS_SHIFT	12
712 #define MX31_CSPICTRL_DR_SHIFT	16
713 
714 #define MX31_CSPI_DMAREG	0x10
715 #define MX31_DMAREG_RH_DEN	(1<<4)
716 #define MX31_DMAREG_TH_DEN	(1<<1)
717 
718 #define MX31_CSPISTATUS		0x14
719 #define MX31_STATUS_RR		(1 << 3)
720 
721 #define MX31_CSPI_TESTREG	0x1C
722 #define MX31_TEST_LBC		(1 << 14)
723 
724 /* These functions also work for the i.MX35, but be aware that
725  * the i.MX35 has a slightly different register layout for bits
726  * we do not use here.
727  */
728 static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
729 {
730 	unsigned int val = 0;
731 
732 	if (enable & MXC_INT_TE)
733 		val |= MX31_INTREG_TEEN;
734 	if (enable & MXC_INT_RR)
735 		val |= MX31_INTREG_RREN;
736 
737 	writel(val, spi_imx->base + MXC_CSPIINT);
738 }
739 
740 static void mx31_trigger(struct spi_imx_data *spi_imx)
741 {
742 	unsigned int reg;
743 
744 	reg = readl(spi_imx->base + MXC_CSPICTRL);
745 	reg |= MX31_CSPICTRL_XCH;
746 	writel(reg, spi_imx->base + MXC_CSPICTRL);
747 }
748 
749 static int mx31_prepare_message(struct spi_imx_data *spi_imx,
750 				struct spi_message *msg)
751 {
752 	return 0;
753 }
754 
755 static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
756 				 struct spi_device *spi)
757 {
758 	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
759 	unsigned int clk;
760 
761 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
762 		MX31_CSPICTRL_DR_SHIFT;
763 	spi_imx->spi_bus_clk = clk;
764 
765 	if (is_imx35_cspi(spi_imx)) {
766 		reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
767 		reg |= MX31_CSPICTRL_SSCTL;
768 	} else {
769 		reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
770 	}
771 
772 	if (spi->mode & SPI_CPHA)
773 		reg |= MX31_CSPICTRL_PHA;
774 	if (spi->mode & SPI_CPOL)
775 		reg |= MX31_CSPICTRL_POL;
776 	if (spi->mode & SPI_CS_HIGH)
777 		reg |= MX31_CSPICTRL_SSPOL;
778 	if (!spi->cs_gpiod)
779 		reg |= (spi->chip_select) <<
780 			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
781 						  MX31_CSPICTRL_CS_SHIFT);
782 
783 	if (spi_imx->usedma)
784 		reg |= MX31_CSPICTRL_SMC;
785 
786 	writel(reg, spi_imx->base + MXC_CSPICTRL);
787 
788 	reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
789 	if (spi->mode & SPI_LOOP)
790 		reg |= MX31_TEST_LBC;
791 	else
792 		reg &= ~MX31_TEST_LBC;
793 	writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
794 
795 	if (spi_imx->usedma) {
796 		/*
797 		 * configure DMA requests when RXFIFO is half full and
798 		 * when TXFIFO is half empty
799 		 */
800 		writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
801 			spi_imx->base + MX31_CSPI_DMAREG);
802 	}
803 
804 	return 0;
805 }
806 
807 static int mx31_rx_available(struct spi_imx_data *spi_imx)
808 {
809 	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
810 }
811 
812 static void mx31_reset(struct spi_imx_data *spi_imx)
813 {
814 	/* drain receive buffer */
815 	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
816 		readl(spi_imx->base + MXC_CSPIRXDATA);
817 }
818 
819 #define MX21_INTREG_RR		(1 << 4)
820 #define MX21_INTREG_TEEN	(1 << 9)
821 #define MX21_INTREG_RREN	(1 << 13)
822 
823 #define MX21_CSPICTRL_POL	(1 << 5)
824 #define MX21_CSPICTRL_PHA	(1 << 6)
825 #define MX21_CSPICTRL_SSPOL	(1 << 8)
826 #define MX21_CSPICTRL_XCH	(1 << 9)
827 #define MX21_CSPICTRL_ENABLE	(1 << 10)
828 #define MX21_CSPICTRL_MASTER	(1 << 11)
829 #define MX21_CSPICTRL_DR_SHIFT	14
830 #define MX21_CSPICTRL_CS_SHIFT	19
831 
832 static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
833 {
834 	unsigned int val = 0;
835 
836 	if (enable & MXC_INT_TE)
837 		val |= MX21_INTREG_TEEN;
838 	if (enable & MXC_INT_RR)
839 		val |= MX21_INTREG_RREN;
840 
841 	writel(val, spi_imx->base + MXC_CSPIINT);
842 }
843 
844 static void mx21_trigger(struct spi_imx_data *spi_imx)
845 {
846 	unsigned int reg;
847 
848 	reg = readl(spi_imx->base + MXC_CSPICTRL);
849 	reg |= MX21_CSPICTRL_XCH;
850 	writel(reg, spi_imx->base + MXC_CSPICTRL);
851 }
852 
853 static int mx21_prepare_message(struct spi_imx_data *spi_imx,
854 				struct spi_message *msg)
855 {
856 	return 0;
857 }
858 
859 static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
860 				 struct spi_device *spi)
861 {
862 	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
863 	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
864 	unsigned int clk;
865 
866 	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, spi_imx->spi_bus_clk, max, &clk)
867 		<< MX21_CSPICTRL_DR_SHIFT;
868 	spi_imx->spi_bus_clk = clk;
869 
870 	reg |= spi_imx->bits_per_word - 1;
871 
872 	if (spi->mode & SPI_CPHA)
873 		reg |= MX21_CSPICTRL_PHA;
874 	if (spi->mode & SPI_CPOL)
875 		reg |= MX21_CSPICTRL_POL;
876 	if (spi->mode & SPI_CS_HIGH)
877 		reg |= MX21_CSPICTRL_SSPOL;
878 	if (!spi->cs_gpiod)
879 		reg |= spi->chip_select << MX21_CSPICTRL_CS_SHIFT;
880 
881 	writel(reg, spi_imx->base + MXC_CSPICTRL);
882 
883 	return 0;
884 }
885 
886 static int mx21_rx_available(struct spi_imx_data *spi_imx)
887 {
888 	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
889 }
890 
891 static void mx21_reset(struct spi_imx_data *spi_imx)
892 {
893 	writel(1, spi_imx->base + MXC_RESET);
894 }
895 
896 #define MX1_INTREG_RR		(1 << 3)
897 #define MX1_INTREG_TEEN		(1 << 8)
898 #define MX1_INTREG_RREN		(1 << 11)
899 
900 #define MX1_CSPICTRL_POL	(1 << 4)
901 #define MX1_CSPICTRL_PHA	(1 << 5)
902 #define MX1_CSPICTRL_XCH	(1 << 8)
903 #define MX1_CSPICTRL_ENABLE	(1 << 9)
904 #define MX1_CSPICTRL_MASTER	(1 << 10)
905 #define MX1_CSPICTRL_DR_SHIFT	13
906 
907 static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
908 {
909 	unsigned int val = 0;
910 
911 	if (enable & MXC_INT_TE)
912 		val |= MX1_INTREG_TEEN;
913 	if (enable & MXC_INT_RR)
914 		val |= MX1_INTREG_RREN;
915 
916 	writel(val, spi_imx->base + MXC_CSPIINT);
917 }
918 
919 static void mx1_trigger(struct spi_imx_data *spi_imx)
920 {
921 	unsigned int reg;
922 
923 	reg = readl(spi_imx->base + MXC_CSPICTRL);
924 	reg |= MX1_CSPICTRL_XCH;
925 	writel(reg, spi_imx->base + MXC_CSPICTRL);
926 }
927 
928 static int mx1_prepare_message(struct spi_imx_data *spi_imx,
929 			       struct spi_message *msg)
930 {
931 	return 0;
932 }
933 
934 static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
935 				struct spi_device *spi)
936 {
937 	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
938 	unsigned int clk;
939 
940 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
941 		MX1_CSPICTRL_DR_SHIFT;
942 	spi_imx->spi_bus_clk = clk;
943 
944 	reg |= spi_imx->bits_per_word - 1;
945 
946 	if (spi->mode & SPI_CPHA)
947 		reg |= MX1_CSPICTRL_PHA;
948 	if (spi->mode & SPI_CPOL)
949 		reg |= MX1_CSPICTRL_POL;
950 
951 	writel(reg, spi_imx->base + MXC_CSPICTRL);
952 
953 	return 0;
954 }
955 
956 static int mx1_rx_available(struct spi_imx_data *spi_imx)
957 {
958 	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
959 }
960 
961 static void mx1_reset(struct spi_imx_data *spi_imx)
962 {
963 	writel(1, spi_imx->base + MXC_RESET);
964 }
965 
966 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
967 	.intctrl = mx1_intctrl,
968 	.prepare_message = mx1_prepare_message,
969 	.prepare_transfer = mx1_prepare_transfer,
970 	.trigger = mx1_trigger,
971 	.rx_available = mx1_rx_available,
972 	.reset = mx1_reset,
973 	.fifo_size = 8,
974 	.has_dmamode = false,
975 	.dynamic_burst = false,
976 	.has_slavemode = false,
977 	.devtype = IMX1_CSPI,
978 };
979 
980 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
981 	.intctrl = mx21_intctrl,
982 	.prepare_message = mx21_prepare_message,
983 	.prepare_transfer = mx21_prepare_transfer,
984 	.trigger = mx21_trigger,
985 	.rx_available = mx21_rx_available,
986 	.reset = mx21_reset,
987 	.fifo_size = 8,
988 	.has_dmamode = false,
989 	.dynamic_burst = false,
990 	.has_slavemode = false,
991 	.devtype = IMX21_CSPI,
992 };
993 
994 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
995 	/* i.mx27 cspi shares the functions with i.mx21 one */
996 	.intctrl = mx21_intctrl,
997 	.prepare_message = mx21_prepare_message,
998 	.prepare_transfer = mx21_prepare_transfer,
999 	.trigger = mx21_trigger,
1000 	.rx_available = mx21_rx_available,
1001 	.reset = mx21_reset,
1002 	.fifo_size = 8,
1003 	.has_dmamode = false,
1004 	.dynamic_burst = false,
1005 	.has_slavemode = false,
1006 	.devtype = IMX27_CSPI,
1007 };
1008 
1009 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
1010 	.intctrl = mx31_intctrl,
1011 	.prepare_message = mx31_prepare_message,
1012 	.prepare_transfer = mx31_prepare_transfer,
1013 	.trigger = mx31_trigger,
1014 	.rx_available = mx31_rx_available,
1015 	.reset = mx31_reset,
1016 	.fifo_size = 8,
1017 	.has_dmamode = false,
1018 	.dynamic_burst = false,
1019 	.has_slavemode = false,
1020 	.devtype = IMX31_CSPI,
1021 };
1022 
1023 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
1024 	/* i.mx35 and later cspi shares the functions with i.mx31 one */
1025 	.intctrl = mx31_intctrl,
1026 	.prepare_message = mx31_prepare_message,
1027 	.prepare_transfer = mx31_prepare_transfer,
1028 	.trigger = mx31_trigger,
1029 	.rx_available = mx31_rx_available,
1030 	.reset = mx31_reset,
1031 	.fifo_size = 8,
1032 	.has_dmamode = true,
1033 	.dynamic_burst = false,
1034 	.has_slavemode = false,
1035 	.devtype = IMX35_CSPI,
1036 };
1037 
1038 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
1039 	.intctrl = mx51_ecspi_intctrl,
1040 	.prepare_message = mx51_ecspi_prepare_message,
1041 	.prepare_transfer = mx51_ecspi_prepare_transfer,
1042 	.trigger = mx51_ecspi_trigger,
1043 	.rx_available = mx51_ecspi_rx_available,
1044 	.reset = mx51_ecspi_reset,
1045 	.setup_wml = mx51_setup_wml,
1046 	.disable_dma = mx51_disable_dma,
1047 	.fifo_size = 64,
1048 	.has_dmamode = true,
1049 	.dynamic_burst = true,
1050 	.has_slavemode = true,
1051 	.disable = mx51_ecspi_disable,
1052 	.devtype = IMX51_ECSPI,
1053 };
1054 
1055 static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
1056 	.intctrl = mx51_ecspi_intctrl,
1057 	.prepare_message = mx51_ecspi_prepare_message,
1058 	.prepare_transfer = mx51_ecspi_prepare_transfer,
1059 	.trigger = mx51_ecspi_trigger,
1060 	.rx_available = mx51_ecspi_rx_available,
1061 	.disable_dma = mx51_disable_dma,
1062 	.reset = mx51_ecspi_reset,
1063 	.fifo_size = 64,
1064 	.has_dmamode = true,
1065 	.has_slavemode = true,
1066 	.disable = mx51_ecspi_disable,
1067 	.devtype = IMX53_ECSPI,
1068 };
1069 
1070 static struct spi_imx_devtype_data imx6ul_ecspi_devtype_data = {
1071 	.intctrl = mx51_ecspi_intctrl,
1072 	.prepare_message = mx51_ecspi_prepare_message,
1073 	.prepare_transfer = mx51_ecspi_prepare_transfer,
1074 	.trigger = mx51_ecspi_trigger,
1075 	.rx_available = mx51_ecspi_rx_available,
1076 	.reset = mx51_ecspi_reset,
1077 	.setup_wml = mx51_setup_wml,
1078 	.fifo_size = 64,
1079 	.has_dmamode = true,
1080 	.dynamic_burst = true,
1081 	.has_slavemode = true,
1082 	.tx_glitch_fixed = true,
1083 	.disable = mx51_ecspi_disable,
1084 	.devtype = IMX51_ECSPI,
1085 };
1086 
1087 static const struct of_device_id spi_imx_dt_ids[] = {
1088 	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
1089 	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
1090 	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
1091 	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
1092 	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
1093 	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
1094 	{ .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
1095 	{ .compatible = "fsl,imx6ul-ecspi", .data = &imx6ul_ecspi_devtype_data, },
1096 	{ /* sentinel */ }
1097 };
1098 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
1099 
1100 static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
1101 {
1102 	u32 ctrl;
1103 
1104 	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
1105 	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
1106 	ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
1107 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
1108 }
1109 
1110 static void spi_imx_push(struct spi_imx_data *spi_imx)
1111 {
1112 	unsigned int burst_len;
1113 
1114 	/*
1115 	 * Reload the FIFO when the remaining bytes to be transferred in the
1116 	 * current burst is 0. This only applies when bits_per_word is a
1117 	 * multiple of 8.
1118 	 */
1119 	if (!spi_imx->remainder) {
1120 		if (spi_imx->dynamic_burst) {
1121 
1122 			/* We need to deal unaligned data first */
1123 			burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
1124 
1125 			if (!burst_len)
1126 				burst_len = MX51_ECSPI_CTRL_MAX_BURST;
1127 
1128 			spi_imx_set_burst_len(spi_imx, burst_len * 8);
1129 
1130 			spi_imx->remainder = burst_len;
1131 		} else {
1132 			spi_imx->remainder = spi_imx_bytes_per_word(spi_imx->bits_per_word);
1133 		}
1134 	}
1135 
1136 	while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
1137 		if (!spi_imx->count)
1138 			break;
1139 		if (spi_imx->dynamic_burst &&
1140 		    spi_imx->txfifo >= DIV_ROUND_UP(spi_imx->remainder, 4))
1141 			break;
1142 		spi_imx->tx(spi_imx);
1143 		spi_imx->txfifo++;
1144 	}
1145 
1146 	if (!spi_imx->slave_mode)
1147 		spi_imx->devtype_data->trigger(spi_imx);
1148 }
1149 
1150 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
1151 {
1152 	struct spi_imx_data *spi_imx = dev_id;
1153 
1154 	while (spi_imx->txfifo &&
1155 	       spi_imx->devtype_data->rx_available(spi_imx)) {
1156 		spi_imx->rx(spi_imx);
1157 		spi_imx->txfifo--;
1158 	}
1159 
1160 	if (spi_imx->count) {
1161 		spi_imx_push(spi_imx);
1162 		return IRQ_HANDLED;
1163 	}
1164 
1165 	if (spi_imx->txfifo) {
1166 		/* No data left to push, but still waiting for rx data,
1167 		 * enable receive data available interrupt.
1168 		 */
1169 		spi_imx->devtype_data->intctrl(
1170 				spi_imx, MXC_INT_RR);
1171 		return IRQ_HANDLED;
1172 	}
1173 
1174 	spi_imx->devtype_data->intctrl(spi_imx, 0);
1175 	complete(&spi_imx->xfer_done);
1176 
1177 	return IRQ_HANDLED;
1178 }
1179 
1180 static int spi_imx_dma_configure(struct spi_controller *controller)
1181 {
1182 	int ret;
1183 	enum dma_slave_buswidth buswidth;
1184 	struct dma_slave_config rx = {}, tx = {};
1185 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1186 
1187 	switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
1188 	case 4:
1189 		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
1190 		break;
1191 	case 2:
1192 		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
1193 		break;
1194 	case 1:
1195 		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
1196 		break;
1197 	default:
1198 		return -EINVAL;
1199 	}
1200 
1201 	tx.direction = DMA_MEM_TO_DEV;
1202 	tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
1203 	tx.dst_addr_width = buswidth;
1204 	tx.dst_maxburst = spi_imx->wml;
1205 	ret = dmaengine_slave_config(controller->dma_tx, &tx);
1206 	if (ret) {
1207 		dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
1208 		return ret;
1209 	}
1210 
1211 	rx.direction = DMA_DEV_TO_MEM;
1212 	rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
1213 	rx.src_addr_width = buswidth;
1214 	rx.src_maxburst = spi_imx->wml;
1215 	ret = dmaengine_slave_config(controller->dma_rx, &rx);
1216 	if (ret) {
1217 		dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
1218 		return ret;
1219 	}
1220 
1221 	return 0;
1222 }
1223 
1224 static int spi_imx_setupxfer(struct spi_device *spi,
1225 				 struct spi_transfer *t)
1226 {
1227 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1228 
1229 	if (!t)
1230 		return 0;
1231 
1232 	if (!t->speed_hz) {
1233 		if (!spi->max_speed_hz) {
1234 			dev_err(&spi->dev, "no speed_hz provided!\n");
1235 			return -EINVAL;
1236 		}
1237 		dev_dbg(&spi->dev, "using spi->max_speed_hz!\n");
1238 		spi_imx->spi_bus_clk = spi->max_speed_hz;
1239 	} else
1240 		spi_imx->spi_bus_clk = t->speed_hz;
1241 
1242 	spi_imx->bits_per_word = t->bits_per_word;
1243 
1244 	/*
1245 	 * Initialize the functions for transfer. To transfer non byte-aligned
1246 	 * words, we have to use multiple word-size bursts, we can't use
1247 	 * dynamic_burst in that case.
1248 	 */
1249 	if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode &&
1250 	    !(spi->mode & SPI_CS_WORD) &&
1251 	    (spi_imx->bits_per_word == 8 ||
1252 	    spi_imx->bits_per_word == 16 ||
1253 	    spi_imx->bits_per_word == 32)) {
1254 
1255 		spi_imx->rx = spi_imx_buf_rx_swap;
1256 		spi_imx->tx = spi_imx_buf_tx_swap;
1257 		spi_imx->dynamic_burst = 1;
1258 
1259 	} else {
1260 		if (spi_imx->bits_per_word <= 8) {
1261 			spi_imx->rx = spi_imx_buf_rx_u8;
1262 			spi_imx->tx = spi_imx_buf_tx_u8;
1263 		} else if (spi_imx->bits_per_word <= 16) {
1264 			spi_imx->rx = spi_imx_buf_rx_u16;
1265 			spi_imx->tx = spi_imx_buf_tx_u16;
1266 		} else {
1267 			spi_imx->rx = spi_imx_buf_rx_u32;
1268 			spi_imx->tx = spi_imx_buf_tx_u32;
1269 		}
1270 		spi_imx->dynamic_burst = 0;
1271 	}
1272 
1273 	if (spi_imx_can_dma(spi_imx->controller, spi, t))
1274 		spi_imx->usedma = true;
1275 	else
1276 		spi_imx->usedma = false;
1277 
1278 	spi_imx->rx_only = ((t->tx_buf == NULL)
1279 			|| (t->tx_buf == spi->controller->dummy_tx));
1280 
1281 	if (is_imx53_ecspi(spi_imx) && spi_imx->slave_mode) {
1282 		spi_imx->rx = mx53_ecspi_rx_slave;
1283 		spi_imx->tx = mx53_ecspi_tx_slave;
1284 		spi_imx->slave_burst = t->len;
1285 	}
1286 
1287 	spi_imx->devtype_data->prepare_transfer(spi_imx, spi);
1288 
1289 	return 0;
1290 }
1291 
1292 static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
1293 {
1294 	struct spi_controller *controller = spi_imx->controller;
1295 
1296 	if (controller->dma_rx) {
1297 		dma_release_channel(controller->dma_rx);
1298 		controller->dma_rx = NULL;
1299 	}
1300 
1301 	if (controller->dma_tx) {
1302 		dma_release_channel(controller->dma_tx);
1303 		controller->dma_tx = NULL;
1304 	}
1305 }
1306 
1307 static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
1308 			     struct spi_controller *controller)
1309 {
1310 	int ret;
1311 
1312 	spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
1313 
1314 	/* Prepare for TX DMA: */
1315 	controller->dma_tx = dma_request_chan(dev, "tx");
1316 	if (IS_ERR(controller->dma_tx)) {
1317 		ret = PTR_ERR(controller->dma_tx);
1318 		dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
1319 		controller->dma_tx = NULL;
1320 		goto err;
1321 	}
1322 
1323 	/* Prepare for RX : */
1324 	controller->dma_rx = dma_request_chan(dev, "rx");
1325 	if (IS_ERR(controller->dma_rx)) {
1326 		ret = PTR_ERR(controller->dma_rx);
1327 		dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
1328 		controller->dma_rx = NULL;
1329 		goto err;
1330 	}
1331 
1332 	init_completion(&spi_imx->dma_rx_completion);
1333 	init_completion(&spi_imx->dma_tx_completion);
1334 	controller->can_dma = spi_imx_can_dma;
1335 	controller->max_dma_len = MAX_SDMA_BD_BYTES;
1336 	spi_imx->controller->flags = SPI_CONTROLLER_MUST_RX |
1337 					 SPI_CONTROLLER_MUST_TX;
1338 
1339 	return 0;
1340 err:
1341 	spi_imx_sdma_exit(spi_imx);
1342 	return ret;
1343 }
1344 
1345 static void spi_imx_dma_rx_callback(void *cookie)
1346 {
1347 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1348 
1349 	complete(&spi_imx->dma_rx_completion);
1350 }
1351 
1352 static void spi_imx_dma_tx_callback(void *cookie)
1353 {
1354 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1355 
1356 	complete(&spi_imx->dma_tx_completion);
1357 }
1358 
1359 static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1360 {
1361 	unsigned long timeout = 0;
1362 
1363 	/* Time with actual data transfer and CS change delay related to HW */
1364 	timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1365 
1366 	/* Add extra second for scheduler related activities */
1367 	timeout += 1;
1368 
1369 	/* Double calculated timeout */
1370 	return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1371 }
1372 
1373 static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1374 				struct spi_transfer *transfer)
1375 {
1376 	struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1377 	unsigned long transfer_timeout;
1378 	unsigned long timeout;
1379 	struct spi_controller *controller = spi_imx->controller;
1380 	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1381 	struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
1382 	unsigned int bytes_per_word, i;
1383 	int ret;
1384 
1385 	/* Get the right burst length from the last sg to ensure no tail data */
1386 	bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
1387 	for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
1388 		if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
1389 			break;
1390 	}
1391 	/* Use 1 as wml in case no available burst length got */
1392 	if (i == 0)
1393 		i = 1;
1394 
1395 	spi_imx->wml =  i;
1396 
1397 	ret = spi_imx_dma_configure(controller);
1398 	if (ret)
1399 		goto dma_failure_no_start;
1400 
1401 	if (!spi_imx->devtype_data->setup_wml) {
1402 		dev_err(spi_imx->dev, "No setup_wml()?\n");
1403 		ret = -EINVAL;
1404 		goto dma_failure_no_start;
1405 	}
1406 	spi_imx->devtype_data->setup_wml(spi_imx);
1407 
1408 	/*
1409 	 * The TX DMA setup starts the transfer, so make sure RX is configured
1410 	 * before TX.
1411 	 */
1412 	desc_rx = dmaengine_prep_slave_sg(controller->dma_rx,
1413 				rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1414 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1415 	if (!desc_rx) {
1416 		ret = -EINVAL;
1417 		goto dma_failure_no_start;
1418 	}
1419 
1420 	desc_rx->callback = spi_imx_dma_rx_callback;
1421 	desc_rx->callback_param = (void *)spi_imx;
1422 	dmaengine_submit(desc_rx);
1423 	reinit_completion(&spi_imx->dma_rx_completion);
1424 	dma_async_issue_pending(controller->dma_rx);
1425 
1426 	desc_tx = dmaengine_prep_slave_sg(controller->dma_tx,
1427 				tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1428 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1429 	if (!desc_tx) {
1430 		dmaengine_terminate_all(controller->dma_tx);
1431 		dmaengine_terminate_all(controller->dma_rx);
1432 		return -EINVAL;
1433 	}
1434 
1435 	desc_tx->callback = spi_imx_dma_tx_callback;
1436 	desc_tx->callback_param = (void *)spi_imx;
1437 	dmaengine_submit(desc_tx);
1438 	reinit_completion(&spi_imx->dma_tx_completion);
1439 	dma_async_issue_pending(controller->dma_tx);
1440 
1441 	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1442 
1443 	/* Wait SDMA to finish the data transfer.*/
1444 	timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1445 						transfer_timeout);
1446 	if (!timeout) {
1447 		dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1448 		dmaengine_terminate_all(controller->dma_tx);
1449 		dmaengine_terminate_all(controller->dma_rx);
1450 		return -ETIMEDOUT;
1451 	}
1452 
1453 	timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1454 					      transfer_timeout);
1455 	if (!timeout) {
1456 		dev_err(&controller->dev, "I/O Error in DMA RX\n");
1457 		spi_imx->devtype_data->reset(spi_imx);
1458 		dmaengine_terminate_all(controller->dma_rx);
1459 		return -ETIMEDOUT;
1460 	}
1461 
1462 	return 0;
1463 /* fallback to pio */
1464 dma_failure_no_start:
1465 	transfer->error |= SPI_TRANS_FAIL_NO_START;
1466 	return ret;
1467 }
1468 
1469 static int spi_imx_pio_transfer(struct spi_device *spi,
1470 				struct spi_transfer *transfer)
1471 {
1472 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1473 	unsigned long transfer_timeout;
1474 	unsigned long timeout;
1475 
1476 	spi_imx->tx_buf = transfer->tx_buf;
1477 	spi_imx->rx_buf = transfer->rx_buf;
1478 	spi_imx->count = transfer->len;
1479 	spi_imx->txfifo = 0;
1480 	spi_imx->remainder = 0;
1481 
1482 	reinit_completion(&spi_imx->xfer_done);
1483 
1484 	spi_imx_push(spi_imx);
1485 
1486 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1487 
1488 	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1489 
1490 	timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
1491 					      transfer_timeout);
1492 	if (!timeout) {
1493 		dev_err(&spi->dev, "I/O Error in PIO\n");
1494 		spi_imx->devtype_data->reset(spi_imx);
1495 		return -ETIMEDOUT;
1496 	}
1497 
1498 	return 0;
1499 }
1500 
1501 static int spi_imx_poll_transfer(struct spi_device *spi,
1502 				 struct spi_transfer *transfer)
1503 {
1504 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1505 	unsigned long timeout;
1506 
1507 	spi_imx->tx_buf = transfer->tx_buf;
1508 	spi_imx->rx_buf = transfer->rx_buf;
1509 	spi_imx->count = transfer->len;
1510 	spi_imx->txfifo = 0;
1511 	spi_imx->remainder = 0;
1512 
1513 	/* fill in the fifo before timeout calculations if we are
1514 	 * interrupted here, then the data is getting transferred by
1515 	 * the HW while we are interrupted
1516 	 */
1517 	spi_imx_push(spi_imx);
1518 
1519 	timeout = spi_imx_calculate_timeout(spi_imx, transfer->len) + jiffies;
1520 	while (spi_imx->txfifo) {
1521 		/* RX */
1522 		while (spi_imx->txfifo &&
1523 		       spi_imx->devtype_data->rx_available(spi_imx)) {
1524 			spi_imx->rx(spi_imx);
1525 			spi_imx->txfifo--;
1526 		}
1527 
1528 		/* TX */
1529 		if (spi_imx->count) {
1530 			spi_imx_push(spi_imx);
1531 			continue;
1532 		}
1533 
1534 		if (spi_imx->txfifo &&
1535 		    time_after(jiffies, timeout)) {
1536 
1537 			dev_err_ratelimited(&spi->dev,
1538 					    "timeout period reached: jiffies: %lu- falling back to interrupt mode\n",
1539 					    jiffies - timeout);
1540 
1541 			/* fall back to interrupt mode */
1542 			return spi_imx_pio_transfer(spi, transfer);
1543 		}
1544 	}
1545 
1546 	return 0;
1547 }
1548 
1549 static int spi_imx_pio_transfer_slave(struct spi_device *spi,
1550 				      struct spi_transfer *transfer)
1551 {
1552 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1553 	int ret = 0;
1554 
1555 	if (is_imx53_ecspi(spi_imx) &&
1556 	    transfer->len > MX53_MAX_TRANSFER_BYTES) {
1557 		dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
1558 			MX53_MAX_TRANSFER_BYTES);
1559 		return -EMSGSIZE;
1560 	}
1561 
1562 	spi_imx->tx_buf = transfer->tx_buf;
1563 	spi_imx->rx_buf = transfer->rx_buf;
1564 	spi_imx->count = transfer->len;
1565 	spi_imx->txfifo = 0;
1566 	spi_imx->remainder = 0;
1567 
1568 	reinit_completion(&spi_imx->xfer_done);
1569 	spi_imx->slave_aborted = false;
1570 
1571 	spi_imx_push(spi_imx);
1572 
1573 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
1574 
1575 	if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
1576 	    spi_imx->slave_aborted) {
1577 		dev_dbg(&spi->dev, "interrupted\n");
1578 		ret = -EINTR;
1579 	}
1580 
1581 	/* ecspi has a HW issue when works in Slave mode,
1582 	 * after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
1583 	 * ECSPI_TXDATA keeps shift out the last word data,
1584 	 * so we have to disable ECSPI when in slave mode after the
1585 	 * transfer completes
1586 	 */
1587 	if (spi_imx->devtype_data->disable)
1588 		spi_imx->devtype_data->disable(spi_imx);
1589 
1590 	return ret;
1591 }
1592 
1593 static int spi_imx_transfer_one(struct spi_controller *controller,
1594 				struct spi_device *spi,
1595 				struct spi_transfer *transfer)
1596 {
1597 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1598 	unsigned long hz_per_byte, byte_limit;
1599 
1600 	spi_imx_setupxfer(spi, transfer);
1601 	transfer->effective_speed_hz = spi_imx->spi_bus_clk;
1602 
1603 	/* flush rxfifo before transfer */
1604 	while (spi_imx->devtype_data->rx_available(spi_imx))
1605 		readl(spi_imx->base + MXC_CSPIRXDATA);
1606 
1607 	if (spi_imx->slave_mode)
1608 		return spi_imx_pio_transfer_slave(spi, transfer);
1609 
1610 	/*
1611 	 * Calculate the estimated time in us the transfer runs. Find
1612 	 * the number of Hz per byte per polling limit.
1613 	 */
1614 	hz_per_byte = polling_limit_us ? ((8 + 4) * USEC_PER_SEC) / polling_limit_us : 0;
1615 	byte_limit = hz_per_byte ? transfer->effective_speed_hz / hz_per_byte : 1;
1616 
1617 	/* run in polling mode for short transfers */
1618 	if (transfer->len < byte_limit)
1619 		return spi_imx_poll_transfer(spi, transfer);
1620 
1621 	if (spi_imx->usedma)
1622 		return spi_imx_dma_transfer(spi_imx, transfer);
1623 
1624 	return spi_imx_pio_transfer(spi, transfer);
1625 }
1626 
1627 static int spi_imx_setup(struct spi_device *spi)
1628 {
1629 	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1630 		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1631 
1632 	return 0;
1633 }
1634 
1635 static void spi_imx_cleanup(struct spi_device *spi)
1636 {
1637 }
1638 
1639 static int
1640 spi_imx_prepare_message(struct spi_controller *controller, struct spi_message *msg)
1641 {
1642 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1643 	int ret;
1644 
1645 	ret = pm_runtime_resume_and_get(spi_imx->dev);
1646 	if (ret < 0) {
1647 		dev_err(spi_imx->dev, "failed to enable clock\n");
1648 		return ret;
1649 	}
1650 
1651 	ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
1652 	if (ret) {
1653 		pm_runtime_mark_last_busy(spi_imx->dev);
1654 		pm_runtime_put_autosuspend(spi_imx->dev);
1655 	}
1656 
1657 	return ret;
1658 }
1659 
1660 static int
1661 spi_imx_unprepare_message(struct spi_controller *controller, struct spi_message *msg)
1662 {
1663 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1664 
1665 	pm_runtime_mark_last_busy(spi_imx->dev);
1666 	pm_runtime_put_autosuspend(spi_imx->dev);
1667 	return 0;
1668 }
1669 
1670 static int spi_imx_slave_abort(struct spi_controller *controller)
1671 {
1672 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1673 
1674 	spi_imx->slave_aborted = true;
1675 	complete(&spi_imx->xfer_done);
1676 
1677 	return 0;
1678 }
1679 
1680 static int spi_imx_probe(struct platform_device *pdev)
1681 {
1682 	struct device_node *np = pdev->dev.of_node;
1683 	struct spi_controller *controller;
1684 	struct spi_imx_data *spi_imx;
1685 	struct resource *res;
1686 	int ret, irq, spi_drctl;
1687 	const struct spi_imx_devtype_data *devtype_data =
1688 			of_device_get_match_data(&pdev->dev);
1689 	bool slave_mode;
1690 	u32 val;
1691 
1692 	slave_mode = devtype_data->has_slavemode &&
1693 			of_property_read_bool(np, "spi-slave");
1694 	if (slave_mode)
1695 		controller = spi_alloc_slave(&pdev->dev,
1696 					     sizeof(struct spi_imx_data));
1697 	else
1698 		controller = spi_alloc_master(&pdev->dev,
1699 					      sizeof(struct spi_imx_data));
1700 	if (!controller)
1701 		return -ENOMEM;
1702 
1703 	ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
1704 	if ((ret < 0) || (spi_drctl >= 0x3)) {
1705 		/* '11' is reserved */
1706 		spi_drctl = 0;
1707 	}
1708 
1709 	platform_set_drvdata(pdev, controller);
1710 
1711 	controller->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1712 	controller->bus_num = np ? -1 : pdev->id;
1713 	controller->use_gpio_descriptors = true;
1714 
1715 	spi_imx = spi_controller_get_devdata(controller);
1716 	spi_imx->controller = controller;
1717 	spi_imx->dev = &pdev->dev;
1718 	spi_imx->slave_mode = slave_mode;
1719 
1720 	spi_imx->devtype_data = devtype_data;
1721 
1722 	/*
1723 	 * Get number of chip selects from device properties. This can be
1724 	 * coming from device tree or boardfiles, if it is not defined,
1725 	 * a default value of 3 chip selects will be used, as all the legacy
1726 	 * board files have <= 3 chip selects.
1727 	 */
1728 	if (!device_property_read_u32(&pdev->dev, "num-cs", &val))
1729 		controller->num_chipselect = val;
1730 	else
1731 		controller->num_chipselect = 3;
1732 
1733 	spi_imx->controller->transfer_one = spi_imx_transfer_one;
1734 	spi_imx->controller->setup = spi_imx_setup;
1735 	spi_imx->controller->cleanup = spi_imx_cleanup;
1736 	spi_imx->controller->prepare_message = spi_imx_prepare_message;
1737 	spi_imx->controller->unprepare_message = spi_imx_unprepare_message;
1738 	spi_imx->controller->slave_abort = spi_imx_slave_abort;
1739 	spi_imx->controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_NO_CS;
1740 
1741 	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
1742 	    is_imx53_ecspi(spi_imx))
1743 		spi_imx->controller->mode_bits |= SPI_LOOP | SPI_READY;
1744 
1745 	if (is_imx51_ecspi(spi_imx) || is_imx53_ecspi(spi_imx))
1746 		spi_imx->controller->mode_bits |= SPI_RX_CPHA_FLIP;
1747 
1748 	if (is_imx51_ecspi(spi_imx) &&
1749 	    device_property_read_u32(&pdev->dev, "cs-gpios", NULL))
1750 		/*
1751 		 * When using HW-CS implementing SPI_CS_WORD can be done by just
1752 		 * setting the burst length to the word size. This is
1753 		 * considerably faster than manually controlling the CS.
1754 		 */
1755 		spi_imx->controller->mode_bits |= SPI_CS_WORD;
1756 
1757 	spi_imx->spi_drctl = spi_drctl;
1758 
1759 	init_completion(&spi_imx->xfer_done);
1760 
1761 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1762 	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1763 	if (IS_ERR(spi_imx->base)) {
1764 		ret = PTR_ERR(spi_imx->base);
1765 		goto out_controller_put;
1766 	}
1767 	spi_imx->base_phys = res->start;
1768 
1769 	irq = platform_get_irq(pdev, 0);
1770 	if (irq < 0) {
1771 		ret = irq;
1772 		goto out_controller_put;
1773 	}
1774 
1775 	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1776 			       dev_name(&pdev->dev), spi_imx);
1777 	if (ret) {
1778 		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1779 		goto out_controller_put;
1780 	}
1781 
1782 	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1783 	if (IS_ERR(spi_imx->clk_ipg)) {
1784 		ret = PTR_ERR(spi_imx->clk_ipg);
1785 		goto out_controller_put;
1786 	}
1787 
1788 	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1789 	if (IS_ERR(spi_imx->clk_per)) {
1790 		ret = PTR_ERR(spi_imx->clk_per);
1791 		goto out_controller_put;
1792 	}
1793 
1794 	ret = clk_prepare_enable(spi_imx->clk_per);
1795 	if (ret)
1796 		goto out_controller_put;
1797 
1798 	ret = clk_prepare_enable(spi_imx->clk_ipg);
1799 	if (ret)
1800 		goto out_put_per;
1801 
1802 	pm_runtime_set_autosuspend_delay(spi_imx->dev, MXC_RPM_TIMEOUT);
1803 	pm_runtime_use_autosuspend(spi_imx->dev);
1804 	pm_runtime_get_noresume(spi_imx->dev);
1805 	pm_runtime_set_active(spi_imx->dev);
1806 	pm_runtime_enable(spi_imx->dev);
1807 
1808 	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1809 	/*
1810 	 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1811 	 * if validated on other chips.
1812 	 */
1813 	if (spi_imx->devtype_data->has_dmamode) {
1814 		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, controller);
1815 		if (ret == -EPROBE_DEFER)
1816 			goto out_runtime_pm_put;
1817 
1818 		if (ret < 0)
1819 			dev_dbg(&pdev->dev, "dma setup error %d, use pio\n",
1820 				ret);
1821 	}
1822 
1823 	spi_imx->devtype_data->reset(spi_imx);
1824 
1825 	spi_imx->devtype_data->intctrl(spi_imx, 0);
1826 
1827 	controller->dev.of_node = pdev->dev.of_node;
1828 	ret = spi_register_controller(controller);
1829 	if (ret) {
1830 		dev_err_probe(&pdev->dev, ret, "register controller failed\n");
1831 		goto out_register_controller;
1832 	}
1833 
1834 	pm_runtime_mark_last_busy(spi_imx->dev);
1835 	pm_runtime_put_autosuspend(spi_imx->dev);
1836 
1837 	return ret;
1838 
1839 out_register_controller:
1840 	if (spi_imx->devtype_data->has_dmamode)
1841 		spi_imx_sdma_exit(spi_imx);
1842 out_runtime_pm_put:
1843 	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1844 	pm_runtime_set_suspended(&pdev->dev);
1845 	pm_runtime_disable(spi_imx->dev);
1846 
1847 	clk_disable_unprepare(spi_imx->clk_ipg);
1848 out_put_per:
1849 	clk_disable_unprepare(spi_imx->clk_per);
1850 out_controller_put:
1851 	spi_controller_put(controller);
1852 
1853 	return ret;
1854 }
1855 
1856 static int spi_imx_remove(struct platform_device *pdev)
1857 {
1858 	struct spi_controller *controller = platform_get_drvdata(pdev);
1859 	struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1860 	int ret;
1861 
1862 	spi_unregister_controller(controller);
1863 
1864 	ret = pm_runtime_resume_and_get(spi_imx->dev);
1865 	if (ret < 0) {
1866 		dev_err(spi_imx->dev, "failed to enable clock\n");
1867 		return ret;
1868 	}
1869 
1870 	writel(0, spi_imx->base + MXC_CSPICTRL);
1871 
1872 	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1873 	pm_runtime_put_sync(spi_imx->dev);
1874 	pm_runtime_disable(spi_imx->dev);
1875 
1876 	spi_imx_sdma_exit(spi_imx);
1877 
1878 	return 0;
1879 }
1880 
1881 static int __maybe_unused spi_imx_runtime_resume(struct device *dev)
1882 {
1883 	struct spi_controller *controller = dev_get_drvdata(dev);
1884 	struct spi_imx_data *spi_imx;
1885 	int ret;
1886 
1887 	spi_imx = spi_controller_get_devdata(controller);
1888 
1889 	ret = clk_prepare_enable(spi_imx->clk_per);
1890 	if (ret)
1891 		return ret;
1892 
1893 	ret = clk_prepare_enable(spi_imx->clk_ipg);
1894 	if (ret) {
1895 		clk_disable_unprepare(spi_imx->clk_per);
1896 		return ret;
1897 	}
1898 
1899 	return 0;
1900 }
1901 
1902 static int __maybe_unused spi_imx_runtime_suspend(struct device *dev)
1903 {
1904 	struct spi_controller *controller = dev_get_drvdata(dev);
1905 	struct spi_imx_data *spi_imx;
1906 
1907 	spi_imx = spi_controller_get_devdata(controller);
1908 
1909 	clk_disable_unprepare(spi_imx->clk_per);
1910 	clk_disable_unprepare(spi_imx->clk_ipg);
1911 
1912 	return 0;
1913 }
1914 
1915 static int __maybe_unused spi_imx_suspend(struct device *dev)
1916 {
1917 	pinctrl_pm_select_sleep_state(dev);
1918 	return 0;
1919 }
1920 
1921 static int __maybe_unused spi_imx_resume(struct device *dev)
1922 {
1923 	pinctrl_pm_select_default_state(dev);
1924 	return 0;
1925 }
1926 
1927 static const struct dev_pm_ops imx_spi_pm = {
1928 	SET_RUNTIME_PM_OPS(spi_imx_runtime_suspend,
1929 				spi_imx_runtime_resume, NULL)
1930 	SET_SYSTEM_SLEEP_PM_OPS(spi_imx_suspend, spi_imx_resume)
1931 };
1932 
1933 static struct platform_driver spi_imx_driver = {
1934 	.driver = {
1935 		   .name = DRIVER_NAME,
1936 		   .of_match_table = spi_imx_dt_ids,
1937 		   .pm = &imx_spi_pm,
1938 	},
1939 	.probe = spi_imx_probe,
1940 	.remove = spi_imx_remove,
1941 };
1942 module_platform_driver(spi_imx_driver);
1943 
1944 MODULE_DESCRIPTION("i.MX SPI Controller driver");
1945 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1946 MODULE_LICENSE("GPL");
1947 MODULE_ALIAS("platform:" DRIVER_NAME);
1948