xref: /OK3568_Linux_fs/kernel/drivers/spi/spi-imx.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1 // SPDX-License-Identifier: GPL-2.0+
2 // Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
3 // Copyright (C) 2008 Juergen Beisert
4 
5 #include <linux/clk.h>
6 #include <linux/completion.h>
7 #include <linux/delay.h>
8 #include <linux/dmaengine.h>
9 #include <linux/dma-mapping.h>
10 #include <linux/err.h>
11 #include <linux/interrupt.h>
12 #include <linux/io.h>
13 #include <linux/irq.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/pinctrl/consumer.h>
17 #include <linux/platform_device.h>
18 #include <linux/pm_runtime.h>
19 #include <linux/slab.h>
20 #include <linux/spi/spi.h>
21 #include <linux/spi/spi_bitbang.h>
22 #include <linux/types.h>
23 #include <linux/of.h>
24 #include <linux/of_device.h>
25 #include <linux/property.h>
26 
27 #include <linux/platform_data/dma-imx.h>
28 
29 #define DRIVER_NAME "spi_imx"
30 
31 static bool use_dma = true;
32 module_param(use_dma, bool, 0644);
33 MODULE_PARM_DESC(use_dma, "Enable usage of DMA when available (default)");
34 
35 #define MXC_RPM_TIMEOUT		2000 /* 2000ms */
36 
37 #define MXC_CSPIRXDATA		0x00
38 #define MXC_CSPITXDATA		0x04
39 #define MXC_CSPICTRL		0x08
40 #define MXC_CSPIINT		0x0c
41 #define MXC_RESET		0x1c
42 
43 /* generic defines to abstract from the different register layouts */
44 #define MXC_INT_RR	(1 << 0) /* Receive data ready interrupt */
45 #define MXC_INT_TE	(1 << 1) /* Transmit FIFO empty interrupt */
46 #define MXC_INT_RDR	BIT(4) /* Receive date threshold interrupt */
47 
48 /* The maximum bytes that a sdma BD can transfer. */
49 #define MAX_SDMA_BD_BYTES (1 << 15)
50 #define MX51_ECSPI_CTRL_MAX_BURST	512
51 /* The maximum bytes that IMX53_ECSPI can transfer in slave mode.*/
52 #define MX53_MAX_TRANSFER_BYTES		512
53 
54 enum spi_imx_devtype {
55 	IMX1_CSPI,
56 	IMX21_CSPI,
57 	IMX27_CSPI,
58 	IMX31_CSPI,
59 	IMX35_CSPI,	/* CSPI on all i.mx except above */
60 	IMX51_ECSPI,	/* ECSPI on i.mx51 */
61 	IMX53_ECSPI,	/* ECSPI on i.mx53 and later */
62 };
63 
64 struct spi_imx_data;
65 
66 struct spi_imx_devtype_data {
67 	void (*intctrl)(struct spi_imx_data *, int);
68 	int (*prepare_message)(struct spi_imx_data *, struct spi_message *);
69 	int (*prepare_transfer)(struct spi_imx_data *, struct spi_device *);
70 	void (*trigger)(struct spi_imx_data *);
71 	int (*rx_available)(struct spi_imx_data *);
72 	void (*reset)(struct spi_imx_data *);
73 	void (*setup_wml)(struct spi_imx_data *);
74 	void (*disable)(struct spi_imx_data *);
75 	void (*disable_dma)(struct spi_imx_data *);
76 	bool has_dmamode;
77 	bool has_slavemode;
78 	unsigned int fifo_size;
79 	bool dynamic_burst;
80 	enum spi_imx_devtype devtype;
81 };
82 
83 struct spi_imx_data {
84 	struct spi_bitbang bitbang;
85 	struct device *dev;
86 
87 	struct completion xfer_done;
88 	void __iomem *base;
89 	unsigned long base_phys;
90 
91 	struct clk *clk_per;
92 	struct clk *clk_ipg;
93 	unsigned long spi_clk;
94 	unsigned int spi_bus_clk;
95 
96 	unsigned int bits_per_word;
97 	unsigned int spi_drctl;
98 
99 	unsigned int count, remainder;
100 	void (*tx)(struct spi_imx_data *);
101 	void (*rx)(struct spi_imx_data *);
102 	void *rx_buf;
103 	const void *tx_buf;
104 	unsigned int txfifo; /* number of words pushed in tx FIFO */
105 	unsigned int dynamic_burst;
106 
107 	/* Slave mode */
108 	bool slave_mode;
109 	bool slave_aborted;
110 	unsigned int slave_burst;
111 
112 	/* DMA */
113 	bool usedma;
114 	u32 wml;
115 	struct completion dma_rx_completion;
116 	struct completion dma_tx_completion;
117 
118 	const struct spi_imx_devtype_data *devtype_data;
119 };
120 
is_imx27_cspi(struct spi_imx_data * d)121 static inline int is_imx27_cspi(struct spi_imx_data *d)
122 {
123 	return d->devtype_data->devtype == IMX27_CSPI;
124 }
125 
is_imx35_cspi(struct spi_imx_data * d)126 static inline int is_imx35_cspi(struct spi_imx_data *d)
127 {
128 	return d->devtype_data->devtype == IMX35_CSPI;
129 }
130 
is_imx51_ecspi(struct spi_imx_data * d)131 static inline int is_imx51_ecspi(struct spi_imx_data *d)
132 {
133 	return d->devtype_data->devtype == IMX51_ECSPI;
134 }
135 
is_imx53_ecspi(struct spi_imx_data * d)136 static inline int is_imx53_ecspi(struct spi_imx_data *d)
137 {
138 	return d->devtype_data->devtype == IMX53_ECSPI;
139 }
140 
141 #define MXC_SPI_BUF_RX(type)						\
142 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
143 {									\
144 	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
145 									\
146 	if (spi_imx->rx_buf) {						\
147 		*(type *)spi_imx->rx_buf = val;				\
148 		spi_imx->rx_buf += sizeof(type);			\
149 	}								\
150 									\
151 	spi_imx->remainder -= sizeof(type);				\
152 }
153 
154 #define MXC_SPI_BUF_TX(type)						\
155 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
156 {									\
157 	type val = 0;							\
158 									\
159 	if (spi_imx->tx_buf) {						\
160 		val = *(type *)spi_imx->tx_buf;				\
161 		spi_imx->tx_buf += sizeof(type);			\
162 	}								\
163 									\
164 	spi_imx->count -= sizeof(type);					\
165 									\
166 	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
167 }
168 
169 MXC_SPI_BUF_RX(u8)
170 MXC_SPI_BUF_TX(u8)
171 MXC_SPI_BUF_RX(u16)
172 MXC_SPI_BUF_TX(u16)
173 MXC_SPI_BUF_RX(u32)
174 MXC_SPI_BUF_TX(u32)
175 
176 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
177  * (which is currently not the case in this driver)
178  */
179 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
180 	256, 384, 512, 768, 1024};
181 
182 /* MX21, MX27 */
spi_imx_clkdiv_1(unsigned int fin,unsigned int fspi,unsigned int max,unsigned int * fres)183 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
184 		unsigned int fspi, unsigned int max, unsigned int *fres)
185 {
186 	int i;
187 
188 	for (i = 2; i < max; i++)
189 		if (fspi * mxc_clkdivs[i] >= fin)
190 			break;
191 
192 	*fres = fin / mxc_clkdivs[i];
193 	return i;
194 }
195 
196 /* MX1, MX31, MX35, MX51 CSPI */
spi_imx_clkdiv_2(unsigned int fin,unsigned int fspi,unsigned int * fres)197 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
198 		unsigned int fspi, unsigned int *fres)
199 {
200 	int i, div = 4;
201 
202 	for (i = 0; i < 7; i++) {
203 		if (fspi * div >= fin)
204 			goto out;
205 		div <<= 1;
206 	}
207 
208 out:
209 	*fres = fin / div;
210 	return i;
211 }
212 
spi_imx_bytes_per_word(const int bits_per_word)213 static int spi_imx_bytes_per_word(const int bits_per_word)
214 {
215 	if (bits_per_word <= 8)
216 		return 1;
217 	else if (bits_per_word <= 16)
218 		return 2;
219 	else
220 		return 4;
221 }
222 
spi_imx_can_dma(struct spi_master * master,struct spi_device * spi,struct spi_transfer * transfer)223 static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
224 			 struct spi_transfer *transfer)
225 {
226 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
227 
228 	if (!use_dma || master->fallback)
229 		return false;
230 
231 	if (!master->dma_rx)
232 		return false;
233 
234 	if (spi_imx->slave_mode)
235 		return false;
236 
237 	if (transfer->len < spi_imx->devtype_data->fifo_size)
238 		return false;
239 
240 	spi_imx->dynamic_burst = 0;
241 
242 	return true;
243 }
244 
245 #define MX51_ECSPI_CTRL		0x08
246 #define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
247 #define MX51_ECSPI_CTRL_XCH		(1 <<  2)
248 #define MX51_ECSPI_CTRL_SMC		(1 << 3)
249 #define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
250 #define MX51_ECSPI_CTRL_DRCTL(drctl)	((drctl) << 16)
251 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
252 #define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
253 #define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
254 #define MX51_ECSPI_CTRL_BL_OFFSET	20
255 #define MX51_ECSPI_CTRL_BL_MASK		(0xfff << 20)
256 
257 #define MX51_ECSPI_CONFIG	0x0c
258 #define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
259 #define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
260 #define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
261 #define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
262 #define MX51_ECSPI_CONFIG_SCLKCTL(cs)	(1 << ((cs) + 20))
263 
264 #define MX51_ECSPI_INT		0x10
265 #define MX51_ECSPI_INT_TEEN		(1 <<  0)
266 #define MX51_ECSPI_INT_RREN		(1 <<  3)
267 #define MX51_ECSPI_INT_RDREN		(1 <<  4)
268 
269 #define MX51_ECSPI_DMA		0x14
270 #define MX51_ECSPI_DMA_TX_WML(wml)	((wml) & 0x3f)
271 #define MX51_ECSPI_DMA_RX_WML(wml)	(((wml) & 0x3f) << 16)
272 #define MX51_ECSPI_DMA_RXT_WML(wml)	(((wml) & 0x3f) << 24)
273 
274 #define MX51_ECSPI_DMA_TEDEN		(1 << 7)
275 #define MX51_ECSPI_DMA_RXDEN		(1 << 23)
276 #define MX51_ECSPI_DMA_RXTDEN		(1 << 31)
277 
278 #define MX51_ECSPI_STAT		0x18
279 #define MX51_ECSPI_STAT_RR		(1 <<  3)
280 
281 #define MX51_ECSPI_TESTREG	0x20
282 #define MX51_ECSPI_TESTREG_LBC	BIT(31)
283 
spi_imx_buf_rx_swap_u32(struct spi_imx_data * spi_imx)284 static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
285 {
286 	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
287 #ifdef __LITTLE_ENDIAN
288 	unsigned int bytes_per_word;
289 #endif
290 
291 	if (spi_imx->rx_buf) {
292 #ifdef __LITTLE_ENDIAN
293 		bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
294 		if (bytes_per_word == 1)
295 			val = cpu_to_be32(val);
296 		else if (bytes_per_word == 2)
297 			val = (val << 16) | (val >> 16);
298 #endif
299 		*(u32 *)spi_imx->rx_buf = val;
300 		spi_imx->rx_buf += sizeof(u32);
301 	}
302 
303 	spi_imx->remainder -= sizeof(u32);
304 }
305 
spi_imx_buf_rx_swap(struct spi_imx_data * spi_imx)306 static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
307 {
308 	int unaligned;
309 	u32 val;
310 
311 	unaligned = spi_imx->remainder % 4;
312 
313 	if (!unaligned) {
314 		spi_imx_buf_rx_swap_u32(spi_imx);
315 		return;
316 	}
317 
318 	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
319 		spi_imx_buf_rx_u16(spi_imx);
320 		return;
321 	}
322 
323 	val = readl(spi_imx->base + MXC_CSPIRXDATA);
324 
325 	while (unaligned--) {
326 		if (spi_imx->rx_buf) {
327 			*(u8 *)spi_imx->rx_buf = (val >> (8 * unaligned)) & 0xff;
328 			spi_imx->rx_buf++;
329 		}
330 		spi_imx->remainder--;
331 	}
332 }
333 
spi_imx_buf_tx_swap_u32(struct spi_imx_data * spi_imx)334 static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
335 {
336 	u32 val = 0;
337 #ifdef __LITTLE_ENDIAN
338 	unsigned int bytes_per_word;
339 #endif
340 
341 	if (spi_imx->tx_buf) {
342 		val = *(u32 *)spi_imx->tx_buf;
343 		spi_imx->tx_buf += sizeof(u32);
344 	}
345 
346 	spi_imx->count -= sizeof(u32);
347 #ifdef __LITTLE_ENDIAN
348 	bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
349 
350 	if (bytes_per_word == 1)
351 		val = cpu_to_be32(val);
352 	else if (bytes_per_word == 2)
353 		val = (val << 16) | (val >> 16);
354 #endif
355 	writel(val, spi_imx->base + MXC_CSPITXDATA);
356 }
357 
spi_imx_buf_tx_swap(struct spi_imx_data * spi_imx)358 static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
359 {
360 	int unaligned;
361 	u32 val = 0;
362 
363 	unaligned = spi_imx->count % 4;
364 
365 	if (!unaligned) {
366 		spi_imx_buf_tx_swap_u32(spi_imx);
367 		return;
368 	}
369 
370 	if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
371 		spi_imx_buf_tx_u16(spi_imx);
372 		return;
373 	}
374 
375 	while (unaligned--) {
376 		if (spi_imx->tx_buf) {
377 			val |= *(u8 *)spi_imx->tx_buf << (8 * unaligned);
378 			spi_imx->tx_buf++;
379 		}
380 		spi_imx->count--;
381 	}
382 
383 	writel(val, spi_imx->base + MXC_CSPITXDATA);
384 }
385 
mx53_ecspi_rx_slave(struct spi_imx_data * spi_imx)386 static void mx53_ecspi_rx_slave(struct spi_imx_data *spi_imx)
387 {
388 	u32 val = be32_to_cpu(readl(spi_imx->base + MXC_CSPIRXDATA));
389 
390 	if (spi_imx->rx_buf) {
391 		int n_bytes = spi_imx->slave_burst % sizeof(val);
392 
393 		if (!n_bytes)
394 			n_bytes = sizeof(val);
395 
396 		memcpy(spi_imx->rx_buf,
397 		       ((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
398 
399 		spi_imx->rx_buf += n_bytes;
400 		spi_imx->slave_burst -= n_bytes;
401 	}
402 
403 	spi_imx->remainder -= sizeof(u32);
404 }
405 
mx53_ecspi_tx_slave(struct spi_imx_data * spi_imx)406 static void mx53_ecspi_tx_slave(struct spi_imx_data *spi_imx)
407 {
408 	u32 val = 0;
409 	int n_bytes = spi_imx->count % sizeof(val);
410 
411 	if (!n_bytes)
412 		n_bytes = sizeof(val);
413 
414 	if (spi_imx->tx_buf) {
415 		memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
416 		       spi_imx->tx_buf, n_bytes);
417 		val = cpu_to_be32(val);
418 		spi_imx->tx_buf += n_bytes;
419 	}
420 
421 	spi_imx->count -= n_bytes;
422 
423 	writel(val, spi_imx->base + MXC_CSPITXDATA);
424 }
425 
426 /* MX51 eCSPI */
mx51_ecspi_clkdiv(struct spi_imx_data * spi_imx,unsigned int fspi,unsigned int * fres)427 static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
428 				      unsigned int fspi, unsigned int *fres)
429 {
430 	/*
431 	 * there are two 4-bit dividers, the pre-divider divides by
432 	 * $pre, the post-divider by 2^$post
433 	 */
434 	unsigned int pre, post;
435 	unsigned int fin = spi_imx->spi_clk;
436 
437 	fspi = min(fspi, fin);
438 
439 	post = fls(fin) - fls(fspi);
440 	if (fin > fspi << post)
441 		post++;
442 
443 	/* now we have: (fin <= fspi << post) with post being minimal */
444 
445 	post = max(4U, post) - 4;
446 	if (unlikely(post > 0xf)) {
447 		dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
448 				fspi, fin);
449 		return 0xff;
450 	}
451 
452 	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
453 
454 	dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
455 			__func__, fin, fspi, post, pre);
456 
457 	/* Resulting frequency for the SCLK line. */
458 	*fres = (fin / (pre + 1)) >> post;
459 
460 	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
461 		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
462 }
463 
mx51_ecspi_intctrl(struct spi_imx_data * spi_imx,int enable)464 static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
465 {
466 	unsigned val = 0;
467 
468 	if (enable & MXC_INT_TE)
469 		val |= MX51_ECSPI_INT_TEEN;
470 
471 	if (enable & MXC_INT_RR)
472 		val |= MX51_ECSPI_INT_RREN;
473 
474 	if (enable & MXC_INT_RDR)
475 		val |= MX51_ECSPI_INT_RDREN;
476 
477 	writel(val, spi_imx->base + MX51_ECSPI_INT);
478 }
479 
mx51_ecspi_trigger(struct spi_imx_data * spi_imx)480 static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
481 {
482 	u32 reg;
483 
484 	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
485 	reg |= MX51_ECSPI_CTRL_XCH;
486 	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
487 }
488 
mx51_disable_dma(struct spi_imx_data * spi_imx)489 static void mx51_disable_dma(struct spi_imx_data *spi_imx)
490 {
491 	writel(0, spi_imx->base + MX51_ECSPI_DMA);
492 }
493 
mx51_ecspi_disable(struct spi_imx_data * spi_imx)494 static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
495 {
496 	u32 ctrl;
497 
498 	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
499 	ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
500 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
501 }
502 
mx51_ecspi_prepare_message(struct spi_imx_data * spi_imx,struct spi_message * msg)503 static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
504 				      struct spi_message *msg)
505 {
506 	struct spi_device *spi = msg->spi;
507 	struct spi_transfer *xfer;
508 	u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
509 	u32 min_speed_hz = ~0U;
510 	u32 testreg, delay;
511 	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
512 
513 	/* set Master or Slave mode */
514 	if (spi_imx->slave_mode)
515 		ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
516 	else
517 		ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
518 
519 	/*
520 	 * Enable SPI_RDY handling (falling edge/level triggered).
521 	 */
522 	if (spi->mode & SPI_READY)
523 		ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
524 
525 	/* set chip select to use */
526 	ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
527 
528 	/*
529 	 * The ctrl register must be written first, with the EN bit set other
530 	 * registers must not be written to.
531 	 */
532 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
533 
534 	testreg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
535 	if (spi->mode & SPI_LOOP)
536 		testreg |= MX51_ECSPI_TESTREG_LBC;
537 	else
538 		testreg &= ~MX51_ECSPI_TESTREG_LBC;
539 	writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
540 
541 	/*
542 	 * eCSPI burst completion by Chip Select signal in Slave mode
543 	 * is not functional for imx53 Soc, config SPI burst completed when
544 	 * BURST_LENGTH + 1 bits are received
545 	 */
546 	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
547 		cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
548 	else
549 		cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
550 
551 	if (spi->mode & SPI_CPHA)
552 		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
553 	else
554 		cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
555 
556 	if (spi->mode & SPI_CPOL) {
557 		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
558 		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
559 	} else {
560 		cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
561 		cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
562 	}
563 
564 	if (spi->mode & SPI_CS_HIGH)
565 		cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
566 	else
567 		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
568 
569 	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
570 
571 	/*
572 	 * Wait until the changes in the configuration register CONFIGREG
573 	 * propagate into the hardware. It takes exactly one tick of the
574 	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
575 	 * effect of the delay it takes for the hardware to apply changes
576 	 * is noticable if the SCLK clock run very slow. In such a case, if
577 	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
578 	 * be asserted before the SCLK polarity changes, which would disrupt
579 	 * the SPI communication as the device on the other end would consider
580 	 * the change of SCLK polarity as a clock tick already.
581 	 *
582 	 * Because spi_imx->spi_bus_clk is only set in bitbang prepare_message
583 	 * callback, iterate over all the transfers in spi_message, find the
584 	 * one with lowest bus frequency, and use that bus frequency for the
585 	 * delay calculation. In case all transfers have speed_hz == 0, then
586 	 * min_speed_hz is ~0 and the resulting delay is zero.
587 	 */
588 	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
589 		if (!xfer->speed_hz)
590 			continue;
591 		min_speed_hz = min(xfer->speed_hz, min_speed_hz);
592 	}
593 
594 	delay = (2 * 1000000) / min_speed_hz;
595 	if (likely(delay < 10))	/* SCLK is faster than 100 kHz */
596 		udelay(delay);
597 	else			/* SCLK is _very_ slow */
598 		usleep_range(delay, delay + 10);
599 
600 	return 0;
601 }
602 
mx51_ecspi_prepare_transfer(struct spi_imx_data * spi_imx,struct spi_device * spi)603 static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
604 				       struct spi_device *spi)
605 {
606 	u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
607 	u32 clk;
608 
609 	/* Clear BL field and set the right value */
610 	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
611 	if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
612 		ctrl |= (spi_imx->slave_burst * 8 - 1)
613 			<< MX51_ECSPI_CTRL_BL_OFFSET;
614 	else
615 		ctrl |= (spi_imx->bits_per_word - 1)
616 			<< MX51_ECSPI_CTRL_BL_OFFSET;
617 
618 	/* set clock speed */
619 	ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
620 		  0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
621 	ctrl |= mx51_ecspi_clkdiv(spi_imx, spi_imx->spi_bus_clk, &clk);
622 	spi_imx->spi_bus_clk = clk;
623 
624 	if (spi_imx->usedma)
625 		ctrl |= MX51_ECSPI_CTRL_SMC;
626 
627 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
628 
629 	return 0;
630 }
631 
mx51_setup_wml(struct spi_imx_data * spi_imx)632 static void mx51_setup_wml(struct spi_imx_data *spi_imx)
633 {
634 	/*
635 	 * Configure the DMA register: setup the watermark
636 	 * and enable DMA request.
637 	 */
638 	writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) |
639 		MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
640 		MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
641 		MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
642 		MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
643 }
644 
mx51_ecspi_rx_available(struct spi_imx_data * spi_imx)645 static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
646 {
647 	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
648 }
649 
mx51_ecspi_reset(struct spi_imx_data * spi_imx)650 static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
651 {
652 	/* drain receive buffer */
653 	while (mx51_ecspi_rx_available(spi_imx))
654 		readl(spi_imx->base + MXC_CSPIRXDATA);
655 }
656 
657 #define MX31_INTREG_TEEN	(1 << 0)
658 #define MX31_INTREG_RREN	(1 << 3)
659 
660 #define MX31_CSPICTRL_ENABLE	(1 << 0)
661 #define MX31_CSPICTRL_MASTER	(1 << 1)
662 #define MX31_CSPICTRL_XCH	(1 << 2)
663 #define MX31_CSPICTRL_SMC	(1 << 3)
664 #define MX31_CSPICTRL_POL	(1 << 4)
665 #define MX31_CSPICTRL_PHA	(1 << 5)
666 #define MX31_CSPICTRL_SSCTL	(1 << 6)
667 #define MX31_CSPICTRL_SSPOL	(1 << 7)
668 #define MX31_CSPICTRL_BC_SHIFT	8
669 #define MX35_CSPICTRL_BL_SHIFT	20
670 #define MX31_CSPICTRL_CS_SHIFT	24
671 #define MX35_CSPICTRL_CS_SHIFT	12
672 #define MX31_CSPICTRL_DR_SHIFT	16
673 
674 #define MX31_CSPI_DMAREG	0x10
675 #define MX31_DMAREG_RH_DEN	(1<<4)
676 #define MX31_DMAREG_TH_DEN	(1<<1)
677 
678 #define MX31_CSPISTATUS		0x14
679 #define MX31_STATUS_RR		(1 << 3)
680 
681 #define MX31_CSPI_TESTREG	0x1C
682 #define MX31_TEST_LBC		(1 << 14)
683 
684 /* These functions also work for the i.MX35, but be aware that
685  * the i.MX35 has a slightly different register layout for bits
686  * we do not use here.
687  */
mx31_intctrl(struct spi_imx_data * spi_imx,int enable)688 static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
689 {
690 	unsigned int val = 0;
691 
692 	if (enable & MXC_INT_TE)
693 		val |= MX31_INTREG_TEEN;
694 	if (enable & MXC_INT_RR)
695 		val |= MX31_INTREG_RREN;
696 
697 	writel(val, spi_imx->base + MXC_CSPIINT);
698 }
699 
mx31_trigger(struct spi_imx_data * spi_imx)700 static void mx31_trigger(struct spi_imx_data *spi_imx)
701 {
702 	unsigned int reg;
703 
704 	reg = readl(spi_imx->base + MXC_CSPICTRL);
705 	reg |= MX31_CSPICTRL_XCH;
706 	writel(reg, spi_imx->base + MXC_CSPICTRL);
707 }
708 
mx31_prepare_message(struct spi_imx_data * spi_imx,struct spi_message * msg)709 static int mx31_prepare_message(struct spi_imx_data *spi_imx,
710 				struct spi_message *msg)
711 {
712 	return 0;
713 }
714 
mx31_prepare_transfer(struct spi_imx_data * spi_imx,struct spi_device * spi)715 static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
716 				 struct spi_device *spi)
717 {
718 	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
719 	unsigned int clk;
720 
721 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
722 		MX31_CSPICTRL_DR_SHIFT;
723 	spi_imx->spi_bus_clk = clk;
724 
725 	if (is_imx35_cspi(spi_imx)) {
726 		reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
727 		reg |= MX31_CSPICTRL_SSCTL;
728 	} else {
729 		reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
730 	}
731 
732 	if (spi->mode & SPI_CPHA)
733 		reg |= MX31_CSPICTRL_PHA;
734 	if (spi->mode & SPI_CPOL)
735 		reg |= MX31_CSPICTRL_POL;
736 	if (spi->mode & SPI_CS_HIGH)
737 		reg |= MX31_CSPICTRL_SSPOL;
738 	if (!spi->cs_gpiod)
739 		reg |= (spi->chip_select) <<
740 			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
741 						  MX31_CSPICTRL_CS_SHIFT);
742 
743 	if (spi_imx->usedma)
744 		reg |= MX31_CSPICTRL_SMC;
745 
746 	writel(reg, spi_imx->base + MXC_CSPICTRL);
747 
748 	reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
749 	if (spi->mode & SPI_LOOP)
750 		reg |= MX31_TEST_LBC;
751 	else
752 		reg &= ~MX31_TEST_LBC;
753 	writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
754 
755 	if (spi_imx->usedma) {
756 		/*
757 		 * configure DMA requests when RXFIFO is half full and
758 		 * when TXFIFO is half empty
759 		 */
760 		writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
761 			spi_imx->base + MX31_CSPI_DMAREG);
762 	}
763 
764 	return 0;
765 }
766 
mx31_rx_available(struct spi_imx_data * spi_imx)767 static int mx31_rx_available(struct spi_imx_data *spi_imx)
768 {
769 	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
770 }
771 
mx31_reset(struct spi_imx_data * spi_imx)772 static void mx31_reset(struct spi_imx_data *spi_imx)
773 {
774 	/* drain receive buffer */
775 	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
776 		readl(spi_imx->base + MXC_CSPIRXDATA);
777 }
778 
779 #define MX21_INTREG_RR		(1 << 4)
780 #define MX21_INTREG_TEEN	(1 << 9)
781 #define MX21_INTREG_RREN	(1 << 13)
782 
783 #define MX21_CSPICTRL_POL	(1 << 5)
784 #define MX21_CSPICTRL_PHA	(1 << 6)
785 #define MX21_CSPICTRL_SSPOL	(1 << 8)
786 #define MX21_CSPICTRL_XCH	(1 << 9)
787 #define MX21_CSPICTRL_ENABLE	(1 << 10)
788 #define MX21_CSPICTRL_MASTER	(1 << 11)
789 #define MX21_CSPICTRL_DR_SHIFT	14
790 #define MX21_CSPICTRL_CS_SHIFT	19
791 
mx21_intctrl(struct spi_imx_data * spi_imx,int enable)792 static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
793 {
794 	unsigned int val = 0;
795 
796 	if (enable & MXC_INT_TE)
797 		val |= MX21_INTREG_TEEN;
798 	if (enable & MXC_INT_RR)
799 		val |= MX21_INTREG_RREN;
800 
801 	writel(val, spi_imx->base + MXC_CSPIINT);
802 }
803 
mx21_trigger(struct spi_imx_data * spi_imx)804 static void mx21_trigger(struct spi_imx_data *spi_imx)
805 {
806 	unsigned int reg;
807 
808 	reg = readl(spi_imx->base + MXC_CSPICTRL);
809 	reg |= MX21_CSPICTRL_XCH;
810 	writel(reg, spi_imx->base + MXC_CSPICTRL);
811 }
812 
mx21_prepare_message(struct spi_imx_data * spi_imx,struct spi_message * msg)813 static int mx21_prepare_message(struct spi_imx_data *spi_imx,
814 				struct spi_message *msg)
815 {
816 	return 0;
817 }
818 
mx21_prepare_transfer(struct spi_imx_data * spi_imx,struct spi_device * spi)819 static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
820 				 struct spi_device *spi)
821 {
822 	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
823 	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
824 	unsigned int clk;
825 
826 	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, spi_imx->spi_bus_clk, max, &clk)
827 		<< MX21_CSPICTRL_DR_SHIFT;
828 	spi_imx->spi_bus_clk = clk;
829 
830 	reg |= spi_imx->bits_per_word - 1;
831 
832 	if (spi->mode & SPI_CPHA)
833 		reg |= MX21_CSPICTRL_PHA;
834 	if (spi->mode & SPI_CPOL)
835 		reg |= MX21_CSPICTRL_POL;
836 	if (spi->mode & SPI_CS_HIGH)
837 		reg |= MX21_CSPICTRL_SSPOL;
838 	if (!spi->cs_gpiod)
839 		reg |= spi->chip_select << MX21_CSPICTRL_CS_SHIFT;
840 
841 	writel(reg, spi_imx->base + MXC_CSPICTRL);
842 
843 	return 0;
844 }
845 
mx21_rx_available(struct spi_imx_data * spi_imx)846 static int mx21_rx_available(struct spi_imx_data *spi_imx)
847 {
848 	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
849 }
850 
mx21_reset(struct spi_imx_data * spi_imx)851 static void mx21_reset(struct spi_imx_data *spi_imx)
852 {
853 	writel(1, spi_imx->base + MXC_RESET);
854 }
855 
856 #define MX1_INTREG_RR		(1 << 3)
857 #define MX1_INTREG_TEEN		(1 << 8)
858 #define MX1_INTREG_RREN		(1 << 11)
859 
860 #define MX1_CSPICTRL_POL	(1 << 4)
861 #define MX1_CSPICTRL_PHA	(1 << 5)
862 #define MX1_CSPICTRL_XCH	(1 << 8)
863 #define MX1_CSPICTRL_ENABLE	(1 << 9)
864 #define MX1_CSPICTRL_MASTER	(1 << 10)
865 #define MX1_CSPICTRL_DR_SHIFT	13
866 
mx1_intctrl(struct spi_imx_data * spi_imx,int enable)867 static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
868 {
869 	unsigned int val = 0;
870 
871 	if (enable & MXC_INT_TE)
872 		val |= MX1_INTREG_TEEN;
873 	if (enable & MXC_INT_RR)
874 		val |= MX1_INTREG_RREN;
875 
876 	writel(val, spi_imx->base + MXC_CSPIINT);
877 }
878 
mx1_trigger(struct spi_imx_data * spi_imx)879 static void mx1_trigger(struct spi_imx_data *spi_imx)
880 {
881 	unsigned int reg;
882 
883 	reg = readl(spi_imx->base + MXC_CSPICTRL);
884 	reg |= MX1_CSPICTRL_XCH;
885 	writel(reg, spi_imx->base + MXC_CSPICTRL);
886 }
887 
mx1_prepare_message(struct spi_imx_data * spi_imx,struct spi_message * msg)888 static int mx1_prepare_message(struct spi_imx_data *spi_imx,
889 			       struct spi_message *msg)
890 {
891 	return 0;
892 }
893 
mx1_prepare_transfer(struct spi_imx_data * spi_imx,struct spi_device * spi)894 static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
895 				struct spi_device *spi)
896 {
897 	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
898 	unsigned int clk;
899 
900 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
901 		MX1_CSPICTRL_DR_SHIFT;
902 	spi_imx->spi_bus_clk = clk;
903 
904 	reg |= spi_imx->bits_per_word - 1;
905 
906 	if (spi->mode & SPI_CPHA)
907 		reg |= MX1_CSPICTRL_PHA;
908 	if (spi->mode & SPI_CPOL)
909 		reg |= MX1_CSPICTRL_POL;
910 
911 	writel(reg, spi_imx->base + MXC_CSPICTRL);
912 
913 	return 0;
914 }
915 
mx1_rx_available(struct spi_imx_data * spi_imx)916 static int mx1_rx_available(struct spi_imx_data *spi_imx)
917 {
918 	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
919 }
920 
mx1_reset(struct spi_imx_data * spi_imx)921 static void mx1_reset(struct spi_imx_data *spi_imx)
922 {
923 	writel(1, spi_imx->base + MXC_RESET);
924 }
925 
926 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
927 	.intctrl = mx1_intctrl,
928 	.prepare_message = mx1_prepare_message,
929 	.prepare_transfer = mx1_prepare_transfer,
930 	.trigger = mx1_trigger,
931 	.rx_available = mx1_rx_available,
932 	.reset = mx1_reset,
933 	.fifo_size = 8,
934 	.has_dmamode = false,
935 	.dynamic_burst = false,
936 	.has_slavemode = false,
937 	.devtype = IMX1_CSPI,
938 };
939 
940 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
941 	.intctrl = mx21_intctrl,
942 	.prepare_message = mx21_prepare_message,
943 	.prepare_transfer = mx21_prepare_transfer,
944 	.trigger = mx21_trigger,
945 	.rx_available = mx21_rx_available,
946 	.reset = mx21_reset,
947 	.fifo_size = 8,
948 	.has_dmamode = false,
949 	.dynamic_burst = false,
950 	.has_slavemode = false,
951 	.devtype = IMX21_CSPI,
952 };
953 
954 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
955 	/* i.mx27 cspi shares the functions with i.mx21 one */
956 	.intctrl = mx21_intctrl,
957 	.prepare_message = mx21_prepare_message,
958 	.prepare_transfer = mx21_prepare_transfer,
959 	.trigger = mx21_trigger,
960 	.rx_available = mx21_rx_available,
961 	.reset = mx21_reset,
962 	.fifo_size = 8,
963 	.has_dmamode = false,
964 	.dynamic_burst = false,
965 	.has_slavemode = false,
966 	.devtype = IMX27_CSPI,
967 };
968 
969 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
970 	.intctrl = mx31_intctrl,
971 	.prepare_message = mx31_prepare_message,
972 	.prepare_transfer = mx31_prepare_transfer,
973 	.trigger = mx31_trigger,
974 	.rx_available = mx31_rx_available,
975 	.reset = mx31_reset,
976 	.fifo_size = 8,
977 	.has_dmamode = false,
978 	.dynamic_burst = false,
979 	.has_slavemode = false,
980 	.devtype = IMX31_CSPI,
981 };
982 
983 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
984 	/* i.mx35 and later cspi shares the functions with i.mx31 one */
985 	.intctrl = mx31_intctrl,
986 	.prepare_message = mx31_prepare_message,
987 	.prepare_transfer = mx31_prepare_transfer,
988 	.trigger = mx31_trigger,
989 	.rx_available = mx31_rx_available,
990 	.reset = mx31_reset,
991 	.fifo_size = 8,
992 	.has_dmamode = true,
993 	.dynamic_burst = false,
994 	.has_slavemode = false,
995 	.devtype = IMX35_CSPI,
996 };
997 
998 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
999 	.intctrl = mx51_ecspi_intctrl,
1000 	.prepare_message = mx51_ecspi_prepare_message,
1001 	.prepare_transfer = mx51_ecspi_prepare_transfer,
1002 	.trigger = mx51_ecspi_trigger,
1003 	.rx_available = mx51_ecspi_rx_available,
1004 	.reset = mx51_ecspi_reset,
1005 	.setup_wml = mx51_setup_wml,
1006 	.disable_dma = mx51_disable_dma,
1007 	.fifo_size = 64,
1008 	.has_dmamode = true,
1009 	.dynamic_burst = true,
1010 	.has_slavemode = true,
1011 	.disable = mx51_ecspi_disable,
1012 	.devtype = IMX51_ECSPI,
1013 };
1014 
1015 static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
1016 	.intctrl = mx51_ecspi_intctrl,
1017 	.prepare_message = mx51_ecspi_prepare_message,
1018 	.prepare_transfer = mx51_ecspi_prepare_transfer,
1019 	.trigger = mx51_ecspi_trigger,
1020 	.rx_available = mx51_ecspi_rx_available,
1021 	.disable_dma = mx51_disable_dma,
1022 	.reset = mx51_ecspi_reset,
1023 	.fifo_size = 64,
1024 	.has_dmamode = true,
1025 	.has_slavemode = true,
1026 	.disable = mx51_ecspi_disable,
1027 	.devtype = IMX53_ECSPI,
1028 };
1029 
1030 static const struct platform_device_id spi_imx_devtype[] = {
1031 	{
1032 		.name = "imx1-cspi",
1033 		.driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
1034 	}, {
1035 		.name = "imx21-cspi",
1036 		.driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
1037 	}, {
1038 		.name = "imx27-cspi",
1039 		.driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
1040 	}, {
1041 		.name = "imx31-cspi",
1042 		.driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
1043 	}, {
1044 		.name = "imx35-cspi",
1045 		.driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
1046 	}, {
1047 		.name = "imx51-ecspi",
1048 		.driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
1049 	}, {
1050 		.name = "imx53-ecspi",
1051 		.driver_data = (kernel_ulong_t) &imx53_ecspi_devtype_data,
1052 	}, {
1053 		/* sentinel */
1054 	}
1055 };
1056 
1057 static const struct of_device_id spi_imx_dt_ids[] = {
1058 	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
1059 	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
1060 	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
1061 	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
1062 	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
1063 	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
1064 	{ .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
1065 	{ /* sentinel */ }
1066 };
1067 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
1068 
spi_imx_set_burst_len(struct spi_imx_data * spi_imx,int n_bits)1069 static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
1070 {
1071 	u32 ctrl;
1072 
1073 	ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
1074 	ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
1075 	ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
1076 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
1077 }
1078 
spi_imx_push(struct spi_imx_data * spi_imx)1079 static void spi_imx_push(struct spi_imx_data *spi_imx)
1080 {
1081 	unsigned int burst_len, fifo_words;
1082 
1083 	if (spi_imx->dynamic_burst)
1084 		fifo_words = 4;
1085 	else
1086 		fifo_words = spi_imx_bytes_per_word(spi_imx->bits_per_word);
1087 	/*
1088 	 * Reload the FIFO when the remaining bytes to be transferred in the
1089 	 * current burst is 0. This only applies when bits_per_word is a
1090 	 * multiple of 8.
1091 	 */
1092 	if (!spi_imx->remainder) {
1093 		if (spi_imx->dynamic_burst) {
1094 
1095 			/* We need to deal unaligned data first */
1096 			burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
1097 
1098 			if (!burst_len)
1099 				burst_len = MX51_ECSPI_CTRL_MAX_BURST;
1100 
1101 			spi_imx_set_burst_len(spi_imx, burst_len * 8);
1102 
1103 			spi_imx->remainder = burst_len;
1104 		} else {
1105 			spi_imx->remainder = fifo_words;
1106 		}
1107 	}
1108 
1109 	while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
1110 		if (!spi_imx->count)
1111 			break;
1112 		if (spi_imx->dynamic_burst &&
1113 		    spi_imx->txfifo >= DIV_ROUND_UP(spi_imx->remainder,
1114 						     fifo_words))
1115 			break;
1116 		spi_imx->tx(spi_imx);
1117 		spi_imx->txfifo++;
1118 	}
1119 
1120 	if (!spi_imx->slave_mode)
1121 		spi_imx->devtype_data->trigger(spi_imx);
1122 }
1123 
spi_imx_isr(int irq,void * dev_id)1124 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
1125 {
1126 	struct spi_imx_data *spi_imx = dev_id;
1127 
1128 	while (spi_imx->txfifo &&
1129 	       spi_imx->devtype_data->rx_available(spi_imx)) {
1130 		spi_imx->rx(spi_imx);
1131 		spi_imx->txfifo--;
1132 	}
1133 
1134 	if (spi_imx->count) {
1135 		spi_imx_push(spi_imx);
1136 		return IRQ_HANDLED;
1137 	}
1138 
1139 	if (spi_imx->txfifo) {
1140 		/* No data left to push, but still waiting for rx data,
1141 		 * enable receive data available interrupt.
1142 		 */
1143 		spi_imx->devtype_data->intctrl(
1144 				spi_imx, MXC_INT_RR);
1145 		return IRQ_HANDLED;
1146 	}
1147 
1148 	spi_imx->devtype_data->intctrl(spi_imx, 0);
1149 	complete(&spi_imx->xfer_done);
1150 
1151 	return IRQ_HANDLED;
1152 }
1153 
spi_imx_dma_configure(struct spi_master * master)1154 static int spi_imx_dma_configure(struct spi_master *master)
1155 {
1156 	int ret;
1157 	enum dma_slave_buswidth buswidth;
1158 	struct dma_slave_config rx = {}, tx = {};
1159 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1160 
1161 	switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
1162 	case 4:
1163 		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
1164 		break;
1165 	case 2:
1166 		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
1167 		break;
1168 	case 1:
1169 		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
1170 		break;
1171 	default:
1172 		return -EINVAL;
1173 	}
1174 
1175 	tx.direction = DMA_MEM_TO_DEV;
1176 	tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
1177 	tx.dst_addr_width = buswidth;
1178 	tx.dst_maxburst = spi_imx->wml;
1179 	ret = dmaengine_slave_config(master->dma_tx, &tx);
1180 	if (ret) {
1181 		dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
1182 		return ret;
1183 	}
1184 
1185 	rx.direction = DMA_DEV_TO_MEM;
1186 	rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
1187 	rx.src_addr_width = buswidth;
1188 	rx.src_maxburst = spi_imx->wml;
1189 	ret = dmaengine_slave_config(master->dma_rx, &rx);
1190 	if (ret) {
1191 		dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
1192 		return ret;
1193 	}
1194 
1195 	return 0;
1196 }
1197 
spi_imx_setupxfer(struct spi_device * spi,struct spi_transfer * t)1198 static int spi_imx_setupxfer(struct spi_device *spi,
1199 				 struct spi_transfer *t)
1200 {
1201 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1202 
1203 	if (!t)
1204 		return 0;
1205 
1206 	if (!t->speed_hz) {
1207 		if (!spi->max_speed_hz) {
1208 			dev_err(&spi->dev, "no speed_hz provided!\n");
1209 			return -EINVAL;
1210 		}
1211 		dev_dbg(&spi->dev, "using spi->max_speed_hz!\n");
1212 		spi_imx->spi_bus_clk = spi->max_speed_hz;
1213 	} else
1214 		spi_imx->spi_bus_clk = t->speed_hz;
1215 
1216 	spi_imx->bits_per_word = t->bits_per_word;
1217 
1218 	/*
1219 	 * Initialize the functions for transfer. To transfer non byte-aligned
1220 	 * words, we have to use multiple word-size bursts, we can't use
1221 	 * dynamic_burst in that case.
1222 	 */
1223 	if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode &&
1224 	    (spi_imx->bits_per_word == 8 ||
1225 	    spi_imx->bits_per_word == 16 ||
1226 	    spi_imx->bits_per_word == 32)) {
1227 
1228 		spi_imx->rx = spi_imx_buf_rx_swap;
1229 		spi_imx->tx = spi_imx_buf_tx_swap;
1230 		spi_imx->dynamic_burst = 1;
1231 
1232 	} else {
1233 		if (spi_imx->bits_per_word <= 8) {
1234 			spi_imx->rx = spi_imx_buf_rx_u8;
1235 			spi_imx->tx = spi_imx_buf_tx_u8;
1236 		} else if (spi_imx->bits_per_word <= 16) {
1237 			spi_imx->rx = spi_imx_buf_rx_u16;
1238 			spi_imx->tx = spi_imx_buf_tx_u16;
1239 		} else {
1240 			spi_imx->rx = spi_imx_buf_rx_u32;
1241 			spi_imx->tx = spi_imx_buf_tx_u32;
1242 		}
1243 		spi_imx->dynamic_burst = 0;
1244 	}
1245 
1246 	if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
1247 		spi_imx->usedma = true;
1248 	else
1249 		spi_imx->usedma = false;
1250 
1251 	if (is_imx53_ecspi(spi_imx) && spi_imx->slave_mode) {
1252 		spi_imx->rx = mx53_ecspi_rx_slave;
1253 		spi_imx->tx = mx53_ecspi_tx_slave;
1254 		spi_imx->slave_burst = t->len;
1255 	}
1256 
1257 	spi_imx->devtype_data->prepare_transfer(spi_imx, spi);
1258 
1259 	return 0;
1260 }
1261 
spi_imx_sdma_exit(struct spi_imx_data * spi_imx)1262 static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
1263 {
1264 	struct spi_master *master = spi_imx->bitbang.master;
1265 
1266 	if (master->dma_rx) {
1267 		dma_release_channel(master->dma_rx);
1268 		master->dma_rx = NULL;
1269 	}
1270 
1271 	if (master->dma_tx) {
1272 		dma_release_channel(master->dma_tx);
1273 		master->dma_tx = NULL;
1274 	}
1275 }
1276 
spi_imx_sdma_init(struct device * dev,struct spi_imx_data * spi_imx,struct spi_master * master)1277 static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
1278 			     struct spi_master *master)
1279 {
1280 	int ret;
1281 
1282 	/* use pio mode for i.mx6dl chip TKT238285 */
1283 	if (of_machine_is_compatible("fsl,imx6dl"))
1284 		return 0;
1285 
1286 	spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
1287 
1288 	/* Prepare for TX DMA: */
1289 	master->dma_tx = dma_request_chan(dev, "tx");
1290 	if (IS_ERR(master->dma_tx)) {
1291 		ret = PTR_ERR(master->dma_tx);
1292 		dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
1293 		master->dma_tx = NULL;
1294 		goto err;
1295 	}
1296 
1297 	/* Prepare for RX : */
1298 	master->dma_rx = dma_request_chan(dev, "rx");
1299 	if (IS_ERR(master->dma_rx)) {
1300 		ret = PTR_ERR(master->dma_rx);
1301 		dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
1302 		master->dma_rx = NULL;
1303 		goto err;
1304 	}
1305 
1306 	init_completion(&spi_imx->dma_rx_completion);
1307 	init_completion(&spi_imx->dma_tx_completion);
1308 	master->can_dma = spi_imx_can_dma;
1309 	master->max_dma_len = MAX_SDMA_BD_BYTES;
1310 	spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
1311 					 SPI_MASTER_MUST_TX;
1312 
1313 	return 0;
1314 err:
1315 	spi_imx_sdma_exit(spi_imx);
1316 	return ret;
1317 }
1318 
spi_imx_dma_rx_callback(void * cookie)1319 static void spi_imx_dma_rx_callback(void *cookie)
1320 {
1321 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1322 
1323 	complete(&spi_imx->dma_rx_completion);
1324 }
1325 
spi_imx_dma_tx_callback(void * cookie)1326 static void spi_imx_dma_tx_callback(void *cookie)
1327 {
1328 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1329 
1330 	complete(&spi_imx->dma_tx_completion);
1331 }
1332 
spi_imx_calculate_timeout(struct spi_imx_data * spi_imx,int size)1333 static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1334 {
1335 	unsigned long timeout = 0;
1336 
1337 	/* Time with actual data transfer and CS change delay related to HW */
1338 	timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1339 
1340 	/* Add extra second for scheduler related activities */
1341 	timeout += 1;
1342 
1343 	/* Double calculated timeout */
1344 	return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1345 }
1346 
spi_imx_dma_transfer(struct spi_imx_data * spi_imx,struct spi_transfer * transfer)1347 static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1348 				struct spi_transfer *transfer)
1349 {
1350 	struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1351 	unsigned long transfer_timeout;
1352 	unsigned long timeout;
1353 	struct spi_master *master = spi_imx->bitbang.master;
1354 	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1355 	struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
1356 	unsigned int bytes_per_word, i;
1357 	int ret;
1358 
1359 	/* Get the right burst length from the last sg to ensure no tail data */
1360 	bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
1361 	for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
1362 		if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
1363 			break;
1364 	}
1365 	/* Use 1 as wml in case no available burst length got */
1366 	if (i == 0)
1367 		i = 1;
1368 
1369 	spi_imx->wml =  i;
1370 
1371 	ret = spi_imx_dma_configure(master);
1372 	if (ret)
1373 		goto dma_failure_no_start;
1374 
1375 	if (!spi_imx->devtype_data->setup_wml) {
1376 		dev_err(spi_imx->dev, "No setup_wml()?\n");
1377 		ret = -EINVAL;
1378 		goto dma_failure_no_start;
1379 	}
1380 	spi_imx->devtype_data->setup_wml(spi_imx);
1381 
1382 	/*
1383 	 * The TX DMA setup starts the transfer, so make sure RX is configured
1384 	 * before TX.
1385 	 */
1386 	desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
1387 				rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1388 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1389 	if (!desc_rx) {
1390 		ret = -EINVAL;
1391 		goto dma_failure_no_start;
1392 	}
1393 
1394 	desc_rx->callback = spi_imx_dma_rx_callback;
1395 	desc_rx->callback_param = (void *)spi_imx;
1396 	dmaengine_submit(desc_rx);
1397 	reinit_completion(&spi_imx->dma_rx_completion);
1398 	dma_async_issue_pending(master->dma_rx);
1399 
1400 	desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
1401 				tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1402 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1403 	if (!desc_tx) {
1404 		dmaengine_terminate_all(master->dma_tx);
1405 		dmaengine_terminate_all(master->dma_rx);
1406 		return -EINVAL;
1407 	}
1408 
1409 	desc_tx->callback = spi_imx_dma_tx_callback;
1410 	desc_tx->callback_param = (void *)spi_imx;
1411 	dmaengine_submit(desc_tx);
1412 	reinit_completion(&spi_imx->dma_tx_completion);
1413 	dma_async_issue_pending(master->dma_tx);
1414 
1415 	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1416 
1417 	/* Wait SDMA to finish the data transfer.*/
1418 	timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1419 						transfer_timeout);
1420 	if (!timeout) {
1421 		dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1422 		dmaengine_terminate_all(master->dma_tx);
1423 		dmaengine_terminate_all(master->dma_rx);
1424 		return -ETIMEDOUT;
1425 	}
1426 
1427 	timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1428 					      transfer_timeout);
1429 	if (!timeout) {
1430 		dev_err(&master->dev, "I/O Error in DMA RX\n");
1431 		spi_imx->devtype_data->reset(spi_imx);
1432 		dmaengine_terminate_all(master->dma_rx);
1433 		return -ETIMEDOUT;
1434 	}
1435 
1436 	return transfer->len;
1437 /* fallback to pio */
1438 dma_failure_no_start:
1439 	transfer->error |= SPI_TRANS_FAIL_NO_START;
1440 	return ret;
1441 }
1442 
spi_imx_pio_transfer(struct spi_device * spi,struct spi_transfer * transfer)1443 static int spi_imx_pio_transfer(struct spi_device *spi,
1444 				struct spi_transfer *transfer)
1445 {
1446 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1447 	unsigned long transfer_timeout;
1448 	unsigned long timeout;
1449 
1450 	spi_imx->tx_buf = transfer->tx_buf;
1451 	spi_imx->rx_buf = transfer->rx_buf;
1452 	spi_imx->count = transfer->len;
1453 	spi_imx->txfifo = 0;
1454 	spi_imx->remainder = 0;
1455 
1456 	reinit_completion(&spi_imx->xfer_done);
1457 
1458 	spi_imx_push(spi_imx);
1459 
1460 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1461 
1462 	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1463 
1464 	timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
1465 					      transfer_timeout);
1466 	if (!timeout) {
1467 		dev_err(&spi->dev, "I/O Error in PIO\n");
1468 		spi_imx->devtype_data->reset(spi_imx);
1469 		return -ETIMEDOUT;
1470 	}
1471 
1472 	return transfer->len;
1473 }
1474 
spi_imx_pio_transfer_slave(struct spi_device * spi,struct spi_transfer * transfer)1475 static int spi_imx_pio_transfer_slave(struct spi_device *spi,
1476 				      struct spi_transfer *transfer)
1477 {
1478 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1479 	int ret = transfer->len;
1480 
1481 	if (is_imx53_ecspi(spi_imx) &&
1482 	    transfer->len > MX53_MAX_TRANSFER_BYTES) {
1483 		dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
1484 			MX53_MAX_TRANSFER_BYTES);
1485 		return -EMSGSIZE;
1486 	}
1487 
1488 	spi_imx->tx_buf = transfer->tx_buf;
1489 	spi_imx->rx_buf = transfer->rx_buf;
1490 	spi_imx->count = transfer->len;
1491 	spi_imx->txfifo = 0;
1492 	spi_imx->remainder = 0;
1493 
1494 	reinit_completion(&spi_imx->xfer_done);
1495 	spi_imx->slave_aborted = false;
1496 
1497 	spi_imx_push(spi_imx);
1498 
1499 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
1500 
1501 	if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
1502 	    spi_imx->slave_aborted) {
1503 		dev_dbg(&spi->dev, "interrupted\n");
1504 		ret = -EINTR;
1505 	}
1506 
1507 	/* ecspi has a HW issue when works in Slave mode,
1508 	 * after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
1509 	 * ECSPI_TXDATA keeps shift out the last word data,
1510 	 * so we have to disable ECSPI when in slave mode after the
1511 	 * transfer completes
1512 	 */
1513 	if (spi_imx->devtype_data->disable)
1514 		spi_imx->devtype_data->disable(spi_imx);
1515 
1516 	return ret;
1517 }
1518 
spi_imx_transfer(struct spi_device * spi,struct spi_transfer * transfer)1519 static int spi_imx_transfer(struct spi_device *spi,
1520 				struct spi_transfer *transfer)
1521 {
1522 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1523 
1524 	transfer->effective_speed_hz = spi_imx->spi_bus_clk;
1525 
1526 	/* flush rxfifo before transfer */
1527 	while (spi_imx->devtype_data->rx_available(spi_imx))
1528 		readl(spi_imx->base + MXC_CSPIRXDATA);
1529 
1530 	if (spi_imx->slave_mode)
1531 		return spi_imx_pio_transfer_slave(spi, transfer);
1532 
1533 	if (spi_imx->usedma)
1534 		return spi_imx_dma_transfer(spi_imx, transfer);
1535 
1536 	return spi_imx_pio_transfer(spi, transfer);
1537 }
1538 
spi_imx_setup(struct spi_device * spi)1539 static int spi_imx_setup(struct spi_device *spi)
1540 {
1541 	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1542 		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1543 
1544 	return 0;
1545 }
1546 
spi_imx_cleanup(struct spi_device * spi)1547 static void spi_imx_cleanup(struct spi_device *spi)
1548 {
1549 }
1550 
1551 static int
spi_imx_prepare_message(struct spi_master * master,struct spi_message * msg)1552 spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1553 {
1554 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1555 	int ret;
1556 
1557 	ret = pm_runtime_get_sync(spi_imx->dev);
1558 	if (ret < 0) {
1559 		pm_runtime_put_noidle(spi_imx->dev);
1560 		dev_err(spi_imx->dev, "failed to enable clock\n");
1561 		return ret;
1562 	}
1563 
1564 	ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
1565 	if (ret) {
1566 		pm_runtime_mark_last_busy(spi_imx->dev);
1567 		pm_runtime_put_autosuspend(spi_imx->dev);
1568 	}
1569 
1570 	return ret;
1571 }
1572 
1573 static int
spi_imx_unprepare_message(struct spi_master * master,struct spi_message * msg)1574 spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1575 {
1576 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1577 
1578 	pm_runtime_mark_last_busy(spi_imx->dev);
1579 	pm_runtime_put_autosuspend(spi_imx->dev);
1580 	return 0;
1581 }
1582 
spi_imx_slave_abort(struct spi_master * master)1583 static int spi_imx_slave_abort(struct spi_master *master)
1584 {
1585 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1586 
1587 	spi_imx->slave_aborted = true;
1588 	complete(&spi_imx->xfer_done);
1589 
1590 	return 0;
1591 }
1592 
spi_imx_probe(struct platform_device * pdev)1593 static int spi_imx_probe(struct platform_device *pdev)
1594 {
1595 	struct device_node *np = pdev->dev.of_node;
1596 	const struct of_device_id *of_id =
1597 			of_match_device(spi_imx_dt_ids, &pdev->dev);
1598 	struct spi_master *master;
1599 	struct spi_imx_data *spi_imx;
1600 	struct resource *res;
1601 	int ret, irq, spi_drctl;
1602 	const struct spi_imx_devtype_data *devtype_data = of_id ? of_id->data :
1603 		(struct spi_imx_devtype_data *)pdev->id_entry->driver_data;
1604 	bool slave_mode;
1605 	u32 val;
1606 
1607 	slave_mode = devtype_data->has_slavemode &&
1608 			of_property_read_bool(np, "spi-slave");
1609 	if (slave_mode)
1610 		master = spi_alloc_slave(&pdev->dev,
1611 					 sizeof(struct spi_imx_data));
1612 	else
1613 		master = spi_alloc_master(&pdev->dev,
1614 					  sizeof(struct spi_imx_data));
1615 	if (!master)
1616 		return -ENOMEM;
1617 
1618 	ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
1619 	if ((ret < 0) || (spi_drctl >= 0x3)) {
1620 		/* '11' is reserved */
1621 		spi_drctl = 0;
1622 	}
1623 
1624 	platform_set_drvdata(pdev, master);
1625 
1626 	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1627 	master->bus_num = np ? -1 : pdev->id;
1628 	master->use_gpio_descriptors = true;
1629 
1630 	spi_imx = spi_master_get_devdata(master);
1631 	spi_imx->bitbang.master = master;
1632 	spi_imx->dev = &pdev->dev;
1633 	spi_imx->slave_mode = slave_mode;
1634 
1635 	spi_imx->devtype_data = devtype_data;
1636 
1637 	/*
1638 	 * Get number of chip selects from device properties. This can be
1639 	 * coming from device tree or boardfiles, if it is not defined,
1640 	 * a default value of 3 chip selects will be used, as all the legacy
1641 	 * board files have <= 3 chip selects.
1642 	 */
1643 	if (!device_property_read_u32(&pdev->dev, "num-cs", &val))
1644 		master->num_chipselect = val;
1645 	else
1646 		master->num_chipselect = 3;
1647 
1648 	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1649 	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1650 	spi_imx->bitbang.master->setup = spi_imx_setup;
1651 	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1652 	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1653 	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1654 	spi_imx->bitbang.master->slave_abort = spi_imx_slave_abort;
1655 	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
1656 					     | SPI_NO_CS;
1657 	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
1658 	    is_imx53_ecspi(spi_imx))
1659 		spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY;
1660 
1661 	spi_imx->spi_drctl = spi_drctl;
1662 
1663 	init_completion(&spi_imx->xfer_done);
1664 
1665 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1666 	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1667 	if (IS_ERR(spi_imx->base)) {
1668 		ret = PTR_ERR(spi_imx->base);
1669 		goto out_master_put;
1670 	}
1671 	spi_imx->base_phys = res->start;
1672 
1673 	irq = platform_get_irq(pdev, 0);
1674 	if (irq < 0) {
1675 		ret = irq;
1676 		goto out_master_put;
1677 	}
1678 
1679 	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1680 			       dev_name(&pdev->dev), spi_imx);
1681 	if (ret) {
1682 		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1683 		goto out_master_put;
1684 	}
1685 
1686 	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1687 	if (IS_ERR(spi_imx->clk_ipg)) {
1688 		ret = PTR_ERR(spi_imx->clk_ipg);
1689 		goto out_master_put;
1690 	}
1691 
1692 	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1693 	if (IS_ERR(spi_imx->clk_per)) {
1694 		ret = PTR_ERR(spi_imx->clk_per);
1695 		goto out_master_put;
1696 	}
1697 
1698 	ret = clk_prepare_enable(spi_imx->clk_per);
1699 	if (ret)
1700 		goto out_master_put;
1701 
1702 	ret = clk_prepare_enable(spi_imx->clk_ipg);
1703 	if (ret)
1704 		goto out_put_per;
1705 
1706 	pm_runtime_set_autosuspend_delay(spi_imx->dev, MXC_RPM_TIMEOUT);
1707 	pm_runtime_use_autosuspend(spi_imx->dev);
1708 	pm_runtime_get_noresume(spi_imx->dev);
1709 	pm_runtime_set_active(spi_imx->dev);
1710 	pm_runtime_enable(spi_imx->dev);
1711 
1712 	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1713 	/*
1714 	 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1715 	 * if validated on other chips.
1716 	 */
1717 	if (spi_imx->devtype_data->has_dmamode) {
1718 		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
1719 		if (ret == -EPROBE_DEFER)
1720 			goto out_runtime_pm_put;
1721 
1722 		if (ret < 0)
1723 			dev_dbg(&pdev->dev, "dma setup error %d, use pio\n",
1724 				ret);
1725 	}
1726 
1727 	spi_imx->devtype_data->reset(spi_imx);
1728 
1729 	spi_imx->devtype_data->intctrl(spi_imx, 0);
1730 
1731 	master->dev.of_node = pdev->dev.of_node;
1732 	ret = spi_bitbang_start(&spi_imx->bitbang);
1733 	if (ret) {
1734 		dev_err_probe(&pdev->dev, ret, "bitbang start failed\n");
1735 		goto out_bitbang_start;
1736 	}
1737 
1738 	pm_runtime_mark_last_busy(spi_imx->dev);
1739 	pm_runtime_put_autosuspend(spi_imx->dev);
1740 
1741 	return ret;
1742 
1743 out_bitbang_start:
1744 	if (spi_imx->devtype_data->has_dmamode)
1745 		spi_imx_sdma_exit(spi_imx);
1746 out_runtime_pm_put:
1747 	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1748 	pm_runtime_set_suspended(&pdev->dev);
1749 	pm_runtime_disable(spi_imx->dev);
1750 
1751 	clk_disable_unprepare(spi_imx->clk_ipg);
1752 out_put_per:
1753 	clk_disable_unprepare(spi_imx->clk_per);
1754 out_master_put:
1755 	spi_master_put(master);
1756 
1757 	return ret;
1758 }
1759 
spi_imx_remove(struct platform_device * pdev)1760 static int spi_imx_remove(struct platform_device *pdev)
1761 {
1762 	struct spi_master *master = platform_get_drvdata(pdev);
1763 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1764 	int ret;
1765 
1766 	spi_bitbang_stop(&spi_imx->bitbang);
1767 
1768 	ret = pm_runtime_get_sync(spi_imx->dev);
1769 	if (ret < 0) {
1770 		pm_runtime_put_noidle(spi_imx->dev);
1771 		dev_err(spi_imx->dev, "failed to enable clock\n");
1772 		return ret;
1773 	}
1774 
1775 	writel(0, spi_imx->base + MXC_CSPICTRL);
1776 
1777 	pm_runtime_dont_use_autosuspend(spi_imx->dev);
1778 	pm_runtime_put_sync(spi_imx->dev);
1779 	pm_runtime_disable(spi_imx->dev);
1780 
1781 	spi_imx_sdma_exit(spi_imx);
1782 	spi_master_put(master);
1783 
1784 	return 0;
1785 }
1786 
spi_imx_runtime_resume(struct device * dev)1787 static int __maybe_unused spi_imx_runtime_resume(struct device *dev)
1788 {
1789 	struct spi_master *master = dev_get_drvdata(dev);
1790 	struct spi_imx_data *spi_imx;
1791 	int ret;
1792 
1793 	spi_imx = spi_master_get_devdata(master);
1794 
1795 	ret = clk_prepare_enable(spi_imx->clk_per);
1796 	if (ret)
1797 		return ret;
1798 
1799 	ret = clk_prepare_enable(spi_imx->clk_ipg);
1800 	if (ret) {
1801 		clk_disable_unprepare(spi_imx->clk_per);
1802 		return ret;
1803 	}
1804 
1805 	return 0;
1806 }
1807 
spi_imx_runtime_suspend(struct device * dev)1808 static int __maybe_unused spi_imx_runtime_suspend(struct device *dev)
1809 {
1810 	struct spi_master *master = dev_get_drvdata(dev);
1811 	struct spi_imx_data *spi_imx;
1812 
1813 	spi_imx = spi_master_get_devdata(master);
1814 
1815 	clk_disable_unprepare(spi_imx->clk_per);
1816 	clk_disable_unprepare(spi_imx->clk_ipg);
1817 
1818 	return 0;
1819 }
1820 
spi_imx_suspend(struct device * dev)1821 static int __maybe_unused spi_imx_suspend(struct device *dev)
1822 {
1823 	pinctrl_pm_select_sleep_state(dev);
1824 	return 0;
1825 }
1826 
spi_imx_resume(struct device * dev)1827 static int __maybe_unused spi_imx_resume(struct device *dev)
1828 {
1829 	pinctrl_pm_select_default_state(dev);
1830 	return 0;
1831 }
1832 
1833 static const struct dev_pm_ops imx_spi_pm = {
1834 	SET_RUNTIME_PM_OPS(spi_imx_runtime_suspend,
1835 				spi_imx_runtime_resume, NULL)
1836 	SET_SYSTEM_SLEEP_PM_OPS(spi_imx_suspend, spi_imx_resume)
1837 };
1838 
1839 static struct platform_driver spi_imx_driver = {
1840 	.driver = {
1841 		   .name = DRIVER_NAME,
1842 		   .of_match_table = spi_imx_dt_ids,
1843 		   .pm = &imx_spi_pm,
1844 	},
1845 	.id_table = spi_imx_devtype,
1846 	.probe = spi_imx_probe,
1847 	.remove = spi_imx_remove,
1848 };
1849 module_platform_driver(spi_imx_driver);
1850 
1851 MODULE_DESCRIPTION("SPI Controller driver");
1852 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1853 MODULE_LICENSE("GPL");
1854 MODULE_ALIAS("platform:" DRIVER_NAME);
1855