xref: /openbmc/linux/drivers/spi/spi-imx.c (revision 79f08d9e)
1 /*
2  * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
3  * Copyright (C) 2008 Juergen Beisert
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License
7  * as published by the Free Software Foundation; either version 2
8  * of the License, or (at your option) any later version.
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the
16  * Free Software Foundation
17  * 51 Franklin Street, Fifth Floor
18  * Boston, MA  02110-1301, USA.
19  */
20 
21 #include <linux/clk.h>
22 #include <linux/completion.h>
23 #include <linux/delay.h>
24 #include <linux/err.h>
25 #include <linux/gpio.h>
26 #include <linux/init.h>
27 #include <linux/interrupt.h>
28 #include <linux/io.h>
29 #include <linux/irq.h>
30 #include <linux/kernel.h>
31 #include <linux/module.h>
32 #include <linux/platform_device.h>
33 #include <linux/slab.h>
34 #include <linux/spi/spi.h>
35 #include <linux/spi/spi_bitbang.h>
36 #include <linux/types.h>
37 #include <linux/of.h>
38 #include <linux/of_device.h>
39 #include <linux/of_gpio.h>
40 
41 #include <linux/platform_data/spi-imx.h>
42 
43 #define DRIVER_NAME "spi_imx"
44 
45 #define MXC_CSPIRXDATA		0x00
46 #define MXC_CSPITXDATA		0x04
47 #define MXC_CSPICTRL		0x08
48 #define MXC_CSPIINT		0x0c
49 #define MXC_RESET		0x1c
50 
51 /* generic defines to abstract from the different register layouts */
52 #define MXC_INT_RR	(1 << 0) /* Receive data ready interrupt */
53 #define MXC_INT_TE	(1 << 1) /* Transmit FIFO empty interrupt */
54 
55 struct spi_imx_config {
56 	unsigned int speed_hz;
57 	unsigned int bpw;
58 	unsigned int mode;
59 	u8 cs;
60 };
61 
62 enum spi_imx_devtype {
63 	IMX1_CSPI,
64 	IMX21_CSPI,
65 	IMX27_CSPI,
66 	IMX31_CSPI,
67 	IMX35_CSPI,	/* CSPI on all i.mx except above */
68 	IMX51_ECSPI,	/* ECSPI on i.mx51 and later */
69 };
70 
71 struct spi_imx_data;
72 
73 struct spi_imx_devtype_data {
74 	void (*intctrl)(struct spi_imx_data *, int);
75 	int (*config)(struct spi_imx_data *, struct spi_imx_config *);
76 	void (*trigger)(struct spi_imx_data *);
77 	int (*rx_available)(struct spi_imx_data *);
78 	void (*reset)(struct spi_imx_data *);
79 	enum spi_imx_devtype devtype;
80 };
81 
82 struct spi_imx_data {
83 	struct spi_bitbang bitbang;
84 
85 	struct completion xfer_done;
86 	void __iomem *base;
87 	int irq;
88 	struct clk *clk_per;
89 	struct clk *clk_ipg;
90 	unsigned long spi_clk;
91 
92 	unsigned int count;
93 	void (*tx)(struct spi_imx_data *);
94 	void (*rx)(struct spi_imx_data *);
95 	void *rx_buf;
96 	const void *tx_buf;
97 	unsigned int txfifo; /* number of words pushed in tx FIFO */
98 
99 	const struct spi_imx_devtype_data *devtype_data;
100 	int chipselect[0];
101 };
102 
103 static inline int is_imx27_cspi(struct spi_imx_data *d)
104 {
105 	return d->devtype_data->devtype == IMX27_CSPI;
106 }
107 
108 static inline int is_imx35_cspi(struct spi_imx_data *d)
109 {
110 	return d->devtype_data->devtype == IMX35_CSPI;
111 }
112 
113 static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d)
114 {
115 	return (d->devtype_data->devtype == IMX51_ECSPI) ? 64 : 8;
116 }
117 
118 #define MXC_SPI_BUF_RX(type)						\
119 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
120 {									\
121 	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
122 									\
123 	if (spi_imx->rx_buf) {						\
124 		*(type *)spi_imx->rx_buf = val;				\
125 		spi_imx->rx_buf += sizeof(type);			\
126 	}								\
127 }
128 
129 #define MXC_SPI_BUF_TX(type)						\
130 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
131 {									\
132 	type val = 0;							\
133 									\
134 	if (spi_imx->tx_buf) {						\
135 		val = *(type *)spi_imx->tx_buf;				\
136 		spi_imx->tx_buf += sizeof(type);			\
137 	}								\
138 									\
139 	spi_imx->count -= sizeof(type);					\
140 									\
141 	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
142 }
143 
144 MXC_SPI_BUF_RX(u8)
145 MXC_SPI_BUF_TX(u8)
146 MXC_SPI_BUF_RX(u16)
147 MXC_SPI_BUF_TX(u16)
148 MXC_SPI_BUF_RX(u32)
149 MXC_SPI_BUF_TX(u32)
150 
151 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
152  * (which is currently not the case in this driver)
153  */
154 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
155 	256, 384, 512, 768, 1024};
156 
157 /* MX21, MX27 */
158 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
159 		unsigned int fspi, unsigned int max)
160 {
161 	int i;
162 
163 	for (i = 2; i < max; i++)
164 		if (fspi * mxc_clkdivs[i] >= fin)
165 			return i;
166 
167 	return max;
168 }
169 
170 /* MX1, MX31, MX35, MX51 CSPI */
171 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
172 		unsigned int fspi)
173 {
174 	int i, div = 4;
175 
176 	for (i = 0; i < 7; i++) {
177 		if (fspi * div >= fin)
178 			return i;
179 		div <<= 1;
180 	}
181 
182 	return 7;
183 }
184 
185 #define MX51_ECSPI_CTRL		0x08
186 #define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
187 #define MX51_ECSPI_CTRL_XCH		(1 <<  2)
188 #define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
189 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
190 #define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
191 #define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
192 #define MX51_ECSPI_CTRL_BL_OFFSET	20
193 
194 #define MX51_ECSPI_CONFIG	0x0c
195 #define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
196 #define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
197 #define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
198 #define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
199 #define MX51_ECSPI_CONFIG_SCLKCTL(cs)	(1 << ((cs) + 20))
200 
201 #define MX51_ECSPI_INT		0x10
202 #define MX51_ECSPI_INT_TEEN		(1 <<  0)
203 #define MX51_ECSPI_INT_RREN		(1 <<  3)
204 
205 #define MX51_ECSPI_STAT		0x18
206 #define MX51_ECSPI_STAT_RR		(1 <<  3)
207 
208 /* MX51 eCSPI */
209 static unsigned int mx51_ecspi_clkdiv(unsigned int fin, unsigned int fspi)
210 {
211 	/*
212 	 * there are two 4-bit dividers, the pre-divider divides by
213 	 * $pre, the post-divider by 2^$post
214 	 */
215 	unsigned int pre, post;
216 
217 	if (unlikely(fspi > fin))
218 		return 0;
219 
220 	post = fls(fin) - fls(fspi);
221 	if (fin > fspi << post)
222 		post++;
223 
224 	/* now we have: (fin <= fspi << post) with post being minimal */
225 
226 	post = max(4U, post) - 4;
227 	if (unlikely(post > 0xf)) {
228 		pr_err("%s: cannot set clock freq: %u (base freq: %u)\n",
229 				__func__, fspi, fin);
230 		return 0xff;
231 	}
232 
233 	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
234 
235 	pr_debug("%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
236 			__func__, fin, fspi, post, pre);
237 	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
238 		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
239 }
240 
241 static void __maybe_unused mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
242 {
243 	unsigned val = 0;
244 
245 	if (enable & MXC_INT_TE)
246 		val |= MX51_ECSPI_INT_TEEN;
247 
248 	if (enable & MXC_INT_RR)
249 		val |= MX51_ECSPI_INT_RREN;
250 
251 	writel(val, spi_imx->base + MX51_ECSPI_INT);
252 }
253 
254 static void __maybe_unused mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
255 {
256 	u32 reg;
257 
258 	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
259 	reg |= MX51_ECSPI_CTRL_XCH;
260 	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
261 }
262 
263 static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx,
264 		struct spi_imx_config *config)
265 {
266 	u32 ctrl = MX51_ECSPI_CTRL_ENABLE, cfg = 0;
267 
268 	/*
269 	 * The hardware seems to have a race condition when changing modes. The
270 	 * current assumption is that the selection of the channel arrives
271 	 * earlier in the hardware than the mode bits when they are written at
272 	 * the same time.
273 	 * So set master mode for all channels as we do not support slave mode.
274 	 */
275 	ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
276 
277 	/* set clock speed */
278 	ctrl |= mx51_ecspi_clkdiv(spi_imx->spi_clk, config->speed_hz);
279 
280 	/* set chip select to use */
281 	ctrl |= MX51_ECSPI_CTRL_CS(config->cs);
282 
283 	ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET;
284 
285 	cfg |= MX51_ECSPI_CONFIG_SBBCTRL(config->cs);
286 
287 	if (config->mode & SPI_CPHA)
288 		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(config->cs);
289 
290 	if (config->mode & SPI_CPOL) {
291 		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(config->cs);
292 		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(config->cs);
293 	}
294 	if (config->mode & SPI_CS_HIGH)
295 		cfg |= MX51_ECSPI_CONFIG_SSBPOL(config->cs);
296 
297 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
298 	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
299 
300 	return 0;
301 }
302 
303 static int __maybe_unused mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
304 {
305 	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
306 }
307 
308 static void __maybe_unused mx51_ecspi_reset(struct spi_imx_data *spi_imx)
309 {
310 	/* drain receive buffer */
311 	while (mx51_ecspi_rx_available(spi_imx))
312 		readl(spi_imx->base + MXC_CSPIRXDATA);
313 }
314 
315 #define MX31_INTREG_TEEN	(1 << 0)
316 #define MX31_INTREG_RREN	(1 << 3)
317 
318 #define MX31_CSPICTRL_ENABLE	(1 << 0)
319 #define MX31_CSPICTRL_MASTER	(1 << 1)
320 #define MX31_CSPICTRL_XCH	(1 << 2)
321 #define MX31_CSPICTRL_POL	(1 << 4)
322 #define MX31_CSPICTRL_PHA	(1 << 5)
323 #define MX31_CSPICTRL_SSCTL	(1 << 6)
324 #define MX31_CSPICTRL_SSPOL	(1 << 7)
325 #define MX31_CSPICTRL_BC_SHIFT	8
326 #define MX35_CSPICTRL_BL_SHIFT	20
327 #define MX31_CSPICTRL_CS_SHIFT	24
328 #define MX35_CSPICTRL_CS_SHIFT	12
329 #define MX31_CSPICTRL_DR_SHIFT	16
330 
331 #define MX31_CSPISTATUS		0x14
332 #define MX31_STATUS_RR		(1 << 3)
333 
334 /* These functions also work for the i.MX35, but be aware that
335  * the i.MX35 has a slightly different register layout for bits
336  * we do not use here.
337  */
338 static void __maybe_unused mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
339 {
340 	unsigned int val = 0;
341 
342 	if (enable & MXC_INT_TE)
343 		val |= MX31_INTREG_TEEN;
344 	if (enable & MXC_INT_RR)
345 		val |= MX31_INTREG_RREN;
346 
347 	writel(val, spi_imx->base + MXC_CSPIINT);
348 }
349 
350 static void __maybe_unused mx31_trigger(struct spi_imx_data *spi_imx)
351 {
352 	unsigned int reg;
353 
354 	reg = readl(spi_imx->base + MXC_CSPICTRL);
355 	reg |= MX31_CSPICTRL_XCH;
356 	writel(reg, spi_imx->base + MXC_CSPICTRL);
357 }
358 
359 static int __maybe_unused mx31_config(struct spi_imx_data *spi_imx,
360 		struct spi_imx_config *config)
361 {
362 	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
363 	int cs = spi_imx->chipselect[config->cs];
364 
365 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
366 		MX31_CSPICTRL_DR_SHIFT;
367 
368 	if (is_imx35_cspi(spi_imx)) {
369 		reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT;
370 		reg |= MX31_CSPICTRL_SSCTL;
371 	} else {
372 		reg |= (config->bpw - 1) << MX31_CSPICTRL_BC_SHIFT;
373 	}
374 
375 	if (config->mode & SPI_CPHA)
376 		reg |= MX31_CSPICTRL_PHA;
377 	if (config->mode & SPI_CPOL)
378 		reg |= MX31_CSPICTRL_POL;
379 	if (config->mode & SPI_CS_HIGH)
380 		reg |= MX31_CSPICTRL_SSPOL;
381 	if (cs < 0)
382 		reg |= (cs + 32) <<
383 			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
384 						  MX31_CSPICTRL_CS_SHIFT);
385 
386 	writel(reg, spi_imx->base + MXC_CSPICTRL);
387 
388 	return 0;
389 }
390 
391 static int __maybe_unused mx31_rx_available(struct spi_imx_data *spi_imx)
392 {
393 	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
394 }
395 
396 static void __maybe_unused mx31_reset(struct spi_imx_data *spi_imx)
397 {
398 	/* drain receive buffer */
399 	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
400 		readl(spi_imx->base + MXC_CSPIRXDATA);
401 }
402 
403 #define MX21_INTREG_RR		(1 << 4)
404 #define MX21_INTREG_TEEN	(1 << 9)
405 #define MX21_INTREG_RREN	(1 << 13)
406 
407 #define MX21_CSPICTRL_POL	(1 << 5)
408 #define MX21_CSPICTRL_PHA	(1 << 6)
409 #define MX21_CSPICTRL_SSPOL	(1 << 8)
410 #define MX21_CSPICTRL_XCH	(1 << 9)
411 #define MX21_CSPICTRL_ENABLE	(1 << 10)
412 #define MX21_CSPICTRL_MASTER	(1 << 11)
413 #define MX21_CSPICTRL_DR_SHIFT	14
414 #define MX21_CSPICTRL_CS_SHIFT	19
415 
416 static void __maybe_unused mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
417 {
418 	unsigned int val = 0;
419 
420 	if (enable & MXC_INT_TE)
421 		val |= MX21_INTREG_TEEN;
422 	if (enable & MXC_INT_RR)
423 		val |= MX21_INTREG_RREN;
424 
425 	writel(val, spi_imx->base + MXC_CSPIINT);
426 }
427 
428 static void __maybe_unused mx21_trigger(struct spi_imx_data *spi_imx)
429 {
430 	unsigned int reg;
431 
432 	reg = readl(spi_imx->base + MXC_CSPICTRL);
433 	reg |= MX21_CSPICTRL_XCH;
434 	writel(reg, spi_imx->base + MXC_CSPICTRL);
435 }
436 
437 static int __maybe_unused mx21_config(struct spi_imx_data *spi_imx,
438 		struct spi_imx_config *config)
439 {
440 	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
441 	int cs = spi_imx->chipselect[config->cs];
442 	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
443 
444 	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max) <<
445 		MX21_CSPICTRL_DR_SHIFT;
446 	reg |= config->bpw - 1;
447 
448 	if (config->mode & SPI_CPHA)
449 		reg |= MX21_CSPICTRL_PHA;
450 	if (config->mode & SPI_CPOL)
451 		reg |= MX21_CSPICTRL_POL;
452 	if (config->mode & SPI_CS_HIGH)
453 		reg |= MX21_CSPICTRL_SSPOL;
454 	if (cs < 0)
455 		reg |= (cs + 32) << MX21_CSPICTRL_CS_SHIFT;
456 
457 	writel(reg, spi_imx->base + MXC_CSPICTRL);
458 
459 	return 0;
460 }
461 
462 static int __maybe_unused mx21_rx_available(struct spi_imx_data *spi_imx)
463 {
464 	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
465 }
466 
467 static void __maybe_unused mx21_reset(struct spi_imx_data *spi_imx)
468 {
469 	writel(1, spi_imx->base + MXC_RESET);
470 }
471 
472 #define MX1_INTREG_RR		(1 << 3)
473 #define MX1_INTREG_TEEN		(1 << 8)
474 #define MX1_INTREG_RREN		(1 << 11)
475 
476 #define MX1_CSPICTRL_POL	(1 << 4)
477 #define MX1_CSPICTRL_PHA	(1 << 5)
478 #define MX1_CSPICTRL_XCH	(1 << 8)
479 #define MX1_CSPICTRL_ENABLE	(1 << 9)
480 #define MX1_CSPICTRL_MASTER	(1 << 10)
481 #define MX1_CSPICTRL_DR_SHIFT	13
482 
483 static void __maybe_unused mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
484 {
485 	unsigned int val = 0;
486 
487 	if (enable & MXC_INT_TE)
488 		val |= MX1_INTREG_TEEN;
489 	if (enable & MXC_INT_RR)
490 		val |= MX1_INTREG_RREN;
491 
492 	writel(val, spi_imx->base + MXC_CSPIINT);
493 }
494 
495 static void __maybe_unused mx1_trigger(struct spi_imx_data *spi_imx)
496 {
497 	unsigned int reg;
498 
499 	reg = readl(spi_imx->base + MXC_CSPICTRL);
500 	reg |= MX1_CSPICTRL_XCH;
501 	writel(reg, spi_imx->base + MXC_CSPICTRL);
502 }
503 
504 static int __maybe_unused mx1_config(struct spi_imx_data *spi_imx,
505 		struct spi_imx_config *config)
506 {
507 	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
508 
509 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
510 		MX1_CSPICTRL_DR_SHIFT;
511 	reg |= config->bpw - 1;
512 
513 	if (config->mode & SPI_CPHA)
514 		reg |= MX1_CSPICTRL_PHA;
515 	if (config->mode & SPI_CPOL)
516 		reg |= MX1_CSPICTRL_POL;
517 
518 	writel(reg, spi_imx->base + MXC_CSPICTRL);
519 
520 	return 0;
521 }
522 
523 static int __maybe_unused mx1_rx_available(struct spi_imx_data *spi_imx)
524 {
525 	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
526 }
527 
528 static void __maybe_unused mx1_reset(struct spi_imx_data *spi_imx)
529 {
530 	writel(1, spi_imx->base + MXC_RESET);
531 }
532 
533 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
534 	.intctrl = mx1_intctrl,
535 	.config = mx1_config,
536 	.trigger = mx1_trigger,
537 	.rx_available = mx1_rx_available,
538 	.reset = mx1_reset,
539 	.devtype = IMX1_CSPI,
540 };
541 
542 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
543 	.intctrl = mx21_intctrl,
544 	.config = mx21_config,
545 	.trigger = mx21_trigger,
546 	.rx_available = mx21_rx_available,
547 	.reset = mx21_reset,
548 	.devtype = IMX21_CSPI,
549 };
550 
551 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
552 	/* i.mx27 cspi shares the functions with i.mx21 one */
553 	.intctrl = mx21_intctrl,
554 	.config = mx21_config,
555 	.trigger = mx21_trigger,
556 	.rx_available = mx21_rx_available,
557 	.reset = mx21_reset,
558 	.devtype = IMX27_CSPI,
559 };
560 
561 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
562 	.intctrl = mx31_intctrl,
563 	.config = mx31_config,
564 	.trigger = mx31_trigger,
565 	.rx_available = mx31_rx_available,
566 	.reset = mx31_reset,
567 	.devtype = IMX31_CSPI,
568 };
569 
570 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
571 	/* i.mx35 and later cspi shares the functions with i.mx31 one */
572 	.intctrl = mx31_intctrl,
573 	.config = mx31_config,
574 	.trigger = mx31_trigger,
575 	.rx_available = mx31_rx_available,
576 	.reset = mx31_reset,
577 	.devtype = IMX35_CSPI,
578 };
579 
580 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
581 	.intctrl = mx51_ecspi_intctrl,
582 	.config = mx51_ecspi_config,
583 	.trigger = mx51_ecspi_trigger,
584 	.rx_available = mx51_ecspi_rx_available,
585 	.reset = mx51_ecspi_reset,
586 	.devtype = IMX51_ECSPI,
587 };
588 
589 static struct platform_device_id spi_imx_devtype[] = {
590 	{
591 		.name = "imx1-cspi",
592 		.driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
593 	}, {
594 		.name = "imx21-cspi",
595 		.driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
596 	}, {
597 		.name = "imx27-cspi",
598 		.driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
599 	}, {
600 		.name = "imx31-cspi",
601 		.driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
602 	}, {
603 		.name = "imx35-cspi",
604 		.driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
605 	}, {
606 		.name = "imx51-ecspi",
607 		.driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
608 	}, {
609 		/* sentinel */
610 	}
611 };
612 
613 static const struct of_device_id spi_imx_dt_ids[] = {
614 	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
615 	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
616 	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
617 	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
618 	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
619 	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
620 	{ /* sentinel */ }
621 };
622 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
623 
624 static void spi_imx_chipselect(struct spi_device *spi, int is_active)
625 {
626 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
627 	int gpio = spi_imx->chipselect[spi->chip_select];
628 	int active = is_active != BITBANG_CS_INACTIVE;
629 	int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
630 
631 	if (!gpio_is_valid(gpio))
632 		return;
633 
634 	gpio_set_value(gpio, dev_is_lowactive ^ active);
635 }
636 
637 static void spi_imx_push(struct spi_imx_data *spi_imx)
638 {
639 	while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) {
640 		if (!spi_imx->count)
641 			break;
642 		spi_imx->tx(spi_imx);
643 		spi_imx->txfifo++;
644 	}
645 
646 	spi_imx->devtype_data->trigger(spi_imx);
647 }
648 
649 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
650 {
651 	struct spi_imx_data *spi_imx = dev_id;
652 
653 	while (spi_imx->devtype_data->rx_available(spi_imx)) {
654 		spi_imx->rx(spi_imx);
655 		spi_imx->txfifo--;
656 	}
657 
658 	if (spi_imx->count) {
659 		spi_imx_push(spi_imx);
660 		return IRQ_HANDLED;
661 	}
662 
663 	if (spi_imx->txfifo) {
664 		/* No data left to push, but still waiting for rx data,
665 		 * enable receive data available interrupt.
666 		 */
667 		spi_imx->devtype_data->intctrl(
668 				spi_imx, MXC_INT_RR);
669 		return IRQ_HANDLED;
670 	}
671 
672 	spi_imx->devtype_data->intctrl(spi_imx, 0);
673 	complete(&spi_imx->xfer_done);
674 
675 	return IRQ_HANDLED;
676 }
677 
678 static int spi_imx_setupxfer(struct spi_device *spi,
679 				 struct spi_transfer *t)
680 {
681 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
682 	struct spi_imx_config config;
683 
684 	config.bpw = t ? t->bits_per_word : spi->bits_per_word;
685 	config.speed_hz  = t ? t->speed_hz : spi->max_speed_hz;
686 	config.mode = spi->mode;
687 	config.cs = spi->chip_select;
688 
689 	if (!config.speed_hz)
690 		config.speed_hz = spi->max_speed_hz;
691 	if (!config.bpw)
692 		config.bpw = spi->bits_per_word;
693 
694 	/* Initialize the functions for transfer */
695 	if (config.bpw <= 8) {
696 		spi_imx->rx = spi_imx_buf_rx_u8;
697 		spi_imx->tx = spi_imx_buf_tx_u8;
698 	} else if (config.bpw <= 16) {
699 		spi_imx->rx = spi_imx_buf_rx_u16;
700 		spi_imx->tx = spi_imx_buf_tx_u16;
701 	} else {
702 		spi_imx->rx = spi_imx_buf_rx_u32;
703 		spi_imx->tx = spi_imx_buf_tx_u32;
704 	}
705 
706 	spi_imx->devtype_data->config(spi_imx, &config);
707 
708 	return 0;
709 }
710 
711 static int spi_imx_transfer(struct spi_device *spi,
712 				struct spi_transfer *transfer)
713 {
714 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
715 
716 	spi_imx->tx_buf = transfer->tx_buf;
717 	spi_imx->rx_buf = transfer->rx_buf;
718 	spi_imx->count = transfer->len;
719 	spi_imx->txfifo = 0;
720 
721 	init_completion(&spi_imx->xfer_done);
722 
723 	spi_imx_push(spi_imx);
724 
725 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
726 
727 	wait_for_completion(&spi_imx->xfer_done);
728 
729 	return transfer->len;
730 }
731 
732 static int spi_imx_setup(struct spi_device *spi)
733 {
734 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
735 	int gpio = spi_imx->chipselect[spi->chip_select];
736 
737 	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
738 		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
739 
740 	if (gpio_is_valid(gpio))
741 		gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
742 
743 	spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
744 
745 	return 0;
746 }
747 
748 static void spi_imx_cleanup(struct spi_device *spi)
749 {
750 }
751 
752 static int
753 spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
754 {
755 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
756 	int ret;
757 
758 	ret = clk_enable(spi_imx->clk_per);
759 	if (ret)
760 		return ret;
761 
762 	ret = clk_enable(spi_imx->clk_ipg);
763 	if (ret) {
764 		clk_disable(spi_imx->clk_per);
765 		return ret;
766 	}
767 
768 	return 0;
769 }
770 
771 static int
772 spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
773 {
774 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
775 
776 	clk_disable(spi_imx->clk_ipg);
777 	clk_disable(spi_imx->clk_per);
778 	return 0;
779 }
780 
781 static int spi_imx_probe(struct platform_device *pdev)
782 {
783 	struct device_node *np = pdev->dev.of_node;
784 	const struct of_device_id *of_id =
785 			of_match_device(spi_imx_dt_ids, &pdev->dev);
786 	struct spi_imx_master *mxc_platform_info =
787 			dev_get_platdata(&pdev->dev);
788 	struct spi_master *master;
789 	struct spi_imx_data *spi_imx;
790 	struct resource *res;
791 	int i, ret, num_cs;
792 
793 	if (!np && !mxc_platform_info) {
794 		dev_err(&pdev->dev, "can't get the platform data\n");
795 		return -EINVAL;
796 	}
797 
798 	ret = of_property_read_u32(np, "fsl,spi-num-chipselects", &num_cs);
799 	if (ret < 0) {
800 		if (mxc_platform_info)
801 			num_cs = mxc_platform_info->num_chipselect;
802 		else
803 			return ret;
804 	}
805 
806 	master = spi_alloc_master(&pdev->dev,
807 			sizeof(struct spi_imx_data) + sizeof(int) * num_cs);
808 	if (!master)
809 		return -ENOMEM;
810 
811 	platform_set_drvdata(pdev, master);
812 
813 	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
814 	master->bus_num = pdev->id;
815 	master->num_chipselect = num_cs;
816 
817 	spi_imx = spi_master_get_devdata(master);
818 	spi_imx->bitbang.master = master;
819 
820 	for (i = 0; i < master->num_chipselect; i++) {
821 		int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
822 		if (!gpio_is_valid(cs_gpio) && mxc_platform_info)
823 			cs_gpio = mxc_platform_info->chipselect[i];
824 
825 		spi_imx->chipselect[i] = cs_gpio;
826 		if (!gpio_is_valid(cs_gpio))
827 			continue;
828 
829 		ret = devm_gpio_request(&pdev->dev, spi_imx->chipselect[i],
830 					DRIVER_NAME);
831 		if (ret) {
832 			dev_err(&pdev->dev, "can't get cs gpios\n");
833 			goto out_master_put;
834 		}
835 	}
836 
837 	spi_imx->bitbang.chipselect = spi_imx_chipselect;
838 	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
839 	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
840 	spi_imx->bitbang.master->setup = spi_imx_setup;
841 	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
842 	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
843 	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
844 	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
845 
846 	init_completion(&spi_imx->xfer_done);
847 
848 	spi_imx->devtype_data = of_id ? of_id->data :
849 		(struct spi_imx_devtype_data *) pdev->id_entry->driver_data;
850 
851 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
852 	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
853 	if (IS_ERR(spi_imx->base)) {
854 		ret = PTR_ERR(spi_imx->base);
855 		goto out_master_put;
856 	}
857 
858 	spi_imx->irq = platform_get_irq(pdev, 0);
859 	if (spi_imx->irq < 0) {
860 		ret = -EINVAL;
861 		goto out_master_put;
862 	}
863 
864 	ret = devm_request_irq(&pdev->dev, spi_imx->irq, spi_imx_isr, 0,
865 			       DRIVER_NAME, spi_imx);
866 	if (ret) {
867 		dev_err(&pdev->dev, "can't get irq%d: %d\n", spi_imx->irq, ret);
868 		goto out_master_put;
869 	}
870 
871 	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
872 	if (IS_ERR(spi_imx->clk_ipg)) {
873 		ret = PTR_ERR(spi_imx->clk_ipg);
874 		goto out_master_put;
875 	}
876 
877 	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
878 	if (IS_ERR(spi_imx->clk_per)) {
879 		ret = PTR_ERR(spi_imx->clk_per);
880 		goto out_master_put;
881 	}
882 
883 	ret = clk_prepare_enable(spi_imx->clk_per);
884 	if (ret)
885 		goto out_master_put;
886 
887 	ret = clk_prepare_enable(spi_imx->clk_ipg);
888 	if (ret)
889 		goto out_put_per;
890 
891 	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
892 
893 	spi_imx->devtype_data->reset(spi_imx);
894 
895 	spi_imx->devtype_data->intctrl(spi_imx, 0);
896 
897 	master->dev.of_node = pdev->dev.of_node;
898 	ret = spi_bitbang_start(&spi_imx->bitbang);
899 	if (ret) {
900 		dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
901 		goto out_clk_put;
902 	}
903 
904 	dev_info(&pdev->dev, "probed\n");
905 
906 	clk_disable(spi_imx->clk_ipg);
907 	clk_disable(spi_imx->clk_per);
908 	return ret;
909 
910 out_clk_put:
911 	clk_disable_unprepare(spi_imx->clk_ipg);
912 out_put_per:
913 	clk_disable_unprepare(spi_imx->clk_per);
914 out_master_put:
915 	spi_master_put(master);
916 
917 	return ret;
918 }
919 
920 static int spi_imx_remove(struct platform_device *pdev)
921 {
922 	struct spi_master *master = platform_get_drvdata(pdev);
923 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
924 
925 	spi_bitbang_stop(&spi_imx->bitbang);
926 
927 	writel(0, spi_imx->base + MXC_CSPICTRL);
928 	clk_disable_unprepare(spi_imx->clk_ipg);
929 	clk_disable_unprepare(spi_imx->clk_per);
930 	spi_master_put(master);
931 
932 	return 0;
933 }
934 
935 static struct platform_driver spi_imx_driver = {
936 	.driver = {
937 		   .name = DRIVER_NAME,
938 		   .owner = THIS_MODULE,
939 		   .of_match_table = spi_imx_dt_ids,
940 		   },
941 	.id_table = spi_imx_devtype,
942 	.probe = spi_imx_probe,
943 	.remove = spi_imx_remove,
944 };
945 module_platform_driver(spi_imx_driver);
946 
947 MODULE_DESCRIPTION("SPI Master Controller driver");
948 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
949 MODULE_LICENSE("GPL");
950 MODULE_ALIAS("platform:" DRIVER_NAME);
951