xref: /openbmc/linux/drivers/spi/spi-imx.c (revision 95e9fd10)
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 #include <linux/pinctrl/consumer.h>
41 
42 #include <mach/spi.h>
43 
44 #define DRIVER_NAME "spi_imx"
45 
46 #define MXC_CSPIRXDATA		0x00
47 #define MXC_CSPITXDATA		0x04
48 #define MXC_CSPICTRL		0x08
49 #define MXC_CSPIINT		0x0c
50 #define MXC_RESET		0x1c
51 
52 /* generic defines to abstract from the different register layouts */
53 #define MXC_INT_RR	(1 << 0) /* Receive data ready interrupt */
54 #define MXC_INT_TE	(1 << 1) /* Transmit FIFO empty interrupt */
55 
56 struct spi_imx_config {
57 	unsigned int speed_hz;
58 	unsigned int bpw;
59 	unsigned int mode;
60 	u8 cs;
61 };
62 
63 enum spi_imx_devtype {
64 	IMX1_CSPI,
65 	IMX21_CSPI,
66 	IMX27_CSPI,
67 	IMX31_CSPI,
68 	IMX35_CSPI,	/* CSPI on all i.mx except above */
69 	IMX51_ECSPI,	/* ECSPI on i.mx51 and later */
70 };
71 
72 struct spi_imx_data;
73 
74 struct spi_imx_devtype_data {
75 	void (*intctrl)(struct spi_imx_data *, int);
76 	int (*config)(struct spi_imx_data *, struct spi_imx_config *);
77 	void (*trigger)(struct spi_imx_data *);
78 	int (*rx_available)(struct spi_imx_data *);
79 	void (*reset)(struct spi_imx_data *);
80 	enum spi_imx_devtype devtype;
81 };
82 
83 struct spi_imx_data {
84 	struct spi_bitbang bitbang;
85 
86 	struct completion xfer_done;
87 	void __iomem *base;
88 	int irq;
89 	struct clk *clk_per;
90 	struct clk *clk_ipg;
91 	unsigned long spi_clk;
92 
93 	unsigned int count;
94 	void (*tx)(struct spi_imx_data *);
95 	void (*rx)(struct spi_imx_data *);
96 	void *rx_buf;
97 	const void *tx_buf;
98 	unsigned int txfifo; /* number of words pushed in tx FIFO */
99 
100 	struct spi_imx_devtype_data *devtype_data;
101 	int chipselect[0];
102 };
103 
104 static inline int is_imx27_cspi(struct spi_imx_data *d)
105 {
106 	return d->devtype_data->devtype == IMX27_CSPI;
107 }
108 
109 static inline int is_imx35_cspi(struct spi_imx_data *d)
110 {
111 	return d->devtype_data->devtype == IMX35_CSPI;
112 }
113 
114 static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d)
115 {
116 	return (d->devtype_data->devtype == IMX51_ECSPI) ? 64 : 8;
117 }
118 
119 #define MXC_SPI_BUF_RX(type)						\
120 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
121 {									\
122 	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
123 									\
124 	if (spi_imx->rx_buf) {						\
125 		*(type *)spi_imx->rx_buf = val;				\
126 		spi_imx->rx_buf += sizeof(type);			\
127 	}								\
128 }
129 
130 #define MXC_SPI_BUF_TX(type)						\
131 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
132 {									\
133 	type val = 0;							\
134 									\
135 	if (spi_imx->tx_buf) {						\
136 		val = *(type *)spi_imx->tx_buf;				\
137 		spi_imx->tx_buf += sizeof(type);			\
138 	}								\
139 									\
140 	spi_imx->count -= sizeof(type);					\
141 									\
142 	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
143 }
144 
145 MXC_SPI_BUF_RX(u8)
146 MXC_SPI_BUF_TX(u8)
147 MXC_SPI_BUF_RX(u16)
148 MXC_SPI_BUF_TX(u16)
149 MXC_SPI_BUF_RX(u32)
150 MXC_SPI_BUF_TX(u32)
151 
152 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
153  * (which is currently not the case in this driver)
154  */
155 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
156 	256, 384, 512, 768, 1024};
157 
158 /* MX21, MX27 */
159 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
160 		unsigned int fspi, unsigned int max)
161 {
162 	int i;
163 
164 	for (i = 2; i < max; i++)
165 		if (fspi * mxc_clkdivs[i] >= fin)
166 			return i;
167 
168 	return max;
169 }
170 
171 /* MX1, MX31, MX35, MX51 CSPI */
172 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
173 		unsigned int fspi)
174 {
175 	int i, div = 4;
176 
177 	for (i = 0; i < 7; i++) {
178 		if (fspi * div >= fin)
179 			return i;
180 		div <<= 1;
181 	}
182 
183 	return 7;
184 }
185 
186 #define MX51_ECSPI_CTRL		0x08
187 #define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
188 #define MX51_ECSPI_CTRL_XCH		(1 <<  2)
189 #define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
190 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
191 #define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
192 #define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
193 #define MX51_ECSPI_CTRL_BL_OFFSET	20
194 
195 #define MX51_ECSPI_CONFIG	0x0c
196 #define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
197 #define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
198 #define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
199 #define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
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 
293 	if (config->mode & SPI_CS_HIGH)
294 		cfg |= MX51_ECSPI_CONFIG_SSBPOL(config->cs);
295 
296 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
297 	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
298 
299 	return 0;
300 }
301 
302 static int __maybe_unused mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
303 {
304 	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
305 }
306 
307 static void __maybe_unused mx51_ecspi_reset(struct spi_imx_data *spi_imx)
308 {
309 	/* drain receive buffer */
310 	while (mx51_ecspi_rx_available(spi_imx))
311 		readl(spi_imx->base + MXC_CSPIRXDATA);
312 }
313 
314 #define MX31_INTREG_TEEN	(1 << 0)
315 #define MX31_INTREG_RREN	(1 << 3)
316 
317 #define MX31_CSPICTRL_ENABLE	(1 << 0)
318 #define MX31_CSPICTRL_MASTER	(1 << 1)
319 #define MX31_CSPICTRL_XCH	(1 << 2)
320 #define MX31_CSPICTRL_POL	(1 << 4)
321 #define MX31_CSPICTRL_PHA	(1 << 5)
322 #define MX31_CSPICTRL_SSCTL	(1 << 6)
323 #define MX31_CSPICTRL_SSPOL	(1 << 7)
324 #define MX31_CSPICTRL_BC_SHIFT	8
325 #define MX35_CSPICTRL_BL_SHIFT	20
326 #define MX31_CSPICTRL_CS_SHIFT	24
327 #define MX35_CSPICTRL_CS_SHIFT	12
328 #define MX31_CSPICTRL_DR_SHIFT	16
329 
330 #define MX31_CSPISTATUS		0x14
331 #define MX31_STATUS_RR		(1 << 3)
332 
333 /* These functions also work for the i.MX35, but be aware that
334  * the i.MX35 has a slightly different register layout for bits
335  * we do not use here.
336  */
337 static void __maybe_unused mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
338 {
339 	unsigned int val = 0;
340 
341 	if (enable & MXC_INT_TE)
342 		val |= MX31_INTREG_TEEN;
343 	if (enable & MXC_INT_RR)
344 		val |= MX31_INTREG_RREN;
345 
346 	writel(val, spi_imx->base + MXC_CSPIINT);
347 }
348 
349 static void __maybe_unused mx31_trigger(struct spi_imx_data *spi_imx)
350 {
351 	unsigned int reg;
352 
353 	reg = readl(spi_imx->base + MXC_CSPICTRL);
354 	reg |= MX31_CSPICTRL_XCH;
355 	writel(reg, spi_imx->base + MXC_CSPICTRL);
356 }
357 
358 static int __maybe_unused mx31_config(struct spi_imx_data *spi_imx,
359 		struct spi_imx_config *config)
360 {
361 	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
362 	int cs = spi_imx->chipselect[config->cs];
363 
364 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
365 		MX31_CSPICTRL_DR_SHIFT;
366 
367 	if (is_imx35_cspi(spi_imx)) {
368 		reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT;
369 		reg |= MX31_CSPICTRL_SSCTL;
370 	} else {
371 		reg |= (config->bpw - 1) << MX31_CSPICTRL_BC_SHIFT;
372 	}
373 
374 	if (config->mode & SPI_CPHA)
375 		reg |= MX31_CSPICTRL_PHA;
376 	if (config->mode & SPI_CPOL)
377 		reg |= MX31_CSPICTRL_POL;
378 	if (config->mode & SPI_CS_HIGH)
379 		reg |= MX31_CSPICTRL_SSPOL;
380 	if (cs < 0)
381 		reg |= (cs + 32) <<
382 			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
383 						  MX31_CSPICTRL_CS_SHIFT);
384 
385 	writel(reg, spi_imx->base + MXC_CSPICTRL);
386 
387 	return 0;
388 }
389 
390 static int __maybe_unused mx31_rx_available(struct spi_imx_data *spi_imx)
391 {
392 	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
393 }
394 
395 static void __maybe_unused mx31_reset(struct spi_imx_data *spi_imx)
396 {
397 	/* drain receive buffer */
398 	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
399 		readl(spi_imx->base + MXC_CSPIRXDATA);
400 }
401 
402 #define MX21_INTREG_RR		(1 << 4)
403 #define MX21_INTREG_TEEN	(1 << 9)
404 #define MX21_INTREG_RREN	(1 << 13)
405 
406 #define MX21_CSPICTRL_POL	(1 << 5)
407 #define MX21_CSPICTRL_PHA	(1 << 6)
408 #define MX21_CSPICTRL_SSPOL	(1 << 8)
409 #define MX21_CSPICTRL_XCH	(1 << 9)
410 #define MX21_CSPICTRL_ENABLE	(1 << 10)
411 #define MX21_CSPICTRL_MASTER	(1 << 11)
412 #define MX21_CSPICTRL_DR_SHIFT	14
413 #define MX21_CSPICTRL_CS_SHIFT	19
414 
415 static void __maybe_unused mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
416 {
417 	unsigned int val = 0;
418 
419 	if (enable & MXC_INT_TE)
420 		val |= MX21_INTREG_TEEN;
421 	if (enable & MXC_INT_RR)
422 		val |= MX21_INTREG_RREN;
423 
424 	writel(val, spi_imx->base + MXC_CSPIINT);
425 }
426 
427 static void __maybe_unused mx21_trigger(struct spi_imx_data *spi_imx)
428 {
429 	unsigned int reg;
430 
431 	reg = readl(spi_imx->base + MXC_CSPICTRL);
432 	reg |= MX21_CSPICTRL_XCH;
433 	writel(reg, spi_imx->base + MXC_CSPICTRL);
434 }
435 
436 static int __maybe_unused mx21_config(struct spi_imx_data *spi_imx,
437 		struct spi_imx_config *config)
438 {
439 	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
440 	int cs = spi_imx->chipselect[config->cs];
441 	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
442 
443 	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max) <<
444 		MX21_CSPICTRL_DR_SHIFT;
445 	reg |= config->bpw - 1;
446 
447 	if (config->mode & SPI_CPHA)
448 		reg |= MX21_CSPICTRL_PHA;
449 	if (config->mode & SPI_CPOL)
450 		reg |= MX21_CSPICTRL_POL;
451 	if (config->mode & SPI_CS_HIGH)
452 		reg |= MX21_CSPICTRL_SSPOL;
453 	if (cs < 0)
454 		reg |= (cs + 32) << MX21_CSPICTRL_CS_SHIFT;
455 
456 	writel(reg, spi_imx->base + MXC_CSPICTRL);
457 
458 	return 0;
459 }
460 
461 static int __maybe_unused mx21_rx_available(struct spi_imx_data *spi_imx)
462 {
463 	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
464 }
465 
466 static void __maybe_unused mx21_reset(struct spi_imx_data *spi_imx)
467 {
468 	writel(1, spi_imx->base + MXC_RESET);
469 }
470 
471 #define MX1_INTREG_RR		(1 << 3)
472 #define MX1_INTREG_TEEN		(1 << 8)
473 #define MX1_INTREG_RREN		(1 << 11)
474 
475 #define MX1_CSPICTRL_POL	(1 << 4)
476 #define MX1_CSPICTRL_PHA	(1 << 5)
477 #define MX1_CSPICTRL_XCH	(1 << 8)
478 #define MX1_CSPICTRL_ENABLE	(1 << 9)
479 #define MX1_CSPICTRL_MASTER	(1 << 10)
480 #define MX1_CSPICTRL_DR_SHIFT	13
481 
482 static void __maybe_unused mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
483 {
484 	unsigned int val = 0;
485 
486 	if (enable & MXC_INT_TE)
487 		val |= MX1_INTREG_TEEN;
488 	if (enable & MXC_INT_RR)
489 		val |= MX1_INTREG_RREN;
490 
491 	writel(val, spi_imx->base + MXC_CSPIINT);
492 }
493 
494 static void __maybe_unused mx1_trigger(struct spi_imx_data *spi_imx)
495 {
496 	unsigned int reg;
497 
498 	reg = readl(spi_imx->base + MXC_CSPICTRL);
499 	reg |= MX1_CSPICTRL_XCH;
500 	writel(reg, spi_imx->base + MXC_CSPICTRL);
501 }
502 
503 static int __maybe_unused mx1_config(struct spi_imx_data *spi_imx,
504 		struct spi_imx_config *config)
505 {
506 	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
507 
508 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
509 		MX1_CSPICTRL_DR_SHIFT;
510 	reg |= config->bpw - 1;
511 
512 	if (config->mode & SPI_CPHA)
513 		reg |= MX1_CSPICTRL_PHA;
514 	if (config->mode & SPI_CPOL)
515 		reg |= MX1_CSPICTRL_POL;
516 
517 	writel(reg, spi_imx->base + MXC_CSPICTRL);
518 
519 	return 0;
520 }
521 
522 static int __maybe_unused mx1_rx_available(struct spi_imx_data *spi_imx)
523 {
524 	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
525 }
526 
527 static void __maybe_unused mx1_reset(struct spi_imx_data *spi_imx)
528 {
529 	writel(1, spi_imx->base + MXC_RESET);
530 }
531 
532 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
533 	.intctrl = mx1_intctrl,
534 	.config = mx1_config,
535 	.trigger = mx1_trigger,
536 	.rx_available = mx1_rx_available,
537 	.reset = mx1_reset,
538 	.devtype = IMX1_CSPI,
539 };
540 
541 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
542 	.intctrl = mx21_intctrl,
543 	.config = mx21_config,
544 	.trigger = mx21_trigger,
545 	.rx_available = mx21_rx_available,
546 	.reset = mx21_reset,
547 	.devtype = IMX21_CSPI,
548 };
549 
550 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
551 	/* i.mx27 cspi shares the functions with i.mx21 one */
552 	.intctrl = mx21_intctrl,
553 	.config = mx21_config,
554 	.trigger = mx21_trigger,
555 	.rx_available = mx21_rx_available,
556 	.reset = mx21_reset,
557 	.devtype = IMX27_CSPI,
558 };
559 
560 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
561 	.intctrl = mx31_intctrl,
562 	.config = mx31_config,
563 	.trigger = mx31_trigger,
564 	.rx_available = mx31_rx_available,
565 	.reset = mx31_reset,
566 	.devtype = IMX31_CSPI,
567 };
568 
569 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
570 	/* i.mx35 and later cspi shares the functions with i.mx31 one */
571 	.intctrl = mx31_intctrl,
572 	.config = mx31_config,
573 	.trigger = mx31_trigger,
574 	.rx_available = mx31_rx_available,
575 	.reset = mx31_reset,
576 	.devtype = IMX35_CSPI,
577 };
578 
579 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
580 	.intctrl = mx51_ecspi_intctrl,
581 	.config = mx51_ecspi_config,
582 	.trigger = mx51_ecspi_trigger,
583 	.rx_available = mx51_ecspi_rx_available,
584 	.reset = mx51_ecspi_reset,
585 	.devtype = IMX51_ECSPI,
586 };
587 
588 static struct platform_device_id spi_imx_devtype[] = {
589 	{
590 		.name = "imx1-cspi",
591 		.driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
592 	}, {
593 		.name = "imx21-cspi",
594 		.driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
595 	}, {
596 		.name = "imx27-cspi",
597 		.driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
598 	}, {
599 		.name = "imx31-cspi",
600 		.driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
601 	}, {
602 		.name = "imx35-cspi",
603 		.driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
604 	}, {
605 		.name = "imx51-ecspi",
606 		.driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
607 	}, {
608 		/* sentinel */
609 	}
610 };
611 
612 static const struct of_device_id spi_imx_dt_ids[] = {
613 	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
614 	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
615 	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
616 	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
617 	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
618 	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
619 	{ /* sentinel */ }
620 };
621 
622 static void spi_imx_chipselect(struct spi_device *spi, int is_active)
623 {
624 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
625 	int gpio = spi_imx->chipselect[spi->chip_select];
626 	int active = is_active != BITBANG_CS_INACTIVE;
627 	int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
628 
629 	if (!gpio_is_valid(gpio))
630 		return;
631 
632 	gpio_set_value(gpio, dev_is_lowactive ^ active);
633 }
634 
635 static void spi_imx_push(struct spi_imx_data *spi_imx)
636 {
637 	while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) {
638 		if (!spi_imx->count)
639 			break;
640 		spi_imx->tx(spi_imx);
641 		spi_imx->txfifo++;
642 	}
643 
644 	spi_imx->devtype_data->trigger(spi_imx);
645 }
646 
647 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
648 {
649 	struct spi_imx_data *spi_imx = dev_id;
650 
651 	while (spi_imx->devtype_data->rx_available(spi_imx)) {
652 		spi_imx->rx(spi_imx);
653 		spi_imx->txfifo--;
654 	}
655 
656 	if (spi_imx->count) {
657 		spi_imx_push(spi_imx);
658 		return IRQ_HANDLED;
659 	}
660 
661 	if (spi_imx->txfifo) {
662 		/* No data left to push, but still waiting for rx data,
663 		 * enable receive data available interrupt.
664 		 */
665 		spi_imx->devtype_data->intctrl(
666 				spi_imx, MXC_INT_RR);
667 		return IRQ_HANDLED;
668 	}
669 
670 	spi_imx->devtype_data->intctrl(spi_imx, 0);
671 	complete(&spi_imx->xfer_done);
672 
673 	return IRQ_HANDLED;
674 }
675 
676 static int spi_imx_setupxfer(struct spi_device *spi,
677 				 struct spi_transfer *t)
678 {
679 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
680 	struct spi_imx_config config;
681 
682 	config.bpw = t ? t->bits_per_word : spi->bits_per_word;
683 	config.speed_hz  = t ? t->speed_hz : spi->max_speed_hz;
684 	config.mode = spi->mode;
685 	config.cs = spi->chip_select;
686 
687 	if (!config.speed_hz)
688 		config.speed_hz = spi->max_speed_hz;
689 	if (!config.bpw)
690 		config.bpw = spi->bits_per_word;
691 
692 	/* Initialize the functions for transfer */
693 	if (config.bpw <= 8) {
694 		spi_imx->rx = spi_imx_buf_rx_u8;
695 		spi_imx->tx = spi_imx_buf_tx_u8;
696 	} else if (config.bpw <= 16) {
697 		spi_imx->rx = spi_imx_buf_rx_u16;
698 		spi_imx->tx = spi_imx_buf_tx_u16;
699 	} else if (config.bpw <= 32) {
700 		spi_imx->rx = spi_imx_buf_rx_u32;
701 		spi_imx->tx = spi_imx_buf_tx_u32;
702 	} else
703 		BUG();
704 
705 	spi_imx->devtype_data->config(spi_imx, &config);
706 
707 	return 0;
708 }
709 
710 static int spi_imx_transfer(struct spi_device *spi,
711 				struct spi_transfer *transfer)
712 {
713 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
714 
715 	spi_imx->tx_buf = transfer->tx_buf;
716 	spi_imx->rx_buf = transfer->rx_buf;
717 	spi_imx->count = transfer->len;
718 	spi_imx->txfifo = 0;
719 
720 	init_completion(&spi_imx->xfer_done);
721 
722 	spi_imx_push(spi_imx);
723 
724 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
725 
726 	wait_for_completion(&spi_imx->xfer_done);
727 
728 	return transfer->len;
729 }
730 
731 static int spi_imx_setup(struct spi_device *spi)
732 {
733 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
734 	int gpio = spi_imx->chipselect[spi->chip_select];
735 
736 	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
737 		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
738 
739 	if (gpio_is_valid(gpio))
740 		gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
741 
742 	spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
743 
744 	return 0;
745 }
746 
747 static void spi_imx_cleanup(struct spi_device *spi)
748 {
749 }
750 
751 static int __devinit spi_imx_probe(struct platform_device *pdev)
752 {
753 	struct device_node *np = pdev->dev.of_node;
754 	const struct of_device_id *of_id =
755 			of_match_device(spi_imx_dt_ids, &pdev->dev);
756 	struct spi_imx_master *mxc_platform_info =
757 			dev_get_platdata(&pdev->dev);
758 	struct spi_master *master;
759 	struct spi_imx_data *spi_imx;
760 	struct resource *res;
761 	struct pinctrl *pinctrl;
762 	int i, ret, num_cs;
763 
764 	if (!np && !mxc_platform_info) {
765 		dev_err(&pdev->dev, "can't get the platform data\n");
766 		return -EINVAL;
767 	}
768 
769 	ret = of_property_read_u32(np, "fsl,spi-num-chipselects", &num_cs);
770 	if (ret < 0) {
771 		if (mxc_platform_info)
772 			num_cs = mxc_platform_info->num_chipselect;
773 		else
774 			return ret;
775 	}
776 
777 	master = spi_alloc_master(&pdev->dev,
778 			sizeof(struct spi_imx_data) + sizeof(int) * num_cs);
779 	if (!master)
780 		return -ENOMEM;
781 
782 	platform_set_drvdata(pdev, master);
783 
784 	master->bus_num = pdev->id;
785 	master->num_chipselect = num_cs;
786 
787 	spi_imx = spi_master_get_devdata(master);
788 	spi_imx->bitbang.master = spi_master_get(master);
789 
790 	for (i = 0; i < master->num_chipselect; i++) {
791 		int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
792 		if (!gpio_is_valid(cs_gpio) && mxc_platform_info)
793 			cs_gpio = mxc_platform_info->chipselect[i];
794 
795 		spi_imx->chipselect[i] = cs_gpio;
796 		if (!gpio_is_valid(cs_gpio))
797 			continue;
798 
799 		ret = gpio_request(spi_imx->chipselect[i], DRIVER_NAME);
800 		if (ret) {
801 			dev_err(&pdev->dev, "can't get cs gpios\n");
802 			goto out_gpio_free;
803 		}
804 	}
805 
806 	spi_imx->bitbang.chipselect = spi_imx_chipselect;
807 	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
808 	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
809 	spi_imx->bitbang.master->setup = spi_imx_setup;
810 	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
811 	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
812 
813 	init_completion(&spi_imx->xfer_done);
814 
815 	spi_imx->devtype_data = of_id ? of_id->data :
816 		(struct spi_imx_devtype_data *) pdev->id_entry->driver_data;
817 
818 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
819 	if (!res) {
820 		dev_err(&pdev->dev, "can't get platform resource\n");
821 		ret = -ENOMEM;
822 		goto out_gpio_free;
823 	}
824 
825 	if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
826 		dev_err(&pdev->dev, "request_mem_region failed\n");
827 		ret = -EBUSY;
828 		goto out_gpio_free;
829 	}
830 
831 	spi_imx->base = ioremap(res->start, resource_size(res));
832 	if (!spi_imx->base) {
833 		ret = -EINVAL;
834 		goto out_release_mem;
835 	}
836 
837 	spi_imx->irq = platform_get_irq(pdev, 0);
838 	if (spi_imx->irq < 0) {
839 		ret = -EINVAL;
840 		goto out_iounmap;
841 	}
842 
843 	ret = request_irq(spi_imx->irq, spi_imx_isr, 0, DRIVER_NAME, spi_imx);
844 	if (ret) {
845 		dev_err(&pdev->dev, "can't get irq%d: %d\n", spi_imx->irq, ret);
846 		goto out_iounmap;
847 	}
848 
849 	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
850 	if (IS_ERR(pinctrl)) {
851 		ret = PTR_ERR(pinctrl);
852 		goto out_free_irq;
853 	}
854 
855 	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
856 	if (IS_ERR(spi_imx->clk_ipg)) {
857 		ret = PTR_ERR(spi_imx->clk_ipg);
858 		goto out_free_irq;
859 	}
860 
861 	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
862 	if (IS_ERR(spi_imx->clk_per)) {
863 		ret = PTR_ERR(spi_imx->clk_per);
864 		goto out_free_irq;
865 	}
866 
867 	clk_prepare_enable(spi_imx->clk_per);
868 	clk_prepare_enable(spi_imx->clk_ipg);
869 
870 	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
871 
872 	spi_imx->devtype_data->reset(spi_imx);
873 
874 	spi_imx->devtype_data->intctrl(spi_imx, 0);
875 
876 	master->dev.of_node = pdev->dev.of_node;
877 	ret = spi_bitbang_start(&spi_imx->bitbang);
878 	if (ret) {
879 		dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
880 		goto out_clk_put;
881 	}
882 
883 	dev_info(&pdev->dev, "probed\n");
884 
885 	return ret;
886 
887 out_clk_put:
888 	clk_disable_unprepare(spi_imx->clk_per);
889 	clk_disable_unprepare(spi_imx->clk_ipg);
890 out_free_irq:
891 	free_irq(spi_imx->irq, spi_imx);
892 out_iounmap:
893 	iounmap(spi_imx->base);
894 out_release_mem:
895 	release_mem_region(res->start, resource_size(res));
896 out_gpio_free:
897 	while (--i >= 0) {
898 		if (gpio_is_valid(spi_imx->chipselect[i]))
899 			gpio_free(spi_imx->chipselect[i]);
900 	}
901 	spi_master_put(master);
902 	kfree(master);
903 	platform_set_drvdata(pdev, NULL);
904 	return ret;
905 }
906 
907 static int __devexit spi_imx_remove(struct platform_device *pdev)
908 {
909 	struct spi_master *master = platform_get_drvdata(pdev);
910 	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
911 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
912 	int i;
913 
914 	spi_bitbang_stop(&spi_imx->bitbang);
915 
916 	writel(0, spi_imx->base + MXC_CSPICTRL);
917 	clk_disable_unprepare(spi_imx->clk_per);
918 	clk_disable_unprepare(spi_imx->clk_ipg);
919 	free_irq(spi_imx->irq, spi_imx);
920 	iounmap(spi_imx->base);
921 
922 	for (i = 0; i < master->num_chipselect; i++)
923 		if (gpio_is_valid(spi_imx->chipselect[i]))
924 			gpio_free(spi_imx->chipselect[i]);
925 
926 	spi_master_put(master);
927 
928 	release_mem_region(res->start, resource_size(res));
929 
930 	platform_set_drvdata(pdev, NULL);
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 = __devexit_p(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