xref: /openbmc/linux/drivers/spi/spi-imx.c (revision 3a9a231d)
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 <mach/spi.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 *base;
87 	int irq;
88 	struct clk *clk;
89 	unsigned long spi_clk;
90 
91 	unsigned int count;
92 	void (*tx)(struct spi_imx_data *);
93 	void (*rx)(struct spi_imx_data *);
94 	void *rx_buf;
95 	const void *tx_buf;
96 	unsigned int txfifo; /* number of words pushed in tx FIFO */
97 
98 	struct spi_imx_devtype_data *devtype_data;
99 	int chipselect[0];
100 };
101 
102 static inline int is_imx27_cspi(struct spi_imx_data *d)
103 {
104 	return d->devtype_data->devtype == IMX27_CSPI;
105 }
106 
107 static inline int is_imx35_cspi(struct spi_imx_data *d)
108 {
109 	return d->devtype_data->devtype == IMX35_CSPI;
110 }
111 
112 static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d)
113 {
114 	return (d->devtype_data->devtype == IMX51_ECSPI) ? 64 : 8;
115 }
116 
117 #define MXC_SPI_BUF_RX(type)						\
118 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
119 {									\
120 	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
121 									\
122 	if (spi_imx->rx_buf) {						\
123 		*(type *)spi_imx->rx_buf = val;				\
124 		spi_imx->rx_buf += sizeof(type);			\
125 	}								\
126 }
127 
128 #define MXC_SPI_BUF_TX(type)						\
129 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
130 {									\
131 	type val = 0;							\
132 									\
133 	if (spi_imx->tx_buf) {						\
134 		val = *(type *)spi_imx->tx_buf;				\
135 		spi_imx->tx_buf += sizeof(type);			\
136 	}								\
137 									\
138 	spi_imx->count -= sizeof(type);					\
139 									\
140 	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
141 }
142 
143 MXC_SPI_BUF_RX(u8)
144 MXC_SPI_BUF_TX(u8)
145 MXC_SPI_BUF_RX(u16)
146 MXC_SPI_BUF_TX(u16)
147 MXC_SPI_BUF_RX(u32)
148 MXC_SPI_BUF_TX(u32)
149 
150 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
151  * (which is currently not the case in this driver)
152  */
153 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
154 	256, 384, 512, 768, 1024};
155 
156 /* MX21, MX27 */
157 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
158 		unsigned int fspi, unsigned int max)
159 {
160 	int i;
161 
162 	for (i = 2; i < max; i++)
163 		if (fspi * mxc_clkdivs[i] >= fin)
164 			return i;
165 
166 	return max;
167 }
168 
169 /* MX1, MX31, MX35, MX51 CSPI */
170 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
171 		unsigned int fspi)
172 {
173 	int i, div = 4;
174 
175 	for (i = 0; i < 7; i++) {
176 		if (fspi * div >= fin)
177 			return i;
178 		div <<= 1;
179 	}
180 
181 	return 7;
182 }
183 
184 #define MX51_ECSPI_CTRL		0x08
185 #define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
186 #define MX51_ECSPI_CTRL_XCH		(1 <<  2)
187 #define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
188 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
189 #define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
190 #define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
191 #define MX51_ECSPI_CTRL_BL_OFFSET	20
192 
193 #define MX51_ECSPI_CONFIG	0x0c
194 #define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
195 #define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
196 #define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
197 #define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
198 
199 #define MX51_ECSPI_INT		0x10
200 #define MX51_ECSPI_INT_TEEN		(1 <<  0)
201 #define MX51_ECSPI_INT_RREN		(1 <<  3)
202 
203 #define MX51_ECSPI_STAT		0x18
204 #define MX51_ECSPI_STAT_RR		(1 <<  3)
205 
206 /* MX51 eCSPI */
207 static unsigned int mx51_ecspi_clkdiv(unsigned int fin, unsigned int fspi)
208 {
209 	/*
210 	 * there are two 4-bit dividers, the pre-divider divides by
211 	 * $pre, the post-divider by 2^$post
212 	 */
213 	unsigned int pre, post;
214 
215 	if (unlikely(fspi > fin))
216 		return 0;
217 
218 	post = fls(fin) - fls(fspi);
219 	if (fin > fspi << post)
220 		post++;
221 
222 	/* now we have: (fin <= fspi << post) with post being minimal */
223 
224 	post = max(4U, post) - 4;
225 	if (unlikely(post > 0xf)) {
226 		pr_err("%s: cannot set clock freq: %u (base freq: %u)\n",
227 				__func__, fspi, fin);
228 		return 0xff;
229 	}
230 
231 	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
232 
233 	pr_debug("%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
234 			__func__, fin, fspi, post, pre);
235 	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
236 		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
237 }
238 
239 static void __maybe_unused mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
240 {
241 	unsigned val = 0;
242 
243 	if (enable & MXC_INT_TE)
244 		val |= MX51_ECSPI_INT_TEEN;
245 
246 	if (enable & MXC_INT_RR)
247 		val |= MX51_ECSPI_INT_RREN;
248 
249 	writel(val, spi_imx->base + MX51_ECSPI_INT);
250 }
251 
252 static void __maybe_unused mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
253 {
254 	u32 reg;
255 
256 	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
257 	reg |= MX51_ECSPI_CTRL_XCH;
258 	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
259 }
260 
261 static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx,
262 		struct spi_imx_config *config)
263 {
264 	u32 ctrl = MX51_ECSPI_CTRL_ENABLE, cfg = 0;
265 
266 	/*
267 	 * The hardware seems to have a race condition when changing modes. The
268 	 * current assumption is that the selection of the channel arrives
269 	 * earlier in the hardware than the mode bits when they are written at
270 	 * the same time.
271 	 * So set master mode for all channels as we do not support slave mode.
272 	 */
273 	ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
274 
275 	/* set clock speed */
276 	ctrl |= mx51_ecspi_clkdiv(spi_imx->spi_clk, config->speed_hz);
277 
278 	/* set chip select to use */
279 	ctrl |= MX51_ECSPI_CTRL_CS(config->cs);
280 
281 	ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET;
282 
283 	cfg |= MX51_ECSPI_CONFIG_SBBCTRL(config->cs);
284 
285 	if (config->mode & SPI_CPHA)
286 		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(config->cs);
287 
288 	if (config->mode & SPI_CPOL)
289 		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(config->cs);
290 
291 	if (config->mode & SPI_CS_HIGH)
292 		cfg |= MX51_ECSPI_CONFIG_SSBPOL(config->cs);
293 
294 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
295 	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
296 
297 	return 0;
298 }
299 
300 static int __maybe_unused mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
301 {
302 	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
303 }
304 
305 static void __maybe_unused mx51_ecspi_reset(struct spi_imx_data *spi_imx)
306 {
307 	/* drain receive buffer */
308 	while (mx51_ecspi_rx_available(spi_imx))
309 		readl(spi_imx->base + MXC_CSPIRXDATA);
310 }
311 
312 #define MX31_INTREG_TEEN	(1 << 0)
313 #define MX31_INTREG_RREN	(1 << 3)
314 
315 #define MX31_CSPICTRL_ENABLE	(1 << 0)
316 #define MX31_CSPICTRL_MASTER	(1 << 1)
317 #define MX31_CSPICTRL_XCH	(1 << 2)
318 #define MX31_CSPICTRL_POL	(1 << 4)
319 #define MX31_CSPICTRL_PHA	(1 << 5)
320 #define MX31_CSPICTRL_SSCTL	(1 << 6)
321 #define MX31_CSPICTRL_SSPOL	(1 << 7)
322 #define MX31_CSPICTRL_BC_SHIFT	8
323 #define MX35_CSPICTRL_BL_SHIFT	20
324 #define MX31_CSPICTRL_CS_SHIFT	24
325 #define MX35_CSPICTRL_CS_SHIFT	12
326 #define MX31_CSPICTRL_DR_SHIFT	16
327 
328 #define MX31_CSPISTATUS		0x14
329 #define MX31_STATUS_RR		(1 << 3)
330 
331 /* These functions also work for the i.MX35, but be aware that
332  * the i.MX35 has a slightly different register layout for bits
333  * we do not use here.
334  */
335 static void __maybe_unused mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
336 {
337 	unsigned int val = 0;
338 
339 	if (enable & MXC_INT_TE)
340 		val |= MX31_INTREG_TEEN;
341 	if (enable & MXC_INT_RR)
342 		val |= MX31_INTREG_RREN;
343 
344 	writel(val, spi_imx->base + MXC_CSPIINT);
345 }
346 
347 static void __maybe_unused mx31_trigger(struct spi_imx_data *spi_imx)
348 {
349 	unsigned int reg;
350 
351 	reg = readl(spi_imx->base + MXC_CSPICTRL);
352 	reg |= MX31_CSPICTRL_XCH;
353 	writel(reg, spi_imx->base + MXC_CSPICTRL);
354 }
355 
356 static int __maybe_unused mx31_config(struct spi_imx_data *spi_imx,
357 		struct spi_imx_config *config)
358 {
359 	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
360 	int cs = spi_imx->chipselect[config->cs];
361 
362 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
363 		MX31_CSPICTRL_DR_SHIFT;
364 
365 	if (is_imx35_cspi(spi_imx)) {
366 		reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT;
367 		reg |= MX31_CSPICTRL_SSCTL;
368 	} else {
369 		reg |= (config->bpw - 1) << MX31_CSPICTRL_BC_SHIFT;
370 	}
371 
372 	if (config->mode & SPI_CPHA)
373 		reg |= MX31_CSPICTRL_PHA;
374 	if (config->mode & SPI_CPOL)
375 		reg |= MX31_CSPICTRL_POL;
376 	if (config->mode & SPI_CS_HIGH)
377 		reg |= MX31_CSPICTRL_SSPOL;
378 	if (cs < 0)
379 		reg |= (cs + 32) <<
380 			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
381 						  MX31_CSPICTRL_CS_SHIFT);
382 
383 	writel(reg, spi_imx->base + MXC_CSPICTRL);
384 
385 	return 0;
386 }
387 
388 static int __maybe_unused mx31_rx_available(struct spi_imx_data *spi_imx)
389 {
390 	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
391 }
392 
393 static void __maybe_unused mx31_reset(struct spi_imx_data *spi_imx)
394 {
395 	/* drain receive buffer */
396 	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
397 		readl(spi_imx->base + MXC_CSPIRXDATA);
398 }
399 
400 #define MX21_INTREG_RR		(1 << 4)
401 #define MX21_INTREG_TEEN	(1 << 9)
402 #define MX21_INTREG_RREN	(1 << 13)
403 
404 #define MX21_CSPICTRL_POL	(1 << 5)
405 #define MX21_CSPICTRL_PHA	(1 << 6)
406 #define MX21_CSPICTRL_SSPOL	(1 << 8)
407 #define MX21_CSPICTRL_XCH	(1 << 9)
408 #define MX21_CSPICTRL_ENABLE	(1 << 10)
409 #define MX21_CSPICTRL_MASTER	(1 << 11)
410 #define MX21_CSPICTRL_DR_SHIFT	14
411 #define MX21_CSPICTRL_CS_SHIFT	19
412 
413 static void __maybe_unused mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
414 {
415 	unsigned int val = 0;
416 
417 	if (enable & MXC_INT_TE)
418 		val |= MX21_INTREG_TEEN;
419 	if (enable & MXC_INT_RR)
420 		val |= MX21_INTREG_RREN;
421 
422 	writel(val, spi_imx->base + MXC_CSPIINT);
423 }
424 
425 static void __maybe_unused mx21_trigger(struct spi_imx_data *spi_imx)
426 {
427 	unsigned int reg;
428 
429 	reg = readl(spi_imx->base + MXC_CSPICTRL);
430 	reg |= MX21_CSPICTRL_XCH;
431 	writel(reg, spi_imx->base + MXC_CSPICTRL);
432 }
433 
434 static int __maybe_unused mx21_config(struct spi_imx_data *spi_imx,
435 		struct spi_imx_config *config)
436 {
437 	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
438 	int cs = spi_imx->chipselect[config->cs];
439 	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
440 
441 	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max) <<
442 		MX21_CSPICTRL_DR_SHIFT;
443 	reg |= config->bpw - 1;
444 
445 	if (config->mode & SPI_CPHA)
446 		reg |= MX21_CSPICTRL_PHA;
447 	if (config->mode & SPI_CPOL)
448 		reg |= MX21_CSPICTRL_POL;
449 	if (config->mode & SPI_CS_HIGH)
450 		reg |= MX21_CSPICTRL_SSPOL;
451 	if (cs < 0)
452 		reg |= (cs + 32) << MX21_CSPICTRL_CS_SHIFT;
453 
454 	writel(reg, spi_imx->base + MXC_CSPICTRL);
455 
456 	return 0;
457 }
458 
459 static int __maybe_unused mx21_rx_available(struct spi_imx_data *spi_imx)
460 {
461 	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
462 }
463 
464 static void __maybe_unused mx21_reset(struct spi_imx_data *spi_imx)
465 {
466 	writel(1, spi_imx->base + MXC_RESET);
467 }
468 
469 #define MX1_INTREG_RR		(1 << 3)
470 #define MX1_INTREG_TEEN		(1 << 8)
471 #define MX1_INTREG_RREN		(1 << 11)
472 
473 #define MX1_CSPICTRL_POL	(1 << 4)
474 #define MX1_CSPICTRL_PHA	(1 << 5)
475 #define MX1_CSPICTRL_XCH	(1 << 8)
476 #define MX1_CSPICTRL_ENABLE	(1 << 9)
477 #define MX1_CSPICTRL_MASTER	(1 << 10)
478 #define MX1_CSPICTRL_DR_SHIFT	13
479 
480 static void __maybe_unused mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
481 {
482 	unsigned int val = 0;
483 
484 	if (enable & MXC_INT_TE)
485 		val |= MX1_INTREG_TEEN;
486 	if (enable & MXC_INT_RR)
487 		val |= MX1_INTREG_RREN;
488 
489 	writel(val, spi_imx->base + MXC_CSPIINT);
490 }
491 
492 static void __maybe_unused mx1_trigger(struct spi_imx_data *spi_imx)
493 {
494 	unsigned int reg;
495 
496 	reg = readl(spi_imx->base + MXC_CSPICTRL);
497 	reg |= MX1_CSPICTRL_XCH;
498 	writel(reg, spi_imx->base + MXC_CSPICTRL);
499 }
500 
501 static int __maybe_unused mx1_config(struct spi_imx_data *spi_imx,
502 		struct spi_imx_config *config)
503 {
504 	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
505 
506 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
507 		MX1_CSPICTRL_DR_SHIFT;
508 	reg |= config->bpw - 1;
509 
510 	if (config->mode & SPI_CPHA)
511 		reg |= MX1_CSPICTRL_PHA;
512 	if (config->mode & SPI_CPOL)
513 		reg |= MX1_CSPICTRL_POL;
514 
515 	writel(reg, spi_imx->base + MXC_CSPICTRL);
516 
517 	return 0;
518 }
519 
520 static int __maybe_unused mx1_rx_available(struct spi_imx_data *spi_imx)
521 {
522 	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
523 }
524 
525 static void __maybe_unused mx1_reset(struct spi_imx_data *spi_imx)
526 {
527 	writel(1, spi_imx->base + MXC_RESET);
528 }
529 
530 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
531 	.intctrl = mx1_intctrl,
532 	.config = mx1_config,
533 	.trigger = mx1_trigger,
534 	.rx_available = mx1_rx_available,
535 	.reset = mx1_reset,
536 	.devtype = IMX1_CSPI,
537 };
538 
539 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
540 	.intctrl = mx21_intctrl,
541 	.config = mx21_config,
542 	.trigger = mx21_trigger,
543 	.rx_available = mx21_rx_available,
544 	.reset = mx21_reset,
545 	.devtype = IMX21_CSPI,
546 };
547 
548 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
549 	/* i.mx27 cspi shares the functions with i.mx21 one */
550 	.intctrl = mx21_intctrl,
551 	.config = mx21_config,
552 	.trigger = mx21_trigger,
553 	.rx_available = mx21_rx_available,
554 	.reset = mx21_reset,
555 	.devtype = IMX27_CSPI,
556 };
557 
558 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
559 	.intctrl = mx31_intctrl,
560 	.config = mx31_config,
561 	.trigger = mx31_trigger,
562 	.rx_available = mx31_rx_available,
563 	.reset = mx31_reset,
564 	.devtype = IMX31_CSPI,
565 };
566 
567 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
568 	/* i.mx35 and later cspi shares the functions with i.mx31 one */
569 	.intctrl = mx31_intctrl,
570 	.config = mx31_config,
571 	.trigger = mx31_trigger,
572 	.rx_available = mx31_rx_available,
573 	.reset = mx31_reset,
574 	.devtype = IMX35_CSPI,
575 };
576 
577 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
578 	.intctrl = mx51_ecspi_intctrl,
579 	.config = mx51_ecspi_config,
580 	.trigger = mx51_ecspi_trigger,
581 	.rx_available = mx51_ecspi_rx_available,
582 	.reset = mx51_ecspi_reset,
583 	.devtype = IMX51_ECSPI,
584 };
585 
586 static struct platform_device_id spi_imx_devtype[] = {
587 	{
588 		.name = "imx1-cspi",
589 		.driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
590 	}, {
591 		.name = "imx21-cspi",
592 		.driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
593 	}, {
594 		.name = "imx27-cspi",
595 		.driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
596 	}, {
597 		.name = "imx31-cspi",
598 		.driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
599 	}, {
600 		.name = "imx35-cspi",
601 		.driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
602 	}, {
603 		.name = "imx51-ecspi",
604 		.driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
605 	}, {
606 		/* sentinel */
607 	}
608 };
609 
610 static const struct of_device_id spi_imx_dt_ids[] = {
611 	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
612 	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
613 	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
614 	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
615 	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
616 	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
617 	{ /* sentinel */ }
618 };
619 
620 static void spi_imx_chipselect(struct spi_device *spi, int is_active)
621 {
622 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
623 	int gpio = spi_imx->chipselect[spi->chip_select];
624 	int active = is_active != BITBANG_CS_INACTIVE;
625 	int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
626 
627 	if (gpio < 0)
628 		return;
629 
630 	gpio_set_value(gpio, dev_is_lowactive ^ active);
631 }
632 
633 static void spi_imx_push(struct spi_imx_data *spi_imx)
634 {
635 	while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) {
636 		if (!spi_imx->count)
637 			break;
638 		spi_imx->tx(spi_imx);
639 		spi_imx->txfifo++;
640 	}
641 
642 	spi_imx->devtype_data->trigger(spi_imx);
643 }
644 
645 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
646 {
647 	struct spi_imx_data *spi_imx = dev_id;
648 
649 	while (spi_imx->devtype_data->rx_available(spi_imx)) {
650 		spi_imx->rx(spi_imx);
651 		spi_imx->txfifo--;
652 	}
653 
654 	if (spi_imx->count) {
655 		spi_imx_push(spi_imx);
656 		return IRQ_HANDLED;
657 	}
658 
659 	if (spi_imx->txfifo) {
660 		/* No data left to push, but still waiting for rx data,
661 		 * enable receive data available interrupt.
662 		 */
663 		spi_imx->devtype_data->intctrl(
664 				spi_imx, MXC_INT_RR);
665 		return IRQ_HANDLED;
666 	}
667 
668 	spi_imx->devtype_data->intctrl(spi_imx, 0);
669 	complete(&spi_imx->xfer_done);
670 
671 	return IRQ_HANDLED;
672 }
673 
674 static int spi_imx_setupxfer(struct spi_device *spi,
675 				 struct spi_transfer *t)
676 {
677 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
678 	struct spi_imx_config config;
679 
680 	config.bpw = t ? t->bits_per_word : spi->bits_per_word;
681 	config.speed_hz  = t ? t->speed_hz : spi->max_speed_hz;
682 	config.mode = spi->mode;
683 	config.cs = spi->chip_select;
684 
685 	if (!config.speed_hz)
686 		config.speed_hz = spi->max_speed_hz;
687 	if (!config.bpw)
688 		config.bpw = spi->bits_per_word;
689 	if (!config.speed_hz)
690 		config.speed_hz = spi->max_speed_hz;
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 >= 0)
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 	int i, ret, num_cs;
762 
763 	if (!np && !mxc_platform_info) {
764 		dev_err(&pdev->dev, "can't get the platform data\n");
765 		return -EINVAL;
766 	}
767 
768 	ret = of_property_read_u32(np, "fsl,spi-num-chipselects", &num_cs);
769 	if (ret < 0)
770 		num_cs = mxc_platform_info->num_chipselect;
771 
772 	master = spi_alloc_master(&pdev->dev,
773 			sizeof(struct spi_imx_data) + sizeof(int) * num_cs);
774 	if (!master)
775 		return -ENOMEM;
776 
777 	platform_set_drvdata(pdev, master);
778 
779 	master->bus_num = pdev->id;
780 	master->num_chipselect = num_cs;
781 
782 	spi_imx = spi_master_get_devdata(master);
783 	spi_imx->bitbang.master = spi_master_get(master);
784 
785 	for (i = 0; i < master->num_chipselect; i++) {
786 		int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
787 		if (cs_gpio < 0)
788 			cs_gpio = mxc_platform_info->chipselect[i];
789 
790 		spi_imx->chipselect[i] = cs_gpio;
791 		if (cs_gpio < 0)
792 			continue;
793 
794 		ret = gpio_request(spi_imx->chipselect[i], DRIVER_NAME);
795 		if (ret) {
796 			while (i > 0) {
797 				i--;
798 				if (spi_imx->chipselect[i] >= 0)
799 					gpio_free(spi_imx->chipselect[i]);
800 			}
801 			dev_err(&pdev->dev, "can't get cs gpios\n");
802 			goto out_master_put;
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 	spi_imx->clk = clk_get(&pdev->dev, NULL);
850 	if (IS_ERR(spi_imx->clk)) {
851 		dev_err(&pdev->dev, "unable to get clock\n");
852 		ret = PTR_ERR(spi_imx->clk);
853 		goto out_free_irq;
854 	}
855 
856 	clk_enable(spi_imx->clk);
857 	spi_imx->spi_clk = clk_get_rate(spi_imx->clk);
858 
859 	spi_imx->devtype_data->reset(spi_imx);
860 
861 	spi_imx->devtype_data->intctrl(spi_imx, 0);
862 
863 	master->dev.of_node = pdev->dev.of_node;
864 	ret = spi_bitbang_start(&spi_imx->bitbang);
865 	if (ret) {
866 		dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
867 		goto out_clk_put;
868 	}
869 
870 	dev_info(&pdev->dev, "probed\n");
871 
872 	return ret;
873 
874 out_clk_put:
875 	clk_disable(spi_imx->clk);
876 	clk_put(spi_imx->clk);
877 out_free_irq:
878 	free_irq(spi_imx->irq, spi_imx);
879 out_iounmap:
880 	iounmap(spi_imx->base);
881 out_release_mem:
882 	release_mem_region(res->start, resource_size(res));
883 out_gpio_free:
884 	for (i = 0; i < master->num_chipselect; i++)
885 		if (spi_imx->chipselect[i] >= 0)
886 			gpio_free(spi_imx->chipselect[i]);
887 out_master_put:
888 	spi_master_put(master);
889 	kfree(master);
890 	platform_set_drvdata(pdev, NULL);
891 	return ret;
892 }
893 
894 static int __devexit spi_imx_remove(struct platform_device *pdev)
895 {
896 	struct spi_master *master = platform_get_drvdata(pdev);
897 	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
898 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
899 	int i;
900 
901 	spi_bitbang_stop(&spi_imx->bitbang);
902 
903 	writel(0, spi_imx->base + MXC_CSPICTRL);
904 	clk_disable(spi_imx->clk);
905 	clk_put(spi_imx->clk);
906 	free_irq(spi_imx->irq, spi_imx);
907 	iounmap(spi_imx->base);
908 
909 	for (i = 0; i < master->num_chipselect; i++)
910 		if (spi_imx->chipselect[i] >= 0)
911 			gpio_free(spi_imx->chipselect[i]);
912 
913 	spi_master_put(master);
914 
915 	release_mem_region(res->start, resource_size(res));
916 
917 	platform_set_drvdata(pdev, NULL);
918 
919 	return 0;
920 }
921 
922 static struct platform_driver spi_imx_driver = {
923 	.driver = {
924 		   .name = DRIVER_NAME,
925 		   .owner = THIS_MODULE,
926 		   .of_match_table = spi_imx_dt_ids,
927 		   },
928 	.id_table = spi_imx_devtype,
929 	.probe = spi_imx_probe,
930 	.remove = __devexit_p(spi_imx_remove),
931 };
932 module_platform_driver(spi_imx_driver);
933 
934 MODULE_DESCRIPTION("SPI Master Controller driver");
935 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
936 MODULE_LICENSE("GPL");
937