xref: /openbmc/linux/drivers/spi/spi-imx.c (revision 5303b8d3)
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/dmaengine.h>
25 #include <linux/dma-mapping.h>
26 #include <linux/err.h>
27 #include <linux/gpio.h>
28 #include <linux/interrupt.h>
29 #include <linux/io.h>
30 #include <linux/irq.h>
31 #include <linux/kernel.h>
32 #include <linux/module.h>
33 #include <linux/platform_device.h>
34 #include <linux/slab.h>
35 #include <linux/spi/spi.h>
36 #include <linux/spi/spi_bitbang.h>
37 #include <linux/types.h>
38 #include <linux/of.h>
39 #include <linux/of_device.h>
40 #include <linux/of_gpio.h>
41 
42 #include <linux/platform_data/dma-imx.h>
43 #include <linux/platform_data/spi-imx.h>
44 
45 #define DRIVER_NAME "spi_imx"
46 
47 #define MXC_CSPIRXDATA		0x00
48 #define MXC_CSPITXDATA		0x04
49 #define MXC_CSPICTRL		0x08
50 #define MXC_CSPIINT		0x0c
51 #define MXC_RESET		0x1c
52 
53 /* generic defines to abstract from the different register layouts */
54 #define MXC_INT_RR	(1 << 0) /* Receive data ready interrupt */
55 #define MXC_INT_TE	(1 << 1) /* Transmit FIFO empty interrupt */
56 
57 /* The maximum  bytes that a sdma BD can transfer.*/
58 #define MAX_SDMA_BD_BYTES  (1 << 15)
59 
60 enum spi_imx_devtype {
61 	IMX1_CSPI,
62 	IMX21_CSPI,
63 	IMX27_CSPI,
64 	IMX31_CSPI,
65 	IMX35_CSPI,	/* CSPI on all i.mx except above */
66 	IMX51_ECSPI,	/* ECSPI on i.mx51 and later */
67 };
68 
69 struct spi_imx_data;
70 
71 struct spi_imx_devtype_data {
72 	void (*intctrl)(struct spi_imx_data *, int);
73 	int (*config)(struct spi_device *);
74 	void (*trigger)(struct spi_imx_data *);
75 	int (*rx_available)(struct spi_imx_data *);
76 	void (*reset)(struct spi_imx_data *);
77 	enum spi_imx_devtype devtype;
78 };
79 
80 struct spi_imx_data {
81 	struct spi_bitbang bitbang;
82 	struct device *dev;
83 
84 	struct completion xfer_done;
85 	void __iomem *base;
86 	unsigned long base_phys;
87 
88 	struct clk *clk_per;
89 	struct clk *clk_ipg;
90 	unsigned long spi_clk;
91 	unsigned int spi_bus_clk;
92 
93 	unsigned int speed_hz;
94 	unsigned int bits_per_word;
95 	unsigned int spi_drctl;
96 
97 	unsigned int count;
98 	void (*tx)(struct spi_imx_data *);
99 	void (*rx)(struct spi_imx_data *);
100 	void *rx_buf;
101 	const void *tx_buf;
102 	unsigned int txfifo; /* number of words pushed in tx FIFO */
103 
104 	/* DMA */
105 	bool usedma;
106 	u32 wml;
107 	struct completion dma_rx_completion;
108 	struct completion dma_tx_completion;
109 
110 	const struct spi_imx_devtype_data *devtype_data;
111 };
112 
113 static inline int is_imx27_cspi(struct spi_imx_data *d)
114 {
115 	return d->devtype_data->devtype == IMX27_CSPI;
116 }
117 
118 static inline int is_imx35_cspi(struct spi_imx_data *d)
119 {
120 	return d->devtype_data->devtype == IMX35_CSPI;
121 }
122 
123 static inline int is_imx51_ecspi(struct spi_imx_data *d)
124 {
125 	return d->devtype_data->devtype == IMX51_ECSPI;
126 }
127 
128 static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d)
129 {
130 	return is_imx51_ecspi(d) ? 64 : 8;
131 }
132 
133 #define MXC_SPI_BUF_RX(type)						\
134 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx)		\
135 {									\
136 	unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);	\
137 									\
138 	if (spi_imx->rx_buf) {						\
139 		*(type *)spi_imx->rx_buf = val;				\
140 		spi_imx->rx_buf += sizeof(type);			\
141 	}								\
142 }
143 
144 #define MXC_SPI_BUF_TX(type)						\
145 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx)		\
146 {									\
147 	type val = 0;							\
148 									\
149 	if (spi_imx->tx_buf) {						\
150 		val = *(type *)spi_imx->tx_buf;				\
151 		spi_imx->tx_buf += sizeof(type);			\
152 	}								\
153 									\
154 	spi_imx->count -= sizeof(type);					\
155 									\
156 	writel(val, spi_imx->base + MXC_CSPITXDATA);			\
157 }
158 
159 MXC_SPI_BUF_RX(u8)
160 MXC_SPI_BUF_TX(u8)
161 MXC_SPI_BUF_RX(u16)
162 MXC_SPI_BUF_TX(u16)
163 MXC_SPI_BUF_RX(u32)
164 MXC_SPI_BUF_TX(u32)
165 
166 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
167  * (which is currently not the case in this driver)
168  */
169 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
170 	256, 384, 512, 768, 1024};
171 
172 /* MX21, MX27 */
173 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
174 		unsigned int fspi, unsigned int max, unsigned int *fres)
175 {
176 	int i;
177 
178 	for (i = 2; i < max; i++)
179 		if (fspi * mxc_clkdivs[i] >= fin)
180 			break;
181 
182 	*fres = fin / mxc_clkdivs[i];
183 	return i;
184 }
185 
186 /* MX1, MX31, MX35, MX51 CSPI */
187 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
188 		unsigned int fspi, unsigned int *fres)
189 {
190 	int i, div = 4;
191 
192 	for (i = 0; i < 7; i++) {
193 		if (fspi * div >= fin)
194 			goto out;
195 		div <<= 1;
196 	}
197 
198 out:
199 	*fres = fin / div;
200 	return i;
201 }
202 
203 static int spi_imx_bytes_per_word(const int bits_per_word)
204 {
205 	return DIV_ROUND_UP(bits_per_word, BITS_PER_BYTE);
206 }
207 
208 static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
209 			 struct spi_transfer *transfer)
210 {
211 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
212 	unsigned int bytes_per_word, i;
213 
214 	if (!master->dma_rx)
215 		return false;
216 
217 	bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
218 
219 	if (bytes_per_word != 1 && bytes_per_word != 2 && bytes_per_word != 4)
220 		return false;
221 
222 	for (i = spi_imx_get_fifosize(spi_imx) / 2; i > 0; i--) {
223 		if (!(transfer->len % (i * bytes_per_word)))
224 			break;
225 	}
226 
227 	if (i == 0)
228 		return false;
229 
230 	spi_imx->wml = i;
231 
232 	return true;
233 }
234 
235 #define MX51_ECSPI_CTRL		0x08
236 #define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
237 #define MX51_ECSPI_CTRL_XCH		(1 <<  2)
238 #define MX51_ECSPI_CTRL_SMC		(1 << 3)
239 #define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
240 #define MX51_ECSPI_CTRL_DRCTL(drctl)	((drctl) << 16)
241 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
242 #define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
243 #define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
244 #define MX51_ECSPI_CTRL_BL_OFFSET	20
245 
246 #define MX51_ECSPI_CONFIG	0x0c
247 #define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
248 #define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
249 #define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
250 #define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
251 #define MX51_ECSPI_CONFIG_SCLKCTL(cs)	(1 << ((cs) + 20))
252 
253 #define MX51_ECSPI_INT		0x10
254 #define MX51_ECSPI_INT_TEEN		(1 <<  0)
255 #define MX51_ECSPI_INT_RREN		(1 <<  3)
256 
257 #define MX51_ECSPI_DMA      0x14
258 #define MX51_ECSPI_DMA_TX_WML(wml)	((wml) & 0x3f)
259 #define MX51_ECSPI_DMA_RX_WML(wml)	(((wml) & 0x3f) << 16)
260 #define MX51_ECSPI_DMA_RXT_WML(wml)	(((wml) & 0x3f) << 24)
261 
262 #define MX51_ECSPI_DMA_TEDEN		(1 << 7)
263 #define MX51_ECSPI_DMA_RXDEN		(1 << 23)
264 #define MX51_ECSPI_DMA_RXTDEN		(1 << 31)
265 
266 #define MX51_ECSPI_STAT		0x18
267 #define MX51_ECSPI_STAT_RR		(1 <<  3)
268 
269 #define MX51_ECSPI_TESTREG	0x20
270 #define MX51_ECSPI_TESTREG_LBC	BIT(31)
271 
272 /* MX51 eCSPI */
273 static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
274 				      unsigned int fspi, unsigned int *fres)
275 {
276 	/*
277 	 * there are two 4-bit dividers, the pre-divider divides by
278 	 * $pre, the post-divider by 2^$post
279 	 */
280 	unsigned int pre, post;
281 	unsigned int fin = spi_imx->spi_clk;
282 
283 	if (unlikely(fspi > fin))
284 		return 0;
285 
286 	post = fls(fin) - fls(fspi);
287 	if (fin > fspi << post)
288 		post++;
289 
290 	/* now we have: (fin <= fspi << post) with post being minimal */
291 
292 	post = max(4U, post) - 4;
293 	if (unlikely(post > 0xf)) {
294 		dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
295 				fspi, fin);
296 		return 0xff;
297 	}
298 
299 	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
300 
301 	dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
302 			__func__, fin, fspi, post, pre);
303 
304 	/* Resulting frequency for the SCLK line. */
305 	*fres = (fin / (pre + 1)) >> post;
306 
307 	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
308 		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
309 }
310 
311 static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
312 {
313 	unsigned val = 0;
314 
315 	if (enable & MXC_INT_TE)
316 		val |= MX51_ECSPI_INT_TEEN;
317 
318 	if (enable & MXC_INT_RR)
319 		val |= MX51_ECSPI_INT_RREN;
320 
321 	writel(val, spi_imx->base + MX51_ECSPI_INT);
322 }
323 
324 static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
325 {
326 	u32 reg;
327 
328 	reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
329 	reg |= MX51_ECSPI_CTRL_XCH;
330 	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
331 }
332 
333 static int mx51_ecspi_config(struct spi_device *spi)
334 {
335 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
336 	u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
337 	u32 clk = spi_imx->speed_hz, delay, reg;
338 	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
339 
340 	/*
341 	 * The hardware seems to have a race condition when changing modes. The
342 	 * current assumption is that the selection of the channel arrives
343 	 * earlier in the hardware than the mode bits when they are written at
344 	 * the same time.
345 	 * So set master mode for all channels as we do not support slave mode.
346 	 */
347 	ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
348 
349 	/*
350 	 * Enable SPI_RDY handling (falling edge/level triggered).
351 	 */
352 	if (spi->mode & SPI_READY)
353 		ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
354 
355 	/* set clock speed */
356 	ctrl |= mx51_ecspi_clkdiv(spi_imx, spi_imx->speed_hz, &clk);
357 	spi_imx->spi_bus_clk = clk;
358 
359 	/* set chip select to use */
360 	ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
361 
362 	ctrl |= (spi_imx->bits_per_word - 1) << MX51_ECSPI_CTRL_BL_OFFSET;
363 
364 	cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
365 
366 	if (spi->mode & SPI_CPHA)
367 		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
368 	else
369 		cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
370 
371 	if (spi->mode & SPI_CPOL) {
372 		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
373 		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
374 	} else {
375 		cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
376 		cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
377 	}
378 	if (spi->mode & SPI_CS_HIGH)
379 		cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
380 	else
381 		cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
382 
383 	if (spi_imx->usedma)
384 		ctrl |= MX51_ECSPI_CTRL_SMC;
385 
386 	/* CTRL register always go first to bring out controller from reset */
387 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
388 
389 	reg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
390 	if (spi->mode & SPI_LOOP)
391 		reg |= MX51_ECSPI_TESTREG_LBC;
392 	else
393 		reg &= ~MX51_ECSPI_TESTREG_LBC;
394 	writel(reg, spi_imx->base + MX51_ECSPI_TESTREG);
395 
396 	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
397 
398 	/*
399 	 * Wait until the changes in the configuration register CONFIGREG
400 	 * propagate into the hardware. It takes exactly one tick of the
401 	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
402 	 * effect of the delay it takes for the hardware to apply changes
403 	 * is noticable if the SCLK clock run very slow. In such a case, if
404 	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
405 	 * be asserted before the SCLK polarity changes, which would disrupt
406 	 * the SPI communication as the device on the other end would consider
407 	 * the change of SCLK polarity as a clock tick already.
408 	 */
409 	delay = (2 * 1000000) / clk;
410 	if (likely(delay < 10))	/* SCLK is faster than 100 kHz */
411 		udelay(delay);
412 	else			/* SCLK is _very_ slow */
413 		usleep_range(delay, delay + 10);
414 
415 	/*
416 	 * Configure the DMA register: setup the watermark
417 	 * and enable DMA request.
418 	 */
419 
420 	writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml) |
421 		MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
422 		MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
423 		MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
424 		MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
425 
426 	return 0;
427 }
428 
429 static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
430 {
431 	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
432 }
433 
434 static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
435 {
436 	/* drain receive buffer */
437 	while (mx51_ecspi_rx_available(spi_imx))
438 		readl(spi_imx->base + MXC_CSPIRXDATA);
439 }
440 
441 #define MX31_INTREG_TEEN	(1 << 0)
442 #define MX31_INTREG_RREN	(1 << 3)
443 
444 #define MX31_CSPICTRL_ENABLE	(1 << 0)
445 #define MX31_CSPICTRL_MASTER	(1 << 1)
446 #define MX31_CSPICTRL_XCH	(1 << 2)
447 #define MX31_CSPICTRL_SMC	(1 << 3)
448 #define MX31_CSPICTRL_POL	(1 << 4)
449 #define MX31_CSPICTRL_PHA	(1 << 5)
450 #define MX31_CSPICTRL_SSCTL	(1 << 6)
451 #define MX31_CSPICTRL_SSPOL	(1 << 7)
452 #define MX31_CSPICTRL_BC_SHIFT	8
453 #define MX35_CSPICTRL_BL_SHIFT	20
454 #define MX31_CSPICTRL_CS_SHIFT	24
455 #define MX35_CSPICTRL_CS_SHIFT	12
456 #define MX31_CSPICTRL_DR_SHIFT	16
457 
458 #define MX31_CSPI_DMAREG	0x10
459 #define MX31_DMAREG_RH_DEN	(1<<4)
460 #define MX31_DMAREG_TH_DEN	(1<<1)
461 
462 #define MX31_CSPISTATUS		0x14
463 #define MX31_STATUS_RR		(1 << 3)
464 
465 #define MX31_CSPI_TESTREG	0x1C
466 #define MX31_TEST_LBC		(1 << 14)
467 
468 /* These functions also work for the i.MX35, but be aware that
469  * the i.MX35 has a slightly different register layout for bits
470  * we do not use here.
471  */
472 static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
473 {
474 	unsigned int val = 0;
475 
476 	if (enable & MXC_INT_TE)
477 		val |= MX31_INTREG_TEEN;
478 	if (enable & MXC_INT_RR)
479 		val |= MX31_INTREG_RREN;
480 
481 	writel(val, spi_imx->base + MXC_CSPIINT);
482 }
483 
484 static void mx31_trigger(struct spi_imx_data *spi_imx)
485 {
486 	unsigned int reg;
487 
488 	reg = readl(spi_imx->base + MXC_CSPICTRL);
489 	reg |= MX31_CSPICTRL_XCH;
490 	writel(reg, spi_imx->base + MXC_CSPICTRL);
491 }
492 
493 static int mx31_config(struct spi_device *spi)
494 {
495 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
496 	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
497 	unsigned int clk;
498 
499 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->speed_hz, &clk) <<
500 		MX31_CSPICTRL_DR_SHIFT;
501 	spi_imx->spi_bus_clk = clk;
502 
503 	if (is_imx35_cspi(spi_imx)) {
504 		reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
505 		reg |= MX31_CSPICTRL_SSCTL;
506 	} else {
507 		reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
508 	}
509 
510 	if (spi->mode & SPI_CPHA)
511 		reg |= MX31_CSPICTRL_PHA;
512 	if (spi->mode & SPI_CPOL)
513 		reg |= MX31_CSPICTRL_POL;
514 	if (spi->mode & SPI_CS_HIGH)
515 		reg |= MX31_CSPICTRL_SSPOL;
516 	if (spi->cs_gpio < 0)
517 		reg |= (spi->cs_gpio + 32) <<
518 			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
519 						  MX31_CSPICTRL_CS_SHIFT);
520 
521 	if (spi_imx->usedma)
522 		reg |= MX31_CSPICTRL_SMC;
523 
524 	writel(reg, spi_imx->base + MXC_CSPICTRL);
525 
526 	reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
527 	if (spi->mode & SPI_LOOP)
528 		reg |= MX31_TEST_LBC;
529 	else
530 		reg &= ~MX31_TEST_LBC;
531 	writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
532 
533 	if (spi_imx->usedma) {
534 		/* configure DMA requests when RXFIFO is half full and
535 		   when TXFIFO is half empty */
536 		writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
537 			spi_imx->base + MX31_CSPI_DMAREG);
538 	}
539 
540 	return 0;
541 }
542 
543 static int mx31_rx_available(struct spi_imx_data *spi_imx)
544 {
545 	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
546 }
547 
548 static void mx31_reset(struct spi_imx_data *spi_imx)
549 {
550 	/* drain receive buffer */
551 	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
552 		readl(spi_imx->base + MXC_CSPIRXDATA);
553 }
554 
555 #define MX21_INTREG_RR		(1 << 4)
556 #define MX21_INTREG_TEEN	(1 << 9)
557 #define MX21_INTREG_RREN	(1 << 13)
558 
559 #define MX21_CSPICTRL_POL	(1 << 5)
560 #define MX21_CSPICTRL_PHA	(1 << 6)
561 #define MX21_CSPICTRL_SSPOL	(1 << 8)
562 #define MX21_CSPICTRL_XCH	(1 << 9)
563 #define MX21_CSPICTRL_ENABLE	(1 << 10)
564 #define MX21_CSPICTRL_MASTER	(1 << 11)
565 #define MX21_CSPICTRL_DR_SHIFT	14
566 #define MX21_CSPICTRL_CS_SHIFT	19
567 
568 static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
569 {
570 	unsigned int val = 0;
571 
572 	if (enable & MXC_INT_TE)
573 		val |= MX21_INTREG_TEEN;
574 	if (enable & MXC_INT_RR)
575 		val |= MX21_INTREG_RREN;
576 
577 	writel(val, spi_imx->base + MXC_CSPIINT);
578 }
579 
580 static void mx21_trigger(struct spi_imx_data *spi_imx)
581 {
582 	unsigned int reg;
583 
584 	reg = readl(spi_imx->base + MXC_CSPICTRL);
585 	reg |= MX21_CSPICTRL_XCH;
586 	writel(reg, spi_imx->base + MXC_CSPICTRL);
587 }
588 
589 static int mx21_config(struct spi_device *spi)
590 {
591 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
592 	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
593 	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
594 	unsigned int clk;
595 
596 	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, spi_imx->speed_hz, max, &clk)
597 		<< MX21_CSPICTRL_DR_SHIFT;
598 	spi_imx->spi_bus_clk = clk;
599 
600 	reg |= spi_imx->bits_per_word - 1;
601 
602 	if (spi->mode & SPI_CPHA)
603 		reg |= MX21_CSPICTRL_PHA;
604 	if (spi->mode & SPI_CPOL)
605 		reg |= MX21_CSPICTRL_POL;
606 	if (spi->mode & SPI_CS_HIGH)
607 		reg |= MX21_CSPICTRL_SSPOL;
608 	if (spi->cs_gpio < 0)
609 		reg |= (spi->cs_gpio + 32) << MX21_CSPICTRL_CS_SHIFT;
610 
611 	writel(reg, spi_imx->base + MXC_CSPICTRL);
612 
613 	return 0;
614 }
615 
616 static int mx21_rx_available(struct spi_imx_data *spi_imx)
617 {
618 	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
619 }
620 
621 static void mx21_reset(struct spi_imx_data *spi_imx)
622 {
623 	writel(1, spi_imx->base + MXC_RESET);
624 }
625 
626 #define MX1_INTREG_RR		(1 << 3)
627 #define MX1_INTREG_TEEN		(1 << 8)
628 #define MX1_INTREG_RREN		(1 << 11)
629 
630 #define MX1_CSPICTRL_POL	(1 << 4)
631 #define MX1_CSPICTRL_PHA	(1 << 5)
632 #define MX1_CSPICTRL_XCH	(1 << 8)
633 #define MX1_CSPICTRL_ENABLE	(1 << 9)
634 #define MX1_CSPICTRL_MASTER	(1 << 10)
635 #define MX1_CSPICTRL_DR_SHIFT	13
636 
637 static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
638 {
639 	unsigned int val = 0;
640 
641 	if (enable & MXC_INT_TE)
642 		val |= MX1_INTREG_TEEN;
643 	if (enable & MXC_INT_RR)
644 		val |= MX1_INTREG_RREN;
645 
646 	writel(val, spi_imx->base + MXC_CSPIINT);
647 }
648 
649 static void mx1_trigger(struct spi_imx_data *spi_imx)
650 {
651 	unsigned int reg;
652 
653 	reg = readl(spi_imx->base + MXC_CSPICTRL);
654 	reg |= MX1_CSPICTRL_XCH;
655 	writel(reg, spi_imx->base + MXC_CSPICTRL);
656 }
657 
658 static int mx1_config(struct spi_device *spi)
659 {
660 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
661 	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
662 	unsigned int clk;
663 
664 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->speed_hz, &clk) <<
665 		MX1_CSPICTRL_DR_SHIFT;
666 	spi_imx->spi_bus_clk = clk;
667 
668 	reg |= spi_imx->bits_per_word - 1;
669 
670 	if (spi->mode & SPI_CPHA)
671 		reg |= MX1_CSPICTRL_PHA;
672 	if (spi->mode & SPI_CPOL)
673 		reg |= MX1_CSPICTRL_POL;
674 
675 	writel(reg, spi_imx->base + MXC_CSPICTRL);
676 
677 	return 0;
678 }
679 
680 static int mx1_rx_available(struct spi_imx_data *spi_imx)
681 {
682 	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
683 }
684 
685 static void mx1_reset(struct spi_imx_data *spi_imx)
686 {
687 	writel(1, spi_imx->base + MXC_RESET);
688 }
689 
690 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
691 	.intctrl = mx1_intctrl,
692 	.config = mx1_config,
693 	.trigger = mx1_trigger,
694 	.rx_available = mx1_rx_available,
695 	.reset = mx1_reset,
696 	.devtype = IMX1_CSPI,
697 };
698 
699 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
700 	.intctrl = mx21_intctrl,
701 	.config = mx21_config,
702 	.trigger = mx21_trigger,
703 	.rx_available = mx21_rx_available,
704 	.reset = mx21_reset,
705 	.devtype = IMX21_CSPI,
706 };
707 
708 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
709 	/* i.mx27 cspi shares the functions with i.mx21 one */
710 	.intctrl = mx21_intctrl,
711 	.config = mx21_config,
712 	.trigger = mx21_trigger,
713 	.rx_available = mx21_rx_available,
714 	.reset = mx21_reset,
715 	.devtype = IMX27_CSPI,
716 };
717 
718 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
719 	.intctrl = mx31_intctrl,
720 	.config = mx31_config,
721 	.trigger = mx31_trigger,
722 	.rx_available = mx31_rx_available,
723 	.reset = mx31_reset,
724 	.devtype = IMX31_CSPI,
725 };
726 
727 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
728 	/* i.mx35 and later cspi shares the functions with i.mx31 one */
729 	.intctrl = mx31_intctrl,
730 	.config = mx31_config,
731 	.trigger = mx31_trigger,
732 	.rx_available = mx31_rx_available,
733 	.reset = mx31_reset,
734 	.devtype = IMX35_CSPI,
735 };
736 
737 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
738 	.intctrl = mx51_ecspi_intctrl,
739 	.config = mx51_ecspi_config,
740 	.trigger = mx51_ecspi_trigger,
741 	.rx_available = mx51_ecspi_rx_available,
742 	.reset = mx51_ecspi_reset,
743 	.devtype = IMX51_ECSPI,
744 };
745 
746 static const struct platform_device_id spi_imx_devtype[] = {
747 	{
748 		.name = "imx1-cspi",
749 		.driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
750 	}, {
751 		.name = "imx21-cspi",
752 		.driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
753 	}, {
754 		.name = "imx27-cspi",
755 		.driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
756 	}, {
757 		.name = "imx31-cspi",
758 		.driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
759 	}, {
760 		.name = "imx35-cspi",
761 		.driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
762 	}, {
763 		.name = "imx51-ecspi",
764 		.driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
765 	}, {
766 		/* sentinel */
767 	}
768 };
769 
770 static const struct of_device_id spi_imx_dt_ids[] = {
771 	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
772 	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
773 	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
774 	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
775 	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
776 	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
777 	{ /* sentinel */ }
778 };
779 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
780 
781 static void spi_imx_chipselect(struct spi_device *spi, int is_active)
782 {
783 	int active = is_active != BITBANG_CS_INACTIVE;
784 	int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
785 
786 	if (!gpio_is_valid(spi->cs_gpio))
787 		return;
788 
789 	gpio_set_value(spi->cs_gpio, dev_is_lowactive ^ active);
790 }
791 
792 static void spi_imx_push(struct spi_imx_data *spi_imx)
793 {
794 	while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) {
795 		if (!spi_imx->count)
796 			break;
797 		spi_imx->tx(spi_imx);
798 		spi_imx->txfifo++;
799 	}
800 
801 	spi_imx->devtype_data->trigger(spi_imx);
802 }
803 
804 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
805 {
806 	struct spi_imx_data *spi_imx = dev_id;
807 
808 	while (spi_imx->devtype_data->rx_available(spi_imx)) {
809 		spi_imx->rx(spi_imx);
810 		spi_imx->txfifo--;
811 	}
812 
813 	if (spi_imx->count) {
814 		spi_imx_push(spi_imx);
815 		return IRQ_HANDLED;
816 	}
817 
818 	if (spi_imx->txfifo) {
819 		/* No data left to push, but still waiting for rx data,
820 		 * enable receive data available interrupt.
821 		 */
822 		spi_imx->devtype_data->intctrl(
823 				spi_imx, MXC_INT_RR);
824 		return IRQ_HANDLED;
825 	}
826 
827 	spi_imx->devtype_data->intctrl(spi_imx, 0);
828 	complete(&spi_imx->xfer_done);
829 
830 	return IRQ_HANDLED;
831 }
832 
833 static int spi_imx_dma_configure(struct spi_master *master)
834 {
835 	int ret;
836 	enum dma_slave_buswidth buswidth;
837 	struct dma_slave_config rx = {}, tx = {};
838 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
839 
840 	switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
841 	case 4:
842 		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
843 		break;
844 	case 2:
845 		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
846 		break;
847 	case 1:
848 		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
849 		break;
850 	default:
851 		return -EINVAL;
852 	}
853 
854 	tx.direction = DMA_MEM_TO_DEV;
855 	tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
856 	tx.dst_addr_width = buswidth;
857 	tx.dst_maxburst = spi_imx->wml;
858 	ret = dmaengine_slave_config(master->dma_tx, &tx);
859 	if (ret) {
860 		dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
861 		return ret;
862 	}
863 
864 	rx.direction = DMA_DEV_TO_MEM;
865 	rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
866 	rx.src_addr_width = buswidth;
867 	rx.src_maxburst = spi_imx->wml;
868 	ret = dmaengine_slave_config(master->dma_rx, &rx);
869 	if (ret) {
870 		dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
871 		return ret;
872 	}
873 
874 	return 0;
875 }
876 
877 static int spi_imx_setupxfer(struct spi_device *spi,
878 				 struct spi_transfer *t)
879 {
880 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
881 	int ret;
882 
883 	if (!t)
884 		return 0;
885 
886 	spi_imx->bits_per_word = t->bits_per_word;
887 	spi_imx->speed_hz  = t->speed_hz;
888 
889 	/* Initialize the functions for transfer */
890 	if (spi_imx->bits_per_word <= 8) {
891 		spi_imx->rx = spi_imx_buf_rx_u8;
892 		spi_imx->tx = spi_imx_buf_tx_u8;
893 	} else if (spi_imx->bits_per_word <= 16) {
894 		spi_imx->rx = spi_imx_buf_rx_u16;
895 		spi_imx->tx = spi_imx_buf_tx_u16;
896 	} else {
897 		spi_imx->rx = spi_imx_buf_rx_u32;
898 		spi_imx->tx = spi_imx_buf_tx_u32;
899 	}
900 
901 	if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
902 		spi_imx->usedma = 1;
903 	else
904 		spi_imx->usedma = 0;
905 
906 	if (spi_imx->usedma) {
907 		ret = spi_imx_dma_configure(spi->master);
908 		if (ret)
909 			return ret;
910 	}
911 
912 	spi_imx->devtype_data->config(spi);
913 
914 	return 0;
915 }
916 
917 static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
918 {
919 	struct spi_master *master = spi_imx->bitbang.master;
920 
921 	if (master->dma_rx) {
922 		dma_release_channel(master->dma_rx);
923 		master->dma_rx = NULL;
924 	}
925 
926 	if (master->dma_tx) {
927 		dma_release_channel(master->dma_tx);
928 		master->dma_tx = NULL;
929 	}
930 }
931 
932 static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
933 			     struct spi_master *master)
934 {
935 	int ret;
936 
937 	/* use pio mode for i.mx6dl chip TKT238285 */
938 	if (of_machine_is_compatible("fsl,imx6dl"))
939 		return 0;
940 
941 	spi_imx->wml = spi_imx_get_fifosize(spi_imx) / 2;
942 
943 	/* Prepare for TX DMA: */
944 	master->dma_tx = dma_request_slave_channel_reason(dev, "tx");
945 	if (IS_ERR(master->dma_tx)) {
946 		ret = PTR_ERR(master->dma_tx);
947 		dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
948 		master->dma_tx = NULL;
949 		goto err;
950 	}
951 
952 	/* Prepare for RX : */
953 	master->dma_rx = dma_request_slave_channel_reason(dev, "rx");
954 	if (IS_ERR(master->dma_rx)) {
955 		ret = PTR_ERR(master->dma_rx);
956 		dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
957 		master->dma_rx = NULL;
958 		goto err;
959 	}
960 
961 	init_completion(&spi_imx->dma_rx_completion);
962 	init_completion(&spi_imx->dma_tx_completion);
963 	master->can_dma = spi_imx_can_dma;
964 	master->max_dma_len = MAX_SDMA_BD_BYTES;
965 	spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
966 					 SPI_MASTER_MUST_TX;
967 
968 	return 0;
969 err:
970 	spi_imx_sdma_exit(spi_imx);
971 	return ret;
972 }
973 
974 static void spi_imx_dma_rx_callback(void *cookie)
975 {
976 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
977 
978 	complete(&spi_imx->dma_rx_completion);
979 }
980 
981 static void spi_imx_dma_tx_callback(void *cookie)
982 {
983 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
984 
985 	complete(&spi_imx->dma_tx_completion);
986 }
987 
988 static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
989 {
990 	unsigned long timeout = 0;
991 
992 	/* Time with actual data transfer and CS change delay related to HW */
993 	timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
994 
995 	/* Add extra second for scheduler related activities */
996 	timeout += 1;
997 
998 	/* Double calculated timeout */
999 	return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1000 }
1001 
1002 static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1003 				struct spi_transfer *transfer)
1004 {
1005 	struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1006 	unsigned long transfer_timeout;
1007 	unsigned long timeout;
1008 	struct spi_master *master = spi_imx->bitbang.master;
1009 	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1010 
1011 	/*
1012 	 * The TX DMA setup starts the transfer, so make sure RX is configured
1013 	 * before TX.
1014 	 */
1015 	desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
1016 				rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1017 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1018 	if (!desc_rx)
1019 		return -EINVAL;
1020 
1021 	desc_rx->callback = spi_imx_dma_rx_callback;
1022 	desc_rx->callback_param = (void *)spi_imx;
1023 	dmaengine_submit(desc_rx);
1024 	reinit_completion(&spi_imx->dma_rx_completion);
1025 	dma_async_issue_pending(master->dma_rx);
1026 
1027 	desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
1028 				tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1029 				DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1030 	if (!desc_tx) {
1031 		dmaengine_terminate_all(master->dma_tx);
1032 		return -EINVAL;
1033 	}
1034 
1035 	desc_tx->callback = spi_imx_dma_tx_callback;
1036 	desc_tx->callback_param = (void *)spi_imx;
1037 	dmaengine_submit(desc_tx);
1038 	reinit_completion(&spi_imx->dma_tx_completion);
1039 	dma_async_issue_pending(master->dma_tx);
1040 
1041 	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1042 
1043 	/* Wait SDMA to finish the data transfer.*/
1044 	timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1045 						transfer_timeout);
1046 	if (!timeout) {
1047 		dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1048 		dmaengine_terminate_all(master->dma_tx);
1049 		dmaengine_terminate_all(master->dma_rx);
1050 		return -ETIMEDOUT;
1051 	}
1052 
1053 	timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1054 					      transfer_timeout);
1055 	if (!timeout) {
1056 		dev_err(&master->dev, "I/O Error in DMA RX\n");
1057 		spi_imx->devtype_data->reset(spi_imx);
1058 		dmaengine_terminate_all(master->dma_rx);
1059 		return -ETIMEDOUT;
1060 	}
1061 
1062 	return transfer->len;
1063 }
1064 
1065 static int spi_imx_pio_transfer(struct spi_device *spi,
1066 				struct spi_transfer *transfer)
1067 {
1068 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1069 	unsigned long transfer_timeout;
1070 	unsigned long timeout;
1071 
1072 	spi_imx->tx_buf = transfer->tx_buf;
1073 	spi_imx->rx_buf = transfer->rx_buf;
1074 	spi_imx->count = transfer->len;
1075 	spi_imx->txfifo = 0;
1076 
1077 	reinit_completion(&spi_imx->xfer_done);
1078 
1079 	spi_imx_push(spi_imx);
1080 
1081 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1082 
1083 	transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1084 
1085 	timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
1086 					      transfer_timeout);
1087 	if (!timeout) {
1088 		dev_err(&spi->dev, "I/O Error in PIO\n");
1089 		spi_imx->devtype_data->reset(spi_imx);
1090 		return -ETIMEDOUT;
1091 	}
1092 
1093 	return transfer->len;
1094 }
1095 
1096 static int spi_imx_transfer(struct spi_device *spi,
1097 				struct spi_transfer *transfer)
1098 {
1099 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1100 
1101 	if (spi_imx->usedma)
1102 		return spi_imx_dma_transfer(spi_imx, transfer);
1103 	else
1104 		return spi_imx_pio_transfer(spi, transfer);
1105 }
1106 
1107 static int spi_imx_setup(struct spi_device *spi)
1108 {
1109 	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1110 		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1111 
1112 	if (gpio_is_valid(spi->cs_gpio))
1113 		gpio_direction_output(spi->cs_gpio,
1114 				      spi->mode & SPI_CS_HIGH ? 0 : 1);
1115 
1116 	spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
1117 
1118 	return 0;
1119 }
1120 
1121 static void spi_imx_cleanup(struct spi_device *spi)
1122 {
1123 }
1124 
1125 static int
1126 spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1127 {
1128 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1129 	int ret;
1130 
1131 	ret = clk_enable(spi_imx->clk_per);
1132 	if (ret)
1133 		return ret;
1134 
1135 	ret = clk_enable(spi_imx->clk_ipg);
1136 	if (ret) {
1137 		clk_disable(spi_imx->clk_per);
1138 		return ret;
1139 	}
1140 
1141 	return 0;
1142 }
1143 
1144 static int
1145 spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1146 {
1147 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1148 
1149 	clk_disable(spi_imx->clk_ipg);
1150 	clk_disable(spi_imx->clk_per);
1151 	return 0;
1152 }
1153 
1154 static int spi_imx_probe(struct platform_device *pdev)
1155 {
1156 	struct device_node *np = pdev->dev.of_node;
1157 	const struct of_device_id *of_id =
1158 			of_match_device(spi_imx_dt_ids, &pdev->dev);
1159 	struct spi_imx_master *mxc_platform_info =
1160 			dev_get_platdata(&pdev->dev);
1161 	struct spi_master *master;
1162 	struct spi_imx_data *spi_imx;
1163 	struct resource *res;
1164 	int i, ret, irq, spi_drctl;
1165 
1166 	if (!np && !mxc_platform_info) {
1167 		dev_err(&pdev->dev, "can't get the platform data\n");
1168 		return -EINVAL;
1169 	}
1170 
1171 	master = spi_alloc_master(&pdev->dev, sizeof(struct spi_imx_data));
1172 	if (!master)
1173 		return -ENOMEM;
1174 
1175 	ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
1176 	if ((ret < 0) || (spi_drctl >= 0x3)) {
1177 		/* '11' is reserved */
1178 		spi_drctl = 0;
1179 	}
1180 
1181 	platform_set_drvdata(pdev, master);
1182 
1183 	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1184 	master->bus_num = np ? -1 : pdev->id;
1185 
1186 	spi_imx = spi_master_get_devdata(master);
1187 	spi_imx->bitbang.master = master;
1188 	spi_imx->dev = &pdev->dev;
1189 
1190 	spi_imx->devtype_data = of_id ? of_id->data :
1191 		(struct spi_imx_devtype_data *)pdev->id_entry->driver_data;
1192 
1193 	if (mxc_platform_info) {
1194 		master->num_chipselect = mxc_platform_info->num_chipselect;
1195 		master->cs_gpios = devm_kzalloc(&master->dev,
1196 			sizeof(int) * master->num_chipselect, GFP_KERNEL);
1197 		if (!master->cs_gpios)
1198 			return -ENOMEM;
1199 
1200 		for (i = 0; i < master->num_chipselect; i++)
1201 			master->cs_gpios[i] = mxc_platform_info->chipselect[i];
1202  	}
1203 
1204 	spi_imx->bitbang.chipselect = spi_imx_chipselect;
1205 	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1206 	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1207 	spi_imx->bitbang.master->setup = spi_imx_setup;
1208 	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1209 	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1210 	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1211 	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1212 	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx))
1213 		spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY;
1214 
1215 	spi_imx->spi_drctl = spi_drctl;
1216 
1217 	init_completion(&spi_imx->xfer_done);
1218 
1219 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1220 	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1221 	if (IS_ERR(spi_imx->base)) {
1222 		ret = PTR_ERR(spi_imx->base);
1223 		goto out_master_put;
1224 	}
1225 	spi_imx->base_phys = res->start;
1226 
1227 	irq = platform_get_irq(pdev, 0);
1228 	if (irq < 0) {
1229 		ret = irq;
1230 		goto out_master_put;
1231 	}
1232 
1233 	ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1234 			       dev_name(&pdev->dev), spi_imx);
1235 	if (ret) {
1236 		dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1237 		goto out_master_put;
1238 	}
1239 
1240 	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1241 	if (IS_ERR(spi_imx->clk_ipg)) {
1242 		ret = PTR_ERR(spi_imx->clk_ipg);
1243 		goto out_master_put;
1244 	}
1245 
1246 	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1247 	if (IS_ERR(spi_imx->clk_per)) {
1248 		ret = PTR_ERR(spi_imx->clk_per);
1249 		goto out_master_put;
1250 	}
1251 
1252 	ret = clk_prepare_enable(spi_imx->clk_per);
1253 	if (ret)
1254 		goto out_master_put;
1255 
1256 	ret = clk_prepare_enable(spi_imx->clk_ipg);
1257 	if (ret)
1258 		goto out_put_per;
1259 
1260 	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1261 	/*
1262 	 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1263 	 * if validated on other chips.
1264 	 */
1265 	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx)) {
1266 		ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
1267 		if (ret == -EPROBE_DEFER)
1268 			goto out_clk_put;
1269 
1270 		if (ret < 0)
1271 			dev_err(&pdev->dev, "dma setup error %d, use pio\n",
1272 				ret);
1273 	}
1274 
1275 	spi_imx->devtype_data->reset(spi_imx);
1276 
1277 	spi_imx->devtype_data->intctrl(spi_imx, 0);
1278 
1279 	master->dev.of_node = pdev->dev.of_node;
1280 	ret = spi_bitbang_start(&spi_imx->bitbang);
1281 	if (ret) {
1282 		dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
1283 		goto out_clk_put;
1284 	}
1285 
1286 	if (!master->cs_gpios) {
1287 		dev_err(&pdev->dev, "No CS GPIOs available\n");
1288 		ret = -EINVAL;
1289 		goto out_clk_put;
1290 	}
1291 
1292 	for (i = 0; i < master->num_chipselect; i++) {
1293 		if (!gpio_is_valid(master->cs_gpios[i]))
1294 			continue;
1295 
1296 		ret = devm_gpio_request(&pdev->dev, master->cs_gpios[i],
1297 					DRIVER_NAME);
1298 		if (ret) {
1299 			dev_err(&pdev->dev, "Can't get CS GPIO %i\n",
1300 				master->cs_gpios[i]);
1301 			goto out_clk_put;
1302 		}
1303 	}
1304 
1305 	dev_info(&pdev->dev, "probed\n");
1306 
1307 	clk_disable(spi_imx->clk_ipg);
1308 	clk_disable(spi_imx->clk_per);
1309 	return ret;
1310 
1311 out_clk_put:
1312 	clk_disable_unprepare(spi_imx->clk_ipg);
1313 out_put_per:
1314 	clk_disable_unprepare(spi_imx->clk_per);
1315 out_master_put:
1316 	spi_master_put(master);
1317 
1318 	return ret;
1319 }
1320 
1321 static int spi_imx_remove(struct platform_device *pdev)
1322 {
1323 	struct spi_master *master = platform_get_drvdata(pdev);
1324 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1325 
1326 	spi_bitbang_stop(&spi_imx->bitbang);
1327 
1328 	writel(0, spi_imx->base + MXC_CSPICTRL);
1329 	clk_unprepare(spi_imx->clk_ipg);
1330 	clk_unprepare(spi_imx->clk_per);
1331 	spi_imx_sdma_exit(spi_imx);
1332 	spi_master_put(master);
1333 
1334 	return 0;
1335 }
1336 
1337 static struct platform_driver spi_imx_driver = {
1338 	.driver = {
1339 		   .name = DRIVER_NAME,
1340 		   .of_match_table = spi_imx_dt_ids,
1341 		   },
1342 	.id_table = spi_imx_devtype,
1343 	.probe = spi_imx_probe,
1344 	.remove = spi_imx_remove,
1345 };
1346 module_platform_driver(spi_imx_driver);
1347 
1348 MODULE_DESCRIPTION("SPI Master Controller driver");
1349 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1350 MODULE_LICENSE("GPL");
1351 MODULE_ALIAS("platform:" DRIVER_NAME);
1352