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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 #define IMX_DMA_TIMEOUT (msecs_to_jiffies(3000))
60 struct spi_imx_config {
61 	unsigned int speed_hz;
62 	unsigned int bpw;
63 	unsigned int mode;
64 	u8 cs;
65 };
66 
67 enum spi_imx_devtype {
68 	IMX1_CSPI,
69 	IMX21_CSPI,
70 	IMX27_CSPI,
71 	IMX31_CSPI,
72 	IMX35_CSPI,	/* CSPI on all i.mx except above */
73 	IMX51_ECSPI,	/* ECSPI on i.mx51 and later */
74 };
75 
76 struct spi_imx_data;
77 
78 struct spi_imx_devtype_data {
79 	void (*intctrl)(struct spi_imx_data *, int);
80 	int (*config)(struct spi_imx_data *, struct spi_imx_config *);
81 	void (*trigger)(struct spi_imx_data *);
82 	int (*rx_available)(struct spi_imx_data *);
83 	void (*reset)(struct spi_imx_data *);
84 	enum spi_imx_devtype devtype;
85 };
86 
87 struct spi_imx_data {
88 	struct spi_bitbang bitbang;
89 
90 	struct completion xfer_done;
91 	void __iomem *base;
92 	int irq;
93 	struct clk *clk_per;
94 	struct clk *clk_ipg;
95 	unsigned long spi_clk;
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 	unsigned int dma_is_inited;
106 	unsigned int dma_finished;
107 	bool usedma;
108 	u32 rx_wml;
109 	u32 tx_wml;
110 	u32 rxt_wml;
111 	struct completion dma_rx_completion;
112 	struct completion dma_tx_completion;
113 
114 	const struct spi_imx_devtype_data *devtype_data;
115 	int chipselect[0];
116 };
117 
is_imx27_cspi(struct spi_imx_data * d)118 static inline int is_imx27_cspi(struct spi_imx_data *d)
119 {
120 	return d->devtype_data->devtype == IMX27_CSPI;
121 }
122 
is_imx35_cspi(struct spi_imx_data * d)123 static inline int is_imx35_cspi(struct spi_imx_data *d)
124 {
125 	return d->devtype_data->devtype == IMX35_CSPI;
126 }
127 
spi_imx_get_fifosize(struct spi_imx_data * d)128 static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d)
129 {
130 	return (d->devtype_data->devtype == IMX51_ECSPI) ? 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 */
spi_imx_clkdiv_1(unsigned int fin,unsigned int fspi,unsigned int max)173 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
174 		unsigned int fspi, unsigned int max)
175 {
176 	int i;
177 
178 	for (i = 2; i < max; i++)
179 		if (fspi * mxc_clkdivs[i] >= fin)
180 			return i;
181 
182 	return max;
183 }
184 
185 /* MX1, MX31, MX35, MX51 CSPI */
spi_imx_clkdiv_2(unsigned int fin,unsigned int fspi)186 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
187 		unsigned int fspi)
188 {
189 	int i, div = 4;
190 
191 	for (i = 0; i < 7; i++) {
192 		if (fspi * div >= fin)
193 			return i;
194 		div <<= 1;
195 	}
196 
197 	return 7;
198 }
199 
spi_imx_can_dma(struct spi_master * master,struct spi_device * spi,struct spi_transfer * transfer)200 static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
201 			 struct spi_transfer *transfer)
202 {
203 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
204 
205 	if (spi_imx->dma_is_inited && (transfer->len > spi_imx->rx_wml)
206 	    && (transfer->len > spi_imx->tx_wml))
207 		return true;
208 	return false;
209 }
210 
211 #define MX51_ECSPI_CTRL		0x08
212 #define MX51_ECSPI_CTRL_ENABLE		(1 <<  0)
213 #define MX51_ECSPI_CTRL_XCH		(1 <<  2)
214 #define MX51_ECSPI_CTRL_SMC		(1 << 3)
215 #define MX51_ECSPI_CTRL_MODE_MASK	(0xf << 4)
216 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET	8
217 #define MX51_ECSPI_CTRL_PREDIV_OFFSET	12
218 #define MX51_ECSPI_CTRL_CS(cs)		((cs) << 18)
219 #define MX51_ECSPI_CTRL_BL_OFFSET	20
220 
221 #define MX51_ECSPI_CONFIG	0x0c
222 #define MX51_ECSPI_CONFIG_SCLKPHA(cs)	(1 << ((cs) +  0))
223 #define MX51_ECSPI_CONFIG_SCLKPOL(cs)	(1 << ((cs) +  4))
224 #define MX51_ECSPI_CONFIG_SBBCTRL(cs)	(1 << ((cs) +  8))
225 #define MX51_ECSPI_CONFIG_SSBPOL(cs)	(1 << ((cs) + 12))
226 #define MX51_ECSPI_CONFIG_SCLKCTL(cs)	(1 << ((cs) + 20))
227 
228 #define MX51_ECSPI_INT		0x10
229 #define MX51_ECSPI_INT_TEEN		(1 <<  0)
230 #define MX51_ECSPI_INT_RREN		(1 <<  3)
231 
232 #define MX51_ECSPI_DMA      0x14
233 #define MX51_ECSPI_DMA_TX_WML_OFFSET	0
234 #define MX51_ECSPI_DMA_TX_WML_MASK	0x3F
235 #define MX51_ECSPI_DMA_RX_WML_OFFSET	16
236 #define MX51_ECSPI_DMA_RX_WML_MASK	(0x3F << 16)
237 #define MX51_ECSPI_DMA_RXT_WML_OFFSET	24
238 #define MX51_ECSPI_DMA_RXT_WML_MASK	(0x3F << 24)
239 
240 #define MX51_ECSPI_DMA_TEDEN_OFFSET	7
241 #define MX51_ECSPI_DMA_RXDEN_OFFSET	23
242 #define MX51_ECSPI_DMA_RXTDEN_OFFSET	31
243 
244 #define MX51_ECSPI_STAT		0x18
245 #define MX51_ECSPI_STAT_RR		(1 <<  3)
246 
247 /* MX51 eCSPI */
mx51_ecspi_clkdiv(unsigned int fin,unsigned int fspi,unsigned int * fres)248 static unsigned int mx51_ecspi_clkdiv(unsigned int fin, unsigned int fspi,
249 				      unsigned int *fres)
250 {
251 	/*
252 	 * there are two 4-bit dividers, the pre-divider divides by
253 	 * $pre, the post-divider by 2^$post
254 	 */
255 	unsigned int pre, post;
256 
257 	if (unlikely(fspi > fin))
258 		return 0;
259 
260 	post = fls(fin) - fls(fspi);
261 	if (fin > fspi << post)
262 		post++;
263 
264 	/* now we have: (fin <= fspi << post) with post being minimal */
265 
266 	post = max(4U, post) - 4;
267 	if (unlikely(post > 0xf)) {
268 		pr_err("%s: cannot set clock freq: %u (base freq: %u)\n",
269 				__func__, fspi, fin);
270 		return 0xff;
271 	}
272 
273 	pre = DIV_ROUND_UP(fin, fspi << post) - 1;
274 
275 	pr_debug("%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
276 			__func__, fin, fspi, post, pre);
277 
278 	/* Resulting frequency for the SCLK line. */
279 	*fres = (fin / (pre + 1)) >> post;
280 
281 	return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
282 		(post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
283 }
284 
mx51_ecspi_intctrl(struct spi_imx_data * spi_imx,int enable)285 static void __maybe_unused mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
286 {
287 	unsigned val = 0;
288 
289 	if (enable & MXC_INT_TE)
290 		val |= MX51_ECSPI_INT_TEEN;
291 
292 	if (enable & MXC_INT_RR)
293 		val |= MX51_ECSPI_INT_RREN;
294 
295 	writel(val, spi_imx->base + MX51_ECSPI_INT);
296 }
297 
mx51_ecspi_trigger(struct spi_imx_data * spi_imx)298 static void __maybe_unused mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
299 {
300 	u32 reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
301 
302 	if (!spi_imx->usedma)
303 		reg |= MX51_ECSPI_CTRL_XCH;
304 	else if (!spi_imx->dma_finished)
305 		reg |= MX51_ECSPI_CTRL_SMC;
306 	else
307 		reg &= ~MX51_ECSPI_CTRL_SMC;
308 	writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
309 }
310 
mx51_ecspi_config(struct spi_imx_data * spi_imx,struct spi_imx_config * config)311 static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx,
312 		struct spi_imx_config *config)
313 {
314 	u32 ctrl = MX51_ECSPI_CTRL_ENABLE, cfg = 0, dma = 0;
315 	u32 tx_wml_cfg, rx_wml_cfg, rxt_wml_cfg;
316 	u32 clk = config->speed_hz, delay;
317 
318 	/*
319 	 * The hardware seems to have a race condition when changing modes. The
320 	 * current assumption is that the selection of the channel arrives
321 	 * earlier in the hardware than the mode bits when they are written at
322 	 * the same time.
323 	 * So set master mode for all channels as we do not support slave mode.
324 	 */
325 	ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
326 
327 	/* set clock speed */
328 	ctrl |= mx51_ecspi_clkdiv(spi_imx->spi_clk, config->speed_hz, &clk);
329 
330 	/* set chip select to use */
331 	ctrl |= MX51_ECSPI_CTRL_CS(config->cs);
332 
333 	ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET;
334 
335 	cfg |= MX51_ECSPI_CONFIG_SBBCTRL(config->cs);
336 
337 	if (config->mode & SPI_CPHA)
338 		cfg |= MX51_ECSPI_CONFIG_SCLKPHA(config->cs);
339 
340 	if (config->mode & SPI_CPOL) {
341 		cfg |= MX51_ECSPI_CONFIG_SCLKPOL(config->cs);
342 		cfg |= MX51_ECSPI_CONFIG_SCLKCTL(config->cs);
343 	}
344 	if (config->mode & SPI_CS_HIGH)
345 		cfg |= MX51_ECSPI_CONFIG_SSBPOL(config->cs);
346 
347 	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
348 	writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
349 
350 	/*
351 	 * Wait until the changes in the configuration register CONFIGREG
352 	 * propagate into the hardware. It takes exactly one tick of the
353 	 * SCLK clock, but we will wait two SCLK clock just to be sure. The
354 	 * effect of the delay it takes for the hardware to apply changes
355 	 * is noticable if the SCLK clock run very slow. In such a case, if
356 	 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
357 	 * be asserted before the SCLK polarity changes, which would disrupt
358 	 * the SPI communication as the device on the other end would consider
359 	 * the change of SCLK polarity as a clock tick already.
360 	 */
361 	delay = (2 * 1000000) / clk;
362 	if (likely(delay < 10))	/* SCLK is faster than 100 kHz */
363 		udelay(delay);
364 	else			/* SCLK is _very_ slow */
365 		usleep_range(delay, delay + 10);
366 
367 	/*
368 	 * Configure the DMA register: setup the watermark
369 	 * and enable DMA request.
370 	 */
371 	if (spi_imx->dma_is_inited) {
372 		dma = readl(spi_imx->base + MX51_ECSPI_DMA);
373 
374 		spi_imx->rxt_wml = spi_imx_get_fifosize(spi_imx) / 2;
375 		rx_wml_cfg = spi_imx->rx_wml << MX51_ECSPI_DMA_RX_WML_OFFSET;
376 		tx_wml_cfg = spi_imx->tx_wml << MX51_ECSPI_DMA_TX_WML_OFFSET;
377 		rxt_wml_cfg = spi_imx->rxt_wml << MX51_ECSPI_DMA_RXT_WML_OFFSET;
378 		dma = (dma & ~MX51_ECSPI_DMA_TX_WML_MASK
379 			   & ~MX51_ECSPI_DMA_RX_WML_MASK
380 			   & ~MX51_ECSPI_DMA_RXT_WML_MASK)
381 			   | rx_wml_cfg | tx_wml_cfg | rxt_wml_cfg
382 			   |(1 << MX51_ECSPI_DMA_TEDEN_OFFSET)
383 			   |(1 << MX51_ECSPI_DMA_RXDEN_OFFSET)
384 			   |(1 << MX51_ECSPI_DMA_RXTDEN_OFFSET);
385 
386 		writel(dma, spi_imx->base + MX51_ECSPI_DMA);
387 	}
388 
389 	return 0;
390 }
391 
mx51_ecspi_rx_available(struct spi_imx_data * spi_imx)392 static int __maybe_unused mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
393 {
394 	return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
395 }
396 
mx51_ecspi_reset(struct spi_imx_data * spi_imx)397 static void __maybe_unused mx51_ecspi_reset(struct spi_imx_data *spi_imx)
398 {
399 	/* drain receive buffer */
400 	while (mx51_ecspi_rx_available(spi_imx))
401 		readl(spi_imx->base + MXC_CSPIRXDATA);
402 }
403 
404 #define MX31_INTREG_TEEN	(1 << 0)
405 #define MX31_INTREG_RREN	(1 << 3)
406 
407 #define MX31_CSPICTRL_ENABLE	(1 << 0)
408 #define MX31_CSPICTRL_MASTER	(1 << 1)
409 #define MX31_CSPICTRL_XCH	(1 << 2)
410 #define MX31_CSPICTRL_POL	(1 << 4)
411 #define MX31_CSPICTRL_PHA	(1 << 5)
412 #define MX31_CSPICTRL_SSCTL	(1 << 6)
413 #define MX31_CSPICTRL_SSPOL	(1 << 7)
414 #define MX31_CSPICTRL_BC_SHIFT	8
415 #define MX35_CSPICTRL_BL_SHIFT	20
416 #define MX31_CSPICTRL_CS_SHIFT	24
417 #define MX35_CSPICTRL_CS_SHIFT	12
418 #define MX31_CSPICTRL_DR_SHIFT	16
419 
420 #define MX31_CSPISTATUS		0x14
421 #define MX31_STATUS_RR		(1 << 3)
422 
423 /* These functions also work for the i.MX35, but be aware that
424  * the i.MX35 has a slightly different register layout for bits
425  * we do not use here.
426  */
mx31_intctrl(struct spi_imx_data * spi_imx,int enable)427 static void __maybe_unused mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
428 {
429 	unsigned int val = 0;
430 
431 	if (enable & MXC_INT_TE)
432 		val |= MX31_INTREG_TEEN;
433 	if (enable & MXC_INT_RR)
434 		val |= MX31_INTREG_RREN;
435 
436 	writel(val, spi_imx->base + MXC_CSPIINT);
437 }
438 
mx31_trigger(struct spi_imx_data * spi_imx)439 static void __maybe_unused mx31_trigger(struct spi_imx_data *spi_imx)
440 {
441 	unsigned int reg;
442 
443 	reg = readl(spi_imx->base + MXC_CSPICTRL);
444 	reg |= MX31_CSPICTRL_XCH;
445 	writel(reg, spi_imx->base + MXC_CSPICTRL);
446 }
447 
mx31_config(struct spi_imx_data * spi_imx,struct spi_imx_config * config)448 static int __maybe_unused mx31_config(struct spi_imx_data *spi_imx,
449 		struct spi_imx_config *config)
450 {
451 	unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
452 	int cs = spi_imx->chipselect[config->cs];
453 
454 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
455 		MX31_CSPICTRL_DR_SHIFT;
456 
457 	if (is_imx35_cspi(spi_imx)) {
458 		reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT;
459 		reg |= MX31_CSPICTRL_SSCTL;
460 	} else {
461 		reg |= (config->bpw - 1) << MX31_CSPICTRL_BC_SHIFT;
462 	}
463 
464 	if (config->mode & SPI_CPHA)
465 		reg |= MX31_CSPICTRL_PHA;
466 	if (config->mode & SPI_CPOL)
467 		reg |= MX31_CSPICTRL_POL;
468 	if (config->mode & SPI_CS_HIGH)
469 		reg |= MX31_CSPICTRL_SSPOL;
470 	if (cs < 0)
471 		reg |= (cs + 32) <<
472 			(is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
473 						  MX31_CSPICTRL_CS_SHIFT);
474 
475 	writel(reg, spi_imx->base + MXC_CSPICTRL);
476 
477 	return 0;
478 }
479 
mx31_rx_available(struct spi_imx_data * spi_imx)480 static int __maybe_unused mx31_rx_available(struct spi_imx_data *spi_imx)
481 {
482 	return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
483 }
484 
mx31_reset(struct spi_imx_data * spi_imx)485 static void __maybe_unused mx31_reset(struct spi_imx_data *spi_imx)
486 {
487 	/* drain receive buffer */
488 	while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
489 		readl(spi_imx->base + MXC_CSPIRXDATA);
490 }
491 
492 #define MX21_INTREG_RR		(1 << 4)
493 #define MX21_INTREG_TEEN	(1 << 9)
494 #define MX21_INTREG_RREN	(1 << 13)
495 
496 #define MX21_CSPICTRL_POL	(1 << 5)
497 #define MX21_CSPICTRL_PHA	(1 << 6)
498 #define MX21_CSPICTRL_SSPOL	(1 << 8)
499 #define MX21_CSPICTRL_XCH	(1 << 9)
500 #define MX21_CSPICTRL_ENABLE	(1 << 10)
501 #define MX21_CSPICTRL_MASTER	(1 << 11)
502 #define MX21_CSPICTRL_DR_SHIFT	14
503 #define MX21_CSPICTRL_CS_SHIFT	19
504 
mx21_intctrl(struct spi_imx_data * spi_imx,int enable)505 static void __maybe_unused mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
506 {
507 	unsigned int val = 0;
508 
509 	if (enable & MXC_INT_TE)
510 		val |= MX21_INTREG_TEEN;
511 	if (enable & MXC_INT_RR)
512 		val |= MX21_INTREG_RREN;
513 
514 	writel(val, spi_imx->base + MXC_CSPIINT);
515 }
516 
mx21_trigger(struct spi_imx_data * spi_imx)517 static void __maybe_unused mx21_trigger(struct spi_imx_data *spi_imx)
518 {
519 	unsigned int reg;
520 
521 	reg = readl(spi_imx->base + MXC_CSPICTRL);
522 	reg |= MX21_CSPICTRL_XCH;
523 	writel(reg, spi_imx->base + MXC_CSPICTRL);
524 }
525 
mx21_config(struct spi_imx_data * spi_imx,struct spi_imx_config * config)526 static int __maybe_unused mx21_config(struct spi_imx_data *spi_imx,
527 		struct spi_imx_config *config)
528 {
529 	unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
530 	int cs = spi_imx->chipselect[config->cs];
531 	unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
532 
533 	reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max) <<
534 		MX21_CSPICTRL_DR_SHIFT;
535 	reg |= config->bpw - 1;
536 
537 	if (config->mode & SPI_CPHA)
538 		reg |= MX21_CSPICTRL_PHA;
539 	if (config->mode & SPI_CPOL)
540 		reg |= MX21_CSPICTRL_POL;
541 	if (config->mode & SPI_CS_HIGH)
542 		reg |= MX21_CSPICTRL_SSPOL;
543 	if (cs < 0)
544 		reg |= (cs + 32) << MX21_CSPICTRL_CS_SHIFT;
545 
546 	writel(reg, spi_imx->base + MXC_CSPICTRL);
547 
548 	return 0;
549 }
550 
mx21_rx_available(struct spi_imx_data * spi_imx)551 static int __maybe_unused mx21_rx_available(struct spi_imx_data *spi_imx)
552 {
553 	return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
554 }
555 
mx21_reset(struct spi_imx_data * spi_imx)556 static void __maybe_unused mx21_reset(struct spi_imx_data *spi_imx)
557 {
558 	writel(1, spi_imx->base + MXC_RESET);
559 }
560 
561 #define MX1_INTREG_RR		(1 << 3)
562 #define MX1_INTREG_TEEN		(1 << 8)
563 #define MX1_INTREG_RREN		(1 << 11)
564 
565 #define MX1_CSPICTRL_POL	(1 << 4)
566 #define MX1_CSPICTRL_PHA	(1 << 5)
567 #define MX1_CSPICTRL_XCH	(1 << 8)
568 #define MX1_CSPICTRL_ENABLE	(1 << 9)
569 #define MX1_CSPICTRL_MASTER	(1 << 10)
570 #define MX1_CSPICTRL_DR_SHIFT	13
571 
mx1_intctrl(struct spi_imx_data * spi_imx,int enable)572 static void __maybe_unused mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
573 {
574 	unsigned int val = 0;
575 
576 	if (enable & MXC_INT_TE)
577 		val |= MX1_INTREG_TEEN;
578 	if (enable & MXC_INT_RR)
579 		val |= MX1_INTREG_RREN;
580 
581 	writel(val, spi_imx->base + MXC_CSPIINT);
582 }
583 
mx1_trigger(struct spi_imx_data * spi_imx)584 static void __maybe_unused mx1_trigger(struct spi_imx_data *spi_imx)
585 {
586 	unsigned int reg;
587 
588 	reg = readl(spi_imx->base + MXC_CSPICTRL);
589 	reg |= MX1_CSPICTRL_XCH;
590 	writel(reg, spi_imx->base + MXC_CSPICTRL);
591 }
592 
mx1_config(struct spi_imx_data * spi_imx,struct spi_imx_config * config)593 static int __maybe_unused mx1_config(struct spi_imx_data *spi_imx,
594 		struct spi_imx_config *config)
595 {
596 	unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
597 
598 	reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
599 		MX1_CSPICTRL_DR_SHIFT;
600 	reg |= config->bpw - 1;
601 
602 	if (config->mode & SPI_CPHA)
603 		reg |= MX1_CSPICTRL_PHA;
604 	if (config->mode & SPI_CPOL)
605 		reg |= MX1_CSPICTRL_POL;
606 
607 	writel(reg, spi_imx->base + MXC_CSPICTRL);
608 
609 	return 0;
610 }
611 
mx1_rx_available(struct spi_imx_data * spi_imx)612 static int __maybe_unused mx1_rx_available(struct spi_imx_data *spi_imx)
613 {
614 	return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
615 }
616 
mx1_reset(struct spi_imx_data * spi_imx)617 static void __maybe_unused mx1_reset(struct spi_imx_data *spi_imx)
618 {
619 	writel(1, spi_imx->base + MXC_RESET);
620 }
621 
622 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
623 	.intctrl = mx1_intctrl,
624 	.config = mx1_config,
625 	.trigger = mx1_trigger,
626 	.rx_available = mx1_rx_available,
627 	.reset = mx1_reset,
628 	.devtype = IMX1_CSPI,
629 };
630 
631 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
632 	.intctrl = mx21_intctrl,
633 	.config = mx21_config,
634 	.trigger = mx21_trigger,
635 	.rx_available = mx21_rx_available,
636 	.reset = mx21_reset,
637 	.devtype = IMX21_CSPI,
638 };
639 
640 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
641 	/* i.mx27 cspi shares the functions with i.mx21 one */
642 	.intctrl = mx21_intctrl,
643 	.config = mx21_config,
644 	.trigger = mx21_trigger,
645 	.rx_available = mx21_rx_available,
646 	.reset = mx21_reset,
647 	.devtype = IMX27_CSPI,
648 };
649 
650 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
651 	.intctrl = mx31_intctrl,
652 	.config = mx31_config,
653 	.trigger = mx31_trigger,
654 	.rx_available = mx31_rx_available,
655 	.reset = mx31_reset,
656 	.devtype = IMX31_CSPI,
657 };
658 
659 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
660 	/* i.mx35 and later cspi shares the functions with i.mx31 one */
661 	.intctrl = mx31_intctrl,
662 	.config = mx31_config,
663 	.trigger = mx31_trigger,
664 	.rx_available = mx31_rx_available,
665 	.reset = mx31_reset,
666 	.devtype = IMX35_CSPI,
667 };
668 
669 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
670 	.intctrl = mx51_ecspi_intctrl,
671 	.config = mx51_ecspi_config,
672 	.trigger = mx51_ecspi_trigger,
673 	.rx_available = mx51_ecspi_rx_available,
674 	.reset = mx51_ecspi_reset,
675 	.devtype = IMX51_ECSPI,
676 };
677 
678 static struct platform_device_id spi_imx_devtype[] = {
679 	{
680 		.name = "imx1-cspi",
681 		.driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
682 	}, {
683 		.name = "imx21-cspi",
684 		.driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
685 	}, {
686 		.name = "imx27-cspi",
687 		.driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
688 	}, {
689 		.name = "imx31-cspi",
690 		.driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
691 	}, {
692 		.name = "imx35-cspi",
693 		.driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
694 	}, {
695 		.name = "imx51-ecspi",
696 		.driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
697 	}, {
698 		/* sentinel */
699 	}
700 };
701 
702 static const struct of_device_id spi_imx_dt_ids[] = {
703 	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
704 	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
705 	{ .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
706 	{ .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
707 	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
708 	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
709 	{ /* sentinel */ }
710 };
711 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
712 
spi_imx_chipselect(struct spi_device * spi,int is_active)713 static void spi_imx_chipselect(struct spi_device *spi, int is_active)
714 {
715 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
716 	int gpio = spi_imx->chipselect[spi->chip_select];
717 	int active = is_active != BITBANG_CS_INACTIVE;
718 	int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
719 
720 	if (!gpio_is_valid(gpio))
721 		return;
722 
723 	gpio_set_value(gpio, dev_is_lowactive ^ active);
724 }
725 
spi_imx_push(struct spi_imx_data * spi_imx)726 static void spi_imx_push(struct spi_imx_data *spi_imx)
727 {
728 	while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) {
729 		if (!spi_imx->count)
730 			break;
731 		spi_imx->tx(spi_imx);
732 		spi_imx->txfifo++;
733 	}
734 
735 	spi_imx->devtype_data->trigger(spi_imx);
736 }
737 
spi_imx_isr(int irq,void * dev_id)738 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
739 {
740 	struct spi_imx_data *spi_imx = dev_id;
741 
742 	while (spi_imx->devtype_data->rx_available(spi_imx)) {
743 		spi_imx->rx(spi_imx);
744 		spi_imx->txfifo--;
745 	}
746 
747 	if (spi_imx->count) {
748 		spi_imx_push(spi_imx);
749 		return IRQ_HANDLED;
750 	}
751 
752 	if (spi_imx->txfifo) {
753 		/* No data left to push, but still waiting for rx data,
754 		 * enable receive data available interrupt.
755 		 */
756 		spi_imx->devtype_data->intctrl(
757 				spi_imx, MXC_INT_RR);
758 		return IRQ_HANDLED;
759 	}
760 
761 	spi_imx->devtype_data->intctrl(spi_imx, 0);
762 	complete(&spi_imx->xfer_done);
763 
764 	return IRQ_HANDLED;
765 }
766 
spi_imx_setupxfer(struct spi_device * spi,struct spi_transfer * t)767 static int spi_imx_setupxfer(struct spi_device *spi,
768 				 struct spi_transfer *t)
769 {
770 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
771 	struct spi_imx_config config;
772 
773 	config.bpw = t ? t->bits_per_word : spi->bits_per_word;
774 	config.speed_hz  = t ? t->speed_hz : spi->max_speed_hz;
775 	config.mode = spi->mode;
776 	config.cs = spi->chip_select;
777 
778 	if (!config.speed_hz)
779 		config.speed_hz = spi->max_speed_hz;
780 	if (!config.bpw)
781 		config.bpw = spi->bits_per_word;
782 
783 	/* Initialize the functions for transfer */
784 	if (config.bpw <= 8) {
785 		spi_imx->rx = spi_imx_buf_rx_u8;
786 		spi_imx->tx = spi_imx_buf_tx_u8;
787 	} else if (config.bpw <= 16) {
788 		spi_imx->rx = spi_imx_buf_rx_u16;
789 		spi_imx->tx = spi_imx_buf_tx_u16;
790 	} else {
791 		spi_imx->rx = spi_imx_buf_rx_u32;
792 		spi_imx->tx = spi_imx_buf_tx_u32;
793 	}
794 
795 	spi_imx->devtype_data->config(spi_imx, &config);
796 
797 	return 0;
798 }
799 
spi_imx_sdma_exit(struct spi_imx_data * spi_imx)800 static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
801 {
802 	struct spi_master *master = spi_imx->bitbang.master;
803 
804 	if (master->dma_rx) {
805 		dma_release_channel(master->dma_rx);
806 		master->dma_rx = NULL;
807 	}
808 
809 	if (master->dma_tx) {
810 		dma_release_channel(master->dma_tx);
811 		master->dma_tx = NULL;
812 	}
813 
814 	spi_imx->dma_is_inited = 0;
815 }
816 
spi_imx_sdma_init(struct device * dev,struct spi_imx_data * spi_imx,struct spi_master * master,const struct resource * res)817 static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
818 			     struct spi_master *master,
819 			     const struct resource *res)
820 {
821 	struct dma_slave_config slave_config = {};
822 	int ret;
823 
824 	/* use pio mode for i.mx6dl chip TKT238285 */
825 	if (of_machine_is_compatible("fsl,imx6dl"))
826 		return 0;
827 
828 	/* Prepare for TX DMA: */
829 	master->dma_tx = dma_request_slave_channel(dev, "tx");
830 	if (!master->dma_tx) {
831 		dev_err(dev, "cannot get the TX DMA channel!\n");
832 		ret = -EINVAL;
833 		goto err;
834 	}
835 
836 	slave_config.direction = DMA_MEM_TO_DEV;
837 	slave_config.dst_addr = res->start + MXC_CSPITXDATA;
838 	slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
839 	slave_config.dst_maxburst = spi_imx_get_fifosize(spi_imx) / 2;
840 	ret = dmaengine_slave_config(master->dma_tx, &slave_config);
841 	if (ret) {
842 		dev_err(dev, "error in TX dma configuration.\n");
843 		goto err;
844 	}
845 
846 	/* Prepare for RX : */
847 	master->dma_rx = dma_request_slave_channel(dev, "rx");
848 	if (!master->dma_rx) {
849 		dev_dbg(dev, "cannot get the DMA channel.\n");
850 		ret = -EINVAL;
851 		goto err;
852 	}
853 
854 	slave_config.direction = DMA_DEV_TO_MEM;
855 	slave_config.src_addr = res->start + MXC_CSPIRXDATA;
856 	slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
857 	slave_config.src_maxburst = spi_imx_get_fifosize(spi_imx) / 2;
858 	ret = dmaengine_slave_config(master->dma_rx, &slave_config);
859 	if (ret) {
860 		dev_err(dev, "error in RX dma configuration.\n");
861 		goto err;
862 	}
863 
864 	init_completion(&spi_imx->dma_rx_completion);
865 	init_completion(&spi_imx->dma_tx_completion);
866 	master->can_dma = spi_imx_can_dma;
867 	master->max_dma_len = MAX_SDMA_BD_BYTES;
868 	spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
869 					 SPI_MASTER_MUST_TX;
870 	spi_imx->tx_wml = spi_imx_get_fifosize(spi_imx) / 2;
871 	spi_imx->rx_wml = spi_imx_get_fifosize(spi_imx) / 2;
872 	spi_imx->dma_is_inited = 1;
873 
874 	return 0;
875 err:
876 	spi_imx_sdma_exit(spi_imx);
877 	return ret;
878 }
879 
spi_imx_dma_rx_callback(void * cookie)880 static void spi_imx_dma_rx_callback(void *cookie)
881 {
882 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
883 
884 	complete(&spi_imx->dma_rx_completion);
885 }
886 
spi_imx_dma_tx_callback(void * cookie)887 static void spi_imx_dma_tx_callback(void *cookie)
888 {
889 	struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
890 
891 	complete(&spi_imx->dma_tx_completion);
892 }
893 
spi_imx_dma_transfer(struct spi_imx_data * spi_imx,struct spi_transfer * transfer)894 static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
895 				struct spi_transfer *transfer)
896 {
897 	struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
898 	int ret;
899 	u32 dma;
900 	int left;
901 	struct spi_master *master = spi_imx->bitbang.master;
902 	struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
903 
904 	if (tx) {
905 		desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
906 					tx->sgl, tx->nents, DMA_TO_DEVICE,
907 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
908 		if (!desc_tx)
909 			goto no_dma;
910 
911 		desc_tx->callback = spi_imx_dma_tx_callback;
912 		desc_tx->callback_param = (void *)spi_imx;
913 		dmaengine_submit(desc_tx);
914 	}
915 
916 	if (rx) {
917 		desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
918 					rx->sgl, rx->nents, DMA_FROM_DEVICE,
919 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
920 		if (!desc_rx)
921 			goto no_dma;
922 
923 		desc_rx->callback = spi_imx_dma_rx_callback;
924 		desc_rx->callback_param = (void *)spi_imx;
925 		dmaengine_submit(desc_rx);
926 	}
927 
928 	reinit_completion(&spi_imx->dma_rx_completion);
929 	reinit_completion(&spi_imx->dma_tx_completion);
930 
931 	/* Trigger the cspi module. */
932 	spi_imx->dma_finished = 0;
933 
934 	dma = readl(spi_imx->base + MX51_ECSPI_DMA);
935 	dma = dma & (~MX51_ECSPI_DMA_RXT_WML_MASK);
936 	/* Change RX_DMA_LENGTH trigger dma fetch tail data */
937 	left = transfer->len % spi_imx->rxt_wml;
938 	if (left)
939 		writel(dma | (left << MX51_ECSPI_DMA_RXT_WML_OFFSET),
940 				spi_imx->base + MX51_ECSPI_DMA);
941 	spi_imx->devtype_data->trigger(spi_imx);
942 
943 	dma_async_issue_pending(master->dma_tx);
944 	dma_async_issue_pending(master->dma_rx);
945 	/* Wait SDMA to finish the data transfer.*/
946 	ret = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
947 						IMX_DMA_TIMEOUT);
948 	if (!ret) {
949 		pr_warn("%s %s: I/O Error in DMA TX\n",
950 			dev_driver_string(&master->dev),
951 			dev_name(&master->dev));
952 		dmaengine_terminate_all(master->dma_tx);
953 	} else {
954 		ret = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
955 				IMX_DMA_TIMEOUT);
956 		if (!ret) {
957 			pr_warn("%s %s: I/O Error in DMA RX\n",
958 				dev_driver_string(&master->dev),
959 				dev_name(&master->dev));
960 			spi_imx->devtype_data->reset(spi_imx);
961 			dmaengine_terminate_all(master->dma_rx);
962 		}
963 		writel(dma |
964 		       spi_imx->rxt_wml << MX51_ECSPI_DMA_RXT_WML_OFFSET,
965 		       spi_imx->base + MX51_ECSPI_DMA);
966 	}
967 
968 	spi_imx->dma_finished = 1;
969 	spi_imx->devtype_data->trigger(spi_imx);
970 
971 	if (!ret)
972 		ret = -ETIMEDOUT;
973 	else if (ret > 0)
974 		ret = transfer->len;
975 
976 	return ret;
977 
978 no_dma:
979 	pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
980 		     dev_driver_string(&master->dev),
981 		     dev_name(&master->dev));
982 	return -EAGAIN;
983 }
984 
spi_imx_pio_transfer(struct spi_device * spi,struct spi_transfer * transfer)985 static int spi_imx_pio_transfer(struct spi_device *spi,
986 				struct spi_transfer *transfer)
987 {
988 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
989 
990 	spi_imx->tx_buf = transfer->tx_buf;
991 	spi_imx->rx_buf = transfer->rx_buf;
992 	spi_imx->count = transfer->len;
993 	spi_imx->txfifo = 0;
994 
995 	reinit_completion(&spi_imx->xfer_done);
996 
997 	spi_imx_push(spi_imx);
998 
999 	spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1000 
1001 	wait_for_completion(&spi_imx->xfer_done);
1002 
1003 	return transfer->len;
1004 }
1005 
spi_imx_transfer(struct spi_device * spi,struct spi_transfer * transfer)1006 static int spi_imx_transfer(struct spi_device *spi,
1007 				struct spi_transfer *transfer)
1008 {
1009 	int ret;
1010 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1011 
1012 	if (spi_imx->bitbang.master->can_dma &&
1013 	    spi_imx_can_dma(spi_imx->bitbang.master, spi, transfer)) {
1014 		spi_imx->usedma = true;
1015 		ret = spi_imx_dma_transfer(spi_imx, transfer);
1016 		if (ret != -EAGAIN)
1017 			return ret;
1018 	}
1019 	spi_imx->usedma = false;
1020 
1021 	return spi_imx_pio_transfer(spi, transfer);
1022 }
1023 
spi_imx_setup(struct spi_device * spi)1024 static int spi_imx_setup(struct spi_device *spi)
1025 {
1026 	struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1027 	int gpio = spi_imx->chipselect[spi->chip_select];
1028 
1029 	dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1030 		 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1031 
1032 	if (gpio_is_valid(gpio))
1033 		gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
1034 
1035 	spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
1036 
1037 	return 0;
1038 }
1039 
spi_imx_cleanup(struct spi_device * spi)1040 static void spi_imx_cleanup(struct spi_device *spi)
1041 {
1042 }
1043 
1044 static int
spi_imx_prepare_message(struct spi_master * master,struct spi_message * msg)1045 spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1046 {
1047 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1048 	int ret;
1049 
1050 	ret = clk_enable(spi_imx->clk_per);
1051 	if (ret)
1052 		return ret;
1053 
1054 	ret = clk_enable(spi_imx->clk_ipg);
1055 	if (ret) {
1056 		clk_disable(spi_imx->clk_per);
1057 		return ret;
1058 	}
1059 
1060 	return 0;
1061 }
1062 
1063 static int
spi_imx_unprepare_message(struct spi_master * master,struct spi_message * msg)1064 spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1065 {
1066 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1067 
1068 	clk_disable(spi_imx->clk_ipg);
1069 	clk_disable(spi_imx->clk_per);
1070 	return 0;
1071 }
1072 
spi_imx_probe(struct platform_device * pdev)1073 static int spi_imx_probe(struct platform_device *pdev)
1074 {
1075 	struct device_node *np = pdev->dev.of_node;
1076 	const struct of_device_id *of_id =
1077 			of_match_device(spi_imx_dt_ids, &pdev->dev);
1078 	struct spi_imx_master *mxc_platform_info =
1079 			dev_get_platdata(&pdev->dev);
1080 	struct spi_master *master;
1081 	struct spi_imx_data *spi_imx;
1082 	struct resource *res;
1083 	int i, ret, num_cs;
1084 
1085 	if (!np && !mxc_platform_info) {
1086 		dev_err(&pdev->dev, "can't get the platform data\n");
1087 		return -EINVAL;
1088 	}
1089 
1090 	ret = of_property_read_u32(np, "fsl,spi-num-chipselects", &num_cs);
1091 	if (ret < 0) {
1092 		if (mxc_platform_info)
1093 			num_cs = mxc_platform_info->num_chipselect;
1094 		else
1095 			return ret;
1096 	}
1097 
1098 	master = spi_alloc_master(&pdev->dev,
1099 			sizeof(struct spi_imx_data) + sizeof(int) * num_cs);
1100 	if (!master)
1101 		return -ENOMEM;
1102 
1103 	platform_set_drvdata(pdev, master);
1104 
1105 	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1106 	master->bus_num = pdev->id;
1107 	master->num_chipselect = num_cs;
1108 
1109 	spi_imx = spi_master_get_devdata(master);
1110 	spi_imx->bitbang.master = master;
1111 
1112 	for (i = 0; i < master->num_chipselect; i++) {
1113 		int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
1114 		if (!gpio_is_valid(cs_gpio) && mxc_platform_info)
1115 			cs_gpio = mxc_platform_info->chipselect[i];
1116 
1117 		spi_imx->chipselect[i] = cs_gpio;
1118 		if (!gpio_is_valid(cs_gpio))
1119 			continue;
1120 
1121 		ret = devm_gpio_request(&pdev->dev, spi_imx->chipselect[i],
1122 					DRIVER_NAME);
1123 		if (ret) {
1124 			dev_err(&pdev->dev, "can't get cs gpios\n");
1125 			goto out_master_put;
1126 		}
1127 	}
1128 
1129 	spi_imx->bitbang.chipselect = spi_imx_chipselect;
1130 	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1131 	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1132 	spi_imx->bitbang.master->setup = spi_imx_setup;
1133 	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1134 	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1135 	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1136 	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1137 
1138 	init_completion(&spi_imx->xfer_done);
1139 
1140 	spi_imx->devtype_data = of_id ? of_id->data :
1141 		(struct spi_imx_devtype_data *) pdev->id_entry->driver_data;
1142 
1143 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1144 	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1145 	if (IS_ERR(spi_imx->base)) {
1146 		ret = PTR_ERR(spi_imx->base);
1147 		goto out_master_put;
1148 	}
1149 
1150 	spi_imx->irq = platform_get_irq(pdev, 0);
1151 	if (spi_imx->irq < 0) {
1152 		ret = spi_imx->irq;
1153 		goto out_master_put;
1154 	}
1155 
1156 	ret = devm_request_irq(&pdev->dev, spi_imx->irq, spi_imx_isr, 0,
1157 			       dev_name(&pdev->dev), spi_imx);
1158 	if (ret) {
1159 		dev_err(&pdev->dev, "can't get irq%d: %d\n", spi_imx->irq, ret);
1160 		goto out_master_put;
1161 	}
1162 
1163 	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1164 	if (IS_ERR(spi_imx->clk_ipg)) {
1165 		ret = PTR_ERR(spi_imx->clk_ipg);
1166 		goto out_master_put;
1167 	}
1168 
1169 	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1170 	if (IS_ERR(spi_imx->clk_per)) {
1171 		ret = PTR_ERR(spi_imx->clk_per);
1172 		goto out_master_put;
1173 	}
1174 
1175 	ret = clk_prepare_enable(spi_imx->clk_per);
1176 	if (ret)
1177 		goto out_master_put;
1178 
1179 	ret = clk_prepare_enable(spi_imx->clk_ipg);
1180 	if (ret)
1181 		goto out_put_per;
1182 
1183 	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1184 	/*
1185 	 * Only validated on i.mx6 now, can remove the constrain if validated on
1186 	 * other chips.
1187 	 */
1188 	if (spi_imx->devtype_data == &imx51_ecspi_devtype_data
1189 	    && spi_imx_sdma_init(&pdev->dev, spi_imx, master, res))
1190 		dev_err(&pdev->dev, "dma setup error,use pio instead\n");
1191 
1192 	spi_imx->devtype_data->reset(spi_imx);
1193 
1194 	spi_imx->devtype_data->intctrl(spi_imx, 0);
1195 
1196 	master->dev.of_node = pdev->dev.of_node;
1197 	ret = spi_bitbang_start(&spi_imx->bitbang);
1198 	if (ret) {
1199 		dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
1200 		goto out_clk_put;
1201 	}
1202 
1203 	dev_info(&pdev->dev, "probed\n");
1204 
1205 	clk_disable(spi_imx->clk_ipg);
1206 	clk_disable(spi_imx->clk_per);
1207 	return ret;
1208 
1209 out_clk_put:
1210 	clk_disable_unprepare(spi_imx->clk_ipg);
1211 out_put_per:
1212 	clk_disable_unprepare(spi_imx->clk_per);
1213 out_master_put:
1214 	spi_master_put(master);
1215 
1216 	return ret;
1217 }
1218 
spi_imx_remove(struct platform_device * pdev)1219 static int spi_imx_remove(struct platform_device *pdev)
1220 {
1221 	struct spi_master *master = platform_get_drvdata(pdev);
1222 	struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1223 	int ret;
1224 
1225 	spi_bitbang_stop(&spi_imx->bitbang);
1226 
1227 	ret = clk_enable(spi_imx->clk_per);
1228 	if (ret)
1229 		return ret;
1230 
1231 	ret = clk_enable(spi_imx->clk_ipg);
1232 	if (ret) {
1233 		clk_disable(spi_imx->clk_per);
1234 		return ret;
1235 	}
1236 
1237 	writel(0, spi_imx->base + MXC_CSPICTRL);
1238 	clk_disable_unprepare(spi_imx->clk_ipg);
1239 	clk_disable_unprepare(spi_imx->clk_per);
1240 	spi_imx_sdma_exit(spi_imx);
1241 	spi_master_put(master);
1242 
1243 	return 0;
1244 }
1245 
1246 static struct platform_driver spi_imx_driver = {
1247 	.driver = {
1248 		   .name = DRIVER_NAME,
1249 		   .owner = THIS_MODULE,
1250 		   .of_match_table = spi_imx_dt_ids,
1251 		   },
1252 	.id_table = spi_imx_devtype,
1253 	.probe = spi_imx_probe,
1254 	.remove = spi_imx_remove,
1255 };
1256 module_platform_driver(spi_imx_driver);
1257 
1258 MODULE_DESCRIPTION("SPI Master Controller driver");
1259 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1260 MODULE_LICENSE("GPL");
1261 MODULE_ALIAS("platform:" DRIVER_NAME);
1262