Loading...
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
55struct spi_imx_config {
56 unsigned int speed_hz;
57 unsigned int bpw;
58 unsigned int mode;
59 u8 cs;
60};
61
62enum 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
71struct spi_imx_data;
72
73struct 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
82struct 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
102static inline int is_imx27_cspi(struct spi_imx_data *d)
103{
104 return d->devtype_data->devtype == IMX27_CSPI;
105}
106
107static inline int is_imx35_cspi(struct spi_imx_data *d)
108{
109 return d->devtype_data->devtype == IMX35_CSPI;
110}
111
112static 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) \
118static 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) \
129static 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
143MXC_SPI_BUF_RX(u8)
144MXC_SPI_BUF_TX(u8)
145MXC_SPI_BUF_RX(u16)
146MXC_SPI_BUF_TX(u16)
147MXC_SPI_BUF_RX(u32)
148MXC_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 */
153static 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 */
157static 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 */
170static 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 */
207static 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
239static 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
252static 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
261static 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
300static 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
305static 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 */
335static 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
347static 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
356static 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
388static 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
393static 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
413static 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
425static 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
434static 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
459static 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
464static 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
480static 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
492static 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
501static 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
520static 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
525static void __maybe_unused mx1_reset(struct spi_imx_data *spi_imx)
526{
527 writel(1, spi_imx->base + MXC_RESET);
528}
529
530static 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
539static 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
548static 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
558static 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
567static 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
577static 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
586static 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
610static 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
620static 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
633static 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
645static 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
674static 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
710static 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
731static 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
747static void spi_imx_cleanup(struct spi_device *spi)
748{
749}
750
751static 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
874out_clk_put:
875 clk_disable(spi_imx->clk);
876 clk_put(spi_imx->clk);
877out_free_irq:
878 free_irq(spi_imx->irq, spi_imx);
879out_iounmap:
880 iounmap(spi_imx->base);
881out_release_mem:
882 release_mem_region(res->start, resource_size(res));
883out_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]);
887out_master_put:
888 spi_master_put(master);
889 kfree(master);
890 platform_set_drvdata(pdev, NULL);
891 return ret;
892}
893
894static 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
922static 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
933static int __init spi_imx_init(void)
934{
935 return platform_driver_register(&spi_imx_driver);
936}
937
938static void __exit spi_imx_exit(void)
939{
940 platform_driver_unregister(&spi_imx_driver);
941}
942
943module_init(spi_imx_init);
944module_exit(spi_imx_exit);
945
946MODULE_DESCRIPTION("SPI Master Controller driver");
947MODULE_AUTHOR("Sascha Hauer, Pengutronix");
948MODULE_LICENSE("GPL");
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)
59struct spi_imx_config {
60 unsigned int speed_hz;
61 unsigned int bpw;
62};
63
64enum spi_imx_devtype {
65 IMX1_CSPI,
66 IMX21_CSPI,
67 IMX27_CSPI,
68 IMX31_CSPI,
69 IMX35_CSPI, /* CSPI on all i.mx except above */
70 IMX51_ECSPI, /* ECSPI on i.mx51 and later */
71};
72
73struct spi_imx_data;
74
75struct spi_imx_devtype_data {
76 void (*intctrl)(struct spi_imx_data *, int);
77 int (*config)(struct spi_device *, struct spi_imx_config *);
78 void (*trigger)(struct spi_imx_data *);
79 int (*rx_available)(struct spi_imx_data *);
80 void (*reset)(struct spi_imx_data *);
81 enum spi_imx_devtype devtype;
82};
83
84struct spi_imx_data {
85 struct spi_bitbang bitbang;
86 struct device *dev;
87
88 struct completion xfer_done;
89 void __iomem *base;
90 unsigned long base_phys;
91
92 struct clk *clk_per;
93 struct clk *clk_ipg;
94 unsigned long spi_clk;
95 unsigned int spi_bus_clk;
96
97 unsigned int bytes_per_word;
98
99 unsigned int count;
100 void (*tx)(struct spi_imx_data *);
101 void (*rx)(struct spi_imx_data *);
102 void *rx_buf;
103 const void *tx_buf;
104 unsigned int txfifo; /* number of words pushed in tx FIFO */
105
106 /* DMA */
107 bool usedma;
108 u32 wml;
109 struct completion dma_rx_completion;
110 struct completion dma_tx_completion;
111
112 const struct spi_imx_devtype_data *devtype_data;
113};
114
115static inline int is_imx27_cspi(struct spi_imx_data *d)
116{
117 return d->devtype_data->devtype == IMX27_CSPI;
118}
119
120static inline int is_imx35_cspi(struct spi_imx_data *d)
121{
122 return d->devtype_data->devtype == IMX35_CSPI;
123}
124
125static inline int is_imx51_ecspi(struct spi_imx_data *d)
126{
127 return d->devtype_data->devtype == IMX51_ECSPI;
128}
129
130static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d)
131{
132 return is_imx51_ecspi(d) ? 64 : 8;
133}
134
135#define MXC_SPI_BUF_RX(type) \
136static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx) \
137{ \
138 unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA); \
139 \
140 if (spi_imx->rx_buf) { \
141 *(type *)spi_imx->rx_buf = val; \
142 spi_imx->rx_buf += sizeof(type); \
143 } \
144}
145
146#define MXC_SPI_BUF_TX(type) \
147static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx) \
148{ \
149 type val = 0; \
150 \
151 if (spi_imx->tx_buf) { \
152 val = *(type *)spi_imx->tx_buf; \
153 spi_imx->tx_buf += sizeof(type); \
154 } \
155 \
156 spi_imx->count -= sizeof(type); \
157 \
158 writel(val, spi_imx->base + MXC_CSPITXDATA); \
159}
160
161MXC_SPI_BUF_RX(u8)
162MXC_SPI_BUF_TX(u8)
163MXC_SPI_BUF_RX(u16)
164MXC_SPI_BUF_TX(u16)
165MXC_SPI_BUF_RX(u32)
166MXC_SPI_BUF_TX(u32)
167
168/* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
169 * (which is currently not the case in this driver)
170 */
171static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
172 256, 384, 512, 768, 1024};
173
174/* MX21, MX27 */
175static unsigned int spi_imx_clkdiv_1(unsigned int fin,
176 unsigned int fspi, unsigned int max, unsigned int *fres)
177{
178 int i;
179
180 for (i = 2; i < max; i++)
181 if (fspi * mxc_clkdivs[i] >= fin)
182 break;
183
184 *fres = fin / mxc_clkdivs[i];
185 return i;
186}
187
188/* MX1, MX31, MX35, MX51 CSPI */
189static unsigned int spi_imx_clkdiv_2(unsigned int fin,
190 unsigned int fspi, unsigned int *fres)
191{
192 int i, div = 4;
193
194 for (i = 0; i < 7; i++) {
195 if (fspi * div >= fin)
196 goto out;
197 div <<= 1;
198 }
199
200out:
201 *fres = fin / div;
202 return i;
203}
204
205static int spi_imx_bytes_per_word(const int bpw)
206{
207 return DIV_ROUND_UP(bpw, BITS_PER_BYTE);
208}
209
210static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
211 struct spi_transfer *transfer)
212{
213 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
214 unsigned int bpw;
215
216 if (!master->dma_rx)
217 return false;
218
219 if (!transfer)
220 return false;
221
222 bpw = transfer->bits_per_word;
223 if (!bpw)
224 bpw = spi->bits_per_word;
225
226 bpw = spi_imx_bytes_per_word(bpw);
227
228 if (bpw != 1 && bpw != 2 && bpw != 4)
229 return false;
230
231 if (transfer->len < spi_imx->wml * bpw)
232 return false;
233
234 if (transfer->len % (spi_imx->wml * bpw))
235 return false;
236
237 return true;
238}
239
240#define MX51_ECSPI_CTRL 0x08
241#define MX51_ECSPI_CTRL_ENABLE (1 << 0)
242#define MX51_ECSPI_CTRL_XCH (1 << 2)
243#define MX51_ECSPI_CTRL_SMC (1 << 3)
244#define MX51_ECSPI_CTRL_MODE_MASK (0xf << 4)
245#define MX51_ECSPI_CTRL_POSTDIV_OFFSET 8
246#define MX51_ECSPI_CTRL_PREDIV_OFFSET 12
247#define MX51_ECSPI_CTRL_CS(cs) ((cs) << 18)
248#define MX51_ECSPI_CTRL_BL_OFFSET 20
249
250#define MX51_ECSPI_CONFIG 0x0c
251#define MX51_ECSPI_CONFIG_SCLKPHA(cs) (1 << ((cs) + 0))
252#define MX51_ECSPI_CONFIG_SCLKPOL(cs) (1 << ((cs) + 4))
253#define MX51_ECSPI_CONFIG_SBBCTRL(cs) (1 << ((cs) + 8))
254#define MX51_ECSPI_CONFIG_SSBPOL(cs) (1 << ((cs) + 12))
255#define MX51_ECSPI_CONFIG_SCLKCTL(cs) (1 << ((cs) + 20))
256
257#define MX51_ECSPI_INT 0x10
258#define MX51_ECSPI_INT_TEEN (1 << 0)
259#define MX51_ECSPI_INT_RREN (1 << 3)
260
261#define MX51_ECSPI_DMA 0x14
262#define MX51_ECSPI_DMA_TX_WML(wml) ((wml) & 0x3f)
263#define MX51_ECSPI_DMA_RX_WML(wml) (((wml) & 0x3f) << 16)
264#define MX51_ECSPI_DMA_RXT_WML(wml) (((wml) & 0x3f) << 24)
265
266#define MX51_ECSPI_DMA_TEDEN (1 << 7)
267#define MX51_ECSPI_DMA_RXDEN (1 << 23)
268#define MX51_ECSPI_DMA_RXTDEN (1 << 31)
269
270#define MX51_ECSPI_STAT 0x18
271#define MX51_ECSPI_STAT_RR (1 << 3)
272
273#define MX51_ECSPI_TESTREG 0x20
274#define MX51_ECSPI_TESTREG_LBC BIT(31)
275
276/* MX51 eCSPI */
277static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
278 unsigned int fspi, unsigned int *fres)
279{
280 /*
281 * there are two 4-bit dividers, the pre-divider divides by
282 * $pre, the post-divider by 2^$post
283 */
284 unsigned int pre, post;
285 unsigned int fin = spi_imx->spi_clk;
286
287 if (unlikely(fspi > fin))
288 return 0;
289
290 post = fls(fin) - fls(fspi);
291 if (fin > fspi << post)
292 post++;
293
294 /* now we have: (fin <= fspi << post) with post being minimal */
295
296 post = max(4U, post) - 4;
297 if (unlikely(post > 0xf)) {
298 dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
299 fspi, fin);
300 return 0xff;
301 }
302
303 pre = DIV_ROUND_UP(fin, fspi << post) - 1;
304
305 dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
306 __func__, fin, fspi, post, pre);
307
308 /* Resulting frequency for the SCLK line. */
309 *fres = (fin / (pre + 1)) >> post;
310
311 return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
312 (post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
313}
314
315static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
316{
317 unsigned val = 0;
318
319 if (enable & MXC_INT_TE)
320 val |= MX51_ECSPI_INT_TEEN;
321
322 if (enable & MXC_INT_RR)
323 val |= MX51_ECSPI_INT_RREN;
324
325 writel(val, spi_imx->base + MX51_ECSPI_INT);
326}
327
328static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
329{
330 u32 reg;
331
332 reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
333 reg |= MX51_ECSPI_CTRL_XCH;
334 writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
335}
336
337static int mx51_ecspi_config(struct spi_device *spi,
338 struct spi_imx_config *config)
339{
340 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
341 u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
342 u32 clk = config->speed_hz, delay, reg;
343 u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
344
345 /*
346 * The hardware seems to have a race condition when changing modes. The
347 * current assumption is that the selection of the channel arrives
348 * earlier in the hardware than the mode bits when they are written at
349 * the same time.
350 * So set master mode for all channels as we do not support slave mode.
351 */
352 ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
353
354 /* set clock speed */
355 ctrl |= mx51_ecspi_clkdiv(spi_imx, config->speed_hz, &clk);
356 spi_imx->spi_bus_clk = clk;
357
358 /* set chip select to use */
359 ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
360
361 ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET;
362
363 cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
364
365 if (spi->mode & SPI_CPHA)
366 cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
367 else
368 cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
369
370 if (spi->mode & SPI_CPOL) {
371 cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
372 cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
373 } else {
374 cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
375 cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
376 }
377 if (spi->mode & SPI_CS_HIGH)
378 cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
379 else
380 cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
381
382 if (spi_imx->usedma)
383 ctrl |= MX51_ECSPI_CTRL_SMC;
384
385 /* CTRL register always go first to bring out controller from reset */
386 writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
387
388 reg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
389 if (spi->mode & SPI_LOOP)
390 reg |= MX51_ECSPI_TESTREG_LBC;
391 else
392 reg &= ~MX51_ECSPI_TESTREG_LBC;
393 writel(reg, spi_imx->base + MX51_ECSPI_TESTREG);
394
395 writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
396
397 /*
398 * Wait until the changes in the configuration register CONFIGREG
399 * propagate into the hardware. It takes exactly one tick of the
400 * SCLK clock, but we will wait two SCLK clock just to be sure. The
401 * effect of the delay it takes for the hardware to apply changes
402 * is noticable if the SCLK clock run very slow. In such a case, if
403 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
404 * be asserted before the SCLK polarity changes, which would disrupt
405 * the SPI communication as the device on the other end would consider
406 * the change of SCLK polarity as a clock tick already.
407 */
408 delay = (2 * 1000000) / clk;
409 if (likely(delay < 10)) /* SCLK is faster than 100 kHz */
410 udelay(delay);
411 else /* SCLK is _very_ slow */
412 usleep_range(delay, delay + 10);
413
414 /*
415 * Configure the DMA register: setup the watermark
416 * and enable DMA request.
417 */
418
419 writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml) |
420 MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
421 MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
422 MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
423 MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
424
425 return 0;
426}
427
428static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
429{
430 return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
431}
432
433static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
434{
435 /* drain receive buffer */
436 while (mx51_ecspi_rx_available(spi_imx))
437 readl(spi_imx->base + MXC_CSPIRXDATA);
438}
439
440#define MX31_INTREG_TEEN (1 << 0)
441#define MX31_INTREG_RREN (1 << 3)
442
443#define MX31_CSPICTRL_ENABLE (1 << 0)
444#define MX31_CSPICTRL_MASTER (1 << 1)
445#define MX31_CSPICTRL_XCH (1 << 2)
446#define MX31_CSPICTRL_SMC (1 << 3)
447#define MX31_CSPICTRL_POL (1 << 4)
448#define MX31_CSPICTRL_PHA (1 << 5)
449#define MX31_CSPICTRL_SSCTL (1 << 6)
450#define MX31_CSPICTRL_SSPOL (1 << 7)
451#define MX31_CSPICTRL_BC_SHIFT 8
452#define MX35_CSPICTRL_BL_SHIFT 20
453#define MX31_CSPICTRL_CS_SHIFT 24
454#define MX35_CSPICTRL_CS_SHIFT 12
455#define MX31_CSPICTRL_DR_SHIFT 16
456
457#define MX31_CSPI_DMAREG 0x10
458#define MX31_DMAREG_RH_DEN (1<<4)
459#define MX31_DMAREG_TH_DEN (1<<1)
460
461#define MX31_CSPISTATUS 0x14
462#define MX31_STATUS_RR (1 << 3)
463
464#define MX31_CSPI_TESTREG 0x1C
465#define MX31_TEST_LBC (1 << 14)
466
467/* These functions also work for the i.MX35, but be aware that
468 * the i.MX35 has a slightly different register layout for bits
469 * we do not use here.
470 */
471static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
472{
473 unsigned int val = 0;
474
475 if (enable & MXC_INT_TE)
476 val |= MX31_INTREG_TEEN;
477 if (enable & MXC_INT_RR)
478 val |= MX31_INTREG_RREN;
479
480 writel(val, spi_imx->base + MXC_CSPIINT);
481}
482
483static void mx31_trigger(struct spi_imx_data *spi_imx)
484{
485 unsigned int reg;
486
487 reg = readl(spi_imx->base + MXC_CSPICTRL);
488 reg |= MX31_CSPICTRL_XCH;
489 writel(reg, spi_imx->base + MXC_CSPICTRL);
490}
491
492static int mx31_config(struct spi_device *spi, struct spi_imx_config *config)
493{
494 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
495 unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
496 unsigned int clk;
497
498 reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz, &clk) <<
499 MX31_CSPICTRL_DR_SHIFT;
500 spi_imx->spi_bus_clk = clk;
501
502 if (is_imx35_cspi(spi_imx)) {
503 reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT;
504 reg |= MX31_CSPICTRL_SSCTL;
505 } else {
506 reg |= (config->bpw - 1) << MX31_CSPICTRL_BC_SHIFT;
507 }
508
509 if (spi->mode & SPI_CPHA)
510 reg |= MX31_CSPICTRL_PHA;
511 if (spi->mode & SPI_CPOL)
512 reg |= MX31_CSPICTRL_POL;
513 if (spi->mode & SPI_CS_HIGH)
514 reg |= MX31_CSPICTRL_SSPOL;
515 if (spi->cs_gpio < 0)
516 reg |= (spi->cs_gpio + 32) <<
517 (is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
518 MX31_CSPICTRL_CS_SHIFT);
519
520 if (spi_imx->usedma)
521 reg |= MX31_CSPICTRL_SMC;
522
523 writel(reg, spi_imx->base + MXC_CSPICTRL);
524
525 reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
526 if (spi->mode & SPI_LOOP)
527 reg |= MX31_TEST_LBC;
528 else
529 reg &= ~MX31_TEST_LBC;
530 writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
531
532 if (spi_imx->usedma) {
533 /* configure DMA requests when RXFIFO is half full and
534 when TXFIFO is half empty */
535 writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
536 spi_imx->base + MX31_CSPI_DMAREG);
537 }
538
539 return 0;
540}
541
542static int mx31_rx_available(struct spi_imx_data *spi_imx)
543{
544 return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
545}
546
547static void mx31_reset(struct spi_imx_data *spi_imx)
548{
549 /* drain receive buffer */
550 while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
551 readl(spi_imx->base + MXC_CSPIRXDATA);
552}
553
554#define MX21_INTREG_RR (1 << 4)
555#define MX21_INTREG_TEEN (1 << 9)
556#define MX21_INTREG_RREN (1 << 13)
557
558#define MX21_CSPICTRL_POL (1 << 5)
559#define MX21_CSPICTRL_PHA (1 << 6)
560#define MX21_CSPICTRL_SSPOL (1 << 8)
561#define MX21_CSPICTRL_XCH (1 << 9)
562#define MX21_CSPICTRL_ENABLE (1 << 10)
563#define MX21_CSPICTRL_MASTER (1 << 11)
564#define MX21_CSPICTRL_DR_SHIFT 14
565#define MX21_CSPICTRL_CS_SHIFT 19
566
567static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
568{
569 unsigned int val = 0;
570
571 if (enable & MXC_INT_TE)
572 val |= MX21_INTREG_TEEN;
573 if (enable & MXC_INT_RR)
574 val |= MX21_INTREG_RREN;
575
576 writel(val, spi_imx->base + MXC_CSPIINT);
577}
578
579static void mx21_trigger(struct spi_imx_data *spi_imx)
580{
581 unsigned int reg;
582
583 reg = readl(spi_imx->base + MXC_CSPICTRL);
584 reg |= MX21_CSPICTRL_XCH;
585 writel(reg, spi_imx->base + MXC_CSPICTRL);
586}
587
588static int mx21_config(struct spi_device *spi, struct spi_imx_config *config)
589{
590 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
591 unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
592 unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
593 unsigned int clk;
594
595 reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max, &clk)
596 << MX21_CSPICTRL_DR_SHIFT;
597 spi_imx->spi_bus_clk = clk;
598
599 reg |= config->bpw - 1;
600
601 if (spi->mode & SPI_CPHA)
602 reg |= MX21_CSPICTRL_PHA;
603 if (spi->mode & SPI_CPOL)
604 reg |= MX21_CSPICTRL_POL;
605 if (spi->mode & SPI_CS_HIGH)
606 reg |= MX21_CSPICTRL_SSPOL;
607 if (spi->cs_gpio < 0)
608 reg |= (spi->cs_gpio + 32) << MX21_CSPICTRL_CS_SHIFT;
609
610 writel(reg, spi_imx->base + MXC_CSPICTRL);
611
612 return 0;
613}
614
615static int mx21_rx_available(struct spi_imx_data *spi_imx)
616{
617 return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
618}
619
620static void mx21_reset(struct spi_imx_data *spi_imx)
621{
622 writel(1, spi_imx->base + MXC_RESET);
623}
624
625#define MX1_INTREG_RR (1 << 3)
626#define MX1_INTREG_TEEN (1 << 8)
627#define MX1_INTREG_RREN (1 << 11)
628
629#define MX1_CSPICTRL_POL (1 << 4)
630#define MX1_CSPICTRL_PHA (1 << 5)
631#define MX1_CSPICTRL_XCH (1 << 8)
632#define MX1_CSPICTRL_ENABLE (1 << 9)
633#define MX1_CSPICTRL_MASTER (1 << 10)
634#define MX1_CSPICTRL_DR_SHIFT 13
635
636static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
637{
638 unsigned int val = 0;
639
640 if (enable & MXC_INT_TE)
641 val |= MX1_INTREG_TEEN;
642 if (enable & MXC_INT_RR)
643 val |= MX1_INTREG_RREN;
644
645 writel(val, spi_imx->base + MXC_CSPIINT);
646}
647
648static void mx1_trigger(struct spi_imx_data *spi_imx)
649{
650 unsigned int reg;
651
652 reg = readl(spi_imx->base + MXC_CSPICTRL);
653 reg |= MX1_CSPICTRL_XCH;
654 writel(reg, spi_imx->base + MXC_CSPICTRL);
655}
656
657static int mx1_config(struct spi_device *spi, struct spi_imx_config *config)
658{
659 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
660 unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
661 unsigned int clk;
662
663 reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz, &clk) <<
664 MX1_CSPICTRL_DR_SHIFT;
665 spi_imx->spi_bus_clk = clk;
666
667 reg |= config->bpw - 1;
668
669 if (spi->mode & SPI_CPHA)
670 reg |= MX1_CSPICTRL_PHA;
671 if (spi->mode & SPI_CPOL)
672 reg |= MX1_CSPICTRL_POL;
673
674 writel(reg, spi_imx->base + MXC_CSPICTRL);
675
676 return 0;
677}
678
679static int mx1_rx_available(struct spi_imx_data *spi_imx)
680{
681 return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
682}
683
684static void mx1_reset(struct spi_imx_data *spi_imx)
685{
686 writel(1, spi_imx->base + MXC_RESET);
687}
688
689static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
690 .intctrl = mx1_intctrl,
691 .config = mx1_config,
692 .trigger = mx1_trigger,
693 .rx_available = mx1_rx_available,
694 .reset = mx1_reset,
695 .devtype = IMX1_CSPI,
696};
697
698static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
699 .intctrl = mx21_intctrl,
700 .config = mx21_config,
701 .trigger = mx21_trigger,
702 .rx_available = mx21_rx_available,
703 .reset = mx21_reset,
704 .devtype = IMX21_CSPI,
705};
706
707static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
708 /* i.mx27 cspi shares the functions with i.mx21 one */
709 .intctrl = mx21_intctrl,
710 .config = mx21_config,
711 .trigger = mx21_trigger,
712 .rx_available = mx21_rx_available,
713 .reset = mx21_reset,
714 .devtype = IMX27_CSPI,
715};
716
717static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
718 .intctrl = mx31_intctrl,
719 .config = mx31_config,
720 .trigger = mx31_trigger,
721 .rx_available = mx31_rx_available,
722 .reset = mx31_reset,
723 .devtype = IMX31_CSPI,
724};
725
726static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
727 /* i.mx35 and later cspi shares the functions with i.mx31 one */
728 .intctrl = mx31_intctrl,
729 .config = mx31_config,
730 .trigger = mx31_trigger,
731 .rx_available = mx31_rx_available,
732 .reset = mx31_reset,
733 .devtype = IMX35_CSPI,
734};
735
736static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
737 .intctrl = mx51_ecspi_intctrl,
738 .config = mx51_ecspi_config,
739 .trigger = mx51_ecspi_trigger,
740 .rx_available = mx51_ecspi_rx_available,
741 .reset = mx51_ecspi_reset,
742 .devtype = IMX51_ECSPI,
743};
744
745static const struct platform_device_id spi_imx_devtype[] = {
746 {
747 .name = "imx1-cspi",
748 .driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
749 }, {
750 .name = "imx21-cspi",
751 .driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
752 }, {
753 .name = "imx27-cspi",
754 .driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
755 }, {
756 .name = "imx31-cspi",
757 .driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
758 }, {
759 .name = "imx35-cspi",
760 .driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
761 }, {
762 .name = "imx51-ecspi",
763 .driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
764 }, {
765 /* sentinel */
766 }
767};
768
769static const struct of_device_id spi_imx_dt_ids[] = {
770 { .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
771 { .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
772 { .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
773 { .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
774 { .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
775 { .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
776 { /* sentinel */ }
777};
778MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
779
780static void spi_imx_chipselect(struct spi_device *spi, int is_active)
781{
782 int active = is_active != BITBANG_CS_INACTIVE;
783 int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
784
785 if (!gpio_is_valid(spi->cs_gpio))
786 return;
787
788 gpio_set_value(spi->cs_gpio, dev_is_lowactive ^ active);
789}
790
791static void spi_imx_push(struct spi_imx_data *spi_imx)
792{
793 while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) {
794 if (!spi_imx->count)
795 break;
796 spi_imx->tx(spi_imx);
797 spi_imx->txfifo++;
798 }
799
800 spi_imx->devtype_data->trigger(spi_imx);
801}
802
803static irqreturn_t spi_imx_isr(int irq, void *dev_id)
804{
805 struct spi_imx_data *spi_imx = dev_id;
806
807 while (spi_imx->devtype_data->rx_available(spi_imx)) {
808 spi_imx->rx(spi_imx);
809 spi_imx->txfifo--;
810 }
811
812 if (spi_imx->count) {
813 spi_imx_push(spi_imx);
814 return IRQ_HANDLED;
815 }
816
817 if (spi_imx->txfifo) {
818 /* No data left to push, but still waiting for rx data,
819 * enable receive data available interrupt.
820 */
821 spi_imx->devtype_data->intctrl(
822 spi_imx, MXC_INT_RR);
823 return IRQ_HANDLED;
824 }
825
826 spi_imx->devtype_data->intctrl(spi_imx, 0);
827 complete(&spi_imx->xfer_done);
828
829 return IRQ_HANDLED;
830}
831
832static int spi_imx_dma_configure(struct spi_master *master,
833 int bytes_per_word)
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 if (bytes_per_word == spi_imx->bytes_per_word)
841 /* Same as last time */
842 return 0;
843
844 switch (bytes_per_word) {
845 case 4:
846 buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
847 break;
848 case 2:
849 buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
850 break;
851 case 1:
852 buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
853 break;
854 default:
855 return -EINVAL;
856 }
857
858 tx.direction = DMA_MEM_TO_DEV;
859 tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
860 tx.dst_addr_width = buswidth;
861 tx.dst_maxburst = spi_imx->wml;
862 ret = dmaengine_slave_config(master->dma_tx, &tx);
863 if (ret) {
864 dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
865 return ret;
866 }
867
868 rx.direction = DMA_DEV_TO_MEM;
869 rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
870 rx.src_addr_width = buswidth;
871 rx.src_maxburst = spi_imx->wml;
872 ret = dmaengine_slave_config(master->dma_rx, &rx);
873 if (ret) {
874 dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
875 return ret;
876 }
877
878 spi_imx->bytes_per_word = bytes_per_word;
879
880 return 0;
881}
882
883static int spi_imx_setupxfer(struct spi_device *spi,
884 struct spi_transfer *t)
885{
886 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
887 struct spi_imx_config config;
888 int ret;
889
890 config.bpw = t ? t->bits_per_word : spi->bits_per_word;
891 config.speed_hz = t ? t->speed_hz : spi->max_speed_hz;
892
893 if (!config.speed_hz)
894 config.speed_hz = spi->max_speed_hz;
895 if (!config.bpw)
896 config.bpw = spi->bits_per_word;
897
898 /* Initialize the functions for transfer */
899 if (config.bpw <= 8) {
900 spi_imx->rx = spi_imx_buf_rx_u8;
901 spi_imx->tx = spi_imx_buf_tx_u8;
902 } else if (config.bpw <= 16) {
903 spi_imx->rx = spi_imx_buf_rx_u16;
904 spi_imx->tx = spi_imx_buf_tx_u16;
905 } else {
906 spi_imx->rx = spi_imx_buf_rx_u32;
907 spi_imx->tx = spi_imx_buf_tx_u32;
908 }
909
910 if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
911 spi_imx->usedma = 1;
912 else
913 spi_imx->usedma = 0;
914
915 if (spi_imx->usedma) {
916 ret = spi_imx_dma_configure(spi->master,
917 spi_imx_bytes_per_word(config.bpw));
918 if (ret)
919 return ret;
920 }
921
922 spi_imx->devtype_data->config(spi, &config);
923
924 return 0;
925}
926
927static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
928{
929 struct spi_master *master = spi_imx->bitbang.master;
930
931 if (master->dma_rx) {
932 dma_release_channel(master->dma_rx);
933 master->dma_rx = NULL;
934 }
935
936 if (master->dma_tx) {
937 dma_release_channel(master->dma_tx);
938 master->dma_tx = NULL;
939 }
940}
941
942static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
943 struct spi_master *master)
944{
945 int ret;
946
947 /* use pio mode for i.mx6dl chip TKT238285 */
948 if (of_machine_is_compatible("fsl,imx6dl"))
949 return 0;
950
951 spi_imx->wml = spi_imx_get_fifosize(spi_imx) / 2;
952
953 /* Prepare for TX DMA: */
954 master->dma_tx = dma_request_slave_channel_reason(dev, "tx");
955 if (IS_ERR(master->dma_tx)) {
956 ret = PTR_ERR(master->dma_tx);
957 dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
958 master->dma_tx = NULL;
959 goto err;
960 }
961
962 /* Prepare for RX : */
963 master->dma_rx = dma_request_slave_channel_reason(dev, "rx");
964 if (IS_ERR(master->dma_rx)) {
965 ret = PTR_ERR(master->dma_rx);
966 dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
967 master->dma_rx = NULL;
968 goto err;
969 }
970
971 spi_imx_dma_configure(master, 1);
972
973 init_completion(&spi_imx->dma_rx_completion);
974 init_completion(&spi_imx->dma_tx_completion);
975 master->can_dma = spi_imx_can_dma;
976 master->max_dma_len = MAX_SDMA_BD_BYTES;
977 spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
978 SPI_MASTER_MUST_TX;
979
980 return 0;
981err:
982 spi_imx_sdma_exit(spi_imx);
983 return ret;
984}
985
986static void spi_imx_dma_rx_callback(void *cookie)
987{
988 struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
989
990 complete(&spi_imx->dma_rx_completion);
991}
992
993static void spi_imx_dma_tx_callback(void *cookie)
994{
995 struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
996
997 complete(&spi_imx->dma_tx_completion);
998}
999
1000static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1001{
1002 unsigned long timeout = 0;
1003
1004 /* Time with actual data transfer and CS change delay related to HW */
1005 timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1006
1007 /* Add extra second for scheduler related activities */
1008 timeout += 1;
1009
1010 /* Double calculated timeout */
1011 return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1012}
1013
1014static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1015 struct spi_transfer *transfer)
1016{
1017 struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1018 unsigned long transfer_timeout;
1019 unsigned long timeout;
1020 struct spi_master *master = spi_imx->bitbang.master;
1021 struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1022
1023 /*
1024 * The TX DMA setup starts the transfer, so make sure RX is configured
1025 * before TX.
1026 */
1027 desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
1028 rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1029 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1030 if (!desc_rx)
1031 return -EINVAL;
1032
1033 desc_rx->callback = spi_imx_dma_rx_callback;
1034 desc_rx->callback_param = (void *)spi_imx;
1035 dmaengine_submit(desc_rx);
1036 reinit_completion(&spi_imx->dma_rx_completion);
1037 dma_async_issue_pending(master->dma_rx);
1038
1039 desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
1040 tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1041 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1042 if (!desc_tx) {
1043 dmaengine_terminate_all(master->dma_tx);
1044 return -EINVAL;
1045 }
1046
1047 desc_tx->callback = spi_imx_dma_tx_callback;
1048 desc_tx->callback_param = (void *)spi_imx;
1049 dmaengine_submit(desc_tx);
1050 reinit_completion(&spi_imx->dma_tx_completion);
1051 dma_async_issue_pending(master->dma_tx);
1052
1053 transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1054
1055 /* Wait SDMA to finish the data transfer.*/
1056 timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1057 transfer_timeout);
1058 if (!timeout) {
1059 dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1060 dmaengine_terminate_all(master->dma_tx);
1061 dmaengine_terminate_all(master->dma_rx);
1062 return -ETIMEDOUT;
1063 }
1064
1065 timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1066 transfer_timeout);
1067 if (!timeout) {
1068 dev_err(&master->dev, "I/O Error in DMA RX\n");
1069 spi_imx->devtype_data->reset(spi_imx);
1070 dmaengine_terminate_all(master->dma_rx);
1071 return -ETIMEDOUT;
1072 }
1073
1074 return transfer->len;
1075}
1076
1077static int spi_imx_pio_transfer(struct spi_device *spi,
1078 struct spi_transfer *transfer)
1079{
1080 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1081 unsigned long transfer_timeout;
1082 unsigned long timeout;
1083
1084 spi_imx->tx_buf = transfer->tx_buf;
1085 spi_imx->rx_buf = transfer->rx_buf;
1086 spi_imx->count = transfer->len;
1087 spi_imx->txfifo = 0;
1088
1089 reinit_completion(&spi_imx->xfer_done);
1090
1091 spi_imx_push(spi_imx);
1092
1093 spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1094
1095 transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1096
1097 timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
1098 transfer_timeout);
1099 if (!timeout) {
1100 dev_err(&spi->dev, "I/O Error in PIO\n");
1101 spi_imx->devtype_data->reset(spi_imx);
1102 return -ETIMEDOUT;
1103 }
1104
1105 return transfer->len;
1106}
1107
1108static int spi_imx_transfer(struct spi_device *spi,
1109 struct spi_transfer *transfer)
1110{
1111 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1112
1113 if (spi_imx->usedma)
1114 return spi_imx_dma_transfer(spi_imx, transfer);
1115 else
1116 return spi_imx_pio_transfer(spi, transfer);
1117}
1118
1119static int spi_imx_setup(struct spi_device *spi)
1120{
1121 dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1122 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1123
1124 if (gpio_is_valid(spi->cs_gpio))
1125 gpio_direction_output(spi->cs_gpio,
1126 spi->mode & SPI_CS_HIGH ? 0 : 1);
1127
1128 spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
1129
1130 return 0;
1131}
1132
1133static void spi_imx_cleanup(struct spi_device *spi)
1134{
1135}
1136
1137static int
1138spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1139{
1140 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1141 int ret;
1142
1143 ret = clk_enable(spi_imx->clk_per);
1144 if (ret)
1145 return ret;
1146
1147 ret = clk_enable(spi_imx->clk_ipg);
1148 if (ret) {
1149 clk_disable(spi_imx->clk_per);
1150 return ret;
1151 }
1152
1153 return 0;
1154}
1155
1156static int
1157spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1158{
1159 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1160
1161 clk_disable(spi_imx->clk_ipg);
1162 clk_disable(spi_imx->clk_per);
1163 return 0;
1164}
1165
1166static int spi_imx_probe(struct platform_device *pdev)
1167{
1168 struct device_node *np = pdev->dev.of_node;
1169 const struct of_device_id *of_id =
1170 of_match_device(spi_imx_dt_ids, &pdev->dev);
1171 struct spi_imx_master *mxc_platform_info =
1172 dev_get_platdata(&pdev->dev);
1173 struct spi_master *master;
1174 struct spi_imx_data *spi_imx;
1175 struct resource *res;
1176 int i, ret, irq;
1177
1178 if (!np && !mxc_platform_info) {
1179 dev_err(&pdev->dev, "can't get the platform data\n");
1180 return -EINVAL;
1181 }
1182
1183 master = spi_alloc_master(&pdev->dev, sizeof(struct spi_imx_data));
1184 if (!master)
1185 return -ENOMEM;
1186
1187 platform_set_drvdata(pdev, master);
1188
1189 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1190 master->bus_num = np ? -1 : pdev->id;
1191
1192 spi_imx = spi_master_get_devdata(master);
1193 spi_imx->bitbang.master = master;
1194 spi_imx->dev = &pdev->dev;
1195
1196 spi_imx->devtype_data = of_id ? of_id->data :
1197 (struct spi_imx_devtype_data *)pdev->id_entry->driver_data;
1198
1199 if (mxc_platform_info) {
1200 master->num_chipselect = mxc_platform_info->num_chipselect;
1201 master->cs_gpios = devm_kzalloc(&master->dev,
1202 sizeof(int) * master->num_chipselect, GFP_KERNEL);
1203 if (!master->cs_gpios)
1204 return -ENOMEM;
1205
1206 for (i = 0; i < master->num_chipselect; i++)
1207 master->cs_gpios[i] = mxc_platform_info->chipselect[i];
1208 }
1209
1210 spi_imx->bitbang.chipselect = spi_imx_chipselect;
1211 spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1212 spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1213 spi_imx->bitbang.master->setup = spi_imx_setup;
1214 spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1215 spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1216 spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1217 spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1218 if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx))
1219 spi_imx->bitbang.master->mode_bits |= SPI_LOOP;
1220
1221 init_completion(&spi_imx->xfer_done);
1222
1223 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1224 spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1225 if (IS_ERR(spi_imx->base)) {
1226 ret = PTR_ERR(spi_imx->base);
1227 goto out_master_put;
1228 }
1229 spi_imx->base_phys = res->start;
1230
1231 irq = platform_get_irq(pdev, 0);
1232 if (irq < 0) {
1233 ret = irq;
1234 goto out_master_put;
1235 }
1236
1237 ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1238 dev_name(&pdev->dev), spi_imx);
1239 if (ret) {
1240 dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1241 goto out_master_put;
1242 }
1243
1244 spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1245 if (IS_ERR(spi_imx->clk_ipg)) {
1246 ret = PTR_ERR(spi_imx->clk_ipg);
1247 goto out_master_put;
1248 }
1249
1250 spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1251 if (IS_ERR(spi_imx->clk_per)) {
1252 ret = PTR_ERR(spi_imx->clk_per);
1253 goto out_master_put;
1254 }
1255
1256 ret = clk_prepare_enable(spi_imx->clk_per);
1257 if (ret)
1258 goto out_master_put;
1259
1260 ret = clk_prepare_enable(spi_imx->clk_ipg);
1261 if (ret)
1262 goto out_put_per;
1263
1264 spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1265 /*
1266 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1267 * if validated on other chips.
1268 */
1269 if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx)) {
1270 ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
1271 if (ret == -EPROBE_DEFER)
1272 goto out_clk_put;
1273
1274 if (ret < 0)
1275 dev_err(&pdev->dev, "dma setup error %d, use pio\n",
1276 ret);
1277 }
1278
1279 spi_imx->devtype_data->reset(spi_imx);
1280
1281 spi_imx->devtype_data->intctrl(spi_imx, 0);
1282
1283 master->dev.of_node = pdev->dev.of_node;
1284 ret = spi_bitbang_start(&spi_imx->bitbang);
1285 if (ret) {
1286 dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
1287 goto out_clk_put;
1288 }
1289
1290 if (!master->cs_gpios) {
1291 dev_err(&pdev->dev, "No CS GPIOs available\n");
1292 ret = -EINVAL;
1293 goto out_clk_put;
1294 }
1295
1296 for (i = 0; i < master->num_chipselect; i++) {
1297 if (!gpio_is_valid(master->cs_gpios[i]))
1298 continue;
1299
1300 ret = devm_gpio_request(&pdev->dev, master->cs_gpios[i],
1301 DRIVER_NAME);
1302 if (ret) {
1303 dev_err(&pdev->dev, "Can't get CS GPIO %i\n",
1304 master->cs_gpios[i]);
1305 goto out_clk_put;
1306 }
1307 }
1308
1309 dev_info(&pdev->dev, "probed\n");
1310
1311 clk_disable(spi_imx->clk_ipg);
1312 clk_disable(spi_imx->clk_per);
1313 return ret;
1314
1315out_clk_put:
1316 clk_disable_unprepare(spi_imx->clk_ipg);
1317out_put_per:
1318 clk_disable_unprepare(spi_imx->clk_per);
1319out_master_put:
1320 spi_master_put(master);
1321
1322 return ret;
1323}
1324
1325static int spi_imx_remove(struct platform_device *pdev)
1326{
1327 struct spi_master *master = platform_get_drvdata(pdev);
1328 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1329
1330 spi_bitbang_stop(&spi_imx->bitbang);
1331
1332 writel(0, spi_imx->base + MXC_CSPICTRL);
1333 clk_unprepare(spi_imx->clk_ipg);
1334 clk_unprepare(spi_imx->clk_per);
1335 spi_imx_sdma_exit(spi_imx);
1336 spi_master_put(master);
1337
1338 return 0;
1339}
1340
1341static struct platform_driver spi_imx_driver = {
1342 .driver = {
1343 .name = DRIVER_NAME,
1344 .of_match_table = spi_imx_dt_ids,
1345 },
1346 .id_table = spi_imx_devtype,
1347 .probe = spi_imx_probe,
1348 .remove = spi_imx_remove,
1349};
1350module_platform_driver(spi_imx_driver);
1351
1352MODULE_DESCRIPTION("SPI Master Controller driver");
1353MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1354MODULE_LICENSE("GPL");
1355MODULE_ALIAS("platform:" DRIVER_NAME);