1 // SPDX-License-Identifier: GPL-2.0+
2 // Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
3 // Copyright (C) 2008 Juergen Beisert
4
5 #include <linux/clk.h>
6 #include <linux/completion.h>
7 #include <linux/delay.h>
8 #include <linux/dmaengine.h>
9 #include <linux/dma-mapping.h>
10 #include <linux/err.h>
11 #include <linux/gpio.h>
12 #include <linux/interrupt.h>
13 #include <linux/io.h>
14 #include <linux/irq.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/platform_device.h>
18 #include <linux/slab.h>
19 #include <linux/spi/spi.h>
20 #include <linux/spi/spi_bitbang.h>
21 #include <linux/types.h>
22 #include <linux/of.h>
23 #include <linux/of_device.h>
24 #include <linux/of_gpio.h>
25
26 #include <linux/platform_data/dma-imx.h>
27 #include <linux/platform_data/spi-imx.h>
28
29 #define DRIVER_NAME "spi_imx"
30
31 static bool use_dma = true;
32 module_param(use_dma, bool, 0644);
33 MODULE_PARM_DESC(use_dma, "Enable usage of DMA when available (default)");
34
35 #define MXC_CSPIRXDATA 0x00
36 #define MXC_CSPITXDATA 0x04
37 #define MXC_CSPICTRL 0x08
38 #define MXC_CSPIINT 0x0c
39 #define MXC_RESET 0x1c
40
41 /* generic defines to abstract from the different register layouts */
42 #define MXC_INT_RR (1 << 0) /* Receive data ready interrupt */
43 #define MXC_INT_TE (1 << 1) /* Transmit FIFO empty interrupt */
44 #define MXC_INT_RDR BIT(4) /* Receive date threshold interrupt */
45
46 /* The maximum bytes that a sdma BD can transfer. */
47 #define MAX_SDMA_BD_BYTES (1 << 15)
48 #define MX51_ECSPI_CTRL_MAX_BURST 512
49 /* The maximum bytes that IMX53_ECSPI can transfer in slave mode.*/
50 #define MX53_MAX_TRANSFER_BYTES 512
51
52 enum spi_imx_devtype {
53 IMX1_CSPI,
54 IMX21_CSPI,
55 IMX27_CSPI,
56 IMX31_CSPI,
57 IMX35_CSPI, /* CSPI on all i.mx except above */
58 IMX51_ECSPI, /* ECSPI on i.mx51 */
59 IMX53_ECSPI, /* ECSPI on i.mx53 and later */
60 };
61
62 struct spi_imx_data;
63
64 struct spi_imx_devtype_data {
65 void (*intctrl)(struct spi_imx_data *, int);
66 int (*prepare_message)(struct spi_imx_data *, struct spi_message *);
67 int (*prepare_transfer)(struct spi_imx_data *, struct spi_device *,
68 struct spi_transfer *);
69 void (*trigger)(struct spi_imx_data *);
70 int (*rx_available)(struct spi_imx_data *);
71 void (*reset)(struct spi_imx_data *);
72 void (*setup_wml)(struct spi_imx_data *);
73 void (*disable)(struct spi_imx_data *);
74 bool has_dmamode;
75 bool has_slavemode;
76 unsigned int fifo_size;
77 bool dynamic_burst;
78 enum spi_imx_devtype devtype;
79 };
80
81 struct spi_imx_data {
82 struct spi_bitbang bitbang;
83 struct device *dev;
84
85 struct completion xfer_done;
86 void __iomem *base;
87 unsigned long base_phys;
88
89 struct clk *clk_per;
90 struct clk *clk_ipg;
91 unsigned long spi_clk;
92 unsigned int spi_bus_clk;
93
94 unsigned int bits_per_word;
95 unsigned int spi_drctl;
96
97 unsigned int count, remainder;
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 unsigned int dynamic_burst;
104
105 /* Slave mode */
106 bool slave_mode;
107 bool slave_aborted;
108 unsigned int slave_burst;
109
110 /* DMA */
111 bool usedma;
112 u32 wml;
113 struct completion dma_rx_completion;
114 struct completion dma_tx_completion;
115
116 const struct spi_imx_devtype_data *devtype_data;
117 };
118
is_imx27_cspi(struct spi_imx_data * d)119 static inline int is_imx27_cspi(struct spi_imx_data *d)
120 {
121 return d->devtype_data->devtype == IMX27_CSPI;
122 }
123
is_imx35_cspi(struct spi_imx_data * d)124 static inline int is_imx35_cspi(struct spi_imx_data *d)
125 {
126 return d->devtype_data->devtype == IMX35_CSPI;
127 }
128
is_imx51_ecspi(struct spi_imx_data * d)129 static inline int is_imx51_ecspi(struct spi_imx_data *d)
130 {
131 return d->devtype_data->devtype == IMX51_ECSPI;
132 }
133
is_imx53_ecspi(struct spi_imx_data * d)134 static inline int is_imx53_ecspi(struct spi_imx_data *d)
135 {
136 return d->devtype_data->devtype == IMX53_ECSPI;
137 }
138
139 #define MXC_SPI_BUF_RX(type) \
140 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx) \
141 { \
142 unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA); \
143 \
144 if (spi_imx->rx_buf) { \
145 *(type *)spi_imx->rx_buf = val; \
146 spi_imx->rx_buf += sizeof(type); \
147 } \
148 \
149 spi_imx->remainder -= sizeof(type); \
150 }
151
152 #define MXC_SPI_BUF_TX(type) \
153 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx) \
154 { \
155 type val = 0; \
156 \
157 if (spi_imx->tx_buf) { \
158 val = *(type *)spi_imx->tx_buf; \
159 spi_imx->tx_buf += sizeof(type); \
160 } \
161 \
162 spi_imx->count -= sizeof(type); \
163 \
164 writel(val, spi_imx->base + MXC_CSPITXDATA); \
165 }
166
167 MXC_SPI_BUF_RX(u8)
168 MXC_SPI_BUF_TX(u8)
169 MXC_SPI_BUF_RX(u16)
170 MXC_SPI_BUF_TX(u16)
171 MXC_SPI_BUF_RX(u32)
172 MXC_SPI_BUF_TX(u32)
173
174 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
175 * (which is currently not the case in this driver)
176 */
177 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
178 256, 384, 512, 768, 1024};
179
180 /* MX21, MX27 */
spi_imx_clkdiv_1(unsigned int fin,unsigned int fspi,unsigned int max,unsigned int * fres)181 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
182 unsigned int fspi, unsigned int max, unsigned int *fres)
183 {
184 int i;
185
186 for (i = 2; i < max; i++)
187 if (fspi * mxc_clkdivs[i] >= fin)
188 break;
189
190 *fres = fin / mxc_clkdivs[i];
191 return i;
192 }
193
194 /* MX1, MX31, MX35, MX51 CSPI */
spi_imx_clkdiv_2(unsigned int fin,unsigned int fspi,unsigned int * fres)195 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
196 unsigned int fspi, unsigned int *fres)
197 {
198 int i, div = 4;
199
200 for (i = 0; i < 7; i++) {
201 if (fspi * div >= fin)
202 goto out;
203 div <<= 1;
204 }
205
206 out:
207 *fres = fin / div;
208 return i;
209 }
210
spi_imx_bytes_per_word(const int bits_per_word)211 static int spi_imx_bytes_per_word(const int bits_per_word)
212 {
213 if (bits_per_word <= 8)
214 return 1;
215 else if (bits_per_word <= 16)
216 return 2;
217 else
218 return 4;
219 }
220
spi_imx_can_dma(struct spi_master * master,struct spi_device * spi,struct spi_transfer * transfer)221 static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
222 struct spi_transfer *transfer)
223 {
224 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
225
226 if (!use_dma)
227 return false;
228
229 if (!master->dma_rx)
230 return false;
231
232 if (spi_imx->slave_mode)
233 return false;
234
235 if (transfer->len < spi_imx->devtype_data->fifo_size)
236 return false;
237
238 spi_imx->dynamic_burst = 0;
239
240 return true;
241 }
242
243 #define MX51_ECSPI_CTRL 0x08
244 #define MX51_ECSPI_CTRL_ENABLE (1 << 0)
245 #define MX51_ECSPI_CTRL_XCH (1 << 2)
246 #define MX51_ECSPI_CTRL_SMC (1 << 3)
247 #define MX51_ECSPI_CTRL_MODE_MASK (0xf << 4)
248 #define MX51_ECSPI_CTRL_DRCTL(drctl) ((drctl) << 16)
249 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET 8
250 #define MX51_ECSPI_CTRL_PREDIV_OFFSET 12
251 #define MX51_ECSPI_CTRL_CS(cs) ((cs) << 18)
252 #define MX51_ECSPI_CTRL_BL_OFFSET 20
253 #define MX51_ECSPI_CTRL_BL_MASK (0xfff << 20)
254
255 #define MX51_ECSPI_CONFIG 0x0c
256 #define MX51_ECSPI_CONFIG_SCLKPHA(cs) (1 << ((cs) + 0))
257 #define MX51_ECSPI_CONFIG_SCLKPOL(cs) (1 << ((cs) + 4))
258 #define MX51_ECSPI_CONFIG_SBBCTRL(cs) (1 << ((cs) + 8))
259 #define MX51_ECSPI_CONFIG_SSBPOL(cs) (1 << ((cs) + 12))
260 #define MX51_ECSPI_CONFIG_SCLKCTL(cs) (1 << ((cs) + 20))
261
262 #define MX51_ECSPI_INT 0x10
263 #define MX51_ECSPI_INT_TEEN (1 << 0)
264 #define MX51_ECSPI_INT_RREN (1 << 3)
265 #define MX51_ECSPI_INT_RDREN (1 << 4)
266
267 #define MX51_ECSPI_DMA 0x14
268 #define MX51_ECSPI_DMA_TX_WML(wml) ((wml) & 0x3f)
269 #define MX51_ECSPI_DMA_RX_WML(wml) (((wml) & 0x3f) << 16)
270 #define MX51_ECSPI_DMA_RXT_WML(wml) (((wml) & 0x3f) << 24)
271
272 #define MX51_ECSPI_DMA_TEDEN (1 << 7)
273 #define MX51_ECSPI_DMA_RXDEN (1 << 23)
274 #define MX51_ECSPI_DMA_RXTDEN (1 << 31)
275
276 #define MX51_ECSPI_STAT 0x18
277 #define MX51_ECSPI_STAT_RR (1 << 3)
278
279 #define MX51_ECSPI_TESTREG 0x20
280 #define MX51_ECSPI_TESTREG_LBC BIT(31)
281
spi_imx_buf_rx_swap_u32(struct spi_imx_data * spi_imx)282 static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
283 {
284 unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
285 #ifdef __LITTLE_ENDIAN
286 unsigned int bytes_per_word;
287 #endif
288
289 if (spi_imx->rx_buf) {
290 #ifdef __LITTLE_ENDIAN
291 bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
292 if (bytes_per_word == 1)
293 val = cpu_to_be32(val);
294 else if (bytes_per_word == 2)
295 val = (val << 16) | (val >> 16);
296 #endif
297 *(u32 *)spi_imx->rx_buf = val;
298 spi_imx->rx_buf += sizeof(u32);
299 }
300
301 spi_imx->remainder -= sizeof(u32);
302 }
303
spi_imx_buf_rx_swap(struct spi_imx_data * spi_imx)304 static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
305 {
306 int unaligned;
307 u32 val;
308
309 unaligned = spi_imx->remainder % 4;
310
311 if (!unaligned) {
312 spi_imx_buf_rx_swap_u32(spi_imx);
313 return;
314 }
315
316 if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
317 spi_imx_buf_rx_u16(spi_imx);
318 return;
319 }
320
321 val = readl(spi_imx->base + MXC_CSPIRXDATA);
322
323 while (unaligned--) {
324 if (spi_imx->rx_buf) {
325 *(u8 *)spi_imx->rx_buf = (val >> (8 * unaligned)) & 0xff;
326 spi_imx->rx_buf++;
327 }
328 spi_imx->remainder--;
329 }
330 }
331
spi_imx_buf_tx_swap_u32(struct spi_imx_data * spi_imx)332 static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
333 {
334 u32 val = 0;
335 #ifdef __LITTLE_ENDIAN
336 unsigned int bytes_per_word;
337 #endif
338
339 if (spi_imx->tx_buf) {
340 val = *(u32 *)spi_imx->tx_buf;
341 spi_imx->tx_buf += sizeof(u32);
342 }
343
344 spi_imx->count -= sizeof(u32);
345 #ifdef __LITTLE_ENDIAN
346 bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
347
348 if (bytes_per_word == 1)
349 val = cpu_to_be32(val);
350 else if (bytes_per_word == 2)
351 val = (val << 16) | (val >> 16);
352 #endif
353 writel(val, spi_imx->base + MXC_CSPITXDATA);
354 }
355
spi_imx_buf_tx_swap(struct spi_imx_data * spi_imx)356 static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
357 {
358 int unaligned;
359 u32 val = 0;
360
361 unaligned = spi_imx->count % 4;
362
363 if (!unaligned) {
364 spi_imx_buf_tx_swap_u32(spi_imx);
365 return;
366 }
367
368 if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
369 spi_imx_buf_tx_u16(spi_imx);
370 return;
371 }
372
373 while (unaligned--) {
374 if (spi_imx->tx_buf) {
375 val |= *(u8 *)spi_imx->tx_buf << (8 * unaligned);
376 spi_imx->tx_buf++;
377 }
378 spi_imx->count--;
379 }
380
381 writel(val, spi_imx->base + MXC_CSPITXDATA);
382 }
383
mx53_ecspi_rx_slave(struct spi_imx_data * spi_imx)384 static void mx53_ecspi_rx_slave(struct spi_imx_data *spi_imx)
385 {
386 u32 val = be32_to_cpu(readl(spi_imx->base + MXC_CSPIRXDATA));
387
388 if (spi_imx->rx_buf) {
389 int n_bytes = spi_imx->slave_burst % sizeof(val);
390
391 if (!n_bytes)
392 n_bytes = sizeof(val);
393
394 memcpy(spi_imx->rx_buf,
395 ((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
396
397 spi_imx->rx_buf += n_bytes;
398 spi_imx->slave_burst -= n_bytes;
399 }
400
401 spi_imx->remainder -= sizeof(u32);
402 }
403
mx53_ecspi_tx_slave(struct spi_imx_data * spi_imx)404 static void mx53_ecspi_tx_slave(struct spi_imx_data *spi_imx)
405 {
406 u32 val = 0;
407 int n_bytes = spi_imx->count % sizeof(val);
408
409 if (!n_bytes)
410 n_bytes = sizeof(val);
411
412 if (spi_imx->tx_buf) {
413 memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
414 spi_imx->tx_buf, n_bytes);
415 val = cpu_to_be32(val);
416 spi_imx->tx_buf += n_bytes;
417 }
418
419 spi_imx->count -= n_bytes;
420
421 writel(val, spi_imx->base + MXC_CSPITXDATA);
422 }
423
424 /* MX51 eCSPI */
mx51_ecspi_clkdiv(struct spi_imx_data * spi_imx,unsigned int fspi,unsigned int * fres)425 static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
426 unsigned int fspi, unsigned int *fres)
427 {
428 /*
429 * there are two 4-bit dividers, the pre-divider divides by
430 * $pre, the post-divider by 2^$post
431 */
432 unsigned int pre, post;
433 unsigned int fin = spi_imx->spi_clk;
434
435 if (unlikely(fspi > fin))
436 return 0;
437
438 post = fls(fin) - fls(fspi);
439 if (fin > fspi << post)
440 post++;
441
442 /* now we have: (fin <= fspi << post) with post being minimal */
443
444 post = max(4U, post) - 4;
445 if (unlikely(post > 0xf)) {
446 dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
447 fspi, fin);
448 return 0xff;
449 }
450
451 pre = DIV_ROUND_UP(fin, fspi << post) - 1;
452
453 dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
454 __func__, fin, fspi, post, pre);
455
456 /* Resulting frequency for the SCLK line. */
457 *fres = (fin / (pre + 1)) >> post;
458
459 return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
460 (post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
461 }
462
mx51_ecspi_intctrl(struct spi_imx_data * spi_imx,int enable)463 static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
464 {
465 unsigned val = 0;
466
467 if (enable & MXC_INT_TE)
468 val |= MX51_ECSPI_INT_TEEN;
469
470 if (enable & MXC_INT_RR)
471 val |= MX51_ECSPI_INT_RREN;
472
473 if (enable & MXC_INT_RDR)
474 val |= MX51_ECSPI_INT_RDREN;
475
476 writel(val, spi_imx->base + MX51_ECSPI_INT);
477 }
478
mx51_ecspi_trigger(struct spi_imx_data * spi_imx)479 static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
480 {
481 u32 reg;
482
483 reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
484 reg |= MX51_ECSPI_CTRL_XCH;
485 writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
486 }
487
mx51_ecspi_disable(struct spi_imx_data * spi_imx)488 static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
489 {
490 u32 ctrl;
491
492 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
493 ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
494 writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
495 }
496
mx51_ecspi_prepare_message(struct spi_imx_data * spi_imx,struct spi_message * msg)497 static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
498 struct spi_message *msg)
499 {
500 struct spi_device *spi = msg->spi;
501 u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
502 u32 testreg;
503 u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
504
505 /* set Master or Slave mode */
506 if (spi_imx->slave_mode)
507 ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
508 else
509 ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
510
511 /*
512 * Enable SPI_RDY handling (falling edge/level triggered).
513 */
514 if (spi->mode & SPI_READY)
515 ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
516
517 /* set chip select to use */
518 ctrl |= MX51_ECSPI_CTRL_CS(spi->chip_select);
519
520 /*
521 * The ctrl register must be written first, with the EN bit set other
522 * registers must not be written to.
523 */
524 writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
525
526 testreg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
527 if (spi->mode & SPI_LOOP)
528 testreg |= MX51_ECSPI_TESTREG_LBC;
529 else
530 testreg &= ~MX51_ECSPI_TESTREG_LBC;
531 writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
532
533 /*
534 * eCSPI burst completion by Chip Select signal in Slave mode
535 * is not functional for imx53 Soc, config SPI burst completed when
536 * BURST_LENGTH + 1 bits are received
537 */
538 if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
539 cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
540 else
541 cfg |= MX51_ECSPI_CONFIG_SBBCTRL(spi->chip_select);
542
543 if (spi->mode & SPI_CPHA)
544 cfg |= MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
545 else
546 cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(spi->chip_select);
547
548 if (spi->mode & SPI_CPOL) {
549 cfg |= MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
550 cfg |= MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
551 } else {
552 cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(spi->chip_select);
553 cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi->chip_select);
554 }
555
556 if (spi->mode & SPI_CS_HIGH)
557 cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
558 else
559 cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(spi->chip_select);
560
561 writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
562
563 return 0;
564 }
565
mx51_ecspi_prepare_transfer(struct spi_imx_data * spi_imx,struct spi_device * spi,struct spi_transfer * t)566 static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
567 struct spi_device *spi,
568 struct spi_transfer *t)
569 {
570 u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
571 u32 clk = t->speed_hz, delay;
572
573 /* Clear BL field and set the right value */
574 ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
575 if (spi_imx->slave_mode && is_imx53_ecspi(spi_imx))
576 ctrl |= (spi_imx->slave_burst * 8 - 1)
577 << MX51_ECSPI_CTRL_BL_OFFSET;
578 else
579 ctrl |= (spi_imx->bits_per_word - 1)
580 << MX51_ECSPI_CTRL_BL_OFFSET;
581
582 /* set clock speed */
583 ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
584 0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
585 ctrl |= mx51_ecspi_clkdiv(spi_imx, t->speed_hz, &clk);
586 spi_imx->spi_bus_clk = clk;
587
588 if (spi_imx->usedma)
589 ctrl |= MX51_ECSPI_CTRL_SMC;
590
591 writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
592
593 /*
594 * Wait until the changes in the configuration register CONFIGREG
595 * propagate into the hardware. It takes exactly one tick of the
596 * SCLK clock, but we will wait two SCLK clock just to be sure. The
597 * effect of the delay it takes for the hardware to apply changes
598 * is noticable if the SCLK clock run very slow. In such a case, if
599 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
600 * be asserted before the SCLK polarity changes, which would disrupt
601 * the SPI communication as the device on the other end would consider
602 * the change of SCLK polarity as a clock tick already.
603 */
604 delay = (2 * 1000000) / clk;
605 if (likely(delay < 10)) /* SCLK is faster than 100 kHz */
606 udelay(delay);
607 else /* SCLK is _very_ slow */
608 usleep_range(delay, delay + 10);
609
610 return 0;
611 }
612
mx51_setup_wml(struct spi_imx_data * spi_imx)613 static void mx51_setup_wml(struct spi_imx_data *spi_imx)
614 {
615 /*
616 * Configure the DMA register: setup the watermark
617 * and enable DMA request.
618 */
619 writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) |
620 MX51_ECSPI_DMA_TX_WML(spi_imx->wml) |
621 MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
622 MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN |
623 MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
624 }
625
mx51_ecspi_rx_available(struct spi_imx_data * spi_imx)626 static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
627 {
628 return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
629 }
630
mx51_ecspi_reset(struct spi_imx_data * spi_imx)631 static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
632 {
633 /* drain receive buffer */
634 while (mx51_ecspi_rx_available(spi_imx))
635 readl(spi_imx->base + MXC_CSPIRXDATA);
636 }
637
638 #define MX31_INTREG_TEEN (1 << 0)
639 #define MX31_INTREG_RREN (1 << 3)
640
641 #define MX31_CSPICTRL_ENABLE (1 << 0)
642 #define MX31_CSPICTRL_MASTER (1 << 1)
643 #define MX31_CSPICTRL_XCH (1 << 2)
644 #define MX31_CSPICTRL_SMC (1 << 3)
645 #define MX31_CSPICTRL_POL (1 << 4)
646 #define MX31_CSPICTRL_PHA (1 << 5)
647 #define MX31_CSPICTRL_SSCTL (1 << 6)
648 #define MX31_CSPICTRL_SSPOL (1 << 7)
649 #define MX31_CSPICTRL_BC_SHIFT 8
650 #define MX35_CSPICTRL_BL_SHIFT 20
651 #define MX31_CSPICTRL_CS_SHIFT 24
652 #define MX35_CSPICTRL_CS_SHIFT 12
653 #define MX31_CSPICTRL_DR_SHIFT 16
654
655 #define MX31_CSPI_DMAREG 0x10
656 #define MX31_DMAREG_RH_DEN (1<<4)
657 #define MX31_DMAREG_TH_DEN (1<<1)
658
659 #define MX31_CSPISTATUS 0x14
660 #define MX31_STATUS_RR (1 << 3)
661
662 #define MX31_CSPI_TESTREG 0x1C
663 #define MX31_TEST_LBC (1 << 14)
664
665 /* These functions also work for the i.MX35, but be aware that
666 * the i.MX35 has a slightly different register layout for bits
667 * we do not use here.
668 */
mx31_intctrl(struct spi_imx_data * spi_imx,int enable)669 static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
670 {
671 unsigned int val = 0;
672
673 if (enable & MXC_INT_TE)
674 val |= MX31_INTREG_TEEN;
675 if (enable & MXC_INT_RR)
676 val |= MX31_INTREG_RREN;
677
678 writel(val, spi_imx->base + MXC_CSPIINT);
679 }
680
mx31_trigger(struct spi_imx_data * spi_imx)681 static void mx31_trigger(struct spi_imx_data *spi_imx)
682 {
683 unsigned int reg;
684
685 reg = readl(spi_imx->base + MXC_CSPICTRL);
686 reg |= MX31_CSPICTRL_XCH;
687 writel(reg, spi_imx->base + MXC_CSPICTRL);
688 }
689
mx31_prepare_message(struct spi_imx_data * spi_imx,struct spi_message * msg)690 static int mx31_prepare_message(struct spi_imx_data *spi_imx,
691 struct spi_message *msg)
692 {
693 return 0;
694 }
695
mx31_prepare_transfer(struct spi_imx_data * spi_imx,struct spi_device * spi,struct spi_transfer * t)696 static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
697 struct spi_device *spi,
698 struct spi_transfer *t)
699 {
700 unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
701 unsigned int clk;
702
703 reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, t->speed_hz, &clk) <<
704 MX31_CSPICTRL_DR_SHIFT;
705 spi_imx->spi_bus_clk = clk;
706
707 if (is_imx35_cspi(spi_imx)) {
708 reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
709 reg |= MX31_CSPICTRL_SSCTL;
710 } else {
711 reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
712 }
713
714 if (spi->mode & SPI_CPHA)
715 reg |= MX31_CSPICTRL_PHA;
716 if (spi->mode & SPI_CPOL)
717 reg |= MX31_CSPICTRL_POL;
718 if (spi->mode & SPI_CS_HIGH)
719 reg |= MX31_CSPICTRL_SSPOL;
720 if (!gpio_is_valid(spi->cs_gpio))
721 reg |= (spi->chip_select) <<
722 (is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
723 MX31_CSPICTRL_CS_SHIFT);
724
725 if (spi_imx->usedma)
726 reg |= MX31_CSPICTRL_SMC;
727
728 writel(reg, spi_imx->base + MXC_CSPICTRL);
729
730 reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
731 if (spi->mode & SPI_LOOP)
732 reg |= MX31_TEST_LBC;
733 else
734 reg &= ~MX31_TEST_LBC;
735 writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
736
737 if (spi_imx->usedma) {
738 /*
739 * configure DMA requests when RXFIFO is half full and
740 * when TXFIFO is half empty
741 */
742 writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
743 spi_imx->base + MX31_CSPI_DMAREG);
744 }
745
746 return 0;
747 }
748
mx31_rx_available(struct spi_imx_data * spi_imx)749 static int mx31_rx_available(struct spi_imx_data *spi_imx)
750 {
751 return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
752 }
753
mx31_reset(struct spi_imx_data * spi_imx)754 static void mx31_reset(struct spi_imx_data *spi_imx)
755 {
756 /* drain receive buffer */
757 while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
758 readl(spi_imx->base + MXC_CSPIRXDATA);
759 }
760
761 #define MX21_INTREG_RR (1 << 4)
762 #define MX21_INTREG_TEEN (1 << 9)
763 #define MX21_INTREG_RREN (1 << 13)
764
765 #define MX21_CSPICTRL_POL (1 << 5)
766 #define MX21_CSPICTRL_PHA (1 << 6)
767 #define MX21_CSPICTRL_SSPOL (1 << 8)
768 #define MX21_CSPICTRL_XCH (1 << 9)
769 #define MX21_CSPICTRL_ENABLE (1 << 10)
770 #define MX21_CSPICTRL_MASTER (1 << 11)
771 #define MX21_CSPICTRL_DR_SHIFT 14
772 #define MX21_CSPICTRL_CS_SHIFT 19
773
mx21_intctrl(struct spi_imx_data * spi_imx,int enable)774 static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
775 {
776 unsigned int val = 0;
777
778 if (enable & MXC_INT_TE)
779 val |= MX21_INTREG_TEEN;
780 if (enable & MXC_INT_RR)
781 val |= MX21_INTREG_RREN;
782
783 writel(val, spi_imx->base + MXC_CSPIINT);
784 }
785
mx21_trigger(struct spi_imx_data * spi_imx)786 static void mx21_trigger(struct spi_imx_data *spi_imx)
787 {
788 unsigned int reg;
789
790 reg = readl(spi_imx->base + MXC_CSPICTRL);
791 reg |= MX21_CSPICTRL_XCH;
792 writel(reg, spi_imx->base + MXC_CSPICTRL);
793 }
794
mx21_prepare_message(struct spi_imx_data * spi_imx,struct spi_message * msg)795 static int mx21_prepare_message(struct spi_imx_data *spi_imx,
796 struct spi_message *msg)
797 {
798 return 0;
799 }
800
mx21_prepare_transfer(struct spi_imx_data * spi_imx,struct spi_device * spi,struct spi_transfer * t)801 static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
802 struct spi_device *spi,
803 struct spi_transfer *t)
804 {
805 unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
806 unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
807 unsigned int clk;
808
809 reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, t->speed_hz, max, &clk)
810 << MX21_CSPICTRL_DR_SHIFT;
811 spi_imx->spi_bus_clk = clk;
812
813 reg |= spi_imx->bits_per_word - 1;
814
815 if (spi->mode & SPI_CPHA)
816 reg |= MX21_CSPICTRL_PHA;
817 if (spi->mode & SPI_CPOL)
818 reg |= MX21_CSPICTRL_POL;
819 if (spi->mode & SPI_CS_HIGH)
820 reg |= MX21_CSPICTRL_SSPOL;
821 if (!gpio_is_valid(spi->cs_gpio))
822 reg |= spi->chip_select << MX21_CSPICTRL_CS_SHIFT;
823
824 writel(reg, spi_imx->base + MXC_CSPICTRL);
825
826 return 0;
827 }
828
mx21_rx_available(struct spi_imx_data * spi_imx)829 static int mx21_rx_available(struct spi_imx_data *spi_imx)
830 {
831 return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
832 }
833
mx21_reset(struct spi_imx_data * spi_imx)834 static void mx21_reset(struct spi_imx_data *spi_imx)
835 {
836 writel(1, spi_imx->base + MXC_RESET);
837 }
838
839 #define MX1_INTREG_RR (1 << 3)
840 #define MX1_INTREG_TEEN (1 << 8)
841 #define MX1_INTREG_RREN (1 << 11)
842
843 #define MX1_CSPICTRL_POL (1 << 4)
844 #define MX1_CSPICTRL_PHA (1 << 5)
845 #define MX1_CSPICTRL_XCH (1 << 8)
846 #define MX1_CSPICTRL_ENABLE (1 << 9)
847 #define MX1_CSPICTRL_MASTER (1 << 10)
848 #define MX1_CSPICTRL_DR_SHIFT 13
849
mx1_intctrl(struct spi_imx_data * spi_imx,int enable)850 static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
851 {
852 unsigned int val = 0;
853
854 if (enable & MXC_INT_TE)
855 val |= MX1_INTREG_TEEN;
856 if (enable & MXC_INT_RR)
857 val |= MX1_INTREG_RREN;
858
859 writel(val, spi_imx->base + MXC_CSPIINT);
860 }
861
mx1_trigger(struct spi_imx_data * spi_imx)862 static void mx1_trigger(struct spi_imx_data *spi_imx)
863 {
864 unsigned int reg;
865
866 reg = readl(spi_imx->base + MXC_CSPICTRL);
867 reg |= MX1_CSPICTRL_XCH;
868 writel(reg, spi_imx->base + MXC_CSPICTRL);
869 }
870
mx1_prepare_message(struct spi_imx_data * spi_imx,struct spi_message * msg)871 static int mx1_prepare_message(struct spi_imx_data *spi_imx,
872 struct spi_message *msg)
873 {
874 return 0;
875 }
876
mx1_prepare_transfer(struct spi_imx_data * spi_imx,struct spi_device * spi,struct spi_transfer * t)877 static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
878 struct spi_device *spi,
879 struct spi_transfer *t)
880 {
881 unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
882 unsigned int clk;
883
884 reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, t->speed_hz, &clk) <<
885 MX1_CSPICTRL_DR_SHIFT;
886 spi_imx->spi_bus_clk = clk;
887
888 reg |= spi_imx->bits_per_word - 1;
889
890 if (spi->mode & SPI_CPHA)
891 reg |= MX1_CSPICTRL_PHA;
892 if (spi->mode & SPI_CPOL)
893 reg |= MX1_CSPICTRL_POL;
894
895 writel(reg, spi_imx->base + MXC_CSPICTRL);
896
897 return 0;
898 }
899
mx1_rx_available(struct spi_imx_data * spi_imx)900 static int mx1_rx_available(struct spi_imx_data *spi_imx)
901 {
902 return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
903 }
904
mx1_reset(struct spi_imx_data * spi_imx)905 static void mx1_reset(struct spi_imx_data *spi_imx)
906 {
907 writel(1, spi_imx->base + MXC_RESET);
908 }
909
910 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
911 .intctrl = mx1_intctrl,
912 .prepare_message = mx1_prepare_message,
913 .prepare_transfer = mx1_prepare_transfer,
914 .trigger = mx1_trigger,
915 .rx_available = mx1_rx_available,
916 .reset = mx1_reset,
917 .fifo_size = 8,
918 .has_dmamode = false,
919 .dynamic_burst = false,
920 .has_slavemode = false,
921 .devtype = IMX1_CSPI,
922 };
923
924 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
925 .intctrl = mx21_intctrl,
926 .prepare_message = mx21_prepare_message,
927 .prepare_transfer = mx21_prepare_transfer,
928 .trigger = mx21_trigger,
929 .rx_available = mx21_rx_available,
930 .reset = mx21_reset,
931 .fifo_size = 8,
932 .has_dmamode = false,
933 .dynamic_burst = false,
934 .has_slavemode = false,
935 .devtype = IMX21_CSPI,
936 };
937
938 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
939 /* i.mx27 cspi shares the functions with i.mx21 one */
940 .intctrl = mx21_intctrl,
941 .prepare_message = mx21_prepare_message,
942 .prepare_transfer = mx21_prepare_transfer,
943 .trigger = mx21_trigger,
944 .rx_available = mx21_rx_available,
945 .reset = mx21_reset,
946 .fifo_size = 8,
947 .has_dmamode = false,
948 .dynamic_burst = false,
949 .has_slavemode = false,
950 .devtype = IMX27_CSPI,
951 };
952
953 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
954 .intctrl = mx31_intctrl,
955 .prepare_message = mx31_prepare_message,
956 .prepare_transfer = mx31_prepare_transfer,
957 .trigger = mx31_trigger,
958 .rx_available = mx31_rx_available,
959 .reset = mx31_reset,
960 .fifo_size = 8,
961 .has_dmamode = false,
962 .dynamic_burst = false,
963 .has_slavemode = false,
964 .devtype = IMX31_CSPI,
965 };
966
967 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
968 /* i.mx35 and later cspi shares the functions with i.mx31 one */
969 .intctrl = mx31_intctrl,
970 .prepare_message = mx31_prepare_message,
971 .prepare_transfer = mx31_prepare_transfer,
972 .trigger = mx31_trigger,
973 .rx_available = mx31_rx_available,
974 .reset = mx31_reset,
975 .fifo_size = 8,
976 .has_dmamode = true,
977 .dynamic_burst = false,
978 .has_slavemode = false,
979 .devtype = IMX35_CSPI,
980 };
981
982 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
983 .intctrl = mx51_ecspi_intctrl,
984 .prepare_message = mx51_ecspi_prepare_message,
985 .prepare_transfer = mx51_ecspi_prepare_transfer,
986 .trigger = mx51_ecspi_trigger,
987 .rx_available = mx51_ecspi_rx_available,
988 .reset = mx51_ecspi_reset,
989 .setup_wml = mx51_setup_wml,
990 .fifo_size = 64,
991 .has_dmamode = true,
992 .dynamic_burst = true,
993 .has_slavemode = true,
994 .disable = mx51_ecspi_disable,
995 .devtype = IMX51_ECSPI,
996 };
997
998 static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
999 .intctrl = mx51_ecspi_intctrl,
1000 .prepare_message = mx51_ecspi_prepare_message,
1001 .prepare_transfer = mx51_ecspi_prepare_transfer,
1002 .trigger = mx51_ecspi_trigger,
1003 .rx_available = mx51_ecspi_rx_available,
1004 .reset = mx51_ecspi_reset,
1005 .fifo_size = 64,
1006 .has_dmamode = true,
1007 .has_slavemode = true,
1008 .disable = mx51_ecspi_disable,
1009 .devtype = IMX53_ECSPI,
1010 };
1011
1012 static const struct platform_device_id spi_imx_devtype[] = {
1013 {
1014 .name = "imx1-cspi",
1015 .driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
1016 }, {
1017 .name = "imx21-cspi",
1018 .driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
1019 }, {
1020 .name = "imx27-cspi",
1021 .driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
1022 }, {
1023 .name = "imx31-cspi",
1024 .driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
1025 }, {
1026 .name = "imx35-cspi",
1027 .driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
1028 }, {
1029 .name = "imx51-ecspi",
1030 .driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
1031 }, {
1032 .name = "imx53-ecspi",
1033 .driver_data = (kernel_ulong_t) &imx53_ecspi_devtype_data,
1034 }, {
1035 /* sentinel */
1036 }
1037 };
1038
1039 static const struct of_device_id spi_imx_dt_ids[] = {
1040 { .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
1041 { .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
1042 { .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
1043 { .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
1044 { .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
1045 { .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
1046 { .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
1047 { /* sentinel */ }
1048 };
1049 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
1050
spi_imx_chipselect(struct spi_device * spi,int is_active)1051 static void spi_imx_chipselect(struct spi_device *spi, int is_active)
1052 {
1053 int active = is_active != BITBANG_CS_INACTIVE;
1054 int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
1055
1056 if (spi->mode & SPI_NO_CS)
1057 return;
1058
1059 if (!gpio_is_valid(spi->cs_gpio))
1060 return;
1061
1062 gpio_set_value(spi->cs_gpio, dev_is_lowactive ^ active);
1063 }
1064
spi_imx_set_burst_len(struct spi_imx_data * spi_imx,int n_bits)1065 static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
1066 {
1067 u32 ctrl;
1068
1069 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
1070 ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
1071 ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
1072 writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
1073 }
1074
spi_imx_push(struct spi_imx_data * spi_imx)1075 static void spi_imx_push(struct spi_imx_data *spi_imx)
1076 {
1077 unsigned int burst_len, fifo_words;
1078
1079 if (spi_imx->dynamic_burst)
1080 fifo_words = 4;
1081 else
1082 fifo_words = spi_imx_bytes_per_word(spi_imx->bits_per_word);
1083 /*
1084 * Reload the FIFO when the remaining bytes to be transferred in the
1085 * current burst is 0. This only applies when bits_per_word is a
1086 * multiple of 8.
1087 */
1088 if (!spi_imx->remainder) {
1089 if (spi_imx->dynamic_burst) {
1090
1091 /* We need to deal unaligned data first */
1092 burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
1093
1094 if (!burst_len)
1095 burst_len = MX51_ECSPI_CTRL_MAX_BURST;
1096
1097 spi_imx_set_burst_len(spi_imx, burst_len * 8);
1098
1099 spi_imx->remainder = burst_len;
1100 } else {
1101 spi_imx->remainder = fifo_words;
1102 }
1103 }
1104
1105 while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
1106 if (!spi_imx->count)
1107 break;
1108 if (spi_imx->dynamic_burst &&
1109 spi_imx->txfifo >= DIV_ROUND_UP(spi_imx->remainder,
1110 fifo_words))
1111 break;
1112 spi_imx->tx(spi_imx);
1113 spi_imx->txfifo++;
1114 }
1115
1116 if (!spi_imx->slave_mode)
1117 spi_imx->devtype_data->trigger(spi_imx);
1118 }
1119
spi_imx_isr(int irq,void * dev_id)1120 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
1121 {
1122 struct spi_imx_data *spi_imx = dev_id;
1123
1124 while (spi_imx->txfifo &&
1125 spi_imx->devtype_data->rx_available(spi_imx)) {
1126 spi_imx->rx(spi_imx);
1127 spi_imx->txfifo--;
1128 }
1129
1130 if (spi_imx->count) {
1131 spi_imx_push(spi_imx);
1132 return IRQ_HANDLED;
1133 }
1134
1135 if (spi_imx->txfifo) {
1136 /* No data left to push, but still waiting for rx data,
1137 * enable receive data available interrupt.
1138 */
1139 spi_imx->devtype_data->intctrl(
1140 spi_imx, MXC_INT_RR);
1141 return IRQ_HANDLED;
1142 }
1143
1144 spi_imx->devtype_data->intctrl(spi_imx, 0);
1145 complete(&spi_imx->xfer_done);
1146
1147 return IRQ_HANDLED;
1148 }
1149
spi_imx_dma_configure(struct spi_master * master)1150 static int spi_imx_dma_configure(struct spi_master *master)
1151 {
1152 int ret;
1153 enum dma_slave_buswidth buswidth;
1154 struct dma_slave_config rx = {}, tx = {};
1155 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1156
1157 switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
1158 case 4:
1159 buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
1160 break;
1161 case 2:
1162 buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
1163 break;
1164 case 1:
1165 buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
1166 break;
1167 default:
1168 return -EINVAL;
1169 }
1170
1171 tx.direction = DMA_MEM_TO_DEV;
1172 tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
1173 tx.dst_addr_width = buswidth;
1174 tx.dst_maxburst = spi_imx->wml;
1175 ret = dmaengine_slave_config(master->dma_tx, &tx);
1176 if (ret) {
1177 dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
1178 return ret;
1179 }
1180
1181 rx.direction = DMA_DEV_TO_MEM;
1182 rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
1183 rx.src_addr_width = buswidth;
1184 rx.src_maxburst = spi_imx->wml;
1185 ret = dmaengine_slave_config(master->dma_rx, &rx);
1186 if (ret) {
1187 dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
1188 return ret;
1189 }
1190
1191 return 0;
1192 }
1193
spi_imx_setupxfer(struct spi_device * spi,struct spi_transfer * t)1194 static int spi_imx_setupxfer(struct spi_device *spi,
1195 struct spi_transfer *t)
1196 {
1197 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1198
1199 if (!t)
1200 return 0;
1201
1202 spi_imx->bits_per_word = t->bits_per_word;
1203
1204 /*
1205 * Initialize the functions for transfer. To transfer non byte-aligned
1206 * words, we have to use multiple word-size bursts, we can't use
1207 * dynamic_burst in that case.
1208 */
1209 if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode &&
1210 (spi_imx->bits_per_word == 8 ||
1211 spi_imx->bits_per_word == 16 ||
1212 spi_imx->bits_per_word == 32)) {
1213
1214 spi_imx->rx = spi_imx_buf_rx_swap;
1215 spi_imx->tx = spi_imx_buf_tx_swap;
1216 spi_imx->dynamic_burst = 1;
1217
1218 } else {
1219 if (spi_imx->bits_per_word <= 8) {
1220 spi_imx->rx = spi_imx_buf_rx_u8;
1221 spi_imx->tx = spi_imx_buf_tx_u8;
1222 } else if (spi_imx->bits_per_word <= 16) {
1223 spi_imx->rx = spi_imx_buf_rx_u16;
1224 spi_imx->tx = spi_imx_buf_tx_u16;
1225 } else {
1226 spi_imx->rx = spi_imx_buf_rx_u32;
1227 spi_imx->tx = spi_imx_buf_tx_u32;
1228 }
1229 spi_imx->dynamic_burst = 0;
1230 }
1231
1232 if (spi_imx_can_dma(spi_imx->bitbang.master, spi, t))
1233 spi_imx->usedma = 1;
1234 else
1235 spi_imx->usedma = 0;
1236
1237 if (is_imx53_ecspi(spi_imx) && spi_imx->slave_mode) {
1238 spi_imx->rx = mx53_ecspi_rx_slave;
1239 spi_imx->tx = mx53_ecspi_tx_slave;
1240 spi_imx->slave_burst = t->len;
1241 }
1242
1243 spi_imx->devtype_data->prepare_transfer(spi_imx, spi, t);
1244
1245 return 0;
1246 }
1247
spi_imx_sdma_exit(struct spi_imx_data * spi_imx)1248 static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
1249 {
1250 struct spi_master *master = spi_imx->bitbang.master;
1251
1252 if (master->dma_rx) {
1253 dma_release_channel(master->dma_rx);
1254 master->dma_rx = NULL;
1255 }
1256
1257 if (master->dma_tx) {
1258 dma_release_channel(master->dma_tx);
1259 master->dma_tx = NULL;
1260 }
1261 }
1262
spi_imx_sdma_init(struct device * dev,struct spi_imx_data * spi_imx,struct spi_master * master)1263 static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
1264 struct spi_master *master)
1265 {
1266 int ret;
1267
1268 /* use pio mode for i.mx6dl chip TKT238285 */
1269 if (of_machine_is_compatible("fsl,imx6dl"))
1270 return 0;
1271
1272 spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
1273
1274 /* Prepare for TX DMA: */
1275 master->dma_tx = dma_request_slave_channel_reason(dev, "tx");
1276 if (IS_ERR(master->dma_tx)) {
1277 ret = PTR_ERR(master->dma_tx);
1278 dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
1279 master->dma_tx = NULL;
1280 goto err;
1281 }
1282
1283 /* Prepare for RX : */
1284 master->dma_rx = dma_request_slave_channel_reason(dev, "rx");
1285 if (IS_ERR(master->dma_rx)) {
1286 ret = PTR_ERR(master->dma_rx);
1287 dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);
1288 master->dma_rx = NULL;
1289 goto err;
1290 }
1291
1292 init_completion(&spi_imx->dma_rx_completion);
1293 init_completion(&spi_imx->dma_tx_completion);
1294 master->can_dma = spi_imx_can_dma;
1295 master->max_dma_len = MAX_SDMA_BD_BYTES;
1296 spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
1297 SPI_MASTER_MUST_TX;
1298
1299 return 0;
1300 err:
1301 spi_imx_sdma_exit(spi_imx);
1302 return ret;
1303 }
1304
spi_imx_dma_rx_callback(void * cookie)1305 static void spi_imx_dma_rx_callback(void *cookie)
1306 {
1307 struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1308
1309 complete(&spi_imx->dma_rx_completion);
1310 }
1311
spi_imx_dma_tx_callback(void * cookie)1312 static void spi_imx_dma_tx_callback(void *cookie)
1313 {
1314 struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1315
1316 complete(&spi_imx->dma_tx_completion);
1317 }
1318
spi_imx_calculate_timeout(struct spi_imx_data * spi_imx,int size)1319 static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1320 {
1321 unsigned long timeout = 0;
1322
1323 /* Time with actual data transfer and CS change delay related to HW */
1324 timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1325
1326 /* Add extra second for scheduler related activities */
1327 timeout += 1;
1328
1329 /* Double calculated timeout */
1330 return msecs_to_jiffies(2 * timeout * MSEC_PER_SEC);
1331 }
1332
spi_imx_dma_transfer(struct spi_imx_data * spi_imx,struct spi_transfer * transfer)1333 static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1334 struct spi_transfer *transfer)
1335 {
1336 struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1337 unsigned long transfer_timeout;
1338 unsigned long timeout;
1339 struct spi_master *master = spi_imx->bitbang.master;
1340 struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1341 struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
1342 unsigned int bytes_per_word, i;
1343 int ret;
1344
1345 /* Get the right burst length from the last sg to ensure no tail data */
1346 bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
1347 for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
1348 if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
1349 break;
1350 }
1351 /* Use 1 as wml in case no available burst length got */
1352 if (i == 0)
1353 i = 1;
1354
1355 spi_imx->wml = i;
1356
1357 ret = spi_imx_dma_configure(master);
1358 if (ret)
1359 return ret;
1360
1361 if (!spi_imx->devtype_data->setup_wml) {
1362 dev_err(spi_imx->dev, "No setup_wml()?\n");
1363 return -EINVAL;
1364 }
1365 spi_imx->devtype_data->setup_wml(spi_imx);
1366
1367 /*
1368 * The TX DMA setup starts the transfer, so make sure RX is configured
1369 * before TX.
1370 */
1371 desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
1372 rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1373 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1374 if (!desc_rx)
1375 return -EINVAL;
1376
1377 desc_rx->callback = spi_imx_dma_rx_callback;
1378 desc_rx->callback_param = (void *)spi_imx;
1379 dmaengine_submit(desc_rx);
1380 reinit_completion(&spi_imx->dma_rx_completion);
1381 dma_async_issue_pending(master->dma_rx);
1382
1383 desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
1384 tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1385 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1386 if (!desc_tx) {
1387 dmaengine_terminate_all(master->dma_tx);
1388 return -EINVAL;
1389 }
1390
1391 desc_tx->callback = spi_imx_dma_tx_callback;
1392 desc_tx->callback_param = (void *)spi_imx;
1393 dmaengine_submit(desc_tx);
1394 reinit_completion(&spi_imx->dma_tx_completion);
1395 dma_async_issue_pending(master->dma_tx);
1396
1397 transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1398
1399 /* Wait SDMA to finish the data transfer.*/
1400 timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1401 transfer_timeout);
1402 if (!timeout) {
1403 dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1404 dmaengine_terminate_all(master->dma_tx);
1405 dmaengine_terminate_all(master->dma_rx);
1406 return -ETIMEDOUT;
1407 }
1408
1409 timeout = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1410 transfer_timeout);
1411 if (!timeout) {
1412 dev_err(&master->dev, "I/O Error in DMA RX\n");
1413 spi_imx->devtype_data->reset(spi_imx);
1414 dmaengine_terminate_all(master->dma_rx);
1415 return -ETIMEDOUT;
1416 }
1417
1418 return transfer->len;
1419 }
1420
spi_imx_pio_transfer(struct spi_device * spi,struct spi_transfer * transfer)1421 static int spi_imx_pio_transfer(struct spi_device *spi,
1422 struct spi_transfer *transfer)
1423 {
1424 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1425 unsigned long transfer_timeout;
1426 unsigned long timeout;
1427
1428 spi_imx->tx_buf = transfer->tx_buf;
1429 spi_imx->rx_buf = transfer->rx_buf;
1430 spi_imx->count = transfer->len;
1431 spi_imx->txfifo = 0;
1432 spi_imx->remainder = 0;
1433
1434 reinit_completion(&spi_imx->xfer_done);
1435
1436 spi_imx_push(spi_imx);
1437
1438 spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1439
1440 transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1441
1442 timeout = wait_for_completion_timeout(&spi_imx->xfer_done,
1443 transfer_timeout);
1444 if (!timeout) {
1445 dev_err(&spi->dev, "I/O Error in PIO\n");
1446 spi_imx->devtype_data->reset(spi_imx);
1447 return -ETIMEDOUT;
1448 }
1449
1450 return transfer->len;
1451 }
1452
spi_imx_pio_transfer_slave(struct spi_device * spi,struct spi_transfer * transfer)1453 static int spi_imx_pio_transfer_slave(struct spi_device *spi,
1454 struct spi_transfer *transfer)
1455 {
1456 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1457 int ret = transfer->len;
1458
1459 if (is_imx53_ecspi(spi_imx) &&
1460 transfer->len > MX53_MAX_TRANSFER_BYTES) {
1461 dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
1462 MX53_MAX_TRANSFER_BYTES);
1463 return -EMSGSIZE;
1464 }
1465
1466 spi_imx->tx_buf = transfer->tx_buf;
1467 spi_imx->rx_buf = transfer->rx_buf;
1468 spi_imx->count = transfer->len;
1469 spi_imx->txfifo = 0;
1470 spi_imx->remainder = 0;
1471
1472 reinit_completion(&spi_imx->xfer_done);
1473 spi_imx->slave_aborted = false;
1474
1475 spi_imx_push(spi_imx);
1476
1477 spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
1478
1479 if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
1480 spi_imx->slave_aborted) {
1481 dev_dbg(&spi->dev, "interrupted\n");
1482 ret = -EINTR;
1483 }
1484
1485 /* ecspi has a HW issue when works in Slave mode,
1486 * after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
1487 * ECSPI_TXDATA keeps shift out the last word data,
1488 * so we have to disable ECSPI when in slave mode after the
1489 * transfer completes
1490 */
1491 if (spi_imx->devtype_data->disable)
1492 spi_imx->devtype_data->disable(spi_imx);
1493
1494 return ret;
1495 }
1496
spi_imx_transfer(struct spi_device * spi,struct spi_transfer * transfer)1497 static int spi_imx_transfer(struct spi_device *spi,
1498 struct spi_transfer *transfer)
1499 {
1500 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1501
1502 /* flush rxfifo before transfer */
1503 while (spi_imx->devtype_data->rx_available(spi_imx))
1504 readl(spi_imx->base + MXC_CSPIRXDATA);
1505
1506 if (spi_imx->slave_mode)
1507 return spi_imx_pio_transfer_slave(spi, transfer);
1508
1509 if (spi_imx->usedma)
1510 return spi_imx_dma_transfer(spi_imx, transfer);
1511 else
1512 return spi_imx_pio_transfer(spi, transfer);
1513 }
1514
spi_imx_setup(struct spi_device * spi)1515 static int spi_imx_setup(struct spi_device *spi)
1516 {
1517 dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1518 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1519
1520 if (spi->mode & SPI_NO_CS)
1521 return 0;
1522
1523 if (gpio_is_valid(spi->cs_gpio))
1524 gpio_direction_output(spi->cs_gpio,
1525 spi->mode & SPI_CS_HIGH ? 0 : 1);
1526
1527 spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
1528
1529 return 0;
1530 }
1531
spi_imx_cleanup(struct spi_device * spi)1532 static void spi_imx_cleanup(struct spi_device *spi)
1533 {
1534 }
1535
1536 static int
spi_imx_prepare_message(struct spi_master * master,struct spi_message * msg)1537 spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1538 {
1539 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1540 int ret;
1541
1542 ret = clk_enable(spi_imx->clk_per);
1543 if (ret)
1544 return ret;
1545
1546 ret = clk_enable(spi_imx->clk_ipg);
1547 if (ret) {
1548 clk_disable(spi_imx->clk_per);
1549 return ret;
1550 }
1551
1552 ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
1553 if (ret) {
1554 clk_disable(spi_imx->clk_ipg);
1555 clk_disable(spi_imx->clk_per);
1556 }
1557
1558 return ret;
1559 }
1560
1561 static int
spi_imx_unprepare_message(struct spi_master * master,struct spi_message * msg)1562 spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1563 {
1564 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1565
1566 clk_disable(spi_imx->clk_ipg);
1567 clk_disable(spi_imx->clk_per);
1568 return 0;
1569 }
1570
spi_imx_slave_abort(struct spi_master * master)1571 static int spi_imx_slave_abort(struct spi_master *master)
1572 {
1573 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1574
1575 spi_imx->slave_aborted = true;
1576 complete(&spi_imx->xfer_done);
1577
1578 return 0;
1579 }
1580
spi_imx_probe(struct platform_device * pdev)1581 static int spi_imx_probe(struct platform_device *pdev)
1582 {
1583 struct device_node *np = pdev->dev.of_node;
1584 const struct of_device_id *of_id =
1585 of_match_device(spi_imx_dt_ids, &pdev->dev);
1586 struct spi_imx_master *mxc_platform_info =
1587 dev_get_platdata(&pdev->dev);
1588 struct spi_master *master;
1589 struct spi_imx_data *spi_imx;
1590 struct resource *res;
1591 int i, ret, irq, spi_drctl;
1592 const struct spi_imx_devtype_data *devtype_data = of_id ? of_id->data :
1593 (struct spi_imx_devtype_data *)pdev->id_entry->driver_data;
1594 bool slave_mode;
1595
1596 if (!np && !mxc_platform_info) {
1597 dev_err(&pdev->dev, "can't get the platform data\n");
1598 return -EINVAL;
1599 }
1600
1601 slave_mode = devtype_data->has_slavemode &&
1602 of_property_read_bool(np, "spi-slave");
1603 if (slave_mode)
1604 master = spi_alloc_slave(&pdev->dev,
1605 sizeof(struct spi_imx_data));
1606 else
1607 master = spi_alloc_master(&pdev->dev,
1608 sizeof(struct spi_imx_data));
1609 if (!master)
1610 return -ENOMEM;
1611
1612 ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
1613 if ((ret < 0) || (spi_drctl >= 0x3)) {
1614 /* '11' is reserved */
1615 spi_drctl = 0;
1616 }
1617
1618 platform_set_drvdata(pdev, master);
1619
1620 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1621 master->bus_num = np ? -1 : pdev->id;
1622
1623 spi_imx = spi_master_get_devdata(master);
1624 spi_imx->bitbang.master = master;
1625 spi_imx->dev = &pdev->dev;
1626 spi_imx->slave_mode = slave_mode;
1627
1628 spi_imx->devtype_data = devtype_data;
1629
1630 /* Get number of chip selects, either platform data or OF */
1631 if (mxc_platform_info) {
1632 master->num_chipselect = mxc_platform_info->num_chipselect;
1633 if (mxc_platform_info->chipselect) {
1634 master->cs_gpios = devm_kcalloc(&master->dev,
1635 master->num_chipselect, sizeof(int),
1636 GFP_KERNEL);
1637 if (!master->cs_gpios)
1638 return -ENOMEM;
1639
1640 for (i = 0; i < master->num_chipselect; i++)
1641 master->cs_gpios[i] = mxc_platform_info->chipselect[i];
1642 }
1643 } else {
1644 u32 num_cs;
1645
1646 if (!of_property_read_u32(np, "num-cs", &num_cs))
1647 master->num_chipselect = num_cs;
1648 /* If not preset, default value of 1 is used */
1649 }
1650
1651 spi_imx->bitbang.chipselect = spi_imx_chipselect;
1652 spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1653 spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1654 spi_imx->bitbang.master->setup = spi_imx_setup;
1655 spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1656 spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1657 spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1658 spi_imx->bitbang.master->slave_abort = spi_imx_slave_abort;
1659 spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
1660 | SPI_NO_CS;
1661 if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
1662 is_imx53_ecspi(spi_imx))
1663 spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY;
1664
1665 spi_imx->spi_drctl = spi_drctl;
1666
1667 init_completion(&spi_imx->xfer_done);
1668
1669 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1670 spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1671 if (IS_ERR(spi_imx->base)) {
1672 ret = PTR_ERR(spi_imx->base);
1673 goto out_master_put;
1674 }
1675 spi_imx->base_phys = res->start;
1676
1677 irq = platform_get_irq(pdev, 0);
1678 if (irq < 0) {
1679 ret = irq;
1680 goto out_master_put;
1681 }
1682
1683 ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1684 dev_name(&pdev->dev), spi_imx);
1685 if (ret) {
1686 dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1687 goto out_master_put;
1688 }
1689
1690 spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1691 if (IS_ERR(spi_imx->clk_ipg)) {
1692 ret = PTR_ERR(spi_imx->clk_ipg);
1693 goto out_master_put;
1694 }
1695
1696 spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1697 if (IS_ERR(spi_imx->clk_per)) {
1698 ret = PTR_ERR(spi_imx->clk_per);
1699 goto out_master_put;
1700 }
1701
1702 ret = clk_prepare_enable(spi_imx->clk_per);
1703 if (ret)
1704 goto out_master_put;
1705
1706 ret = clk_prepare_enable(spi_imx->clk_ipg);
1707 if (ret)
1708 goto out_put_per;
1709
1710 spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1711 /*
1712 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1713 * if validated on other chips.
1714 */
1715 if (spi_imx->devtype_data->has_dmamode) {
1716 ret = spi_imx_sdma_init(&pdev->dev, spi_imx, master);
1717 if (ret == -EPROBE_DEFER)
1718 goto out_clk_put;
1719
1720 if (ret < 0)
1721 dev_err(&pdev->dev, "dma setup error %d, use pio\n",
1722 ret);
1723 }
1724
1725 spi_imx->devtype_data->reset(spi_imx);
1726
1727 spi_imx->devtype_data->intctrl(spi_imx, 0);
1728
1729 master->dev.of_node = pdev->dev.of_node;
1730 ret = spi_bitbang_start(&spi_imx->bitbang);
1731 if (ret) {
1732 dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
1733 goto out_clk_put;
1734 }
1735
1736 /* Request GPIO CS lines, if any */
1737 if (!spi_imx->slave_mode && master->cs_gpios) {
1738 for (i = 0; i < master->num_chipselect; i++) {
1739 if (!gpio_is_valid(master->cs_gpios[i]))
1740 continue;
1741
1742 ret = devm_gpio_request(&pdev->dev,
1743 master->cs_gpios[i],
1744 DRIVER_NAME);
1745 if (ret) {
1746 dev_err(&pdev->dev, "Can't get CS GPIO %i\n",
1747 master->cs_gpios[i]);
1748 goto out_spi_bitbang;
1749 }
1750 }
1751 }
1752
1753 dev_info(&pdev->dev, "probed\n");
1754
1755 clk_disable(spi_imx->clk_ipg);
1756 clk_disable(spi_imx->clk_per);
1757 return ret;
1758
1759 out_spi_bitbang:
1760 spi_bitbang_stop(&spi_imx->bitbang);
1761 out_clk_put:
1762 clk_disable_unprepare(spi_imx->clk_ipg);
1763 out_put_per:
1764 clk_disable_unprepare(spi_imx->clk_per);
1765 out_master_put:
1766 spi_master_put(master);
1767
1768 return ret;
1769 }
1770
spi_imx_remove(struct platform_device * pdev)1771 static int spi_imx_remove(struct platform_device *pdev)
1772 {
1773 struct spi_master *master = platform_get_drvdata(pdev);
1774 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1775 int ret;
1776
1777 spi_bitbang_stop(&spi_imx->bitbang);
1778
1779 ret = clk_enable(spi_imx->clk_per);
1780 if (ret)
1781 return ret;
1782
1783 ret = clk_enable(spi_imx->clk_ipg);
1784 if (ret) {
1785 clk_disable(spi_imx->clk_per);
1786 return ret;
1787 }
1788
1789 writel(0, spi_imx->base + MXC_CSPICTRL);
1790 clk_disable_unprepare(spi_imx->clk_ipg);
1791 clk_disable_unprepare(spi_imx->clk_per);
1792 spi_imx_sdma_exit(spi_imx);
1793 spi_master_put(master);
1794
1795 return 0;
1796 }
1797
1798 static struct platform_driver spi_imx_driver = {
1799 .driver = {
1800 .name = DRIVER_NAME,
1801 .of_match_table = spi_imx_dt_ids,
1802 },
1803 .id_table = spi_imx_devtype,
1804 .probe = spi_imx_probe,
1805 .remove = spi_imx_remove,
1806 };
1807 module_platform_driver(spi_imx_driver);
1808
1809 MODULE_DESCRIPTION("SPI Controller driver");
1810 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1811 MODULE_LICENSE("GPL");
1812 MODULE_ALIAS("platform:" DRIVER_NAME);
1813