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/bits.h>
6 #include <linux/bitfield.h>
7 #include <linux/clk.h>
8 #include <linux/completion.h>
9 #include <linux/delay.h>
10 #include <linux/dmaengine.h>
11 #include <linux/dma-mapping.h>
12 #include <linux/err.h>
13 #include <linux/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/irq.h>
16 #include <linux/kernel.h>
17 #include <linux/math.h>
18 #include <linux/math64.h>
19 #include <linux/module.h>
20 #include <linux/overflow.h>
21 #include <linux/pinctrl/consumer.h>
22 #include <linux/platform_device.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/slab.h>
25 #include <linux/spi/spi.h>
26 #include <linux/types.h>
27 #include <linux/of.h>
28 #include <linux/property.h>
29
30 #include <linux/dma/imx-dma.h>
31
32 #define DRIVER_NAME "spi_imx"
33
34 static bool use_dma = true;
35 module_param(use_dma, bool, 0644);
36 MODULE_PARM_DESC(use_dma, "Enable usage of DMA when available (default)");
37
38 /* define polling limits */
39 static unsigned int polling_limit_us = 30;
40 module_param(polling_limit_us, uint, 0664);
41 MODULE_PARM_DESC(polling_limit_us,
42 "time in us to run a transfer in polling mode\n");
43
44 #define MXC_RPM_TIMEOUT 2000 /* 2000ms */
45
46 #define MXC_CSPIRXDATA 0x00
47 #define MXC_CSPITXDATA 0x04
48 #define MXC_CSPICTRL 0x08
49 #define MXC_CSPIINT 0x0c
50 #define MXC_RESET 0x1c
51
52 /* generic defines to abstract from the different register layouts */
53 #define MXC_INT_RR (1 << 0) /* Receive data ready interrupt */
54 #define MXC_INT_TE (1 << 1) /* Transmit FIFO empty interrupt */
55 #define MXC_INT_RDR BIT(4) /* Receive date threshold interrupt */
56
57 /* The maximum bytes that a sdma BD can transfer. */
58 #define MAX_SDMA_BD_BYTES (1 << 15)
59 #define MX51_ECSPI_CTRL_MAX_BURST 512
60 /* The maximum bytes that IMX53_ECSPI can transfer in target mode.*/
61 #define MX53_MAX_TRANSFER_BYTES 512
62
63 enum spi_imx_devtype {
64 IMX1_CSPI,
65 IMX21_CSPI,
66 IMX27_CSPI,
67 IMX31_CSPI,
68 IMX35_CSPI, /* CSPI on all i.mx except above */
69 IMX51_ECSPI, /* ECSPI on i.mx51 */
70 IMX53_ECSPI, /* ECSPI on i.mx53 and later */
71 };
72
73 struct spi_imx_data;
74
75 struct spi_imx_devtype_data {
76 void (*intctrl)(struct spi_imx_data *spi_imx, int enable);
77 int (*prepare_message)(struct spi_imx_data *spi_imx, struct spi_message *msg);
78 int (*prepare_transfer)(struct spi_imx_data *spi_imx, struct spi_device *spi,
79 struct spi_transfer *t);
80 void (*trigger)(struct spi_imx_data *spi_imx);
81 int (*rx_available)(struct spi_imx_data *spi_imx);
82 void (*reset)(struct spi_imx_data *spi_imx);
83 void (*setup_wml)(struct spi_imx_data *spi_imx);
84 void (*disable)(struct spi_imx_data *spi_imx);
85 bool has_dmamode;
86 bool has_targetmode;
87 unsigned int fifo_size;
88 bool dynamic_burst;
89 /*
90 * ERR009165 fixed or not:
91 * https://www.nxp.com/docs/en/errata/IMX6DQCE.pdf
92 */
93 bool tx_glitch_fixed;
94 enum spi_imx_devtype devtype;
95 };
96
97 struct spi_imx_data {
98 struct spi_controller *controller;
99 struct device *dev;
100
101 struct completion xfer_done;
102 void __iomem *base;
103 unsigned long base_phys;
104
105 struct clk *clk_per;
106 struct clk *clk_ipg;
107 unsigned long spi_clk;
108 unsigned int spi_bus_clk;
109
110 unsigned int bits_per_word;
111 unsigned int spi_drctl;
112
113 unsigned int count, remainder;
114 void (*tx)(struct spi_imx_data *spi_imx);
115 void (*rx)(struct spi_imx_data *spi_imx);
116 void *rx_buf;
117 const void *tx_buf;
118 unsigned int txfifo; /* number of words pushed in tx FIFO */
119 unsigned int dynamic_burst;
120 bool rx_only;
121
122 /* Target mode */
123 bool target_mode;
124 bool target_aborted;
125 unsigned int target_burst;
126
127 /* DMA */
128 bool usedma;
129 u32 wml;
130 struct completion dma_rx_completion;
131 struct completion dma_tx_completion;
132
133 const struct spi_imx_devtype_data *devtype_data;
134 };
135
is_imx27_cspi(struct spi_imx_data * d)136 static inline int is_imx27_cspi(struct spi_imx_data *d)
137 {
138 return d->devtype_data->devtype == IMX27_CSPI;
139 }
140
is_imx35_cspi(struct spi_imx_data * d)141 static inline int is_imx35_cspi(struct spi_imx_data *d)
142 {
143 return d->devtype_data->devtype == IMX35_CSPI;
144 }
145
is_imx51_ecspi(struct spi_imx_data * d)146 static inline int is_imx51_ecspi(struct spi_imx_data *d)
147 {
148 return d->devtype_data->devtype == IMX51_ECSPI;
149 }
150
is_imx53_ecspi(struct spi_imx_data * d)151 static inline int is_imx53_ecspi(struct spi_imx_data *d)
152 {
153 return d->devtype_data->devtype == IMX53_ECSPI;
154 }
155
156 #define MXC_SPI_BUF_RX(type) \
157 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx) \
158 { \
159 unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA); \
160 \
161 if (spi_imx->rx_buf) { \
162 *(type *)spi_imx->rx_buf = val; \
163 spi_imx->rx_buf += sizeof(type); \
164 } \
165 \
166 spi_imx->remainder -= sizeof(type); \
167 }
168
169 #define MXC_SPI_BUF_TX(type) \
170 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx) \
171 { \
172 type val = 0; \
173 \
174 if (spi_imx->tx_buf) { \
175 val = *(type *)spi_imx->tx_buf; \
176 spi_imx->tx_buf += sizeof(type); \
177 } \
178 \
179 spi_imx->count -= sizeof(type); \
180 \
181 writel(val, spi_imx->base + MXC_CSPITXDATA); \
182 }
183
184 MXC_SPI_BUF_RX(u8)
185 MXC_SPI_BUF_TX(u8)
186 MXC_SPI_BUF_RX(u16)
187 MXC_SPI_BUF_TX(u16)
188 MXC_SPI_BUF_RX(u32)
189 MXC_SPI_BUF_TX(u32)
190
191 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
192 * (which is currently not the case in this driver)
193 */
194 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
195 256, 384, 512, 768, 1024};
196
197 /* MX21, MX27 */
spi_imx_clkdiv_1(unsigned int fin,unsigned int fspi,unsigned int max,unsigned int * fres)198 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
199 unsigned int fspi, unsigned int max, unsigned int *fres)
200 {
201 int i;
202
203 for (i = 2; i < max; i++)
204 if (fspi * mxc_clkdivs[i] >= fin)
205 break;
206
207 *fres = fin / mxc_clkdivs[i];
208 return i;
209 }
210
211 /* MX1, MX31, MX35, MX51 CSPI */
spi_imx_clkdiv_2(unsigned int fin,unsigned int fspi,unsigned int * fres)212 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
213 unsigned int fspi, unsigned int *fres)
214 {
215 int i, div = 4;
216
217 for (i = 0; i < 7; i++) {
218 if (fspi * div >= fin)
219 goto out;
220 div <<= 1;
221 }
222
223 out:
224 *fres = fin / div;
225 return i;
226 }
227
spi_imx_bytes_per_word(const int bits_per_word)228 static int spi_imx_bytes_per_word(const int bits_per_word)
229 {
230 if (bits_per_word <= 8)
231 return 1;
232 else if (bits_per_word <= 16)
233 return 2;
234 else
235 return 4;
236 }
237
spi_imx_can_dma(struct spi_controller * controller,struct spi_device * spi,struct spi_transfer * transfer)238 static bool spi_imx_can_dma(struct spi_controller *controller, struct spi_device *spi,
239 struct spi_transfer *transfer)
240 {
241 struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
242
243 if (!use_dma || controller->fallback)
244 return false;
245
246 if (!controller->dma_rx)
247 return false;
248
249 if (spi_imx->target_mode)
250 return false;
251
252 if (transfer->len < spi_imx->devtype_data->fifo_size)
253 return false;
254
255 spi_imx->dynamic_burst = 0;
256
257 return true;
258 }
259
260 /*
261 * Note the number of natively supported chip selects for MX51 is 4. Some
262 * devices may have less actual SS pins but the register map supports 4. When
263 * using gpio chip selects the cs values passed into the macros below can go
264 * outside the range 0 - 3. We therefore need to limit the cs value to avoid
265 * corrupting bits outside the allocated locations.
266 *
267 * The simplest way to do this is to just mask the cs bits to 2 bits. This
268 * still allows all 4 native chip selects to work as well as gpio chip selects
269 * (which can use any of the 4 chip select configurations).
270 */
271
272 #define MX51_ECSPI_CTRL 0x08
273 #define MX51_ECSPI_CTRL_ENABLE (1 << 0)
274 #define MX51_ECSPI_CTRL_XCH (1 << 2)
275 #define MX51_ECSPI_CTRL_SMC (1 << 3)
276 #define MX51_ECSPI_CTRL_MODE_MASK (0xf << 4)
277 #define MX51_ECSPI_CTRL_DRCTL(drctl) ((drctl) << 16)
278 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET 8
279 #define MX51_ECSPI_CTRL_PREDIV_OFFSET 12
280 #define MX51_ECSPI_CTRL_CS(cs) ((cs & 3) << 18)
281 #define MX51_ECSPI_CTRL_BL_OFFSET 20
282 #define MX51_ECSPI_CTRL_BL_MASK (0xfff << 20)
283
284 #define MX51_ECSPI_CONFIG 0x0c
285 #define MX51_ECSPI_CONFIG_SCLKPHA(cs) (1 << ((cs & 3) + 0))
286 #define MX51_ECSPI_CONFIG_SCLKPOL(cs) (1 << ((cs & 3) + 4))
287 #define MX51_ECSPI_CONFIG_SBBCTRL(cs) (1 << ((cs & 3) + 8))
288 #define MX51_ECSPI_CONFIG_SSBPOL(cs) (1 << ((cs & 3) + 12))
289 #define MX51_ECSPI_CONFIG_DATACTL(cs) (1 << ((cs & 3) + 16))
290 #define MX51_ECSPI_CONFIG_SCLKCTL(cs) (1 << ((cs & 3) + 20))
291
292 #define MX51_ECSPI_INT 0x10
293 #define MX51_ECSPI_INT_TEEN (1 << 0)
294 #define MX51_ECSPI_INT_RREN (1 << 3)
295 #define MX51_ECSPI_INT_RDREN (1 << 4)
296
297 #define MX51_ECSPI_DMA 0x14
298 #define MX51_ECSPI_DMA_TX_WML(wml) ((wml) & 0x3f)
299 #define MX51_ECSPI_DMA_RX_WML(wml) (((wml) & 0x3f) << 16)
300 #define MX51_ECSPI_DMA_RXT_WML(wml) (((wml) & 0x3f) << 24)
301
302 #define MX51_ECSPI_DMA_TEDEN (1 << 7)
303 #define MX51_ECSPI_DMA_RXDEN (1 << 23)
304 #define MX51_ECSPI_DMA_RXTDEN (1 << 31)
305
306 #define MX51_ECSPI_STAT 0x18
307 #define MX51_ECSPI_STAT_RR (1 << 3)
308
309 #define MX51_ECSPI_PERIOD 0x1c
310 #define MX51_ECSPI_PERIOD_MASK 0x7fff
311 /*
312 * As measured on the i.MX6, the SPI host controller inserts a 4 SPI-Clock
313 * (SCLK) delay after each burst if the PERIOD reg is 0x0. This value will be
314 * called MX51_ECSPI_PERIOD_MIN_DELAY_SCK.
315 *
316 * If the PERIOD register is != 0, the controller inserts a delay of
317 * MX51_ECSPI_PERIOD_MIN_DELAY_SCK + register value + 1 SCLK after each burst.
318 */
319 #define MX51_ECSPI_PERIOD_MIN_DELAY_SCK 4
320
321 #define MX51_ECSPI_TESTREG 0x20
322 #define MX51_ECSPI_TESTREG_LBC BIT(31)
323
spi_imx_buf_rx_swap_u32(struct spi_imx_data * spi_imx)324 static void spi_imx_buf_rx_swap_u32(struct spi_imx_data *spi_imx)
325 {
326 unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA);
327
328 if (spi_imx->rx_buf) {
329 #ifdef __LITTLE_ENDIAN
330 unsigned int bytes_per_word;
331
332 bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
333 if (bytes_per_word == 1)
334 swab32s(&val);
335 else if (bytes_per_word == 2)
336 swahw32s(&val);
337 #endif
338 *(u32 *)spi_imx->rx_buf = val;
339 spi_imx->rx_buf += sizeof(u32);
340 }
341
342 spi_imx->remainder -= sizeof(u32);
343 }
344
spi_imx_buf_rx_swap(struct spi_imx_data * spi_imx)345 static void spi_imx_buf_rx_swap(struct spi_imx_data *spi_imx)
346 {
347 int unaligned;
348 u32 val;
349
350 unaligned = spi_imx->remainder % 4;
351
352 if (!unaligned) {
353 spi_imx_buf_rx_swap_u32(spi_imx);
354 return;
355 }
356
357 if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
358 spi_imx_buf_rx_u16(spi_imx);
359 return;
360 }
361
362 val = readl(spi_imx->base + MXC_CSPIRXDATA);
363
364 while (unaligned--) {
365 if (spi_imx->rx_buf) {
366 *(u8 *)spi_imx->rx_buf = (val >> (8 * unaligned)) & 0xff;
367 spi_imx->rx_buf++;
368 }
369 spi_imx->remainder--;
370 }
371 }
372
spi_imx_buf_tx_swap_u32(struct spi_imx_data * spi_imx)373 static void spi_imx_buf_tx_swap_u32(struct spi_imx_data *spi_imx)
374 {
375 u32 val = 0;
376 #ifdef __LITTLE_ENDIAN
377 unsigned int bytes_per_word;
378 #endif
379
380 if (spi_imx->tx_buf) {
381 val = *(u32 *)spi_imx->tx_buf;
382 spi_imx->tx_buf += sizeof(u32);
383 }
384
385 spi_imx->count -= sizeof(u32);
386 #ifdef __LITTLE_ENDIAN
387 bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
388
389 if (bytes_per_word == 1)
390 swab32s(&val);
391 else if (bytes_per_word == 2)
392 swahw32s(&val);
393 #endif
394 writel(val, spi_imx->base + MXC_CSPITXDATA);
395 }
396
spi_imx_buf_tx_swap(struct spi_imx_data * spi_imx)397 static void spi_imx_buf_tx_swap(struct spi_imx_data *spi_imx)
398 {
399 int unaligned;
400 u32 val = 0;
401
402 unaligned = spi_imx->count % 4;
403
404 if (!unaligned) {
405 spi_imx_buf_tx_swap_u32(spi_imx);
406 return;
407 }
408
409 if (spi_imx_bytes_per_word(spi_imx->bits_per_word) == 2) {
410 spi_imx_buf_tx_u16(spi_imx);
411 return;
412 }
413
414 while (unaligned--) {
415 if (spi_imx->tx_buf) {
416 val |= *(u8 *)spi_imx->tx_buf << (8 * unaligned);
417 spi_imx->tx_buf++;
418 }
419 spi_imx->count--;
420 }
421
422 writel(val, spi_imx->base + MXC_CSPITXDATA);
423 }
424
mx53_ecspi_rx_target(struct spi_imx_data * spi_imx)425 static void mx53_ecspi_rx_target(struct spi_imx_data *spi_imx)
426 {
427 u32 val = ioread32be(spi_imx->base + MXC_CSPIRXDATA);
428
429 if (spi_imx->rx_buf) {
430 int n_bytes = spi_imx->target_burst % sizeof(val);
431
432 if (!n_bytes)
433 n_bytes = sizeof(val);
434
435 memcpy(spi_imx->rx_buf,
436 ((u8 *)&val) + sizeof(val) - n_bytes, n_bytes);
437
438 spi_imx->rx_buf += n_bytes;
439 spi_imx->target_burst -= n_bytes;
440 }
441
442 spi_imx->remainder -= sizeof(u32);
443 }
444
mx53_ecspi_tx_target(struct spi_imx_data * spi_imx)445 static void mx53_ecspi_tx_target(struct spi_imx_data *spi_imx)
446 {
447 u32 val = 0;
448 int n_bytes = spi_imx->count % sizeof(val);
449
450 if (!n_bytes)
451 n_bytes = sizeof(val);
452
453 if (spi_imx->tx_buf) {
454 memcpy(((u8 *)&val) + sizeof(val) - n_bytes,
455 spi_imx->tx_buf, n_bytes);
456 spi_imx->tx_buf += n_bytes;
457 }
458
459 spi_imx->count -= n_bytes;
460
461 iowrite32be(val, spi_imx->base + MXC_CSPITXDATA);
462 }
463
464 /* MX51 eCSPI */
mx51_ecspi_clkdiv(struct spi_imx_data * spi_imx,unsigned int fspi,unsigned int * fres)465 static unsigned int mx51_ecspi_clkdiv(struct spi_imx_data *spi_imx,
466 unsigned int fspi, unsigned int *fres)
467 {
468 /*
469 * there are two 4-bit dividers, the pre-divider divides by
470 * $pre, the post-divider by 2^$post
471 */
472 unsigned int pre, post;
473 unsigned int fin = spi_imx->spi_clk;
474
475 fspi = min(fspi, fin);
476
477 post = fls(fin) - fls(fspi);
478 if (fin > fspi << post)
479 post++;
480
481 /* now we have: (fin <= fspi << post) with post being minimal */
482
483 post = max(4U, post) - 4;
484 if (unlikely(post > 0xf)) {
485 dev_err(spi_imx->dev, "cannot set clock freq: %u (base freq: %u)\n",
486 fspi, fin);
487 return 0xff;
488 }
489
490 pre = DIV_ROUND_UP(fin, fspi << post) - 1;
491
492 dev_dbg(spi_imx->dev, "%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
493 __func__, fin, fspi, post, pre);
494
495 /* Resulting frequency for the SCLK line. */
496 *fres = (fin / (pre + 1)) >> post;
497
498 return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
499 (post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
500 }
501
mx51_ecspi_intctrl(struct spi_imx_data * spi_imx,int enable)502 static void mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
503 {
504 unsigned int val = 0;
505
506 if (enable & MXC_INT_TE)
507 val |= MX51_ECSPI_INT_TEEN;
508
509 if (enable & MXC_INT_RR)
510 val |= MX51_ECSPI_INT_RREN;
511
512 if (enable & MXC_INT_RDR)
513 val |= MX51_ECSPI_INT_RDREN;
514
515 writel(val, spi_imx->base + MX51_ECSPI_INT);
516 }
517
mx51_ecspi_trigger(struct spi_imx_data * spi_imx)518 static void mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
519 {
520 u32 reg;
521
522 if (spi_imx->usedma) {
523 reg = readl(spi_imx->base + MX51_ECSPI_DMA);
524 reg |= MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN;
525 writel(reg, spi_imx->base + MX51_ECSPI_DMA);
526 } else {
527 reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
528 reg |= MX51_ECSPI_CTRL_XCH;
529 writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
530 }
531 }
532
mx51_ecspi_disable(struct spi_imx_data * spi_imx)533 static void mx51_ecspi_disable(struct spi_imx_data *spi_imx)
534 {
535 u32 ctrl;
536
537 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
538 ctrl &= ~MX51_ECSPI_CTRL_ENABLE;
539 writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
540 }
541
mx51_ecspi_channel(const struct spi_device * spi)542 static int mx51_ecspi_channel(const struct spi_device *spi)
543 {
544 if (!spi_get_csgpiod(spi, 0))
545 return spi_get_chipselect(spi, 0);
546 return spi->controller->unused_native_cs;
547 }
548
mx51_ecspi_prepare_message(struct spi_imx_data * spi_imx,struct spi_message * msg)549 static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
550 struct spi_message *msg)
551 {
552 struct spi_device *spi = msg->spi;
553 struct spi_transfer *xfer;
554 u32 ctrl = MX51_ECSPI_CTRL_ENABLE;
555 u32 min_speed_hz = ~0U;
556 u32 testreg, delay;
557 u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
558 u32 current_cfg = cfg;
559 int channel = mx51_ecspi_channel(spi);
560
561 /* set Host or Target mode */
562 if (spi_imx->target_mode)
563 ctrl &= ~MX51_ECSPI_CTRL_MODE_MASK;
564 else
565 ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
566
567 /*
568 * Enable SPI_RDY handling (falling edge/level triggered).
569 */
570 if (spi->mode & SPI_READY)
571 ctrl |= MX51_ECSPI_CTRL_DRCTL(spi_imx->spi_drctl);
572
573 /* set chip select to use */
574 ctrl |= MX51_ECSPI_CTRL_CS(channel);
575
576 /*
577 * The ctrl register must be written first, with the EN bit set other
578 * registers must not be written to.
579 */
580 writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
581
582 testreg = readl(spi_imx->base + MX51_ECSPI_TESTREG);
583 if (spi->mode & SPI_LOOP)
584 testreg |= MX51_ECSPI_TESTREG_LBC;
585 else
586 testreg &= ~MX51_ECSPI_TESTREG_LBC;
587 writel(testreg, spi_imx->base + MX51_ECSPI_TESTREG);
588
589 /*
590 * eCSPI burst completion by Chip Select signal in Target mode
591 * is not functional for imx53 Soc, config SPI burst completed when
592 * BURST_LENGTH + 1 bits are received
593 */
594 if (spi_imx->target_mode && is_imx53_ecspi(spi_imx))
595 cfg &= ~MX51_ECSPI_CONFIG_SBBCTRL(channel);
596 else
597 cfg |= MX51_ECSPI_CONFIG_SBBCTRL(channel);
598
599 if (spi->mode & SPI_CPOL) {
600 cfg |= MX51_ECSPI_CONFIG_SCLKPOL(channel);
601 cfg |= MX51_ECSPI_CONFIG_SCLKCTL(channel);
602 } else {
603 cfg &= ~MX51_ECSPI_CONFIG_SCLKPOL(channel);
604 cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(channel);
605 }
606
607 if (spi->mode & SPI_MOSI_IDLE_LOW)
608 cfg |= MX51_ECSPI_CONFIG_DATACTL(channel);
609 else
610 cfg &= ~MX51_ECSPI_CONFIG_DATACTL(channel);
611
612 if (spi->mode & SPI_CS_HIGH)
613 cfg |= MX51_ECSPI_CONFIG_SSBPOL(channel);
614 else
615 cfg &= ~MX51_ECSPI_CONFIG_SSBPOL(channel);
616
617 if (cfg == current_cfg)
618 return 0;
619
620 writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
621
622 /*
623 * Wait until the changes in the configuration register CONFIGREG
624 * propagate into the hardware. It takes exactly one tick of the
625 * SCLK clock, but we will wait two SCLK clock just to be sure. The
626 * effect of the delay it takes for the hardware to apply changes
627 * is noticable if the SCLK clock run very slow. In such a case, if
628 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
629 * be asserted before the SCLK polarity changes, which would disrupt
630 * the SPI communication as the device on the other end would consider
631 * the change of SCLK polarity as a clock tick already.
632 *
633 * Because spi_imx->spi_bus_clk is only set in prepare_message
634 * callback, iterate over all the transfers in spi_message, find the
635 * one with lowest bus frequency, and use that bus frequency for the
636 * delay calculation. In case all transfers have speed_hz == 0, then
637 * min_speed_hz is ~0 and the resulting delay is zero.
638 */
639 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
640 if (!xfer->speed_hz)
641 continue;
642 min_speed_hz = min(xfer->speed_hz, min_speed_hz);
643 }
644
645 delay = (2 * 1000000) / min_speed_hz;
646 if (likely(delay < 10)) /* SCLK is faster than 200 kHz */
647 udelay(delay);
648 else /* SCLK is _very_ slow */
649 usleep_range(delay, delay + 10);
650
651 return 0;
652 }
653
mx51_configure_cpha(struct spi_imx_data * spi_imx,struct spi_device * spi)654 static void mx51_configure_cpha(struct spi_imx_data *spi_imx,
655 struct spi_device *spi)
656 {
657 bool cpha = (spi->mode & SPI_CPHA);
658 bool flip_cpha = (spi->mode & SPI_RX_CPHA_FLIP) && spi_imx->rx_only;
659 u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
660 int channel = mx51_ecspi_channel(spi);
661
662 /* Flip cpha logical value iff flip_cpha */
663 cpha ^= flip_cpha;
664
665 if (cpha)
666 cfg |= MX51_ECSPI_CONFIG_SCLKPHA(channel);
667 else
668 cfg &= ~MX51_ECSPI_CONFIG_SCLKPHA(channel);
669
670 writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
671 }
672
mx51_ecspi_prepare_transfer(struct spi_imx_data * spi_imx,struct spi_device * spi,struct spi_transfer * t)673 static int mx51_ecspi_prepare_transfer(struct spi_imx_data *spi_imx,
674 struct spi_device *spi, struct spi_transfer *t)
675 {
676 u32 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
677 u64 word_delay_sck;
678 u32 clk;
679
680 /* Clear BL field and set the right value */
681 ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
682 if (spi_imx->target_mode && is_imx53_ecspi(spi_imx))
683 ctrl |= (spi_imx->target_burst * 8 - 1)
684 << MX51_ECSPI_CTRL_BL_OFFSET;
685 else {
686 ctrl |= (spi_imx->bits_per_word - 1)
687 << MX51_ECSPI_CTRL_BL_OFFSET;
688 }
689
690 /* set clock speed */
691 ctrl &= ~(0xf << MX51_ECSPI_CTRL_POSTDIV_OFFSET |
692 0xf << MX51_ECSPI_CTRL_PREDIV_OFFSET);
693 ctrl |= mx51_ecspi_clkdiv(spi_imx, spi_imx->spi_bus_clk, &clk);
694 spi_imx->spi_bus_clk = clk;
695
696 mx51_configure_cpha(spi_imx, spi);
697
698 /*
699 * ERR009165: work in XHC mode instead of SMC as PIO on the chips
700 * before i.mx6ul.
701 */
702 if (spi_imx->usedma && spi_imx->devtype_data->tx_glitch_fixed)
703 ctrl |= MX51_ECSPI_CTRL_SMC;
704 else
705 ctrl &= ~MX51_ECSPI_CTRL_SMC;
706
707 writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
708
709 /* calculate word delay in SPI Clock (SCLK) cycles */
710 if (t->word_delay.value == 0) {
711 word_delay_sck = 0;
712 } else if (t->word_delay.unit == SPI_DELAY_UNIT_SCK) {
713 word_delay_sck = t->word_delay.value;
714
715 if (word_delay_sck <= MX51_ECSPI_PERIOD_MIN_DELAY_SCK)
716 word_delay_sck = 0;
717 else if (word_delay_sck <= MX51_ECSPI_PERIOD_MIN_DELAY_SCK + 1)
718 word_delay_sck = 1;
719 else
720 word_delay_sck -= MX51_ECSPI_PERIOD_MIN_DELAY_SCK + 1;
721 } else {
722 int word_delay_ns;
723
724 word_delay_ns = spi_delay_to_ns(&t->word_delay, t);
725 if (word_delay_ns < 0)
726 return word_delay_ns;
727
728 if (word_delay_ns <= mul_u64_u32_div(NSEC_PER_SEC,
729 MX51_ECSPI_PERIOD_MIN_DELAY_SCK,
730 spi_imx->spi_bus_clk)) {
731 word_delay_sck = 0;
732 } else if (word_delay_ns <= mul_u64_u32_div(NSEC_PER_SEC,
733 MX51_ECSPI_PERIOD_MIN_DELAY_SCK + 1,
734 spi_imx->spi_bus_clk)) {
735 word_delay_sck = 1;
736 } else {
737 word_delay_ns -= mul_u64_u32_div(NSEC_PER_SEC,
738 MX51_ECSPI_PERIOD_MIN_DELAY_SCK + 1,
739 spi_imx->spi_bus_clk);
740
741 word_delay_sck = DIV_U64_ROUND_UP((u64)word_delay_ns * spi_imx->spi_bus_clk,
742 NSEC_PER_SEC);
743 }
744 }
745
746 if (!FIELD_FIT(MX51_ECSPI_PERIOD_MASK, word_delay_sck))
747 return -EINVAL;
748
749 writel(FIELD_PREP(MX51_ECSPI_PERIOD_MASK, word_delay_sck),
750 spi_imx->base + MX51_ECSPI_PERIOD);
751
752 return 0;
753 }
754
mx51_setup_wml(struct spi_imx_data * spi_imx)755 static void mx51_setup_wml(struct spi_imx_data *spi_imx)
756 {
757 u32 tx_wml = 0;
758
759 if (spi_imx->devtype_data->tx_glitch_fixed)
760 tx_wml = spi_imx->wml;
761 /*
762 * Configure the DMA register: setup the watermark
763 * and enable DMA request.
764 */
765 writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) |
766 MX51_ECSPI_DMA_TX_WML(tx_wml) |
767 MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) |
768 MX51_ECSPI_DMA_RXTDEN, spi_imx->base + MX51_ECSPI_DMA);
769 }
770
mx51_ecspi_rx_available(struct spi_imx_data * spi_imx)771 static int mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
772 {
773 return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
774 }
775
mx51_ecspi_reset(struct spi_imx_data * spi_imx)776 static void mx51_ecspi_reset(struct spi_imx_data *spi_imx)
777 {
778 /* drain receive buffer */
779 while (mx51_ecspi_rx_available(spi_imx))
780 readl(spi_imx->base + MXC_CSPIRXDATA);
781 }
782
783 #define MX31_INTREG_TEEN (1 << 0)
784 #define MX31_INTREG_RREN (1 << 3)
785
786 #define MX31_CSPICTRL_ENABLE (1 << 0)
787 #define MX31_CSPICTRL_HOST (1 << 1)
788 #define MX31_CSPICTRL_XCH (1 << 2)
789 #define MX31_CSPICTRL_SMC (1 << 3)
790 #define MX31_CSPICTRL_POL (1 << 4)
791 #define MX31_CSPICTRL_PHA (1 << 5)
792 #define MX31_CSPICTRL_SSCTL (1 << 6)
793 #define MX31_CSPICTRL_SSPOL (1 << 7)
794 #define MX31_CSPICTRL_BC_SHIFT 8
795 #define MX35_CSPICTRL_BL_SHIFT 20
796 #define MX31_CSPICTRL_CS_SHIFT 24
797 #define MX35_CSPICTRL_CS_SHIFT 12
798 #define MX31_CSPICTRL_DR_SHIFT 16
799
800 #define MX31_CSPI_DMAREG 0x10
801 #define MX31_DMAREG_RH_DEN (1<<4)
802 #define MX31_DMAREG_TH_DEN (1<<1)
803
804 #define MX31_CSPISTATUS 0x14
805 #define MX31_STATUS_RR (1 << 3)
806
807 #define MX31_CSPI_TESTREG 0x1C
808 #define MX31_TEST_LBC (1 << 14)
809
810 /* These functions also work for the i.MX35, but be aware that
811 * the i.MX35 has a slightly different register layout for bits
812 * we do not use here.
813 */
mx31_intctrl(struct spi_imx_data * spi_imx,int enable)814 static void mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
815 {
816 unsigned int val = 0;
817
818 if (enable & MXC_INT_TE)
819 val |= MX31_INTREG_TEEN;
820 if (enable & MXC_INT_RR)
821 val |= MX31_INTREG_RREN;
822
823 writel(val, spi_imx->base + MXC_CSPIINT);
824 }
825
mx31_trigger(struct spi_imx_data * spi_imx)826 static void mx31_trigger(struct spi_imx_data *spi_imx)
827 {
828 unsigned int reg;
829
830 reg = readl(spi_imx->base + MXC_CSPICTRL);
831 reg |= MX31_CSPICTRL_XCH;
832 writel(reg, spi_imx->base + MXC_CSPICTRL);
833 }
834
mx31_prepare_message(struct spi_imx_data * spi_imx,struct spi_message * msg)835 static int mx31_prepare_message(struct spi_imx_data *spi_imx,
836 struct spi_message *msg)
837 {
838 return 0;
839 }
840
mx31_prepare_transfer(struct spi_imx_data * spi_imx,struct spi_device * spi,struct spi_transfer * t)841 static int mx31_prepare_transfer(struct spi_imx_data *spi_imx,
842 struct spi_device *spi, struct spi_transfer *t)
843 {
844 unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_HOST;
845 unsigned int clk;
846
847 reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
848 MX31_CSPICTRL_DR_SHIFT;
849 spi_imx->spi_bus_clk = clk;
850
851 if (is_imx35_cspi(spi_imx)) {
852 reg |= (spi_imx->bits_per_word - 1) << MX35_CSPICTRL_BL_SHIFT;
853 reg |= MX31_CSPICTRL_SSCTL;
854 } else {
855 reg |= (spi_imx->bits_per_word - 1) << MX31_CSPICTRL_BC_SHIFT;
856 }
857
858 if (spi->mode & SPI_CPHA)
859 reg |= MX31_CSPICTRL_PHA;
860 if (spi->mode & SPI_CPOL)
861 reg |= MX31_CSPICTRL_POL;
862 if (spi->mode & SPI_CS_HIGH)
863 reg |= MX31_CSPICTRL_SSPOL;
864 if (!spi_get_csgpiod(spi, 0))
865 reg |= (spi_get_chipselect(spi, 0)) <<
866 (is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
867 MX31_CSPICTRL_CS_SHIFT);
868
869 if (spi_imx->usedma)
870 reg |= MX31_CSPICTRL_SMC;
871
872 writel(reg, spi_imx->base + MXC_CSPICTRL);
873
874 reg = readl(spi_imx->base + MX31_CSPI_TESTREG);
875 if (spi->mode & SPI_LOOP)
876 reg |= MX31_TEST_LBC;
877 else
878 reg &= ~MX31_TEST_LBC;
879 writel(reg, spi_imx->base + MX31_CSPI_TESTREG);
880
881 if (spi_imx->usedma) {
882 /*
883 * configure DMA requests when RXFIFO is half full and
884 * when TXFIFO is half empty
885 */
886 writel(MX31_DMAREG_RH_DEN | MX31_DMAREG_TH_DEN,
887 spi_imx->base + MX31_CSPI_DMAREG);
888 }
889
890 return 0;
891 }
892
mx31_rx_available(struct spi_imx_data * spi_imx)893 static int mx31_rx_available(struct spi_imx_data *spi_imx)
894 {
895 return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
896 }
897
mx31_reset(struct spi_imx_data * spi_imx)898 static void mx31_reset(struct spi_imx_data *spi_imx)
899 {
900 /* drain receive buffer */
901 while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
902 readl(spi_imx->base + MXC_CSPIRXDATA);
903 }
904
905 #define MX21_INTREG_RR (1 << 4)
906 #define MX21_INTREG_TEEN (1 << 9)
907 #define MX21_INTREG_RREN (1 << 13)
908
909 #define MX21_CSPICTRL_POL (1 << 5)
910 #define MX21_CSPICTRL_PHA (1 << 6)
911 #define MX21_CSPICTRL_SSPOL (1 << 8)
912 #define MX21_CSPICTRL_XCH (1 << 9)
913 #define MX21_CSPICTRL_ENABLE (1 << 10)
914 #define MX21_CSPICTRL_HOST (1 << 11)
915 #define MX21_CSPICTRL_DR_SHIFT 14
916 #define MX21_CSPICTRL_CS_SHIFT 19
917
mx21_intctrl(struct spi_imx_data * spi_imx,int enable)918 static void mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
919 {
920 unsigned int val = 0;
921
922 if (enable & MXC_INT_TE)
923 val |= MX21_INTREG_TEEN;
924 if (enable & MXC_INT_RR)
925 val |= MX21_INTREG_RREN;
926
927 writel(val, spi_imx->base + MXC_CSPIINT);
928 }
929
mx21_trigger(struct spi_imx_data * spi_imx)930 static void mx21_trigger(struct spi_imx_data *spi_imx)
931 {
932 unsigned int reg;
933
934 reg = readl(spi_imx->base + MXC_CSPICTRL);
935 reg |= MX21_CSPICTRL_XCH;
936 writel(reg, spi_imx->base + MXC_CSPICTRL);
937 }
938
mx21_prepare_message(struct spi_imx_data * spi_imx,struct spi_message * msg)939 static int mx21_prepare_message(struct spi_imx_data *spi_imx,
940 struct spi_message *msg)
941 {
942 return 0;
943 }
944
mx21_prepare_transfer(struct spi_imx_data * spi_imx,struct spi_device * spi,struct spi_transfer * t)945 static int mx21_prepare_transfer(struct spi_imx_data *spi_imx,
946 struct spi_device *spi, struct spi_transfer *t)
947 {
948 unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_HOST;
949 unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
950 unsigned int clk;
951
952 reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, spi_imx->spi_bus_clk, max, &clk)
953 << MX21_CSPICTRL_DR_SHIFT;
954 spi_imx->spi_bus_clk = clk;
955
956 reg |= spi_imx->bits_per_word - 1;
957
958 if (spi->mode & SPI_CPHA)
959 reg |= MX21_CSPICTRL_PHA;
960 if (spi->mode & SPI_CPOL)
961 reg |= MX21_CSPICTRL_POL;
962 if (spi->mode & SPI_CS_HIGH)
963 reg |= MX21_CSPICTRL_SSPOL;
964 if (!spi_get_csgpiod(spi, 0))
965 reg |= spi_get_chipselect(spi, 0) << MX21_CSPICTRL_CS_SHIFT;
966
967 writel(reg, spi_imx->base + MXC_CSPICTRL);
968
969 return 0;
970 }
971
mx21_rx_available(struct spi_imx_data * spi_imx)972 static int mx21_rx_available(struct spi_imx_data *spi_imx)
973 {
974 return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
975 }
976
mx21_reset(struct spi_imx_data * spi_imx)977 static void mx21_reset(struct spi_imx_data *spi_imx)
978 {
979 writel(1, spi_imx->base + MXC_RESET);
980 }
981
982 #define MX1_INTREG_RR (1 << 3)
983 #define MX1_INTREG_TEEN (1 << 8)
984 #define MX1_INTREG_RREN (1 << 11)
985
986 #define MX1_CSPICTRL_POL (1 << 4)
987 #define MX1_CSPICTRL_PHA (1 << 5)
988 #define MX1_CSPICTRL_XCH (1 << 8)
989 #define MX1_CSPICTRL_ENABLE (1 << 9)
990 #define MX1_CSPICTRL_HOST (1 << 10)
991 #define MX1_CSPICTRL_DR_SHIFT 13
992
mx1_intctrl(struct spi_imx_data * spi_imx,int enable)993 static void mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
994 {
995 unsigned int val = 0;
996
997 if (enable & MXC_INT_TE)
998 val |= MX1_INTREG_TEEN;
999 if (enable & MXC_INT_RR)
1000 val |= MX1_INTREG_RREN;
1001
1002 writel(val, spi_imx->base + MXC_CSPIINT);
1003 }
1004
mx1_trigger(struct spi_imx_data * spi_imx)1005 static void mx1_trigger(struct spi_imx_data *spi_imx)
1006 {
1007 unsigned int reg;
1008
1009 reg = readl(spi_imx->base + MXC_CSPICTRL);
1010 reg |= MX1_CSPICTRL_XCH;
1011 writel(reg, spi_imx->base + MXC_CSPICTRL);
1012 }
1013
mx1_prepare_message(struct spi_imx_data * spi_imx,struct spi_message * msg)1014 static int mx1_prepare_message(struct spi_imx_data *spi_imx,
1015 struct spi_message *msg)
1016 {
1017 return 0;
1018 }
1019
mx1_prepare_transfer(struct spi_imx_data * spi_imx,struct spi_device * spi,struct spi_transfer * t)1020 static int mx1_prepare_transfer(struct spi_imx_data *spi_imx,
1021 struct spi_device *spi, struct spi_transfer *t)
1022 {
1023 unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_HOST;
1024 unsigned int clk;
1025
1026 reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, spi_imx->spi_bus_clk, &clk) <<
1027 MX1_CSPICTRL_DR_SHIFT;
1028 spi_imx->spi_bus_clk = clk;
1029
1030 reg |= spi_imx->bits_per_word - 1;
1031
1032 if (spi->mode & SPI_CPHA)
1033 reg |= MX1_CSPICTRL_PHA;
1034 if (spi->mode & SPI_CPOL)
1035 reg |= MX1_CSPICTRL_POL;
1036
1037 writel(reg, spi_imx->base + MXC_CSPICTRL);
1038
1039 return 0;
1040 }
1041
mx1_rx_available(struct spi_imx_data * spi_imx)1042 static int mx1_rx_available(struct spi_imx_data *spi_imx)
1043 {
1044 return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
1045 }
1046
mx1_reset(struct spi_imx_data * spi_imx)1047 static void mx1_reset(struct spi_imx_data *spi_imx)
1048 {
1049 writel(1, spi_imx->base + MXC_RESET);
1050 }
1051
1052 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
1053 .intctrl = mx1_intctrl,
1054 .prepare_message = mx1_prepare_message,
1055 .prepare_transfer = mx1_prepare_transfer,
1056 .trigger = mx1_trigger,
1057 .rx_available = mx1_rx_available,
1058 .reset = mx1_reset,
1059 .fifo_size = 8,
1060 .has_dmamode = false,
1061 .dynamic_burst = false,
1062 .has_targetmode = false,
1063 .devtype = IMX1_CSPI,
1064 };
1065
1066 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
1067 .intctrl = mx21_intctrl,
1068 .prepare_message = mx21_prepare_message,
1069 .prepare_transfer = mx21_prepare_transfer,
1070 .trigger = mx21_trigger,
1071 .rx_available = mx21_rx_available,
1072 .reset = mx21_reset,
1073 .fifo_size = 8,
1074 .has_dmamode = false,
1075 .dynamic_burst = false,
1076 .has_targetmode = false,
1077 .devtype = IMX21_CSPI,
1078 };
1079
1080 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
1081 /* i.mx27 cspi shares the functions with i.mx21 one */
1082 .intctrl = mx21_intctrl,
1083 .prepare_message = mx21_prepare_message,
1084 .prepare_transfer = mx21_prepare_transfer,
1085 .trigger = mx21_trigger,
1086 .rx_available = mx21_rx_available,
1087 .reset = mx21_reset,
1088 .fifo_size = 8,
1089 .has_dmamode = false,
1090 .dynamic_burst = false,
1091 .has_targetmode = false,
1092 .devtype = IMX27_CSPI,
1093 };
1094
1095 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
1096 .intctrl = mx31_intctrl,
1097 .prepare_message = mx31_prepare_message,
1098 .prepare_transfer = mx31_prepare_transfer,
1099 .trigger = mx31_trigger,
1100 .rx_available = mx31_rx_available,
1101 .reset = mx31_reset,
1102 .fifo_size = 8,
1103 .has_dmamode = false,
1104 .dynamic_burst = false,
1105 .has_targetmode = false,
1106 .devtype = IMX31_CSPI,
1107 };
1108
1109 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
1110 /* i.mx35 and later cspi shares the functions with i.mx31 one */
1111 .intctrl = mx31_intctrl,
1112 .prepare_message = mx31_prepare_message,
1113 .prepare_transfer = mx31_prepare_transfer,
1114 .trigger = mx31_trigger,
1115 .rx_available = mx31_rx_available,
1116 .reset = mx31_reset,
1117 .fifo_size = 8,
1118 .has_dmamode = false,
1119 .dynamic_burst = false,
1120 .has_targetmode = false,
1121 .devtype = IMX35_CSPI,
1122 };
1123
1124 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
1125 .intctrl = mx51_ecspi_intctrl,
1126 .prepare_message = mx51_ecspi_prepare_message,
1127 .prepare_transfer = mx51_ecspi_prepare_transfer,
1128 .trigger = mx51_ecspi_trigger,
1129 .rx_available = mx51_ecspi_rx_available,
1130 .reset = mx51_ecspi_reset,
1131 .setup_wml = mx51_setup_wml,
1132 .fifo_size = 64,
1133 .has_dmamode = true,
1134 .dynamic_burst = true,
1135 .has_targetmode = true,
1136 .disable = mx51_ecspi_disable,
1137 .devtype = IMX51_ECSPI,
1138 };
1139
1140 static struct spi_imx_devtype_data imx53_ecspi_devtype_data = {
1141 .intctrl = mx51_ecspi_intctrl,
1142 .prepare_message = mx51_ecspi_prepare_message,
1143 .prepare_transfer = mx51_ecspi_prepare_transfer,
1144 .trigger = mx51_ecspi_trigger,
1145 .rx_available = mx51_ecspi_rx_available,
1146 .reset = mx51_ecspi_reset,
1147 .fifo_size = 64,
1148 .has_dmamode = true,
1149 .has_targetmode = true,
1150 .disable = mx51_ecspi_disable,
1151 .devtype = IMX53_ECSPI,
1152 };
1153
1154 static struct spi_imx_devtype_data imx6ul_ecspi_devtype_data = {
1155 .intctrl = mx51_ecspi_intctrl,
1156 .prepare_message = mx51_ecspi_prepare_message,
1157 .prepare_transfer = mx51_ecspi_prepare_transfer,
1158 .trigger = mx51_ecspi_trigger,
1159 .rx_available = mx51_ecspi_rx_available,
1160 .reset = mx51_ecspi_reset,
1161 .setup_wml = mx51_setup_wml,
1162 .fifo_size = 64,
1163 .has_dmamode = true,
1164 .dynamic_burst = true,
1165 .has_targetmode = true,
1166 .tx_glitch_fixed = true,
1167 .disable = mx51_ecspi_disable,
1168 .devtype = IMX51_ECSPI,
1169 };
1170
1171 static const struct of_device_id spi_imx_dt_ids[] = {
1172 { .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
1173 { .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
1174 { .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
1175 { .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
1176 { .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
1177 { .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
1178 { .compatible = "fsl,imx53-ecspi", .data = &imx53_ecspi_devtype_data, },
1179 { .compatible = "fsl,imx6ul-ecspi", .data = &imx6ul_ecspi_devtype_data, },
1180 { /* sentinel */ }
1181 };
1182 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
1183
spi_imx_set_burst_len(struct spi_imx_data * spi_imx,int n_bits)1184 static void spi_imx_set_burst_len(struct spi_imx_data *spi_imx, int n_bits)
1185 {
1186 u32 ctrl;
1187
1188 ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
1189 ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
1190 ctrl |= ((n_bits - 1) << MX51_ECSPI_CTRL_BL_OFFSET);
1191 writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
1192 }
1193
spi_imx_push(struct spi_imx_data * spi_imx)1194 static void spi_imx_push(struct spi_imx_data *spi_imx)
1195 {
1196 unsigned int burst_len;
1197
1198 /*
1199 * Reload the FIFO when the remaining bytes to be transferred in the
1200 * current burst is 0. This only applies when bits_per_word is a
1201 * multiple of 8.
1202 */
1203 if (!spi_imx->remainder) {
1204 if (spi_imx->dynamic_burst) {
1205
1206 /* We need to deal unaligned data first */
1207 burst_len = spi_imx->count % MX51_ECSPI_CTRL_MAX_BURST;
1208
1209 if (!burst_len)
1210 burst_len = MX51_ECSPI_CTRL_MAX_BURST;
1211
1212 spi_imx_set_burst_len(spi_imx, burst_len * 8);
1213
1214 spi_imx->remainder = burst_len;
1215 } else {
1216 spi_imx->remainder = spi_imx_bytes_per_word(spi_imx->bits_per_word);
1217 }
1218 }
1219
1220 while (spi_imx->txfifo < spi_imx->devtype_data->fifo_size) {
1221 if (!spi_imx->count)
1222 break;
1223 if (spi_imx->dynamic_burst &&
1224 spi_imx->txfifo >= DIV_ROUND_UP(spi_imx->remainder, 4))
1225 break;
1226 spi_imx->tx(spi_imx);
1227 spi_imx->txfifo++;
1228 }
1229
1230 if (!spi_imx->target_mode)
1231 spi_imx->devtype_data->trigger(spi_imx);
1232 }
1233
spi_imx_isr(int irq,void * dev_id)1234 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
1235 {
1236 struct spi_imx_data *spi_imx = dev_id;
1237
1238 while (spi_imx->txfifo &&
1239 spi_imx->devtype_data->rx_available(spi_imx)) {
1240 spi_imx->rx(spi_imx);
1241 spi_imx->txfifo--;
1242 }
1243
1244 if (spi_imx->count) {
1245 spi_imx_push(spi_imx);
1246 return IRQ_HANDLED;
1247 }
1248
1249 if (spi_imx->txfifo) {
1250 /* No data left to push, but still waiting for rx data,
1251 * enable receive data available interrupt.
1252 */
1253 spi_imx->devtype_data->intctrl(
1254 spi_imx, MXC_INT_RR);
1255 return IRQ_HANDLED;
1256 }
1257
1258 spi_imx->devtype_data->intctrl(spi_imx, 0);
1259 complete(&spi_imx->xfer_done);
1260
1261 return IRQ_HANDLED;
1262 }
1263
spi_imx_dma_configure(struct spi_controller * controller)1264 static int spi_imx_dma_configure(struct spi_controller *controller)
1265 {
1266 int ret;
1267 enum dma_slave_buswidth buswidth;
1268 struct dma_slave_config rx = {}, tx = {};
1269 struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1270
1271 switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
1272 case 4:
1273 buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
1274 break;
1275 case 2:
1276 buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
1277 break;
1278 case 1:
1279 buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
1280 break;
1281 default:
1282 return -EINVAL;
1283 }
1284
1285 tx.direction = DMA_MEM_TO_DEV;
1286 tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
1287 tx.dst_addr_width = buswidth;
1288 tx.dst_maxburst = spi_imx->wml;
1289 ret = dmaengine_slave_config(controller->dma_tx, &tx);
1290 if (ret) {
1291 dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
1292 return ret;
1293 }
1294
1295 rx.direction = DMA_DEV_TO_MEM;
1296 rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
1297 rx.src_addr_width = buswidth;
1298 rx.src_maxburst = spi_imx->wml;
1299 ret = dmaengine_slave_config(controller->dma_rx, &rx);
1300 if (ret) {
1301 dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
1302 return ret;
1303 }
1304
1305 return 0;
1306 }
1307
spi_imx_setupxfer(struct spi_device * spi,struct spi_transfer * t)1308 static int spi_imx_setupxfer(struct spi_device *spi,
1309 struct spi_transfer *t)
1310 {
1311 struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1312
1313 if (!t)
1314 return 0;
1315
1316 if (!t->speed_hz) {
1317 if (!spi->max_speed_hz) {
1318 dev_err(&spi->dev, "no speed_hz provided!\n");
1319 return -EINVAL;
1320 }
1321 dev_dbg(&spi->dev, "using spi->max_speed_hz!\n");
1322 spi_imx->spi_bus_clk = spi->max_speed_hz;
1323 } else
1324 spi_imx->spi_bus_clk = t->speed_hz;
1325
1326 spi_imx->bits_per_word = t->bits_per_word;
1327 spi_imx->count = t->len;
1328
1329 /*
1330 * Initialize the functions for transfer. To transfer non byte-aligned
1331 * words, we have to use multiple word-size bursts. To insert word
1332 * delay, the burst size has to equal the word size. We can't use
1333 * dynamic_burst in these cases.
1334 */
1335 if (spi_imx->devtype_data->dynamic_burst && !spi_imx->target_mode &&
1336 !(spi->mode & SPI_CS_WORD) &&
1337 !(t->word_delay.value) &&
1338 (spi_imx->bits_per_word == 8 ||
1339 spi_imx->bits_per_word == 16 ||
1340 spi_imx->bits_per_word == 32)) {
1341
1342 spi_imx->rx = spi_imx_buf_rx_swap;
1343 spi_imx->tx = spi_imx_buf_tx_swap;
1344 spi_imx->dynamic_burst = 1;
1345
1346 } else {
1347 if (spi_imx->bits_per_word <= 8) {
1348 spi_imx->rx = spi_imx_buf_rx_u8;
1349 spi_imx->tx = spi_imx_buf_tx_u8;
1350 } else if (spi_imx->bits_per_word <= 16) {
1351 spi_imx->rx = spi_imx_buf_rx_u16;
1352 spi_imx->tx = spi_imx_buf_tx_u16;
1353 } else {
1354 spi_imx->rx = spi_imx_buf_rx_u32;
1355 spi_imx->tx = spi_imx_buf_tx_u32;
1356 }
1357 spi_imx->dynamic_burst = 0;
1358 }
1359
1360 if (spi_imx_can_dma(spi_imx->controller, spi, t))
1361 spi_imx->usedma = true;
1362 else
1363 spi_imx->usedma = false;
1364
1365 spi_imx->rx_only = ((t->tx_buf == NULL)
1366 || (t->tx_buf == spi->controller->dummy_tx));
1367
1368 if (is_imx53_ecspi(spi_imx) && spi_imx->target_mode) {
1369 spi_imx->rx = mx53_ecspi_rx_target;
1370 spi_imx->tx = mx53_ecspi_tx_target;
1371 spi_imx->target_burst = t->len;
1372 }
1373
1374 spi_imx->devtype_data->prepare_transfer(spi_imx, spi, t);
1375
1376 return 0;
1377 }
1378
spi_imx_sdma_exit(struct spi_imx_data * spi_imx)1379 static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
1380 {
1381 struct spi_controller *controller = spi_imx->controller;
1382
1383 if (controller->dma_rx) {
1384 dma_release_channel(controller->dma_rx);
1385 controller->dma_rx = NULL;
1386 }
1387
1388 if (controller->dma_tx) {
1389 dma_release_channel(controller->dma_tx);
1390 controller->dma_tx = NULL;
1391 }
1392 }
1393
spi_imx_sdma_init(struct device * dev,struct spi_imx_data * spi_imx,struct spi_controller * controller)1394 static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
1395 struct spi_controller *controller)
1396 {
1397 int ret;
1398
1399 spi_imx->wml = spi_imx->devtype_data->fifo_size / 2;
1400
1401 /* Prepare for TX DMA: */
1402 controller->dma_tx = dma_request_chan(dev, "tx");
1403 if (IS_ERR(controller->dma_tx)) {
1404 ret = PTR_ERR(controller->dma_tx);
1405 dev_err_probe(dev, ret, "can't get the TX DMA channel!\n");
1406 controller->dma_tx = NULL;
1407 goto err;
1408 }
1409
1410 /* Prepare for RX : */
1411 controller->dma_rx = dma_request_chan(dev, "rx");
1412 if (IS_ERR(controller->dma_rx)) {
1413 ret = PTR_ERR(controller->dma_rx);
1414 dev_err_probe(dev, ret, "can't get the RX DMA channel!\n");
1415 controller->dma_rx = NULL;
1416 goto err;
1417 }
1418
1419 init_completion(&spi_imx->dma_rx_completion);
1420 init_completion(&spi_imx->dma_tx_completion);
1421 controller->can_dma = spi_imx_can_dma;
1422 controller->max_dma_len = MAX_SDMA_BD_BYTES;
1423 spi_imx->controller->flags = SPI_CONTROLLER_MUST_RX |
1424 SPI_CONTROLLER_MUST_TX;
1425
1426 return 0;
1427 err:
1428 spi_imx_sdma_exit(spi_imx);
1429 return ret;
1430 }
1431
spi_imx_dma_rx_callback(void * cookie)1432 static void spi_imx_dma_rx_callback(void *cookie)
1433 {
1434 struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1435
1436 complete(&spi_imx->dma_rx_completion);
1437 }
1438
spi_imx_dma_tx_callback(void * cookie)1439 static void spi_imx_dma_tx_callback(void *cookie)
1440 {
1441 struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
1442
1443 complete(&spi_imx->dma_tx_completion);
1444 }
1445
spi_imx_calculate_timeout(struct spi_imx_data * spi_imx,int size)1446 static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
1447 {
1448 unsigned long timeout = 0;
1449
1450 /* Time with actual data transfer and CS change delay related to HW */
1451 timeout = (8 + 4) * size / spi_imx->spi_bus_clk;
1452
1453 /* Add extra second for scheduler related activities */
1454 timeout += 1;
1455
1456 /* Double calculated timeout */
1457 return secs_to_jiffies(2 * timeout);
1458 }
1459
spi_imx_dma_transfer(struct spi_imx_data * spi_imx,struct spi_transfer * transfer)1460 static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
1461 struct spi_transfer *transfer)
1462 {
1463 struct dma_async_tx_descriptor *desc_tx, *desc_rx;
1464 unsigned long transfer_timeout;
1465 unsigned long time_left;
1466 struct spi_controller *controller = spi_imx->controller;
1467 struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
1468 struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
1469 unsigned int bytes_per_word, i;
1470 int ret;
1471
1472 /* Get the right burst length from the last sg to ensure no tail data */
1473 bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
1474 for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
1475 if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
1476 break;
1477 }
1478 /* Use 1 as wml in case no available burst length got */
1479 if (i == 0)
1480 i = 1;
1481
1482 spi_imx->wml = i;
1483
1484 ret = spi_imx_dma_configure(controller);
1485 if (ret)
1486 goto dma_failure_no_start;
1487
1488 if (!spi_imx->devtype_data->setup_wml) {
1489 dev_err(spi_imx->dev, "No setup_wml()?\n");
1490 ret = -EINVAL;
1491 goto dma_failure_no_start;
1492 }
1493 spi_imx->devtype_data->setup_wml(spi_imx);
1494
1495 /*
1496 * The TX DMA setup starts the transfer, so make sure RX is configured
1497 * before TX.
1498 */
1499 desc_rx = dmaengine_prep_slave_sg(controller->dma_rx,
1500 rx->sgl, rx->nents, DMA_DEV_TO_MEM,
1501 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1502 if (!desc_rx) {
1503 ret = -EINVAL;
1504 goto dma_failure_no_start;
1505 }
1506
1507 desc_rx->callback = spi_imx_dma_rx_callback;
1508 desc_rx->callback_param = (void *)spi_imx;
1509 dmaengine_submit(desc_rx);
1510 reinit_completion(&spi_imx->dma_rx_completion);
1511 dma_async_issue_pending(controller->dma_rx);
1512
1513 desc_tx = dmaengine_prep_slave_sg(controller->dma_tx,
1514 tx->sgl, tx->nents, DMA_MEM_TO_DEV,
1515 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1516 if (!desc_tx) {
1517 dmaengine_terminate_all(controller->dma_tx);
1518 dmaengine_terminate_all(controller->dma_rx);
1519 return -EINVAL;
1520 }
1521
1522 desc_tx->callback = spi_imx_dma_tx_callback;
1523 desc_tx->callback_param = (void *)spi_imx;
1524 dmaengine_submit(desc_tx);
1525 reinit_completion(&spi_imx->dma_tx_completion);
1526 dma_async_issue_pending(controller->dma_tx);
1527
1528 spi_imx->devtype_data->trigger(spi_imx);
1529
1530 transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1531
1532 /* Wait SDMA to finish the data transfer.*/
1533 time_left = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
1534 transfer_timeout);
1535 if (!time_left) {
1536 dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
1537 dmaengine_terminate_all(controller->dma_tx);
1538 dmaengine_terminate_all(controller->dma_rx);
1539 return -ETIMEDOUT;
1540 }
1541
1542 time_left = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
1543 transfer_timeout);
1544 if (!time_left) {
1545 dev_err(&controller->dev, "I/O Error in DMA RX\n");
1546 spi_imx->devtype_data->reset(spi_imx);
1547 dmaengine_terminate_all(controller->dma_rx);
1548 return -ETIMEDOUT;
1549 }
1550
1551 return 0;
1552 /* fallback to pio */
1553 dma_failure_no_start:
1554 transfer->error |= SPI_TRANS_FAIL_NO_START;
1555 return ret;
1556 }
1557
spi_imx_pio_transfer(struct spi_device * spi,struct spi_transfer * transfer)1558 static int spi_imx_pio_transfer(struct spi_device *spi,
1559 struct spi_transfer *transfer)
1560 {
1561 struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1562 unsigned long transfer_timeout;
1563 unsigned long time_left;
1564
1565 spi_imx->tx_buf = transfer->tx_buf;
1566 spi_imx->rx_buf = transfer->rx_buf;
1567 spi_imx->count = transfer->len;
1568 spi_imx->txfifo = 0;
1569 spi_imx->remainder = 0;
1570
1571 reinit_completion(&spi_imx->xfer_done);
1572
1573 spi_imx_push(spi_imx);
1574
1575 spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1576
1577 transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
1578
1579 time_left = wait_for_completion_timeout(&spi_imx->xfer_done,
1580 transfer_timeout);
1581 if (!time_left) {
1582 dev_err(&spi->dev, "I/O Error in PIO\n");
1583 spi_imx->devtype_data->reset(spi_imx);
1584 return -ETIMEDOUT;
1585 }
1586
1587 return 0;
1588 }
1589
spi_imx_poll_transfer(struct spi_device * spi,struct spi_transfer * transfer)1590 static int spi_imx_poll_transfer(struct spi_device *spi,
1591 struct spi_transfer *transfer)
1592 {
1593 struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1594 unsigned long timeout;
1595
1596 spi_imx->tx_buf = transfer->tx_buf;
1597 spi_imx->rx_buf = transfer->rx_buf;
1598 spi_imx->count = transfer->len;
1599 spi_imx->txfifo = 0;
1600 spi_imx->remainder = 0;
1601
1602 /* fill in the fifo before timeout calculations if we are
1603 * interrupted here, then the data is getting transferred by
1604 * the HW while we are interrupted
1605 */
1606 spi_imx_push(spi_imx);
1607
1608 timeout = spi_imx_calculate_timeout(spi_imx, transfer->len) + jiffies;
1609 while (spi_imx->txfifo) {
1610 /* RX */
1611 while (spi_imx->txfifo &&
1612 spi_imx->devtype_data->rx_available(spi_imx)) {
1613 spi_imx->rx(spi_imx);
1614 spi_imx->txfifo--;
1615 }
1616
1617 /* TX */
1618 if (spi_imx->count) {
1619 spi_imx_push(spi_imx);
1620 continue;
1621 }
1622
1623 if (spi_imx->txfifo &&
1624 time_after(jiffies, timeout)) {
1625
1626 dev_err_ratelimited(&spi->dev,
1627 "timeout period reached: jiffies: %lu- falling back to interrupt mode\n",
1628 jiffies - timeout);
1629
1630 /* fall back to interrupt mode */
1631 return spi_imx_pio_transfer(spi, transfer);
1632 }
1633 }
1634
1635 return 0;
1636 }
1637
spi_imx_pio_transfer_target(struct spi_device * spi,struct spi_transfer * transfer)1638 static int spi_imx_pio_transfer_target(struct spi_device *spi,
1639 struct spi_transfer *transfer)
1640 {
1641 struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1642 int ret = 0;
1643
1644 if (is_imx53_ecspi(spi_imx) &&
1645 transfer->len > MX53_MAX_TRANSFER_BYTES) {
1646 dev_err(&spi->dev, "Transaction too big, max size is %d bytes\n",
1647 MX53_MAX_TRANSFER_BYTES);
1648 return -EMSGSIZE;
1649 }
1650
1651 spi_imx->tx_buf = transfer->tx_buf;
1652 spi_imx->rx_buf = transfer->rx_buf;
1653 spi_imx->count = transfer->len;
1654 spi_imx->txfifo = 0;
1655 spi_imx->remainder = 0;
1656
1657 reinit_completion(&spi_imx->xfer_done);
1658 spi_imx->target_aborted = false;
1659
1660 spi_imx_push(spi_imx);
1661
1662 spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE | MXC_INT_RDR);
1663
1664 if (wait_for_completion_interruptible(&spi_imx->xfer_done) ||
1665 spi_imx->target_aborted) {
1666 dev_dbg(&spi->dev, "interrupted\n");
1667 ret = -EINTR;
1668 }
1669
1670 /* ecspi has a HW issue when works in Target mode,
1671 * after 64 words writtern to TXFIFO, even TXFIFO becomes empty,
1672 * ECSPI_TXDATA keeps shift out the last word data,
1673 * so we have to disable ECSPI when in target mode after the
1674 * transfer completes
1675 */
1676 if (spi_imx->devtype_data->disable)
1677 spi_imx->devtype_data->disable(spi_imx);
1678
1679 return ret;
1680 }
1681
spi_imx_transfer_estimate_time_us(struct spi_transfer * transfer)1682 static unsigned int spi_imx_transfer_estimate_time_us(struct spi_transfer *transfer)
1683 {
1684 u64 result;
1685
1686 result = DIV_U64_ROUND_CLOSEST((u64)USEC_PER_SEC * transfer->len * BITS_PER_BYTE,
1687 transfer->effective_speed_hz);
1688 if (transfer->word_delay.value) {
1689 unsigned int word_delay_us;
1690 unsigned int words;
1691
1692 words = DIV_ROUND_UP(transfer->len * BITS_PER_BYTE, transfer->bits_per_word);
1693 word_delay_us = DIV_ROUND_CLOSEST(spi_delay_to_ns(&transfer->word_delay, transfer),
1694 NSEC_PER_USEC);
1695 result += (u64)words * word_delay_us;
1696 }
1697
1698 return min(result, U32_MAX);
1699 }
1700
spi_imx_transfer_one(struct spi_controller * controller,struct spi_device * spi,struct spi_transfer * transfer)1701 static int spi_imx_transfer_one(struct spi_controller *controller,
1702 struct spi_device *spi,
1703 struct spi_transfer *transfer)
1704 {
1705 int ret;
1706 struct spi_imx_data *spi_imx = spi_controller_get_devdata(spi->controller);
1707
1708 ret = spi_imx_setupxfer(spi, transfer);
1709 if (ret < 0)
1710 return ret;
1711 transfer->effective_speed_hz = spi_imx->spi_bus_clk;
1712
1713 /* flush rxfifo before transfer */
1714 while (spi_imx->devtype_data->rx_available(spi_imx))
1715 readl(spi_imx->base + MXC_CSPIRXDATA);
1716
1717 if (spi_imx->target_mode)
1718 return spi_imx_pio_transfer_target(spi, transfer);
1719
1720 /*
1721 * If we decided in spi_imx_can_dma() that we want to do a DMA
1722 * transfer, the SPI transfer has already been mapped, so we
1723 * have to do the DMA transfer here.
1724 */
1725 if (spi_imx->usedma)
1726 return spi_imx_dma_transfer(spi_imx, transfer);
1727
1728 /* run in polling mode for short transfers */
1729 if (transfer->len == 1 || (polling_limit_us &&
1730 spi_imx_transfer_estimate_time_us(transfer) < polling_limit_us))
1731 return spi_imx_poll_transfer(spi, transfer);
1732
1733 return spi_imx_pio_transfer(spi, transfer);
1734 }
1735
spi_imx_setup(struct spi_device * spi)1736 static int spi_imx_setup(struct spi_device *spi)
1737 {
1738 dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1739 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1740
1741 return 0;
1742 }
1743
1744 static int
spi_imx_prepare_message(struct spi_controller * controller,struct spi_message * msg)1745 spi_imx_prepare_message(struct spi_controller *controller, struct spi_message *msg)
1746 {
1747 struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1748 int ret;
1749
1750 ret = pm_runtime_resume_and_get(spi_imx->dev);
1751 if (ret < 0) {
1752 dev_err(spi_imx->dev, "failed to enable clock\n");
1753 return ret;
1754 }
1755
1756 ret = spi_imx->devtype_data->prepare_message(spi_imx, msg);
1757 if (ret) {
1758 pm_runtime_put_autosuspend(spi_imx->dev);
1759 }
1760
1761 return ret;
1762 }
1763
1764 static int
spi_imx_unprepare_message(struct spi_controller * controller,struct spi_message * msg)1765 spi_imx_unprepare_message(struct spi_controller *controller, struct spi_message *msg)
1766 {
1767 struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1768
1769 pm_runtime_put_autosuspend(spi_imx->dev);
1770 return 0;
1771 }
1772
spi_imx_target_abort(struct spi_controller * controller)1773 static int spi_imx_target_abort(struct spi_controller *controller)
1774 {
1775 struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1776
1777 spi_imx->target_aborted = true;
1778 complete(&spi_imx->xfer_done);
1779
1780 return 0;
1781 }
1782
spi_imx_probe(struct platform_device * pdev)1783 static int spi_imx_probe(struct platform_device *pdev)
1784 {
1785 struct device_node *np = pdev->dev.of_node;
1786 struct spi_controller *controller;
1787 struct spi_imx_data *spi_imx;
1788 struct resource *res;
1789 int ret, irq, spi_drctl;
1790 const struct spi_imx_devtype_data *devtype_data =
1791 of_device_get_match_data(&pdev->dev);
1792 bool target_mode;
1793 u32 val;
1794
1795 target_mode = devtype_data->has_targetmode &&
1796 of_property_read_bool(np, "spi-slave");
1797 if (target_mode)
1798 controller = spi_alloc_target(&pdev->dev,
1799 sizeof(struct spi_imx_data));
1800 else
1801 controller = spi_alloc_host(&pdev->dev,
1802 sizeof(struct spi_imx_data));
1803 if (!controller)
1804 return -ENOMEM;
1805
1806 ret = of_property_read_u32(np, "fsl,spi-rdy-drctl", &spi_drctl);
1807 if ((ret < 0) || (spi_drctl >= 0x3)) {
1808 /* '11' is reserved */
1809 spi_drctl = 0;
1810 }
1811
1812 platform_set_drvdata(pdev, controller);
1813
1814 controller->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1815 controller->bus_num = np ? -1 : pdev->id;
1816 controller->use_gpio_descriptors = true;
1817
1818 spi_imx = spi_controller_get_devdata(controller);
1819 spi_imx->controller = controller;
1820 spi_imx->dev = &pdev->dev;
1821 spi_imx->target_mode = target_mode;
1822
1823 spi_imx->devtype_data = devtype_data;
1824
1825 /*
1826 * Get number of chip selects from device properties. This can be
1827 * coming from device tree or boardfiles, if it is not defined,
1828 * a default value of 3 chip selects will be used, as all the legacy
1829 * board files have <= 3 chip selects.
1830 */
1831 if (!device_property_read_u32(&pdev->dev, "num-cs", &val))
1832 controller->num_chipselect = val;
1833 else
1834 controller->num_chipselect = 3;
1835
1836 controller->transfer_one = spi_imx_transfer_one;
1837 controller->setup = spi_imx_setup;
1838 controller->prepare_message = spi_imx_prepare_message;
1839 controller->unprepare_message = spi_imx_unprepare_message;
1840 controller->target_abort = spi_imx_target_abort;
1841 controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_NO_CS |
1842 SPI_MOSI_IDLE_LOW;
1843
1844 if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
1845 is_imx53_ecspi(spi_imx))
1846 controller->mode_bits |= SPI_LOOP | SPI_READY;
1847
1848 if (is_imx51_ecspi(spi_imx) || is_imx53_ecspi(spi_imx))
1849 controller->mode_bits |= SPI_RX_CPHA_FLIP;
1850
1851 if (is_imx51_ecspi(spi_imx) &&
1852 device_property_read_u32(&pdev->dev, "cs-gpios", NULL))
1853 /*
1854 * When using HW-CS implementing SPI_CS_WORD can be done by just
1855 * setting the burst length to the word size. This is
1856 * considerably faster than manually controlling the CS.
1857 */
1858 controller->mode_bits |= SPI_CS_WORD;
1859
1860 if (is_imx51_ecspi(spi_imx) || is_imx53_ecspi(spi_imx)) {
1861 controller->max_native_cs = 4;
1862 controller->flags |= SPI_CONTROLLER_GPIO_SS;
1863 }
1864
1865 spi_imx->spi_drctl = spi_drctl;
1866
1867 init_completion(&spi_imx->xfer_done);
1868
1869 spi_imx->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1870 if (IS_ERR(spi_imx->base)) {
1871 ret = PTR_ERR(spi_imx->base);
1872 goto out_controller_put;
1873 }
1874 spi_imx->base_phys = res->start;
1875
1876 irq = platform_get_irq(pdev, 0);
1877 if (irq < 0) {
1878 ret = irq;
1879 goto out_controller_put;
1880 }
1881
1882 ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1883 dev_name(&pdev->dev), spi_imx);
1884 if (ret) {
1885 dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1886 goto out_controller_put;
1887 }
1888
1889 spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1890 if (IS_ERR(spi_imx->clk_ipg)) {
1891 ret = PTR_ERR(spi_imx->clk_ipg);
1892 goto out_controller_put;
1893 }
1894
1895 spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1896 if (IS_ERR(spi_imx->clk_per)) {
1897 ret = PTR_ERR(spi_imx->clk_per);
1898 goto out_controller_put;
1899 }
1900
1901 ret = clk_prepare_enable(spi_imx->clk_per);
1902 if (ret)
1903 goto out_controller_put;
1904
1905 ret = clk_prepare_enable(spi_imx->clk_ipg);
1906 if (ret)
1907 goto out_put_per;
1908
1909 pm_runtime_set_autosuspend_delay(spi_imx->dev, MXC_RPM_TIMEOUT);
1910 pm_runtime_use_autosuspend(spi_imx->dev);
1911 pm_runtime_get_noresume(spi_imx->dev);
1912 pm_runtime_set_active(spi_imx->dev);
1913 pm_runtime_enable(spi_imx->dev);
1914
1915 spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1916 /*
1917 * Only validated on i.mx35 and i.mx6 now, can remove the constraint
1918 * if validated on other chips.
1919 */
1920 if (spi_imx->devtype_data->has_dmamode) {
1921 ret = spi_imx_sdma_init(&pdev->dev, spi_imx, controller);
1922 if (ret == -EPROBE_DEFER)
1923 goto out_runtime_pm_put;
1924
1925 if (ret < 0)
1926 dev_dbg(&pdev->dev, "dma setup error %d, use pio\n",
1927 ret);
1928 }
1929
1930 spi_imx->devtype_data->reset(spi_imx);
1931
1932 spi_imx->devtype_data->intctrl(spi_imx, 0);
1933
1934 controller->dev.of_node = pdev->dev.of_node;
1935 ret = spi_register_controller(controller);
1936 if (ret) {
1937 dev_err_probe(&pdev->dev, ret, "register controller failed\n");
1938 goto out_register_controller;
1939 }
1940
1941 pm_runtime_put_autosuspend(spi_imx->dev);
1942
1943 return ret;
1944
1945 out_register_controller:
1946 if (spi_imx->devtype_data->has_dmamode)
1947 spi_imx_sdma_exit(spi_imx);
1948 out_runtime_pm_put:
1949 pm_runtime_dont_use_autosuspend(spi_imx->dev);
1950 pm_runtime_disable(spi_imx->dev);
1951 pm_runtime_set_suspended(&pdev->dev);
1952
1953 clk_disable_unprepare(spi_imx->clk_ipg);
1954 out_put_per:
1955 clk_disable_unprepare(spi_imx->clk_per);
1956 out_controller_put:
1957 spi_controller_put(controller);
1958
1959 return ret;
1960 }
1961
spi_imx_remove(struct platform_device * pdev)1962 static void spi_imx_remove(struct platform_device *pdev)
1963 {
1964 struct spi_controller *controller = platform_get_drvdata(pdev);
1965 struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
1966 int ret;
1967
1968 spi_unregister_controller(controller);
1969
1970 ret = pm_runtime_get_sync(spi_imx->dev);
1971 if (ret >= 0)
1972 writel(0, spi_imx->base + MXC_CSPICTRL);
1973 else
1974 dev_warn(spi_imx->dev, "failed to enable clock, skip hw disable\n");
1975
1976 pm_runtime_dont_use_autosuspend(spi_imx->dev);
1977 pm_runtime_put_sync(spi_imx->dev);
1978 pm_runtime_disable(spi_imx->dev);
1979
1980 spi_imx_sdma_exit(spi_imx);
1981 }
1982
spi_imx_runtime_resume(struct device * dev)1983 static int spi_imx_runtime_resume(struct device *dev)
1984 {
1985 struct spi_controller *controller = dev_get_drvdata(dev);
1986 struct spi_imx_data *spi_imx;
1987 int ret;
1988
1989 spi_imx = spi_controller_get_devdata(controller);
1990
1991 ret = clk_prepare_enable(spi_imx->clk_per);
1992 if (ret)
1993 return ret;
1994
1995 ret = clk_prepare_enable(spi_imx->clk_ipg);
1996 if (ret) {
1997 clk_disable_unprepare(spi_imx->clk_per);
1998 return ret;
1999 }
2000
2001 return 0;
2002 }
2003
spi_imx_runtime_suspend(struct device * dev)2004 static int spi_imx_runtime_suspend(struct device *dev)
2005 {
2006 struct spi_controller *controller = dev_get_drvdata(dev);
2007 struct spi_imx_data *spi_imx;
2008
2009 spi_imx = spi_controller_get_devdata(controller);
2010
2011 clk_disable_unprepare(spi_imx->clk_per);
2012 clk_disable_unprepare(spi_imx->clk_ipg);
2013
2014 return 0;
2015 }
2016
spi_imx_suspend(struct device * dev)2017 static int spi_imx_suspend(struct device *dev)
2018 {
2019 pinctrl_pm_select_sleep_state(dev);
2020 return 0;
2021 }
2022
spi_imx_resume(struct device * dev)2023 static int spi_imx_resume(struct device *dev)
2024 {
2025 pinctrl_pm_select_default_state(dev);
2026 return 0;
2027 }
2028
2029 static const struct dev_pm_ops imx_spi_pm = {
2030 RUNTIME_PM_OPS(spi_imx_runtime_suspend, spi_imx_runtime_resume, NULL)
2031 SYSTEM_SLEEP_PM_OPS(spi_imx_suspend, spi_imx_resume)
2032 };
2033
2034 static struct platform_driver spi_imx_driver = {
2035 .driver = {
2036 .name = DRIVER_NAME,
2037 .of_match_table = spi_imx_dt_ids,
2038 .pm = pm_ptr(&imx_spi_pm),
2039 },
2040 .probe = spi_imx_probe,
2041 .remove = spi_imx_remove,
2042 };
2043 module_platform_driver(spi_imx_driver);
2044
2045 MODULE_DESCRIPTION("i.MX SPI Controller driver");
2046 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
2047 MODULE_LICENSE("GPL");
2048 MODULE_ALIAS("platform:" DRIVER_NAME);
2049