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Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux...
[deliverable/linux.git] / drivers / spi / spi-pxa2xx.c
1 /*
2 * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
3 * Copyright (C) 2013, Intel Corporation
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 */
15
16 #include <linux/bitops.h>
17 #include <linux/init.h>
18 #include <linux/module.h>
19 #include <linux/device.h>
20 #include <linux/ioport.h>
21 #include <linux/errno.h>
22 #include <linux/err.h>
23 #include <linux/interrupt.h>
24 #include <linux/kernel.h>
25 #include <linux/pci.h>
26 #include <linux/platform_device.h>
27 #include <linux/spi/pxa2xx_spi.h>
28 #include <linux/spi/spi.h>
29 #include <linux/delay.h>
30 #include <linux/gpio.h>
31 #include <linux/slab.h>
32 #include <linux/clk.h>
33 #include <linux/pm_runtime.h>
34 #include <linux/acpi.h>
35
36 #include "spi-pxa2xx.h"
37
38 MODULE_AUTHOR("Stephen Street");
39 MODULE_DESCRIPTION("PXA2xx SSP SPI Controller");
40 MODULE_LICENSE("GPL");
41 MODULE_ALIAS("platform:pxa2xx-spi");
42
43 #define TIMOUT_DFLT 1000
44
45 /*
46 * for testing SSCR1 changes that require SSP restart, basically
47 * everything except the service and interrupt enables, the pxa270 developer
48 * manual says only SSCR1_SCFR, SSCR1_SPH, SSCR1_SPO need to be in this
49 * list, but the PXA255 dev man says all bits without really meaning the
50 * service and interrupt enables
51 */
52 #define SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_SCFR \
53 | SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \
54 | SSCR1_SFRMDIR | SSCR1_RWOT | SSCR1_TRAIL \
55 | SSCR1_IFS | SSCR1_STRF | SSCR1_EFWR \
56 | SSCR1_RFT | SSCR1_TFT | SSCR1_MWDS \
57 | SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
58
59 #define QUARK_X1000_SSCR1_CHANGE_MASK (QUARK_X1000_SSCR1_STRF \
60 | QUARK_X1000_SSCR1_EFWR \
61 | QUARK_X1000_SSCR1_RFT \
62 | QUARK_X1000_SSCR1_TFT \
63 | SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
64
65 #define LPSS_GENERAL_REG_RXTO_HOLDOFF_DISABLE BIT(24)
66 #define LPSS_CS_CONTROL_SW_MODE BIT(0)
67 #define LPSS_CS_CONTROL_CS_HIGH BIT(1)
68 #define LPSS_CAPS_CS_EN_SHIFT 9
69 #define LPSS_CAPS_CS_EN_MASK (0xf << LPSS_CAPS_CS_EN_SHIFT)
70
71 struct lpss_config {
72 /* LPSS offset from drv_data->ioaddr */
73 unsigned offset;
74 /* Register offsets from drv_data->lpss_base or -1 */
75 int reg_general;
76 int reg_ssp;
77 int reg_cs_ctrl;
78 int reg_capabilities;
79 /* FIFO thresholds */
80 u32 rx_threshold;
81 u32 tx_threshold_lo;
82 u32 tx_threshold_hi;
83 /* Chip select control */
84 unsigned cs_sel_shift;
85 unsigned cs_sel_mask;
86 unsigned cs_num;
87 };
88
89 /* Keep these sorted with enum pxa_ssp_type */
90 static const struct lpss_config lpss_platforms[] = {
91 { /* LPSS_LPT_SSP */
92 .offset = 0x800,
93 .reg_general = 0x08,
94 .reg_ssp = 0x0c,
95 .reg_cs_ctrl = 0x18,
96 .reg_capabilities = -1,
97 .rx_threshold = 64,
98 .tx_threshold_lo = 160,
99 .tx_threshold_hi = 224,
100 },
101 { /* LPSS_BYT_SSP */
102 .offset = 0x400,
103 .reg_general = 0x08,
104 .reg_ssp = 0x0c,
105 .reg_cs_ctrl = 0x18,
106 .reg_capabilities = -1,
107 .rx_threshold = 64,
108 .tx_threshold_lo = 160,
109 .tx_threshold_hi = 224,
110 },
111 { /* LPSS_BSW_SSP */
112 .offset = 0x400,
113 .reg_general = 0x08,
114 .reg_ssp = 0x0c,
115 .reg_cs_ctrl = 0x18,
116 .reg_capabilities = -1,
117 .rx_threshold = 64,
118 .tx_threshold_lo = 160,
119 .tx_threshold_hi = 224,
120 .cs_sel_shift = 2,
121 .cs_sel_mask = 1 << 2,
122 .cs_num = 2,
123 },
124 { /* LPSS_SPT_SSP */
125 .offset = 0x200,
126 .reg_general = -1,
127 .reg_ssp = 0x20,
128 .reg_cs_ctrl = 0x24,
129 .reg_capabilities = -1,
130 .rx_threshold = 1,
131 .tx_threshold_lo = 32,
132 .tx_threshold_hi = 56,
133 },
134 { /* LPSS_BXT_SSP */
135 .offset = 0x200,
136 .reg_general = -1,
137 .reg_ssp = 0x20,
138 .reg_cs_ctrl = 0x24,
139 .reg_capabilities = 0xfc,
140 .rx_threshold = 1,
141 .tx_threshold_lo = 16,
142 .tx_threshold_hi = 48,
143 .cs_sel_shift = 8,
144 .cs_sel_mask = 3 << 8,
145 },
146 };
147
148 static inline const struct lpss_config
149 *lpss_get_config(const struct driver_data *drv_data)
150 {
151 return &lpss_platforms[drv_data->ssp_type - LPSS_LPT_SSP];
152 }
153
154 static bool is_lpss_ssp(const struct driver_data *drv_data)
155 {
156 switch (drv_data->ssp_type) {
157 case LPSS_LPT_SSP:
158 case LPSS_BYT_SSP:
159 case LPSS_BSW_SSP:
160 case LPSS_SPT_SSP:
161 case LPSS_BXT_SSP:
162 return true;
163 default:
164 return false;
165 }
166 }
167
168 static bool is_quark_x1000_ssp(const struct driver_data *drv_data)
169 {
170 return drv_data->ssp_type == QUARK_X1000_SSP;
171 }
172
173 static u32 pxa2xx_spi_get_ssrc1_change_mask(const struct driver_data *drv_data)
174 {
175 switch (drv_data->ssp_type) {
176 case QUARK_X1000_SSP:
177 return QUARK_X1000_SSCR1_CHANGE_MASK;
178 default:
179 return SSCR1_CHANGE_MASK;
180 }
181 }
182
183 static u32
184 pxa2xx_spi_get_rx_default_thre(const struct driver_data *drv_data)
185 {
186 switch (drv_data->ssp_type) {
187 case QUARK_X1000_SSP:
188 return RX_THRESH_QUARK_X1000_DFLT;
189 default:
190 return RX_THRESH_DFLT;
191 }
192 }
193
194 static bool pxa2xx_spi_txfifo_full(const struct driver_data *drv_data)
195 {
196 u32 mask;
197
198 switch (drv_data->ssp_type) {
199 case QUARK_X1000_SSP:
200 mask = QUARK_X1000_SSSR_TFL_MASK;
201 break;
202 default:
203 mask = SSSR_TFL_MASK;
204 break;
205 }
206
207 return (pxa2xx_spi_read(drv_data, SSSR) & mask) == mask;
208 }
209
210 static void pxa2xx_spi_clear_rx_thre(const struct driver_data *drv_data,
211 u32 *sccr1_reg)
212 {
213 u32 mask;
214
215 switch (drv_data->ssp_type) {
216 case QUARK_X1000_SSP:
217 mask = QUARK_X1000_SSCR1_RFT;
218 break;
219 default:
220 mask = SSCR1_RFT;
221 break;
222 }
223 *sccr1_reg &= ~mask;
224 }
225
226 static void pxa2xx_spi_set_rx_thre(const struct driver_data *drv_data,
227 u32 *sccr1_reg, u32 threshold)
228 {
229 switch (drv_data->ssp_type) {
230 case QUARK_X1000_SSP:
231 *sccr1_reg |= QUARK_X1000_SSCR1_RxTresh(threshold);
232 break;
233 default:
234 *sccr1_reg |= SSCR1_RxTresh(threshold);
235 break;
236 }
237 }
238
239 static u32 pxa2xx_configure_sscr0(const struct driver_data *drv_data,
240 u32 clk_div, u8 bits)
241 {
242 switch (drv_data->ssp_type) {
243 case QUARK_X1000_SSP:
244 return clk_div
245 | QUARK_X1000_SSCR0_Motorola
246 | QUARK_X1000_SSCR0_DataSize(bits > 32 ? 8 : bits)
247 | SSCR0_SSE;
248 default:
249 return clk_div
250 | SSCR0_Motorola
251 | SSCR0_DataSize(bits > 16 ? bits - 16 : bits)
252 | SSCR0_SSE
253 | (bits > 16 ? SSCR0_EDSS : 0);
254 }
255 }
256
257 /*
258 * Read and write LPSS SSP private registers. Caller must first check that
259 * is_lpss_ssp() returns true before these can be called.
260 */
261 static u32 __lpss_ssp_read_priv(struct driver_data *drv_data, unsigned offset)
262 {
263 WARN_ON(!drv_data->lpss_base);
264 return readl(drv_data->lpss_base + offset);
265 }
266
267 static void __lpss_ssp_write_priv(struct driver_data *drv_data,
268 unsigned offset, u32 value)
269 {
270 WARN_ON(!drv_data->lpss_base);
271 writel(value, drv_data->lpss_base + offset);
272 }
273
274 /*
275 * lpss_ssp_setup - perform LPSS SSP specific setup
276 * @drv_data: pointer to the driver private data
277 *
278 * Perform LPSS SSP specific setup. This function must be called first if
279 * one is going to use LPSS SSP private registers.
280 */
281 static void lpss_ssp_setup(struct driver_data *drv_data)
282 {
283 const struct lpss_config *config;
284 u32 value;
285
286 config = lpss_get_config(drv_data);
287 drv_data->lpss_base = drv_data->ioaddr + config->offset;
288
289 /* Enable software chip select control */
290 value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
291 value &= ~(LPSS_CS_CONTROL_SW_MODE | LPSS_CS_CONTROL_CS_HIGH);
292 value |= LPSS_CS_CONTROL_SW_MODE | LPSS_CS_CONTROL_CS_HIGH;
293 __lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
294
295 /* Enable multiblock DMA transfers */
296 if (drv_data->master_info->enable_dma) {
297 __lpss_ssp_write_priv(drv_data, config->reg_ssp, 1);
298
299 if (config->reg_general >= 0) {
300 value = __lpss_ssp_read_priv(drv_data,
301 config->reg_general);
302 value |= LPSS_GENERAL_REG_RXTO_HOLDOFF_DISABLE;
303 __lpss_ssp_write_priv(drv_data,
304 config->reg_general, value);
305 }
306 }
307 }
308
309 static void lpss_ssp_select_cs(struct driver_data *drv_data,
310 const struct lpss_config *config)
311 {
312 u32 value, cs;
313
314 if (!config->cs_sel_mask)
315 return;
316
317 value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
318
319 cs = drv_data->cur_msg->spi->chip_select;
320 cs <<= config->cs_sel_shift;
321 if (cs != (value & config->cs_sel_mask)) {
322 /*
323 * When switching another chip select output active the
324 * output must be selected first and wait 2 ssp_clk cycles
325 * before changing state to active. Otherwise a short
326 * glitch will occur on the previous chip select since
327 * output select is latched but state control is not.
328 */
329 value &= ~config->cs_sel_mask;
330 value |= cs;
331 __lpss_ssp_write_priv(drv_data,
332 config->reg_cs_ctrl, value);
333 ndelay(1000000000 /
334 (drv_data->master->max_speed_hz / 2));
335 }
336 }
337
338 static void lpss_ssp_cs_control(struct driver_data *drv_data, bool enable)
339 {
340 const struct lpss_config *config;
341 u32 value;
342
343 config = lpss_get_config(drv_data);
344
345 if (enable)
346 lpss_ssp_select_cs(drv_data, config);
347
348 value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
349 if (enable)
350 value &= ~LPSS_CS_CONTROL_CS_HIGH;
351 else
352 value |= LPSS_CS_CONTROL_CS_HIGH;
353 __lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
354 }
355
356 static void cs_assert(struct driver_data *drv_data)
357 {
358 struct chip_data *chip = drv_data->cur_chip;
359
360 if (drv_data->ssp_type == CE4100_SSP) {
361 pxa2xx_spi_write(drv_data, SSSR, drv_data->cur_chip->frm);
362 return;
363 }
364
365 if (chip->cs_control) {
366 chip->cs_control(PXA2XX_CS_ASSERT);
367 return;
368 }
369
370 if (gpio_is_valid(chip->gpio_cs)) {
371 gpio_set_value(chip->gpio_cs, chip->gpio_cs_inverted);
372 return;
373 }
374
375 if (is_lpss_ssp(drv_data))
376 lpss_ssp_cs_control(drv_data, true);
377 }
378
379 static void cs_deassert(struct driver_data *drv_data)
380 {
381 struct chip_data *chip = drv_data->cur_chip;
382
383 if (drv_data->ssp_type == CE4100_SSP)
384 return;
385
386 if (chip->cs_control) {
387 chip->cs_control(PXA2XX_CS_DEASSERT);
388 return;
389 }
390
391 if (gpio_is_valid(chip->gpio_cs)) {
392 gpio_set_value(chip->gpio_cs, !chip->gpio_cs_inverted);
393 return;
394 }
395
396 if (is_lpss_ssp(drv_data))
397 lpss_ssp_cs_control(drv_data, false);
398 }
399
400 int pxa2xx_spi_flush(struct driver_data *drv_data)
401 {
402 unsigned long limit = loops_per_jiffy << 1;
403
404 do {
405 while (pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
406 pxa2xx_spi_read(drv_data, SSDR);
407 } while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY) && --limit);
408 write_SSSR_CS(drv_data, SSSR_ROR);
409
410 return limit;
411 }
412
413 static int null_writer(struct driver_data *drv_data)
414 {
415 u8 n_bytes = drv_data->n_bytes;
416
417 if (pxa2xx_spi_txfifo_full(drv_data)
418 || (drv_data->tx == drv_data->tx_end))
419 return 0;
420
421 pxa2xx_spi_write(drv_data, SSDR, 0);
422 drv_data->tx += n_bytes;
423
424 return 1;
425 }
426
427 static int null_reader(struct driver_data *drv_data)
428 {
429 u8 n_bytes = drv_data->n_bytes;
430
431 while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
432 && (drv_data->rx < drv_data->rx_end)) {
433 pxa2xx_spi_read(drv_data, SSDR);
434 drv_data->rx += n_bytes;
435 }
436
437 return drv_data->rx == drv_data->rx_end;
438 }
439
440 static int u8_writer(struct driver_data *drv_data)
441 {
442 if (pxa2xx_spi_txfifo_full(drv_data)
443 || (drv_data->tx == drv_data->tx_end))
444 return 0;
445
446 pxa2xx_spi_write(drv_data, SSDR, *(u8 *)(drv_data->tx));
447 ++drv_data->tx;
448
449 return 1;
450 }
451
452 static int u8_reader(struct driver_data *drv_data)
453 {
454 while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
455 && (drv_data->rx < drv_data->rx_end)) {
456 *(u8 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
457 ++drv_data->rx;
458 }
459
460 return drv_data->rx == drv_data->rx_end;
461 }
462
463 static int u16_writer(struct driver_data *drv_data)
464 {
465 if (pxa2xx_spi_txfifo_full(drv_data)
466 || (drv_data->tx == drv_data->tx_end))
467 return 0;
468
469 pxa2xx_spi_write(drv_data, SSDR, *(u16 *)(drv_data->tx));
470 drv_data->tx += 2;
471
472 return 1;
473 }
474
475 static int u16_reader(struct driver_data *drv_data)
476 {
477 while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
478 && (drv_data->rx < drv_data->rx_end)) {
479 *(u16 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
480 drv_data->rx += 2;
481 }
482
483 return drv_data->rx == drv_data->rx_end;
484 }
485
486 static int u32_writer(struct driver_data *drv_data)
487 {
488 if (pxa2xx_spi_txfifo_full(drv_data)
489 || (drv_data->tx == drv_data->tx_end))
490 return 0;
491
492 pxa2xx_spi_write(drv_data, SSDR, *(u32 *)(drv_data->tx));
493 drv_data->tx += 4;
494
495 return 1;
496 }
497
498 static int u32_reader(struct driver_data *drv_data)
499 {
500 while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
501 && (drv_data->rx < drv_data->rx_end)) {
502 *(u32 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
503 drv_data->rx += 4;
504 }
505
506 return drv_data->rx == drv_data->rx_end;
507 }
508
509 void *pxa2xx_spi_next_transfer(struct driver_data *drv_data)
510 {
511 struct spi_message *msg = drv_data->cur_msg;
512 struct spi_transfer *trans = drv_data->cur_transfer;
513
514 /* Move to next transfer */
515 if (trans->transfer_list.next != &msg->transfers) {
516 drv_data->cur_transfer =
517 list_entry(trans->transfer_list.next,
518 struct spi_transfer,
519 transfer_list);
520 return RUNNING_STATE;
521 } else
522 return DONE_STATE;
523 }
524
525 /* caller already set message->status; dma and pio irqs are blocked */
526 static void giveback(struct driver_data *drv_data)
527 {
528 struct spi_transfer* last_transfer;
529 struct spi_message *msg;
530 unsigned long timeout;
531
532 msg = drv_data->cur_msg;
533 drv_data->cur_msg = NULL;
534 drv_data->cur_transfer = NULL;
535
536 last_transfer = list_last_entry(&msg->transfers, struct spi_transfer,
537 transfer_list);
538
539 /* Delay if requested before any change in chip select */
540 if (last_transfer->delay_usecs)
541 udelay(last_transfer->delay_usecs);
542
543 /* Wait until SSP becomes idle before deasserting the CS */
544 timeout = jiffies + msecs_to_jiffies(10);
545 while (pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY &&
546 !time_after(jiffies, timeout))
547 cpu_relax();
548
549 /* Drop chip select UNLESS cs_change is true or we are returning
550 * a message with an error, or next message is for another chip
551 */
552 if (!last_transfer->cs_change)
553 cs_deassert(drv_data);
554 else {
555 struct spi_message *next_msg;
556
557 /* Holding of cs was hinted, but we need to make sure
558 * the next message is for the same chip. Don't waste
559 * time with the following tests unless this was hinted.
560 *
561 * We cannot postpone this until pump_messages, because
562 * after calling msg->complete (below) the driver that
563 * sent the current message could be unloaded, which
564 * could invalidate the cs_control() callback...
565 */
566
567 /* get a pointer to the next message, if any */
568 next_msg = spi_get_next_queued_message(drv_data->master);
569
570 /* see if the next and current messages point
571 * to the same chip
572 */
573 if ((next_msg && next_msg->spi != msg->spi) ||
574 msg->state == ERROR_STATE)
575 cs_deassert(drv_data);
576 }
577
578 drv_data->cur_chip = NULL;
579 spi_finalize_current_message(drv_data->master);
580 }
581
582 static void reset_sccr1(struct driver_data *drv_data)
583 {
584 struct chip_data *chip = drv_data->cur_chip;
585 u32 sccr1_reg;
586
587 sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1) & ~drv_data->int_cr1;
588 switch (drv_data->ssp_type) {
589 case QUARK_X1000_SSP:
590 sccr1_reg &= ~QUARK_X1000_SSCR1_RFT;
591 break;
592 default:
593 sccr1_reg &= ~SSCR1_RFT;
594 break;
595 }
596 sccr1_reg |= chip->threshold;
597 pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
598 }
599
600 static void int_error_stop(struct driver_data *drv_data, const char* msg)
601 {
602 /* Stop and reset SSP */
603 write_SSSR_CS(drv_data, drv_data->clear_sr);
604 reset_sccr1(drv_data);
605 if (!pxa25x_ssp_comp(drv_data))
606 pxa2xx_spi_write(drv_data, SSTO, 0);
607 pxa2xx_spi_flush(drv_data);
608 pxa2xx_spi_write(drv_data, SSCR0,
609 pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
610
611 dev_err(&drv_data->pdev->dev, "%s\n", msg);
612
613 drv_data->cur_msg->state = ERROR_STATE;
614 tasklet_schedule(&drv_data->pump_transfers);
615 }
616
617 static void int_transfer_complete(struct driver_data *drv_data)
618 {
619 /* Clear and disable interrupts */
620 write_SSSR_CS(drv_data, drv_data->clear_sr);
621 reset_sccr1(drv_data);
622 if (!pxa25x_ssp_comp(drv_data))
623 pxa2xx_spi_write(drv_data, SSTO, 0);
624
625 /* Update total byte transferred return count actual bytes read */
626 drv_data->cur_msg->actual_length += drv_data->len -
627 (drv_data->rx_end - drv_data->rx);
628
629 /* Transfer delays and chip select release are
630 * handled in pump_transfers or giveback
631 */
632
633 /* Move to next transfer */
634 drv_data->cur_msg->state = pxa2xx_spi_next_transfer(drv_data);
635
636 /* Schedule transfer tasklet */
637 tasklet_schedule(&drv_data->pump_transfers);
638 }
639
640 static irqreturn_t interrupt_transfer(struct driver_data *drv_data)
641 {
642 u32 irq_mask = (pxa2xx_spi_read(drv_data, SSCR1) & SSCR1_TIE) ?
643 drv_data->mask_sr : drv_data->mask_sr & ~SSSR_TFS;
644
645 u32 irq_status = pxa2xx_spi_read(drv_data, SSSR) & irq_mask;
646
647 if (irq_status & SSSR_ROR) {
648 int_error_stop(drv_data, "interrupt_transfer: fifo overrun");
649 return IRQ_HANDLED;
650 }
651
652 if (irq_status & SSSR_TINT) {
653 pxa2xx_spi_write(drv_data, SSSR, SSSR_TINT);
654 if (drv_data->read(drv_data)) {
655 int_transfer_complete(drv_data);
656 return IRQ_HANDLED;
657 }
658 }
659
660 /* Drain rx fifo, Fill tx fifo and prevent overruns */
661 do {
662 if (drv_data->read(drv_data)) {
663 int_transfer_complete(drv_data);
664 return IRQ_HANDLED;
665 }
666 } while (drv_data->write(drv_data));
667
668 if (drv_data->read(drv_data)) {
669 int_transfer_complete(drv_data);
670 return IRQ_HANDLED;
671 }
672
673 if (drv_data->tx == drv_data->tx_end) {
674 u32 bytes_left;
675 u32 sccr1_reg;
676
677 sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1);
678 sccr1_reg &= ~SSCR1_TIE;
679
680 /*
681 * PXA25x_SSP has no timeout, set up rx threshould for the
682 * remaining RX bytes.
683 */
684 if (pxa25x_ssp_comp(drv_data)) {
685 u32 rx_thre;
686
687 pxa2xx_spi_clear_rx_thre(drv_data, &sccr1_reg);
688
689 bytes_left = drv_data->rx_end - drv_data->rx;
690 switch (drv_data->n_bytes) {
691 case 4:
692 bytes_left >>= 1;
693 case 2:
694 bytes_left >>= 1;
695 }
696
697 rx_thre = pxa2xx_spi_get_rx_default_thre(drv_data);
698 if (rx_thre > bytes_left)
699 rx_thre = bytes_left;
700
701 pxa2xx_spi_set_rx_thre(drv_data, &sccr1_reg, rx_thre);
702 }
703 pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
704 }
705
706 /* We did something */
707 return IRQ_HANDLED;
708 }
709
710 static irqreturn_t ssp_int(int irq, void *dev_id)
711 {
712 struct driver_data *drv_data = dev_id;
713 u32 sccr1_reg;
714 u32 mask = drv_data->mask_sr;
715 u32 status;
716
717 /*
718 * The IRQ might be shared with other peripherals so we must first
719 * check that are we RPM suspended or not. If we are we assume that
720 * the IRQ was not for us (we shouldn't be RPM suspended when the
721 * interrupt is enabled).
722 */
723 if (pm_runtime_suspended(&drv_data->pdev->dev))
724 return IRQ_NONE;
725
726 /*
727 * If the device is not yet in RPM suspended state and we get an
728 * interrupt that is meant for another device, check if status bits
729 * are all set to one. That means that the device is already
730 * powered off.
731 */
732 status = pxa2xx_spi_read(drv_data, SSSR);
733 if (status == ~0)
734 return IRQ_NONE;
735
736 sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1);
737
738 /* Ignore possible writes if we don't need to write */
739 if (!(sccr1_reg & SSCR1_TIE))
740 mask &= ~SSSR_TFS;
741
742 /* Ignore RX timeout interrupt if it is disabled */
743 if (!(sccr1_reg & SSCR1_TINTE))
744 mask &= ~SSSR_TINT;
745
746 if (!(status & mask))
747 return IRQ_NONE;
748
749 if (!drv_data->cur_msg) {
750
751 pxa2xx_spi_write(drv_data, SSCR0,
752 pxa2xx_spi_read(drv_data, SSCR0)
753 & ~SSCR0_SSE);
754 pxa2xx_spi_write(drv_data, SSCR1,
755 pxa2xx_spi_read(drv_data, SSCR1)
756 & ~drv_data->int_cr1);
757 if (!pxa25x_ssp_comp(drv_data))
758 pxa2xx_spi_write(drv_data, SSTO, 0);
759 write_SSSR_CS(drv_data, drv_data->clear_sr);
760
761 dev_err(&drv_data->pdev->dev,
762 "bad message state in interrupt handler\n");
763
764 /* Never fail */
765 return IRQ_HANDLED;
766 }
767
768 return drv_data->transfer_handler(drv_data);
769 }
770
771 /*
772 * The Quark SPI has an additional 24 bit register (DDS_CLK_RATE) to multiply
773 * input frequency by fractions of 2^24. It also has a divider by 5.
774 *
775 * There are formulas to get baud rate value for given input frequency and
776 * divider parameters, such as DDS_CLK_RATE and SCR:
777 *
778 * Fsys = 200MHz
779 *
780 * Fssp = Fsys * DDS_CLK_RATE / 2^24 (1)
781 * Baud rate = Fsclk = Fssp / (2 * (SCR + 1)) (2)
782 *
783 * DDS_CLK_RATE either 2^n or 2^n / 5.
784 * SCR is in range 0 .. 255
785 *
786 * Divisor = 5^i * 2^j * 2 * k
787 * i = [0, 1] i = 1 iff j = 0 or j > 3
788 * j = [0, 23] j = 0 iff i = 1
789 * k = [1, 256]
790 * Special case: j = 0, i = 1: Divisor = 2 / 5
791 *
792 * Accordingly to the specification the recommended values for DDS_CLK_RATE
793 * are:
794 * Case 1: 2^n, n = [0, 23]
795 * Case 2: 2^24 * 2 / 5 (0x666666)
796 * Case 3: less than or equal to 2^24 / 5 / 16 (0x33333)
797 *
798 * In all cases the lowest possible value is better.
799 *
800 * The function calculates parameters for all cases and chooses the one closest
801 * to the asked baud rate.
802 */
803 static unsigned int quark_x1000_get_clk_div(int rate, u32 *dds)
804 {
805 unsigned long xtal = 200000000;
806 unsigned long fref = xtal / 2; /* mandatory division by 2,
807 see (2) */
808 /* case 3 */
809 unsigned long fref1 = fref / 2; /* case 1 */
810 unsigned long fref2 = fref * 2 / 5; /* case 2 */
811 unsigned long scale;
812 unsigned long q, q1, q2;
813 long r, r1, r2;
814 u32 mul;
815
816 /* Case 1 */
817
818 /* Set initial value for DDS_CLK_RATE */
819 mul = (1 << 24) >> 1;
820
821 /* Calculate initial quot */
822 q1 = DIV_ROUND_UP(fref1, rate);
823
824 /* Scale q1 if it's too big */
825 if (q1 > 256) {
826 /* Scale q1 to range [1, 512] */
827 scale = fls_long(q1 - 1);
828 if (scale > 9) {
829 q1 >>= scale - 9;
830 mul >>= scale - 9;
831 }
832
833 /* Round the result if we have a remainder */
834 q1 += q1 & 1;
835 }
836
837 /* Decrease DDS_CLK_RATE as much as we can without loss in precision */
838 scale = __ffs(q1);
839 q1 >>= scale;
840 mul >>= scale;
841
842 /* Get the remainder */
843 r1 = abs(fref1 / (1 << (24 - fls_long(mul))) / q1 - rate);
844
845 /* Case 2 */
846
847 q2 = DIV_ROUND_UP(fref2, rate);
848 r2 = abs(fref2 / q2 - rate);
849
850 /*
851 * Choose the best between two: less remainder we have the better. We
852 * can't go case 2 if q2 is greater than 256 since SCR register can
853 * hold only values 0 .. 255.
854 */
855 if (r2 >= r1 || q2 > 256) {
856 /* case 1 is better */
857 r = r1;
858 q = q1;
859 } else {
860 /* case 2 is better */
861 r = r2;
862 q = q2;
863 mul = (1 << 24) * 2 / 5;
864 }
865
866 /* Check case 3 only if the divisor is big enough */
867 if (fref / rate >= 80) {
868 u64 fssp;
869 u32 m;
870
871 /* Calculate initial quot */
872 q1 = DIV_ROUND_UP(fref, rate);
873 m = (1 << 24) / q1;
874
875 /* Get the remainder */
876 fssp = (u64)fref * m;
877 do_div(fssp, 1 << 24);
878 r1 = abs(fssp - rate);
879
880 /* Choose this one if it suits better */
881 if (r1 < r) {
882 /* case 3 is better */
883 q = 1;
884 mul = m;
885 }
886 }
887
888 *dds = mul;
889 return q - 1;
890 }
891
892 static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate)
893 {
894 unsigned long ssp_clk = drv_data->master->max_speed_hz;
895 const struct ssp_device *ssp = drv_data->ssp;
896
897 rate = min_t(int, ssp_clk, rate);
898
899 if (ssp->type == PXA25x_SSP || ssp->type == CE4100_SSP)
900 return (ssp_clk / (2 * rate) - 1) & 0xff;
901 else
902 return (ssp_clk / rate - 1) & 0xfff;
903 }
904
905 static unsigned int pxa2xx_ssp_get_clk_div(struct driver_data *drv_data,
906 int rate)
907 {
908 struct chip_data *chip = drv_data->cur_chip;
909 unsigned int clk_div;
910
911 switch (drv_data->ssp_type) {
912 case QUARK_X1000_SSP:
913 clk_div = quark_x1000_get_clk_div(rate, &chip->dds_rate);
914 break;
915 default:
916 clk_div = ssp_get_clk_div(drv_data, rate);
917 break;
918 }
919 return clk_div << 8;
920 }
921
922 static bool pxa2xx_spi_can_dma(struct spi_master *master,
923 struct spi_device *spi,
924 struct spi_transfer *xfer)
925 {
926 struct chip_data *chip = spi_get_ctldata(spi);
927
928 return chip->enable_dma &&
929 xfer->len <= MAX_DMA_LEN &&
930 xfer->len >= chip->dma_burst_size;
931 }
932
933 static void pump_transfers(unsigned long data)
934 {
935 struct driver_data *drv_data = (struct driver_data *)data;
936 struct spi_master *master = drv_data->master;
937 struct spi_message *message = NULL;
938 struct spi_transfer *transfer = NULL;
939 struct spi_transfer *previous = NULL;
940 struct chip_data *chip = NULL;
941 u32 clk_div = 0;
942 u8 bits = 0;
943 u32 speed = 0;
944 u32 cr0;
945 u32 cr1;
946 u32 dma_thresh = drv_data->cur_chip->dma_threshold;
947 u32 dma_burst = drv_data->cur_chip->dma_burst_size;
948 u32 change_mask = pxa2xx_spi_get_ssrc1_change_mask(drv_data);
949 int err;
950 int dma_mapped;
951
952 /* Get current state information */
953 message = drv_data->cur_msg;
954 transfer = drv_data->cur_transfer;
955 chip = drv_data->cur_chip;
956
957 /* Handle for abort */
958 if (message->state == ERROR_STATE) {
959 message->status = -EIO;
960 giveback(drv_data);
961 return;
962 }
963
964 /* Handle end of message */
965 if (message->state == DONE_STATE) {
966 message->status = 0;
967 giveback(drv_data);
968 return;
969 }
970
971 /* Delay if requested at end of transfer before CS change */
972 if (message->state == RUNNING_STATE) {
973 previous = list_entry(transfer->transfer_list.prev,
974 struct spi_transfer,
975 transfer_list);
976 if (previous->delay_usecs)
977 udelay(previous->delay_usecs);
978
979 /* Drop chip select only if cs_change is requested */
980 if (previous->cs_change)
981 cs_deassert(drv_data);
982 }
983
984 /* Check if we can DMA this transfer */
985 if (transfer->len > MAX_DMA_LEN && chip->enable_dma) {
986
987 /* reject already-mapped transfers; PIO won't always work */
988 if (message->is_dma_mapped
989 || transfer->rx_dma || transfer->tx_dma) {
990 dev_err(&drv_data->pdev->dev,
991 "pump_transfers: mapped transfer length of "
992 "%u is greater than %d\n",
993 transfer->len, MAX_DMA_LEN);
994 message->status = -EINVAL;
995 giveback(drv_data);
996 return;
997 }
998
999 /* warn ... we force this to PIO mode */
1000 dev_warn_ratelimited(&message->spi->dev,
1001 "pump_transfers: DMA disabled for transfer length %ld "
1002 "greater than %d\n",
1003 (long)drv_data->len, MAX_DMA_LEN);
1004 }
1005
1006 /* Setup the transfer state based on the type of transfer */
1007 if (pxa2xx_spi_flush(drv_data) == 0) {
1008 dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
1009 message->status = -EIO;
1010 giveback(drv_data);
1011 return;
1012 }
1013 drv_data->n_bytes = chip->n_bytes;
1014 drv_data->tx = (void *)transfer->tx_buf;
1015 drv_data->tx_end = drv_data->tx + transfer->len;
1016 drv_data->rx = transfer->rx_buf;
1017 drv_data->rx_end = drv_data->rx + transfer->len;
1018 drv_data->len = transfer->len;
1019 drv_data->write = drv_data->tx ? chip->write : null_writer;
1020 drv_data->read = drv_data->rx ? chip->read : null_reader;
1021
1022 /* Change speed and bit per word on a per transfer */
1023 bits = transfer->bits_per_word;
1024 speed = transfer->speed_hz;
1025
1026 clk_div = pxa2xx_ssp_get_clk_div(drv_data, speed);
1027
1028 if (bits <= 8) {
1029 drv_data->n_bytes = 1;
1030 drv_data->read = drv_data->read != null_reader ?
1031 u8_reader : null_reader;
1032 drv_data->write = drv_data->write != null_writer ?
1033 u8_writer : null_writer;
1034 } else if (bits <= 16) {
1035 drv_data->n_bytes = 2;
1036 drv_data->read = drv_data->read != null_reader ?
1037 u16_reader : null_reader;
1038 drv_data->write = drv_data->write != null_writer ?
1039 u16_writer : null_writer;
1040 } else if (bits <= 32) {
1041 drv_data->n_bytes = 4;
1042 drv_data->read = drv_data->read != null_reader ?
1043 u32_reader : null_reader;
1044 drv_data->write = drv_data->write != null_writer ?
1045 u32_writer : null_writer;
1046 }
1047 /*
1048 * if bits/word is changed in dma mode, then must check the
1049 * thresholds and burst also
1050 */
1051 if (chip->enable_dma) {
1052 if (pxa2xx_spi_set_dma_burst_and_threshold(chip,
1053 message->spi,
1054 bits, &dma_burst,
1055 &dma_thresh))
1056 dev_warn_ratelimited(&message->spi->dev,
1057 "pump_transfers: DMA burst size reduced to match bits_per_word\n");
1058 }
1059
1060 message->state = RUNNING_STATE;
1061
1062 dma_mapped = master->can_dma &&
1063 master->can_dma(master, message->spi, transfer) &&
1064 master->cur_msg_mapped;
1065 if (dma_mapped) {
1066
1067 /* Ensure we have the correct interrupt handler */
1068 drv_data->transfer_handler = pxa2xx_spi_dma_transfer;
1069
1070 err = pxa2xx_spi_dma_prepare(drv_data, dma_burst);
1071 if (err) {
1072 message->status = err;
1073 giveback(drv_data);
1074 return;
1075 }
1076
1077 /* Clear status and start DMA engine */
1078 cr1 = chip->cr1 | dma_thresh | drv_data->dma_cr1;
1079 pxa2xx_spi_write(drv_data, SSSR, drv_data->clear_sr);
1080
1081 pxa2xx_spi_dma_start(drv_data);
1082 } else {
1083 /* Ensure we have the correct interrupt handler */
1084 drv_data->transfer_handler = interrupt_transfer;
1085
1086 /* Clear status */
1087 cr1 = chip->cr1 | chip->threshold | drv_data->int_cr1;
1088 write_SSSR_CS(drv_data, drv_data->clear_sr);
1089 }
1090
1091 /* NOTE: PXA25x_SSP _could_ use external clocking ... */
1092 cr0 = pxa2xx_configure_sscr0(drv_data, clk_div, bits);
1093 if (!pxa25x_ssp_comp(drv_data))
1094 dev_dbg(&message->spi->dev, "%u Hz actual, %s\n",
1095 master->max_speed_hz
1096 / (1 + ((cr0 & SSCR0_SCR(0xfff)) >> 8)),
1097 dma_mapped ? "DMA" : "PIO");
1098 else
1099 dev_dbg(&message->spi->dev, "%u Hz actual, %s\n",
1100 master->max_speed_hz / 2
1101 / (1 + ((cr0 & SSCR0_SCR(0x0ff)) >> 8)),
1102 dma_mapped ? "DMA" : "PIO");
1103
1104 if (is_lpss_ssp(drv_data)) {
1105 if ((pxa2xx_spi_read(drv_data, SSIRF) & 0xff)
1106 != chip->lpss_rx_threshold)
1107 pxa2xx_spi_write(drv_data, SSIRF,
1108 chip->lpss_rx_threshold);
1109 if ((pxa2xx_spi_read(drv_data, SSITF) & 0xffff)
1110 != chip->lpss_tx_threshold)
1111 pxa2xx_spi_write(drv_data, SSITF,
1112 chip->lpss_tx_threshold);
1113 }
1114
1115 if (is_quark_x1000_ssp(drv_data) &&
1116 (pxa2xx_spi_read(drv_data, DDS_RATE) != chip->dds_rate))
1117 pxa2xx_spi_write(drv_data, DDS_RATE, chip->dds_rate);
1118
1119 /* see if we need to reload the config registers */
1120 if ((pxa2xx_spi_read(drv_data, SSCR0) != cr0)
1121 || (pxa2xx_spi_read(drv_data, SSCR1) & change_mask)
1122 != (cr1 & change_mask)) {
1123 /* stop the SSP, and update the other bits */
1124 pxa2xx_spi_write(drv_data, SSCR0, cr0 & ~SSCR0_SSE);
1125 if (!pxa25x_ssp_comp(drv_data))
1126 pxa2xx_spi_write(drv_data, SSTO, chip->timeout);
1127 /* first set CR1 without interrupt and service enables */
1128 pxa2xx_spi_write(drv_data, SSCR1, cr1 & change_mask);
1129 /* restart the SSP */
1130 pxa2xx_spi_write(drv_data, SSCR0, cr0);
1131
1132 } else {
1133 if (!pxa25x_ssp_comp(drv_data))
1134 pxa2xx_spi_write(drv_data, SSTO, chip->timeout);
1135 }
1136
1137 cs_assert(drv_data);
1138
1139 /* after chip select, release the data by enabling service
1140 * requests and interrupts, without changing any mode bits */
1141 pxa2xx_spi_write(drv_data, SSCR1, cr1);
1142 }
1143
1144 static int pxa2xx_spi_transfer_one_message(struct spi_master *master,
1145 struct spi_message *msg)
1146 {
1147 struct driver_data *drv_data = spi_master_get_devdata(master);
1148
1149 drv_data->cur_msg = msg;
1150 /* Initial message state*/
1151 drv_data->cur_msg->state = START_STATE;
1152 drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
1153 struct spi_transfer,
1154 transfer_list);
1155
1156 /* prepare to setup the SSP, in pump_transfers, using the per
1157 * chip configuration */
1158 drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
1159
1160 /* Mark as busy and launch transfers */
1161 tasklet_schedule(&drv_data->pump_transfers);
1162 return 0;
1163 }
1164
1165 static int pxa2xx_spi_unprepare_transfer(struct spi_master *master)
1166 {
1167 struct driver_data *drv_data = spi_master_get_devdata(master);
1168
1169 /* Disable the SSP now */
1170 pxa2xx_spi_write(drv_data, SSCR0,
1171 pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
1172
1173 return 0;
1174 }
1175
1176 static int setup_cs(struct spi_device *spi, struct chip_data *chip,
1177 struct pxa2xx_spi_chip *chip_info)
1178 {
1179 int err = 0;
1180
1181 if (chip == NULL || chip_info == NULL)
1182 return 0;
1183
1184 /* NOTE: setup() can be called multiple times, possibly with
1185 * different chip_info, release previously requested GPIO
1186 */
1187 if (gpio_is_valid(chip->gpio_cs))
1188 gpio_free(chip->gpio_cs);
1189
1190 /* If (*cs_control) is provided, ignore GPIO chip select */
1191 if (chip_info->cs_control) {
1192 chip->cs_control = chip_info->cs_control;
1193 return 0;
1194 }
1195
1196 if (gpio_is_valid(chip_info->gpio_cs)) {
1197 err = gpio_request(chip_info->gpio_cs, "SPI_CS");
1198 if (err) {
1199 dev_err(&spi->dev, "failed to request chip select GPIO%d\n",
1200 chip_info->gpio_cs);
1201 return err;
1202 }
1203
1204 chip->gpio_cs = chip_info->gpio_cs;
1205 chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH;
1206
1207 err = gpio_direction_output(chip->gpio_cs,
1208 !chip->gpio_cs_inverted);
1209 }
1210
1211 return err;
1212 }
1213
1214 static int setup(struct spi_device *spi)
1215 {
1216 struct pxa2xx_spi_chip *chip_info = NULL;
1217 struct chip_data *chip;
1218 const struct lpss_config *config;
1219 struct driver_data *drv_data = spi_master_get_devdata(spi->master);
1220 uint tx_thres, tx_hi_thres, rx_thres;
1221
1222 switch (drv_data->ssp_type) {
1223 case QUARK_X1000_SSP:
1224 tx_thres = TX_THRESH_QUARK_X1000_DFLT;
1225 tx_hi_thres = 0;
1226 rx_thres = RX_THRESH_QUARK_X1000_DFLT;
1227 break;
1228 case LPSS_LPT_SSP:
1229 case LPSS_BYT_SSP:
1230 case LPSS_BSW_SSP:
1231 case LPSS_SPT_SSP:
1232 case LPSS_BXT_SSP:
1233 config = lpss_get_config(drv_data);
1234 tx_thres = config->tx_threshold_lo;
1235 tx_hi_thres = config->tx_threshold_hi;
1236 rx_thres = config->rx_threshold;
1237 break;
1238 default:
1239 tx_thres = TX_THRESH_DFLT;
1240 tx_hi_thres = 0;
1241 rx_thres = RX_THRESH_DFLT;
1242 break;
1243 }
1244
1245 /* Only alloc on first setup */
1246 chip = spi_get_ctldata(spi);
1247 if (!chip) {
1248 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1249 if (!chip)
1250 return -ENOMEM;
1251
1252 if (drv_data->ssp_type == CE4100_SSP) {
1253 if (spi->chip_select > 4) {
1254 dev_err(&spi->dev,
1255 "failed setup: cs number must not be > 4.\n");
1256 kfree(chip);
1257 return -EINVAL;
1258 }
1259
1260 chip->frm = spi->chip_select;
1261 } else
1262 chip->gpio_cs = -1;
1263 chip->enable_dma = drv_data->master_info->enable_dma;
1264 chip->timeout = TIMOUT_DFLT;
1265 }
1266
1267 /* protocol drivers may change the chip settings, so...
1268 * if chip_info exists, use it */
1269 chip_info = spi->controller_data;
1270
1271 /* chip_info isn't always needed */
1272 chip->cr1 = 0;
1273 if (chip_info) {
1274 if (chip_info->timeout)
1275 chip->timeout = chip_info->timeout;
1276 if (chip_info->tx_threshold)
1277 tx_thres = chip_info->tx_threshold;
1278 if (chip_info->tx_hi_threshold)
1279 tx_hi_thres = chip_info->tx_hi_threshold;
1280 if (chip_info->rx_threshold)
1281 rx_thres = chip_info->rx_threshold;
1282 chip->dma_threshold = 0;
1283 if (chip_info->enable_loopback)
1284 chip->cr1 = SSCR1_LBM;
1285 }
1286
1287 chip->lpss_rx_threshold = SSIRF_RxThresh(rx_thres);
1288 chip->lpss_tx_threshold = SSITF_TxLoThresh(tx_thres)
1289 | SSITF_TxHiThresh(tx_hi_thres);
1290
1291 /* set dma burst and threshold outside of chip_info path so that if
1292 * chip_info goes away after setting chip->enable_dma, the
1293 * burst and threshold can still respond to changes in bits_per_word */
1294 if (chip->enable_dma) {
1295 /* set up legal burst and threshold for dma */
1296 if (pxa2xx_spi_set_dma_burst_and_threshold(chip, spi,
1297 spi->bits_per_word,
1298 &chip->dma_burst_size,
1299 &chip->dma_threshold)) {
1300 dev_warn(&spi->dev,
1301 "in setup: DMA burst size reduced to match bits_per_word\n");
1302 }
1303 }
1304
1305 switch (drv_data->ssp_type) {
1306 case QUARK_X1000_SSP:
1307 chip->threshold = (QUARK_X1000_SSCR1_RxTresh(rx_thres)
1308 & QUARK_X1000_SSCR1_RFT)
1309 | (QUARK_X1000_SSCR1_TxTresh(tx_thres)
1310 & QUARK_X1000_SSCR1_TFT);
1311 break;
1312 default:
1313 chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) |
1314 (SSCR1_TxTresh(tx_thres) & SSCR1_TFT);
1315 break;
1316 }
1317
1318 chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH);
1319 chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0)
1320 | (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0);
1321
1322 if (spi->mode & SPI_LOOP)
1323 chip->cr1 |= SSCR1_LBM;
1324
1325 if (spi->bits_per_word <= 8) {
1326 chip->n_bytes = 1;
1327 chip->read = u8_reader;
1328 chip->write = u8_writer;
1329 } else if (spi->bits_per_word <= 16) {
1330 chip->n_bytes = 2;
1331 chip->read = u16_reader;
1332 chip->write = u16_writer;
1333 } else if (spi->bits_per_word <= 32) {
1334 chip->n_bytes = 4;
1335 chip->read = u32_reader;
1336 chip->write = u32_writer;
1337 }
1338
1339 spi_set_ctldata(spi, chip);
1340
1341 if (drv_data->ssp_type == CE4100_SSP)
1342 return 0;
1343
1344 return setup_cs(spi, chip, chip_info);
1345 }
1346
1347 static void cleanup(struct spi_device *spi)
1348 {
1349 struct chip_data *chip = spi_get_ctldata(spi);
1350 struct driver_data *drv_data = spi_master_get_devdata(spi->master);
1351
1352 if (!chip)
1353 return;
1354
1355 if (drv_data->ssp_type != CE4100_SSP && gpio_is_valid(chip->gpio_cs))
1356 gpio_free(chip->gpio_cs);
1357
1358 kfree(chip);
1359 }
1360
1361 #ifdef CONFIG_PCI
1362 #ifdef CONFIG_ACPI
1363
1364 static const struct acpi_device_id pxa2xx_spi_acpi_match[] = {
1365 { "INT33C0", LPSS_LPT_SSP },
1366 { "INT33C1", LPSS_LPT_SSP },
1367 { "INT3430", LPSS_LPT_SSP },
1368 { "INT3431", LPSS_LPT_SSP },
1369 { "80860F0E", LPSS_BYT_SSP },
1370 { "8086228E", LPSS_BSW_SSP },
1371 { },
1372 };
1373 MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match);
1374
1375 static int pxa2xx_spi_get_port_id(struct acpi_device *adev)
1376 {
1377 unsigned int devid;
1378 int port_id = -1;
1379
1380 if (adev && adev->pnp.unique_id &&
1381 !kstrtouint(adev->pnp.unique_id, 0, &devid))
1382 port_id = devid;
1383 return port_id;
1384 }
1385 #else /* !CONFIG_ACPI */
1386 static int pxa2xx_spi_get_port_id(struct acpi_device *adev)
1387 {
1388 return -1;
1389 }
1390 #endif
1391
1392 /*
1393 * PCI IDs of compound devices that integrate both host controller and private
1394 * integrated DMA engine. Please note these are not used in module
1395 * autoloading and probing in this module but matching the LPSS SSP type.
1396 */
1397 static const struct pci_device_id pxa2xx_spi_pci_compound_match[] = {
1398 /* SPT-LP */
1399 { PCI_VDEVICE(INTEL, 0x9d29), LPSS_SPT_SSP },
1400 { PCI_VDEVICE(INTEL, 0x9d2a), LPSS_SPT_SSP },
1401 /* SPT-H */
1402 { PCI_VDEVICE(INTEL, 0xa129), LPSS_SPT_SSP },
1403 { PCI_VDEVICE(INTEL, 0xa12a), LPSS_SPT_SSP },
1404 /* KBL-H */
1405 { PCI_VDEVICE(INTEL, 0xa2a9), LPSS_SPT_SSP },
1406 { PCI_VDEVICE(INTEL, 0xa2aa), LPSS_SPT_SSP },
1407 /* BXT A-Step */
1408 { PCI_VDEVICE(INTEL, 0x0ac2), LPSS_BXT_SSP },
1409 { PCI_VDEVICE(INTEL, 0x0ac4), LPSS_BXT_SSP },
1410 { PCI_VDEVICE(INTEL, 0x0ac6), LPSS_BXT_SSP },
1411 /* BXT B-Step */
1412 { PCI_VDEVICE(INTEL, 0x1ac2), LPSS_BXT_SSP },
1413 { PCI_VDEVICE(INTEL, 0x1ac4), LPSS_BXT_SSP },
1414 { PCI_VDEVICE(INTEL, 0x1ac6), LPSS_BXT_SSP },
1415 /* APL */
1416 { PCI_VDEVICE(INTEL, 0x5ac2), LPSS_BXT_SSP },
1417 { PCI_VDEVICE(INTEL, 0x5ac4), LPSS_BXT_SSP },
1418 { PCI_VDEVICE(INTEL, 0x5ac6), LPSS_BXT_SSP },
1419 { },
1420 };
1421
1422 static bool pxa2xx_spi_idma_filter(struct dma_chan *chan, void *param)
1423 {
1424 struct device *dev = param;
1425
1426 if (dev != chan->device->dev->parent)
1427 return false;
1428
1429 return true;
1430 }
1431
1432 static struct pxa2xx_spi_master *
1433 pxa2xx_spi_init_pdata(struct platform_device *pdev)
1434 {
1435 struct pxa2xx_spi_master *pdata;
1436 struct acpi_device *adev;
1437 struct ssp_device *ssp;
1438 struct resource *res;
1439 const struct acpi_device_id *adev_id = NULL;
1440 const struct pci_device_id *pcidev_id = NULL;
1441 int type;
1442
1443 adev = ACPI_COMPANION(&pdev->dev);
1444
1445 if (dev_is_pci(pdev->dev.parent))
1446 pcidev_id = pci_match_id(pxa2xx_spi_pci_compound_match,
1447 to_pci_dev(pdev->dev.parent));
1448 else if (adev)
1449 adev_id = acpi_match_device(pdev->dev.driver->acpi_match_table,
1450 &pdev->dev);
1451 else
1452 return NULL;
1453
1454 if (adev_id)
1455 type = (int)adev_id->driver_data;
1456 else if (pcidev_id)
1457 type = (int)pcidev_id->driver_data;
1458 else
1459 return NULL;
1460
1461 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
1462 if (!pdata)
1463 return NULL;
1464
1465 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1466 if (!res)
1467 return NULL;
1468
1469 ssp = &pdata->ssp;
1470
1471 ssp->phys_base = res->start;
1472 ssp->mmio_base = devm_ioremap_resource(&pdev->dev, res);
1473 if (IS_ERR(ssp->mmio_base))
1474 return NULL;
1475
1476 if (pcidev_id) {
1477 pdata->tx_param = pdev->dev.parent;
1478 pdata->rx_param = pdev->dev.parent;
1479 pdata->dma_filter = pxa2xx_spi_idma_filter;
1480 }
1481
1482 ssp->clk = devm_clk_get(&pdev->dev, NULL);
1483 ssp->irq = platform_get_irq(pdev, 0);
1484 ssp->type = type;
1485 ssp->pdev = pdev;
1486 ssp->port_id = pxa2xx_spi_get_port_id(adev);
1487
1488 pdata->num_chipselect = 1;
1489 pdata->enable_dma = true;
1490
1491 return pdata;
1492 }
1493
1494 #else /* !CONFIG_PCI */
1495 static inline struct pxa2xx_spi_master *
1496 pxa2xx_spi_init_pdata(struct platform_device *pdev)
1497 {
1498 return NULL;
1499 }
1500 #endif
1501
1502 static int pxa2xx_spi_fw_translate_cs(struct spi_master *master, unsigned cs)
1503 {
1504 struct driver_data *drv_data = spi_master_get_devdata(master);
1505
1506 if (has_acpi_companion(&drv_data->pdev->dev)) {
1507 switch (drv_data->ssp_type) {
1508 /*
1509 * For Atoms the ACPI DeviceSelection used by the Windows
1510 * driver starts from 1 instead of 0 so translate it here
1511 * to match what Linux expects.
1512 */
1513 case LPSS_BYT_SSP:
1514 case LPSS_BSW_SSP:
1515 return cs - 1;
1516
1517 default:
1518 break;
1519 }
1520 }
1521
1522 return cs;
1523 }
1524
1525 static int pxa2xx_spi_probe(struct platform_device *pdev)
1526 {
1527 struct device *dev = &pdev->dev;
1528 struct pxa2xx_spi_master *platform_info;
1529 struct spi_master *master;
1530 struct driver_data *drv_data;
1531 struct ssp_device *ssp;
1532 const struct lpss_config *config;
1533 int status;
1534 u32 tmp;
1535
1536 platform_info = dev_get_platdata(dev);
1537 if (!platform_info) {
1538 platform_info = pxa2xx_spi_init_pdata(pdev);
1539 if (!platform_info) {
1540 dev_err(&pdev->dev, "missing platform data\n");
1541 return -ENODEV;
1542 }
1543 }
1544
1545 ssp = pxa_ssp_request(pdev->id, pdev->name);
1546 if (!ssp)
1547 ssp = &platform_info->ssp;
1548
1549 if (!ssp->mmio_base) {
1550 dev_err(&pdev->dev, "failed to get ssp\n");
1551 return -ENODEV;
1552 }
1553
1554 master = spi_alloc_master(dev, sizeof(struct driver_data));
1555 if (!master) {
1556 dev_err(&pdev->dev, "cannot alloc spi_master\n");
1557 pxa_ssp_free(ssp);
1558 return -ENOMEM;
1559 }
1560 drv_data = spi_master_get_devdata(master);
1561 drv_data->master = master;
1562 drv_data->master_info = platform_info;
1563 drv_data->pdev = pdev;
1564 drv_data->ssp = ssp;
1565
1566 master->dev.of_node = pdev->dev.of_node;
1567 /* the spi->mode bits understood by this driver: */
1568 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
1569
1570 master->bus_num = ssp->port_id;
1571 master->dma_alignment = DMA_ALIGNMENT;
1572 master->cleanup = cleanup;
1573 master->setup = setup;
1574 master->transfer_one_message = pxa2xx_spi_transfer_one_message;
1575 master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer;
1576 master->fw_translate_cs = pxa2xx_spi_fw_translate_cs;
1577 master->auto_runtime_pm = true;
1578 master->flags = SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX;
1579
1580 drv_data->ssp_type = ssp->type;
1581
1582 drv_data->ioaddr = ssp->mmio_base;
1583 drv_data->ssdr_physical = ssp->phys_base + SSDR;
1584 if (pxa25x_ssp_comp(drv_data)) {
1585 switch (drv_data->ssp_type) {
1586 case QUARK_X1000_SSP:
1587 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1588 break;
1589 default:
1590 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
1591 break;
1592 }
1593
1594 drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE;
1595 drv_data->dma_cr1 = 0;
1596 drv_data->clear_sr = SSSR_ROR;
1597 drv_data->mask_sr = SSSR_RFS | SSSR_TFS | SSSR_ROR;
1598 } else {
1599 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1600 drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE | SSCR1_TINTE;
1601 drv_data->dma_cr1 = DEFAULT_DMA_CR1;
1602 drv_data->clear_sr = SSSR_ROR | SSSR_TINT;
1603 drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS | SSSR_ROR;
1604 }
1605
1606 status = request_irq(ssp->irq, ssp_int, IRQF_SHARED, dev_name(dev),
1607 drv_data);
1608 if (status < 0) {
1609 dev_err(&pdev->dev, "cannot get IRQ %d\n", ssp->irq);
1610 goto out_error_master_alloc;
1611 }
1612
1613 /* Setup DMA if requested */
1614 if (platform_info->enable_dma) {
1615 status = pxa2xx_spi_dma_setup(drv_data);
1616 if (status) {
1617 dev_dbg(dev, "no DMA channels available, using PIO\n");
1618 platform_info->enable_dma = false;
1619 } else {
1620 master->can_dma = pxa2xx_spi_can_dma;
1621 }
1622 }
1623
1624 /* Enable SOC clock */
1625 clk_prepare_enable(ssp->clk);
1626
1627 master->max_speed_hz = clk_get_rate(ssp->clk);
1628
1629 /* Load default SSP configuration */
1630 pxa2xx_spi_write(drv_data, SSCR0, 0);
1631 switch (drv_data->ssp_type) {
1632 case QUARK_X1000_SSP:
1633 tmp = QUARK_X1000_SSCR1_RxTresh(RX_THRESH_QUARK_X1000_DFLT)
1634 | QUARK_X1000_SSCR1_TxTresh(TX_THRESH_QUARK_X1000_DFLT);
1635 pxa2xx_spi_write(drv_data, SSCR1, tmp);
1636
1637 /* using the Motorola SPI protocol and use 8 bit frame */
1638 pxa2xx_spi_write(drv_data, SSCR0,
1639 QUARK_X1000_SSCR0_Motorola
1640 | QUARK_X1000_SSCR0_DataSize(8));
1641 break;
1642 default:
1643 tmp = SSCR1_RxTresh(RX_THRESH_DFLT) |
1644 SSCR1_TxTresh(TX_THRESH_DFLT);
1645 pxa2xx_spi_write(drv_data, SSCR1, tmp);
1646 tmp = SSCR0_SCR(2) | SSCR0_Motorola | SSCR0_DataSize(8);
1647 pxa2xx_spi_write(drv_data, SSCR0, tmp);
1648 break;
1649 }
1650
1651 if (!pxa25x_ssp_comp(drv_data))
1652 pxa2xx_spi_write(drv_data, SSTO, 0);
1653
1654 if (!is_quark_x1000_ssp(drv_data))
1655 pxa2xx_spi_write(drv_data, SSPSP, 0);
1656
1657 if (is_lpss_ssp(drv_data)) {
1658 lpss_ssp_setup(drv_data);
1659 config = lpss_get_config(drv_data);
1660 if (config->reg_capabilities >= 0) {
1661 tmp = __lpss_ssp_read_priv(drv_data,
1662 config->reg_capabilities);
1663 tmp &= LPSS_CAPS_CS_EN_MASK;
1664 tmp >>= LPSS_CAPS_CS_EN_SHIFT;
1665 platform_info->num_chipselect = ffz(tmp);
1666 } else if (config->cs_num) {
1667 platform_info->num_chipselect = config->cs_num;
1668 }
1669 }
1670 master->num_chipselect = platform_info->num_chipselect;
1671
1672 tasklet_init(&drv_data->pump_transfers, pump_transfers,
1673 (unsigned long)drv_data);
1674
1675 pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
1676 pm_runtime_use_autosuspend(&pdev->dev);
1677 pm_runtime_set_active(&pdev->dev);
1678 pm_runtime_enable(&pdev->dev);
1679
1680 /* Register with the SPI framework */
1681 platform_set_drvdata(pdev, drv_data);
1682 status = devm_spi_register_master(&pdev->dev, master);
1683 if (status != 0) {
1684 dev_err(&pdev->dev, "problem registering spi master\n");
1685 goto out_error_clock_enabled;
1686 }
1687
1688 return status;
1689
1690 out_error_clock_enabled:
1691 clk_disable_unprepare(ssp->clk);
1692 pxa2xx_spi_dma_release(drv_data);
1693 free_irq(ssp->irq, drv_data);
1694
1695 out_error_master_alloc:
1696 spi_master_put(master);
1697 pxa_ssp_free(ssp);
1698 return status;
1699 }
1700
1701 static int pxa2xx_spi_remove(struct platform_device *pdev)
1702 {
1703 struct driver_data *drv_data = platform_get_drvdata(pdev);
1704 struct ssp_device *ssp;
1705
1706 if (!drv_data)
1707 return 0;
1708 ssp = drv_data->ssp;
1709
1710 pm_runtime_get_sync(&pdev->dev);
1711
1712 /* Disable the SSP at the peripheral and SOC level */
1713 pxa2xx_spi_write(drv_data, SSCR0, 0);
1714 clk_disable_unprepare(ssp->clk);
1715
1716 /* Release DMA */
1717 if (drv_data->master_info->enable_dma)
1718 pxa2xx_spi_dma_release(drv_data);
1719
1720 pm_runtime_put_noidle(&pdev->dev);
1721 pm_runtime_disable(&pdev->dev);
1722
1723 /* Release IRQ */
1724 free_irq(ssp->irq, drv_data);
1725
1726 /* Release SSP */
1727 pxa_ssp_free(ssp);
1728
1729 return 0;
1730 }
1731
1732 static void pxa2xx_spi_shutdown(struct platform_device *pdev)
1733 {
1734 int status = 0;
1735
1736 if ((status = pxa2xx_spi_remove(pdev)) != 0)
1737 dev_err(&pdev->dev, "shutdown failed with %d\n", status);
1738 }
1739
1740 #ifdef CONFIG_PM_SLEEP
1741 static int pxa2xx_spi_suspend(struct device *dev)
1742 {
1743 struct driver_data *drv_data = dev_get_drvdata(dev);
1744 struct ssp_device *ssp = drv_data->ssp;
1745 int status = 0;
1746
1747 status = spi_master_suspend(drv_data->master);
1748 if (status != 0)
1749 return status;
1750 pxa2xx_spi_write(drv_data, SSCR0, 0);
1751
1752 if (!pm_runtime_suspended(dev))
1753 clk_disable_unprepare(ssp->clk);
1754
1755 return 0;
1756 }
1757
1758 static int pxa2xx_spi_resume(struct device *dev)
1759 {
1760 struct driver_data *drv_data = dev_get_drvdata(dev);
1761 struct ssp_device *ssp = drv_data->ssp;
1762 int status = 0;
1763
1764 /* Enable the SSP clock */
1765 if (!pm_runtime_suspended(dev))
1766 clk_prepare_enable(ssp->clk);
1767
1768 /* Restore LPSS private register bits */
1769 if (is_lpss_ssp(drv_data))
1770 lpss_ssp_setup(drv_data);
1771
1772 /* Start the queue running */
1773 status = spi_master_resume(drv_data->master);
1774 if (status != 0) {
1775 dev_err(dev, "problem starting queue (%d)\n", status);
1776 return status;
1777 }
1778
1779 return 0;
1780 }
1781 #endif
1782
1783 #ifdef CONFIG_PM
1784 static int pxa2xx_spi_runtime_suspend(struct device *dev)
1785 {
1786 struct driver_data *drv_data = dev_get_drvdata(dev);
1787
1788 clk_disable_unprepare(drv_data->ssp->clk);
1789 return 0;
1790 }
1791
1792 static int pxa2xx_spi_runtime_resume(struct device *dev)
1793 {
1794 struct driver_data *drv_data = dev_get_drvdata(dev);
1795
1796 clk_prepare_enable(drv_data->ssp->clk);
1797 return 0;
1798 }
1799 #endif
1800
1801 static const struct dev_pm_ops pxa2xx_spi_pm_ops = {
1802 SET_SYSTEM_SLEEP_PM_OPS(pxa2xx_spi_suspend, pxa2xx_spi_resume)
1803 SET_RUNTIME_PM_OPS(pxa2xx_spi_runtime_suspend,
1804 pxa2xx_spi_runtime_resume, NULL)
1805 };
1806
1807 static struct platform_driver driver = {
1808 .driver = {
1809 .name = "pxa2xx-spi",
1810 .pm = &pxa2xx_spi_pm_ops,
1811 .acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match),
1812 },
1813 .probe = pxa2xx_spi_probe,
1814 .remove = pxa2xx_spi_remove,
1815 .shutdown = pxa2xx_spi_shutdown,
1816 };
1817
1818 static int __init pxa2xx_spi_init(void)
1819 {
1820 return platform_driver_register(&driver);
1821 }
1822 subsys_initcall(pxa2xx_spi_init);
1823
1824 static void __exit pxa2xx_spi_exit(void)
1825 {
1826 platform_driver_unregister(&driver);
1827 }
1828 module_exit(pxa2xx_spi_exit);
Linux kernel - Deliverables
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