Linux 4.16.11
[linux/fpc-iii.git] / drivers / spi / spi-pxa2xx.c
blobb0822d1dba298fced70045495f48f33d49db8ca3
1 /*
2 * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
3 * Copyright (C) 2013, Intel Corporation
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.
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.
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/gpio/consumer.h>
32 #include <linux/slab.h>
33 #include <linux/clk.h>
34 #include <linux/pm_runtime.h>
35 #include <linux/acpi.h>
37 #include "spi-pxa2xx.h"
39 MODULE_AUTHOR("Stephen Street");
40 MODULE_DESCRIPTION("PXA2xx SSP SPI Controller");
41 MODULE_LICENSE("GPL");
42 MODULE_ALIAS("platform:pxa2xx-spi");
44 #define TIMOUT_DFLT 1000
47 * for testing SSCR1 changes that require SSP restart, basically
48 * everything except the service and interrupt enables, the pxa270 developer
49 * manual says only SSCR1_SCFR, SSCR1_SPH, SSCR1_SPO need to be in this
50 * list, but the PXA255 dev man says all bits without really meaning the
51 * service and interrupt enables
53 #define SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_SCFR \
54 | SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \
55 | SSCR1_SFRMDIR | SSCR1_RWOT | SSCR1_TRAIL \
56 | SSCR1_IFS | SSCR1_STRF | SSCR1_EFWR \
57 | SSCR1_RFT | SSCR1_TFT | SSCR1_MWDS \
58 | SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
60 #define QUARK_X1000_SSCR1_CHANGE_MASK (QUARK_X1000_SSCR1_STRF \
61 | QUARK_X1000_SSCR1_EFWR \
62 | QUARK_X1000_SSCR1_RFT \
63 | QUARK_X1000_SSCR1_TFT \
64 | SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
66 #define CE4100_SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_SCFR \
67 | SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \
68 | SSCR1_SFRMDIR | SSCR1_RWOT | SSCR1_TRAIL \
69 | SSCR1_IFS | SSCR1_STRF | SSCR1_EFWR \
70 | CE4100_SSCR1_RFT | CE4100_SSCR1_TFT | SSCR1_MWDS \
71 | SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
73 #define LPSS_GENERAL_REG_RXTO_HOLDOFF_DISABLE BIT(24)
74 #define LPSS_CS_CONTROL_SW_MODE BIT(0)
75 #define LPSS_CS_CONTROL_CS_HIGH BIT(1)
76 #define LPSS_CAPS_CS_EN_SHIFT 9
77 #define LPSS_CAPS_CS_EN_MASK (0xf << LPSS_CAPS_CS_EN_SHIFT)
79 struct lpss_config {
80 /* LPSS offset from drv_data->ioaddr */
81 unsigned offset;
82 /* Register offsets from drv_data->lpss_base or -1 */
83 int reg_general;
84 int reg_ssp;
85 int reg_cs_ctrl;
86 int reg_capabilities;
87 /* FIFO thresholds */
88 u32 rx_threshold;
89 u32 tx_threshold_lo;
90 u32 tx_threshold_hi;
91 /* Chip select control */
92 unsigned cs_sel_shift;
93 unsigned cs_sel_mask;
94 unsigned cs_num;
97 /* Keep these sorted with enum pxa_ssp_type */
98 static const struct lpss_config lpss_platforms[] = {
99 { /* LPSS_LPT_SSP */
100 .offset = 0x800,
101 .reg_general = 0x08,
102 .reg_ssp = 0x0c,
103 .reg_cs_ctrl = 0x18,
104 .reg_capabilities = -1,
105 .rx_threshold = 64,
106 .tx_threshold_lo = 160,
107 .tx_threshold_hi = 224,
109 { /* LPSS_BYT_SSP */
110 .offset = 0x400,
111 .reg_general = 0x08,
112 .reg_ssp = 0x0c,
113 .reg_cs_ctrl = 0x18,
114 .reg_capabilities = -1,
115 .rx_threshold = 64,
116 .tx_threshold_lo = 160,
117 .tx_threshold_hi = 224,
119 { /* LPSS_BSW_SSP */
120 .offset = 0x400,
121 .reg_general = 0x08,
122 .reg_ssp = 0x0c,
123 .reg_cs_ctrl = 0x18,
124 .reg_capabilities = -1,
125 .rx_threshold = 64,
126 .tx_threshold_lo = 160,
127 .tx_threshold_hi = 224,
128 .cs_sel_shift = 2,
129 .cs_sel_mask = 1 << 2,
130 .cs_num = 2,
132 { /* LPSS_SPT_SSP */
133 .offset = 0x200,
134 .reg_general = -1,
135 .reg_ssp = 0x20,
136 .reg_cs_ctrl = 0x24,
137 .reg_capabilities = -1,
138 .rx_threshold = 1,
139 .tx_threshold_lo = 32,
140 .tx_threshold_hi = 56,
142 { /* LPSS_BXT_SSP */
143 .offset = 0x200,
144 .reg_general = -1,
145 .reg_ssp = 0x20,
146 .reg_cs_ctrl = 0x24,
147 .reg_capabilities = 0xfc,
148 .rx_threshold = 1,
149 .tx_threshold_lo = 16,
150 .tx_threshold_hi = 48,
151 .cs_sel_shift = 8,
152 .cs_sel_mask = 3 << 8,
154 { /* LPSS_CNL_SSP */
155 .offset = 0x200,
156 .reg_general = -1,
157 .reg_ssp = 0x20,
158 .reg_cs_ctrl = 0x24,
159 .reg_capabilities = 0xfc,
160 .rx_threshold = 1,
161 .tx_threshold_lo = 32,
162 .tx_threshold_hi = 56,
163 .cs_sel_shift = 8,
164 .cs_sel_mask = 3 << 8,
168 static inline const struct lpss_config
169 *lpss_get_config(const struct driver_data *drv_data)
171 return &lpss_platforms[drv_data->ssp_type - LPSS_LPT_SSP];
174 static bool is_lpss_ssp(const struct driver_data *drv_data)
176 switch (drv_data->ssp_type) {
177 case LPSS_LPT_SSP:
178 case LPSS_BYT_SSP:
179 case LPSS_BSW_SSP:
180 case LPSS_SPT_SSP:
181 case LPSS_BXT_SSP:
182 case LPSS_CNL_SSP:
183 return true;
184 default:
185 return false;
189 static bool is_quark_x1000_ssp(const struct driver_data *drv_data)
191 return drv_data->ssp_type == QUARK_X1000_SSP;
194 static u32 pxa2xx_spi_get_ssrc1_change_mask(const struct driver_data *drv_data)
196 switch (drv_data->ssp_type) {
197 case QUARK_X1000_SSP:
198 return QUARK_X1000_SSCR1_CHANGE_MASK;
199 case CE4100_SSP:
200 return CE4100_SSCR1_CHANGE_MASK;
201 default:
202 return SSCR1_CHANGE_MASK;
206 static u32
207 pxa2xx_spi_get_rx_default_thre(const struct driver_data *drv_data)
209 switch (drv_data->ssp_type) {
210 case QUARK_X1000_SSP:
211 return RX_THRESH_QUARK_X1000_DFLT;
212 case CE4100_SSP:
213 return RX_THRESH_CE4100_DFLT;
214 default:
215 return RX_THRESH_DFLT;
219 static bool pxa2xx_spi_txfifo_full(const struct driver_data *drv_data)
221 u32 mask;
223 switch (drv_data->ssp_type) {
224 case QUARK_X1000_SSP:
225 mask = QUARK_X1000_SSSR_TFL_MASK;
226 break;
227 case CE4100_SSP:
228 mask = CE4100_SSSR_TFL_MASK;
229 break;
230 default:
231 mask = SSSR_TFL_MASK;
232 break;
235 return (pxa2xx_spi_read(drv_data, SSSR) & mask) == mask;
238 static void pxa2xx_spi_clear_rx_thre(const struct driver_data *drv_data,
239 u32 *sccr1_reg)
241 u32 mask;
243 switch (drv_data->ssp_type) {
244 case QUARK_X1000_SSP:
245 mask = QUARK_X1000_SSCR1_RFT;
246 break;
247 case CE4100_SSP:
248 mask = CE4100_SSCR1_RFT;
249 break;
250 default:
251 mask = SSCR1_RFT;
252 break;
254 *sccr1_reg &= ~mask;
257 static void pxa2xx_spi_set_rx_thre(const struct driver_data *drv_data,
258 u32 *sccr1_reg, u32 threshold)
260 switch (drv_data->ssp_type) {
261 case QUARK_X1000_SSP:
262 *sccr1_reg |= QUARK_X1000_SSCR1_RxTresh(threshold);
263 break;
264 case CE4100_SSP:
265 *sccr1_reg |= CE4100_SSCR1_RxTresh(threshold);
266 break;
267 default:
268 *sccr1_reg |= SSCR1_RxTresh(threshold);
269 break;
273 static u32 pxa2xx_configure_sscr0(const struct driver_data *drv_data,
274 u32 clk_div, u8 bits)
276 switch (drv_data->ssp_type) {
277 case QUARK_X1000_SSP:
278 return clk_div
279 | QUARK_X1000_SSCR0_Motorola
280 | QUARK_X1000_SSCR0_DataSize(bits > 32 ? 8 : bits)
281 | SSCR0_SSE;
282 default:
283 return clk_div
284 | SSCR0_Motorola
285 | SSCR0_DataSize(bits > 16 ? bits - 16 : bits)
286 | SSCR0_SSE
287 | (bits > 16 ? SSCR0_EDSS : 0);
292 * Read and write LPSS SSP private registers. Caller must first check that
293 * is_lpss_ssp() returns true before these can be called.
295 static u32 __lpss_ssp_read_priv(struct driver_data *drv_data, unsigned offset)
297 WARN_ON(!drv_data->lpss_base);
298 return readl(drv_data->lpss_base + offset);
301 static void __lpss_ssp_write_priv(struct driver_data *drv_data,
302 unsigned offset, u32 value)
304 WARN_ON(!drv_data->lpss_base);
305 writel(value, drv_data->lpss_base + offset);
309 * lpss_ssp_setup - perform LPSS SSP specific setup
310 * @drv_data: pointer to the driver private data
312 * Perform LPSS SSP specific setup. This function must be called first if
313 * one is going to use LPSS SSP private registers.
315 static void lpss_ssp_setup(struct driver_data *drv_data)
317 const struct lpss_config *config;
318 u32 value;
320 config = lpss_get_config(drv_data);
321 drv_data->lpss_base = drv_data->ioaddr + config->offset;
323 /* Enable software chip select control */
324 value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
325 value &= ~(LPSS_CS_CONTROL_SW_MODE | LPSS_CS_CONTROL_CS_HIGH);
326 value |= LPSS_CS_CONTROL_SW_MODE | LPSS_CS_CONTROL_CS_HIGH;
327 __lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
329 /* Enable multiblock DMA transfers */
330 if (drv_data->master_info->enable_dma) {
331 __lpss_ssp_write_priv(drv_data, config->reg_ssp, 1);
333 if (config->reg_general >= 0) {
334 value = __lpss_ssp_read_priv(drv_data,
335 config->reg_general);
336 value |= LPSS_GENERAL_REG_RXTO_HOLDOFF_DISABLE;
337 __lpss_ssp_write_priv(drv_data,
338 config->reg_general, value);
343 static void lpss_ssp_select_cs(struct driver_data *drv_data,
344 const struct lpss_config *config)
346 u32 value, cs;
348 if (!config->cs_sel_mask)
349 return;
351 value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
353 cs = drv_data->master->cur_msg->spi->chip_select;
354 cs <<= config->cs_sel_shift;
355 if (cs != (value & config->cs_sel_mask)) {
357 * When switching another chip select output active the
358 * output must be selected first and wait 2 ssp_clk cycles
359 * before changing state to active. Otherwise a short
360 * glitch will occur on the previous chip select since
361 * output select is latched but state control is not.
363 value &= ~config->cs_sel_mask;
364 value |= cs;
365 __lpss_ssp_write_priv(drv_data,
366 config->reg_cs_ctrl, value);
367 ndelay(1000000000 /
368 (drv_data->master->max_speed_hz / 2));
372 static void lpss_ssp_cs_control(struct driver_data *drv_data, bool enable)
374 const struct lpss_config *config;
375 u32 value;
377 config = lpss_get_config(drv_data);
379 if (enable)
380 lpss_ssp_select_cs(drv_data, config);
382 value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
383 if (enable)
384 value &= ~LPSS_CS_CONTROL_CS_HIGH;
385 else
386 value |= LPSS_CS_CONTROL_CS_HIGH;
387 __lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
390 static void cs_assert(struct driver_data *drv_data)
392 struct chip_data *chip =
393 spi_get_ctldata(drv_data->master->cur_msg->spi);
395 if (drv_data->ssp_type == CE4100_SSP) {
396 pxa2xx_spi_write(drv_data, SSSR, chip->frm);
397 return;
400 if (chip->cs_control) {
401 chip->cs_control(PXA2XX_CS_ASSERT);
402 return;
405 if (chip->gpiod_cs) {
406 gpiod_set_value(chip->gpiod_cs, chip->gpio_cs_inverted);
407 return;
410 if (is_lpss_ssp(drv_data))
411 lpss_ssp_cs_control(drv_data, true);
414 static void cs_deassert(struct driver_data *drv_data)
416 struct chip_data *chip =
417 spi_get_ctldata(drv_data->master->cur_msg->spi);
419 if (drv_data->ssp_type == CE4100_SSP)
420 return;
422 if (chip->cs_control) {
423 chip->cs_control(PXA2XX_CS_DEASSERT);
424 return;
427 if (chip->gpiod_cs) {
428 gpiod_set_value(chip->gpiod_cs, !chip->gpio_cs_inverted);
429 return;
432 if (is_lpss_ssp(drv_data))
433 lpss_ssp_cs_control(drv_data, false);
436 int pxa2xx_spi_flush(struct driver_data *drv_data)
438 unsigned long limit = loops_per_jiffy << 1;
440 do {
441 while (pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
442 pxa2xx_spi_read(drv_data, SSDR);
443 } while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY) && --limit);
444 write_SSSR_CS(drv_data, SSSR_ROR);
446 return limit;
449 static int null_writer(struct driver_data *drv_data)
451 u8 n_bytes = drv_data->n_bytes;
453 if (pxa2xx_spi_txfifo_full(drv_data)
454 || (drv_data->tx == drv_data->tx_end))
455 return 0;
457 pxa2xx_spi_write(drv_data, SSDR, 0);
458 drv_data->tx += n_bytes;
460 return 1;
463 static int null_reader(struct driver_data *drv_data)
465 u8 n_bytes = drv_data->n_bytes;
467 while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
468 && (drv_data->rx < drv_data->rx_end)) {
469 pxa2xx_spi_read(drv_data, SSDR);
470 drv_data->rx += n_bytes;
473 return drv_data->rx == drv_data->rx_end;
476 static int u8_writer(struct driver_data *drv_data)
478 if (pxa2xx_spi_txfifo_full(drv_data)
479 || (drv_data->tx == drv_data->tx_end))
480 return 0;
482 pxa2xx_spi_write(drv_data, SSDR, *(u8 *)(drv_data->tx));
483 ++drv_data->tx;
485 return 1;
488 static int u8_reader(struct driver_data *drv_data)
490 while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
491 && (drv_data->rx < drv_data->rx_end)) {
492 *(u8 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
493 ++drv_data->rx;
496 return drv_data->rx == drv_data->rx_end;
499 static int u16_writer(struct driver_data *drv_data)
501 if (pxa2xx_spi_txfifo_full(drv_data)
502 || (drv_data->tx == drv_data->tx_end))
503 return 0;
505 pxa2xx_spi_write(drv_data, SSDR, *(u16 *)(drv_data->tx));
506 drv_data->tx += 2;
508 return 1;
511 static int u16_reader(struct driver_data *drv_data)
513 while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
514 && (drv_data->rx < drv_data->rx_end)) {
515 *(u16 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
516 drv_data->rx += 2;
519 return drv_data->rx == drv_data->rx_end;
522 static int u32_writer(struct driver_data *drv_data)
524 if (pxa2xx_spi_txfifo_full(drv_data)
525 || (drv_data->tx == drv_data->tx_end))
526 return 0;
528 pxa2xx_spi_write(drv_data, SSDR, *(u32 *)(drv_data->tx));
529 drv_data->tx += 4;
531 return 1;
534 static int u32_reader(struct driver_data *drv_data)
536 while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
537 && (drv_data->rx < drv_data->rx_end)) {
538 *(u32 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
539 drv_data->rx += 4;
542 return drv_data->rx == drv_data->rx_end;
545 void *pxa2xx_spi_next_transfer(struct driver_data *drv_data)
547 struct spi_message *msg = drv_data->master->cur_msg;
548 struct spi_transfer *trans = drv_data->cur_transfer;
550 /* Move to next transfer */
551 if (trans->transfer_list.next != &msg->transfers) {
552 drv_data->cur_transfer =
553 list_entry(trans->transfer_list.next,
554 struct spi_transfer,
555 transfer_list);
556 return RUNNING_STATE;
557 } else
558 return DONE_STATE;
561 /* caller already set message->status; dma and pio irqs are blocked */
562 static void giveback(struct driver_data *drv_data)
564 struct spi_transfer* last_transfer;
565 struct spi_message *msg;
566 unsigned long timeout;
568 msg = drv_data->master->cur_msg;
569 drv_data->cur_transfer = NULL;
571 last_transfer = list_last_entry(&msg->transfers, struct spi_transfer,
572 transfer_list);
574 /* Delay if requested before any change in chip select */
575 if (last_transfer->delay_usecs)
576 udelay(last_transfer->delay_usecs);
578 /* Wait until SSP becomes idle before deasserting the CS */
579 timeout = jiffies + msecs_to_jiffies(10);
580 while (pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY &&
581 !time_after(jiffies, timeout))
582 cpu_relax();
584 /* Drop chip select UNLESS cs_change is true or we are returning
585 * a message with an error, or next message is for another chip
587 if (!last_transfer->cs_change)
588 cs_deassert(drv_data);
589 else {
590 struct spi_message *next_msg;
592 /* Holding of cs was hinted, but we need to make sure
593 * the next message is for the same chip. Don't waste
594 * time with the following tests unless this was hinted.
596 * We cannot postpone this until pump_messages, because
597 * after calling msg->complete (below) the driver that
598 * sent the current message could be unloaded, which
599 * could invalidate the cs_control() callback...
602 /* get a pointer to the next message, if any */
603 next_msg = spi_get_next_queued_message(drv_data->master);
605 /* see if the next and current messages point
606 * to the same chip
608 if ((next_msg && next_msg->spi != msg->spi) ||
609 msg->state == ERROR_STATE)
610 cs_deassert(drv_data);
613 spi_finalize_current_message(drv_data->master);
616 static void reset_sccr1(struct driver_data *drv_data)
618 struct chip_data *chip =
619 spi_get_ctldata(drv_data->master->cur_msg->spi);
620 u32 sccr1_reg;
622 sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1) & ~drv_data->int_cr1;
623 switch (drv_data->ssp_type) {
624 case QUARK_X1000_SSP:
625 sccr1_reg &= ~QUARK_X1000_SSCR1_RFT;
626 break;
627 case CE4100_SSP:
628 sccr1_reg &= ~CE4100_SSCR1_RFT;
629 break;
630 default:
631 sccr1_reg &= ~SSCR1_RFT;
632 break;
634 sccr1_reg |= chip->threshold;
635 pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
638 static void int_error_stop(struct driver_data *drv_data, const char* msg)
640 /* Stop and reset SSP */
641 write_SSSR_CS(drv_data, drv_data->clear_sr);
642 reset_sccr1(drv_data);
643 if (!pxa25x_ssp_comp(drv_data))
644 pxa2xx_spi_write(drv_data, SSTO, 0);
645 pxa2xx_spi_flush(drv_data);
646 pxa2xx_spi_write(drv_data, SSCR0,
647 pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
649 dev_err(&drv_data->pdev->dev, "%s\n", msg);
651 drv_data->master->cur_msg->state = ERROR_STATE;
652 tasklet_schedule(&drv_data->pump_transfers);
655 static void int_transfer_complete(struct driver_data *drv_data)
657 /* Clear and disable interrupts */
658 write_SSSR_CS(drv_data, drv_data->clear_sr);
659 reset_sccr1(drv_data);
660 if (!pxa25x_ssp_comp(drv_data))
661 pxa2xx_spi_write(drv_data, SSTO, 0);
663 /* Update total byte transferred return count actual bytes read */
664 drv_data->master->cur_msg->actual_length += drv_data->len -
665 (drv_data->rx_end - drv_data->rx);
667 /* Transfer delays and chip select release are
668 * handled in pump_transfers or giveback
671 /* Move to next transfer */
672 drv_data->master->cur_msg->state = pxa2xx_spi_next_transfer(drv_data);
674 /* Schedule transfer tasklet */
675 tasklet_schedule(&drv_data->pump_transfers);
678 static irqreturn_t interrupt_transfer(struct driver_data *drv_data)
680 u32 irq_mask = (pxa2xx_spi_read(drv_data, SSCR1) & SSCR1_TIE) ?
681 drv_data->mask_sr : drv_data->mask_sr & ~SSSR_TFS;
683 u32 irq_status = pxa2xx_spi_read(drv_data, SSSR) & irq_mask;
685 if (irq_status & SSSR_ROR) {
686 int_error_stop(drv_data, "interrupt_transfer: fifo overrun");
687 return IRQ_HANDLED;
690 if (irq_status & SSSR_TINT) {
691 pxa2xx_spi_write(drv_data, SSSR, SSSR_TINT);
692 if (drv_data->read(drv_data)) {
693 int_transfer_complete(drv_data);
694 return IRQ_HANDLED;
698 /* Drain rx fifo, Fill tx fifo and prevent overruns */
699 do {
700 if (drv_data->read(drv_data)) {
701 int_transfer_complete(drv_data);
702 return IRQ_HANDLED;
704 } while (drv_data->write(drv_data));
706 if (drv_data->read(drv_data)) {
707 int_transfer_complete(drv_data);
708 return IRQ_HANDLED;
711 if (drv_data->tx == drv_data->tx_end) {
712 u32 bytes_left;
713 u32 sccr1_reg;
715 sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1);
716 sccr1_reg &= ~SSCR1_TIE;
719 * PXA25x_SSP has no timeout, set up rx threshould for the
720 * remaining RX bytes.
722 if (pxa25x_ssp_comp(drv_data)) {
723 u32 rx_thre;
725 pxa2xx_spi_clear_rx_thre(drv_data, &sccr1_reg);
727 bytes_left = drv_data->rx_end - drv_data->rx;
728 switch (drv_data->n_bytes) {
729 case 4:
730 bytes_left >>= 1;
731 case 2:
732 bytes_left >>= 1;
735 rx_thre = pxa2xx_spi_get_rx_default_thre(drv_data);
736 if (rx_thre > bytes_left)
737 rx_thre = bytes_left;
739 pxa2xx_spi_set_rx_thre(drv_data, &sccr1_reg, rx_thre);
741 pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
744 /* We did something */
745 return IRQ_HANDLED;
748 static void handle_bad_msg(struct driver_data *drv_data)
750 pxa2xx_spi_write(drv_data, SSCR0,
751 pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
752 pxa2xx_spi_write(drv_data, SSCR1,
753 pxa2xx_spi_read(drv_data, SSCR1) & ~drv_data->int_cr1);
754 if (!pxa25x_ssp_comp(drv_data))
755 pxa2xx_spi_write(drv_data, SSTO, 0);
756 write_SSSR_CS(drv_data, drv_data->clear_sr);
758 dev_err(&drv_data->pdev->dev,
759 "bad message state in interrupt handler\n");
762 static irqreturn_t ssp_int(int irq, void *dev_id)
764 struct driver_data *drv_data = dev_id;
765 u32 sccr1_reg;
766 u32 mask = drv_data->mask_sr;
767 u32 status;
770 * The IRQ might be shared with other peripherals so we must first
771 * check that are we RPM suspended or not. If we are we assume that
772 * the IRQ was not for us (we shouldn't be RPM suspended when the
773 * interrupt is enabled).
775 if (pm_runtime_suspended(&drv_data->pdev->dev))
776 return IRQ_NONE;
779 * If the device is not yet in RPM suspended state and we get an
780 * interrupt that is meant for another device, check if status bits
781 * are all set to one. That means that the device is already
782 * powered off.
784 status = pxa2xx_spi_read(drv_data, SSSR);
785 if (status == ~0)
786 return IRQ_NONE;
788 sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1);
790 /* Ignore possible writes if we don't need to write */
791 if (!(sccr1_reg & SSCR1_TIE))
792 mask &= ~SSSR_TFS;
794 /* Ignore RX timeout interrupt if it is disabled */
795 if (!(sccr1_reg & SSCR1_TINTE))
796 mask &= ~SSSR_TINT;
798 if (!(status & mask))
799 return IRQ_NONE;
801 pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg & ~drv_data->int_cr1);
802 pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
804 if (!drv_data->master->cur_msg) {
805 handle_bad_msg(drv_data);
806 /* Never fail */
807 return IRQ_HANDLED;
810 return drv_data->transfer_handler(drv_data);
814 * The Quark SPI has an additional 24 bit register (DDS_CLK_RATE) to multiply
815 * input frequency by fractions of 2^24. It also has a divider by 5.
817 * There are formulas to get baud rate value for given input frequency and
818 * divider parameters, such as DDS_CLK_RATE and SCR:
820 * Fsys = 200MHz
822 * Fssp = Fsys * DDS_CLK_RATE / 2^24 (1)
823 * Baud rate = Fsclk = Fssp / (2 * (SCR + 1)) (2)
825 * DDS_CLK_RATE either 2^n or 2^n / 5.
826 * SCR is in range 0 .. 255
828 * Divisor = 5^i * 2^j * 2 * k
829 * i = [0, 1] i = 1 iff j = 0 or j > 3
830 * j = [0, 23] j = 0 iff i = 1
831 * k = [1, 256]
832 * Special case: j = 0, i = 1: Divisor = 2 / 5
834 * Accordingly to the specification the recommended values for DDS_CLK_RATE
835 * are:
836 * Case 1: 2^n, n = [0, 23]
837 * Case 2: 2^24 * 2 / 5 (0x666666)
838 * Case 3: less than or equal to 2^24 / 5 / 16 (0x33333)
840 * In all cases the lowest possible value is better.
842 * The function calculates parameters for all cases and chooses the one closest
843 * to the asked baud rate.
845 static unsigned int quark_x1000_get_clk_div(int rate, u32 *dds)
847 unsigned long xtal = 200000000;
848 unsigned long fref = xtal / 2; /* mandatory division by 2,
849 see (2) */
850 /* case 3 */
851 unsigned long fref1 = fref / 2; /* case 1 */
852 unsigned long fref2 = fref * 2 / 5; /* case 2 */
853 unsigned long scale;
854 unsigned long q, q1, q2;
855 long r, r1, r2;
856 u32 mul;
858 /* Case 1 */
860 /* Set initial value for DDS_CLK_RATE */
861 mul = (1 << 24) >> 1;
863 /* Calculate initial quot */
864 q1 = DIV_ROUND_UP(fref1, rate);
866 /* Scale q1 if it's too big */
867 if (q1 > 256) {
868 /* Scale q1 to range [1, 512] */
869 scale = fls_long(q1 - 1);
870 if (scale > 9) {
871 q1 >>= scale - 9;
872 mul >>= scale - 9;
875 /* Round the result if we have a remainder */
876 q1 += q1 & 1;
879 /* Decrease DDS_CLK_RATE as much as we can without loss in precision */
880 scale = __ffs(q1);
881 q1 >>= scale;
882 mul >>= scale;
884 /* Get the remainder */
885 r1 = abs(fref1 / (1 << (24 - fls_long(mul))) / q1 - rate);
887 /* Case 2 */
889 q2 = DIV_ROUND_UP(fref2, rate);
890 r2 = abs(fref2 / q2 - rate);
893 * Choose the best between two: less remainder we have the better. We
894 * can't go case 2 if q2 is greater than 256 since SCR register can
895 * hold only values 0 .. 255.
897 if (r2 >= r1 || q2 > 256) {
898 /* case 1 is better */
899 r = r1;
900 q = q1;
901 } else {
902 /* case 2 is better */
903 r = r2;
904 q = q2;
905 mul = (1 << 24) * 2 / 5;
908 /* Check case 3 only if the divisor is big enough */
909 if (fref / rate >= 80) {
910 u64 fssp;
911 u32 m;
913 /* Calculate initial quot */
914 q1 = DIV_ROUND_UP(fref, rate);
915 m = (1 << 24) / q1;
917 /* Get the remainder */
918 fssp = (u64)fref * m;
919 do_div(fssp, 1 << 24);
920 r1 = abs(fssp - rate);
922 /* Choose this one if it suits better */
923 if (r1 < r) {
924 /* case 3 is better */
925 q = 1;
926 mul = m;
930 *dds = mul;
931 return q - 1;
934 static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate)
936 unsigned long ssp_clk = drv_data->master->max_speed_hz;
937 const struct ssp_device *ssp = drv_data->ssp;
939 rate = min_t(int, ssp_clk, rate);
941 if (ssp->type == PXA25x_SSP || ssp->type == CE4100_SSP)
942 return (ssp_clk / (2 * rate) - 1) & 0xff;
943 else
944 return (ssp_clk / rate - 1) & 0xfff;
947 static unsigned int pxa2xx_ssp_get_clk_div(struct driver_data *drv_data,
948 int rate)
950 struct chip_data *chip =
951 spi_get_ctldata(drv_data->master->cur_msg->spi);
952 unsigned int clk_div;
954 switch (drv_data->ssp_type) {
955 case QUARK_X1000_SSP:
956 clk_div = quark_x1000_get_clk_div(rate, &chip->dds_rate);
957 break;
958 default:
959 clk_div = ssp_get_clk_div(drv_data, rate);
960 break;
962 return clk_div << 8;
965 static bool pxa2xx_spi_can_dma(struct spi_master *master,
966 struct spi_device *spi,
967 struct spi_transfer *xfer)
969 struct chip_data *chip = spi_get_ctldata(spi);
971 return chip->enable_dma &&
972 xfer->len <= MAX_DMA_LEN &&
973 xfer->len >= chip->dma_burst_size;
976 static void pump_transfers(unsigned long data)
978 struct driver_data *drv_data = (struct driver_data *)data;
979 struct spi_master *master = drv_data->master;
980 struct spi_message *message = master->cur_msg;
981 struct chip_data *chip = spi_get_ctldata(message->spi);
982 u32 dma_thresh = chip->dma_threshold;
983 u32 dma_burst = chip->dma_burst_size;
984 u32 change_mask = pxa2xx_spi_get_ssrc1_change_mask(drv_data);
985 struct spi_transfer *transfer;
986 struct spi_transfer *previous;
987 u32 clk_div;
988 u8 bits;
989 u32 speed;
990 u32 cr0;
991 u32 cr1;
992 int err;
993 int dma_mapped;
995 /* Get current state information */
996 transfer = drv_data->cur_transfer;
998 /* Handle for abort */
999 if (message->state == ERROR_STATE) {
1000 message->status = -EIO;
1001 giveback(drv_data);
1002 return;
1005 /* Handle end of message */
1006 if (message->state == DONE_STATE) {
1007 message->status = 0;
1008 giveback(drv_data);
1009 return;
1012 /* Delay if requested at end of transfer before CS change */
1013 if (message->state == RUNNING_STATE) {
1014 previous = list_entry(transfer->transfer_list.prev,
1015 struct spi_transfer,
1016 transfer_list);
1017 if (previous->delay_usecs)
1018 udelay(previous->delay_usecs);
1020 /* Drop chip select only if cs_change is requested */
1021 if (previous->cs_change)
1022 cs_deassert(drv_data);
1025 /* Check if we can DMA this transfer */
1026 if (transfer->len > MAX_DMA_LEN && chip->enable_dma) {
1028 /* reject already-mapped transfers; PIO won't always work */
1029 if (message->is_dma_mapped
1030 || transfer->rx_dma || transfer->tx_dma) {
1031 dev_err(&drv_data->pdev->dev,
1032 "pump_transfers: mapped transfer length of "
1033 "%u is greater than %d\n",
1034 transfer->len, MAX_DMA_LEN);
1035 message->status = -EINVAL;
1036 giveback(drv_data);
1037 return;
1040 /* warn ... we force this to PIO mode */
1041 dev_warn_ratelimited(&message->spi->dev,
1042 "pump_transfers: DMA disabled for transfer length %ld "
1043 "greater than %d\n",
1044 (long)drv_data->len, MAX_DMA_LEN);
1047 /* Setup the transfer state based on the type of transfer */
1048 if (pxa2xx_spi_flush(drv_data) == 0) {
1049 dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
1050 message->status = -EIO;
1051 giveback(drv_data);
1052 return;
1054 drv_data->n_bytes = chip->n_bytes;
1055 drv_data->tx = (void *)transfer->tx_buf;
1056 drv_data->tx_end = drv_data->tx + transfer->len;
1057 drv_data->rx = transfer->rx_buf;
1058 drv_data->rx_end = drv_data->rx + transfer->len;
1059 drv_data->len = transfer->len;
1060 drv_data->write = drv_data->tx ? chip->write : null_writer;
1061 drv_data->read = drv_data->rx ? chip->read : null_reader;
1063 /* Change speed and bit per word on a per transfer */
1064 bits = transfer->bits_per_word;
1065 speed = transfer->speed_hz;
1067 clk_div = pxa2xx_ssp_get_clk_div(drv_data, speed);
1069 if (bits <= 8) {
1070 drv_data->n_bytes = 1;
1071 drv_data->read = drv_data->read != null_reader ?
1072 u8_reader : null_reader;
1073 drv_data->write = drv_data->write != null_writer ?
1074 u8_writer : null_writer;
1075 } else if (bits <= 16) {
1076 drv_data->n_bytes = 2;
1077 drv_data->read = drv_data->read != null_reader ?
1078 u16_reader : null_reader;
1079 drv_data->write = drv_data->write != null_writer ?
1080 u16_writer : null_writer;
1081 } else if (bits <= 32) {
1082 drv_data->n_bytes = 4;
1083 drv_data->read = drv_data->read != null_reader ?
1084 u32_reader : null_reader;
1085 drv_data->write = drv_data->write != null_writer ?
1086 u32_writer : null_writer;
1089 * if bits/word is changed in dma mode, then must check the
1090 * thresholds and burst also
1092 if (chip->enable_dma) {
1093 if (pxa2xx_spi_set_dma_burst_and_threshold(chip,
1094 message->spi,
1095 bits, &dma_burst,
1096 &dma_thresh))
1097 dev_warn_ratelimited(&message->spi->dev,
1098 "pump_transfers: DMA burst size reduced to match bits_per_word\n");
1101 message->state = RUNNING_STATE;
1103 dma_mapped = master->can_dma &&
1104 master->can_dma(master, message->spi, transfer) &&
1105 master->cur_msg_mapped;
1106 if (dma_mapped) {
1108 /* Ensure we have the correct interrupt handler */
1109 drv_data->transfer_handler = pxa2xx_spi_dma_transfer;
1111 err = pxa2xx_spi_dma_prepare(drv_data, dma_burst);
1112 if (err) {
1113 message->status = err;
1114 giveback(drv_data);
1115 return;
1118 /* Clear status and start DMA engine */
1119 cr1 = chip->cr1 | dma_thresh | drv_data->dma_cr1;
1120 pxa2xx_spi_write(drv_data, SSSR, drv_data->clear_sr);
1122 pxa2xx_spi_dma_start(drv_data);
1123 } else {
1124 /* Ensure we have the correct interrupt handler */
1125 drv_data->transfer_handler = interrupt_transfer;
1127 /* Clear status */
1128 cr1 = chip->cr1 | chip->threshold | drv_data->int_cr1;
1129 write_SSSR_CS(drv_data, drv_data->clear_sr);
1132 /* NOTE: PXA25x_SSP _could_ use external clocking ... */
1133 cr0 = pxa2xx_configure_sscr0(drv_data, clk_div, bits);
1134 if (!pxa25x_ssp_comp(drv_data))
1135 dev_dbg(&message->spi->dev, "%u Hz actual, %s\n",
1136 master->max_speed_hz
1137 / (1 + ((cr0 & SSCR0_SCR(0xfff)) >> 8)),
1138 dma_mapped ? "DMA" : "PIO");
1139 else
1140 dev_dbg(&message->spi->dev, "%u Hz actual, %s\n",
1141 master->max_speed_hz / 2
1142 / (1 + ((cr0 & SSCR0_SCR(0x0ff)) >> 8)),
1143 dma_mapped ? "DMA" : "PIO");
1145 if (is_lpss_ssp(drv_data)) {
1146 if ((pxa2xx_spi_read(drv_data, SSIRF) & 0xff)
1147 != chip->lpss_rx_threshold)
1148 pxa2xx_spi_write(drv_data, SSIRF,
1149 chip->lpss_rx_threshold);
1150 if ((pxa2xx_spi_read(drv_data, SSITF) & 0xffff)
1151 != chip->lpss_tx_threshold)
1152 pxa2xx_spi_write(drv_data, SSITF,
1153 chip->lpss_tx_threshold);
1156 if (is_quark_x1000_ssp(drv_data) &&
1157 (pxa2xx_spi_read(drv_data, DDS_RATE) != chip->dds_rate))
1158 pxa2xx_spi_write(drv_data, DDS_RATE, chip->dds_rate);
1160 /* see if we need to reload the config registers */
1161 if ((pxa2xx_spi_read(drv_data, SSCR0) != cr0)
1162 || (pxa2xx_spi_read(drv_data, SSCR1) & change_mask)
1163 != (cr1 & change_mask)) {
1164 /* stop the SSP, and update the other bits */
1165 pxa2xx_spi_write(drv_data, SSCR0, cr0 & ~SSCR0_SSE);
1166 if (!pxa25x_ssp_comp(drv_data))
1167 pxa2xx_spi_write(drv_data, SSTO, chip->timeout);
1168 /* first set CR1 without interrupt and service enables */
1169 pxa2xx_spi_write(drv_data, SSCR1, cr1 & change_mask);
1170 /* restart the SSP */
1171 pxa2xx_spi_write(drv_data, SSCR0, cr0);
1173 } else {
1174 if (!pxa25x_ssp_comp(drv_data))
1175 pxa2xx_spi_write(drv_data, SSTO, chip->timeout);
1178 cs_assert(drv_data);
1180 /* after chip select, release the data by enabling service
1181 * requests and interrupts, without changing any mode bits */
1182 pxa2xx_spi_write(drv_data, SSCR1, cr1);
1185 static int pxa2xx_spi_transfer_one_message(struct spi_master *master,
1186 struct spi_message *msg)
1188 struct driver_data *drv_data = spi_master_get_devdata(master);
1190 /* Initial message state*/
1191 msg->state = START_STATE;
1192 drv_data->cur_transfer = list_entry(msg->transfers.next,
1193 struct spi_transfer,
1194 transfer_list);
1196 /* Mark as busy and launch transfers */
1197 tasklet_schedule(&drv_data->pump_transfers);
1198 return 0;
1201 static int pxa2xx_spi_unprepare_transfer(struct spi_master *master)
1203 struct driver_data *drv_data = spi_master_get_devdata(master);
1205 /* Disable the SSP now */
1206 pxa2xx_spi_write(drv_data, SSCR0,
1207 pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
1209 return 0;
1212 static int setup_cs(struct spi_device *spi, struct chip_data *chip,
1213 struct pxa2xx_spi_chip *chip_info)
1215 struct driver_data *drv_data = spi_master_get_devdata(spi->master);
1216 struct gpio_desc *gpiod;
1217 int err = 0;
1219 if (chip == NULL)
1220 return 0;
1222 if (drv_data->cs_gpiods) {
1223 gpiod = drv_data->cs_gpiods[spi->chip_select];
1224 if (gpiod) {
1225 chip->gpiod_cs = gpiod;
1226 chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH;
1227 gpiod_set_value(gpiod, chip->gpio_cs_inverted);
1230 return 0;
1233 if (chip_info == NULL)
1234 return 0;
1236 /* NOTE: setup() can be called multiple times, possibly with
1237 * different chip_info, release previously requested GPIO
1239 if (chip->gpiod_cs) {
1240 gpiod_put(chip->gpiod_cs);
1241 chip->gpiod_cs = NULL;
1244 /* If (*cs_control) is provided, ignore GPIO chip select */
1245 if (chip_info->cs_control) {
1246 chip->cs_control = chip_info->cs_control;
1247 return 0;
1250 if (gpio_is_valid(chip_info->gpio_cs)) {
1251 err = gpio_request(chip_info->gpio_cs, "SPI_CS");
1252 if (err) {
1253 dev_err(&spi->dev, "failed to request chip select GPIO%d\n",
1254 chip_info->gpio_cs);
1255 return err;
1258 gpiod = gpio_to_desc(chip_info->gpio_cs);
1259 chip->gpiod_cs = gpiod;
1260 chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH;
1262 err = gpiod_direction_output(gpiod, !chip->gpio_cs_inverted);
1265 return err;
1268 static int setup(struct spi_device *spi)
1270 struct pxa2xx_spi_chip *chip_info;
1271 struct chip_data *chip;
1272 const struct lpss_config *config;
1273 struct driver_data *drv_data = spi_master_get_devdata(spi->master);
1274 uint tx_thres, tx_hi_thres, rx_thres;
1276 switch (drv_data->ssp_type) {
1277 case QUARK_X1000_SSP:
1278 tx_thres = TX_THRESH_QUARK_X1000_DFLT;
1279 tx_hi_thres = 0;
1280 rx_thres = RX_THRESH_QUARK_X1000_DFLT;
1281 break;
1282 case CE4100_SSP:
1283 tx_thres = TX_THRESH_CE4100_DFLT;
1284 tx_hi_thres = 0;
1285 rx_thres = RX_THRESH_CE4100_DFLT;
1286 break;
1287 case LPSS_LPT_SSP:
1288 case LPSS_BYT_SSP:
1289 case LPSS_BSW_SSP:
1290 case LPSS_SPT_SSP:
1291 case LPSS_BXT_SSP:
1292 case LPSS_CNL_SSP:
1293 config = lpss_get_config(drv_data);
1294 tx_thres = config->tx_threshold_lo;
1295 tx_hi_thres = config->tx_threshold_hi;
1296 rx_thres = config->rx_threshold;
1297 break;
1298 default:
1299 tx_thres = TX_THRESH_DFLT;
1300 tx_hi_thres = 0;
1301 rx_thres = RX_THRESH_DFLT;
1302 break;
1305 /* Only alloc on first setup */
1306 chip = spi_get_ctldata(spi);
1307 if (!chip) {
1308 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1309 if (!chip)
1310 return -ENOMEM;
1312 if (drv_data->ssp_type == CE4100_SSP) {
1313 if (spi->chip_select > 4) {
1314 dev_err(&spi->dev,
1315 "failed setup: cs number must not be > 4.\n");
1316 kfree(chip);
1317 return -EINVAL;
1320 chip->frm = spi->chip_select;
1322 chip->enable_dma = drv_data->master_info->enable_dma;
1323 chip->timeout = TIMOUT_DFLT;
1326 /* protocol drivers may change the chip settings, so...
1327 * if chip_info exists, use it */
1328 chip_info = spi->controller_data;
1330 /* chip_info isn't always needed */
1331 chip->cr1 = 0;
1332 if (chip_info) {
1333 if (chip_info->timeout)
1334 chip->timeout = chip_info->timeout;
1335 if (chip_info->tx_threshold)
1336 tx_thres = chip_info->tx_threshold;
1337 if (chip_info->tx_hi_threshold)
1338 tx_hi_thres = chip_info->tx_hi_threshold;
1339 if (chip_info->rx_threshold)
1340 rx_thres = chip_info->rx_threshold;
1341 chip->dma_threshold = 0;
1342 if (chip_info->enable_loopback)
1343 chip->cr1 = SSCR1_LBM;
1346 chip->lpss_rx_threshold = SSIRF_RxThresh(rx_thres);
1347 chip->lpss_tx_threshold = SSITF_TxLoThresh(tx_thres)
1348 | SSITF_TxHiThresh(tx_hi_thres);
1350 /* set dma burst and threshold outside of chip_info path so that if
1351 * chip_info goes away after setting chip->enable_dma, the
1352 * burst and threshold can still respond to changes in bits_per_word */
1353 if (chip->enable_dma) {
1354 /* set up legal burst and threshold for dma */
1355 if (pxa2xx_spi_set_dma_burst_and_threshold(chip, spi,
1356 spi->bits_per_word,
1357 &chip->dma_burst_size,
1358 &chip->dma_threshold)) {
1359 dev_warn(&spi->dev,
1360 "in setup: DMA burst size reduced to match bits_per_word\n");
1364 switch (drv_data->ssp_type) {
1365 case QUARK_X1000_SSP:
1366 chip->threshold = (QUARK_X1000_SSCR1_RxTresh(rx_thres)
1367 & QUARK_X1000_SSCR1_RFT)
1368 | (QUARK_X1000_SSCR1_TxTresh(tx_thres)
1369 & QUARK_X1000_SSCR1_TFT);
1370 break;
1371 case CE4100_SSP:
1372 chip->threshold = (CE4100_SSCR1_RxTresh(rx_thres) & CE4100_SSCR1_RFT) |
1373 (CE4100_SSCR1_TxTresh(tx_thres) & CE4100_SSCR1_TFT);
1374 break;
1375 default:
1376 chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) |
1377 (SSCR1_TxTresh(tx_thres) & SSCR1_TFT);
1378 break;
1381 chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH);
1382 chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0)
1383 | (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0);
1385 if (spi->mode & SPI_LOOP)
1386 chip->cr1 |= SSCR1_LBM;
1388 if (spi->bits_per_word <= 8) {
1389 chip->n_bytes = 1;
1390 chip->read = u8_reader;
1391 chip->write = u8_writer;
1392 } else if (spi->bits_per_word <= 16) {
1393 chip->n_bytes = 2;
1394 chip->read = u16_reader;
1395 chip->write = u16_writer;
1396 } else if (spi->bits_per_word <= 32) {
1397 chip->n_bytes = 4;
1398 chip->read = u32_reader;
1399 chip->write = u32_writer;
1402 spi_set_ctldata(spi, chip);
1404 if (drv_data->ssp_type == CE4100_SSP)
1405 return 0;
1407 return setup_cs(spi, chip, chip_info);
1410 static void cleanup(struct spi_device *spi)
1412 struct chip_data *chip = spi_get_ctldata(spi);
1413 struct driver_data *drv_data = spi_master_get_devdata(spi->master);
1415 if (!chip)
1416 return;
1418 if (drv_data->ssp_type != CE4100_SSP && !drv_data->cs_gpiods &&
1419 chip->gpiod_cs)
1420 gpiod_put(chip->gpiod_cs);
1422 kfree(chip);
1425 #ifdef CONFIG_PCI
1426 #ifdef CONFIG_ACPI
1428 static const struct acpi_device_id pxa2xx_spi_acpi_match[] = {
1429 { "INT33C0", LPSS_LPT_SSP },
1430 { "INT33C1", LPSS_LPT_SSP },
1431 { "INT3430", LPSS_LPT_SSP },
1432 { "INT3431", LPSS_LPT_SSP },
1433 { "80860F0E", LPSS_BYT_SSP },
1434 { "8086228E", LPSS_BSW_SSP },
1435 { },
1437 MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match);
1439 static int pxa2xx_spi_get_port_id(struct acpi_device *adev)
1441 unsigned int devid;
1442 int port_id = -1;
1444 if (adev && adev->pnp.unique_id &&
1445 !kstrtouint(adev->pnp.unique_id, 0, &devid))
1446 port_id = devid;
1447 return port_id;
1449 #else /* !CONFIG_ACPI */
1450 static int pxa2xx_spi_get_port_id(struct acpi_device *adev)
1452 return -1;
1454 #endif
1457 * PCI IDs of compound devices that integrate both host controller and private
1458 * integrated DMA engine. Please note these are not used in module
1459 * autoloading and probing in this module but matching the LPSS SSP type.
1461 static const struct pci_device_id pxa2xx_spi_pci_compound_match[] = {
1462 /* SPT-LP */
1463 { PCI_VDEVICE(INTEL, 0x9d29), LPSS_SPT_SSP },
1464 { PCI_VDEVICE(INTEL, 0x9d2a), LPSS_SPT_SSP },
1465 /* SPT-H */
1466 { PCI_VDEVICE(INTEL, 0xa129), LPSS_SPT_SSP },
1467 { PCI_VDEVICE(INTEL, 0xa12a), LPSS_SPT_SSP },
1468 /* KBL-H */
1469 { PCI_VDEVICE(INTEL, 0xa2a9), LPSS_SPT_SSP },
1470 { PCI_VDEVICE(INTEL, 0xa2aa), LPSS_SPT_SSP },
1471 /* BXT A-Step */
1472 { PCI_VDEVICE(INTEL, 0x0ac2), LPSS_BXT_SSP },
1473 { PCI_VDEVICE(INTEL, 0x0ac4), LPSS_BXT_SSP },
1474 { PCI_VDEVICE(INTEL, 0x0ac6), LPSS_BXT_SSP },
1475 /* BXT B-Step */
1476 { PCI_VDEVICE(INTEL, 0x1ac2), LPSS_BXT_SSP },
1477 { PCI_VDEVICE(INTEL, 0x1ac4), LPSS_BXT_SSP },
1478 { PCI_VDEVICE(INTEL, 0x1ac6), LPSS_BXT_SSP },
1479 /* GLK */
1480 { PCI_VDEVICE(INTEL, 0x31c2), LPSS_BXT_SSP },
1481 { PCI_VDEVICE(INTEL, 0x31c4), LPSS_BXT_SSP },
1482 { PCI_VDEVICE(INTEL, 0x31c6), LPSS_BXT_SSP },
1483 /* APL */
1484 { PCI_VDEVICE(INTEL, 0x5ac2), LPSS_BXT_SSP },
1485 { PCI_VDEVICE(INTEL, 0x5ac4), LPSS_BXT_SSP },
1486 { PCI_VDEVICE(INTEL, 0x5ac6), LPSS_BXT_SSP },
1487 /* CNL-LP */
1488 { PCI_VDEVICE(INTEL, 0x9daa), LPSS_CNL_SSP },
1489 { PCI_VDEVICE(INTEL, 0x9dab), LPSS_CNL_SSP },
1490 { PCI_VDEVICE(INTEL, 0x9dfb), LPSS_CNL_SSP },
1491 /* CNL-H */
1492 { PCI_VDEVICE(INTEL, 0xa32a), LPSS_CNL_SSP },
1493 { PCI_VDEVICE(INTEL, 0xa32b), LPSS_CNL_SSP },
1494 { PCI_VDEVICE(INTEL, 0xa37b), LPSS_CNL_SSP },
1495 { },
1498 static bool pxa2xx_spi_idma_filter(struct dma_chan *chan, void *param)
1500 struct device *dev = param;
1502 if (dev != chan->device->dev->parent)
1503 return false;
1505 return true;
1508 static struct pxa2xx_spi_master *
1509 pxa2xx_spi_init_pdata(struct platform_device *pdev)
1511 struct pxa2xx_spi_master *pdata;
1512 struct acpi_device *adev;
1513 struct ssp_device *ssp;
1514 struct resource *res;
1515 const struct acpi_device_id *adev_id = NULL;
1516 const struct pci_device_id *pcidev_id = NULL;
1517 int type;
1519 adev = ACPI_COMPANION(&pdev->dev);
1521 if (dev_is_pci(pdev->dev.parent))
1522 pcidev_id = pci_match_id(pxa2xx_spi_pci_compound_match,
1523 to_pci_dev(pdev->dev.parent));
1524 else if (adev)
1525 adev_id = acpi_match_device(pdev->dev.driver->acpi_match_table,
1526 &pdev->dev);
1527 else
1528 return NULL;
1530 if (adev_id)
1531 type = (int)adev_id->driver_data;
1532 else if (pcidev_id)
1533 type = (int)pcidev_id->driver_data;
1534 else
1535 return NULL;
1537 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
1538 if (!pdata)
1539 return NULL;
1541 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1542 if (!res)
1543 return NULL;
1545 ssp = &pdata->ssp;
1547 ssp->phys_base = res->start;
1548 ssp->mmio_base = devm_ioremap_resource(&pdev->dev, res);
1549 if (IS_ERR(ssp->mmio_base))
1550 return NULL;
1552 if (pcidev_id) {
1553 pdata->tx_param = pdev->dev.parent;
1554 pdata->rx_param = pdev->dev.parent;
1555 pdata->dma_filter = pxa2xx_spi_idma_filter;
1558 ssp->clk = devm_clk_get(&pdev->dev, NULL);
1559 ssp->irq = platform_get_irq(pdev, 0);
1560 ssp->type = type;
1561 ssp->pdev = pdev;
1562 ssp->port_id = pxa2xx_spi_get_port_id(adev);
1564 pdata->num_chipselect = 1;
1565 pdata->enable_dma = true;
1567 return pdata;
1570 #else /* !CONFIG_PCI */
1571 static inline struct pxa2xx_spi_master *
1572 pxa2xx_spi_init_pdata(struct platform_device *pdev)
1574 return NULL;
1576 #endif
1578 static int pxa2xx_spi_fw_translate_cs(struct spi_master *master, unsigned cs)
1580 struct driver_data *drv_data = spi_master_get_devdata(master);
1582 if (has_acpi_companion(&drv_data->pdev->dev)) {
1583 switch (drv_data->ssp_type) {
1585 * For Atoms the ACPI DeviceSelection used by the Windows
1586 * driver starts from 1 instead of 0 so translate it here
1587 * to match what Linux expects.
1589 case LPSS_BYT_SSP:
1590 case LPSS_BSW_SSP:
1591 return cs - 1;
1593 default:
1594 break;
1598 return cs;
1601 static int pxa2xx_spi_probe(struct platform_device *pdev)
1603 struct device *dev = &pdev->dev;
1604 struct pxa2xx_spi_master *platform_info;
1605 struct spi_master *master;
1606 struct driver_data *drv_data;
1607 struct ssp_device *ssp;
1608 const struct lpss_config *config;
1609 int status, count;
1610 u32 tmp;
1612 platform_info = dev_get_platdata(dev);
1613 if (!platform_info) {
1614 platform_info = pxa2xx_spi_init_pdata(pdev);
1615 if (!platform_info) {
1616 dev_err(&pdev->dev, "missing platform data\n");
1617 return -ENODEV;
1621 ssp = pxa_ssp_request(pdev->id, pdev->name);
1622 if (!ssp)
1623 ssp = &platform_info->ssp;
1625 if (!ssp->mmio_base) {
1626 dev_err(&pdev->dev, "failed to get ssp\n");
1627 return -ENODEV;
1630 master = spi_alloc_master(dev, sizeof(struct driver_data));
1631 if (!master) {
1632 dev_err(&pdev->dev, "cannot alloc spi_master\n");
1633 pxa_ssp_free(ssp);
1634 return -ENOMEM;
1636 drv_data = spi_master_get_devdata(master);
1637 drv_data->master = master;
1638 drv_data->master_info = platform_info;
1639 drv_data->pdev = pdev;
1640 drv_data->ssp = ssp;
1642 master->dev.of_node = pdev->dev.of_node;
1643 /* the spi->mode bits understood by this driver: */
1644 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
1646 master->bus_num = ssp->port_id;
1647 master->dma_alignment = DMA_ALIGNMENT;
1648 master->cleanup = cleanup;
1649 master->setup = setup;
1650 master->transfer_one_message = pxa2xx_spi_transfer_one_message;
1651 master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer;
1652 master->fw_translate_cs = pxa2xx_spi_fw_translate_cs;
1653 master->auto_runtime_pm = true;
1654 master->flags = SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX;
1656 drv_data->ssp_type = ssp->type;
1658 drv_data->ioaddr = ssp->mmio_base;
1659 drv_data->ssdr_physical = ssp->phys_base + SSDR;
1660 if (pxa25x_ssp_comp(drv_data)) {
1661 switch (drv_data->ssp_type) {
1662 case QUARK_X1000_SSP:
1663 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1664 break;
1665 default:
1666 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
1667 break;
1670 drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE;
1671 drv_data->dma_cr1 = 0;
1672 drv_data->clear_sr = SSSR_ROR;
1673 drv_data->mask_sr = SSSR_RFS | SSSR_TFS | SSSR_ROR;
1674 } else {
1675 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1676 drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE | SSCR1_TINTE;
1677 drv_data->dma_cr1 = DEFAULT_DMA_CR1;
1678 drv_data->clear_sr = SSSR_ROR | SSSR_TINT;
1679 drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS | SSSR_ROR;
1682 status = request_irq(ssp->irq, ssp_int, IRQF_SHARED, dev_name(dev),
1683 drv_data);
1684 if (status < 0) {
1685 dev_err(&pdev->dev, "cannot get IRQ %d\n", ssp->irq);
1686 goto out_error_master_alloc;
1689 /* Setup DMA if requested */
1690 if (platform_info->enable_dma) {
1691 status = pxa2xx_spi_dma_setup(drv_data);
1692 if (status) {
1693 dev_dbg(dev, "no DMA channels available, using PIO\n");
1694 platform_info->enable_dma = false;
1695 } else {
1696 master->can_dma = pxa2xx_spi_can_dma;
1700 /* Enable SOC clock */
1701 clk_prepare_enable(ssp->clk);
1703 master->max_speed_hz = clk_get_rate(ssp->clk);
1705 /* Load default SSP configuration */
1706 pxa2xx_spi_write(drv_data, SSCR0, 0);
1707 switch (drv_data->ssp_type) {
1708 case QUARK_X1000_SSP:
1709 tmp = QUARK_X1000_SSCR1_RxTresh(RX_THRESH_QUARK_X1000_DFLT) |
1710 QUARK_X1000_SSCR1_TxTresh(TX_THRESH_QUARK_X1000_DFLT);
1711 pxa2xx_spi_write(drv_data, SSCR1, tmp);
1713 /* using the Motorola SPI protocol and use 8 bit frame */
1714 tmp = QUARK_X1000_SSCR0_Motorola | QUARK_X1000_SSCR0_DataSize(8);
1715 pxa2xx_spi_write(drv_data, SSCR0, tmp);
1716 break;
1717 case CE4100_SSP:
1718 tmp = CE4100_SSCR1_RxTresh(RX_THRESH_CE4100_DFLT) |
1719 CE4100_SSCR1_TxTresh(TX_THRESH_CE4100_DFLT);
1720 pxa2xx_spi_write(drv_data, SSCR1, tmp);
1721 tmp = SSCR0_SCR(2) | SSCR0_Motorola | SSCR0_DataSize(8);
1722 pxa2xx_spi_write(drv_data, SSCR0, tmp);
1723 break;
1724 default:
1725 tmp = SSCR1_RxTresh(RX_THRESH_DFLT) |
1726 SSCR1_TxTresh(TX_THRESH_DFLT);
1727 pxa2xx_spi_write(drv_data, SSCR1, tmp);
1728 tmp = SSCR0_SCR(2) | SSCR0_Motorola | SSCR0_DataSize(8);
1729 pxa2xx_spi_write(drv_data, SSCR0, tmp);
1730 break;
1733 if (!pxa25x_ssp_comp(drv_data))
1734 pxa2xx_spi_write(drv_data, SSTO, 0);
1736 if (!is_quark_x1000_ssp(drv_data))
1737 pxa2xx_spi_write(drv_data, SSPSP, 0);
1739 if (is_lpss_ssp(drv_data)) {
1740 lpss_ssp_setup(drv_data);
1741 config = lpss_get_config(drv_data);
1742 if (config->reg_capabilities >= 0) {
1743 tmp = __lpss_ssp_read_priv(drv_data,
1744 config->reg_capabilities);
1745 tmp &= LPSS_CAPS_CS_EN_MASK;
1746 tmp >>= LPSS_CAPS_CS_EN_SHIFT;
1747 platform_info->num_chipselect = ffz(tmp);
1748 } else if (config->cs_num) {
1749 platform_info->num_chipselect = config->cs_num;
1752 master->num_chipselect = platform_info->num_chipselect;
1754 count = gpiod_count(&pdev->dev, "cs");
1755 if (count > 0) {
1756 int i;
1758 master->num_chipselect = max_t(int, count,
1759 master->num_chipselect);
1761 drv_data->cs_gpiods = devm_kcalloc(&pdev->dev,
1762 master->num_chipselect, sizeof(struct gpio_desc *),
1763 GFP_KERNEL);
1764 if (!drv_data->cs_gpiods) {
1765 status = -ENOMEM;
1766 goto out_error_clock_enabled;
1769 for (i = 0; i < master->num_chipselect; i++) {
1770 struct gpio_desc *gpiod;
1772 gpiod = devm_gpiod_get_index(dev, "cs", i, GPIOD_ASIS);
1773 if (IS_ERR(gpiod)) {
1774 /* Means use native chip select */
1775 if (PTR_ERR(gpiod) == -ENOENT)
1776 continue;
1778 status = (int)PTR_ERR(gpiod);
1779 goto out_error_clock_enabled;
1780 } else {
1781 drv_data->cs_gpiods[i] = gpiod;
1786 tasklet_init(&drv_data->pump_transfers, pump_transfers,
1787 (unsigned long)drv_data);
1789 pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
1790 pm_runtime_use_autosuspend(&pdev->dev);
1791 pm_runtime_set_active(&pdev->dev);
1792 pm_runtime_enable(&pdev->dev);
1794 /* Register with the SPI framework */
1795 platform_set_drvdata(pdev, drv_data);
1796 status = devm_spi_register_master(&pdev->dev, master);
1797 if (status != 0) {
1798 dev_err(&pdev->dev, "problem registering spi master\n");
1799 goto out_error_clock_enabled;
1802 return status;
1804 out_error_clock_enabled:
1805 clk_disable_unprepare(ssp->clk);
1806 pxa2xx_spi_dma_release(drv_data);
1807 free_irq(ssp->irq, drv_data);
1809 out_error_master_alloc:
1810 spi_master_put(master);
1811 pxa_ssp_free(ssp);
1812 return status;
1815 static int pxa2xx_spi_remove(struct platform_device *pdev)
1817 struct driver_data *drv_data = platform_get_drvdata(pdev);
1818 struct ssp_device *ssp;
1820 if (!drv_data)
1821 return 0;
1822 ssp = drv_data->ssp;
1824 pm_runtime_get_sync(&pdev->dev);
1826 /* Disable the SSP at the peripheral and SOC level */
1827 pxa2xx_spi_write(drv_data, SSCR0, 0);
1828 clk_disable_unprepare(ssp->clk);
1830 /* Release DMA */
1831 if (drv_data->master_info->enable_dma)
1832 pxa2xx_spi_dma_release(drv_data);
1834 pm_runtime_put_noidle(&pdev->dev);
1835 pm_runtime_disable(&pdev->dev);
1837 /* Release IRQ */
1838 free_irq(ssp->irq, drv_data);
1840 /* Release SSP */
1841 pxa_ssp_free(ssp);
1843 return 0;
1846 static void pxa2xx_spi_shutdown(struct platform_device *pdev)
1848 int status = 0;
1850 if ((status = pxa2xx_spi_remove(pdev)) != 0)
1851 dev_err(&pdev->dev, "shutdown failed with %d\n", status);
1854 #ifdef CONFIG_PM_SLEEP
1855 static int pxa2xx_spi_suspend(struct device *dev)
1857 struct driver_data *drv_data = dev_get_drvdata(dev);
1858 struct ssp_device *ssp = drv_data->ssp;
1859 int status;
1861 status = spi_master_suspend(drv_data->master);
1862 if (status != 0)
1863 return status;
1864 pxa2xx_spi_write(drv_data, SSCR0, 0);
1866 if (!pm_runtime_suspended(dev))
1867 clk_disable_unprepare(ssp->clk);
1869 return 0;
1872 static int pxa2xx_spi_resume(struct device *dev)
1874 struct driver_data *drv_data = dev_get_drvdata(dev);
1875 struct ssp_device *ssp = drv_data->ssp;
1876 int status;
1878 /* Enable the SSP clock */
1879 if (!pm_runtime_suspended(dev))
1880 clk_prepare_enable(ssp->clk);
1882 /* Restore LPSS private register bits */
1883 if (is_lpss_ssp(drv_data))
1884 lpss_ssp_setup(drv_data);
1886 /* Start the queue running */
1887 status = spi_master_resume(drv_data->master);
1888 if (status != 0) {
1889 dev_err(dev, "problem starting queue (%d)\n", status);
1890 return status;
1893 return 0;
1895 #endif
1897 #ifdef CONFIG_PM
1898 static int pxa2xx_spi_runtime_suspend(struct device *dev)
1900 struct driver_data *drv_data = dev_get_drvdata(dev);
1902 clk_disable_unprepare(drv_data->ssp->clk);
1903 return 0;
1906 static int pxa2xx_spi_runtime_resume(struct device *dev)
1908 struct driver_data *drv_data = dev_get_drvdata(dev);
1910 clk_prepare_enable(drv_data->ssp->clk);
1911 return 0;
1913 #endif
1915 static const struct dev_pm_ops pxa2xx_spi_pm_ops = {
1916 SET_SYSTEM_SLEEP_PM_OPS(pxa2xx_spi_suspend, pxa2xx_spi_resume)
1917 SET_RUNTIME_PM_OPS(pxa2xx_spi_runtime_suspend,
1918 pxa2xx_spi_runtime_resume, NULL)
1921 static struct platform_driver driver = {
1922 .driver = {
1923 .name = "pxa2xx-spi",
1924 .pm = &pxa2xx_spi_pm_ops,
1925 .acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match),
1927 .probe = pxa2xx_spi_probe,
1928 .remove = pxa2xx_spi_remove,
1929 .shutdown = pxa2xx_spi_shutdown,
1932 static int __init pxa2xx_spi_init(void)
1934 return platform_driver_register(&driver);
1936 subsys_initcall(pxa2xx_spi_init);
1938 static void __exit pxa2xx_spi_exit(void)
1940 platform_driver_unregister(&driver);
1942 module_exit(pxa2xx_spi_exit);