x86/mm/pat: Don't report PAT on CPUs that don't support it
[linux/fpc-iii.git] / drivers / spi / spi-pxa2xx.c
blob47b65d7c40721eaf39fc0ba0e9dfa016a5407cfa
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,
156 static inline const struct lpss_config
157 *lpss_get_config(const struct driver_data *drv_data)
159 return &lpss_platforms[drv_data->ssp_type - LPSS_LPT_SSP];
162 static bool is_lpss_ssp(const struct driver_data *drv_data)
164 switch (drv_data->ssp_type) {
165 case LPSS_LPT_SSP:
166 case LPSS_BYT_SSP:
167 case LPSS_BSW_SSP:
168 case LPSS_SPT_SSP:
169 case LPSS_BXT_SSP:
170 return true;
171 default:
172 return false;
176 static bool is_quark_x1000_ssp(const struct driver_data *drv_data)
178 return drv_data->ssp_type == QUARK_X1000_SSP;
181 static u32 pxa2xx_spi_get_ssrc1_change_mask(const struct driver_data *drv_data)
183 switch (drv_data->ssp_type) {
184 case QUARK_X1000_SSP:
185 return QUARK_X1000_SSCR1_CHANGE_MASK;
186 case CE4100_SSP:
187 return CE4100_SSCR1_CHANGE_MASK;
188 default:
189 return SSCR1_CHANGE_MASK;
193 static u32
194 pxa2xx_spi_get_rx_default_thre(const struct driver_data *drv_data)
196 switch (drv_data->ssp_type) {
197 case QUARK_X1000_SSP:
198 return RX_THRESH_QUARK_X1000_DFLT;
199 case CE4100_SSP:
200 return RX_THRESH_CE4100_DFLT;
201 default:
202 return RX_THRESH_DFLT;
206 static bool pxa2xx_spi_txfifo_full(const struct driver_data *drv_data)
208 u32 mask;
210 switch (drv_data->ssp_type) {
211 case QUARK_X1000_SSP:
212 mask = QUARK_X1000_SSSR_TFL_MASK;
213 break;
214 case CE4100_SSP:
215 mask = CE4100_SSSR_TFL_MASK;
216 break;
217 default:
218 mask = SSSR_TFL_MASK;
219 break;
222 return (pxa2xx_spi_read(drv_data, SSSR) & mask) == mask;
225 static void pxa2xx_spi_clear_rx_thre(const struct driver_data *drv_data,
226 u32 *sccr1_reg)
228 u32 mask;
230 switch (drv_data->ssp_type) {
231 case QUARK_X1000_SSP:
232 mask = QUARK_X1000_SSCR1_RFT;
233 break;
234 case CE4100_SSP:
235 mask = CE4100_SSCR1_RFT;
236 break;
237 default:
238 mask = SSCR1_RFT;
239 break;
241 *sccr1_reg &= ~mask;
244 static void pxa2xx_spi_set_rx_thre(const struct driver_data *drv_data,
245 u32 *sccr1_reg, u32 threshold)
247 switch (drv_data->ssp_type) {
248 case QUARK_X1000_SSP:
249 *sccr1_reg |= QUARK_X1000_SSCR1_RxTresh(threshold);
250 break;
251 case CE4100_SSP:
252 *sccr1_reg |= CE4100_SSCR1_RxTresh(threshold);
253 break;
254 default:
255 *sccr1_reg |= SSCR1_RxTresh(threshold);
256 break;
260 static u32 pxa2xx_configure_sscr0(const struct driver_data *drv_data,
261 u32 clk_div, u8 bits)
263 switch (drv_data->ssp_type) {
264 case QUARK_X1000_SSP:
265 return clk_div
266 | QUARK_X1000_SSCR0_Motorola
267 | QUARK_X1000_SSCR0_DataSize(bits > 32 ? 8 : bits)
268 | SSCR0_SSE;
269 default:
270 return clk_div
271 | SSCR0_Motorola
272 | SSCR0_DataSize(bits > 16 ? bits - 16 : bits)
273 | SSCR0_SSE
274 | (bits > 16 ? SSCR0_EDSS : 0);
279 * Read and write LPSS SSP private registers. Caller must first check that
280 * is_lpss_ssp() returns true before these can be called.
282 static u32 __lpss_ssp_read_priv(struct driver_data *drv_data, unsigned offset)
284 WARN_ON(!drv_data->lpss_base);
285 return readl(drv_data->lpss_base + offset);
288 static void __lpss_ssp_write_priv(struct driver_data *drv_data,
289 unsigned offset, u32 value)
291 WARN_ON(!drv_data->lpss_base);
292 writel(value, drv_data->lpss_base + offset);
296 * lpss_ssp_setup - perform LPSS SSP specific setup
297 * @drv_data: pointer to the driver private data
299 * Perform LPSS SSP specific setup. This function must be called first if
300 * one is going to use LPSS SSP private registers.
302 static void lpss_ssp_setup(struct driver_data *drv_data)
304 const struct lpss_config *config;
305 u32 value;
307 config = lpss_get_config(drv_data);
308 drv_data->lpss_base = drv_data->ioaddr + config->offset;
310 /* Enable software chip select control */
311 value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
312 value &= ~(LPSS_CS_CONTROL_SW_MODE | LPSS_CS_CONTROL_CS_HIGH);
313 value |= LPSS_CS_CONTROL_SW_MODE | LPSS_CS_CONTROL_CS_HIGH;
314 __lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
316 /* Enable multiblock DMA transfers */
317 if (drv_data->master_info->enable_dma) {
318 __lpss_ssp_write_priv(drv_data, config->reg_ssp, 1);
320 if (config->reg_general >= 0) {
321 value = __lpss_ssp_read_priv(drv_data,
322 config->reg_general);
323 value |= LPSS_GENERAL_REG_RXTO_HOLDOFF_DISABLE;
324 __lpss_ssp_write_priv(drv_data,
325 config->reg_general, value);
330 static void lpss_ssp_select_cs(struct driver_data *drv_data,
331 const struct lpss_config *config)
333 u32 value, cs;
335 if (!config->cs_sel_mask)
336 return;
338 value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
340 cs = drv_data->master->cur_msg->spi->chip_select;
341 cs <<= config->cs_sel_shift;
342 if (cs != (value & config->cs_sel_mask)) {
344 * When switching another chip select output active the
345 * output must be selected first and wait 2 ssp_clk cycles
346 * before changing state to active. Otherwise a short
347 * glitch will occur on the previous chip select since
348 * output select is latched but state control is not.
350 value &= ~config->cs_sel_mask;
351 value |= cs;
352 __lpss_ssp_write_priv(drv_data,
353 config->reg_cs_ctrl, value);
354 ndelay(1000000000 /
355 (drv_data->master->max_speed_hz / 2));
359 static void lpss_ssp_cs_control(struct driver_data *drv_data, bool enable)
361 const struct lpss_config *config;
362 u32 value;
364 config = lpss_get_config(drv_data);
366 if (enable)
367 lpss_ssp_select_cs(drv_data, config);
369 value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
370 if (enable)
371 value &= ~LPSS_CS_CONTROL_CS_HIGH;
372 else
373 value |= LPSS_CS_CONTROL_CS_HIGH;
374 __lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
377 static void cs_assert(struct driver_data *drv_data)
379 struct chip_data *chip =
380 spi_get_ctldata(drv_data->master->cur_msg->spi);
382 if (drv_data->ssp_type == CE4100_SSP) {
383 pxa2xx_spi_write(drv_data, SSSR, chip->frm);
384 return;
387 if (chip->cs_control) {
388 chip->cs_control(PXA2XX_CS_ASSERT);
389 return;
392 if (gpio_is_valid(chip->gpio_cs)) {
393 gpio_set_value(chip->gpio_cs, chip->gpio_cs_inverted);
394 return;
397 if (is_lpss_ssp(drv_data))
398 lpss_ssp_cs_control(drv_data, true);
401 static void cs_deassert(struct driver_data *drv_data)
403 struct chip_data *chip =
404 spi_get_ctldata(drv_data->master->cur_msg->spi);
406 if (drv_data->ssp_type == CE4100_SSP)
407 return;
409 if (chip->cs_control) {
410 chip->cs_control(PXA2XX_CS_DEASSERT);
411 return;
414 if (gpio_is_valid(chip->gpio_cs)) {
415 gpio_set_value(chip->gpio_cs, !chip->gpio_cs_inverted);
416 return;
419 if (is_lpss_ssp(drv_data))
420 lpss_ssp_cs_control(drv_data, false);
423 int pxa2xx_spi_flush(struct driver_data *drv_data)
425 unsigned long limit = loops_per_jiffy << 1;
427 do {
428 while (pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
429 pxa2xx_spi_read(drv_data, SSDR);
430 } while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY) && --limit);
431 write_SSSR_CS(drv_data, SSSR_ROR);
433 return limit;
436 static int null_writer(struct driver_data *drv_data)
438 u8 n_bytes = drv_data->n_bytes;
440 if (pxa2xx_spi_txfifo_full(drv_data)
441 || (drv_data->tx == drv_data->tx_end))
442 return 0;
444 pxa2xx_spi_write(drv_data, SSDR, 0);
445 drv_data->tx += n_bytes;
447 return 1;
450 static int null_reader(struct driver_data *drv_data)
452 u8 n_bytes = drv_data->n_bytes;
454 while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
455 && (drv_data->rx < drv_data->rx_end)) {
456 pxa2xx_spi_read(drv_data, SSDR);
457 drv_data->rx += n_bytes;
460 return drv_data->rx == drv_data->rx_end;
463 static int u8_writer(struct driver_data *drv_data)
465 if (pxa2xx_spi_txfifo_full(drv_data)
466 || (drv_data->tx == drv_data->tx_end))
467 return 0;
469 pxa2xx_spi_write(drv_data, SSDR, *(u8 *)(drv_data->tx));
470 ++drv_data->tx;
472 return 1;
475 static int u8_reader(struct driver_data *drv_data)
477 while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
478 && (drv_data->rx < drv_data->rx_end)) {
479 *(u8 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
480 ++drv_data->rx;
483 return drv_data->rx == drv_data->rx_end;
486 static int u16_writer(struct driver_data *drv_data)
488 if (pxa2xx_spi_txfifo_full(drv_data)
489 || (drv_data->tx == drv_data->tx_end))
490 return 0;
492 pxa2xx_spi_write(drv_data, SSDR, *(u16 *)(drv_data->tx));
493 drv_data->tx += 2;
495 return 1;
498 static int u16_reader(struct driver_data *drv_data)
500 while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
501 && (drv_data->rx < drv_data->rx_end)) {
502 *(u16 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
503 drv_data->rx += 2;
506 return drv_data->rx == drv_data->rx_end;
509 static int u32_writer(struct driver_data *drv_data)
511 if (pxa2xx_spi_txfifo_full(drv_data)
512 || (drv_data->tx == drv_data->tx_end))
513 return 0;
515 pxa2xx_spi_write(drv_data, SSDR, *(u32 *)(drv_data->tx));
516 drv_data->tx += 4;
518 return 1;
521 static int u32_reader(struct driver_data *drv_data)
523 while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
524 && (drv_data->rx < drv_data->rx_end)) {
525 *(u32 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
526 drv_data->rx += 4;
529 return drv_data->rx == drv_data->rx_end;
532 void *pxa2xx_spi_next_transfer(struct driver_data *drv_data)
534 struct spi_message *msg = drv_data->master->cur_msg;
535 struct spi_transfer *trans = drv_data->cur_transfer;
537 /* Move to next transfer */
538 if (trans->transfer_list.next != &msg->transfers) {
539 drv_data->cur_transfer =
540 list_entry(trans->transfer_list.next,
541 struct spi_transfer,
542 transfer_list);
543 return RUNNING_STATE;
544 } else
545 return DONE_STATE;
548 /* caller already set message->status; dma and pio irqs are blocked */
549 static void giveback(struct driver_data *drv_data)
551 struct spi_transfer* last_transfer;
552 struct spi_message *msg;
553 unsigned long timeout;
555 msg = drv_data->master->cur_msg;
556 drv_data->cur_transfer = NULL;
558 last_transfer = list_last_entry(&msg->transfers, struct spi_transfer,
559 transfer_list);
561 /* Delay if requested before any change in chip select */
562 if (last_transfer->delay_usecs)
563 udelay(last_transfer->delay_usecs);
565 /* Wait until SSP becomes idle before deasserting the CS */
566 timeout = jiffies + msecs_to_jiffies(10);
567 while (pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY &&
568 !time_after(jiffies, timeout))
569 cpu_relax();
571 /* Drop chip select UNLESS cs_change is true or we are returning
572 * a message with an error, or next message is for another chip
574 if (!last_transfer->cs_change)
575 cs_deassert(drv_data);
576 else {
577 struct spi_message *next_msg;
579 /* Holding of cs was hinted, but we need to make sure
580 * the next message is for the same chip. Don't waste
581 * time with the following tests unless this was hinted.
583 * We cannot postpone this until pump_messages, because
584 * after calling msg->complete (below) the driver that
585 * sent the current message could be unloaded, which
586 * could invalidate the cs_control() callback...
589 /* get a pointer to the next message, if any */
590 next_msg = spi_get_next_queued_message(drv_data->master);
592 /* see if the next and current messages point
593 * to the same chip
595 if ((next_msg && next_msg->spi != msg->spi) ||
596 msg->state == ERROR_STATE)
597 cs_deassert(drv_data);
600 spi_finalize_current_message(drv_data->master);
603 static void reset_sccr1(struct driver_data *drv_data)
605 struct chip_data *chip =
606 spi_get_ctldata(drv_data->master->cur_msg->spi);
607 u32 sccr1_reg;
609 sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1) & ~drv_data->int_cr1;
610 switch (drv_data->ssp_type) {
611 case QUARK_X1000_SSP:
612 sccr1_reg &= ~QUARK_X1000_SSCR1_RFT;
613 break;
614 case CE4100_SSP:
615 sccr1_reg &= ~CE4100_SSCR1_RFT;
616 break;
617 default:
618 sccr1_reg &= ~SSCR1_RFT;
619 break;
621 sccr1_reg |= chip->threshold;
622 pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
625 static void int_error_stop(struct driver_data *drv_data, const char* msg)
627 /* Stop and reset SSP */
628 write_SSSR_CS(drv_data, drv_data->clear_sr);
629 reset_sccr1(drv_data);
630 if (!pxa25x_ssp_comp(drv_data))
631 pxa2xx_spi_write(drv_data, SSTO, 0);
632 pxa2xx_spi_flush(drv_data);
633 pxa2xx_spi_write(drv_data, SSCR0,
634 pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
636 dev_err(&drv_data->pdev->dev, "%s\n", msg);
638 drv_data->master->cur_msg->state = ERROR_STATE;
639 tasklet_schedule(&drv_data->pump_transfers);
642 static void int_transfer_complete(struct driver_data *drv_data)
644 /* Clear and disable interrupts */
645 write_SSSR_CS(drv_data, drv_data->clear_sr);
646 reset_sccr1(drv_data);
647 if (!pxa25x_ssp_comp(drv_data))
648 pxa2xx_spi_write(drv_data, SSTO, 0);
650 /* Update total byte transferred return count actual bytes read */
651 drv_data->master->cur_msg->actual_length += drv_data->len -
652 (drv_data->rx_end - drv_data->rx);
654 /* Transfer delays and chip select release are
655 * handled in pump_transfers or giveback
658 /* Move to next transfer */
659 drv_data->master->cur_msg->state = pxa2xx_spi_next_transfer(drv_data);
661 /* Schedule transfer tasklet */
662 tasklet_schedule(&drv_data->pump_transfers);
665 static irqreturn_t interrupt_transfer(struct driver_data *drv_data)
667 u32 irq_mask = (pxa2xx_spi_read(drv_data, SSCR1) & SSCR1_TIE) ?
668 drv_data->mask_sr : drv_data->mask_sr & ~SSSR_TFS;
670 u32 irq_status = pxa2xx_spi_read(drv_data, SSSR) & irq_mask;
672 if (irq_status & SSSR_ROR) {
673 int_error_stop(drv_data, "interrupt_transfer: fifo overrun");
674 return IRQ_HANDLED;
677 if (irq_status & SSSR_TINT) {
678 pxa2xx_spi_write(drv_data, SSSR, SSSR_TINT);
679 if (drv_data->read(drv_data)) {
680 int_transfer_complete(drv_data);
681 return IRQ_HANDLED;
685 /* Drain rx fifo, Fill tx fifo and prevent overruns */
686 do {
687 if (drv_data->read(drv_data)) {
688 int_transfer_complete(drv_data);
689 return IRQ_HANDLED;
691 } while (drv_data->write(drv_data));
693 if (drv_data->read(drv_data)) {
694 int_transfer_complete(drv_data);
695 return IRQ_HANDLED;
698 if (drv_data->tx == drv_data->tx_end) {
699 u32 bytes_left;
700 u32 sccr1_reg;
702 sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1);
703 sccr1_reg &= ~SSCR1_TIE;
706 * PXA25x_SSP has no timeout, set up rx threshould for the
707 * remaining RX bytes.
709 if (pxa25x_ssp_comp(drv_data)) {
710 u32 rx_thre;
712 pxa2xx_spi_clear_rx_thre(drv_data, &sccr1_reg);
714 bytes_left = drv_data->rx_end - drv_data->rx;
715 switch (drv_data->n_bytes) {
716 case 4:
717 bytes_left >>= 1;
718 case 2:
719 bytes_left >>= 1;
722 rx_thre = pxa2xx_spi_get_rx_default_thre(drv_data);
723 if (rx_thre > bytes_left)
724 rx_thre = bytes_left;
726 pxa2xx_spi_set_rx_thre(drv_data, &sccr1_reg, rx_thre);
728 pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
731 /* We did something */
732 return IRQ_HANDLED;
735 static void handle_bad_msg(struct driver_data *drv_data)
737 pxa2xx_spi_write(drv_data, SSCR0,
738 pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
739 pxa2xx_spi_write(drv_data, SSCR1,
740 pxa2xx_spi_read(drv_data, SSCR1) & ~drv_data->int_cr1);
741 if (!pxa25x_ssp_comp(drv_data))
742 pxa2xx_spi_write(drv_data, SSTO, 0);
743 write_SSSR_CS(drv_data, drv_data->clear_sr);
745 dev_err(&drv_data->pdev->dev,
746 "bad message state in interrupt handler\n");
749 static irqreturn_t ssp_int(int irq, void *dev_id)
751 struct driver_data *drv_data = dev_id;
752 u32 sccr1_reg;
753 u32 mask = drv_data->mask_sr;
754 u32 status;
757 * The IRQ might be shared with other peripherals so we must first
758 * check that are we RPM suspended or not. If we are we assume that
759 * the IRQ was not for us (we shouldn't be RPM suspended when the
760 * interrupt is enabled).
762 if (pm_runtime_suspended(&drv_data->pdev->dev))
763 return IRQ_NONE;
766 * If the device is not yet in RPM suspended state and we get an
767 * interrupt that is meant for another device, check if status bits
768 * are all set to one. That means that the device is already
769 * powered off.
771 status = pxa2xx_spi_read(drv_data, SSSR);
772 if (status == ~0)
773 return IRQ_NONE;
775 sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1);
777 /* Ignore possible writes if we don't need to write */
778 if (!(sccr1_reg & SSCR1_TIE))
779 mask &= ~SSSR_TFS;
781 /* Ignore RX timeout interrupt if it is disabled */
782 if (!(sccr1_reg & SSCR1_TINTE))
783 mask &= ~SSSR_TINT;
785 if (!(status & mask))
786 return IRQ_NONE;
788 pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg & ~drv_data->int_cr1);
789 pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
791 if (!drv_data->master->cur_msg) {
792 handle_bad_msg(drv_data);
793 /* Never fail */
794 return IRQ_HANDLED;
797 return drv_data->transfer_handler(drv_data);
801 * The Quark SPI has an additional 24 bit register (DDS_CLK_RATE) to multiply
802 * input frequency by fractions of 2^24. It also has a divider by 5.
804 * There are formulas to get baud rate value for given input frequency and
805 * divider parameters, such as DDS_CLK_RATE and SCR:
807 * Fsys = 200MHz
809 * Fssp = Fsys * DDS_CLK_RATE / 2^24 (1)
810 * Baud rate = Fsclk = Fssp / (2 * (SCR + 1)) (2)
812 * DDS_CLK_RATE either 2^n or 2^n / 5.
813 * SCR is in range 0 .. 255
815 * Divisor = 5^i * 2^j * 2 * k
816 * i = [0, 1] i = 1 iff j = 0 or j > 3
817 * j = [0, 23] j = 0 iff i = 1
818 * k = [1, 256]
819 * Special case: j = 0, i = 1: Divisor = 2 / 5
821 * Accordingly to the specification the recommended values for DDS_CLK_RATE
822 * are:
823 * Case 1: 2^n, n = [0, 23]
824 * Case 2: 2^24 * 2 / 5 (0x666666)
825 * Case 3: less than or equal to 2^24 / 5 / 16 (0x33333)
827 * In all cases the lowest possible value is better.
829 * The function calculates parameters for all cases and chooses the one closest
830 * to the asked baud rate.
832 static unsigned int quark_x1000_get_clk_div(int rate, u32 *dds)
834 unsigned long xtal = 200000000;
835 unsigned long fref = xtal / 2; /* mandatory division by 2,
836 see (2) */
837 /* case 3 */
838 unsigned long fref1 = fref / 2; /* case 1 */
839 unsigned long fref2 = fref * 2 / 5; /* case 2 */
840 unsigned long scale;
841 unsigned long q, q1, q2;
842 long r, r1, r2;
843 u32 mul;
845 /* Case 1 */
847 /* Set initial value for DDS_CLK_RATE */
848 mul = (1 << 24) >> 1;
850 /* Calculate initial quot */
851 q1 = DIV_ROUND_UP(fref1, rate);
853 /* Scale q1 if it's too big */
854 if (q1 > 256) {
855 /* Scale q1 to range [1, 512] */
856 scale = fls_long(q1 - 1);
857 if (scale > 9) {
858 q1 >>= scale - 9;
859 mul >>= scale - 9;
862 /* Round the result if we have a remainder */
863 q1 += q1 & 1;
866 /* Decrease DDS_CLK_RATE as much as we can without loss in precision */
867 scale = __ffs(q1);
868 q1 >>= scale;
869 mul >>= scale;
871 /* Get the remainder */
872 r1 = abs(fref1 / (1 << (24 - fls_long(mul))) / q1 - rate);
874 /* Case 2 */
876 q2 = DIV_ROUND_UP(fref2, rate);
877 r2 = abs(fref2 / q2 - rate);
880 * Choose the best between two: less remainder we have the better. We
881 * can't go case 2 if q2 is greater than 256 since SCR register can
882 * hold only values 0 .. 255.
884 if (r2 >= r1 || q2 > 256) {
885 /* case 1 is better */
886 r = r1;
887 q = q1;
888 } else {
889 /* case 2 is better */
890 r = r2;
891 q = q2;
892 mul = (1 << 24) * 2 / 5;
895 /* Check case 3 only if the divisor is big enough */
896 if (fref / rate >= 80) {
897 u64 fssp;
898 u32 m;
900 /* Calculate initial quot */
901 q1 = DIV_ROUND_UP(fref, rate);
902 m = (1 << 24) / q1;
904 /* Get the remainder */
905 fssp = (u64)fref * m;
906 do_div(fssp, 1 << 24);
907 r1 = abs(fssp - rate);
909 /* Choose this one if it suits better */
910 if (r1 < r) {
911 /* case 3 is better */
912 q = 1;
913 mul = m;
917 *dds = mul;
918 return q - 1;
921 static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate)
923 unsigned long ssp_clk = drv_data->master->max_speed_hz;
924 const struct ssp_device *ssp = drv_data->ssp;
926 rate = min_t(int, ssp_clk, rate);
928 if (ssp->type == PXA25x_SSP || ssp->type == CE4100_SSP)
929 return (ssp_clk / (2 * rate) - 1) & 0xff;
930 else
931 return (ssp_clk / rate - 1) & 0xfff;
934 static unsigned int pxa2xx_ssp_get_clk_div(struct driver_data *drv_data,
935 int rate)
937 struct chip_data *chip =
938 spi_get_ctldata(drv_data->master->cur_msg->spi);
939 unsigned int clk_div;
941 switch (drv_data->ssp_type) {
942 case QUARK_X1000_SSP:
943 clk_div = quark_x1000_get_clk_div(rate, &chip->dds_rate);
944 break;
945 default:
946 clk_div = ssp_get_clk_div(drv_data, rate);
947 break;
949 return clk_div << 8;
952 static bool pxa2xx_spi_can_dma(struct spi_master *master,
953 struct spi_device *spi,
954 struct spi_transfer *xfer)
956 struct chip_data *chip = spi_get_ctldata(spi);
958 return chip->enable_dma &&
959 xfer->len <= MAX_DMA_LEN &&
960 xfer->len >= chip->dma_burst_size;
963 static void pump_transfers(unsigned long data)
965 struct driver_data *drv_data = (struct driver_data *)data;
966 struct spi_master *master = drv_data->master;
967 struct spi_message *message = master->cur_msg;
968 struct chip_data *chip = spi_get_ctldata(message->spi);
969 u32 dma_thresh = chip->dma_threshold;
970 u32 dma_burst = chip->dma_burst_size;
971 u32 change_mask = pxa2xx_spi_get_ssrc1_change_mask(drv_data);
972 struct spi_transfer *transfer;
973 struct spi_transfer *previous;
974 u32 clk_div;
975 u8 bits;
976 u32 speed;
977 u32 cr0;
978 u32 cr1;
979 int err;
980 int dma_mapped;
982 /* Get current state information */
983 transfer = drv_data->cur_transfer;
985 /* Handle for abort */
986 if (message->state == ERROR_STATE) {
987 message->status = -EIO;
988 giveback(drv_data);
989 return;
992 /* Handle end of message */
993 if (message->state == DONE_STATE) {
994 message->status = 0;
995 giveback(drv_data);
996 return;
999 /* Delay if requested at end of transfer before CS change */
1000 if (message->state == RUNNING_STATE) {
1001 previous = list_entry(transfer->transfer_list.prev,
1002 struct spi_transfer,
1003 transfer_list);
1004 if (previous->delay_usecs)
1005 udelay(previous->delay_usecs);
1007 /* Drop chip select only if cs_change is requested */
1008 if (previous->cs_change)
1009 cs_deassert(drv_data);
1012 /* Check if we can DMA this transfer */
1013 if (transfer->len > MAX_DMA_LEN && chip->enable_dma) {
1015 /* reject already-mapped transfers; PIO won't always work */
1016 if (message->is_dma_mapped
1017 || transfer->rx_dma || transfer->tx_dma) {
1018 dev_err(&drv_data->pdev->dev,
1019 "pump_transfers: mapped transfer length of "
1020 "%u is greater than %d\n",
1021 transfer->len, MAX_DMA_LEN);
1022 message->status = -EINVAL;
1023 giveback(drv_data);
1024 return;
1027 /* warn ... we force this to PIO mode */
1028 dev_warn_ratelimited(&message->spi->dev,
1029 "pump_transfers: DMA disabled for transfer length %ld "
1030 "greater than %d\n",
1031 (long)drv_data->len, MAX_DMA_LEN);
1034 /* Setup the transfer state based on the type of transfer */
1035 if (pxa2xx_spi_flush(drv_data) == 0) {
1036 dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
1037 message->status = -EIO;
1038 giveback(drv_data);
1039 return;
1041 drv_data->n_bytes = chip->n_bytes;
1042 drv_data->tx = (void *)transfer->tx_buf;
1043 drv_data->tx_end = drv_data->tx + transfer->len;
1044 drv_data->rx = transfer->rx_buf;
1045 drv_data->rx_end = drv_data->rx + transfer->len;
1046 drv_data->len = transfer->len;
1047 drv_data->write = drv_data->tx ? chip->write : null_writer;
1048 drv_data->read = drv_data->rx ? chip->read : null_reader;
1050 /* Change speed and bit per word on a per transfer */
1051 bits = transfer->bits_per_word;
1052 speed = transfer->speed_hz;
1054 clk_div = pxa2xx_ssp_get_clk_div(drv_data, speed);
1056 if (bits <= 8) {
1057 drv_data->n_bytes = 1;
1058 drv_data->read = drv_data->read != null_reader ?
1059 u8_reader : null_reader;
1060 drv_data->write = drv_data->write != null_writer ?
1061 u8_writer : null_writer;
1062 } else if (bits <= 16) {
1063 drv_data->n_bytes = 2;
1064 drv_data->read = drv_data->read != null_reader ?
1065 u16_reader : null_reader;
1066 drv_data->write = drv_data->write != null_writer ?
1067 u16_writer : null_writer;
1068 } else if (bits <= 32) {
1069 drv_data->n_bytes = 4;
1070 drv_data->read = drv_data->read != null_reader ?
1071 u32_reader : null_reader;
1072 drv_data->write = drv_data->write != null_writer ?
1073 u32_writer : null_writer;
1076 * if bits/word is changed in dma mode, then must check the
1077 * thresholds and burst also
1079 if (chip->enable_dma) {
1080 if (pxa2xx_spi_set_dma_burst_and_threshold(chip,
1081 message->spi,
1082 bits, &dma_burst,
1083 &dma_thresh))
1084 dev_warn_ratelimited(&message->spi->dev,
1085 "pump_transfers: DMA burst size reduced to match bits_per_word\n");
1088 message->state = RUNNING_STATE;
1090 dma_mapped = master->can_dma &&
1091 master->can_dma(master, message->spi, transfer) &&
1092 master->cur_msg_mapped;
1093 if (dma_mapped) {
1095 /* Ensure we have the correct interrupt handler */
1096 drv_data->transfer_handler = pxa2xx_spi_dma_transfer;
1098 err = pxa2xx_spi_dma_prepare(drv_data, dma_burst);
1099 if (err) {
1100 message->status = err;
1101 giveback(drv_data);
1102 return;
1105 /* Clear status and start DMA engine */
1106 cr1 = chip->cr1 | dma_thresh | drv_data->dma_cr1;
1107 pxa2xx_spi_write(drv_data, SSSR, drv_data->clear_sr);
1109 pxa2xx_spi_dma_start(drv_data);
1110 } else {
1111 /* Ensure we have the correct interrupt handler */
1112 drv_data->transfer_handler = interrupt_transfer;
1114 /* Clear status */
1115 cr1 = chip->cr1 | chip->threshold | drv_data->int_cr1;
1116 write_SSSR_CS(drv_data, drv_data->clear_sr);
1119 /* NOTE: PXA25x_SSP _could_ use external clocking ... */
1120 cr0 = pxa2xx_configure_sscr0(drv_data, clk_div, bits);
1121 if (!pxa25x_ssp_comp(drv_data))
1122 dev_dbg(&message->spi->dev, "%u Hz actual, %s\n",
1123 master->max_speed_hz
1124 / (1 + ((cr0 & SSCR0_SCR(0xfff)) >> 8)),
1125 dma_mapped ? "DMA" : "PIO");
1126 else
1127 dev_dbg(&message->spi->dev, "%u Hz actual, %s\n",
1128 master->max_speed_hz / 2
1129 / (1 + ((cr0 & SSCR0_SCR(0x0ff)) >> 8)),
1130 dma_mapped ? "DMA" : "PIO");
1132 if (is_lpss_ssp(drv_data)) {
1133 if ((pxa2xx_spi_read(drv_data, SSIRF) & 0xff)
1134 != chip->lpss_rx_threshold)
1135 pxa2xx_spi_write(drv_data, SSIRF,
1136 chip->lpss_rx_threshold);
1137 if ((pxa2xx_spi_read(drv_data, SSITF) & 0xffff)
1138 != chip->lpss_tx_threshold)
1139 pxa2xx_spi_write(drv_data, SSITF,
1140 chip->lpss_tx_threshold);
1143 if (is_quark_x1000_ssp(drv_data) &&
1144 (pxa2xx_spi_read(drv_data, DDS_RATE) != chip->dds_rate))
1145 pxa2xx_spi_write(drv_data, DDS_RATE, chip->dds_rate);
1147 /* see if we need to reload the config registers */
1148 if ((pxa2xx_spi_read(drv_data, SSCR0) != cr0)
1149 || (pxa2xx_spi_read(drv_data, SSCR1) & change_mask)
1150 != (cr1 & change_mask)) {
1151 /* stop the SSP, and update the other bits */
1152 pxa2xx_spi_write(drv_data, SSCR0, cr0 & ~SSCR0_SSE);
1153 if (!pxa25x_ssp_comp(drv_data))
1154 pxa2xx_spi_write(drv_data, SSTO, chip->timeout);
1155 /* first set CR1 without interrupt and service enables */
1156 pxa2xx_spi_write(drv_data, SSCR1, cr1 & change_mask);
1157 /* restart the SSP */
1158 pxa2xx_spi_write(drv_data, SSCR0, cr0);
1160 } else {
1161 if (!pxa25x_ssp_comp(drv_data))
1162 pxa2xx_spi_write(drv_data, SSTO, chip->timeout);
1165 cs_assert(drv_data);
1167 /* after chip select, release the data by enabling service
1168 * requests and interrupts, without changing any mode bits */
1169 pxa2xx_spi_write(drv_data, SSCR1, cr1);
1172 static int pxa2xx_spi_transfer_one_message(struct spi_master *master,
1173 struct spi_message *msg)
1175 struct driver_data *drv_data = spi_master_get_devdata(master);
1177 /* Initial message state*/
1178 msg->state = START_STATE;
1179 drv_data->cur_transfer = list_entry(msg->transfers.next,
1180 struct spi_transfer,
1181 transfer_list);
1183 /* Mark as busy and launch transfers */
1184 tasklet_schedule(&drv_data->pump_transfers);
1185 return 0;
1188 static int pxa2xx_spi_unprepare_transfer(struct spi_master *master)
1190 struct driver_data *drv_data = spi_master_get_devdata(master);
1192 /* Disable the SSP now */
1193 pxa2xx_spi_write(drv_data, SSCR0,
1194 pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
1196 return 0;
1199 static int setup_cs(struct spi_device *spi, struct chip_data *chip,
1200 struct pxa2xx_spi_chip *chip_info)
1202 struct driver_data *drv_data = spi_master_get_devdata(spi->master);
1203 int err = 0;
1205 if (chip == NULL)
1206 return 0;
1208 if (drv_data->cs_gpiods) {
1209 struct gpio_desc *gpiod;
1211 gpiod = drv_data->cs_gpiods[spi->chip_select];
1212 if (gpiod) {
1213 chip->gpio_cs = desc_to_gpio(gpiod);
1214 chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH;
1215 gpiod_set_value(gpiod, chip->gpio_cs_inverted);
1218 return 0;
1221 if (chip_info == NULL)
1222 return 0;
1224 /* NOTE: setup() can be called multiple times, possibly with
1225 * different chip_info, release previously requested GPIO
1227 if (gpio_is_valid(chip->gpio_cs))
1228 gpio_free(chip->gpio_cs);
1230 /* If (*cs_control) is provided, ignore GPIO chip select */
1231 if (chip_info->cs_control) {
1232 chip->cs_control = chip_info->cs_control;
1233 return 0;
1236 if (gpio_is_valid(chip_info->gpio_cs)) {
1237 err = gpio_request(chip_info->gpio_cs, "SPI_CS");
1238 if (err) {
1239 dev_err(&spi->dev, "failed to request chip select GPIO%d\n",
1240 chip_info->gpio_cs);
1241 return err;
1244 chip->gpio_cs = chip_info->gpio_cs;
1245 chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH;
1247 err = gpio_direction_output(chip->gpio_cs,
1248 !chip->gpio_cs_inverted);
1251 return err;
1254 static int setup(struct spi_device *spi)
1256 struct pxa2xx_spi_chip *chip_info;
1257 struct chip_data *chip;
1258 const struct lpss_config *config;
1259 struct driver_data *drv_data = spi_master_get_devdata(spi->master);
1260 uint tx_thres, tx_hi_thres, rx_thres;
1262 switch (drv_data->ssp_type) {
1263 case QUARK_X1000_SSP:
1264 tx_thres = TX_THRESH_QUARK_X1000_DFLT;
1265 tx_hi_thres = 0;
1266 rx_thres = RX_THRESH_QUARK_X1000_DFLT;
1267 break;
1268 case CE4100_SSP:
1269 tx_thres = TX_THRESH_CE4100_DFLT;
1270 tx_hi_thres = 0;
1271 rx_thres = RX_THRESH_CE4100_DFLT;
1272 break;
1273 case LPSS_LPT_SSP:
1274 case LPSS_BYT_SSP:
1275 case LPSS_BSW_SSP:
1276 case LPSS_SPT_SSP:
1277 case LPSS_BXT_SSP:
1278 config = lpss_get_config(drv_data);
1279 tx_thres = config->tx_threshold_lo;
1280 tx_hi_thres = config->tx_threshold_hi;
1281 rx_thres = config->rx_threshold;
1282 break;
1283 default:
1284 tx_thres = TX_THRESH_DFLT;
1285 tx_hi_thres = 0;
1286 rx_thres = RX_THRESH_DFLT;
1287 break;
1290 /* Only alloc on first setup */
1291 chip = spi_get_ctldata(spi);
1292 if (!chip) {
1293 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1294 if (!chip)
1295 return -ENOMEM;
1297 if (drv_data->ssp_type == CE4100_SSP) {
1298 if (spi->chip_select > 4) {
1299 dev_err(&spi->dev,
1300 "failed setup: cs number must not be > 4.\n");
1301 kfree(chip);
1302 return -EINVAL;
1305 chip->frm = spi->chip_select;
1306 } else
1307 chip->gpio_cs = -1;
1308 chip->enable_dma = drv_data->master_info->enable_dma;
1309 chip->timeout = TIMOUT_DFLT;
1312 /* protocol drivers may change the chip settings, so...
1313 * if chip_info exists, use it */
1314 chip_info = spi->controller_data;
1316 /* chip_info isn't always needed */
1317 chip->cr1 = 0;
1318 if (chip_info) {
1319 if (chip_info->timeout)
1320 chip->timeout = chip_info->timeout;
1321 if (chip_info->tx_threshold)
1322 tx_thres = chip_info->tx_threshold;
1323 if (chip_info->tx_hi_threshold)
1324 tx_hi_thres = chip_info->tx_hi_threshold;
1325 if (chip_info->rx_threshold)
1326 rx_thres = chip_info->rx_threshold;
1327 chip->dma_threshold = 0;
1328 if (chip_info->enable_loopback)
1329 chip->cr1 = SSCR1_LBM;
1332 chip->lpss_rx_threshold = SSIRF_RxThresh(rx_thres);
1333 chip->lpss_tx_threshold = SSITF_TxLoThresh(tx_thres)
1334 | SSITF_TxHiThresh(tx_hi_thres);
1336 /* set dma burst and threshold outside of chip_info path so that if
1337 * chip_info goes away after setting chip->enable_dma, the
1338 * burst and threshold can still respond to changes in bits_per_word */
1339 if (chip->enable_dma) {
1340 /* set up legal burst and threshold for dma */
1341 if (pxa2xx_spi_set_dma_burst_and_threshold(chip, spi,
1342 spi->bits_per_word,
1343 &chip->dma_burst_size,
1344 &chip->dma_threshold)) {
1345 dev_warn(&spi->dev,
1346 "in setup: DMA burst size reduced to match bits_per_word\n");
1350 switch (drv_data->ssp_type) {
1351 case QUARK_X1000_SSP:
1352 chip->threshold = (QUARK_X1000_SSCR1_RxTresh(rx_thres)
1353 & QUARK_X1000_SSCR1_RFT)
1354 | (QUARK_X1000_SSCR1_TxTresh(tx_thres)
1355 & QUARK_X1000_SSCR1_TFT);
1356 break;
1357 case CE4100_SSP:
1358 chip->threshold = (CE4100_SSCR1_RxTresh(rx_thres) & CE4100_SSCR1_RFT) |
1359 (CE4100_SSCR1_TxTresh(tx_thres) & CE4100_SSCR1_TFT);
1360 break;
1361 default:
1362 chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) |
1363 (SSCR1_TxTresh(tx_thres) & SSCR1_TFT);
1364 break;
1367 chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH);
1368 chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0)
1369 | (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0);
1371 if (spi->mode & SPI_LOOP)
1372 chip->cr1 |= SSCR1_LBM;
1374 if (spi->bits_per_word <= 8) {
1375 chip->n_bytes = 1;
1376 chip->read = u8_reader;
1377 chip->write = u8_writer;
1378 } else if (spi->bits_per_word <= 16) {
1379 chip->n_bytes = 2;
1380 chip->read = u16_reader;
1381 chip->write = u16_writer;
1382 } else if (spi->bits_per_word <= 32) {
1383 chip->n_bytes = 4;
1384 chip->read = u32_reader;
1385 chip->write = u32_writer;
1388 spi_set_ctldata(spi, chip);
1390 if (drv_data->ssp_type == CE4100_SSP)
1391 return 0;
1393 return setup_cs(spi, chip, chip_info);
1396 static void cleanup(struct spi_device *spi)
1398 struct chip_data *chip = spi_get_ctldata(spi);
1399 struct driver_data *drv_data = spi_master_get_devdata(spi->master);
1401 if (!chip)
1402 return;
1404 if (drv_data->ssp_type != CE4100_SSP && !drv_data->cs_gpiods &&
1405 gpio_is_valid(chip->gpio_cs))
1406 gpio_free(chip->gpio_cs);
1408 kfree(chip);
1411 #ifdef CONFIG_PCI
1412 #ifdef CONFIG_ACPI
1414 static const struct acpi_device_id pxa2xx_spi_acpi_match[] = {
1415 { "INT33C0", LPSS_LPT_SSP },
1416 { "INT33C1", LPSS_LPT_SSP },
1417 { "INT3430", LPSS_LPT_SSP },
1418 { "INT3431", LPSS_LPT_SSP },
1419 { "80860F0E", LPSS_BYT_SSP },
1420 { "8086228E", LPSS_BSW_SSP },
1421 { },
1423 MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match);
1425 static int pxa2xx_spi_get_port_id(struct acpi_device *adev)
1427 unsigned int devid;
1428 int port_id = -1;
1430 if (adev && adev->pnp.unique_id &&
1431 !kstrtouint(adev->pnp.unique_id, 0, &devid))
1432 port_id = devid;
1433 return port_id;
1435 #else /* !CONFIG_ACPI */
1436 static int pxa2xx_spi_get_port_id(struct acpi_device *adev)
1438 return -1;
1440 #endif
1443 * PCI IDs of compound devices that integrate both host controller and private
1444 * integrated DMA engine. Please note these are not used in module
1445 * autoloading and probing in this module but matching the LPSS SSP type.
1447 static const struct pci_device_id pxa2xx_spi_pci_compound_match[] = {
1448 /* SPT-LP */
1449 { PCI_VDEVICE(INTEL, 0x9d29), LPSS_SPT_SSP },
1450 { PCI_VDEVICE(INTEL, 0x9d2a), LPSS_SPT_SSP },
1451 /* SPT-H */
1452 { PCI_VDEVICE(INTEL, 0xa129), LPSS_SPT_SSP },
1453 { PCI_VDEVICE(INTEL, 0xa12a), LPSS_SPT_SSP },
1454 /* KBL-H */
1455 { PCI_VDEVICE(INTEL, 0xa2a9), LPSS_SPT_SSP },
1456 { PCI_VDEVICE(INTEL, 0xa2aa), LPSS_SPT_SSP },
1457 /* BXT A-Step */
1458 { PCI_VDEVICE(INTEL, 0x0ac2), LPSS_BXT_SSP },
1459 { PCI_VDEVICE(INTEL, 0x0ac4), LPSS_BXT_SSP },
1460 { PCI_VDEVICE(INTEL, 0x0ac6), LPSS_BXT_SSP },
1461 /* BXT B-Step */
1462 { PCI_VDEVICE(INTEL, 0x1ac2), LPSS_BXT_SSP },
1463 { PCI_VDEVICE(INTEL, 0x1ac4), LPSS_BXT_SSP },
1464 { PCI_VDEVICE(INTEL, 0x1ac6), LPSS_BXT_SSP },
1465 /* GLK */
1466 { PCI_VDEVICE(INTEL, 0x31c2), LPSS_BXT_SSP },
1467 { PCI_VDEVICE(INTEL, 0x31c4), LPSS_BXT_SSP },
1468 { PCI_VDEVICE(INTEL, 0x31c6), LPSS_BXT_SSP },
1469 /* APL */
1470 { PCI_VDEVICE(INTEL, 0x5ac2), LPSS_BXT_SSP },
1471 { PCI_VDEVICE(INTEL, 0x5ac4), LPSS_BXT_SSP },
1472 { PCI_VDEVICE(INTEL, 0x5ac6), LPSS_BXT_SSP },
1473 { },
1476 static bool pxa2xx_spi_idma_filter(struct dma_chan *chan, void *param)
1478 struct device *dev = param;
1480 if (dev != chan->device->dev->parent)
1481 return false;
1483 return true;
1486 static struct pxa2xx_spi_master *
1487 pxa2xx_spi_init_pdata(struct platform_device *pdev)
1489 struct pxa2xx_spi_master *pdata;
1490 struct acpi_device *adev;
1491 struct ssp_device *ssp;
1492 struct resource *res;
1493 const struct acpi_device_id *adev_id = NULL;
1494 const struct pci_device_id *pcidev_id = NULL;
1495 int type;
1497 adev = ACPI_COMPANION(&pdev->dev);
1499 if (dev_is_pci(pdev->dev.parent))
1500 pcidev_id = pci_match_id(pxa2xx_spi_pci_compound_match,
1501 to_pci_dev(pdev->dev.parent));
1502 else if (adev)
1503 adev_id = acpi_match_device(pdev->dev.driver->acpi_match_table,
1504 &pdev->dev);
1505 else
1506 return NULL;
1508 if (adev_id)
1509 type = (int)adev_id->driver_data;
1510 else if (pcidev_id)
1511 type = (int)pcidev_id->driver_data;
1512 else
1513 return NULL;
1515 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
1516 if (!pdata)
1517 return NULL;
1519 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1520 if (!res)
1521 return NULL;
1523 ssp = &pdata->ssp;
1525 ssp->phys_base = res->start;
1526 ssp->mmio_base = devm_ioremap_resource(&pdev->dev, res);
1527 if (IS_ERR(ssp->mmio_base))
1528 return NULL;
1530 if (pcidev_id) {
1531 pdata->tx_param = pdev->dev.parent;
1532 pdata->rx_param = pdev->dev.parent;
1533 pdata->dma_filter = pxa2xx_spi_idma_filter;
1536 ssp->clk = devm_clk_get(&pdev->dev, NULL);
1537 ssp->irq = platform_get_irq(pdev, 0);
1538 ssp->type = type;
1539 ssp->pdev = pdev;
1540 ssp->port_id = pxa2xx_spi_get_port_id(adev);
1542 pdata->num_chipselect = 1;
1543 pdata->enable_dma = true;
1545 return pdata;
1548 #else /* !CONFIG_PCI */
1549 static inline struct pxa2xx_spi_master *
1550 pxa2xx_spi_init_pdata(struct platform_device *pdev)
1552 return NULL;
1554 #endif
1556 static int pxa2xx_spi_fw_translate_cs(struct spi_master *master, unsigned cs)
1558 struct driver_data *drv_data = spi_master_get_devdata(master);
1560 if (has_acpi_companion(&drv_data->pdev->dev)) {
1561 switch (drv_data->ssp_type) {
1563 * For Atoms the ACPI DeviceSelection used by the Windows
1564 * driver starts from 1 instead of 0 so translate it here
1565 * to match what Linux expects.
1567 case LPSS_BYT_SSP:
1568 case LPSS_BSW_SSP:
1569 return cs - 1;
1571 default:
1572 break;
1576 return cs;
1579 static int pxa2xx_spi_probe(struct platform_device *pdev)
1581 struct device *dev = &pdev->dev;
1582 struct pxa2xx_spi_master *platform_info;
1583 struct spi_master *master;
1584 struct driver_data *drv_data;
1585 struct ssp_device *ssp;
1586 const struct lpss_config *config;
1587 int status, count;
1588 u32 tmp;
1590 platform_info = dev_get_platdata(dev);
1591 if (!platform_info) {
1592 platform_info = pxa2xx_spi_init_pdata(pdev);
1593 if (!platform_info) {
1594 dev_err(&pdev->dev, "missing platform data\n");
1595 return -ENODEV;
1599 ssp = pxa_ssp_request(pdev->id, pdev->name);
1600 if (!ssp)
1601 ssp = &platform_info->ssp;
1603 if (!ssp->mmio_base) {
1604 dev_err(&pdev->dev, "failed to get ssp\n");
1605 return -ENODEV;
1608 master = spi_alloc_master(dev, sizeof(struct driver_data));
1609 if (!master) {
1610 dev_err(&pdev->dev, "cannot alloc spi_master\n");
1611 pxa_ssp_free(ssp);
1612 return -ENOMEM;
1614 drv_data = spi_master_get_devdata(master);
1615 drv_data->master = master;
1616 drv_data->master_info = platform_info;
1617 drv_data->pdev = pdev;
1618 drv_data->ssp = ssp;
1620 master->dev.of_node = pdev->dev.of_node;
1621 /* the spi->mode bits understood by this driver: */
1622 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
1624 master->bus_num = ssp->port_id;
1625 master->dma_alignment = DMA_ALIGNMENT;
1626 master->cleanup = cleanup;
1627 master->setup = setup;
1628 master->transfer_one_message = pxa2xx_spi_transfer_one_message;
1629 master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer;
1630 master->fw_translate_cs = pxa2xx_spi_fw_translate_cs;
1631 master->auto_runtime_pm = true;
1632 master->flags = SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX;
1634 drv_data->ssp_type = ssp->type;
1636 drv_data->ioaddr = ssp->mmio_base;
1637 drv_data->ssdr_physical = ssp->phys_base + SSDR;
1638 if (pxa25x_ssp_comp(drv_data)) {
1639 switch (drv_data->ssp_type) {
1640 case QUARK_X1000_SSP:
1641 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1642 break;
1643 default:
1644 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
1645 break;
1648 drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE;
1649 drv_data->dma_cr1 = 0;
1650 drv_data->clear_sr = SSSR_ROR;
1651 drv_data->mask_sr = SSSR_RFS | SSSR_TFS | SSSR_ROR;
1652 } else {
1653 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1654 drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE | SSCR1_TINTE;
1655 drv_data->dma_cr1 = DEFAULT_DMA_CR1;
1656 drv_data->clear_sr = SSSR_ROR | SSSR_TINT;
1657 drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS | SSSR_ROR;
1660 status = request_irq(ssp->irq, ssp_int, IRQF_SHARED, dev_name(dev),
1661 drv_data);
1662 if (status < 0) {
1663 dev_err(&pdev->dev, "cannot get IRQ %d\n", ssp->irq);
1664 goto out_error_master_alloc;
1667 /* Setup DMA if requested */
1668 if (platform_info->enable_dma) {
1669 status = pxa2xx_spi_dma_setup(drv_data);
1670 if (status) {
1671 dev_dbg(dev, "no DMA channels available, using PIO\n");
1672 platform_info->enable_dma = false;
1673 } else {
1674 master->can_dma = pxa2xx_spi_can_dma;
1678 /* Enable SOC clock */
1679 clk_prepare_enable(ssp->clk);
1681 master->max_speed_hz = clk_get_rate(ssp->clk);
1683 /* Load default SSP configuration */
1684 pxa2xx_spi_write(drv_data, SSCR0, 0);
1685 switch (drv_data->ssp_type) {
1686 case QUARK_X1000_SSP:
1687 tmp = QUARK_X1000_SSCR1_RxTresh(RX_THRESH_QUARK_X1000_DFLT) |
1688 QUARK_X1000_SSCR1_TxTresh(TX_THRESH_QUARK_X1000_DFLT);
1689 pxa2xx_spi_write(drv_data, SSCR1, tmp);
1691 /* using the Motorola SPI protocol and use 8 bit frame */
1692 tmp = QUARK_X1000_SSCR0_Motorola | QUARK_X1000_SSCR0_DataSize(8);
1693 pxa2xx_spi_write(drv_data, SSCR0, tmp);
1694 break;
1695 case CE4100_SSP:
1696 tmp = CE4100_SSCR1_RxTresh(RX_THRESH_CE4100_DFLT) |
1697 CE4100_SSCR1_TxTresh(TX_THRESH_CE4100_DFLT);
1698 pxa2xx_spi_write(drv_data, SSCR1, tmp);
1699 tmp = SSCR0_SCR(2) | SSCR0_Motorola | SSCR0_DataSize(8);
1700 pxa2xx_spi_write(drv_data, SSCR0, tmp);
1701 break;
1702 default:
1703 tmp = SSCR1_RxTresh(RX_THRESH_DFLT) |
1704 SSCR1_TxTresh(TX_THRESH_DFLT);
1705 pxa2xx_spi_write(drv_data, SSCR1, tmp);
1706 tmp = SSCR0_SCR(2) | SSCR0_Motorola | SSCR0_DataSize(8);
1707 pxa2xx_spi_write(drv_data, SSCR0, tmp);
1708 break;
1711 if (!pxa25x_ssp_comp(drv_data))
1712 pxa2xx_spi_write(drv_data, SSTO, 0);
1714 if (!is_quark_x1000_ssp(drv_data))
1715 pxa2xx_spi_write(drv_data, SSPSP, 0);
1717 if (is_lpss_ssp(drv_data)) {
1718 lpss_ssp_setup(drv_data);
1719 config = lpss_get_config(drv_data);
1720 if (config->reg_capabilities >= 0) {
1721 tmp = __lpss_ssp_read_priv(drv_data,
1722 config->reg_capabilities);
1723 tmp &= LPSS_CAPS_CS_EN_MASK;
1724 tmp >>= LPSS_CAPS_CS_EN_SHIFT;
1725 platform_info->num_chipselect = ffz(tmp);
1726 } else if (config->cs_num) {
1727 platform_info->num_chipselect = config->cs_num;
1730 master->num_chipselect = platform_info->num_chipselect;
1732 count = gpiod_count(&pdev->dev, "cs");
1733 if (count > 0) {
1734 int i;
1736 master->num_chipselect = max_t(int, count,
1737 master->num_chipselect);
1739 drv_data->cs_gpiods = devm_kcalloc(&pdev->dev,
1740 master->num_chipselect, sizeof(struct gpio_desc *),
1741 GFP_KERNEL);
1742 if (!drv_data->cs_gpiods) {
1743 status = -ENOMEM;
1744 goto out_error_clock_enabled;
1747 for (i = 0; i < master->num_chipselect; i++) {
1748 struct gpio_desc *gpiod;
1750 gpiod = devm_gpiod_get_index(dev, "cs", i,
1751 GPIOD_OUT_HIGH);
1752 if (IS_ERR(gpiod)) {
1753 /* Means use native chip select */
1754 if (PTR_ERR(gpiod) == -ENOENT)
1755 continue;
1757 status = (int)PTR_ERR(gpiod);
1758 goto out_error_clock_enabled;
1759 } else {
1760 drv_data->cs_gpiods[i] = gpiod;
1765 tasklet_init(&drv_data->pump_transfers, pump_transfers,
1766 (unsigned long)drv_data);
1768 pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
1769 pm_runtime_use_autosuspend(&pdev->dev);
1770 pm_runtime_set_active(&pdev->dev);
1771 pm_runtime_enable(&pdev->dev);
1773 /* Register with the SPI framework */
1774 platform_set_drvdata(pdev, drv_data);
1775 status = devm_spi_register_master(&pdev->dev, master);
1776 if (status != 0) {
1777 dev_err(&pdev->dev, "problem registering spi master\n");
1778 goto out_error_clock_enabled;
1781 return status;
1783 out_error_clock_enabled:
1784 clk_disable_unprepare(ssp->clk);
1785 pxa2xx_spi_dma_release(drv_data);
1786 free_irq(ssp->irq, drv_data);
1788 out_error_master_alloc:
1789 spi_master_put(master);
1790 pxa_ssp_free(ssp);
1791 return status;
1794 static int pxa2xx_spi_remove(struct platform_device *pdev)
1796 struct driver_data *drv_data = platform_get_drvdata(pdev);
1797 struct ssp_device *ssp;
1799 if (!drv_data)
1800 return 0;
1801 ssp = drv_data->ssp;
1803 pm_runtime_get_sync(&pdev->dev);
1805 /* Disable the SSP at the peripheral and SOC level */
1806 pxa2xx_spi_write(drv_data, SSCR0, 0);
1807 clk_disable_unprepare(ssp->clk);
1809 /* Release DMA */
1810 if (drv_data->master_info->enable_dma)
1811 pxa2xx_spi_dma_release(drv_data);
1813 pm_runtime_put_noidle(&pdev->dev);
1814 pm_runtime_disable(&pdev->dev);
1816 /* Release IRQ */
1817 free_irq(ssp->irq, drv_data);
1819 /* Release SSP */
1820 pxa_ssp_free(ssp);
1822 return 0;
1825 static void pxa2xx_spi_shutdown(struct platform_device *pdev)
1827 int status = 0;
1829 if ((status = pxa2xx_spi_remove(pdev)) != 0)
1830 dev_err(&pdev->dev, "shutdown failed with %d\n", status);
1833 #ifdef CONFIG_PM_SLEEP
1834 static int pxa2xx_spi_suspend(struct device *dev)
1836 struct driver_data *drv_data = dev_get_drvdata(dev);
1837 struct ssp_device *ssp = drv_data->ssp;
1838 int status;
1840 status = spi_master_suspend(drv_data->master);
1841 if (status != 0)
1842 return status;
1843 pxa2xx_spi_write(drv_data, SSCR0, 0);
1845 if (!pm_runtime_suspended(dev))
1846 clk_disable_unprepare(ssp->clk);
1848 return 0;
1851 static int pxa2xx_spi_resume(struct device *dev)
1853 struct driver_data *drv_data = dev_get_drvdata(dev);
1854 struct ssp_device *ssp = drv_data->ssp;
1855 int status;
1857 /* Enable the SSP clock */
1858 if (!pm_runtime_suspended(dev))
1859 clk_prepare_enable(ssp->clk);
1861 /* Restore LPSS private register bits */
1862 if (is_lpss_ssp(drv_data))
1863 lpss_ssp_setup(drv_data);
1865 /* Start the queue running */
1866 status = spi_master_resume(drv_data->master);
1867 if (status != 0) {
1868 dev_err(dev, "problem starting queue (%d)\n", status);
1869 return status;
1872 return 0;
1874 #endif
1876 #ifdef CONFIG_PM
1877 static int pxa2xx_spi_runtime_suspend(struct device *dev)
1879 struct driver_data *drv_data = dev_get_drvdata(dev);
1881 clk_disable_unprepare(drv_data->ssp->clk);
1882 return 0;
1885 static int pxa2xx_spi_runtime_resume(struct device *dev)
1887 struct driver_data *drv_data = dev_get_drvdata(dev);
1889 clk_prepare_enable(drv_data->ssp->clk);
1890 return 0;
1892 #endif
1894 static const struct dev_pm_ops pxa2xx_spi_pm_ops = {
1895 SET_SYSTEM_SLEEP_PM_OPS(pxa2xx_spi_suspend, pxa2xx_spi_resume)
1896 SET_RUNTIME_PM_OPS(pxa2xx_spi_runtime_suspend,
1897 pxa2xx_spi_runtime_resume, NULL)
1900 static struct platform_driver driver = {
1901 .driver = {
1902 .name = "pxa2xx-spi",
1903 .pm = &pxa2xx_spi_pm_ops,
1904 .acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match),
1906 .probe = pxa2xx_spi_probe,
1907 .remove = pxa2xx_spi_remove,
1908 .shutdown = pxa2xx_spi_shutdown,
1911 static int __init pxa2xx_spi_init(void)
1913 return platform_driver_register(&driver);
1915 subsys_initcall(pxa2xx_spi_init);
1917 static void __exit pxa2xx_spi_exit(void)
1919 platform_driver_unregister(&driver);
1921 module_exit(pxa2xx_spi_exit);