xref: /openbmc/linux/drivers/spi/spi-pxa2xx.c (revision 609e478b)
1 /*
2  * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
3  * Copyright (C) 2013, Intel Corporation
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18  */
19 
20 #include <linux/init.h>
21 #include <linux/module.h>
22 #include <linux/device.h>
23 #include <linux/ioport.h>
24 #include <linux/errno.h>
25 #include <linux/err.h>
26 #include <linux/interrupt.h>
27 #include <linux/platform_device.h>
28 #include <linux/spi/pxa2xx_spi.h>
29 #include <linux/spi/spi.h>
30 #include <linux/delay.h>
31 #include <linux/gpio.h>
32 #include <linux/slab.h>
33 #include <linux/clk.h>
34 #include <linux/pm_runtime.h>
35 #include <linux/acpi.h>
36 
37 #include <asm/io.h>
38 #include <asm/irq.h>
39 #include <asm/delay.h>
40 
41 #include "spi-pxa2xx.h"
42 
43 MODULE_AUTHOR("Stephen Street");
44 MODULE_DESCRIPTION("PXA2xx SSP SPI Controller");
45 MODULE_LICENSE("GPL");
46 MODULE_ALIAS("platform:pxa2xx-spi");
47 
48 #define MAX_BUSES 3
49 
50 #define TIMOUT_DFLT		1000
51 
52 /*
53  * for testing SSCR1 changes that require SSP restart, basically
54  * everything except the service and interrupt enables, the pxa270 developer
55  * manual says only SSCR1_SCFR, SSCR1_SPH, SSCR1_SPO need to be in this
56  * list, but the PXA255 dev man says all bits without really meaning the
57  * service and interrupt enables
58  */
59 #define SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_SCFR \
60 				| SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \
61 				| SSCR1_SFRMDIR | SSCR1_RWOT | SSCR1_TRAIL \
62 				| SSCR1_IFS | SSCR1_STRF | SSCR1_EFWR \
63 				| SSCR1_RFT | SSCR1_TFT | SSCR1_MWDS \
64 				| SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
65 
66 #define LPSS_RX_THRESH_DFLT	64
67 #define LPSS_TX_LOTHRESH_DFLT	160
68 #define LPSS_TX_HITHRESH_DFLT	224
69 
70 /* Offset from drv_data->lpss_base */
71 #define GENERAL_REG		0x08
72 #define GENERAL_REG_RXTO_HOLDOFF_DISABLE BIT(24)
73 #define SSP_REG			0x0c
74 #define SPI_CS_CONTROL		0x18
75 #define SPI_CS_CONTROL_SW_MODE	BIT(0)
76 #define SPI_CS_CONTROL_CS_HIGH	BIT(1)
77 
78 static bool is_lpss_ssp(const struct driver_data *drv_data)
79 {
80 	return drv_data->ssp_type == LPSS_SSP;
81 }
82 
83 /*
84  * Read and write LPSS SSP private registers. Caller must first check that
85  * is_lpss_ssp() returns true before these can be called.
86  */
87 static u32 __lpss_ssp_read_priv(struct driver_data *drv_data, unsigned offset)
88 {
89 	WARN_ON(!drv_data->lpss_base);
90 	return readl(drv_data->lpss_base + offset);
91 }
92 
93 static void __lpss_ssp_write_priv(struct driver_data *drv_data,
94 				  unsigned offset, u32 value)
95 {
96 	WARN_ON(!drv_data->lpss_base);
97 	writel(value, drv_data->lpss_base + offset);
98 }
99 
100 /*
101  * lpss_ssp_setup - perform LPSS SSP specific setup
102  * @drv_data: pointer to the driver private data
103  *
104  * Perform LPSS SSP specific setup. This function must be called first if
105  * one is going to use LPSS SSP private registers.
106  */
107 static void lpss_ssp_setup(struct driver_data *drv_data)
108 {
109 	unsigned offset = 0x400;
110 	u32 value, orig;
111 
112 	if (!is_lpss_ssp(drv_data))
113 		return;
114 
115 	/*
116 	 * Perform auto-detection of the LPSS SSP private registers. They
117 	 * can be either at 1k or 2k offset from the base address.
118 	 */
119 	orig = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL);
120 
121 	/* Test SPI_CS_CONTROL_SW_MODE bit enabling */
122 	value = orig | SPI_CS_CONTROL_SW_MODE;
123 	writel(value, drv_data->ioaddr + offset + SPI_CS_CONTROL);
124 	value = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL);
125 	if (value != (orig | SPI_CS_CONTROL_SW_MODE)) {
126 		offset = 0x800;
127 		goto detection_done;
128 	}
129 
130 	orig = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL);
131 
132 	/* Test SPI_CS_CONTROL_SW_MODE bit disabling */
133 	value = orig & ~SPI_CS_CONTROL_SW_MODE;
134 	writel(value, drv_data->ioaddr + offset + SPI_CS_CONTROL);
135 	value = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL);
136 	if (value != (orig & ~SPI_CS_CONTROL_SW_MODE)) {
137 		offset = 0x800;
138 		goto detection_done;
139 	}
140 
141 detection_done:
142 	/* Now set the LPSS base */
143 	drv_data->lpss_base = drv_data->ioaddr + offset;
144 
145 	/* Enable software chip select control */
146 	value = SPI_CS_CONTROL_SW_MODE | SPI_CS_CONTROL_CS_HIGH;
147 	__lpss_ssp_write_priv(drv_data, SPI_CS_CONTROL, value);
148 
149 	/* Enable multiblock DMA transfers */
150 	if (drv_data->master_info->enable_dma) {
151 		__lpss_ssp_write_priv(drv_data, SSP_REG, 1);
152 
153 		value = __lpss_ssp_read_priv(drv_data, GENERAL_REG);
154 		value |= GENERAL_REG_RXTO_HOLDOFF_DISABLE;
155 		__lpss_ssp_write_priv(drv_data, GENERAL_REG, value);
156 	}
157 }
158 
159 static void lpss_ssp_cs_control(struct driver_data *drv_data, bool enable)
160 {
161 	u32 value;
162 
163 	if (!is_lpss_ssp(drv_data))
164 		return;
165 
166 	value = __lpss_ssp_read_priv(drv_data, SPI_CS_CONTROL);
167 	if (enable)
168 		value &= ~SPI_CS_CONTROL_CS_HIGH;
169 	else
170 		value |= SPI_CS_CONTROL_CS_HIGH;
171 	__lpss_ssp_write_priv(drv_data, SPI_CS_CONTROL, value);
172 }
173 
174 static void cs_assert(struct driver_data *drv_data)
175 {
176 	struct chip_data *chip = drv_data->cur_chip;
177 
178 	if (drv_data->ssp_type == CE4100_SSP) {
179 		write_SSSR(drv_data->cur_chip->frm, drv_data->ioaddr);
180 		return;
181 	}
182 
183 	if (chip->cs_control) {
184 		chip->cs_control(PXA2XX_CS_ASSERT);
185 		return;
186 	}
187 
188 	if (gpio_is_valid(chip->gpio_cs)) {
189 		gpio_set_value(chip->gpio_cs, chip->gpio_cs_inverted);
190 		return;
191 	}
192 
193 	lpss_ssp_cs_control(drv_data, true);
194 }
195 
196 static void cs_deassert(struct driver_data *drv_data)
197 {
198 	struct chip_data *chip = drv_data->cur_chip;
199 
200 	if (drv_data->ssp_type == CE4100_SSP)
201 		return;
202 
203 	if (chip->cs_control) {
204 		chip->cs_control(PXA2XX_CS_DEASSERT);
205 		return;
206 	}
207 
208 	if (gpio_is_valid(chip->gpio_cs)) {
209 		gpio_set_value(chip->gpio_cs, !chip->gpio_cs_inverted);
210 		return;
211 	}
212 
213 	lpss_ssp_cs_control(drv_data, false);
214 }
215 
216 int pxa2xx_spi_flush(struct driver_data *drv_data)
217 {
218 	unsigned long limit = loops_per_jiffy << 1;
219 
220 	void __iomem *reg = drv_data->ioaddr;
221 
222 	do {
223 		while (read_SSSR(reg) & SSSR_RNE) {
224 			read_SSDR(reg);
225 		}
226 	} while ((read_SSSR(reg) & SSSR_BSY) && --limit);
227 	write_SSSR_CS(drv_data, SSSR_ROR);
228 
229 	return limit;
230 }
231 
232 static int null_writer(struct driver_data *drv_data)
233 {
234 	void __iomem *reg = drv_data->ioaddr;
235 	u8 n_bytes = drv_data->n_bytes;
236 
237 	if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK)
238 		|| (drv_data->tx == drv_data->tx_end))
239 		return 0;
240 
241 	write_SSDR(0, reg);
242 	drv_data->tx += n_bytes;
243 
244 	return 1;
245 }
246 
247 static int null_reader(struct driver_data *drv_data)
248 {
249 	void __iomem *reg = drv_data->ioaddr;
250 	u8 n_bytes = drv_data->n_bytes;
251 
252 	while ((read_SSSR(reg) & SSSR_RNE)
253 		&& (drv_data->rx < drv_data->rx_end)) {
254 		read_SSDR(reg);
255 		drv_data->rx += n_bytes;
256 	}
257 
258 	return drv_data->rx == drv_data->rx_end;
259 }
260 
261 static int u8_writer(struct driver_data *drv_data)
262 {
263 	void __iomem *reg = drv_data->ioaddr;
264 
265 	if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK)
266 		|| (drv_data->tx == drv_data->tx_end))
267 		return 0;
268 
269 	write_SSDR(*(u8 *)(drv_data->tx), reg);
270 	++drv_data->tx;
271 
272 	return 1;
273 }
274 
275 static int u8_reader(struct driver_data *drv_data)
276 {
277 	void __iomem *reg = drv_data->ioaddr;
278 
279 	while ((read_SSSR(reg) & SSSR_RNE)
280 		&& (drv_data->rx < drv_data->rx_end)) {
281 		*(u8 *)(drv_data->rx) = read_SSDR(reg);
282 		++drv_data->rx;
283 	}
284 
285 	return drv_data->rx == drv_data->rx_end;
286 }
287 
288 static int u16_writer(struct driver_data *drv_data)
289 {
290 	void __iomem *reg = drv_data->ioaddr;
291 
292 	if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK)
293 		|| (drv_data->tx == drv_data->tx_end))
294 		return 0;
295 
296 	write_SSDR(*(u16 *)(drv_data->tx), reg);
297 	drv_data->tx += 2;
298 
299 	return 1;
300 }
301 
302 static int u16_reader(struct driver_data *drv_data)
303 {
304 	void __iomem *reg = drv_data->ioaddr;
305 
306 	while ((read_SSSR(reg) & SSSR_RNE)
307 		&& (drv_data->rx < drv_data->rx_end)) {
308 		*(u16 *)(drv_data->rx) = read_SSDR(reg);
309 		drv_data->rx += 2;
310 	}
311 
312 	return drv_data->rx == drv_data->rx_end;
313 }
314 
315 static int u32_writer(struct driver_data *drv_data)
316 {
317 	void __iomem *reg = drv_data->ioaddr;
318 
319 	if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK)
320 		|| (drv_data->tx == drv_data->tx_end))
321 		return 0;
322 
323 	write_SSDR(*(u32 *)(drv_data->tx), reg);
324 	drv_data->tx += 4;
325 
326 	return 1;
327 }
328 
329 static int u32_reader(struct driver_data *drv_data)
330 {
331 	void __iomem *reg = drv_data->ioaddr;
332 
333 	while ((read_SSSR(reg) & SSSR_RNE)
334 		&& (drv_data->rx < drv_data->rx_end)) {
335 		*(u32 *)(drv_data->rx) = read_SSDR(reg);
336 		drv_data->rx += 4;
337 	}
338 
339 	return drv_data->rx == drv_data->rx_end;
340 }
341 
342 void *pxa2xx_spi_next_transfer(struct driver_data *drv_data)
343 {
344 	struct spi_message *msg = drv_data->cur_msg;
345 	struct spi_transfer *trans = drv_data->cur_transfer;
346 
347 	/* Move to next transfer */
348 	if (trans->transfer_list.next != &msg->transfers) {
349 		drv_data->cur_transfer =
350 			list_entry(trans->transfer_list.next,
351 					struct spi_transfer,
352 					transfer_list);
353 		return RUNNING_STATE;
354 	} else
355 		return DONE_STATE;
356 }
357 
358 /* caller already set message->status; dma and pio irqs are blocked */
359 static void giveback(struct driver_data *drv_data)
360 {
361 	struct spi_transfer* last_transfer;
362 	struct spi_message *msg;
363 
364 	msg = drv_data->cur_msg;
365 	drv_data->cur_msg = NULL;
366 	drv_data->cur_transfer = NULL;
367 
368 	last_transfer = list_last_entry(&msg->transfers, struct spi_transfer,
369 					transfer_list);
370 
371 	/* Delay if requested before any change in chip select */
372 	if (last_transfer->delay_usecs)
373 		udelay(last_transfer->delay_usecs);
374 
375 	/* Drop chip select UNLESS cs_change is true or we are returning
376 	 * a message with an error, or next message is for another chip
377 	 */
378 	if (!last_transfer->cs_change)
379 		cs_deassert(drv_data);
380 	else {
381 		struct spi_message *next_msg;
382 
383 		/* Holding of cs was hinted, but we need to make sure
384 		 * the next message is for the same chip.  Don't waste
385 		 * time with the following tests unless this was hinted.
386 		 *
387 		 * We cannot postpone this until pump_messages, because
388 		 * after calling msg->complete (below) the driver that
389 		 * sent the current message could be unloaded, which
390 		 * could invalidate the cs_control() callback...
391 		 */
392 
393 		/* get a pointer to the next message, if any */
394 		next_msg = spi_get_next_queued_message(drv_data->master);
395 
396 		/* see if the next and current messages point
397 		 * to the same chip
398 		 */
399 		if (next_msg && next_msg->spi != msg->spi)
400 			next_msg = NULL;
401 		if (!next_msg || msg->state == ERROR_STATE)
402 			cs_deassert(drv_data);
403 	}
404 
405 	spi_finalize_current_message(drv_data->master);
406 	drv_data->cur_chip = NULL;
407 }
408 
409 static void reset_sccr1(struct driver_data *drv_data)
410 {
411 	void __iomem *reg = drv_data->ioaddr;
412 	struct chip_data *chip = drv_data->cur_chip;
413 	u32 sccr1_reg;
414 
415 	sccr1_reg = read_SSCR1(reg) & ~drv_data->int_cr1;
416 	sccr1_reg &= ~SSCR1_RFT;
417 	sccr1_reg |= chip->threshold;
418 	write_SSCR1(sccr1_reg, reg);
419 }
420 
421 static void int_error_stop(struct driver_data *drv_data, const char* msg)
422 {
423 	void __iomem *reg = drv_data->ioaddr;
424 
425 	/* Stop and reset SSP */
426 	write_SSSR_CS(drv_data, drv_data->clear_sr);
427 	reset_sccr1(drv_data);
428 	if (!pxa25x_ssp_comp(drv_data))
429 		write_SSTO(0, reg);
430 	pxa2xx_spi_flush(drv_data);
431 	write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
432 
433 	dev_err(&drv_data->pdev->dev, "%s\n", msg);
434 
435 	drv_data->cur_msg->state = ERROR_STATE;
436 	tasklet_schedule(&drv_data->pump_transfers);
437 }
438 
439 static void int_transfer_complete(struct driver_data *drv_data)
440 {
441 	void __iomem *reg = drv_data->ioaddr;
442 
443 	/* Stop SSP */
444 	write_SSSR_CS(drv_data, drv_data->clear_sr);
445 	reset_sccr1(drv_data);
446 	if (!pxa25x_ssp_comp(drv_data))
447 		write_SSTO(0, reg);
448 
449 	/* Update total byte transferred return count actual bytes read */
450 	drv_data->cur_msg->actual_length += drv_data->len -
451 				(drv_data->rx_end - drv_data->rx);
452 
453 	/* Transfer delays and chip select release are
454 	 * handled in pump_transfers or giveback
455 	 */
456 
457 	/* Move to next transfer */
458 	drv_data->cur_msg->state = pxa2xx_spi_next_transfer(drv_data);
459 
460 	/* Schedule transfer tasklet */
461 	tasklet_schedule(&drv_data->pump_transfers);
462 }
463 
464 static irqreturn_t interrupt_transfer(struct driver_data *drv_data)
465 {
466 	void __iomem *reg = drv_data->ioaddr;
467 
468 	u32 irq_mask = (read_SSCR1(reg) & SSCR1_TIE) ?
469 			drv_data->mask_sr : drv_data->mask_sr & ~SSSR_TFS;
470 
471 	u32 irq_status = read_SSSR(reg) & irq_mask;
472 
473 	if (irq_status & SSSR_ROR) {
474 		int_error_stop(drv_data, "interrupt_transfer: fifo overrun");
475 		return IRQ_HANDLED;
476 	}
477 
478 	if (irq_status & SSSR_TINT) {
479 		write_SSSR(SSSR_TINT, reg);
480 		if (drv_data->read(drv_data)) {
481 			int_transfer_complete(drv_data);
482 			return IRQ_HANDLED;
483 		}
484 	}
485 
486 	/* Drain rx fifo, Fill tx fifo and prevent overruns */
487 	do {
488 		if (drv_data->read(drv_data)) {
489 			int_transfer_complete(drv_data);
490 			return IRQ_HANDLED;
491 		}
492 	} while (drv_data->write(drv_data));
493 
494 	if (drv_data->read(drv_data)) {
495 		int_transfer_complete(drv_data);
496 		return IRQ_HANDLED;
497 	}
498 
499 	if (drv_data->tx == drv_data->tx_end) {
500 		u32 bytes_left;
501 		u32 sccr1_reg;
502 
503 		sccr1_reg = read_SSCR1(reg);
504 		sccr1_reg &= ~SSCR1_TIE;
505 
506 		/*
507 		 * PXA25x_SSP has no timeout, set up rx threshould for the
508 		 * remaining RX bytes.
509 		 */
510 		if (pxa25x_ssp_comp(drv_data)) {
511 
512 			sccr1_reg &= ~SSCR1_RFT;
513 
514 			bytes_left = drv_data->rx_end - drv_data->rx;
515 			switch (drv_data->n_bytes) {
516 			case 4:
517 				bytes_left >>= 1;
518 			case 2:
519 				bytes_left >>= 1;
520 			}
521 
522 			if (bytes_left > RX_THRESH_DFLT)
523 				bytes_left = RX_THRESH_DFLT;
524 
525 			sccr1_reg |= SSCR1_RxTresh(bytes_left);
526 		}
527 		write_SSCR1(sccr1_reg, reg);
528 	}
529 
530 	/* We did something */
531 	return IRQ_HANDLED;
532 }
533 
534 static irqreturn_t ssp_int(int irq, void *dev_id)
535 {
536 	struct driver_data *drv_data = dev_id;
537 	void __iomem *reg = drv_data->ioaddr;
538 	u32 sccr1_reg;
539 	u32 mask = drv_data->mask_sr;
540 	u32 status;
541 
542 	/*
543 	 * The IRQ might be shared with other peripherals so we must first
544 	 * check that are we RPM suspended or not. If we are we assume that
545 	 * the IRQ was not for us (we shouldn't be RPM suspended when the
546 	 * interrupt is enabled).
547 	 */
548 	if (pm_runtime_suspended(&drv_data->pdev->dev))
549 		return IRQ_NONE;
550 
551 	/*
552 	 * If the device is not yet in RPM suspended state and we get an
553 	 * interrupt that is meant for another device, check if status bits
554 	 * are all set to one. That means that the device is already
555 	 * powered off.
556 	 */
557 	status = read_SSSR(reg);
558 	if (status == ~0)
559 		return IRQ_NONE;
560 
561 	sccr1_reg = read_SSCR1(reg);
562 
563 	/* Ignore possible writes if we don't need to write */
564 	if (!(sccr1_reg & SSCR1_TIE))
565 		mask &= ~SSSR_TFS;
566 
567 	if (!(status & mask))
568 		return IRQ_NONE;
569 
570 	if (!drv_data->cur_msg) {
571 
572 		write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
573 		write_SSCR1(read_SSCR1(reg) & ~drv_data->int_cr1, reg);
574 		if (!pxa25x_ssp_comp(drv_data))
575 			write_SSTO(0, reg);
576 		write_SSSR_CS(drv_data, drv_data->clear_sr);
577 
578 		dev_err(&drv_data->pdev->dev,
579 			"bad message state in interrupt handler\n");
580 
581 		/* Never fail */
582 		return IRQ_HANDLED;
583 	}
584 
585 	return drv_data->transfer_handler(drv_data);
586 }
587 
588 static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate)
589 {
590 	unsigned long ssp_clk = drv_data->max_clk_rate;
591 	const struct ssp_device *ssp = drv_data->ssp;
592 
593 	rate = min_t(int, ssp_clk, rate);
594 
595 	if (ssp->type == PXA25x_SSP || ssp->type == CE4100_SSP)
596 		return ((ssp_clk / (2 * rate) - 1) & 0xff) << 8;
597 	else
598 		return ((ssp_clk / rate - 1) & 0xfff) << 8;
599 }
600 
601 static void pump_transfers(unsigned long data)
602 {
603 	struct driver_data *drv_data = (struct driver_data *)data;
604 	struct spi_message *message = NULL;
605 	struct spi_transfer *transfer = NULL;
606 	struct spi_transfer *previous = NULL;
607 	struct chip_data *chip = NULL;
608 	void __iomem *reg = drv_data->ioaddr;
609 	u32 clk_div = 0;
610 	u8 bits = 0;
611 	u32 speed = 0;
612 	u32 cr0;
613 	u32 cr1;
614 	u32 dma_thresh = drv_data->cur_chip->dma_threshold;
615 	u32 dma_burst = drv_data->cur_chip->dma_burst_size;
616 
617 	/* Get current state information */
618 	message = drv_data->cur_msg;
619 	transfer = drv_data->cur_transfer;
620 	chip = drv_data->cur_chip;
621 
622 	/* Handle for abort */
623 	if (message->state == ERROR_STATE) {
624 		message->status = -EIO;
625 		giveback(drv_data);
626 		return;
627 	}
628 
629 	/* Handle end of message */
630 	if (message->state == DONE_STATE) {
631 		message->status = 0;
632 		giveback(drv_data);
633 		return;
634 	}
635 
636 	/* Delay if requested at end of transfer before CS change */
637 	if (message->state == RUNNING_STATE) {
638 		previous = list_entry(transfer->transfer_list.prev,
639 					struct spi_transfer,
640 					transfer_list);
641 		if (previous->delay_usecs)
642 			udelay(previous->delay_usecs);
643 
644 		/* Drop chip select only if cs_change is requested */
645 		if (previous->cs_change)
646 			cs_deassert(drv_data);
647 	}
648 
649 	/* Check if we can DMA this transfer */
650 	if (!pxa2xx_spi_dma_is_possible(transfer->len) && chip->enable_dma) {
651 
652 		/* reject already-mapped transfers; PIO won't always work */
653 		if (message->is_dma_mapped
654 				|| transfer->rx_dma || transfer->tx_dma) {
655 			dev_err(&drv_data->pdev->dev,
656 				"pump_transfers: mapped transfer length of "
657 				"%u is greater than %d\n",
658 				transfer->len, MAX_DMA_LEN);
659 			message->status = -EINVAL;
660 			giveback(drv_data);
661 			return;
662 		}
663 
664 		/* warn ... we force this to PIO mode */
665 		dev_warn_ratelimited(&message->spi->dev,
666 				     "pump_transfers: DMA disabled for transfer length %ld "
667 				     "greater than %d\n",
668 				     (long)drv_data->len, MAX_DMA_LEN);
669 	}
670 
671 	/* Setup the transfer state based on the type of transfer */
672 	if (pxa2xx_spi_flush(drv_data) == 0) {
673 		dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
674 		message->status = -EIO;
675 		giveback(drv_data);
676 		return;
677 	}
678 	drv_data->n_bytes = chip->n_bytes;
679 	drv_data->tx = (void *)transfer->tx_buf;
680 	drv_data->tx_end = drv_data->tx + transfer->len;
681 	drv_data->rx = transfer->rx_buf;
682 	drv_data->rx_end = drv_data->rx + transfer->len;
683 	drv_data->rx_dma = transfer->rx_dma;
684 	drv_data->tx_dma = transfer->tx_dma;
685 	drv_data->len = transfer->len;
686 	drv_data->write = drv_data->tx ? chip->write : null_writer;
687 	drv_data->read = drv_data->rx ? chip->read : null_reader;
688 
689 	/* Change speed and bit per word on a per transfer */
690 	cr0 = chip->cr0;
691 	if (transfer->speed_hz || transfer->bits_per_word) {
692 
693 		bits = chip->bits_per_word;
694 		speed = chip->speed_hz;
695 
696 		if (transfer->speed_hz)
697 			speed = transfer->speed_hz;
698 
699 		if (transfer->bits_per_word)
700 			bits = transfer->bits_per_word;
701 
702 		clk_div = ssp_get_clk_div(drv_data, speed);
703 
704 		if (bits <= 8) {
705 			drv_data->n_bytes = 1;
706 			drv_data->read = drv_data->read != null_reader ?
707 						u8_reader : null_reader;
708 			drv_data->write = drv_data->write != null_writer ?
709 						u8_writer : null_writer;
710 		} else if (bits <= 16) {
711 			drv_data->n_bytes = 2;
712 			drv_data->read = drv_data->read != null_reader ?
713 						u16_reader : null_reader;
714 			drv_data->write = drv_data->write != null_writer ?
715 						u16_writer : null_writer;
716 		} else if (bits <= 32) {
717 			drv_data->n_bytes = 4;
718 			drv_data->read = drv_data->read != null_reader ?
719 						u32_reader : null_reader;
720 			drv_data->write = drv_data->write != null_writer ?
721 						u32_writer : null_writer;
722 		}
723 		/* if bits/word is changed in dma mode, then must check the
724 		 * thresholds and burst also */
725 		if (chip->enable_dma) {
726 			if (pxa2xx_spi_set_dma_burst_and_threshold(chip,
727 							message->spi,
728 							bits, &dma_burst,
729 							&dma_thresh))
730 				dev_warn_ratelimited(&message->spi->dev,
731 						     "pump_transfers: DMA burst size reduced to match bits_per_word\n");
732 		}
733 
734 		cr0 = clk_div
735 			| SSCR0_Motorola
736 			| SSCR0_DataSize(bits > 16 ? bits - 16 : bits)
737 			| SSCR0_SSE
738 			| (bits > 16 ? SSCR0_EDSS : 0);
739 	}
740 
741 	message->state = RUNNING_STATE;
742 
743 	drv_data->dma_mapped = 0;
744 	if (pxa2xx_spi_dma_is_possible(drv_data->len))
745 		drv_data->dma_mapped = pxa2xx_spi_map_dma_buffers(drv_data);
746 	if (drv_data->dma_mapped) {
747 
748 		/* Ensure we have the correct interrupt handler */
749 		drv_data->transfer_handler = pxa2xx_spi_dma_transfer;
750 
751 		pxa2xx_spi_dma_prepare(drv_data, dma_burst);
752 
753 		/* Clear status and start DMA engine */
754 		cr1 = chip->cr1 | dma_thresh | drv_data->dma_cr1;
755 		write_SSSR(drv_data->clear_sr, reg);
756 
757 		pxa2xx_spi_dma_start(drv_data);
758 	} else {
759 		/* Ensure we have the correct interrupt handler	*/
760 		drv_data->transfer_handler = interrupt_transfer;
761 
762 		/* Clear status  */
763 		cr1 = chip->cr1 | chip->threshold | drv_data->int_cr1;
764 		write_SSSR_CS(drv_data, drv_data->clear_sr);
765 	}
766 
767 	if (is_lpss_ssp(drv_data)) {
768 		if ((read_SSIRF(reg) & 0xff) != chip->lpss_rx_threshold)
769 			write_SSIRF(chip->lpss_rx_threshold, reg);
770 		if ((read_SSITF(reg) & 0xffff) != chip->lpss_tx_threshold)
771 			write_SSITF(chip->lpss_tx_threshold, reg);
772 	}
773 
774 	/* see if we need to reload the config registers */
775 	if ((read_SSCR0(reg) != cr0)
776 		|| (read_SSCR1(reg) & SSCR1_CHANGE_MASK) !=
777 			(cr1 & SSCR1_CHANGE_MASK)) {
778 
779 		/* stop the SSP, and update the other bits */
780 		write_SSCR0(cr0 & ~SSCR0_SSE, reg);
781 		if (!pxa25x_ssp_comp(drv_data))
782 			write_SSTO(chip->timeout, reg);
783 		/* first set CR1 without interrupt and service enables */
784 		write_SSCR1(cr1 & SSCR1_CHANGE_MASK, reg);
785 		/* restart the SSP */
786 		write_SSCR0(cr0, reg);
787 
788 	} else {
789 		if (!pxa25x_ssp_comp(drv_data))
790 			write_SSTO(chip->timeout, reg);
791 	}
792 
793 	cs_assert(drv_data);
794 
795 	/* after chip select, release the data by enabling service
796 	 * requests and interrupts, without changing any mode bits */
797 	write_SSCR1(cr1, reg);
798 }
799 
800 static int pxa2xx_spi_transfer_one_message(struct spi_master *master,
801 					   struct spi_message *msg)
802 {
803 	struct driver_data *drv_data = spi_master_get_devdata(master);
804 
805 	drv_data->cur_msg = msg;
806 	/* Initial message state*/
807 	drv_data->cur_msg->state = START_STATE;
808 	drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
809 						struct spi_transfer,
810 						transfer_list);
811 
812 	/* prepare to setup the SSP, in pump_transfers, using the per
813 	 * chip configuration */
814 	drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
815 
816 	/* Mark as busy and launch transfers */
817 	tasklet_schedule(&drv_data->pump_transfers);
818 	return 0;
819 }
820 
821 static int pxa2xx_spi_unprepare_transfer(struct spi_master *master)
822 {
823 	struct driver_data *drv_data = spi_master_get_devdata(master);
824 
825 	/* Disable the SSP now */
826 	write_SSCR0(read_SSCR0(drv_data->ioaddr) & ~SSCR0_SSE,
827 		    drv_data->ioaddr);
828 
829 	return 0;
830 }
831 
832 static int setup_cs(struct spi_device *spi, struct chip_data *chip,
833 		    struct pxa2xx_spi_chip *chip_info)
834 {
835 	int err = 0;
836 
837 	if (chip == NULL || chip_info == NULL)
838 		return 0;
839 
840 	/* NOTE: setup() can be called multiple times, possibly with
841 	 * different chip_info, release previously requested GPIO
842 	 */
843 	if (gpio_is_valid(chip->gpio_cs))
844 		gpio_free(chip->gpio_cs);
845 
846 	/* If (*cs_control) is provided, ignore GPIO chip select */
847 	if (chip_info->cs_control) {
848 		chip->cs_control = chip_info->cs_control;
849 		return 0;
850 	}
851 
852 	if (gpio_is_valid(chip_info->gpio_cs)) {
853 		err = gpio_request(chip_info->gpio_cs, "SPI_CS");
854 		if (err) {
855 			dev_err(&spi->dev, "failed to request chip select GPIO%d\n",
856 				chip_info->gpio_cs);
857 			return err;
858 		}
859 
860 		chip->gpio_cs = chip_info->gpio_cs;
861 		chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH;
862 
863 		err = gpio_direction_output(chip->gpio_cs,
864 					!chip->gpio_cs_inverted);
865 	}
866 
867 	return err;
868 }
869 
870 static int setup(struct spi_device *spi)
871 {
872 	struct pxa2xx_spi_chip *chip_info = NULL;
873 	struct chip_data *chip;
874 	struct driver_data *drv_data = spi_master_get_devdata(spi->master);
875 	unsigned int clk_div;
876 	uint tx_thres, tx_hi_thres, rx_thres;
877 
878 	if (is_lpss_ssp(drv_data)) {
879 		tx_thres = LPSS_TX_LOTHRESH_DFLT;
880 		tx_hi_thres = LPSS_TX_HITHRESH_DFLT;
881 		rx_thres = LPSS_RX_THRESH_DFLT;
882 	} else {
883 		tx_thres = TX_THRESH_DFLT;
884 		tx_hi_thres = 0;
885 		rx_thres = RX_THRESH_DFLT;
886 	}
887 
888 	/* Only alloc on first setup */
889 	chip = spi_get_ctldata(spi);
890 	if (!chip) {
891 		chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
892 		if (!chip)
893 			return -ENOMEM;
894 
895 		if (drv_data->ssp_type == CE4100_SSP) {
896 			if (spi->chip_select > 4) {
897 				dev_err(&spi->dev,
898 					"failed setup: cs number must not be > 4.\n");
899 				kfree(chip);
900 				return -EINVAL;
901 			}
902 
903 			chip->frm = spi->chip_select;
904 		} else
905 			chip->gpio_cs = -1;
906 		chip->enable_dma = 0;
907 		chip->timeout = TIMOUT_DFLT;
908 	}
909 
910 	/* protocol drivers may change the chip settings, so...
911 	 * if chip_info exists, use it */
912 	chip_info = spi->controller_data;
913 
914 	/* chip_info isn't always needed */
915 	chip->cr1 = 0;
916 	if (chip_info) {
917 		if (chip_info->timeout)
918 			chip->timeout = chip_info->timeout;
919 		if (chip_info->tx_threshold)
920 			tx_thres = chip_info->tx_threshold;
921 		if (chip_info->tx_hi_threshold)
922 			tx_hi_thres = chip_info->tx_hi_threshold;
923 		if (chip_info->rx_threshold)
924 			rx_thres = chip_info->rx_threshold;
925 		chip->enable_dma = drv_data->master_info->enable_dma;
926 		chip->dma_threshold = 0;
927 		if (chip_info->enable_loopback)
928 			chip->cr1 = SSCR1_LBM;
929 	} else if (ACPI_HANDLE(&spi->dev)) {
930 		/*
931 		 * Slave devices enumerated from ACPI namespace don't
932 		 * usually have chip_info but we still might want to use
933 		 * DMA with them.
934 		 */
935 		chip->enable_dma = drv_data->master_info->enable_dma;
936 	}
937 
938 	chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) |
939 			(SSCR1_TxTresh(tx_thres) & SSCR1_TFT);
940 
941 	chip->lpss_rx_threshold = SSIRF_RxThresh(rx_thres);
942 	chip->lpss_tx_threshold = SSITF_TxLoThresh(tx_thres)
943 				| SSITF_TxHiThresh(tx_hi_thres);
944 
945 	/* set dma burst and threshold outside of chip_info path so that if
946 	 * chip_info goes away after setting chip->enable_dma, the
947 	 * burst and threshold can still respond to changes in bits_per_word */
948 	if (chip->enable_dma) {
949 		/* set up legal burst and threshold for dma */
950 		if (pxa2xx_spi_set_dma_burst_and_threshold(chip, spi,
951 						spi->bits_per_word,
952 						&chip->dma_burst_size,
953 						&chip->dma_threshold)) {
954 			dev_warn(&spi->dev,
955 				 "in setup: DMA burst size reduced to match bits_per_word\n");
956 		}
957 	}
958 
959 	clk_div = ssp_get_clk_div(drv_data, spi->max_speed_hz);
960 	chip->speed_hz = spi->max_speed_hz;
961 
962 	chip->cr0 = clk_div
963 			| SSCR0_Motorola
964 			| SSCR0_DataSize(spi->bits_per_word > 16 ?
965 				spi->bits_per_word - 16 : spi->bits_per_word)
966 			| SSCR0_SSE
967 			| (spi->bits_per_word > 16 ? SSCR0_EDSS : 0);
968 	chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH);
969 	chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0)
970 			| (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0);
971 
972 	if (spi->mode & SPI_LOOP)
973 		chip->cr1 |= SSCR1_LBM;
974 
975 	/* NOTE:  PXA25x_SSP _could_ use external clocking ... */
976 	if (!pxa25x_ssp_comp(drv_data))
977 		dev_dbg(&spi->dev, "%ld Hz actual, %s\n",
978 			drv_data->max_clk_rate
979 				/ (1 + ((chip->cr0 & SSCR0_SCR(0xfff)) >> 8)),
980 			chip->enable_dma ? "DMA" : "PIO");
981 	else
982 		dev_dbg(&spi->dev, "%ld Hz actual, %s\n",
983 			drv_data->max_clk_rate / 2
984 				/ (1 + ((chip->cr0 & SSCR0_SCR(0x0ff)) >> 8)),
985 			chip->enable_dma ? "DMA" : "PIO");
986 
987 	if (spi->bits_per_word <= 8) {
988 		chip->n_bytes = 1;
989 		chip->read = u8_reader;
990 		chip->write = u8_writer;
991 	} else if (spi->bits_per_word <= 16) {
992 		chip->n_bytes = 2;
993 		chip->read = u16_reader;
994 		chip->write = u16_writer;
995 	} else if (spi->bits_per_word <= 32) {
996 		chip->cr0 |= SSCR0_EDSS;
997 		chip->n_bytes = 4;
998 		chip->read = u32_reader;
999 		chip->write = u32_writer;
1000 	}
1001 	chip->bits_per_word = spi->bits_per_word;
1002 
1003 	spi_set_ctldata(spi, chip);
1004 
1005 	if (drv_data->ssp_type == CE4100_SSP)
1006 		return 0;
1007 
1008 	return setup_cs(spi, chip, chip_info);
1009 }
1010 
1011 static void cleanup(struct spi_device *spi)
1012 {
1013 	struct chip_data *chip = spi_get_ctldata(spi);
1014 	struct driver_data *drv_data = spi_master_get_devdata(spi->master);
1015 
1016 	if (!chip)
1017 		return;
1018 
1019 	if (drv_data->ssp_type != CE4100_SSP && gpio_is_valid(chip->gpio_cs))
1020 		gpio_free(chip->gpio_cs);
1021 
1022 	kfree(chip);
1023 }
1024 
1025 #ifdef CONFIG_ACPI
1026 static struct pxa2xx_spi_master *
1027 pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
1028 {
1029 	struct pxa2xx_spi_master *pdata;
1030 	struct acpi_device *adev;
1031 	struct ssp_device *ssp;
1032 	struct resource *res;
1033 	int devid;
1034 
1035 	if (!ACPI_HANDLE(&pdev->dev) ||
1036 	    acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
1037 		return NULL;
1038 
1039 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
1040 	if (!pdata)
1041 		return NULL;
1042 
1043 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1044 	if (!res)
1045 		return NULL;
1046 
1047 	ssp = &pdata->ssp;
1048 
1049 	ssp->phys_base = res->start;
1050 	ssp->mmio_base = devm_ioremap_resource(&pdev->dev, res);
1051 	if (IS_ERR(ssp->mmio_base))
1052 		return NULL;
1053 
1054 	ssp->clk = devm_clk_get(&pdev->dev, NULL);
1055 	ssp->irq = platform_get_irq(pdev, 0);
1056 	ssp->type = LPSS_SSP;
1057 	ssp->pdev = pdev;
1058 
1059 	ssp->port_id = -1;
1060 	if (adev->pnp.unique_id && !kstrtoint(adev->pnp.unique_id, 0, &devid))
1061 		ssp->port_id = devid;
1062 
1063 	pdata->num_chipselect = 1;
1064 	pdata->enable_dma = true;
1065 
1066 	return pdata;
1067 }
1068 
1069 static struct acpi_device_id pxa2xx_spi_acpi_match[] = {
1070 	{ "INT33C0", 0 },
1071 	{ "INT33C1", 0 },
1072 	{ "INT3430", 0 },
1073 	{ "INT3431", 0 },
1074 	{ "80860F0E", 0 },
1075 	{ "8086228E", 0 },
1076 	{ },
1077 };
1078 MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match);
1079 #else
1080 static inline struct pxa2xx_spi_master *
1081 pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
1082 {
1083 	return NULL;
1084 }
1085 #endif
1086 
1087 static int pxa2xx_spi_probe(struct platform_device *pdev)
1088 {
1089 	struct device *dev = &pdev->dev;
1090 	struct pxa2xx_spi_master *platform_info;
1091 	struct spi_master *master;
1092 	struct driver_data *drv_data;
1093 	struct ssp_device *ssp;
1094 	int status;
1095 
1096 	platform_info = dev_get_platdata(dev);
1097 	if (!platform_info) {
1098 		platform_info = pxa2xx_spi_acpi_get_pdata(pdev);
1099 		if (!platform_info) {
1100 			dev_err(&pdev->dev, "missing platform data\n");
1101 			return -ENODEV;
1102 		}
1103 	}
1104 
1105 	ssp = pxa_ssp_request(pdev->id, pdev->name);
1106 	if (!ssp)
1107 		ssp = &platform_info->ssp;
1108 
1109 	if (!ssp->mmio_base) {
1110 		dev_err(&pdev->dev, "failed to get ssp\n");
1111 		return -ENODEV;
1112 	}
1113 
1114 	/* Allocate master with space for drv_data and null dma buffer */
1115 	master = spi_alloc_master(dev, sizeof(struct driver_data) + 16);
1116 	if (!master) {
1117 		dev_err(&pdev->dev, "cannot alloc spi_master\n");
1118 		pxa_ssp_free(ssp);
1119 		return -ENOMEM;
1120 	}
1121 	drv_data = spi_master_get_devdata(master);
1122 	drv_data->master = master;
1123 	drv_data->master_info = platform_info;
1124 	drv_data->pdev = pdev;
1125 	drv_data->ssp = ssp;
1126 
1127 	master->dev.parent = &pdev->dev;
1128 	master->dev.of_node = pdev->dev.of_node;
1129 	/* the spi->mode bits understood by this driver: */
1130 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
1131 
1132 	master->bus_num = ssp->port_id;
1133 	master->num_chipselect = platform_info->num_chipselect;
1134 	master->dma_alignment = DMA_ALIGNMENT;
1135 	master->cleanup = cleanup;
1136 	master->setup = setup;
1137 	master->transfer_one_message = pxa2xx_spi_transfer_one_message;
1138 	master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer;
1139 	master->auto_runtime_pm = true;
1140 
1141 	drv_data->ssp_type = ssp->type;
1142 	drv_data->null_dma_buf = (u32 *)PTR_ALIGN(&drv_data[1], DMA_ALIGNMENT);
1143 
1144 	drv_data->ioaddr = ssp->mmio_base;
1145 	drv_data->ssdr_physical = ssp->phys_base + SSDR;
1146 	if (pxa25x_ssp_comp(drv_data)) {
1147 		master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
1148 		drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE;
1149 		drv_data->dma_cr1 = 0;
1150 		drv_data->clear_sr = SSSR_ROR;
1151 		drv_data->mask_sr = SSSR_RFS | SSSR_TFS | SSSR_ROR;
1152 	} else {
1153 		master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1154 		drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE | SSCR1_TINTE;
1155 		drv_data->dma_cr1 = DEFAULT_DMA_CR1;
1156 		drv_data->clear_sr = SSSR_ROR | SSSR_TINT;
1157 		drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS | SSSR_ROR;
1158 	}
1159 
1160 	status = request_irq(ssp->irq, ssp_int, IRQF_SHARED, dev_name(dev),
1161 			drv_data);
1162 	if (status < 0) {
1163 		dev_err(&pdev->dev, "cannot get IRQ %d\n", ssp->irq);
1164 		goto out_error_master_alloc;
1165 	}
1166 
1167 	/* Setup DMA if requested */
1168 	drv_data->tx_channel = -1;
1169 	drv_data->rx_channel = -1;
1170 	if (platform_info->enable_dma) {
1171 		status = pxa2xx_spi_dma_setup(drv_data);
1172 		if (status) {
1173 			dev_dbg(dev, "no DMA channels available, using PIO\n");
1174 			platform_info->enable_dma = false;
1175 		}
1176 	}
1177 
1178 	/* Enable SOC clock */
1179 	clk_prepare_enable(ssp->clk);
1180 
1181 	drv_data->max_clk_rate = clk_get_rate(ssp->clk);
1182 
1183 	/* Load default SSP configuration */
1184 	write_SSCR0(0, drv_data->ioaddr);
1185 	write_SSCR1(SSCR1_RxTresh(RX_THRESH_DFLT) |
1186 				SSCR1_TxTresh(TX_THRESH_DFLT),
1187 				drv_data->ioaddr);
1188 	write_SSCR0(SSCR0_SCR(2)
1189 			| SSCR0_Motorola
1190 			| SSCR0_DataSize(8),
1191 			drv_data->ioaddr);
1192 	if (!pxa25x_ssp_comp(drv_data))
1193 		write_SSTO(0, drv_data->ioaddr);
1194 	write_SSPSP(0, drv_data->ioaddr);
1195 
1196 	lpss_ssp_setup(drv_data);
1197 
1198 	tasklet_init(&drv_data->pump_transfers, pump_transfers,
1199 		     (unsigned long)drv_data);
1200 
1201 	pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
1202 	pm_runtime_use_autosuspend(&pdev->dev);
1203 	pm_runtime_set_active(&pdev->dev);
1204 	pm_runtime_enable(&pdev->dev);
1205 
1206 	/* Register with the SPI framework */
1207 	platform_set_drvdata(pdev, drv_data);
1208 	status = devm_spi_register_master(&pdev->dev, master);
1209 	if (status != 0) {
1210 		dev_err(&pdev->dev, "problem registering spi master\n");
1211 		goto out_error_clock_enabled;
1212 	}
1213 
1214 	return status;
1215 
1216 out_error_clock_enabled:
1217 	clk_disable_unprepare(ssp->clk);
1218 	pxa2xx_spi_dma_release(drv_data);
1219 	free_irq(ssp->irq, drv_data);
1220 
1221 out_error_master_alloc:
1222 	spi_master_put(master);
1223 	pxa_ssp_free(ssp);
1224 	return status;
1225 }
1226 
1227 static int pxa2xx_spi_remove(struct platform_device *pdev)
1228 {
1229 	struct driver_data *drv_data = platform_get_drvdata(pdev);
1230 	struct ssp_device *ssp;
1231 
1232 	if (!drv_data)
1233 		return 0;
1234 	ssp = drv_data->ssp;
1235 
1236 	pm_runtime_get_sync(&pdev->dev);
1237 
1238 	/* Disable the SSP at the peripheral and SOC level */
1239 	write_SSCR0(0, drv_data->ioaddr);
1240 	clk_disable_unprepare(ssp->clk);
1241 
1242 	/* Release DMA */
1243 	if (drv_data->master_info->enable_dma)
1244 		pxa2xx_spi_dma_release(drv_data);
1245 
1246 	pm_runtime_put_noidle(&pdev->dev);
1247 	pm_runtime_disable(&pdev->dev);
1248 
1249 	/* Release IRQ */
1250 	free_irq(ssp->irq, drv_data);
1251 
1252 	/* Release SSP */
1253 	pxa_ssp_free(ssp);
1254 
1255 	return 0;
1256 }
1257 
1258 static void pxa2xx_spi_shutdown(struct platform_device *pdev)
1259 {
1260 	int status = 0;
1261 
1262 	if ((status = pxa2xx_spi_remove(pdev)) != 0)
1263 		dev_err(&pdev->dev, "shutdown failed with %d\n", status);
1264 }
1265 
1266 #ifdef CONFIG_PM_SLEEP
1267 static int pxa2xx_spi_suspend(struct device *dev)
1268 {
1269 	struct driver_data *drv_data = dev_get_drvdata(dev);
1270 	struct ssp_device *ssp = drv_data->ssp;
1271 	int status = 0;
1272 
1273 	status = spi_master_suspend(drv_data->master);
1274 	if (status != 0)
1275 		return status;
1276 	write_SSCR0(0, drv_data->ioaddr);
1277 	clk_disable_unprepare(ssp->clk);
1278 
1279 	return 0;
1280 }
1281 
1282 static int pxa2xx_spi_resume(struct device *dev)
1283 {
1284 	struct driver_data *drv_data = dev_get_drvdata(dev);
1285 	struct ssp_device *ssp = drv_data->ssp;
1286 	int status = 0;
1287 
1288 	pxa2xx_spi_dma_resume(drv_data);
1289 
1290 	/* Enable the SSP clock */
1291 	clk_prepare_enable(ssp->clk);
1292 
1293 	/* Restore LPSS private register bits */
1294 	lpss_ssp_setup(drv_data);
1295 
1296 	/* Start the queue running */
1297 	status = spi_master_resume(drv_data->master);
1298 	if (status != 0) {
1299 		dev_err(dev, "problem starting queue (%d)\n", status);
1300 		return status;
1301 	}
1302 
1303 	return 0;
1304 }
1305 #endif
1306 
1307 #ifdef CONFIG_PM_RUNTIME
1308 static int pxa2xx_spi_runtime_suspend(struct device *dev)
1309 {
1310 	struct driver_data *drv_data = dev_get_drvdata(dev);
1311 
1312 	clk_disable_unprepare(drv_data->ssp->clk);
1313 	return 0;
1314 }
1315 
1316 static int pxa2xx_spi_runtime_resume(struct device *dev)
1317 {
1318 	struct driver_data *drv_data = dev_get_drvdata(dev);
1319 
1320 	clk_prepare_enable(drv_data->ssp->clk);
1321 	return 0;
1322 }
1323 #endif
1324 
1325 static const struct dev_pm_ops pxa2xx_spi_pm_ops = {
1326 	SET_SYSTEM_SLEEP_PM_OPS(pxa2xx_spi_suspend, pxa2xx_spi_resume)
1327 	SET_RUNTIME_PM_OPS(pxa2xx_spi_runtime_suspend,
1328 			   pxa2xx_spi_runtime_resume, NULL)
1329 };
1330 
1331 static struct platform_driver driver = {
1332 	.driver = {
1333 		.name	= "pxa2xx-spi",
1334 		.owner	= THIS_MODULE,
1335 		.pm	= &pxa2xx_spi_pm_ops,
1336 		.acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match),
1337 	},
1338 	.probe = pxa2xx_spi_probe,
1339 	.remove = pxa2xx_spi_remove,
1340 	.shutdown = pxa2xx_spi_shutdown,
1341 };
1342 
1343 static int __init pxa2xx_spi_init(void)
1344 {
1345 	return platform_driver_register(&driver);
1346 }
1347 subsys_initcall(pxa2xx_spi_init);
1348 
1349 static void __exit pxa2xx_spi_exit(void)
1350 {
1351 	platform_driver_unregister(&driver);
1352 }
1353 module_exit(pxa2xx_spi_exit);
1354