xref: /openbmc/linux/drivers/spi/spi-pxa2xx.c (revision bc000245)
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/workqueue.h>
31 #include <linux/delay.h>
32 #include <linux/gpio.h>
33 #include <linux/slab.h>
34 #include <linux/clk.h>
35 #include <linux/pm_runtime.h>
36 #include <linux/acpi.h>
37 
38 #include <asm/io.h>
39 #include <asm/irq.h>
40 #include <asm/delay.h>
41 
42 #include "spi-pxa2xx.h"
43 
44 MODULE_AUTHOR("Stephen Street");
45 MODULE_DESCRIPTION("PXA2xx SSP SPI Controller");
46 MODULE_LICENSE("GPL");
47 MODULE_ALIAS("platform:pxa2xx-spi");
48 
49 #define MAX_BUSES 3
50 
51 #define TIMOUT_DFLT		1000
52 
53 /*
54  * for testing SSCR1 changes that require SSP restart, basically
55  * everything except the service and interrupt enables, the pxa270 developer
56  * manual says only SSCR1_SCFR, SSCR1_SPH, SSCR1_SPO need to be in this
57  * list, but the PXA255 dev man says all bits without really meaning the
58  * service and interrupt enables
59  */
60 #define SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_SCFR \
61 				| SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \
62 				| SSCR1_SFRMDIR | SSCR1_RWOT | SSCR1_TRAIL \
63 				| SSCR1_IFS | SSCR1_STRF | SSCR1_EFWR \
64 				| SSCR1_RFT | SSCR1_TFT | SSCR1_MWDS \
65 				| SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
66 
67 #define LPSS_RX_THRESH_DFLT	64
68 #define LPSS_TX_LOTHRESH_DFLT	160
69 #define LPSS_TX_HITHRESH_DFLT	224
70 
71 /* Offset from drv_data->lpss_base */
72 #define GENERAL_REG		0x08
73 #define GENERAL_REG_RXTO_HOLDOFF_DISABLE BIT(24)
74 #define SSP_REG			0x0c
75 #define SPI_CS_CONTROL		0x18
76 #define SPI_CS_CONTROL_SW_MODE	BIT(0)
77 #define SPI_CS_CONTROL_CS_HIGH	BIT(1)
78 
79 static bool is_lpss_ssp(const struct driver_data *drv_data)
80 {
81 	return drv_data->ssp_type == LPSS_SSP;
82 }
83 
84 /*
85  * Read and write LPSS SSP private registers. Caller must first check that
86  * is_lpss_ssp() returns true before these can be called.
87  */
88 static u32 __lpss_ssp_read_priv(struct driver_data *drv_data, unsigned offset)
89 {
90 	WARN_ON(!drv_data->lpss_base);
91 	return readl(drv_data->lpss_base + offset);
92 }
93 
94 static void __lpss_ssp_write_priv(struct driver_data *drv_data,
95 				  unsigned offset, u32 value)
96 {
97 	WARN_ON(!drv_data->lpss_base);
98 	writel(value, drv_data->lpss_base + offset);
99 }
100 
101 /*
102  * lpss_ssp_setup - perform LPSS SSP specific setup
103  * @drv_data: pointer to the driver private data
104  *
105  * Perform LPSS SSP specific setup. This function must be called first if
106  * one is going to use LPSS SSP private registers.
107  */
108 static void lpss_ssp_setup(struct driver_data *drv_data)
109 {
110 	unsigned offset = 0x400;
111 	u32 value, orig;
112 
113 	if (!is_lpss_ssp(drv_data))
114 		return;
115 
116 	/*
117 	 * Perform auto-detection of the LPSS SSP private registers. They
118 	 * can be either at 1k or 2k offset from the base address.
119 	 */
120 	orig = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL);
121 
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 	value &= ~SPI_CS_CONTROL_SW_MODE;
131 	writel(value, drv_data->ioaddr + offset + SPI_CS_CONTROL);
132 	value = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL);
133 	if (value != orig) {
134 		offset = 0x800;
135 		goto detection_done;
136 	}
137 
138 detection_done:
139 	/* Now set the LPSS base */
140 	drv_data->lpss_base = drv_data->ioaddr + offset;
141 
142 	/* Enable software chip select control */
143 	value = SPI_CS_CONTROL_SW_MODE | SPI_CS_CONTROL_CS_HIGH;
144 	__lpss_ssp_write_priv(drv_data, SPI_CS_CONTROL, value);
145 
146 	/* Enable multiblock DMA transfers */
147 	if (drv_data->master_info->enable_dma) {
148 		__lpss_ssp_write_priv(drv_data, SSP_REG, 1);
149 
150 		value = __lpss_ssp_read_priv(drv_data, GENERAL_REG);
151 		value |= GENERAL_REG_RXTO_HOLDOFF_DISABLE;
152 		__lpss_ssp_write_priv(drv_data, GENERAL_REG, value);
153 	}
154 }
155 
156 static void lpss_ssp_cs_control(struct driver_data *drv_data, bool enable)
157 {
158 	u32 value;
159 
160 	if (!is_lpss_ssp(drv_data))
161 		return;
162 
163 	value = __lpss_ssp_read_priv(drv_data, SPI_CS_CONTROL);
164 	if (enable)
165 		value &= ~SPI_CS_CONTROL_CS_HIGH;
166 	else
167 		value |= SPI_CS_CONTROL_CS_HIGH;
168 	__lpss_ssp_write_priv(drv_data, SPI_CS_CONTROL, value);
169 }
170 
171 static void cs_assert(struct driver_data *drv_data)
172 {
173 	struct chip_data *chip = drv_data->cur_chip;
174 
175 	if (drv_data->ssp_type == CE4100_SSP) {
176 		write_SSSR(drv_data->cur_chip->frm, drv_data->ioaddr);
177 		return;
178 	}
179 
180 	if (chip->cs_control) {
181 		chip->cs_control(PXA2XX_CS_ASSERT);
182 		return;
183 	}
184 
185 	if (gpio_is_valid(chip->gpio_cs)) {
186 		gpio_set_value(chip->gpio_cs, chip->gpio_cs_inverted);
187 		return;
188 	}
189 
190 	lpss_ssp_cs_control(drv_data, true);
191 }
192 
193 static void cs_deassert(struct driver_data *drv_data)
194 {
195 	struct chip_data *chip = drv_data->cur_chip;
196 
197 	if (drv_data->ssp_type == CE4100_SSP)
198 		return;
199 
200 	if (chip->cs_control) {
201 		chip->cs_control(PXA2XX_CS_DEASSERT);
202 		return;
203 	}
204 
205 	if (gpio_is_valid(chip->gpio_cs)) {
206 		gpio_set_value(chip->gpio_cs, !chip->gpio_cs_inverted);
207 		return;
208 	}
209 
210 	lpss_ssp_cs_control(drv_data, false);
211 }
212 
213 int pxa2xx_spi_flush(struct driver_data *drv_data)
214 {
215 	unsigned long limit = loops_per_jiffy << 1;
216 
217 	void __iomem *reg = drv_data->ioaddr;
218 
219 	do {
220 		while (read_SSSR(reg) & SSSR_RNE) {
221 			read_SSDR(reg);
222 		}
223 	} while ((read_SSSR(reg) & SSSR_BSY) && --limit);
224 	write_SSSR_CS(drv_data, SSSR_ROR);
225 
226 	return limit;
227 }
228 
229 static int null_writer(struct driver_data *drv_data)
230 {
231 	void __iomem *reg = drv_data->ioaddr;
232 	u8 n_bytes = drv_data->n_bytes;
233 
234 	if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK)
235 		|| (drv_data->tx == drv_data->tx_end))
236 		return 0;
237 
238 	write_SSDR(0, reg);
239 	drv_data->tx += n_bytes;
240 
241 	return 1;
242 }
243 
244 static int null_reader(struct driver_data *drv_data)
245 {
246 	void __iomem *reg = drv_data->ioaddr;
247 	u8 n_bytes = drv_data->n_bytes;
248 
249 	while ((read_SSSR(reg) & SSSR_RNE)
250 		&& (drv_data->rx < drv_data->rx_end)) {
251 		read_SSDR(reg);
252 		drv_data->rx += n_bytes;
253 	}
254 
255 	return drv_data->rx == drv_data->rx_end;
256 }
257 
258 static int u8_writer(struct driver_data *drv_data)
259 {
260 	void __iomem *reg = drv_data->ioaddr;
261 
262 	if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK)
263 		|| (drv_data->tx == drv_data->tx_end))
264 		return 0;
265 
266 	write_SSDR(*(u8 *)(drv_data->tx), reg);
267 	++drv_data->tx;
268 
269 	return 1;
270 }
271 
272 static int u8_reader(struct driver_data *drv_data)
273 {
274 	void __iomem *reg = drv_data->ioaddr;
275 
276 	while ((read_SSSR(reg) & SSSR_RNE)
277 		&& (drv_data->rx < drv_data->rx_end)) {
278 		*(u8 *)(drv_data->rx) = read_SSDR(reg);
279 		++drv_data->rx;
280 	}
281 
282 	return drv_data->rx == drv_data->rx_end;
283 }
284 
285 static int u16_writer(struct driver_data *drv_data)
286 {
287 	void __iomem *reg = drv_data->ioaddr;
288 
289 	if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK)
290 		|| (drv_data->tx == drv_data->tx_end))
291 		return 0;
292 
293 	write_SSDR(*(u16 *)(drv_data->tx), reg);
294 	drv_data->tx += 2;
295 
296 	return 1;
297 }
298 
299 static int u16_reader(struct driver_data *drv_data)
300 {
301 	void __iomem *reg = drv_data->ioaddr;
302 
303 	while ((read_SSSR(reg) & SSSR_RNE)
304 		&& (drv_data->rx < drv_data->rx_end)) {
305 		*(u16 *)(drv_data->rx) = read_SSDR(reg);
306 		drv_data->rx += 2;
307 	}
308 
309 	return drv_data->rx == drv_data->rx_end;
310 }
311 
312 static int u32_writer(struct driver_data *drv_data)
313 {
314 	void __iomem *reg = drv_data->ioaddr;
315 
316 	if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK)
317 		|| (drv_data->tx == drv_data->tx_end))
318 		return 0;
319 
320 	write_SSDR(*(u32 *)(drv_data->tx), reg);
321 	drv_data->tx += 4;
322 
323 	return 1;
324 }
325 
326 static int u32_reader(struct driver_data *drv_data)
327 {
328 	void __iomem *reg = drv_data->ioaddr;
329 
330 	while ((read_SSSR(reg) & SSSR_RNE)
331 		&& (drv_data->rx < drv_data->rx_end)) {
332 		*(u32 *)(drv_data->rx) = read_SSDR(reg);
333 		drv_data->rx += 4;
334 	}
335 
336 	return drv_data->rx == drv_data->rx_end;
337 }
338 
339 void *pxa2xx_spi_next_transfer(struct driver_data *drv_data)
340 {
341 	struct spi_message *msg = drv_data->cur_msg;
342 	struct spi_transfer *trans = drv_data->cur_transfer;
343 
344 	/* Move to next transfer */
345 	if (trans->transfer_list.next != &msg->transfers) {
346 		drv_data->cur_transfer =
347 			list_entry(trans->transfer_list.next,
348 					struct spi_transfer,
349 					transfer_list);
350 		return RUNNING_STATE;
351 	} else
352 		return DONE_STATE;
353 }
354 
355 /* caller already set message->status; dma and pio irqs are blocked */
356 static void giveback(struct driver_data *drv_data)
357 {
358 	struct spi_transfer* last_transfer;
359 	struct spi_message *msg;
360 
361 	msg = drv_data->cur_msg;
362 	drv_data->cur_msg = NULL;
363 	drv_data->cur_transfer = NULL;
364 
365 	last_transfer = list_entry(msg->transfers.prev,
366 					struct spi_transfer,
367 					transfer_list);
368 
369 	/* Delay if requested before any change in chip select */
370 	if (last_transfer->delay_usecs)
371 		udelay(last_transfer->delay_usecs);
372 
373 	/* Drop chip select UNLESS cs_change is true or we are returning
374 	 * a message with an error, or next message is for another chip
375 	 */
376 	if (!last_transfer->cs_change)
377 		cs_deassert(drv_data);
378 	else {
379 		struct spi_message *next_msg;
380 
381 		/* Holding of cs was hinted, but we need to make sure
382 		 * the next message is for the same chip.  Don't waste
383 		 * time with the following tests unless this was hinted.
384 		 *
385 		 * We cannot postpone this until pump_messages, because
386 		 * after calling msg->complete (below) the driver that
387 		 * sent the current message could be unloaded, which
388 		 * could invalidate the cs_control() callback...
389 		 */
390 
391 		/* get a pointer to the next message, if any */
392 		next_msg = spi_get_next_queued_message(drv_data->master);
393 
394 		/* see if the next and current messages point
395 		 * to the same chip
396 		 */
397 		if (next_msg && next_msg->spi != msg->spi)
398 			next_msg = NULL;
399 		if (!next_msg || msg->state == ERROR_STATE)
400 			cs_deassert(drv_data);
401 	}
402 
403 	spi_finalize_current_message(drv_data->master);
404 	drv_data->cur_chip = NULL;
405 }
406 
407 static void reset_sccr1(struct driver_data *drv_data)
408 {
409 	void __iomem *reg = drv_data->ioaddr;
410 	struct chip_data *chip = drv_data->cur_chip;
411 	u32 sccr1_reg;
412 
413 	sccr1_reg = read_SSCR1(reg) & ~drv_data->int_cr1;
414 	sccr1_reg &= ~SSCR1_RFT;
415 	sccr1_reg |= chip->threshold;
416 	write_SSCR1(sccr1_reg, reg);
417 }
418 
419 static void int_error_stop(struct driver_data *drv_data, const char* msg)
420 {
421 	void __iomem *reg = drv_data->ioaddr;
422 
423 	/* Stop and reset SSP */
424 	write_SSSR_CS(drv_data, drv_data->clear_sr);
425 	reset_sccr1(drv_data);
426 	if (!pxa25x_ssp_comp(drv_data))
427 		write_SSTO(0, reg);
428 	pxa2xx_spi_flush(drv_data);
429 	write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
430 
431 	dev_err(&drv_data->pdev->dev, "%s\n", msg);
432 
433 	drv_data->cur_msg->state = ERROR_STATE;
434 	tasklet_schedule(&drv_data->pump_transfers);
435 }
436 
437 static void int_transfer_complete(struct driver_data *drv_data)
438 {
439 	void __iomem *reg = drv_data->ioaddr;
440 
441 	/* Stop SSP */
442 	write_SSSR_CS(drv_data, drv_data->clear_sr);
443 	reset_sccr1(drv_data);
444 	if (!pxa25x_ssp_comp(drv_data))
445 		write_SSTO(0, reg);
446 
447 	/* Update total byte transferred return count actual bytes read */
448 	drv_data->cur_msg->actual_length += drv_data->len -
449 				(drv_data->rx_end - drv_data->rx);
450 
451 	/* Transfer delays and chip select release are
452 	 * handled in pump_transfers or giveback
453 	 */
454 
455 	/* Move to next transfer */
456 	drv_data->cur_msg->state = pxa2xx_spi_next_transfer(drv_data);
457 
458 	/* Schedule transfer tasklet */
459 	tasklet_schedule(&drv_data->pump_transfers);
460 }
461 
462 static irqreturn_t interrupt_transfer(struct driver_data *drv_data)
463 {
464 	void __iomem *reg = drv_data->ioaddr;
465 
466 	u32 irq_mask = (read_SSCR1(reg) & SSCR1_TIE) ?
467 			drv_data->mask_sr : drv_data->mask_sr & ~SSSR_TFS;
468 
469 	u32 irq_status = read_SSSR(reg) & irq_mask;
470 
471 	if (irq_status & SSSR_ROR) {
472 		int_error_stop(drv_data, "interrupt_transfer: fifo overrun");
473 		return IRQ_HANDLED;
474 	}
475 
476 	if (irq_status & SSSR_TINT) {
477 		write_SSSR(SSSR_TINT, reg);
478 		if (drv_data->read(drv_data)) {
479 			int_transfer_complete(drv_data);
480 			return IRQ_HANDLED;
481 		}
482 	}
483 
484 	/* Drain rx fifo, Fill tx fifo and prevent overruns */
485 	do {
486 		if (drv_data->read(drv_data)) {
487 			int_transfer_complete(drv_data);
488 			return IRQ_HANDLED;
489 		}
490 	} while (drv_data->write(drv_data));
491 
492 	if (drv_data->read(drv_data)) {
493 		int_transfer_complete(drv_data);
494 		return IRQ_HANDLED;
495 	}
496 
497 	if (drv_data->tx == drv_data->tx_end) {
498 		u32 bytes_left;
499 		u32 sccr1_reg;
500 
501 		sccr1_reg = read_SSCR1(reg);
502 		sccr1_reg &= ~SSCR1_TIE;
503 
504 		/*
505 		 * PXA25x_SSP has no timeout, set up rx threshould for the
506 		 * remaining RX bytes.
507 		 */
508 		if (pxa25x_ssp_comp(drv_data)) {
509 
510 			sccr1_reg &= ~SSCR1_RFT;
511 
512 			bytes_left = drv_data->rx_end - drv_data->rx;
513 			switch (drv_data->n_bytes) {
514 			case 4:
515 				bytes_left >>= 1;
516 			case 2:
517 				bytes_left >>= 1;
518 			}
519 
520 			if (bytes_left > RX_THRESH_DFLT)
521 				bytes_left = RX_THRESH_DFLT;
522 
523 			sccr1_reg |= SSCR1_RxTresh(bytes_left);
524 		}
525 		write_SSCR1(sccr1_reg, reg);
526 	}
527 
528 	/* We did something */
529 	return IRQ_HANDLED;
530 }
531 
532 static irqreturn_t ssp_int(int irq, void *dev_id)
533 {
534 	struct driver_data *drv_data = dev_id;
535 	void __iomem *reg = drv_data->ioaddr;
536 	u32 sccr1_reg;
537 	u32 mask = drv_data->mask_sr;
538 	u32 status;
539 
540 	/*
541 	 * The IRQ might be shared with other peripherals so we must first
542 	 * check that are we RPM suspended or not. If we are we assume that
543 	 * the IRQ was not for us (we shouldn't be RPM suspended when the
544 	 * interrupt is enabled).
545 	 */
546 	if (pm_runtime_suspended(&drv_data->pdev->dev))
547 		return IRQ_NONE;
548 
549 	/*
550 	 * If the device is not yet in RPM suspended state and we get an
551 	 * interrupt that is meant for another device, check if status bits
552 	 * are all set to one. That means that the device is already
553 	 * powered off.
554 	 */
555 	status = read_SSSR(reg);
556 	if (status == ~0)
557 		return IRQ_NONE;
558 
559 	sccr1_reg = read_SSCR1(reg);
560 
561 	/* Ignore possible writes if we don't need to write */
562 	if (!(sccr1_reg & SSCR1_TIE))
563 		mask &= ~SSSR_TFS;
564 
565 	if (!(status & mask))
566 		return IRQ_NONE;
567 
568 	if (!drv_data->cur_msg) {
569 
570 		write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
571 		write_SSCR1(read_SSCR1(reg) & ~drv_data->int_cr1, reg);
572 		if (!pxa25x_ssp_comp(drv_data))
573 			write_SSTO(0, reg);
574 		write_SSSR_CS(drv_data, drv_data->clear_sr);
575 
576 		dev_err(&drv_data->pdev->dev,
577 			"bad message state in interrupt handler\n");
578 
579 		/* Never fail */
580 		return IRQ_HANDLED;
581 	}
582 
583 	return drv_data->transfer_handler(drv_data);
584 }
585 
586 static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate)
587 {
588 	unsigned long ssp_clk = drv_data->max_clk_rate;
589 	const struct ssp_device *ssp = drv_data->ssp;
590 
591 	rate = min_t(int, ssp_clk, rate);
592 
593 	if (ssp->type == PXA25x_SSP || ssp->type == CE4100_SSP)
594 		return ((ssp_clk / (2 * rate) - 1) & 0xff) << 8;
595 	else
596 		return ((ssp_clk / rate - 1) & 0xfff) << 8;
597 }
598 
599 static void pump_transfers(unsigned long data)
600 {
601 	struct driver_data *drv_data = (struct driver_data *)data;
602 	struct spi_message *message = NULL;
603 	struct spi_transfer *transfer = NULL;
604 	struct spi_transfer *previous = NULL;
605 	struct chip_data *chip = NULL;
606 	void __iomem *reg = drv_data->ioaddr;
607 	u32 clk_div = 0;
608 	u8 bits = 0;
609 	u32 speed = 0;
610 	u32 cr0;
611 	u32 cr1;
612 	u32 dma_thresh = drv_data->cur_chip->dma_threshold;
613 	u32 dma_burst = drv_data->cur_chip->dma_burst_size;
614 
615 	/* Get current state information */
616 	message = drv_data->cur_msg;
617 	transfer = drv_data->cur_transfer;
618 	chip = drv_data->cur_chip;
619 
620 	/* Handle for abort */
621 	if (message->state == ERROR_STATE) {
622 		message->status = -EIO;
623 		giveback(drv_data);
624 		return;
625 	}
626 
627 	/* Handle end of message */
628 	if (message->state == DONE_STATE) {
629 		message->status = 0;
630 		giveback(drv_data);
631 		return;
632 	}
633 
634 	/* Delay if requested at end of transfer before CS change */
635 	if (message->state == RUNNING_STATE) {
636 		previous = list_entry(transfer->transfer_list.prev,
637 					struct spi_transfer,
638 					transfer_list);
639 		if (previous->delay_usecs)
640 			udelay(previous->delay_usecs);
641 
642 		/* Drop chip select only if cs_change is requested */
643 		if (previous->cs_change)
644 			cs_deassert(drv_data);
645 	}
646 
647 	/* Check if we can DMA this transfer */
648 	if (!pxa2xx_spi_dma_is_possible(transfer->len) && chip->enable_dma) {
649 
650 		/* reject already-mapped transfers; PIO won't always work */
651 		if (message->is_dma_mapped
652 				|| transfer->rx_dma || transfer->tx_dma) {
653 			dev_err(&drv_data->pdev->dev,
654 				"pump_transfers: mapped transfer length of "
655 				"%u is greater than %d\n",
656 				transfer->len, MAX_DMA_LEN);
657 			message->status = -EINVAL;
658 			giveback(drv_data);
659 			return;
660 		}
661 
662 		/* warn ... we force this to PIO mode */
663 		dev_warn_ratelimited(&message->spi->dev,
664 				     "pump_transfers: DMA disabled for transfer length %ld "
665 				     "greater than %d\n",
666 				     (long)drv_data->len, MAX_DMA_LEN);
667 	}
668 
669 	/* Setup the transfer state based on the type of transfer */
670 	if (pxa2xx_spi_flush(drv_data) == 0) {
671 		dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
672 		message->status = -EIO;
673 		giveback(drv_data);
674 		return;
675 	}
676 	drv_data->n_bytes = chip->n_bytes;
677 	drv_data->tx = (void *)transfer->tx_buf;
678 	drv_data->tx_end = drv_data->tx + transfer->len;
679 	drv_data->rx = transfer->rx_buf;
680 	drv_data->rx_end = drv_data->rx + transfer->len;
681 	drv_data->rx_dma = transfer->rx_dma;
682 	drv_data->tx_dma = transfer->tx_dma;
683 	drv_data->len = transfer->len;
684 	drv_data->write = drv_data->tx ? chip->write : null_writer;
685 	drv_data->read = drv_data->rx ? chip->read : null_reader;
686 
687 	/* Change speed and bit per word on a per transfer */
688 	cr0 = chip->cr0;
689 	if (transfer->speed_hz || transfer->bits_per_word) {
690 
691 		bits = chip->bits_per_word;
692 		speed = chip->speed_hz;
693 
694 		if (transfer->speed_hz)
695 			speed = transfer->speed_hz;
696 
697 		if (transfer->bits_per_word)
698 			bits = transfer->bits_per_word;
699 
700 		clk_div = ssp_get_clk_div(drv_data, speed);
701 
702 		if (bits <= 8) {
703 			drv_data->n_bytes = 1;
704 			drv_data->read = drv_data->read != null_reader ?
705 						u8_reader : null_reader;
706 			drv_data->write = drv_data->write != null_writer ?
707 						u8_writer : null_writer;
708 		} else if (bits <= 16) {
709 			drv_data->n_bytes = 2;
710 			drv_data->read = drv_data->read != null_reader ?
711 						u16_reader : null_reader;
712 			drv_data->write = drv_data->write != null_writer ?
713 						u16_writer : null_writer;
714 		} else if (bits <= 32) {
715 			drv_data->n_bytes = 4;
716 			drv_data->read = drv_data->read != null_reader ?
717 						u32_reader : null_reader;
718 			drv_data->write = drv_data->write != null_writer ?
719 						u32_writer : null_writer;
720 		}
721 		/* if bits/word is changed in dma mode, then must check the
722 		 * thresholds and burst also */
723 		if (chip->enable_dma) {
724 			if (pxa2xx_spi_set_dma_burst_and_threshold(chip,
725 							message->spi,
726 							bits, &dma_burst,
727 							&dma_thresh))
728 				dev_warn_ratelimited(&message->spi->dev,
729 						     "pump_transfers: DMA burst size reduced to match bits_per_word\n");
730 		}
731 
732 		cr0 = clk_div
733 			| SSCR0_Motorola
734 			| SSCR0_DataSize(bits > 16 ? bits - 16 : bits)
735 			| SSCR0_SSE
736 			| (bits > 16 ? SSCR0_EDSS : 0);
737 	}
738 
739 	message->state = RUNNING_STATE;
740 
741 	drv_data->dma_mapped = 0;
742 	if (pxa2xx_spi_dma_is_possible(drv_data->len))
743 		drv_data->dma_mapped = pxa2xx_spi_map_dma_buffers(drv_data);
744 	if (drv_data->dma_mapped) {
745 
746 		/* Ensure we have the correct interrupt handler */
747 		drv_data->transfer_handler = pxa2xx_spi_dma_transfer;
748 
749 		pxa2xx_spi_dma_prepare(drv_data, dma_burst);
750 
751 		/* Clear status and start DMA engine */
752 		cr1 = chip->cr1 | dma_thresh | drv_data->dma_cr1;
753 		write_SSSR(drv_data->clear_sr, reg);
754 
755 		pxa2xx_spi_dma_start(drv_data);
756 	} else {
757 		/* Ensure we have the correct interrupt handler	*/
758 		drv_data->transfer_handler = interrupt_transfer;
759 
760 		/* Clear status  */
761 		cr1 = chip->cr1 | chip->threshold | drv_data->int_cr1;
762 		write_SSSR_CS(drv_data, drv_data->clear_sr);
763 	}
764 
765 	if (is_lpss_ssp(drv_data)) {
766 		if ((read_SSIRF(reg) & 0xff) != chip->lpss_rx_threshold)
767 			write_SSIRF(chip->lpss_rx_threshold, reg);
768 		if ((read_SSITF(reg) & 0xffff) != chip->lpss_tx_threshold)
769 			write_SSITF(chip->lpss_tx_threshold, reg);
770 	}
771 
772 	/* see if we need to reload the config registers */
773 	if ((read_SSCR0(reg) != cr0)
774 		|| (read_SSCR1(reg) & SSCR1_CHANGE_MASK) !=
775 			(cr1 & SSCR1_CHANGE_MASK)) {
776 
777 		/* stop the SSP, and update the other bits */
778 		write_SSCR0(cr0 & ~SSCR0_SSE, reg);
779 		if (!pxa25x_ssp_comp(drv_data))
780 			write_SSTO(chip->timeout, reg);
781 		/* first set CR1 without interrupt and service enables */
782 		write_SSCR1(cr1 & SSCR1_CHANGE_MASK, reg);
783 		/* restart the SSP */
784 		write_SSCR0(cr0, reg);
785 
786 	} else {
787 		if (!pxa25x_ssp_comp(drv_data))
788 			write_SSTO(chip->timeout, reg);
789 	}
790 
791 	cs_assert(drv_data);
792 
793 	/* after chip select, release the data by enabling service
794 	 * requests and interrupts, without changing any mode bits */
795 	write_SSCR1(cr1, reg);
796 }
797 
798 static int pxa2xx_spi_transfer_one_message(struct spi_master *master,
799 					   struct spi_message *msg)
800 {
801 	struct driver_data *drv_data = spi_master_get_devdata(master);
802 
803 	drv_data->cur_msg = msg;
804 	/* Initial message state*/
805 	drv_data->cur_msg->state = START_STATE;
806 	drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
807 						struct spi_transfer,
808 						transfer_list);
809 
810 	/* prepare to setup the SSP, in pump_transfers, using the per
811 	 * chip configuration */
812 	drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
813 
814 	/* Mark as busy and launch transfers */
815 	tasklet_schedule(&drv_data->pump_transfers);
816 	return 0;
817 }
818 
819 static int pxa2xx_spi_unprepare_transfer(struct spi_master *master)
820 {
821 	struct driver_data *drv_data = spi_master_get_devdata(master);
822 
823 	/* Disable the SSP now */
824 	write_SSCR0(read_SSCR0(drv_data->ioaddr) & ~SSCR0_SSE,
825 		    drv_data->ioaddr);
826 
827 	return 0;
828 }
829 
830 static int setup_cs(struct spi_device *spi, struct chip_data *chip,
831 		    struct pxa2xx_spi_chip *chip_info)
832 {
833 	int err = 0;
834 
835 	if (chip == NULL || chip_info == NULL)
836 		return 0;
837 
838 	/* NOTE: setup() can be called multiple times, possibly with
839 	 * different chip_info, release previously requested GPIO
840 	 */
841 	if (gpio_is_valid(chip->gpio_cs))
842 		gpio_free(chip->gpio_cs);
843 
844 	/* If (*cs_control) is provided, ignore GPIO chip select */
845 	if (chip_info->cs_control) {
846 		chip->cs_control = chip_info->cs_control;
847 		return 0;
848 	}
849 
850 	if (gpio_is_valid(chip_info->gpio_cs)) {
851 		err = gpio_request(chip_info->gpio_cs, "SPI_CS");
852 		if (err) {
853 			dev_err(&spi->dev, "failed to request chip select GPIO%d\n",
854 				chip_info->gpio_cs);
855 			return err;
856 		}
857 
858 		chip->gpio_cs = chip_info->gpio_cs;
859 		chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH;
860 
861 		err = gpio_direction_output(chip->gpio_cs,
862 					!chip->gpio_cs_inverted);
863 	}
864 
865 	return err;
866 }
867 
868 static int setup(struct spi_device *spi)
869 {
870 	struct pxa2xx_spi_chip *chip_info = NULL;
871 	struct chip_data *chip;
872 	struct driver_data *drv_data = spi_master_get_devdata(spi->master);
873 	unsigned int clk_div;
874 	uint tx_thres, tx_hi_thres, rx_thres;
875 
876 	if (is_lpss_ssp(drv_data)) {
877 		tx_thres = LPSS_TX_LOTHRESH_DFLT;
878 		tx_hi_thres = LPSS_TX_HITHRESH_DFLT;
879 		rx_thres = LPSS_RX_THRESH_DFLT;
880 	} else {
881 		tx_thres = TX_THRESH_DFLT;
882 		tx_hi_thres = 0;
883 		rx_thres = RX_THRESH_DFLT;
884 	}
885 
886 	/* Only alloc on first setup */
887 	chip = spi_get_ctldata(spi);
888 	if (!chip) {
889 		chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
890 		if (!chip) {
891 			dev_err(&spi->dev,
892 				"failed setup: can't allocate chip data\n");
893 			return -ENOMEM;
894 		}
895 
896 		if (drv_data->ssp_type == CE4100_SSP) {
897 			if (spi->chip_select > 4) {
898 				dev_err(&spi->dev,
899 					"failed setup: cs number must not be > 4.\n");
900 				kfree(chip);
901 				return -EINVAL;
902 			}
903 
904 			chip->frm = spi->chip_select;
905 		} else
906 			chip->gpio_cs = -1;
907 		chip->enable_dma = 0;
908 		chip->timeout = TIMOUT_DFLT;
909 	}
910 
911 	/* protocol drivers may change the chip settings, so...
912 	 * if chip_info exists, use it */
913 	chip_info = spi->controller_data;
914 
915 	/* chip_info isn't always needed */
916 	chip->cr1 = 0;
917 	if (chip_info) {
918 		if (chip_info->timeout)
919 			chip->timeout = chip_info->timeout;
920 		if (chip_info->tx_threshold)
921 			tx_thres = chip_info->tx_threshold;
922 		if (chip_info->tx_hi_threshold)
923 			tx_hi_thres = chip_info->tx_hi_threshold;
924 		if (chip_info->rx_threshold)
925 			rx_thres = chip_info->rx_threshold;
926 		chip->enable_dma = drv_data->master_info->enable_dma;
927 		chip->dma_threshold = 0;
928 		if (chip_info->enable_loopback)
929 			chip->cr1 = SSCR1_LBM;
930 	} else if (ACPI_HANDLE(&spi->dev)) {
931 		/*
932 		 * Slave devices enumerated from ACPI namespace don't
933 		 * usually have chip_info but we still might want to use
934 		 * DMA with them.
935 		 */
936 		chip->enable_dma = drv_data->master_info->enable_dma;
937 	}
938 
939 	chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) |
940 			(SSCR1_TxTresh(tx_thres) & SSCR1_TFT);
941 
942 	chip->lpss_rx_threshold = SSIRF_RxThresh(rx_thres);
943 	chip->lpss_tx_threshold = SSITF_TxLoThresh(tx_thres)
944 				| SSITF_TxHiThresh(tx_hi_thres);
945 
946 	/* set dma burst and threshold outside of chip_info path so that if
947 	 * chip_info goes away after setting chip->enable_dma, the
948 	 * burst and threshold can still respond to changes in bits_per_word */
949 	if (chip->enable_dma) {
950 		/* set up legal burst and threshold for dma */
951 		if (pxa2xx_spi_set_dma_burst_and_threshold(chip, spi,
952 						spi->bits_per_word,
953 						&chip->dma_burst_size,
954 						&chip->dma_threshold)) {
955 			dev_warn(&spi->dev,
956 				 "in setup: DMA burst size reduced to match bits_per_word\n");
957 		}
958 	}
959 
960 	clk_div = ssp_get_clk_div(drv_data, spi->max_speed_hz);
961 	chip->speed_hz = spi->max_speed_hz;
962 
963 	chip->cr0 = clk_div
964 			| SSCR0_Motorola
965 			| SSCR0_DataSize(spi->bits_per_word > 16 ?
966 				spi->bits_per_word - 16 : spi->bits_per_word)
967 			| SSCR0_SSE
968 			| (spi->bits_per_word > 16 ? SSCR0_EDSS : 0);
969 	chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH);
970 	chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0)
971 			| (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0);
972 
973 	if (spi->mode & SPI_LOOP)
974 		chip->cr1 |= SSCR1_LBM;
975 
976 	/* NOTE:  PXA25x_SSP _could_ use external clocking ... */
977 	if (!pxa25x_ssp_comp(drv_data))
978 		dev_dbg(&spi->dev, "%ld Hz actual, %s\n",
979 			drv_data->max_clk_rate
980 				/ (1 + ((chip->cr0 & SSCR0_SCR(0xfff)) >> 8)),
981 			chip->enable_dma ? "DMA" : "PIO");
982 	else
983 		dev_dbg(&spi->dev, "%ld Hz actual, %s\n",
984 			drv_data->max_clk_rate / 2
985 				/ (1 + ((chip->cr0 & SSCR0_SCR(0x0ff)) >> 8)),
986 			chip->enable_dma ? "DMA" : "PIO");
987 
988 	if (spi->bits_per_word <= 8) {
989 		chip->n_bytes = 1;
990 		chip->read = u8_reader;
991 		chip->write = u8_writer;
992 	} else if (spi->bits_per_word <= 16) {
993 		chip->n_bytes = 2;
994 		chip->read = u16_reader;
995 		chip->write = u16_writer;
996 	} else if (spi->bits_per_word <= 32) {
997 		chip->cr0 |= SSCR0_EDSS;
998 		chip->n_bytes = 4;
999 		chip->read = u32_reader;
1000 		chip->write = u32_writer;
1001 	}
1002 	chip->bits_per_word = spi->bits_per_word;
1003 
1004 	spi_set_ctldata(spi, chip);
1005 
1006 	if (drv_data->ssp_type == CE4100_SSP)
1007 		return 0;
1008 
1009 	return setup_cs(spi, chip, chip_info);
1010 }
1011 
1012 static void cleanup(struct spi_device *spi)
1013 {
1014 	struct chip_data *chip = spi_get_ctldata(spi);
1015 	struct driver_data *drv_data = spi_master_get_devdata(spi->master);
1016 
1017 	if (!chip)
1018 		return;
1019 
1020 	if (drv_data->ssp_type != CE4100_SSP && gpio_is_valid(chip->gpio_cs))
1021 		gpio_free(chip->gpio_cs);
1022 
1023 	kfree(chip);
1024 }
1025 
1026 #ifdef CONFIG_ACPI
1027 static struct pxa2xx_spi_master *
1028 pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
1029 {
1030 	struct pxa2xx_spi_master *pdata;
1031 	struct acpi_device *adev;
1032 	struct ssp_device *ssp;
1033 	struct resource *res;
1034 	int devid;
1035 
1036 	if (!ACPI_HANDLE(&pdev->dev) ||
1037 	    acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
1038 		return NULL;
1039 
1040 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
1041 	if (!pdata) {
1042 		dev_err(&pdev->dev,
1043 			"failed to allocate memory for platform data\n");
1044 		return NULL;
1045 	}
1046 
1047 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1048 	if (!res)
1049 		return NULL;
1050 
1051 	ssp = &pdata->ssp;
1052 
1053 	ssp->phys_base = res->start;
1054 	ssp->mmio_base = devm_ioremap_resource(&pdev->dev, res);
1055 	if (IS_ERR(ssp->mmio_base))
1056 		return NULL;
1057 
1058 	ssp->clk = devm_clk_get(&pdev->dev, NULL);
1059 	ssp->irq = platform_get_irq(pdev, 0);
1060 	ssp->type = LPSS_SSP;
1061 	ssp->pdev = pdev;
1062 
1063 	ssp->port_id = -1;
1064 	if (adev->pnp.unique_id && !kstrtoint(adev->pnp.unique_id, 0, &devid))
1065 		ssp->port_id = devid;
1066 
1067 	pdata->num_chipselect = 1;
1068 	pdata->enable_dma = true;
1069 
1070 	return pdata;
1071 }
1072 
1073 static struct acpi_device_id pxa2xx_spi_acpi_match[] = {
1074 	{ "INT33C0", 0 },
1075 	{ "INT33C1", 0 },
1076 	{ "INT3430", 0 },
1077 	{ "INT3431", 0 },
1078 	{ "80860F0E", 0 },
1079 	{ },
1080 };
1081 MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match);
1082 #else
1083 static inline struct pxa2xx_spi_master *
1084 pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
1085 {
1086 	return NULL;
1087 }
1088 #endif
1089 
1090 static int pxa2xx_spi_probe(struct platform_device *pdev)
1091 {
1092 	struct device *dev = &pdev->dev;
1093 	struct pxa2xx_spi_master *platform_info;
1094 	struct spi_master *master;
1095 	struct driver_data *drv_data;
1096 	struct ssp_device *ssp;
1097 	int status;
1098 
1099 	platform_info = dev_get_platdata(dev);
1100 	if (!platform_info) {
1101 		platform_info = pxa2xx_spi_acpi_get_pdata(pdev);
1102 		if (!platform_info) {
1103 			dev_err(&pdev->dev, "missing platform data\n");
1104 			return -ENODEV;
1105 		}
1106 	}
1107 
1108 	ssp = pxa_ssp_request(pdev->id, pdev->name);
1109 	if (!ssp)
1110 		ssp = &platform_info->ssp;
1111 
1112 	if (!ssp->mmio_base) {
1113 		dev_err(&pdev->dev, "failed to get ssp\n");
1114 		return -ENODEV;
1115 	}
1116 
1117 	/* Allocate master with space for drv_data and null dma buffer */
1118 	master = spi_alloc_master(dev, sizeof(struct driver_data) + 16);
1119 	if (!master) {
1120 		dev_err(&pdev->dev, "cannot alloc spi_master\n");
1121 		pxa_ssp_free(ssp);
1122 		return -ENOMEM;
1123 	}
1124 	drv_data = spi_master_get_devdata(master);
1125 	drv_data->master = master;
1126 	drv_data->master_info = platform_info;
1127 	drv_data->pdev = pdev;
1128 	drv_data->ssp = ssp;
1129 
1130 	master->dev.parent = &pdev->dev;
1131 	master->dev.of_node = pdev->dev.of_node;
1132 	/* the spi->mode bits understood by this driver: */
1133 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
1134 
1135 	master->bus_num = ssp->port_id;
1136 	master->num_chipselect = platform_info->num_chipselect;
1137 	master->dma_alignment = DMA_ALIGNMENT;
1138 	master->cleanup = cleanup;
1139 	master->setup = setup;
1140 	master->transfer_one_message = pxa2xx_spi_transfer_one_message;
1141 	master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer;
1142 	master->auto_runtime_pm = true;
1143 
1144 	drv_data->ssp_type = ssp->type;
1145 	drv_data->null_dma_buf = (u32 *)PTR_ALIGN(&drv_data[1], DMA_ALIGNMENT);
1146 
1147 	drv_data->ioaddr = ssp->mmio_base;
1148 	drv_data->ssdr_physical = ssp->phys_base + SSDR;
1149 	if (pxa25x_ssp_comp(drv_data)) {
1150 		master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
1151 		drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE;
1152 		drv_data->dma_cr1 = 0;
1153 		drv_data->clear_sr = SSSR_ROR;
1154 		drv_data->mask_sr = SSSR_RFS | SSSR_TFS | SSSR_ROR;
1155 	} else {
1156 		master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1157 		drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE | SSCR1_TINTE;
1158 		drv_data->dma_cr1 = DEFAULT_DMA_CR1;
1159 		drv_data->clear_sr = SSSR_ROR | SSSR_TINT;
1160 		drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS | SSSR_ROR;
1161 	}
1162 
1163 	status = request_irq(ssp->irq, ssp_int, IRQF_SHARED, dev_name(dev),
1164 			drv_data);
1165 	if (status < 0) {
1166 		dev_err(&pdev->dev, "cannot get IRQ %d\n", ssp->irq);
1167 		goto out_error_master_alloc;
1168 	}
1169 
1170 	/* Setup DMA if requested */
1171 	drv_data->tx_channel = -1;
1172 	drv_data->rx_channel = -1;
1173 	if (platform_info->enable_dma) {
1174 		status = pxa2xx_spi_dma_setup(drv_data);
1175 		if (status) {
1176 			dev_dbg(dev, "no DMA channels available, using PIO\n");
1177 			platform_info->enable_dma = false;
1178 		}
1179 	}
1180 
1181 	/* Enable SOC clock */
1182 	clk_prepare_enable(ssp->clk);
1183 
1184 	drv_data->max_clk_rate = clk_get_rate(ssp->clk);
1185 
1186 	/* Load default SSP configuration */
1187 	write_SSCR0(0, drv_data->ioaddr);
1188 	write_SSCR1(SSCR1_RxTresh(RX_THRESH_DFLT) |
1189 				SSCR1_TxTresh(TX_THRESH_DFLT),
1190 				drv_data->ioaddr);
1191 	write_SSCR0(SSCR0_SCR(2)
1192 			| SSCR0_Motorola
1193 			| SSCR0_DataSize(8),
1194 			drv_data->ioaddr);
1195 	if (!pxa25x_ssp_comp(drv_data))
1196 		write_SSTO(0, drv_data->ioaddr);
1197 	write_SSPSP(0, drv_data->ioaddr);
1198 
1199 	lpss_ssp_setup(drv_data);
1200 
1201 	tasklet_init(&drv_data->pump_transfers, pump_transfers,
1202 		     (unsigned long)drv_data);
1203 
1204 	/* Register with the SPI framework */
1205 	platform_set_drvdata(pdev, drv_data);
1206 	status = devm_spi_register_master(&pdev->dev, master);
1207 	if (status != 0) {
1208 		dev_err(&pdev->dev, "problem registering spi master\n");
1209 		goto out_error_clock_enabled;
1210 	}
1211 
1212 	pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
1213 	pm_runtime_use_autosuspend(&pdev->dev);
1214 	pm_runtime_set_active(&pdev->dev);
1215 	pm_runtime_enable(&pdev->dev);
1216 
1217 	return status;
1218 
1219 out_error_clock_enabled:
1220 	clk_disable_unprepare(ssp->clk);
1221 	pxa2xx_spi_dma_release(drv_data);
1222 	free_irq(ssp->irq, drv_data);
1223 
1224 out_error_master_alloc:
1225 	spi_master_put(master);
1226 	pxa_ssp_free(ssp);
1227 	return status;
1228 }
1229 
1230 static int pxa2xx_spi_remove(struct platform_device *pdev)
1231 {
1232 	struct driver_data *drv_data = platform_get_drvdata(pdev);
1233 	struct ssp_device *ssp;
1234 
1235 	if (!drv_data)
1236 		return 0;
1237 	ssp = drv_data->ssp;
1238 
1239 	pm_runtime_get_sync(&pdev->dev);
1240 
1241 	/* Disable the SSP at the peripheral and SOC level */
1242 	write_SSCR0(0, drv_data->ioaddr);
1243 	clk_disable_unprepare(ssp->clk);
1244 
1245 	/* Release DMA */
1246 	if (drv_data->master_info->enable_dma)
1247 		pxa2xx_spi_dma_release(drv_data);
1248 
1249 	pm_runtime_put_noidle(&pdev->dev);
1250 	pm_runtime_disable(&pdev->dev);
1251 
1252 	/* Release IRQ */
1253 	free_irq(ssp->irq, drv_data);
1254 
1255 	/* Release SSP */
1256 	pxa_ssp_free(ssp);
1257 
1258 	return 0;
1259 }
1260 
1261 static void pxa2xx_spi_shutdown(struct platform_device *pdev)
1262 {
1263 	int status = 0;
1264 
1265 	if ((status = pxa2xx_spi_remove(pdev)) != 0)
1266 		dev_err(&pdev->dev, "shutdown failed with %d\n", status);
1267 }
1268 
1269 #ifdef CONFIG_PM
1270 static int pxa2xx_spi_suspend(struct device *dev)
1271 {
1272 	struct driver_data *drv_data = dev_get_drvdata(dev);
1273 	struct ssp_device *ssp = drv_data->ssp;
1274 	int status = 0;
1275 
1276 	status = spi_master_suspend(drv_data->master);
1277 	if (status != 0)
1278 		return status;
1279 	write_SSCR0(0, drv_data->ioaddr);
1280 	clk_disable_unprepare(ssp->clk);
1281 
1282 	return 0;
1283 }
1284 
1285 static int pxa2xx_spi_resume(struct device *dev)
1286 {
1287 	struct driver_data *drv_data = dev_get_drvdata(dev);
1288 	struct ssp_device *ssp = drv_data->ssp;
1289 	int status = 0;
1290 
1291 	pxa2xx_spi_dma_resume(drv_data);
1292 
1293 	/* Enable the SSP clock */
1294 	clk_prepare_enable(ssp->clk);
1295 
1296 	/* Restore LPSS private register bits */
1297 	lpss_ssp_setup(drv_data);
1298 
1299 	/* Start the queue running */
1300 	status = spi_master_resume(drv_data->master);
1301 	if (status != 0) {
1302 		dev_err(dev, "problem starting queue (%d)\n", status);
1303 		return status;
1304 	}
1305 
1306 	return 0;
1307 }
1308 #endif
1309 
1310 #ifdef CONFIG_PM_RUNTIME
1311 static int pxa2xx_spi_runtime_suspend(struct device *dev)
1312 {
1313 	struct driver_data *drv_data = dev_get_drvdata(dev);
1314 
1315 	clk_disable_unprepare(drv_data->ssp->clk);
1316 	return 0;
1317 }
1318 
1319 static int pxa2xx_spi_runtime_resume(struct device *dev)
1320 {
1321 	struct driver_data *drv_data = dev_get_drvdata(dev);
1322 
1323 	clk_prepare_enable(drv_data->ssp->clk);
1324 	return 0;
1325 }
1326 #endif
1327 
1328 static const struct dev_pm_ops pxa2xx_spi_pm_ops = {
1329 	SET_SYSTEM_SLEEP_PM_OPS(pxa2xx_spi_suspend, pxa2xx_spi_resume)
1330 	SET_RUNTIME_PM_OPS(pxa2xx_spi_runtime_suspend,
1331 			   pxa2xx_spi_runtime_resume, NULL)
1332 };
1333 
1334 static struct platform_driver driver = {
1335 	.driver = {
1336 		.name	= "pxa2xx-spi",
1337 		.owner	= THIS_MODULE,
1338 		.pm	= &pxa2xx_spi_pm_ops,
1339 		.acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match),
1340 	},
1341 	.probe = pxa2xx_spi_probe,
1342 	.remove = pxa2xx_spi_remove,
1343 	.shutdown = pxa2xx_spi_shutdown,
1344 };
1345 
1346 static int __init pxa2xx_spi_init(void)
1347 {
1348 	return platform_driver_register(&driver);
1349 }
1350 subsys_initcall(pxa2xx_spi_init);
1351 
1352 static void __exit pxa2xx_spi_exit(void)
1353 {
1354 	platform_driver_unregister(&driver);
1355 }
1356 module_exit(pxa2xx_spi_exit);
1357