xref: /linux/drivers/mmc/host/pxamci.c (revision 4b911a9690d72641879ea6d13cce1de31d346d79)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/drivers/mmc/host/pxa.c - PXA MMCI driver
4  *
5  *  Copyright (C) 2003 Russell King, All Rights Reserved.
6  *
7  *  This hardware is really sick:
8  *   - No way to clear interrupts.
9  *   - Have to turn off the clock whenever we touch the device.
10  *   - Doesn't tell you how many data blocks were transferred.
11  *  Yuck!
12  *
13  *	1 and 3 byte data transfers not supported
14  *	max block length up to 1023
15  */
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/ioport.h>
19 #include <linux/platform_device.h>
20 #include <linux/delay.h>
21 #include <linux/interrupt.h>
22 #include <linux/dmaengine.h>
23 #include <linux/dma-mapping.h>
24 #include <linux/clk.h>
25 #include <linux/err.h>
26 #include <linux/mmc/host.h>
27 #include <linux/mmc/slot-gpio.h>
28 #include <linux/io.h>
29 #include <linux/regulator/consumer.h>
30 #include <linux/gpio/consumer.h>
31 #include <linux/gfp.h>
32 #include <linux/of.h>
33 #include <linux/soc/pxa/cpu.h>
34 
35 #include <linux/sizes.h>
36 
37 #include <linux/platform_data/mmc-pxamci.h>
38 
39 #include "pxamci.h"
40 
41 #define DRIVER_NAME	"pxa2xx-mci"
42 
43 #define NR_SG	1
44 #define CLKRT_OFF	(~0)
45 
46 #define mmc_has_26MHz()		(cpu_is_pxa300() || cpu_is_pxa310() \
47 				|| cpu_is_pxa935())
48 
49 struct pxamci_host {
50 	struct mmc_host		*mmc;
51 	spinlock_t		lock;
52 	struct resource		*res;
53 	void __iomem		*base;
54 	struct clk		*clk;
55 	unsigned long		clkrate;
56 	unsigned int		clkrt;
57 	unsigned int		cmdat;
58 	unsigned int		imask;
59 	unsigned int		power_mode;
60 	unsigned long		detect_delay_ms;
61 	bool			use_ro_gpio;
62 	struct gpio_desc	*power;
63 	struct pxamci_platform_data *pdata;
64 
65 	struct mmc_request	*mrq;
66 	struct mmc_command	*cmd;
67 	struct mmc_data		*data;
68 
69 	struct dma_chan		*dma_chan_rx;
70 	struct dma_chan		*dma_chan_tx;
71 	dma_cookie_t		dma_cookie;
72 	unsigned int		dma_len;
73 	unsigned int		dma_dir;
74 };
75 
76 static int pxamci_init_ocr(struct pxamci_host *host)
77 {
78 	struct mmc_host *mmc = host->mmc;
79 	int ret;
80 
81 	ret = mmc_regulator_get_supply(mmc);
82 	if (ret < 0)
83 		return ret;
84 
85 	if (IS_ERR(mmc->supply.vmmc)) {
86 		/* fall-back to platform data */
87 		mmc->ocr_avail = host->pdata ?
88 			host->pdata->ocr_mask :
89 			MMC_VDD_32_33 | MMC_VDD_33_34;
90 	}
91 
92 	return 0;
93 }
94 
95 static inline int pxamci_set_power(struct pxamci_host *host,
96 				    unsigned char power_mode,
97 				    unsigned int vdd)
98 {
99 	struct mmc_host *mmc = host->mmc;
100 	struct regulator *supply = mmc->supply.vmmc;
101 
102 	if (!IS_ERR(supply))
103 		return mmc_regulator_set_ocr(mmc, supply, vdd);
104 
105 	if (host->power) {
106 		bool on = !!((1 << vdd) & host->pdata->ocr_mask);
107 		gpiod_set_value(host->power, on);
108 	}
109 
110 	if (host->pdata && host->pdata->setpower)
111 		return host->pdata->setpower(mmc_dev(host->mmc), vdd);
112 
113 	return 0;
114 }
115 
116 static void pxamci_stop_clock(struct pxamci_host *host)
117 {
118 	if (readl(host->base + MMC_STAT) & STAT_CLK_EN) {
119 		unsigned long timeout = 10000;
120 		unsigned int v;
121 
122 		writel(STOP_CLOCK, host->base + MMC_STRPCL);
123 
124 		do {
125 			v = readl(host->base + MMC_STAT);
126 			if (!(v & STAT_CLK_EN))
127 				break;
128 			udelay(1);
129 		} while (timeout--);
130 
131 		if (v & STAT_CLK_EN)
132 			dev_err(mmc_dev(host->mmc), "unable to stop clock\n");
133 	}
134 }
135 
136 static void pxamci_enable_irq(struct pxamci_host *host, unsigned int mask)
137 {
138 	unsigned long flags;
139 
140 	spin_lock_irqsave(&host->lock, flags);
141 	host->imask &= ~mask;
142 	writel(host->imask, host->base + MMC_I_MASK);
143 	spin_unlock_irqrestore(&host->lock, flags);
144 }
145 
146 static void pxamci_disable_irq(struct pxamci_host *host, unsigned int mask)
147 {
148 	unsigned long flags;
149 
150 	spin_lock_irqsave(&host->lock, flags);
151 	host->imask |= mask;
152 	writel(host->imask, host->base + MMC_I_MASK);
153 	spin_unlock_irqrestore(&host->lock, flags);
154 }
155 
156 static void pxamci_dma_irq(void *param);
157 
158 static void pxamci_setup_data(struct pxamci_host *host, struct mmc_data *data)
159 {
160 	struct dma_async_tx_descriptor *tx;
161 	enum dma_transfer_direction direction;
162 	struct dma_slave_config	config;
163 	struct dma_chan *chan;
164 	unsigned int nob = data->blocks;
165 	unsigned long long clks;
166 	unsigned int timeout;
167 	int ret;
168 
169 	host->data = data;
170 
171 	writel(nob, host->base + MMC_NOB);
172 	writel(data->blksz, host->base + MMC_BLKLEN);
173 
174 	clks = (unsigned long long)data->timeout_ns * host->clkrate;
175 	do_div(clks, 1000000000UL);
176 	timeout = (unsigned int)clks + (data->timeout_clks << host->clkrt);
177 	writel((timeout + 255) / 256, host->base + MMC_RDTO);
178 
179 	memset(&config, 0, sizeof(config));
180 	config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
181 	config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
182 	config.src_addr = host->res->start + MMC_RXFIFO;
183 	config.dst_addr = host->res->start + MMC_TXFIFO;
184 	config.src_maxburst = 32;
185 	config.dst_maxburst = 32;
186 
187 	if (data->flags & MMC_DATA_READ) {
188 		host->dma_dir = DMA_FROM_DEVICE;
189 		direction = DMA_DEV_TO_MEM;
190 		chan = host->dma_chan_rx;
191 	} else {
192 		host->dma_dir = DMA_TO_DEVICE;
193 		direction = DMA_MEM_TO_DEV;
194 		chan = host->dma_chan_tx;
195 	}
196 
197 	config.direction = direction;
198 
199 	ret = dmaengine_slave_config(chan, &config);
200 	if (ret < 0) {
201 		dev_err(mmc_dev(host->mmc), "dma slave config failed\n");
202 		return;
203 	}
204 
205 	host->dma_len = dma_map_sg(chan->device->dev, data->sg, data->sg_len,
206 				   host->dma_dir);
207 
208 	tx = dmaengine_prep_slave_sg(chan, data->sg, host->dma_len, direction,
209 				     DMA_PREP_INTERRUPT);
210 	if (!tx) {
211 		dev_err(mmc_dev(host->mmc), "prep_slave_sg() failed\n");
212 		return;
213 	}
214 
215 	if (!(data->flags & MMC_DATA_READ)) {
216 		tx->callback = pxamci_dma_irq;
217 		tx->callback_param = host;
218 	}
219 
220 	host->dma_cookie = dmaengine_submit(tx);
221 
222 	/*
223 	 * workaround for erratum #91:
224 	 * only start DMA now if we are doing a read,
225 	 * otherwise we wait until CMD/RESP has finished
226 	 * before starting DMA.
227 	 */
228 	if (!cpu_is_pxa27x() || data->flags & MMC_DATA_READ)
229 		dma_async_issue_pending(chan);
230 }
231 
232 static void pxamci_start_cmd(struct pxamci_host *host, struct mmc_command *cmd, unsigned int cmdat)
233 {
234 	WARN_ON(host->cmd != NULL);
235 	host->cmd = cmd;
236 
237 	if (cmd->flags & MMC_RSP_BUSY)
238 		cmdat |= CMDAT_BUSY;
239 
240 #define RSP_TYPE(x)	((x) & ~(MMC_RSP_BUSY|MMC_RSP_OPCODE))
241 	switch (RSP_TYPE(mmc_resp_type(cmd))) {
242 	case RSP_TYPE(MMC_RSP_R1): /* r1, r1b, r6, r7 */
243 		cmdat |= CMDAT_RESP_SHORT;
244 		break;
245 	case RSP_TYPE(MMC_RSP_R3):
246 		cmdat |= CMDAT_RESP_R3;
247 		break;
248 	case RSP_TYPE(MMC_RSP_R2):
249 		cmdat |= CMDAT_RESP_R2;
250 		break;
251 	default:
252 		break;
253 	}
254 
255 	writel(cmd->opcode, host->base + MMC_CMD);
256 	writel(cmd->arg >> 16, host->base + MMC_ARGH);
257 	writel(cmd->arg & 0xffff, host->base + MMC_ARGL);
258 	writel(cmdat, host->base + MMC_CMDAT);
259 	writel(host->clkrt, host->base + MMC_CLKRT);
260 
261 	writel(START_CLOCK, host->base + MMC_STRPCL);
262 
263 	pxamci_enable_irq(host, END_CMD_RES);
264 }
265 
266 static void pxamci_finish_request(struct pxamci_host *host, struct mmc_request *mrq)
267 {
268 	host->mrq = NULL;
269 	host->cmd = NULL;
270 	host->data = NULL;
271 	mmc_request_done(host->mmc, mrq);
272 }
273 
274 static int pxamci_cmd_done(struct pxamci_host *host, unsigned int stat)
275 {
276 	struct mmc_command *cmd = host->cmd;
277 	int i;
278 	u32 v;
279 
280 	if (!cmd)
281 		return 0;
282 
283 	host->cmd = NULL;
284 
285 	/*
286 	 * Did I mention this is Sick.  We always need to
287 	 * discard the upper 8 bits of the first 16-bit word.
288 	 */
289 	v = readl(host->base + MMC_RES) & 0xffff;
290 	for (i = 0; i < 4; i++) {
291 		u32 w1 = readl(host->base + MMC_RES) & 0xffff;
292 		u32 w2 = readl(host->base + MMC_RES) & 0xffff;
293 		cmd->resp[i] = v << 24 | w1 << 8 | w2 >> 8;
294 		v = w2;
295 	}
296 
297 	if (stat & STAT_TIME_OUT_RESPONSE) {
298 		cmd->error = -ETIMEDOUT;
299 	} else if (stat & STAT_RES_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
300 		/*
301 		 * workaround for erratum #42:
302 		 * Intel PXA27x Family Processor Specification Update Rev 001
303 		 * A bogus CRC error can appear if the msb of a 136 bit
304 		 * response is a one.
305 		 */
306 		if (cpu_is_pxa27x() &&
307 		    (cmd->flags & MMC_RSP_136 && cmd->resp[0] & 0x80000000))
308 			pr_debug("ignoring CRC from command %d - *risky*\n", cmd->opcode);
309 		else
310 			cmd->error = -EILSEQ;
311 	}
312 
313 	pxamci_disable_irq(host, END_CMD_RES);
314 	if (host->data && !cmd->error) {
315 		pxamci_enable_irq(host, DATA_TRAN_DONE);
316 		/*
317 		 * workaround for erratum #91, if doing write
318 		 * enable DMA late
319 		 */
320 		if (cpu_is_pxa27x() && host->data->flags & MMC_DATA_WRITE)
321 			dma_async_issue_pending(host->dma_chan_tx);
322 	} else {
323 		pxamci_finish_request(host, host->mrq);
324 	}
325 
326 	return 1;
327 }
328 
329 static int pxamci_data_done(struct pxamci_host *host, unsigned int stat)
330 {
331 	struct mmc_data *data = host->data;
332 	struct dma_chan *chan;
333 
334 	if (!data)
335 		return 0;
336 
337 	if (data->flags & MMC_DATA_READ)
338 		chan = host->dma_chan_rx;
339 	else
340 		chan = host->dma_chan_tx;
341 	dma_unmap_sg(chan->device->dev,
342 		     data->sg, data->sg_len, host->dma_dir);
343 
344 	if (stat & STAT_READ_TIME_OUT)
345 		data->error = -ETIMEDOUT;
346 	else if (stat & (STAT_CRC_READ_ERROR|STAT_CRC_WRITE_ERROR))
347 		data->error = -EILSEQ;
348 
349 	/*
350 	 * There appears to be a hardware design bug here.  There seems to
351 	 * be no way to find out how much data was transferred to the card.
352 	 * This means that if there was an error on any block, we mark all
353 	 * data blocks as being in error.
354 	 */
355 	if (!data->error)
356 		data->bytes_xfered = data->blocks * data->blksz;
357 	else
358 		data->bytes_xfered = 0;
359 
360 	pxamci_disable_irq(host, DATA_TRAN_DONE);
361 
362 	host->data = NULL;
363 	if (host->mrq->stop) {
364 		pxamci_stop_clock(host);
365 		pxamci_start_cmd(host, host->mrq->stop, host->cmdat);
366 	} else {
367 		pxamci_finish_request(host, host->mrq);
368 	}
369 
370 	return 1;
371 }
372 
373 static irqreturn_t pxamci_irq(int irq, void *devid)
374 {
375 	struct pxamci_host *host = devid;
376 	unsigned int ireg;
377 	int handled = 0;
378 
379 	ireg = readl(host->base + MMC_I_REG) & ~readl(host->base + MMC_I_MASK);
380 
381 	if (ireg) {
382 		unsigned stat = readl(host->base + MMC_STAT);
383 
384 		pr_debug("PXAMCI: irq %08x stat %08x\n", ireg, stat);
385 
386 		if (ireg & END_CMD_RES)
387 			handled |= pxamci_cmd_done(host, stat);
388 		if (ireg & DATA_TRAN_DONE)
389 			handled |= pxamci_data_done(host, stat);
390 		if (ireg & SDIO_INT) {
391 			mmc_signal_sdio_irq(host->mmc);
392 			handled = 1;
393 		}
394 	}
395 
396 	return IRQ_RETVAL(handled);
397 }
398 
399 static void pxamci_request(struct mmc_host *mmc, struct mmc_request *mrq)
400 {
401 	struct pxamci_host *host = mmc_priv(mmc);
402 	unsigned int cmdat;
403 
404 	WARN_ON(host->mrq != NULL);
405 
406 	host->mrq = mrq;
407 
408 	pxamci_stop_clock(host);
409 
410 	cmdat = host->cmdat;
411 	host->cmdat &= ~CMDAT_INIT;
412 
413 	if (mrq->data) {
414 		pxamci_setup_data(host, mrq->data);
415 
416 		cmdat &= ~CMDAT_BUSY;
417 		cmdat |= CMDAT_DATAEN | CMDAT_DMAEN;
418 		if (mrq->data->flags & MMC_DATA_WRITE)
419 			cmdat |= CMDAT_WRITE;
420 	}
421 
422 	pxamci_start_cmd(host, mrq->cmd, cmdat);
423 }
424 
425 static int pxamci_get_ro(struct mmc_host *mmc)
426 {
427 	struct pxamci_host *host = mmc_priv(mmc);
428 
429 	if (host->use_ro_gpio)
430 		return mmc_gpio_get_ro(mmc);
431 	if (host->pdata && host->pdata->get_ro)
432 		return !!host->pdata->get_ro(mmc_dev(mmc));
433 	/*
434 	 * Board doesn't support read only detection; let the mmc core
435 	 * decide what to do.
436 	 */
437 	return -ENOSYS;
438 }
439 
440 static void pxamci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
441 {
442 	struct pxamci_host *host = mmc_priv(mmc);
443 
444 	if (ios->clock) {
445 		unsigned long rate = host->clkrate;
446 		unsigned int clk = rate / ios->clock;
447 
448 		if (host->clkrt == CLKRT_OFF)
449 			clk_prepare_enable(host->clk);
450 
451 		if (ios->clock == 26000000) {
452 			/* to support 26MHz */
453 			host->clkrt = 7;
454 		} else {
455 			/* to handle (19.5MHz, 26MHz) */
456 			if (!clk)
457 				clk = 1;
458 
459 			/*
460 			 * clk might result in a lower divisor than we
461 			 * desire.  check for that condition and adjust
462 			 * as appropriate.
463 			 */
464 			if (rate / clk > ios->clock)
465 				clk <<= 1;
466 			host->clkrt = fls(clk) - 1;
467 		}
468 
469 		/*
470 		 * we write clkrt on the next command
471 		 */
472 	} else {
473 		pxamci_stop_clock(host);
474 		if (host->clkrt != CLKRT_OFF) {
475 			host->clkrt = CLKRT_OFF;
476 			clk_disable_unprepare(host->clk);
477 		}
478 	}
479 
480 	if (host->power_mode != ios->power_mode) {
481 		int ret;
482 
483 		host->power_mode = ios->power_mode;
484 
485 		ret = pxamci_set_power(host, ios->power_mode, ios->vdd);
486 		if (ret) {
487 			dev_err(mmc_dev(mmc), "unable to set power\n");
488 			/*
489 			 * The .set_ios() function in the mmc_host_ops
490 			 * struct return void, and failing to set the
491 			 * power should be rare so we print an error and
492 			 * return here.
493 			 */
494 			return;
495 		}
496 
497 		if (ios->power_mode == MMC_POWER_ON)
498 			host->cmdat |= CMDAT_INIT;
499 	}
500 
501 	if (ios->bus_width == MMC_BUS_WIDTH_4)
502 		host->cmdat |= CMDAT_SD_4DAT;
503 	else
504 		host->cmdat &= ~CMDAT_SD_4DAT;
505 
506 	dev_dbg(mmc_dev(mmc), "PXAMCI: clkrt = %x cmdat = %x\n",
507 		host->clkrt, host->cmdat);
508 }
509 
510 static void pxamci_enable_sdio_irq(struct mmc_host *host, int enable)
511 {
512 	struct pxamci_host *pxa_host = mmc_priv(host);
513 
514 	if (enable)
515 		pxamci_enable_irq(pxa_host, SDIO_INT);
516 	else
517 		pxamci_disable_irq(pxa_host, SDIO_INT);
518 }
519 
520 static const struct mmc_host_ops pxamci_ops = {
521 	.request		= pxamci_request,
522 	.get_cd			= mmc_gpio_get_cd,
523 	.get_ro			= pxamci_get_ro,
524 	.set_ios		= pxamci_set_ios,
525 	.enable_sdio_irq	= pxamci_enable_sdio_irq,
526 };
527 
528 static void pxamci_dma_irq(void *param)
529 {
530 	struct pxamci_host *host = param;
531 	struct dma_tx_state state;
532 	enum dma_status status;
533 	struct dma_chan *chan;
534 	unsigned long flags;
535 
536 	spin_lock_irqsave(&host->lock, flags);
537 
538 	if (!host->data)
539 		goto out_unlock;
540 
541 	if (host->data->flags & MMC_DATA_READ)
542 		chan = host->dma_chan_rx;
543 	else
544 		chan = host->dma_chan_tx;
545 
546 	status = dmaengine_tx_status(chan, host->dma_cookie, &state);
547 
548 	if (likely(status == DMA_COMPLETE)) {
549 		writel(BUF_PART_FULL, host->base + MMC_PRTBUF);
550 	} else {
551 		pr_err("%s: DMA error on %s channel\n", mmc_hostname(host->mmc),
552 			host->data->flags & MMC_DATA_READ ? "rx" : "tx");
553 		host->data->error = -EIO;
554 		pxamci_data_done(host, 0);
555 	}
556 
557 out_unlock:
558 	spin_unlock_irqrestore(&host->lock, flags);
559 }
560 
561 static irqreturn_t pxamci_detect_irq(int irq, void *devid)
562 {
563 	struct pxamci_host *host = mmc_priv(devid);
564 
565 	mmc_detect_change(devid, msecs_to_jiffies(host->detect_delay_ms));
566 	return IRQ_HANDLED;
567 }
568 
569 #ifdef CONFIG_OF
570 static const struct of_device_id pxa_mmc_dt_ids[] = {
571         { .compatible = "marvell,pxa-mmc" },
572         { }
573 };
574 
575 MODULE_DEVICE_TABLE(of, pxa_mmc_dt_ids);
576 
577 static int pxamci_of_init(struct platform_device *pdev,
578 			  struct mmc_host *mmc)
579 {
580 	struct device_node *np = pdev->dev.of_node;
581 	struct pxamci_host *host = mmc_priv(mmc);
582 	u32 tmp;
583 	int ret;
584 
585 	if (!np)
586 		return 0;
587 
588 	/* pxa-mmc specific */
589 	if (of_property_read_u32(np, "pxa-mmc,detect-delay-ms", &tmp) == 0)
590 		host->detect_delay_ms = tmp;
591 
592 	ret = mmc_of_parse(mmc);
593 	if (ret < 0)
594 		return ret;
595 
596 	return 0;
597 }
598 #else
599 static int pxamci_of_init(struct platform_device *pdev,
600 			  struct mmc_host *mmc)
601 {
602         return 0;
603 }
604 #endif
605 
606 static int pxamci_probe(struct platform_device *pdev)
607 {
608 	struct mmc_host *mmc;
609 	struct pxamci_host *host = NULL;
610 	struct device *dev = &pdev->dev;
611 	struct resource *r;
612 	int ret, irq;
613 
614 	irq = platform_get_irq(pdev, 0);
615 	if (irq < 0)
616 		return irq;
617 
618 	mmc = mmc_alloc_host(sizeof(struct pxamci_host), dev);
619 	if (!mmc) {
620 		ret = -ENOMEM;
621 		goto out;
622 	}
623 
624 	mmc->ops = &pxamci_ops;
625 
626 	/*
627 	 * We can do SG-DMA, but we don't because we never know how much
628 	 * data we successfully wrote to the card.
629 	 */
630 	mmc->max_segs = NR_SG;
631 
632 	/*
633 	 * Our hardware DMA can handle a maximum of one page per SG entry.
634 	 */
635 	mmc->max_seg_size = PAGE_SIZE;
636 
637 	/*
638 	 * Block length register is only 10 bits before PXA27x.
639 	 */
640 	mmc->max_blk_size = cpu_is_pxa25x() ? 1023 : 2048;
641 
642 	/*
643 	 * Block count register is 16 bits.
644 	 */
645 	mmc->max_blk_count = 65535;
646 
647 	ret = pxamci_of_init(pdev, mmc);
648 	if (ret)
649 		goto out;
650 
651 	host = mmc_priv(mmc);
652 	host->mmc = mmc;
653 	host->pdata = pdev->dev.platform_data;
654 	host->clkrt = CLKRT_OFF;
655 
656 	host->clk = devm_clk_get(dev, NULL);
657 	if (IS_ERR(host->clk)) {
658 		ret = PTR_ERR(host->clk);
659 		host->clk = NULL;
660 		goto out;
661 	}
662 
663 	host->clkrate = clk_get_rate(host->clk);
664 
665 	/*
666 	 * Calculate minimum clock rate, rounding up.
667 	 */
668 	mmc->f_min = (host->clkrate + 63) / 64;
669 	mmc->f_max = (mmc_has_26MHz()) ? 26000000 : host->clkrate;
670 
671 	ret = pxamci_init_ocr(host);
672 	if (ret < 0)
673 		goto out;
674 
675 	mmc->caps = 0;
676 	host->cmdat = 0;
677 	if (!cpu_is_pxa25x()) {
678 		mmc->caps |= MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
679 		host->cmdat |= CMDAT_SDIO_INT_EN;
680 		if (mmc_has_26MHz())
681 			mmc->caps |= MMC_CAP_MMC_HIGHSPEED |
682 				     MMC_CAP_SD_HIGHSPEED;
683 	}
684 
685 	spin_lock_init(&host->lock);
686 	host->imask = MMC_I_MASK_ALL;
687 
688 	host->base = devm_platform_get_and_ioremap_resource(pdev, 0, &r);
689 	if (IS_ERR(host->base)) {
690 		ret = PTR_ERR(host->base);
691 		goto out;
692 	}
693 	host->res = r;
694 
695 	/*
696 	 * Ensure that the host controller is shut down, and setup
697 	 * with our defaults.
698 	 */
699 	pxamci_stop_clock(host);
700 	writel(0, host->base + MMC_SPI);
701 	writel(64, host->base + MMC_RESTO);
702 	writel(host->imask, host->base + MMC_I_MASK);
703 
704 	ret = devm_request_irq(dev, irq, pxamci_irq, 0,
705 			       DRIVER_NAME, host);
706 	if (ret)
707 		goto out;
708 
709 	platform_set_drvdata(pdev, mmc);
710 
711 	host->dma_chan_rx = dma_request_chan(dev, "rx");
712 	if (IS_ERR(host->dma_chan_rx)) {
713 		dev_err(dev, "unable to request rx dma channel\n");
714 		ret = PTR_ERR(host->dma_chan_rx);
715 		host->dma_chan_rx = NULL;
716 		goto out;
717 	}
718 
719 	host->dma_chan_tx = dma_request_chan(dev, "tx");
720 	if (IS_ERR(host->dma_chan_tx)) {
721 		dev_err(dev, "unable to request tx dma channel\n");
722 		ret = PTR_ERR(host->dma_chan_tx);
723 		host->dma_chan_tx = NULL;
724 		goto out;
725 	}
726 
727 	if (host->pdata) {
728 		host->detect_delay_ms = host->pdata->detect_delay_ms;
729 
730 		host->power = devm_gpiod_get_optional(dev, "power", GPIOD_OUT_LOW);
731 		if (IS_ERR(host->power)) {
732 			ret = PTR_ERR(host->power);
733 			dev_err(dev, "Failed requesting gpio_power\n");
734 			goto out;
735 		}
736 
737 		/* FIXME: should we pass detection delay to debounce? */
738 		ret = mmc_gpiod_request_cd(mmc, "cd", 0, false, 0);
739 		if (ret && ret != -ENOENT) {
740 			dev_err(dev, "Failed requesting gpio_cd\n");
741 			goto out;
742 		}
743 
744 		if (!host->pdata->gpio_card_ro_invert)
745 			mmc->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
746 
747 		ret = mmc_gpiod_request_ro(mmc, "wp", 0, 0);
748 		if (ret && ret != -ENOENT) {
749 			dev_err(dev, "Failed requesting gpio_ro\n");
750 			goto out;
751 		}
752 		if (!ret)
753 			host->use_ro_gpio = true;
754 
755 		if (host->pdata->init)
756 			host->pdata->init(dev, pxamci_detect_irq, mmc);
757 
758 		if (host->power && host->pdata->setpower)
759 			dev_warn(dev, "gpio_power and setpower() both defined\n");
760 		if (host->use_ro_gpio && host->pdata->get_ro)
761 			dev_warn(dev, "gpio_ro and get_ro() both defined\n");
762 	}
763 
764 	ret = mmc_add_host(mmc);
765 	if (ret) {
766 		if (host->pdata && host->pdata->exit)
767 			host->pdata->exit(dev, mmc);
768 		goto out;
769 	}
770 
771 	return 0;
772 
773 out:
774 	if (host) {
775 		if (host->dma_chan_rx)
776 			dma_release_channel(host->dma_chan_rx);
777 		if (host->dma_chan_tx)
778 			dma_release_channel(host->dma_chan_tx);
779 	}
780 	if (mmc)
781 		mmc_free_host(mmc);
782 	return ret;
783 }
784 
785 static void pxamci_remove(struct platform_device *pdev)
786 {
787 	struct mmc_host *mmc = platform_get_drvdata(pdev);
788 
789 	if (mmc) {
790 		struct pxamci_host *host = mmc_priv(mmc);
791 
792 		mmc_remove_host(mmc);
793 
794 		if (host->pdata && host->pdata->exit)
795 			host->pdata->exit(&pdev->dev, mmc);
796 
797 		pxamci_stop_clock(host);
798 		writel(TXFIFO_WR_REQ|RXFIFO_RD_REQ|CLK_IS_OFF|STOP_CMD|
799 		       END_CMD_RES|PRG_DONE|DATA_TRAN_DONE,
800 		       host->base + MMC_I_MASK);
801 
802 		dmaengine_terminate_all(host->dma_chan_rx);
803 		dmaengine_terminate_all(host->dma_chan_tx);
804 		dma_release_channel(host->dma_chan_rx);
805 		dma_release_channel(host->dma_chan_tx);
806 
807 		mmc_free_host(mmc);
808 	}
809 }
810 
811 static struct platform_driver pxamci_driver = {
812 	.probe		= pxamci_probe,
813 	.remove_new	= pxamci_remove,
814 	.driver		= {
815 		.name	= DRIVER_NAME,
816 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
817 		.of_match_table = of_match_ptr(pxa_mmc_dt_ids),
818 	},
819 };
820 
821 module_platform_driver(pxamci_driver);
822 
823 MODULE_DESCRIPTION("PXA Multimedia Card Interface Driver");
824 MODULE_LICENSE("GPL");
825 MODULE_ALIAS("platform:pxa2xx-mci");
826