xref: /openbmc/linux/drivers/mmc/host/pxamci.c (revision d9fd5a71)
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/of_device.h>
34 
35 #include <linux/sizes.h>
36 
37 #include <mach/hardware.h>
38 #include <linux/platform_data/mmc-pxamci.h>
39 
40 #include "pxamci.h"
41 
42 #define DRIVER_NAME	"pxa2xx-mci"
43 
44 #define NR_SG	1
45 #define CLKRT_OFF	(~0)
46 
47 #define mmc_has_26MHz()		(cpu_is_pxa300() || cpu_is_pxa310() \
48 				|| cpu_is_pxa935())
49 
50 struct pxamci_host {
51 	struct mmc_host		*mmc;
52 	spinlock_t		lock;
53 	struct resource		*res;
54 	void __iomem		*base;
55 	struct clk		*clk;
56 	unsigned long		clkrate;
57 	unsigned int		clkrt;
58 	unsigned int		cmdat;
59 	unsigned int		imask;
60 	unsigned int		power_mode;
61 	unsigned long		detect_delay_ms;
62 	bool			use_ro_gpio;
63 	struct gpio_desc	*power;
64 	struct pxamci_platform_data *pdata;
65 
66 	struct mmc_request	*mrq;
67 	struct mmc_command	*cmd;
68 	struct mmc_data		*data;
69 
70 	struct dma_chan		*dma_chan_rx;
71 	struct dma_chan		*dma_chan_tx;
72 	dma_cookie_t		dma_cookie;
73 	unsigned int		dma_len;
74 	unsigned int		dma_dir;
75 };
76 
77 static int pxamci_init_ocr(struct pxamci_host *host)
78 {
79 	struct mmc_host *mmc = host->mmc;
80 	int ret;
81 
82 	ret = mmc_regulator_get_supply(mmc);
83 	if (ret < 0)
84 		return ret;
85 
86 	if (IS_ERR(mmc->supply.vmmc)) {
87 		/* fall-back to platform data */
88 		mmc->ocr_avail = host->pdata ?
89 			host->pdata->ocr_mask :
90 			MMC_VDD_32_33 | MMC_VDD_33_34;
91 	}
92 
93 	return 0;
94 }
95 
96 static inline int pxamci_set_power(struct pxamci_host *host,
97 				    unsigned char power_mode,
98 				    unsigned int vdd)
99 {
100 	struct mmc_host *mmc = host->mmc;
101 	struct regulator *supply = mmc->supply.vmmc;
102 
103 	if (!IS_ERR(supply))
104 		return mmc_regulator_set_ocr(mmc, supply, vdd);
105 
106 	if (host->power) {
107 		bool on = !!((1 << vdd) & host->pdata->ocr_mask);
108 		gpiod_set_value(host->power, on);
109 	}
110 
111 	if (host->pdata && host->pdata->setpower)
112 		return host->pdata->setpower(mmc_dev(host->mmc), vdd);
113 
114 	return 0;
115 }
116 
117 static void pxamci_stop_clock(struct pxamci_host *host)
118 {
119 	if (readl(host->base + MMC_STAT) & STAT_CLK_EN) {
120 		unsigned long timeout = 10000;
121 		unsigned int v;
122 
123 		writel(STOP_CLOCK, host->base + MMC_STRPCL);
124 
125 		do {
126 			v = readl(host->base + MMC_STAT);
127 			if (!(v & STAT_CLK_EN))
128 				break;
129 			udelay(1);
130 		} while (timeout--);
131 
132 		if (v & STAT_CLK_EN)
133 			dev_err(mmc_dev(host->mmc), "unable to stop clock\n");
134 	}
135 }
136 
137 static void pxamci_enable_irq(struct pxamci_host *host, unsigned int mask)
138 {
139 	unsigned long flags;
140 
141 	spin_lock_irqsave(&host->lock, flags);
142 	host->imask &= ~mask;
143 	writel(host->imask, host->base + MMC_I_MASK);
144 	spin_unlock_irqrestore(&host->lock, flags);
145 }
146 
147 static void pxamci_disable_irq(struct pxamci_host *host, unsigned int mask)
148 {
149 	unsigned long flags;
150 
151 	spin_lock_irqsave(&host->lock, flags);
152 	host->imask |= mask;
153 	writel(host->imask, host->base + MMC_I_MASK);
154 	spin_unlock_irqrestore(&host->lock, flags);
155 }
156 
157 static void pxamci_dma_irq(void *param);
158 
159 static void pxamci_setup_data(struct pxamci_host *host, struct mmc_data *data)
160 {
161 	struct dma_async_tx_descriptor *tx;
162 	enum dma_transfer_direction direction;
163 	struct dma_slave_config	config;
164 	struct dma_chan *chan;
165 	unsigned int nob = data->blocks;
166 	unsigned long long clks;
167 	unsigned int timeout;
168 	int ret;
169 
170 	host->data = data;
171 
172 	writel(nob, host->base + MMC_NOB);
173 	writel(data->blksz, host->base + MMC_BLKLEN);
174 
175 	clks = (unsigned long long)data->timeout_ns * host->clkrate;
176 	do_div(clks, 1000000000UL);
177 	timeout = (unsigned int)clks + (data->timeout_clks << host->clkrt);
178 	writel((timeout + 255) / 256, host->base + MMC_RDTO);
179 
180 	memset(&config, 0, sizeof(config));
181 	config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
182 	config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
183 	config.src_addr = host->res->start + MMC_RXFIFO;
184 	config.dst_addr = host->res->start + MMC_TXFIFO;
185 	config.src_maxburst = 32;
186 	config.dst_maxburst = 32;
187 
188 	if (data->flags & MMC_DATA_READ) {
189 		host->dma_dir = DMA_FROM_DEVICE;
190 		direction = DMA_DEV_TO_MEM;
191 		chan = host->dma_chan_rx;
192 	} else {
193 		host->dma_dir = DMA_TO_DEVICE;
194 		direction = DMA_MEM_TO_DEV;
195 		chan = host->dma_chan_tx;
196 	}
197 
198 	config.direction = direction;
199 
200 	ret = dmaengine_slave_config(chan, &config);
201 	if (ret < 0) {
202 		dev_err(mmc_dev(host->mmc), "dma slave config failed\n");
203 		return;
204 	}
205 
206 	host->dma_len = dma_map_sg(chan->device->dev, data->sg, data->sg_len,
207 				   host->dma_dir);
208 
209 	tx = dmaengine_prep_slave_sg(chan, data->sg, host->dma_len, direction,
210 				     DMA_PREP_INTERRUPT);
211 	if (!tx) {
212 		dev_err(mmc_dev(host->mmc), "prep_slave_sg() failed\n");
213 		return;
214 	}
215 
216 	if (!(data->flags & MMC_DATA_READ)) {
217 		tx->callback = pxamci_dma_irq;
218 		tx->callback_param = host;
219 	}
220 
221 	host->dma_cookie = dmaengine_submit(tx);
222 
223 	/*
224 	 * workaround for erratum #91:
225 	 * only start DMA now if we are doing a read,
226 	 * otherwise we wait until CMD/RESP has finished
227 	 * before starting DMA.
228 	 */
229 	if (!cpu_is_pxa27x() || data->flags & MMC_DATA_READ)
230 		dma_async_issue_pending(chan);
231 }
232 
233 static void pxamci_start_cmd(struct pxamci_host *host, struct mmc_command *cmd, unsigned int cmdat)
234 {
235 	WARN_ON(host->cmd != NULL);
236 	host->cmd = cmd;
237 
238 	if (cmd->flags & MMC_RSP_BUSY)
239 		cmdat |= CMDAT_BUSY;
240 
241 #define RSP_TYPE(x)	((x) & ~(MMC_RSP_BUSY|MMC_RSP_OPCODE))
242 	switch (RSP_TYPE(mmc_resp_type(cmd))) {
243 	case RSP_TYPE(MMC_RSP_R1): /* r1, r1b, r6, r7 */
244 		cmdat |= CMDAT_RESP_SHORT;
245 		break;
246 	case RSP_TYPE(MMC_RSP_R3):
247 		cmdat |= CMDAT_RESP_R3;
248 		break;
249 	case RSP_TYPE(MMC_RSP_R2):
250 		cmdat |= CMDAT_RESP_R2;
251 		break;
252 	default:
253 		break;
254 	}
255 
256 	writel(cmd->opcode, host->base + MMC_CMD);
257 	writel(cmd->arg >> 16, host->base + MMC_ARGH);
258 	writel(cmd->arg & 0xffff, host->base + MMC_ARGL);
259 	writel(cmdat, host->base + MMC_CMDAT);
260 	writel(host->clkrt, host->base + MMC_CLKRT);
261 
262 	writel(START_CLOCK, host->base + MMC_STRPCL);
263 
264 	pxamci_enable_irq(host, END_CMD_RES);
265 }
266 
267 static void pxamci_finish_request(struct pxamci_host *host, struct mmc_request *mrq)
268 {
269 	host->mrq = NULL;
270 	host->cmd = NULL;
271 	host->data = NULL;
272 	mmc_request_done(host->mmc, mrq);
273 }
274 
275 static int pxamci_cmd_done(struct pxamci_host *host, unsigned int stat)
276 {
277 	struct mmc_command *cmd = host->cmd;
278 	int i;
279 	u32 v;
280 
281 	if (!cmd)
282 		return 0;
283 
284 	host->cmd = NULL;
285 
286 	/*
287 	 * Did I mention this is Sick.  We always need to
288 	 * discard the upper 8 bits of the first 16-bit word.
289 	 */
290 	v = readl(host->base + MMC_RES) & 0xffff;
291 	for (i = 0; i < 4; i++) {
292 		u32 w1 = readl(host->base + MMC_RES) & 0xffff;
293 		u32 w2 = readl(host->base + MMC_RES) & 0xffff;
294 		cmd->resp[i] = v << 24 | w1 << 8 | w2 >> 8;
295 		v = w2;
296 	}
297 
298 	if (stat & STAT_TIME_OUT_RESPONSE) {
299 		cmd->error = -ETIMEDOUT;
300 	} else if (stat & STAT_RES_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
301 		/*
302 		 * workaround for erratum #42:
303 		 * Intel PXA27x Family Processor Specification Update Rev 001
304 		 * A bogus CRC error can appear if the msb of a 136 bit
305 		 * response is a one.
306 		 */
307 		if (cpu_is_pxa27x() &&
308 		    (cmd->flags & MMC_RSP_136 && cmd->resp[0] & 0x80000000))
309 			pr_debug("ignoring CRC from command %d - *risky*\n", cmd->opcode);
310 		else
311 			cmd->error = -EILSEQ;
312 	}
313 
314 	pxamci_disable_irq(host, END_CMD_RES);
315 	if (host->data && !cmd->error) {
316 		pxamci_enable_irq(host, DATA_TRAN_DONE);
317 		/*
318 		 * workaround for erratum #91, if doing write
319 		 * enable DMA late
320 		 */
321 		if (cpu_is_pxa27x() && host->data->flags & MMC_DATA_WRITE)
322 			dma_async_issue_pending(host->dma_chan_tx);
323 	} else {
324 		pxamci_finish_request(host, host->mrq);
325 	}
326 
327 	return 1;
328 }
329 
330 static int pxamci_data_done(struct pxamci_host *host, unsigned int stat)
331 {
332 	struct mmc_data *data = host->data;
333 	struct dma_chan *chan;
334 
335 	if (!data)
336 		return 0;
337 
338 	if (data->flags & MMC_DATA_READ)
339 		chan = host->dma_chan_rx;
340 	else
341 		chan = host->dma_chan_tx;
342 	dma_unmap_sg(chan->device->dev,
343 		     data->sg, data->sg_len, host->dma_dir);
344 
345 	if (stat & STAT_READ_TIME_OUT)
346 		data->error = -ETIMEDOUT;
347 	else if (stat & (STAT_CRC_READ_ERROR|STAT_CRC_WRITE_ERROR))
348 		data->error = -EILSEQ;
349 
350 	/*
351 	 * There appears to be a hardware design bug here.  There seems to
352 	 * be no way to find out how much data was transferred to the card.
353 	 * This means that if there was an error on any block, we mark all
354 	 * data blocks as being in error.
355 	 */
356 	if (!data->error)
357 		data->bytes_xfered = data->blocks * data->blksz;
358 	else
359 		data->bytes_xfered = 0;
360 
361 	pxamci_disable_irq(host, DATA_TRAN_DONE);
362 
363 	host->data = NULL;
364 	if (host->mrq->stop) {
365 		pxamci_stop_clock(host);
366 		pxamci_start_cmd(host, host->mrq->stop, host->cmdat);
367 	} else {
368 		pxamci_finish_request(host, host->mrq);
369 	}
370 
371 	return 1;
372 }
373 
374 static irqreturn_t pxamci_irq(int irq, void *devid)
375 {
376 	struct pxamci_host *host = devid;
377 	unsigned int ireg;
378 	int handled = 0;
379 
380 	ireg = readl(host->base + MMC_I_REG) & ~readl(host->base + MMC_I_MASK);
381 
382 	if (ireg) {
383 		unsigned stat = readl(host->base + MMC_STAT);
384 
385 		pr_debug("PXAMCI: irq %08x stat %08x\n", ireg, stat);
386 
387 		if (ireg & END_CMD_RES)
388 			handled |= pxamci_cmd_done(host, stat);
389 		if (ireg & DATA_TRAN_DONE)
390 			handled |= pxamci_data_done(host, stat);
391 		if (ireg & SDIO_INT) {
392 			mmc_signal_sdio_irq(host->mmc);
393 			handled = 1;
394 		}
395 	}
396 
397 	return IRQ_RETVAL(handled);
398 }
399 
400 static void pxamci_request(struct mmc_host *mmc, struct mmc_request *mrq)
401 {
402 	struct pxamci_host *host = mmc_priv(mmc);
403 	unsigned int cmdat;
404 
405 	WARN_ON(host->mrq != NULL);
406 
407 	host->mrq = mrq;
408 
409 	pxamci_stop_clock(host);
410 
411 	cmdat = host->cmdat;
412 	host->cmdat &= ~CMDAT_INIT;
413 
414 	if (mrq->data) {
415 		pxamci_setup_data(host, mrq->data);
416 
417 		cmdat &= ~CMDAT_BUSY;
418 		cmdat |= CMDAT_DATAEN | CMDAT_DMAEN;
419 		if (mrq->data->flags & MMC_DATA_WRITE)
420 			cmdat |= CMDAT_WRITE;
421 	}
422 
423 	pxamci_start_cmd(host, mrq->cmd, cmdat);
424 }
425 
426 static int pxamci_get_ro(struct mmc_host *mmc)
427 {
428 	struct pxamci_host *host = mmc_priv(mmc);
429 
430 	if (host->use_ro_gpio)
431 		return mmc_gpio_get_ro(mmc);
432 	if (host->pdata && host->pdata->get_ro)
433 		return !!host->pdata->get_ro(mmc_dev(mmc));
434 	/*
435 	 * Board doesn't support read only detection; let the mmc core
436 	 * decide what to do.
437 	 */
438 	return -ENOSYS;
439 }
440 
441 static void pxamci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
442 {
443 	struct pxamci_host *host = mmc_priv(mmc);
444 
445 	if (ios->clock) {
446 		unsigned long rate = host->clkrate;
447 		unsigned int clk = rate / ios->clock;
448 
449 		if (host->clkrt == CLKRT_OFF)
450 			clk_prepare_enable(host->clk);
451 
452 		if (ios->clock == 26000000) {
453 			/* to support 26MHz */
454 			host->clkrt = 7;
455 		} else {
456 			/* to handle (19.5MHz, 26MHz) */
457 			if (!clk)
458 				clk = 1;
459 
460 			/*
461 			 * clk might result in a lower divisor than we
462 			 * desire.  check for that condition and adjust
463 			 * as appropriate.
464 			 */
465 			if (rate / clk > ios->clock)
466 				clk <<= 1;
467 			host->clkrt = fls(clk) - 1;
468 		}
469 
470 		/*
471 		 * we write clkrt on the next command
472 		 */
473 	} else {
474 		pxamci_stop_clock(host);
475 		if (host->clkrt != CLKRT_OFF) {
476 			host->clkrt = CLKRT_OFF;
477 			clk_disable_unprepare(host->clk);
478 		}
479 	}
480 
481 	if (host->power_mode != ios->power_mode) {
482 		int ret;
483 
484 		host->power_mode = ios->power_mode;
485 
486 		ret = pxamci_set_power(host, ios->power_mode, ios->vdd);
487 		if (ret) {
488 			dev_err(mmc_dev(mmc), "unable to set power\n");
489 			/*
490 			 * The .set_ios() function in the mmc_host_ops
491 			 * struct return void, and failing to set the
492 			 * power should be rare so we print an error and
493 			 * return here.
494 			 */
495 			return;
496 		}
497 
498 		if (ios->power_mode == MMC_POWER_ON)
499 			host->cmdat |= CMDAT_INIT;
500 	}
501 
502 	if (ios->bus_width == MMC_BUS_WIDTH_4)
503 		host->cmdat |= CMDAT_SD_4DAT;
504 	else
505 		host->cmdat &= ~CMDAT_SD_4DAT;
506 
507 	dev_dbg(mmc_dev(mmc), "PXAMCI: clkrt = %x cmdat = %x\n",
508 		host->clkrt, host->cmdat);
509 }
510 
511 static void pxamci_enable_sdio_irq(struct mmc_host *host, int enable)
512 {
513 	struct pxamci_host *pxa_host = mmc_priv(host);
514 
515 	if (enable)
516 		pxamci_enable_irq(pxa_host, SDIO_INT);
517 	else
518 		pxamci_disable_irq(pxa_host, SDIO_INT);
519 }
520 
521 static const struct mmc_host_ops pxamci_ops = {
522 	.request		= pxamci_request,
523 	.get_cd			= mmc_gpio_get_cd,
524 	.get_ro			= pxamci_get_ro,
525 	.set_ios		= pxamci_set_ios,
526 	.enable_sdio_irq	= pxamci_enable_sdio_irq,
527 };
528 
529 static void pxamci_dma_irq(void *param)
530 {
531 	struct pxamci_host *host = param;
532 	struct dma_tx_state state;
533 	enum dma_status status;
534 	struct dma_chan *chan;
535 	unsigned long flags;
536 
537 	spin_lock_irqsave(&host->lock, flags);
538 
539 	if (!host->data)
540 		goto out_unlock;
541 
542 	if (host->data->flags & MMC_DATA_READ)
543 		chan = host->dma_chan_rx;
544 	else
545 		chan = host->dma_chan_tx;
546 
547 	status = dmaengine_tx_status(chan, host->dma_cookie, &state);
548 
549 	if (likely(status == DMA_COMPLETE)) {
550 		writel(BUF_PART_FULL, host->base + MMC_PRTBUF);
551 	} else {
552 		pr_err("%s: DMA error on %s channel\n", mmc_hostname(host->mmc),
553 			host->data->flags & MMC_DATA_READ ? "rx" : "tx");
554 		host->data->error = -EIO;
555 		pxamci_data_done(host, 0);
556 	}
557 
558 out_unlock:
559 	spin_unlock_irqrestore(&host->lock, flags);
560 }
561 
562 static irqreturn_t pxamci_detect_irq(int irq, void *devid)
563 {
564 	struct pxamci_host *host = mmc_priv(devid);
565 
566 	mmc_detect_change(devid, msecs_to_jiffies(host->detect_delay_ms));
567 	return IRQ_HANDLED;
568 }
569 
570 #ifdef CONFIG_OF
571 static const struct of_device_id pxa_mmc_dt_ids[] = {
572         { .compatible = "marvell,pxa-mmc" },
573         { }
574 };
575 
576 MODULE_DEVICE_TABLE(of, pxa_mmc_dt_ids);
577 
578 static int pxamci_of_init(struct platform_device *pdev,
579 			  struct mmc_host *mmc)
580 {
581 	struct device_node *np = pdev->dev.of_node;
582 	struct pxamci_host *host = mmc_priv(mmc);
583 	u32 tmp;
584 	int ret;
585 
586 	if (!np)
587 		return 0;
588 
589 	/* pxa-mmc specific */
590 	if (of_property_read_u32(np, "pxa-mmc,detect-delay-ms", &tmp) == 0)
591 		host->detect_delay_ms = tmp;
592 
593 	ret = mmc_of_parse(mmc);
594 	if (ret < 0)
595 		return ret;
596 
597 	return 0;
598 }
599 #else
600 static int pxamci_of_init(struct platform_device *pdev,
601 			  struct mmc_host *mmc)
602 {
603         return 0;
604 }
605 #endif
606 
607 static int pxamci_probe(struct platform_device *pdev)
608 {
609 	struct mmc_host *mmc;
610 	struct pxamci_host *host = NULL;
611 	struct device *dev = &pdev->dev;
612 	struct resource *r;
613 	int ret, irq;
614 
615 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
616 	irq = platform_get_irq(pdev, 0);
617 	if (irq < 0)
618 		return irq;
619 
620 	mmc = mmc_alloc_host(sizeof(struct pxamci_host), dev);
621 	if (!mmc) {
622 		ret = -ENOMEM;
623 		goto out;
624 	}
625 
626 	mmc->ops = &pxamci_ops;
627 
628 	/*
629 	 * We can do SG-DMA, but we don't because we never know how much
630 	 * data we successfully wrote to the card.
631 	 */
632 	mmc->max_segs = NR_SG;
633 
634 	/*
635 	 * Our hardware DMA can handle a maximum of one page per SG entry.
636 	 */
637 	mmc->max_seg_size = PAGE_SIZE;
638 
639 	/*
640 	 * Block length register is only 10 bits before PXA27x.
641 	 */
642 	mmc->max_blk_size = cpu_is_pxa25x() ? 1023 : 2048;
643 
644 	/*
645 	 * Block count register is 16 bits.
646 	 */
647 	mmc->max_blk_count = 65535;
648 
649 	ret = pxamci_of_init(pdev, mmc);
650 	if (ret)
651 		return ret;
652 
653 	host = mmc_priv(mmc);
654 	host->mmc = mmc;
655 	host->pdata = pdev->dev.platform_data;
656 	host->clkrt = CLKRT_OFF;
657 
658 	host->clk = devm_clk_get(dev, NULL);
659 	if (IS_ERR(host->clk)) {
660 		ret = PTR_ERR(host->clk);
661 		host->clk = NULL;
662 		goto out;
663 	}
664 
665 	host->clkrate = clk_get_rate(host->clk);
666 
667 	/*
668 	 * Calculate minimum clock rate, rounding up.
669 	 */
670 	mmc->f_min = (host->clkrate + 63) / 64;
671 	mmc->f_max = (mmc_has_26MHz()) ? 26000000 : host->clkrate;
672 
673 	ret = pxamci_init_ocr(host);
674 	if (ret < 0)
675 		return ret;
676 
677 	mmc->caps = 0;
678 	host->cmdat = 0;
679 	if (!cpu_is_pxa25x()) {
680 		mmc->caps |= MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
681 		host->cmdat |= CMDAT_SDIO_INT_EN;
682 		if (mmc_has_26MHz())
683 			mmc->caps |= MMC_CAP_MMC_HIGHSPEED |
684 				     MMC_CAP_SD_HIGHSPEED;
685 	}
686 
687 	spin_lock_init(&host->lock);
688 	host->res = r;
689 	host->imask = MMC_I_MASK_ALL;
690 
691 	host->base = devm_ioremap_resource(dev, r);
692 	if (IS_ERR(host->base)) {
693 		ret = PTR_ERR(host->base);
694 		goto out;
695 	}
696 
697 	/*
698 	 * Ensure that the host controller is shut down, and setup
699 	 * with our defaults.
700 	 */
701 	pxamci_stop_clock(host);
702 	writel(0, host->base + MMC_SPI);
703 	writel(64, host->base + MMC_RESTO);
704 	writel(host->imask, host->base + MMC_I_MASK);
705 
706 	ret = devm_request_irq(dev, irq, pxamci_irq, 0,
707 			       DRIVER_NAME, host);
708 	if (ret)
709 		goto out;
710 
711 	platform_set_drvdata(pdev, mmc);
712 
713 	host->dma_chan_rx = dma_request_chan(dev, "rx");
714 	if (IS_ERR(host->dma_chan_rx)) {
715 		dev_err(dev, "unable to request rx dma channel\n");
716 		ret = PTR_ERR(host->dma_chan_rx);
717 		host->dma_chan_rx = NULL;
718 		goto out;
719 	}
720 
721 	host->dma_chan_tx = dma_request_chan(dev, "tx");
722 	if (IS_ERR(host->dma_chan_tx)) {
723 		dev_err(dev, "unable to request tx dma channel\n");
724 		ret = PTR_ERR(host->dma_chan_tx);
725 		host->dma_chan_tx = NULL;
726 		goto out;
727 	}
728 
729 	if (host->pdata) {
730 		host->detect_delay_ms = host->pdata->detect_delay_ms;
731 
732 		host->power = devm_gpiod_get_optional(dev, "power", GPIOD_OUT_LOW);
733 		if (IS_ERR(host->power)) {
734 			ret = PTR_ERR(host->power);
735 			dev_err(dev, "Failed requesting gpio_power\n");
736 			goto out;
737 		}
738 
739 		/* FIXME: should we pass detection delay to debounce? */
740 		ret = mmc_gpiod_request_cd(mmc, "cd", 0, false, 0);
741 		if (ret && ret != -ENOENT) {
742 			dev_err(dev, "Failed requesting gpio_cd\n");
743 			goto out;
744 		}
745 
746 		if (!host->pdata->gpio_card_ro_invert)
747 			mmc->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
748 
749 		ret = mmc_gpiod_request_ro(mmc, "wp", 0, 0);
750 		if (ret && ret != -ENOENT) {
751 			dev_err(dev, "Failed requesting gpio_ro\n");
752 			goto out;
753 		}
754 		if (!ret)
755 			host->use_ro_gpio = true;
756 
757 		if (host->pdata->init)
758 			host->pdata->init(dev, pxamci_detect_irq, mmc);
759 
760 		if (host->power && host->pdata->setpower)
761 			dev_warn(dev, "gpio_power and setpower() both defined\n");
762 		if (host->use_ro_gpio && host->pdata->get_ro)
763 			dev_warn(dev, "gpio_ro and get_ro() both defined\n");
764 	}
765 
766 	mmc_add_host(mmc);
767 
768 	return 0;
769 
770 out:
771 	if (host) {
772 		if (host->dma_chan_rx)
773 			dma_release_channel(host->dma_chan_rx);
774 		if (host->dma_chan_tx)
775 			dma_release_channel(host->dma_chan_tx);
776 	}
777 	if (mmc)
778 		mmc_free_host(mmc);
779 	return ret;
780 }
781 
782 static int pxamci_remove(struct platform_device *pdev)
783 {
784 	struct mmc_host *mmc = platform_get_drvdata(pdev);
785 
786 	if (mmc) {
787 		struct pxamci_host *host = mmc_priv(mmc);
788 
789 		mmc_remove_host(mmc);
790 
791 		if (host->pdata && host->pdata->exit)
792 			host->pdata->exit(&pdev->dev, mmc);
793 
794 		pxamci_stop_clock(host);
795 		writel(TXFIFO_WR_REQ|RXFIFO_RD_REQ|CLK_IS_OFF|STOP_CMD|
796 		       END_CMD_RES|PRG_DONE|DATA_TRAN_DONE,
797 		       host->base + MMC_I_MASK);
798 
799 		dmaengine_terminate_all(host->dma_chan_rx);
800 		dmaengine_terminate_all(host->dma_chan_tx);
801 		dma_release_channel(host->dma_chan_rx);
802 		dma_release_channel(host->dma_chan_tx);
803 
804 		mmc_free_host(mmc);
805 	}
806 
807 	return 0;
808 }
809 
810 static struct platform_driver pxamci_driver = {
811 	.probe		= pxamci_probe,
812 	.remove		= pxamci_remove,
813 	.driver		= {
814 		.name	= DRIVER_NAME,
815 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
816 		.of_match_table = of_match_ptr(pxa_mmc_dt_ids),
817 	},
818 };
819 
820 module_platform_driver(pxamci_driver);
821 
822 MODULE_DESCRIPTION("PXA Multimedia Card Interface Driver");
823 MODULE_LICENSE("GPL");
824 MODULE_ALIAS("platform:pxa2xx-mci");
825