pxamci.c 20.7 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881
/*
 *  linux/drivers/mmc/host/pxa.c - PXA MMCI driver
 *
 *  Copyright (C) 2003 Russell King, All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 *  This hardware is really sick:
 *   - No way to clear interrupts.
 *   - Have to turn off the clock whenever we touch the device.
 *   - Doesn't tell you how many data blocks were transferred.
 *  Yuck!
 *
 *	1 and 3 byte data transfers not supported
 *	max block length up to 1023
 */
#include <linux/module.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/dma/pxa-dma.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/mmc/host.h>
#include <linux/mmc/slot-gpio.h>
#include <linux/io.h>
#include <linux/regulator/consumer.h>
#include <linux/gpio.h>
#include <linux/gfp.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/of_device.h>

#include <asm/sizes.h>

#include <mach/hardware.h>
#include <linux/platform_data/mmc-pxamci.h>

#include "pxamci.h"

#define DRIVER_NAME	"pxa2xx-mci"

#define NR_SG	1
#define CLKRT_OFF	(~0)

#define mmc_has_26MHz()		(cpu_is_pxa300() || cpu_is_pxa310() \
				|| cpu_is_pxa935())

struct pxamci_host {
	struct mmc_host		*mmc;
	spinlock_t		lock;
	struct resource		*res;
	void __iomem		*base;
	struct clk		*clk;
	unsigned long		clkrate;
	int			irq;
	unsigned int		clkrt;
	unsigned int		cmdat;
	unsigned int		imask;
	unsigned int		power_mode;
	struct pxamci_platform_data *pdata;

	struct mmc_request	*mrq;
	struct mmc_command	*cmd;
	struct mmc_data		*data;

	struct dma_chan		*dma_chan_rx;
	struct dma_chan		*dma_chan_tx;
	dma_cookie_t		dma_cookie;
	dma_addr_t		sg_dma;
	unsigned int		dma_len;

	unsigned int		dma_dir;
	unsigned int		dma_drcmrrx;
	unsigned int		dma_drcmrtx;

	struct regulator	*vcc;
};

static inline void pxamci_init_ocr(struct pxamci_host *host)
{
#ifdef CONFIG_REGULATOR
	host->vcc = devm_regulator_get_optional(mmc_dev(host->mmc), "vmmc");

	if (IS_ERR(host->vcc))
		host->vcc = NULL;
	else {
		host->mmc->ocr_avail = mmc_regulator_get_ocrmask(host->vcc);
		if (host->pdata && host->pdata->ocr_mask)
			dev_warn(mmc_dev(host->mmc),
				"ocr_mask/setpower will not be used\n");
	}
#endif
	if (host->vcc == NULL) {
		/* fall-back to platform data */
		host->mmc->ocr_avail = host->pdata ?
			host->pdata->ocr_mask :
			MMC_VDD_32_33 | MMC_VDD_33_34;
	}
}

static inline int pxamci_set_power(struct pxamci_host *host,
				    unsigned char power_mode,
				    unsigned int vdd)
{
	int on;

	if (host->vcc) {
		int ret;

		if (power_mode == MMC_POWER_UP) {
			ret = mmc_regulator_set_ocr(host->mmc, host->vcc, vdd);
			if (ret)
				return ret;
		} else if (power_mode == MMC_POWER_OFF) {
			ret = mmc_regulator_set_ocr(host->mmc, host->vcc, 0);
			if (ret)
				return ret;
		}
	}
	if (!host->vcc && host->pdata &&
	    gpio_is_valid(host->pdata->gpio_power)) {
		on = ((1 << vdd) & host->pdata->ocr_mask);
		gpio_set_value(host->pdata->gpio_power,
			       !!on ^ host->pdata->gpio_power_invert);
	}
	if (!host->vcc && host->pdata && host->pdata->setpower)
		return host->pdata->setpower(mmc_dev(host->mmc), vdd);

	return 0;
}

static void pxamci_stop_clock(struct pxamci_host *host)
{
	if (readl(host->base + MMC_STAT) & STAT_CLK_EN) {
		unsigned long timeout = 10000;
		unsigned int v;

		writel(STOP_CLOCK, host->base + MMC_STRPCL);

		do {
			v = readl(host->base + MMC_STAT);
			if (!(v & STAT_CLK_EN))
				break;
			udelay(1);
		} while (timeout--);

		if (v & STAT_CLK_EN)
			dev_err(mmc_dev(host->mmc), "unable to stop clock\n");
	}
}

static void pxamci_enable_irq(struct pxamci_host *host, unsigned int mask)
{
	unsigned long flags;

	spin_lock_irqsave(&host->lock, flags);
	host->imask &= ~mask;
	writel(host->imask, host->base + MMC_I_MASK);
	spin_unlock_irqrestore(&host->lock, flags);
}

static void pxamci_disable_irq(struct pxamci_host *host, unsigned int mask)
{
	unsigned long flags;

	spin_lock_irqsave(&host->lock, flags);
	host->imask |= mask;
	writel(host->imask, host->base + MMC_I_MASK);
	spin_unlock_irqrestore(&host->lock, flags);
}

static void pxamci_dma_irq(void *param);

static void pxamci_setup_data(struct pxamci_host *host, struct mmc_data *data)
{
	struct dma_async_tx_descriptor *tx;
	enum dma_data_direction direction;
	struct dma_slave_config	config;
	struct dma_chan *chan;
	unsigned int nob = data->blocks;
	unsigned long long clks;
	unsigned int timeout;
	int ret;

	host->data = data;

	writel(nob, host->base + MMC_NOB);
	writel(data->blksz, host->base + MMC_BLKLEN);

	clks = (unsigned long long)data->timeout_ns * host->clkrate;
	do_div(clks, 1000000000UL);
	timeout = (unsigned int)clks + (data->timeout_clks << host->clkrt);
	writel((timeout + 255) / 256, host->base + MMC_RDTO);

	memset(&config, 0, sizeof(config));
	config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
	config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
	config.src_addr = host->res->start + MMC_RXFIFO;
	config.dst_addr = host->res->start + MMC_TXFIFO;
	config.src_maxburst = 32;
	config.dst_maxburst = 32;

	if (data->flags & MMC_DATA_READ) {
		host->dma_dir = DMA_FROM_DEVICE;
		direction = DMA_DEV_TO_MEM;
		chan = host->dma_chan_rx;
	} else {
		host->dma_dir = DMA_TO_DEVICE;
		direction = DMA_MEM_TO_DEV;
		chan = host->dma_chan_tx;
	}

	config.direction = direction;

	ret = dmaengine_slave_config(chan, &config);
	if (ret < 0) {
		dev_err(mmc_dev(host->mmc), "dma slave config failed\n");
		return;
	}

	host->dma_len = dma_map_sg(chan->device->dev, data->sg, data->sg_len,
				   host->dma_dir);

	tx = dmaengine_prep_slave_sg(chan, data->sg, host->dma_len, direction,
				     DMA_PREP_INTERRUPT);
	if (!tx) {
		dev_err(mmc_dev(host->mmc), "prep_slave_sg() failed\n");
		return;
	}

	if (!(data->flags & MMC_DATA_READ)) {
		tx->callback = pxamci_dma_irq;
		tx->callback_param = host;
	}

	host->dma_cookie = dmaengine_submit(tx);

	/*
	 * workaround for erratum #91:
	 * only start DMA now if we are doing a read,
	 * otherwise we wait until CMD/RESP has finished
	 * before starting DMA.
	 */
	if (!cpu_is_pxa27x() || data->flags & MMC_DATA_READ)
		dma_async_issue_pending(chan);
}

static void pxamci_start_cmd(struct pxamci_host *host, struct mmc_command *cmd, unsigned int cmdat)
{
	WARN_ON(host->cmd != NULL);
	host->cmd = cmd;

	if (cmd->flags & MMC_RSP_BUSY)
		cmdat |= CMDAT_BUSY;

#define RSP_TYPE(x)	((x) & ~(MMC_RSP_BUSY|MMC_RSP_OPCODE))
	switch (RSP_TYPE(mmc_resp_type(cmd))) {
	case RSP_TYPE(MMC_RSP_R1): /* r1, r1b, r6, r7 */
		cmdat |= CMDAT_RESP_SHORT;
		break;
	case RSP_TYPE(MMC_RSP_R3):
		cmdat |= CMDAT_RESP_R3;
		break;
	case RSP_TYPE(MMC_RSP_R2):
		cmdat |= CMDAT_RESP_R2;
		break;
	default:
		break;
	}

	writel(cmd->opcode, host->base + MMC_CMD);
	writel(cmd->arg >> 16, host->base + MMC_ARGH);
	writel(cmd->arg & 0xffff, host->base + MMC_ARGL);
	writel(cmdat, host->base + MMC_CMDAT);
	writel(host->clkrt, host->base + MMC_CLKRT);

	writel(START_CLOCK, host->base + MMC_STRPCL);

	pxamci_enable_irq(host, END_CMD_RES);
}

static void pxamci_finish_request(struct pxamci_host *host, struct mmc_request *mrq)
{
	host->mrq = NULL;
	host->cmd = NULL;
	host->data = NULL;
	mmc_request_done(host->mmc, mrq);
}

static int pxamci_cmd_done(struct pxamci_host *host, unsigned int stat)
{
	struct mmc_command *cmd = host->cmd;
	int i;
	u32 v;

	if (!cmd)
		return 0;

	host->cmd = NULL;

	/*
	 * Did I mention this is Sick.  We always need to
	 * discard the upper 8 bits of the first 16-bit word.
	 */
	v = readl(host->base + MMC_RES) & 0xffff;
	for (i = 0; i < 4; i++) {
		u32 w1 = readl(host->base + MMC_RES) & 0xffff;
		u32 w2 = readl(host->base + MMC_RES) & 0xffff;
		cmd->resp[i] = v << 24 | w1 << 8 | w2 >> 8;
		v = w2;
	}

	if (stat & STAT_TIME_OUT_RESPONSE) {
		cmd->error = -ETIMEDOUT;
	} else if (stat & STAT_RES_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
		/*
		 * workaround for erratum #42:
		 * Intel PXA27x Family Processor Specification Update Rev 001
		 * A bogus CRC error can appear if the msb of a 136 bit
		 * response is a one.
		 */
		if (cpu_is_pxa27x() &&
		    (cmd->flags & MMC_RSP_136 && cmd->resp[0] & 0x80000000))
			pr_debug("ignoring CRC from command %d - *risky*\n", cmd->opcode);
		else
			cmd->error = -EILSEQ;
	}

	pxamci_disable_irq(host, END_CMD_RES);
	if (host->data && !cmd->error) {
		pxamci_enable_irq(host, DATA_TRAN_DONE);
		/*
		 * workaround for erratum #91, if doing write
		 * enable DMA late
		 */
		if (cpu_is_pxa27x() && host->data->flags & MMC_DATA_WRITE)
			dma_async_issue_pending(host->dma_chan_tx);
	} else {
		pxamci_finish_request(host, host->mrq);
	}

	return 1;
}

static int pxamci_data_done(struct pxamci_host *host, unsigned int stat)
{
	struct mmc_data *data = host->data;
	struct dma_chan *chan;

	if (!data)
		return 0;

	if (data->flags & MMC_DATA_READ)
		chan = host->dma_chan_rx;
	else
		chan = host->dma_chan_tx;
	dma_unmap_sg(chan->device->dev,
		     data->sg, data->sg_len, host->dma_dir);

	if (stat & STAT_READ_TIME_OUT)
		data->error = -ETIMEDOUT;
	else if (stat & (STAT_CRC_READ_ERROR|STAT_CRC_WRITE_ERROR))
		data->error = -EILSEQ;

	/*
	 * There appears to be a hardware design bug here.  There seems to
	 * be no way to find out how much data was transferred to the card.
	 * This means that if there was an error on any block, we mark all
	 * data blocks as being in error.
	 */
	if (!data->error)
		data->bytes_xfered = data->blocks * data->blksz;
	else
		data->bytes_xfered = 0;

	pxamci_disable_irq(host, DATA_TRAN_DONE);

	host->data = NULL;
	if (host->mrq->stop) {
		pxamci_stop_clock(host);
		pxamci_start_cmd(host, host->mrq->stop, host->cmdat);
	} else {
		pxamci_finish_request(host, host->mrq);
	}

	return 1;
}

static irqreturn_t pxamci_irq(int irq, void *devid)
{
	struct pxamci_host *host = devid;
	unsigned int ireg;
	int handled = 0;

	ireg = readl(host->base + MMC_I_REG) & ~readl(host->base + MMC_I_MASK);

	if (ireg) {
		unsigned stat = readl(host->base + MMC_STAT);

		pr_debug("PXAMCI: irq %08x stat %08x\n", ireg, stat);

		if (ireg & END_CMD_RES)
			handled |= pxamci_cmd_done(host, stat);
		if (ireg & DATA_TRAN_DONE)
			handled |= pxamci_data_done(host, stat);
		if (ireg & SDIO_INT) {
			mmc_signal_sdio_irq(host->mmc);
			handled = 1;
		}
	}

	return IRQ_RETVAL(handled);
}

static void pxamci_request(struct mmc_host *mmc, struct mmc_request *mrq)
{
	struct pxamci_host *host = mmc_priv(mmc);
	unsigned int cmdat;

	WARN_ON(host->mrq != NULL);

	host->mrq = mrq;

	pxamci_stop_clock(host);

	cmdat = host->cmdat;
	host->cmdat &= ~CMDAT_INIT;

	if (mrq->data) {
		pxamci_setup_data(host, mrq->data);

		cmdat &= ~CMDAT_BUSY;
		cmdat |= CMDAT_DATAEN | CMDAT_DMAEN;
		if (mrq->data->flags & MMC_DATA_WRITE)
			cmdat |= CMDAT_WRITE;
	}

	pxamci_start_cmd(host, mrq->cmd, cmdat);
}

static int pxamci_get_ro(struct mmc_host *mmc)
{
	struct pxamci_host *host = mmc_priv(mmc);

	if (host->pdata && gpio_is_valid(host->pdata->gpio_card_ro))
		return mmc_gpio_get_ro(mmc);
	if (host->pdata && host->pdata->get_ro)
		return !!host->pdata->get_ro(mmc_dev(mmc));
	/*
	 * Board doesn't support read only detection; let the mmc core
	 * decide what to do.
	 */
	return -ENOSYS;
}

static void pxamci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
	struct pxamci_host *host = mmc_priv(mmc);

	if (ios->clock) {
		unsigned long rate = host->clkrate;
		unsigned int clk = rate / ios->clock;

		if (host->clkrt == CLKRT_OFF)
			clk_prepare_enable(host->clk);

		if (ios->clock == 26000000) {
			/* to support 26MHz */
			host->clkrt = 7;
		} else {
			/* to handle (19.5MHz, 26MHz) */
			if (!clk)
				clk = 1;

			/*
			 * clk might result in a lower divisor than we
			 * desire.  check for that condition and adjust
			 * as appropriate.
			 */
			if (rate / clk > ios->clock)
				clk <<= 1;
			host->clkrt = fls(clk) - 1;
		}

		/*
		 * we write clkrt on the next command
		 */
	} else {
		pxamci_stop_clock(host);
		if (host->clkrt != CLKRT_OFF) {
			host->clkrt = CLKRT_OFF;
			clk_disable_unprepare(host->clk);
		}
	}

	if (host->power_mode != ios->power_mode) {
		int ret;

		host->power_mode = ios->power_mode;

		ret = pxamci_set_power(host, ios->power_mode, ios->vdd);
		if (ret) {
			dev_err(mmc_dev(mmc), "unable to set power\n");
			/*
			 * The .set_ios() function in the mmc_host_ops
			 * struct return void, and failing to set the
			 * power should be rare so we print an error and
			 * return here.
			 */
			return;
		}

		if (ios->power_mode == MMC_POWER_ON)
			host->cmdat |= CMDAT_INIT;
	}

	if (ios->bus_width == MMC_BUS_WIDTH_4)
		host->cmdat |= CMDAT_SD_4DAT;
	else
		host->cmdat &= ~CMDAT_SD_4DAT;

	dev_dbg(mmc_dev(mmc), "PXAMCI: clkrt = %x cmdat = %x\n",
		host->clkrt, host->cmdat);
}

static void pxamci_enable_sdio_irq(struct mmc_host *host, int enable)
{
	struct pxamci_host *pxa_host = mmc_priv(host);

	if (enable)
		pxamci_enable_irq(pxa_host, SDIO_INT);
	else
		pxamci_disable_irq(pxa_host, SDIO_INT);
}

static const struct mmc_host_ops pxamci_ops = {
	.request		= pxamci_request,
	.get_cd			= mmc_gpio_get_cd,
	.get_ro			= pxamci_get_ro,
	.set_ios		= pxamci_set_ios,
	.enable_sdio_irq	= pxamci_enable_sdio_irq,
};

static void pxamci_dma_irq(void *param)
{
	struct pxamci_host *host = param;
	struct dma_tx_state state;
	enum dma_status status;
	struct dma_chan *chan;
	unsigned long flags;

	spin_lock_irqsave(&host->lock, flags);

	if (!host->data)
		goto out_unlock;

	if (host->data->flags & MMC_DATA_READ)
		chan = host->dma_chan_rx;
	else
		chan = host->dma_chan_tx;

	status = dmaengine_tx_status(chan, host->dma_cookie, &state);

	if (likely(status == DMA_COMPLETE)) {
		writel(BUF_PART_FULL, host->base + MMC_PRTBUF);
	} else {
		pr_err("%s: DMA error on %s channel\n", mmc_hostname(host->mmc),
			host->data->flags & MMC_DATA_READ ? "rx" : "tx");
		host->data->error = -EIO;
		pxamci_data_done(host, 0);
	}

out_unlock:
	spin_unlock_irqrestore(&host->lock, flags);
}

static irqreturn_t pxamci_detect_irq(int irq, void *devid)
{
	struct pxamci_host *host = mmc_priv(devid);

	mmc_detect_change(devid, msecs_to_jiffies(host->pdata->detect_delay_ms));
	return IRQ_HANDLED;
}

#ifdef CONFIG_OF
static const struct of_device_id pxa_mmc_dt_ids[] = {
        { .compatible = "marvell,pxa-mmc" },
        { }
};

MODULE_DEVICE_TABLE(of, pxa_mmc_dt_ids);

static int pxamci_of_init(struct platform_device *pdev)
{
        struct device_node *np = pdev->dev.of_node;
        struct pxamci_platform_data *pdata;
        u32 tmp;

        if (!np)
                return 0;

        pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
        if (!pdata)
                return -ENOMEM;

	pdata->gpio_card_detect =
		of_get_named_gpio(np, "cd-gpios", 0);
	pdata->gpio_card_ro =
		of_get_named_gpio(np, "wp-gpios", 0);

	/* pxa-mmc specific */
	pdata->gpio_power =
		of_get_named_gpio(np, "pxa-mmc,gpio-power", 0);

	if (of_property_read_u32(np, "pxa-mmc,detect-delay-ms", &tmp) == 0)
		pdata->detect_delay_ms = tmp;

        pdev->dev.platform_data = pdata;

        return 0;
}
#else
static int pxamci_of_init(struct platform_device *pdev)
{
        return 0;
}
#endif

static int pxamci_probe(struct platform_device *pdev)
{
	struct mmc_host *mmc;
	struct pxamci_host *host = NULL;
	struct resource *r, *dmarx, *dmatx;
	struct pxad_param param_rx, param_tx;
	int ret, irq, gpio_cd = -1, gpio_ro = -1, gpio_power = -1;
	dma_cap_mask_t mask;

	ret = pxamci_of_init(pdev);
	if (ret)
		return ret;

	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	irq = platform_get_irq(pdev, 0);
	if (irq < 0)
		return irq;

	mmc = mmc_alloc_host(sizeof(struct pxamci_host), &pdev->dev);
	if (!mmc) {
		ret = -ENOMEM;
		goto out;
	}

	mmc->ops = &pxamci_ops;

	/*
	 * We can do SG-DMA, but we don't because we never know how much
	 * data we successfully wrote to the card.
	 */
	mmc->max_segs = NR_SG;

	/*
	 * Our hardware DMA can handle a maximum of one page per SG entry.
	 */
	mmc->max_seg_size = PAGE_SIZE;

	/*
	 * Block length register is only 10 bits before PXA27x.
	 */
	mmc->max_blk_size = cpu_is_pxa25x() ? 1023 : 2048;

	/*
	 * Block count register is 16 bits.
	 */
	mmc->max_blk_count = 65535;

	host = mmc_priv(mmc);
	host->mmc = mmc;
	host->pdata = pdev->dev.platform_data;
	host->clkrt = CLKRT_OFF;

	host->clk = devm_clk_get(&pdev->dev, NULL);
	if (IS_ERR(host->clk)) {
		ret = PTR_ERR(host->clk);
		host->clk = NULL;
		goto out;
	}

	host->clkrate = clk_get_rate(host->clk);

	/*
	 * Calculate minimum clock rate, rounding up.
	 */
	mmc->f_min = (host->clkrate + 63) / 64;
	mmc->f_max = (mmc_has_26MHz()) ? 26000000 : host->clkrate;

	pxamci_init_ocr(host);

	mmc->caps = 0;
	host->cmdat = 0;
	if (!cpu_is_pxa25x()) {
		mmc->caps |= MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
		host->cmdat |= CMDAT_SDIO_INT_EN;
		if (mmc_has_26MHz())
			mmc->caps |= MMC_CAP_MMC_HIGHSPEED |
				     MMC_CAP_SD_HIGHSPEED;
	}

	spin_lock_init(&host->lock);
	host->res = r;
	host->irq = irq;
	host->imask = MMC_I_MASK_ALL;

	host->base = devm_ioremap_resource(&pdev->dev, r);
	if (IS_ERR(host->base)) {
		ret = PTR_ERR(host->base);
		goto out;
	}

	/*
	 * Ensure that the host controller is shut down, and setup
	 * with our defaults.
	 */
	pxamci_stop_clock(host);
	writel(0, host->base + MMC_SPI);
	writel(64, host->base + MMC_RESTO);
	writel(host->imask, host->base + MMC_I_MASK);

	ret = devm_request_irq(&pdev->dev, host->irq, pxamci_irq, 0,
			       DRIVER_NAME, host);
	if (ret)
		goto out;

	platform_set_drvdata(pdev, mmc);

	if (!pdev->dev.of_node) {
		dmarx = platform_get_resource(pdev, IORESOURCE_DMA, 0);
		dmatx = platform_get_resource(pdev, IORESOURCE_DMA, 1);
		if (!dmarx || !dmatx) {
			ret = -ENXIO;
			goto out;
		}
		param_rx.prio = PXAD_PRIO_LOWEST;
		param_rx.drcmr = dmarx->start;
		param_tx.prio = PXAD_PRIO_LOWEST;
		param_tx.drcmr = dmatx->start;
	}

	dma_cap_zero(mask);
	dma_cap_set(DMA_SLAVE, mask);

	host->dma_chan_rx =
		dma_request_slave_channel_compat(mask, pxad_filter_fn,
						 &param_rx, &pdev->dev, "rx");
	if (host->dma_chan_rx == NULL) {
		dev_err(&pdev->dev, "unable to request rx dma channel\n");
		ret = -ENODEV;
		goto out;
	}

	host->dma_chan_tx =
		dma_request_slave_channel_compat(mask, pxad_filter_fn,
						 &param_tx,  &pdev->dev, "tx");
	if (host->dma_chan_tx == NULL) {
		dev_err(&pdev->dev, "unable to request tx dma channel\n");
		ret = -ENODEV;
		goto out;
	}

	if (host->pdata) {
		gpio_cd = host->pdata->gpio_card_detect;
		gpio_ro = host->pdata->gpio_card_ro;
		gpio_power = host->pdata->gpio_power;
	}
	if (gpio_is_valid(gpio_power)) {
		ret = devm_gpio_request(&pdev->dev, gpio_power,
					"mmc card power");
		if (ret) {
			dev_err(&pdev->dev, "Failed requesting gpio_power %d\n",
				gpio_power);
			goto out;
		}
		gpio_direction_output(gpio_power,
				      host->pdata->gpio_power_invert);
	}
	if (gpio_is_valid(gpio_ro)) {
		ret = mmc_gpio_request_ro(mmc, gpio_ro);
		if (ret) {
			dev_err(&pdev->dev, "Failed requesting gpio_ro %d\n",
				gpio_ro);
			goto out;
		} else {
			mmc->caps2 |= host->pdata->gpio_card_ro_invert ?
				0 : MMC_CAP2_RO_ACTIVE_HIGH;
		}
	}

	if (gpio_is_valid(gpio_cd))
		ret = mmc_gpio_request_cd(mmc, gpio_cd, 0);
	if (ret) {
		dev_err(&pdev->dev, "Failed requesting gpio_cd %d\n", gpio_cd);
		goto out;
	}

	if (host->pdata && host->pdata->init)
		host->pdata->init(&pdev->dev, pxamci_detect_irq, mmc);

	if (gpio_is_valid(gpio_power) && host->pdata->setpower)
		dev_warn(&pdev->dev, "gpio_power and setpower() both defined\n");
	if (gpio_is_valid(gpio_ro) && host->pdata->get_ro)
		dev_warn(&pdev->dev, "gpio_ro and get_ro() both defined\n");

	mmc_add_host(mmc);

	return 0;

out:
	if (host) {
		if (host->dma_chan_rx)
			dma_release_channel(host->dma_chan_rx);
		if (host->dma_chan_tx)
			dma_release_channel(host->dma_chan_tx);
	}
	if (mmc)
		mmc_free_host(mmc);
	return ret;
}

static int pxamci_remove(struct platform_device *pdev)
{
	struct mmc_host *mmc = platform_get_drvdata(pdev);
	int gpio_cd = -1, gpio_ro = -1, gpio_power = -1;

	if (mmc) {
		struct pxamci_host *host = mmc_priv(mmc);

		mmc_remove_host(mmc);

		if (host->pdata) {
			gpio_cd = host->pdata->gpio_card_detect;
			gpio_ro = host->pdata->gpio_card_ro;
			gpio_power = host->pdata->gpio_power;
		}
		if (host->pdata && host->pdata->exit)
			host->pdata->exit(&pdev->dev, mmc);

		pxamci_stop_clock(host);
		writel(TXFIFO_WR_REQ|RXFIFO_RD_REQ|CLK_IS_OFF|STOP_CMD|
		       END_CMD_RES|PRG_DONE|DATA_TRAN_DONE,
		       host->base + MMC_I_MASK);

		dmaengine_terminate_all(host->dma_chan_rx);
		dmaengine_terminate_all(host->dma_chan_tx);
		dma_release_channel(host->dma_chan_rx);
		dma_release_channel(host->dma_chan_tx);

		mmc_free_host(mmc);
	}
	return 0;
}

static struct platform_driver pxamci_driver = {
	.probe		= pxamci_probe,
	.remove		= pxamci_remove,
	.driver		= {
		.name	= DRIVER_NAME,
		.of_match_table = of_match_ptr(pxa_mmc_dt_ids),
	},
};

module_platform_driver(pxamci_driver);

MODULE_DESCRIPTION("PXA Multimedia Card Interface Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:pxa2xx-mci");