[ARM] 5369/1: omap mmc: Add new omap hsmmc controller for 2430 and 34xx, v3

Add omap hsmmc controller for 2430 and 34xx.

Note that this controller has different registers compared to
the earlier omap MMC controller, so sharing code currently is
not possible.

Various updates and fixes from linux-omap list have been
merged into this patch.

Signed-off-by: Madhusudhan Chikkature<madhu.cr@ti.com>
Acked-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

drivers/mmc/host/Kconfig

@@ -76,6 +76,16 @@ config MMC_OMAP
 
 	  If unsure, say N.
 
+config MMC_OMAP_HS
+	tristate "TI OMAP High Speed Multimedia Card Interface support"
+	depends on ARCH_OMAP2430 || ARCH_OMAP3
+	help
+	  This selects the TI OMAP High Speed Multimedia card Interface.
+	  If you have an OMAP2430 or OMAP3 board with a Multimedia Card slot,
+	  say Y or M here.
+
+	  If unsure, say N.
+
 config MMC_WBSD
 	tristate "Winbond W83L51xD SD/MMC Card Interface support"
 	depends on ISA_DMA_API

drivers/mmc/host/Makefile

@@ -15,6 +15,7 @@ obj-$(CONFIG_MMC_RICOH_MMC)	+= ricoh_mmc.o
 obj-$(CONFIG_MMC_WBSD)		+= wbsd.o
 obj-$(CONFIG_MMC_AU1X)		+= au1xmmc.o
 obj-$(CONFIG_MMC_OMAP)		+= omap.o
+obj-$(CONFIG_MMC_OMAP_HS)	+= omap_hsmmc.o
 obj-$(CONFIG_MMC_AT91)		+= at91_mci.o
 obj-$(CONFIG_MMC_ATMELMCI)	+= atmel-mci.o
 obj-$(CONFIG_MMC_TIFM_SD)	+= tifm_sd.o

drivers/mmc/host/omap_hsmmc.c

+/*
+ * drivers/mmc/host/omap_hsmmc.c
+ *
+ * Driver for OMAP2430/3430 MMC controller.
+ *
+ * Copyright (C) 2007 Texas Instruments.
+ *
+ * Authors:
+ *	Syed Mohammed Khasim	<x0khasim@ti.com>
+ *	Madhusudhan		<madhu.cr@ti.com>
+ *	Mohit Jalori		<mjalori@ti.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/platform_device.h>
+#include <linux/workqueue.h>
+#include <linux/timer.h>
+#include <linux/clk.h>
+#include <linux/mmc/host.h>
+#include <linux/io.h>
+#include <linux/semaphore.h>
+#include <mach/dma.h>
+#include <mach/hardware.h>
+#include <mach/board.h>
+#include <mach/mmc.h>
+#include <mach/cpu.h>
+
+/* OMAP HSMMC Host Controller Registers */
+#define OMAP_HSMMC_SYSCONFIG	0x0010
+#define OMAP_HSMMC_CON		0x002C
+#define OMAP_HSMMC_BLK		0x0104
+#define OMAP_HSMMC_ARG		0x0108
+#define OMAP_HSMMC_CMD		0x010C
+#define OMAP_HSMMC_RSP10	0x0110
+#define OMAP_HSMMC_RSP32	0x0114
+#define OMAP_HSMMC_RSP54	0x0118
+#define OMAP_HSMMC_RSP76	0x011C
+#define OMAP_HSMMC_DATA		0x0120
+#define OMAP_HSMMC_HCTL		0x0128
+#define OMAP_HSMMC_SYSCTL	0x012C
+#define OMAP_HSMMC_STAT		0x0130
+#define OMAP_HSMMC_IE		0x0134
+#define OMAP_HSMMC_ISE		0x0138
+#define OMAP_HSMMC_CAPA		0x0140
+
+#define VS18			(1 << 26)
+#define VS30			(1 << 25)
+#define SDVS18			(0x5 << 9)
+#define SDVS30			(0x6 << 9)
+#define SDVSCLR			0xFFFFF1FF
+#define SDVSDET			0x00000400
+#define AUTOIDLE		0x1
+#define SDBP			(1 << 8)
+#define DTO			0xe
+#define ICE			0x1
+#define ICS			0x2
+#define CEN			(1 << 2)
+#define CLKD_MASK		0x0000FFC0
+#define CLKD_SHIFT		6
+#define DTO_MASK		0x000F0000
+#define DTO_SHIFT		16
+#define INT_EN_MASK		0x307F0033
+#define INIT_STREAM		(1 << 1)
+#define DP_SELECT		(1 << 21)
+#define DDIR			(1 << 4)
+#define DMA_EN			0x1
+#define MSBS			(1 << 5)
+#define BCE			(1 << 1)
+#define FOUR_BIT		(1 << 1)
+#define CC			0x1
+#define TC			0x02
+#define OD			0x1
+#define ERR			(1 << 15)
+#define CMD_TIMEOUT		(1 << 16)
+#define DATA_TIMEOUT		(1 << 20)
+#define CMD_CRC			(1 << 17)
+#define DATA_CRC		(1 << 21)
+#define CARD_ERR		(1 << 28)
+#define STAT_CLEAR		0xFFFFFFFF
+#define INIT_STREAM_CMD		0x00000000
+#define DUAL_VOLT_OCR_BIT	7
+#define SRC			(1 << 25)
+#define SRD			(1 << 26)
+
+/*
+ * FIXME: Most likely all the data using these _DEVID defines should come
+ * from the platform_data, or implemented in controller and slot specific
+ * functions.
+ */
+#define OMAP_MMC1_DEVID		0
+#define OMAP_MMC2_DEVID		1
+
+#define OMAP_MMC_DATADIR_NONE	0
+#define OMAP_MMC_DATADIR_READ	1
+#define OMAP_MMC_DATADIR_WRITE	2
+#define MMC_TIMEOUT_MS		20
+#define OMAP_MMC_MASTER_CLOCK	96000000
+#define DRIVER_NAME		"mmci-omap-hs"
+
+/*
+ * One controller can have multiple slots, like on some omap boards using
+ * omap.c controller driver. Luckily this is not currently done on any known
+ * omap_hsmmc.c device.
+ */
+#define mmc_slot(host)		(host->pdata->slots[host->slot_id])
+
+/*
+ * MMC Host controller read/write API's
+ */
+#define OMAP_HSMMC_READ(base, reg)	\
+	__raw_readl((base) + OMAP_HSMMC_##reg)
+
+#define OMAP_HSMMC_WRITE(base, reg, val) \
+	__raw_writel((val), (base) + OMAP_HSMMC_##reg)
+
+struct mmc_omap_host {
+	struct	device		*dev;
+	struct	mmc_host	*mmc;
+	struct	mmc_request	*mrq;
+	struct	mmc_command	*cmd;
+	struct	mmc_data	*data;
+	struct	clk		*fclk;
+	struct	clk		*iclk;
+	struct	clk		*dbclk;
+	struct	semaphore	sem;
+	struct	work_struct	mmc_carddetect_work;
+	void	__iomem		*base;
+	resource_size_t		mapbase;
+	unsigned int		id;
+	unsigned int		dma_len;
+	unsigned int		dma_dir;
+	unsigned char		bus_mode;
+	unsigned char		datadir;
+	u32			*buffer;
+	u32			bytesleft;
+	int			suspended;
+	int			irq;
+	int			carddetect;
+	int			use_dma, dma_ch;
+	int			initstr;
+	int			slot_id;
+	int			dbclk_enabled;
+	struct	omap_mmc_platform_data	*pdata;
+};
+
+/*
+ * Stop clock to the card
+ */
+static void omap_mmc_stop_clock(struct mmc_omap_host *host)
+{
+	OMAP_HSMMC_WRITE(host->base, SYSCTL,
+		OMAP_HSMMC_READ(host->base, SYSCTL) & ~CEN);
+	if ((OMAP_HSMMC_READ(host->base, SYSCTL) & CEN) != 0x0)
+		dev_dbg(mmc_dev(host->mmc), "MMC Clock is not stoped\n");
+}
+
+/*
+ * Send init stream sequence to card
+ * before sending IDLE command
+ */
+static void send_init_stream(struct mmc_omap_host *host)
+{
+	int reg = 0;
+	unsigned long timeout;
+
+	disable_irq(host->irq);
+	OMAP_HSMMC_WRITE(host->base, CON,
+		OMAP_HSMMC_READ(host->base, CON) | INIT_STREAM);
+	OMAP_HSMMC_WRITE(host->base, CMD, INIT_STREAM_CMD);
+
+	timeout = jiffies + msecs_to_jiffies(MMC_TIMEOUT_MS);
+	while ((reg != CC) && time_before(jiffies, timeout))
+		reg = OMAP_HSMMC_READ(host->base, STAT) & CC;
+
+	OMAP_HSMMC_WRITE(host->base, CON,
+		OMAP_HSMMC_READ(host->base, CON) & ~INIT_STREAM);
+	enable_irq(host->irq);
+}
+
+static inline
+int mmc_omap_cover_is_closed(struct mmc_omap_host *host)
+{
+	int r = 1;
+
+	if (host->pdata->slots[host->slot_id].get_cover_state)
+		r = host->pdata->slots[host->slot_id].get_cover_state(host->dev,
+			host->slot_id);
+	return r;
+}
+
+static ssize_t
+mmc_omap_show_cover_switch(struct device *dev, struct device_attribute *attr,
+			   char *buf)
+{
+	struct mmc_host *mmc = container_of(dev, struct mmc_host, class_dev);
+	struct mmc_omap_host *host = mmc_priv(mmc);
+
+	return sprintf(buf, "%s\n", mmc_omap_cover_is_closed(host) ? "closed" :
+		       "open");
+}
+
+static DEVICE_ATTR(cover_switch, S_IRUGO, mmc_omap_show_cover_switch, NULL);
+
+static ssize_t
+mmc_omap_show_slot_name(struct device *dev, struct device_attribute *attr,
+			char *buf)
+{
+	struct mmc_host *mmc = container_of(dev, struct mmc_host, class_dev);
+	struct mmc_omap_host *host = mmc_priv(mmc);
+	struct omap_mmc_slot_data slot = host->pdata->slots[host->slot_id];
+
+	return sprintf(buf, "slot:%s\n", slot.name);
+}
+
+static DEVICE_ATTR(slot_name, S_IRUGO, mmc_omap_show_slot_name, NULL);
+
+/*
+ * Configure the response type and send the cmd.
+ */
+static void
+mmc_omap_start_command(struct mmc_omap_host *host, struct mmc_command *cmd,
+	struct mmc_data *data)
+{
+	int cmdreg = 0, resptype = 0, cmdtype = 0;
+
+	dev_dbg(mmc_dev(host->mmc), "%s: CMD%d, argument 0x%08x\n",
+		mmc_hostname(host->mmc), cmd->opcode, cmd->arg);
+	host->cmd = cmd;
+
+	/*
+	 * Clear status bits and enable interrupts
+	 */
+	OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
+	OMAP_HSMMC_WRITE(host->base, ISE, INT_EN_MASK);
+	OMAP_HSMMC_WRITE(host->base, IE, INT_EN_MASK);
+
+	if (cmd->flags & MMC_RSP_PRESENT) {
+		if (cmd->flags & MMC_RSP_136)
+			resptype = 1;
+		else
+			resptype = 2;
+	}
+
+	/*
+	 * Unlike OMAP1 controller, the cmdtype does not seem to be based on
+	 * ac, bc, adtc, bcr. Only commands ending an open ended transfer need
+	 * a val of 0x3, rest 0x0.
+	 */
+	if (cmd == host->mrq->stop)
+		cmdtype = 0x3;
+
+	cmdreg = (cmd->opcode << 24) | (resptype << 16) | (cmdtype << 22);
+
+	if (data) {
+		cmdreg |= DP_SELECT | MSBS | BCE;
+		if (data->flags & MMC_DATA_READ)
+			cmdreg |= DDIR;
+		else
+			cmdreg &= ~(DDIR);
+	}
+
+	if (host->use_dma)
+		cmdreg |= DMA_EN;
+
+	OMAP_HSMMC_WRITE(host->base, ARG, cmd->arg);
+	OMAP_HSMMC_WRITE(host->base, CMD, cmdreg);
+}
+
+/*
+ * Notify the transfer complete to MMC core
+ */
+static void
+mmc_omap_xfer_done(struct mmc_omap_host *host, struct mmc_data *data)
+{
+	host->data = NULL;
+
+	if (host->use_dma && host->dma_ch != -1)
+		dma_unmap_sg(mmc_dev(host->mmc), data->sg, host->dma_len,
+			host->dma_dir);
+
+	host->datadir = OMAP_MMC_DATADIR_NONE;
+
+	if (!data->error)
+		data->bytes_xfered += data->blocks * (data->blksz);
+	else
+		data->bytes_xfered = 0;
+
+	if (!data->stop) {
+		host->mrq = NULL;
+		mmc_request_done(host->mmc, data->mrq);
+		return;
+	}
+	mmc_omap_start_command(host, data->stop, NULL);
+}
+
+/*
+ * Notify the core about command completion
+ */
+static void
+mmc_omap_cmd_done(struct mmc_omap_host *host, struct mmc_command *cmd)
+{
+	host->cmd = NULL;
+
+	if (cmd->flags & MMC_RSP_PRESENT) {
+		if (cmd->flags & MMC_RSP_136) {
+			/* response type 2 */
+			cmd->resp[3] = OMAP_HSMMC_READ(host->base, RSP10);
+			cmd->resp[2] = OMAP_HSMMC_READ(host->base, RSP32);
+			cmd->resp[1] = OMAP_HSMMC_READ(host->base, RSP54);
+			cmd->resp[0] = OMAP_HSMMC_READ(host->base, RSP76);
+		} else {
+			/* response types 1, 1b, 3, 4, 5, 6 */
+			cmd->resp[0] = OMAP_HSMMC_READ(host->base, RSP10);
+		}
+	}
+	if (host->data == NULL || cmd->error) {
+		host->mrq = NULL;
+		mmc_request_done(host->mmc, cmd->mrq);
+	}
+}
+
+/*
+ * DMA clean up for command errors
+ */
+static void mmc_dma_cleanup(struct mmc_omap_host *host)
+{
+	host->data->error = -ETIMEDOUT;
+
+	if (host->use_dma && host->dma_ch != -1) {
+		dma_unmap_sg(mmc_dev(host->mmc), host->data->sg, host->dma_len,
+			host->dma_dir);
+		omap_free_dma(host->dma_ch);
+		host->dma_ch = -1;
+		up(&host->sem);
+	}
+	host->data = NULL;
+	host->datadir = OMAP_MMC_DATADIR_NONE;
+}
+
+/*
+ * Readable error output
+ */
+#ifdef CONFIG_MMC_DEBUG
+static void mmc_omap_report_irq(struct mmc_omap_host *host, u32 status)
+{
+	/* --- means reserved bit without definition at documentation */
+	static const char *mmc_omap_status_bits[] = {
+		"CC", "TC", "BGE", "---", "BWR", "BRR", "---", "---", "CIRQ",
+		"OBI", "---", "---", "---", "---", "---", "ERRI", "CTO", "CCRC",
+		"CEB", "CIE", "DTO", "DCRC", "DEB", "---", "ACE", "---",
+		"---", "---", "---", "CERR", "CERR", "BADA", "---", "---", "---"
+	};
+	char res[256];
+	char *buf = res;
+	int len, i;
+
+	len = sprintf(buf, "MMC IRQ 0x%x :", status);
+	buf += len;
+
+	for (i = 0; i < ARRAY_SIZE(mmc_omap_status_bits); i++)
+		if (status & (1 << i)) {
+			len = sprintf(buf, " %s", mmc_omap_status_bits[i]);
+			buf += len;
+		}
+
+	dev_dbg(mmc_dev(host->mmc), "%s\n", res);
+}
+#endif  /* CONFIG_MMC_DEBUG */
+
+
+/*
+ * MMC controller IRQ handler
+ */
+static irqreturn_t mmc_omap_irq(int irq, void *dev_id)
+{
+	struct mmc_omap_host *host = dev_id;
+	struct mmc_data *data;
+	int end_cmd = 0, end_trans = 0, status;
+
+	if (host->cmd == NULL && host->data == NULL) {
+		OMAP_HSMMC_WRITE(host->base, STAT,
+			OMAP_HSMMC_READ(host->base, STAT));
+		return IRQ_HANDLED;
+	}
+
+	data = host->data;
+	status = OMAP_HSMMC_READ(host->base, STAT);
+	dev_dbg(mmc_dev(host->mmc), "IRQ Status is %x\n", status);
+
+	if (status & ERR) {
+#ifdef CONFIG_MMC_DEBUG
+		mmc_omap_report_irq(host, status);
+#endif
+		if ((status & CMD_TIMEOUT) ||
+			(status & CMD_CRC)) {
+			if (host->cmd) {
+				if (status & CMD_TIMEOUT) {
+					OMAP_HSMMC_WRITE(host->base, SYSCTL,
+						OMAP_HSMMC_READ(host->base,
+								SYSCTL) | SRC);
+					while (OMAP_HSMMC_READ(host->base,
+							SYSCTL) & SRC)
+						;
+
+					host->cmd->error = -ETIMEDOUT;
+				} else {
+					host->cmd->error = -EILSEQ;
+				}
+				end_cmd = 1;
+			}
+			if (host->data)
+				mmc_dma_cleanup(host);
+		}
+		if ((status & DATA_TIMEOUT) ||
+			(status & DATA_CRC)) {
+			if (host->data) {
+				if (status & DATA_TIMEOUT)
+					mmc_dma_cleanup(host);
+				else
+					host->data->error = -EILSEQ;
+				OMAP_HSMMC_WRITE(host->base, SYSCTL,
+					OMAP_HSMMC_READ(host->base,
+							SYSCTL) | SRD);
+				while (OMAP_HSMMC_READ(host->base,
+						SYSCTL) & SRD)
+					;
+				end_trans = 1;
+			}
+		}
+		if (status & CARD_ERR) {
+			dev_dbg(mmc_dev(host->mmc),
+				"Ignoring card err CMD%d\n", host->cmd->opcode);
+			if (host->cmd)
+				end_cmd = 1;
+			if (host->data)
+				end_trans = 1;
+		}
+	}
+
+	OMAP_HSMMC_WRITE(host->base, STAT, status);
+
+	if (end_cmd || (status & CC))
+		mmc_omap_cmd_done(host, host->cmd);
+	if (end_trans || (status & TC))
+		mmc_omap_xfer_done(host, data);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * Switch MMC operating voltage
+ */
+static int omap_mmc_switch_opcond(struct mmc_omap_host *host, int vdd)
+{
+	u32 reg_val = 0;
+	int ret;
+
+	/* Disable the clocks */
+	clk_disable(host->fclk);
+	clk_disable(host->iclk);
+	clk_disable(host->dbclk);
+
+	/* Turn the power off */
+	ret = mmc_slot(host).set_power(host->dev, host->slot_id, 0, 0);
+	if (ret != 0)
+		goto err;
+
+	/* Turn the power ON with given VDD 1.8 or 3.0v */
+	ret = mmc_slot(host).set_power(host->dev, host->slot_id, 1, vdd);
+	if (ret != 0)
+		goto err;
+
+	clk_enable(host->fclk);
+	clk_enable(host->iclk);
+	clk_enable(host->dbclk);
+
+	OMAP_HSMMC_WRITE(host->base, HCTL,
+		OMAP_HSMMC_READ(host->base, HCTL) & SDVSCLR);
+	reg_val = OMAP_HSMMC_READ(host->base, HCTL);
+	/*
+	 * If a MMC dual voltage card is detected, the set_ios fn calls
+	 * this fn with VDD bit set for 1.8V. Upon card removal from the
+	 * slot, omap_mmc_set_ios sets the VDD back to 3V on MMC_POWER_OFF.
+	 *
+	 * Only MMC1 supports 3.0V.  MMC2 will not function if SDVS30 is
+	 * set in HCTL.
+	 */
+	if (host->id == OMAP_MMC1_DEVID && (((1 << vdd) == MMC_VDD_32_33) ||
+				((1 << vdd) == MMC_VDD_33_34)))
+		reg_val |= SDVS30;
+	if ((1 << vdd) == MMC_VDD_165_195)
+		reg_val |= SDVS18;
+
+	OMAP_HSMMC_WRITE(host->base, HCTL, reg_val);
+
+	OMAP_HSMMC_WRITE(host->base, HCTL,
+		OMAP_HSMMC_READ(host->base, HCTL) | SDBP);
+
+	return 0;
+err:
+	dev_dbg(mmc_dev(host->mmc), "Unable to switch operating voltage\n");
+	return ret;
+}
+
+/*
+ * Work Item to notify the core about card insertion/removal
+ */
+static void mmc_omap_detect(struct work_struct *work)
+{
+	struct mmc_omap_host *host = container_of(work, struct mmc_omap_host,
+						mmc_carddetect_work);
+
+	sysfs_notify(&host->mmc->class_dev.kobj, NULL, "cover_switch");
+	if (host->carddetect) {
+		mmc_detect_change(host->mmc, (HZ * 200) / 1000);
+	} else {
+		OMAP_HSMMC_WRITE(host->base, SYSCTL,
+			OMAP_HSMMC_READ(host->base, SYSCTL) | SRD);
+		while (OMAP_HSMMC_READ(host->base, SYSCTL) & SRD)
+			;
+
+		mmc_detect_change(host->mmc, (HZ * 50) / 1000);
+	}
+}
+
+/*
+ * ISR for handling card insertion and removal
+ */
+static irqreturn_t omap_mmc_cd_handler(int irq, void *dev_id)
+{
+	struct mmc_omap_host *host = (struct mmc_omap_host *)dev_id;
+
+	host->carddetect = mmc_slot(host).card_detect(irq);
+	schedule_work(&host->mmc_carddetect_work);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * DMA call back function
+ */
+static void mmc_omap_dma_cb(int lch, u16 ch_status, void *data)
+{
+	struct mmc_omap_host *host = data;
+
+	if (ch_status & OMAP2_DMA_MISALIGNED_ERR_IRQ)
+		dev_dbg(mmc_dev(host->mmc), "MISALIGNED_ADRS_ERR\n");
+
+	if (host->dma_ch < 0)
+		return;
+
+	omap_free_dma(host->dma_ch);
+	host->dma_ch = -1;
+	/*
+	 * DMA Callback: run in interrupt context.
+	 * mutex_unlock will through a kernel warning if used.
+	 */
+	up(&host->sem);
+}
+
+/*
+ * Configure dma src and destination parameters
+ */
+static int mmc_omap_config_dma_param(int sync_dir, struct mmc_omap_host *host,
+				struct mmc_data *data)
+{
+	if (sync_dir == 0) {
+		omap_set_dma_dest_params(host->dma_ch, 0,
+			OMAP_DMA_AMODE_CONSTANT,
+			(host->mapbase + OMAP_HSMMC_DATA), 0, 0);
+		omap_set_dma_src_params(host->dma_ch, 0,
+			OMAP_DMA_AMODE_POST_INC,
+			sg_dma_address(&data->sg[0]), 0, 0);
+	} else {
+		omap_set_dma_src_params(host->dma_ch, 0,
+			OMAP_DMA_AMODE_CONSTANT,
+			(host->mapbase + OMAP_HSMMC_DATA), 0, 0);
+		omap_set_dma_dest_params(host->dma_ch, 0,
+			OMAP_DMA_AMODE_POST_INC,
+			sg_dma_address(&data->sg[0]), 0, 0);
+	}
+	return 0;
+}
+/*
+ * Routine to configure and start DMA for the MMC card
+ */
+static int
+mmc_omap_start_dma_transfer(struct mmc_omap_host *host, struct mmc_request *req)
+{
+	int sync_dev, sync_dir = 0;
+	int dma_ch = 0, ret = 0, err = 1;
+	struct mmc_data *data = req->data;
+
+	/*
+	 * If for some reason the DMA transfer is still active,
+	 * we wait for timeout period and free the dma
+	 */
+	if (host->dma_ch != -1) {
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		schedule_timeout(100);
+		if (down_trylock(&host->sem)) {
+			omap_free_dma(host->dma_ch);
+			host->dma_ch = -1;
+			up(&host->sem);
+			return err;
+		}
+	} else {
+		if (down_trylock(&host->sem))
+			return err;
+	}
+
+	if (!(data->flags & MMC_DATA_WRITE)) {
+		host->dma_dir = DMA_FROM_DEVICE;
+		if (host->id == OMAP_MMC1_DEVID)
+			sync_dev = OMAP24XX_DMA_MMC1_RX;
+		else
+			sync_dev = OMAP24XX_DMA_MMC2_RX;
+	} else {
+		host->dma_dir = DMA_TO_DEVICE;
+		if (host->id == OMAP_MMC1_DEVID)
+			sync_dev = OMAP24XX_DMA_MMC1_TX;
+		else
+			sync_dev = OMAP24XX_DMA_MMC2_TX;
+	}
+
+	ret = omap_request_dma(sync_dev, "MMC/SD", mmc_omap_dma_cb,
+			host, &dma_ch);
+	if (ret != 0) {
+		dev_dbg(mmc_dev(host->mmc),
+			"%s: omap_request_dma() failed with %d\n",
+			mmc_hostname(host->mmc), ret);
+		return ret;
+	}
+
+	host->dma_len = dma_map_sg(mmc_dev(host->mmc), data->sg,
+			data->sg_len, host->dma_dir);
+	host->dma_ch = dma_ch;
+
+	if (!(data->flags & MMC_DATA_WRITE))
+		mmc_omap_config_dma_param(1, host, data);
+	else
+		mmc_omap_config_dma_param(0, host, data);
+
+	if ((data->blksz % 4) == 0)
+		omap_set_dma_transfer_params(dma_ch, OMAP_DMA_DATA_TYPE_S32,
+			(data->blksz / 4), data->blocks, OMAP_DMA_SYNC_FRAME,
+			sync_dev, sync_dir);
+	else
+		/* REVISIT: The MMC buffer increments only when MSB is written.
+		 * Return error for blksz which is non multiple of four.
+		 */
+		return -EINVAL;
+
+	omap_start_dma(dma_ch);
+	return 0;
+}
+
+static void set_data_timeout(struct mmc_omap_host *host,
+			     struct mmc_request *req)
+{
+	unsigned int timeout, cycle_ns;
+	uint32_t reg, clkd, dto = 0;
+
+	reg = OMAP_HSMMC_READ(host->base, SYSCTL);
+	clkd = (reg & CLKD_MASK) >> CLKD_SHIFT;
+	if (clkd == 0)
+		clkd = 1;
+
+	cycle_ns = 1000000000 / (clk_get_rate(host->fclk) / clkd);
+	timeout = req->data->timeout_ns / cycle_ns;
+	timeout += req->data->timeout_clks;
+	if (timeout) {
+		while ((timeout & 0x80000000) == 0) {
+			dto += 1;
+			timeout <<= 1;
+		}
+		dto = 31 - dto;
+		timeout <<= 1;
+		if (timeout && dto)
+			dto += 1;
+		if (dto >= 13)
+			dto -= 13;
+		else
+			dto = 0;
+		if (dto > 14)
+			dto = 14;
+	}
+
+	reg &= ~DTO_MASK;
+	reg |= dto << DTO_SHIFT;
+	OMAP_HSMMC_WRITE(host->base, SYSCTL, reg);
+}
+
+/*
+ * Configure block length for MMC/SD cards and initiate the transfer.
+ */
+static int
+mmc_omap_prepare_data(struct mmc_omap_host *host, struct mmc_request *req)
+{
+	int ret;
+	host->data = req->data;
+
+	if (req->data == NULL) {
+		host->datadir = OMAP_MMC_DATADIR_NONE;
+		OMAP_HSMMC_WRITE(host->base, BLK, 0);
+		return 0;
+	}
+
+	OMAP_HSMMC_WRITE(host->base, BLK, (req->data->blksz)
+					| (req->data->blocks << 16));
+	set_data_timeout(host, req);
+
+	host->datadir = (req->data->flags & MMC_DATA_WRITE) ?
+			OMAP_MMC_DATADIR_WRITE : OMAP_MMC_DATADIR_READ;
+
+	if (host->use_dma) {
+		ret = mmc_omap_start_dma_transfer(host, req);
+		if (ret != 0) {
+			dev_dbg(mmc_dev(host->mmc), "MMC start dma failure\n");
+			return ret;
+		}
+	}
+	return 0;
+}
+
+/*
+ * Request function. for read/write operation
+ */
+static void omap_mmc_request(struct mmc_host *mmc, struct mmc_request *req)
+{
+	struct mmc_omap_host *host = mmc_priv(mmc);
+
+	WARN_ON(host->mrq != NULL);
+	host->mrq = req;
+	mmc_omap_prepare_data(host, req);
+	mmc_omap_start_command(host, req->cmd, req->data);
+}
+
+
+/* Routine to configure clock values. Exposed API to core */
+static void omap_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+{
+	struct mmc_omap_host *host = mmc_priv(mmc);
+	u16 dsor = 0;
+	unsigned long regval;
+	unsigned long timeout;
+
+	switch (ios->power_mode) {
+	case MMC_POWER_OFF:
+		mmc_slot(host).set_power(host->dev, host->slot_id, 0, 0);
+		/*
+		 * Reset bus voltage to 3V if it got set to 1.8V earlier.
+		 * REVISIT: If we are able to detect cards after unplugging
+		 * a 1.8V card, this code should not be needed.
+		 */
+		if (!(OMAP_HSMMC_READ(host->base, HCTL) & SDVSDET)) {
+			int vdd = fls(host->mmc->ocr_avail) - 1;
+			if (omap_mmc_switch_opcond(host, vdd) != 0)
+				host->mmc->ios.vdd = vdd;
+		}
+		break;
+	case MMC_POWER_UP:
+		mmc_slot(host).set_power(host->dev, host->slot_id, 1, ios->vdd);
+		break;
+	}
+
+	switch (mmc->ios.bus_width) {
+	case MMC_BUS_WIDTH_4:
+		OMAP_HSMMC_WRITE(host->base, HCTL,
+			OMAP_HSMMC_READ(host->base, HCTL) | FOUR_BIT);
+		break;
+	case MMC_BUS_WIDTH_1:
+		OMAP_HSMMC_WRITE(host->base, HCTL,
+			OMAP_HSMMC_READ(host->base, HCTL) & ~FOUR_BIT);
+		break;
+	}
+
+	if (host->id == OMAP_MMC1_DEVID) {
+		/* Only MMC1 can operate at 3V/1.8V */
+		if ((OMAP_HSMMC_READ(host->base, HCTL) & SDVSDET) &&
+			(ios->vdd == DUAL_VOLT_OCR_BIT)) {
+				/*
+				 * The mmc_select_voltage fn of the core does
+				 * not seem to set the power_mode to
+				 * MMC_POWER_UP upon recalculating the voltage.
+				 * vdd 1.8v.
+				 */
+				if (omap_mmc_switch_opcond(host, ios->vdd) != 0)
+					dev_dbg(mmc_dev(host->mmc),
+						"Switch operation failed\n");
+		}
+	}
+
+	if (ios->clock) {
+		dsor = OMAP_MMC_MASTER_CLOCK / ios->clock;
+		if (dsor < 1)
+			dsor = 1;
+
+		if (OMAP_MMC_MASTER_CLOCK / dsor > ios->clock)
+			dsor++;
+
+		if (dsor > 250)
+			dsor = 250;
+	}
+	omap_mmc_stop_clock(host);
+	regval = OMAP_HSMMC_READ(host->base, SYSCTL);
+	regval = regval & ~(CLKD_MASK);
+	regval = regval | (dsor << 6) | (DTO << 16);
+	OMAP_HSMMC_WRITE(host->base, SYSCTL, regval);
+	OMAP_HSMMC_WRITE(host->base, SYSCTL,
+		OMAP_HSMMC_READ(host->base, SYSCTL) | ICE);
+
+	/* Wait till the ICS bit is set */
+	timeout = jiffies + msecs_to_jiffies(MMC_TIMEOUT_MS);
+	while ((OMAP_HSMMC_READ(host->base, SYSCTL) & ICS) != 0x2
+		&& time_before(jiffies, timeout))
+		msleep(1);
+
+	OMAP_HSMMC_WRITE(host->base, SYSCTL,
+		OMAP_HSMMC_READ(host->base, SYSCTL) | CEN);
+
+	if (ios->power_mode == MMC_POWER_ON)
+		send_init_stream(host);
+
+	if (ios->bus_mode == MMC_BUSMODE_OPENDRAIN)
+		OMAP_HSMMC_WRITE(host->base, CON,
+				OMAP_HSMMC_READ(host->base, CON) | OD);
+}
+
+static int omap_hsmmc_get_cd(struct mmc_host *mmc)
+{
+	struct mmc_omap_host *host = mmc_priv(mmc);
+	struct omap_mmc_platform_data *pdata = host->pdata;
+
+	if (!pdata->slots[0].card_detect)
+		return -ENOSYS;
+	return pdata->slots[0].card_detect(pdata->slots[0].card_detect_irq);
+}
+
+static int omap_hsmmc_get_ro(struct mmc_host *mmc)
+{
+	struct mmc_omap_host *host = mmc_priv(mmc);
+	struct omap_mmc_platform_data *pdata = host->pdata;
+
+	if (!pdata->slots[0].get_ro)
+		return -ENOSYS;
+	return pdata->slots[0].get_ro(host->dev, 0);
+}
+
+static struct mmc_host_ops mmc_omap_ops = {
+	.request = omap_mmc_request,
+	.set_ios = omap_mmc_set_ios,
+	.get_cd = omap_hsmmc_get_cd,
+	.get_ro = omap_hsmmc_get_ro,
+	/* NYET -- enable_sdio_irq */
+};
+
+static int __init omap_mmc_probe(struct platform_device *pdev)
+{
+	struct omap_mmc_platform_data *pdata = pdev->dev.platform_data;
+	struct mmc_host *mmc;
+	struct mmc_omap_host *host = NULL;
+	struct resource *res;
+	int ret = 0, irq;
+	u32 hctl, capa;
+
+	if (pdata == NULL) {
+		dev_err(&pdev->dev, "Platform Data is missing\n");
+		return -ENXIO;
+	}
+
+	if (pdata->nr_slots == 0) {
+		dev_err(&pdev->dev, "No Slots\n");
+		return -ENXIO;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	irq = platform_get_irq(pdev, 0);
+	if (res == NULL || irq < 0)
+		return -ENXIO;
+
+	res = request_mem_region(res->start, res->end - res->start + 1,
+							pdev->name);
+	if (res == NULL)
+		return -EBUSY;
+
+	mmc = mmc_alloc_host(sizeof(struct mmc_omap_host), &pdev->dev);
+	if (!mmc) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	host		= mmc_priv(mmc);
+	host->mmc	= mmc;
+	host->pdata	= pdata;
+	host->dev	= &pdev->dev;
+	host->use_dma	= 1;
+	host->dev->dma_mask = &pdata->dma_mask;
+	host->dma_ch	= -1;
+	host->irq	= irq;
+	host->id	= pdev->id;
+	host->slot_id	= 0;
+	host->mapbase	= res->start;
+	host->base	= ioremap(host->mapbase, SZ_4K);
+
+	platform_set_drvdata(pdev, host);
+	INIT_WORK(&host->mmc_carddetect_work, mmc_omap_detect);
+
+	mmc->ops	= &mmc_omap_ops;
+	mmc->f_min	= 400000;
+	mmc->f_max	= 52000000;
+
+	sema_init(&host->sem, 1);
+
+	host->iclk = clk_get(&pdev->dev, "mmchs_ick");
+	if (IS_ERR(host->iclk)) {
+		ret = PTR_ERR(host->iclk);
+		host->iclk = NULL;
+		goto err1;
+	}
+	host->fclk = clk_get(&pdev->dev, "mmchs_fck");
+	if (IS_ERR(host->fclk)) {
+		ret = PTR_ERR(host->fclk);
+		host->fclk = NULL;
+		clk_put(host->iclk);
+		goto err1;
+	}
+
+	if (clk_enable(host->fclk) != 0) {
+		clk_put(host->iclk);
+		clk_put(host->fclk);
+		goto err1;
+	}
+
+	if (clk_enable(host->iclk) != 0) {
+		clk_disable(host->fclk);
+		clk_put(host->iclk);
+		clk_put(host->fclk);
+		goto err1;
+	}
+
+	host->dbclk = clk_get(&pdev->dev, "mmchsdb_fck");
+	/*
+	 * MMC can still work without debounce clock.
+	 */
+	if (IS_ERR(host->dbclk))
+		dev_warn(mmc_dev(host->mmc), "Failed to get debounce clock\n");
+	else
+		if (clk_enable(host->dbclk) != 0)
+			dev_dbg(mmc_dev(host->mmc), "Enabling debounce"
+							" clk failed\n");
+		else
+			host->dbclk_enabled = 1;
+
+#ifdef CONFIG_MMC_BLOCK_BOUNCE
+	mmc->max_phys_segs = 1;
+	mmc->max_hw_segs = 1;
+#endif
+	mmc->max_blk_size = 512;       /* Block Length at max can be 1024 */
+	mmc->max_blk_count = 0xFFFF;    /* No. of Blocks is 16 bits */
+	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
+	mmc->max_seg_size = mmc->max_req_size;
+
+	mmc->ocr_avail = mmc_slot(host).ocr_mask;
+	mmc->caps |= MMC_CAP_MMC_HIGHSPEED | MMC_CAP_SD_HIGHSPEED;
+
+	if (pdata->slots[host->slot_id].wires >= 4)
+		mmc->caps |= MMC_CAP_4_BIT_DATA;
+
+	/* Only MMC1 supports 3.0V */
+	if (host->id == OMAP_MMC1_DEVID) {
+		hctl = SDVS30;
+		capa = VS30 | VS18;
+	} else {
+		hctl = SDVS18;
+		capa = VS18;
+	}
+
+	OMAP_HSMMC_WRITE(host->base, HCTL,
+			OMAP_HSMMC_READ(host->base, HCTL) | hctl);
+
+	OMAP_HSMMC_WRITE(host->base, CAPA,
+			OMAP_HSMMC_READ(host->base, CAPA) | capa);
+
+	/* Set the controller to AUTO IDLE mode */
+	OMAP_HSMMC_WRITE(host->base, SYSCONFIG,
+			OMAP_HSMMC_READ(host->base, SYSCONFIG) | AUTOIDLE);
+
+	/* Set SD bus power bit */
+	OMAP_HSMMC_WRITE(host->base, HCTL,
+			OMAP_HSMMC_READ(host->base, HCTL) | SDBP);
+
+	/* Request IRQ for MMC operations */
+	ret = request_irq(host->irq, mmc_omap_irq, IRQF_DISABLED,
+			mmc_hostname(mmc), host);
+	if (ret) {
+		dev_dbg(mmc_dev(host->mmc), "Unable to grab HSMMC IRQ\n");
+		goto err_irq;
+	}
+
+	if (pdata->init != NULL) {
+		if (pdata->init(&pdev->dev) != 0) {
+			dev_dbg(mmc_dev(host->mmc),
+				"Unable to configure MMC IRQs\n");
+			goto err_irq_cd_init;
+		}
+	}
+
+	/* Request IRQ for card detect */
+	if ((mmc_slot(host).card_detect_irq) && (mmc_slot(host).card_detect)) {
+		ret = request_irq(mmc_slot(host).card_detect_irq,
+				  omap_mmc_cd_handler,
+				  IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING
+					  | IRQF_DISABLED,
+				  mmc_hostname(mmc), host);
+		if (ret) {
+			dev_dbg(mmc_dev(host->mmc),
+				"Unable to grab MMC CD IRQ\n");
+			goto err_irq_cd;
+		}
+	}
+
+	OMAP_HSMMC_WRITE(host->base, ISE, INT_EN_MASK);
+	OMAP_HSMMC_WRITE(host->base, IE, INT_EN_MASK);
+
+	mmc_add_host(mmc);
+
+	if (host->pdata->slots[host->slot_id].name != NULL) {
+		ret = device_create_file(&mmc->class_dev, &dev_attr_slot_name);
+		if (ret < 0)
+			goto err_slot_name;
+	}
+	if (mmc_slot(host).card_detect_irq && mmc_slot(host).card_detect &&
+			host->pdata->slots[host->slot_id].get_cover_state) {
+		ret = device_create_file(&mmc->class_dev,
+					&dev_attr_cover_switch);
+		if (ret < 0)
+			goto err_cover_switch;
+	}
+
+	return 0;
+
+err_cover_switch:
+	device_remove_file(&mmc->class_dev, &dev_attr_cover_switch);
+err_slot_name:
+	mmc_remove_host(mmc);
+err_irq_cd:
+	free_irq(mmc_slot(host).card_detect_irq, host);
+err_irq_cd_init:
+	free_irq(host->irq, host);
+err_irq:
+	clk_disable(host->fclk);
+	clk_disable(host->iclk);
+	clk_put(host->fclk);
+	clk_put(host->iclk);
+	if (host->dbclk_enabled) {
+		clk_disable(host->dbclk);
+		clk_put(host->dbclk);
+	}
+
+err1:
+	iounmap(host->base);
+err:
+	dev_dbg(mmc_dev(host->mmc), "Probe Failed\n");
+	release_mem_region(res->start, res->end - res->start + 1);
+	if (host)
+		mmc_free_host(mmc);
+	return ret;
+}
+
+static int omap_mmc_remove(struct platform_device *pdev)
+{
+	struct mmc_omap_host *host = platform_get_drvdata(pdev);
+	struct resource *res;
+
+	if (host) {
+		mmc_remove_host(host->mmc);
+		if (host->pdata->cleanup)
+			host->pdata->cleanup(&pdev->dev);
+		free_irq(host->irq, host);
+		if (mmc_slot(host).card_detect_irq)
+			free_irq(mmc_slot(host).card_detect_irq, host);
+		flush_scheduled_work();
+
+		clk_disable(host->fclk);
+		clk_disable(host->iclk);
+		clk_put(host->fclk);
+		clk_put(host->iclk);
+		if (host->dbclk_enabled) {
+			clk_disable(host->dbclk);
+			clk_put(host->dbclk);
+		}
+
+		mmc_free_host(host->mmc);
+		iounmap(host->base);
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (res)
+		release_mem_region(res->start, res->end - res->start + 1);
+	platform_set_drvdata(pdev, NULL);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int omap_mmc_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	int ret = 0;
+	struct mmc_omap_host *host = platform_get_drvdata(pdev);
+
+	if (host && host->suspended)
+		return 0;
+
+	if (host) {
+		ret = mmc_suspend_host(host->mmc, state);
+		if (ret == 0) {
+			host->suspended = 1;
+
+			OMAP_HSMMC_WRITE(host->base, ISE, 0);
+			OMAP_HSMMC_WRITE(host->base, IE, 0);
+
+			if (host->pdata->suspend) {
+				ret = host->pdata->suspend(&pdev->dev,
+								host->slot_id);
+				if (ret)
+					dev_dbg(mmc_dev(host->mmc),
+						"Unable to handle MMC board"
+						" level suspend\n");
+			}
+
+			if (!(OMAP_HSMMC_READ(host->base, HCTL) & SDVSDET)) {
+				OMAP_HSMMC_WRITE(host->base, HCTL,
+					OMAP_HSMMC_READ(host->base, HCTL)
+					& SDVSCLR);
+				OMAP_HSMMC_WRITE(host->base, HCTL,
+					OMAP_HSMMC_READ(host->base, HCTL)
+					| SDVS30);
+				OMAP_HSMMC_WRITE(host->base, HCTL,
+					OMAP_HSMMC_READ(host->base, HCTL)
+					| SDBP);
+			}
+
+			clk_disable(host->fclk);
+			clk_disable(host->iclk);
+			clk_disable(host->dbclk);
+		}
+
+	}
+	return ret;
+}
+
+/* Routine to resume the MMC device */
+static int omap_mmc_resume(struct platform_device *pdev)
+{
+	int ret = 0;
+	struct mmc_omap_host *host = platform_get_drvdata(pdev);
+
+	if (host && !host->suspended)
+		return 0;
+
+	if (host) {
+
+		ret = clk_enable(host->fclk);
+		if (ret)
+			goto clk_en_err;
+
+		ret = clk_enable(host->iclk);
+		if (ret) {
+			clk_disable(host->fclk);
+			clk_put(host->fclk);
+			goto clk_en_err;
+		}
+
+		if (clk_enable(host->dbclk) != 0)
+			dev_dbg(mmc_dev(host->mmc),
+					"Enabling debounce clk failed\n");
+
+		if (host->pdata->resume) {
+			ret = host->pdata->resume(&pdev->dev, host->slot_id);
+			if (ret)
+				dev_dbg(mmc_dev(host->mmc),
+					"Unmask interrupt failed\n");
+		}
+
+		/* Notify the core to resume the host */
+		ret = mmc_resume_host(host->mmc);
+		if (ret == 0)
+			host->suspended = 0;
+	}
+
+	return ret;
+
+clk_en_err:
+	dev_dbg(mmc_dev(host->mmc),
+		"Failed to enable MMC clocks during resume\n");
+	return ret;
+}
+
+#else
+#define omap_mmc_suspend	NULL
+#define omap_mmc_resume		NULL
+#endif
+
+static struct platform_driver omap_mmc_driver = {
+	.probe		= omap_mmc_probe,
+	.remove		= omap_mmc_remove,
+	.suspend	= omap_mmc_suspend,
+	.resume		= omap_mmc_resume,
+	.driver		= {
+		.name = DRIVER_NAME,
+		.owner = THIS_MODULE,
+	},
+};
+
+static int __init omap_mmc_init(void)
+{
+	/* Register the MMC driver */
+	return platform_driver_register(&omap_mmc_driver);
+}
+
+static void __exit omap_mmc_cleanup(void)
+{
+	/* Unregister MMC driver */
+	platform_driver_unregister(&omap_mmc_driver);
+}
+
+module_init(omap_mmc_init);
+module_exit(omap_mmc_cleanup);
+
+MODULE_DESCRIPTION("OMAP High Speed Multimedia Card driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRIVER_NAME);
+MODULE_AUTHOR("Texas Instruments Inc");