mmc: Blackfin SD Host Controller Driver

Add SD host driver for Blackfin BF54x and BF51x.

[akpm@linux-foundation.org: fix layout, c99 warning]
Signed-off-by: Cliff Cai <cliffcai.sh@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 639 insertions, 0 deletions

diff --git a/drivers/mmc/host/bfin_sdh.c b/drivers/mmc/host/bfin_sdh.c
new file mode 100644
index 000000000000..3343a57355cc
--- /dev/null
+++ b/drivers/mmc/host/bfin_sdh.c
@@ -0,0 +1,639 @@
+/*
+ * bfin_sdh.c - Analog Devices Blackfin SDH Controller
+ *
+ * Copyright (C) 2007-2009 Analog Device Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#define DRIVER_NAME	"bfin-sdh"
+
+#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/dma-mapping.h>
+#include <linux/mmc/host.h>
+#include <linux/proc_fs.h>
+
+#include <asm/cacheflush.h>
+#include <asm/dma.h>
+#include <asm/portmux.h>
+#include <asm/bfin_sdh.h>
+
+#if defined(CONFIG_BF51x)
+#define bfin_read_SDH_PWR_CTL		bfin_read_RSI_PWR_CTL
+#define bfin_write_SDH_PWR_CTL		bfin_write_RSI_PWR_CTL
+#define bfin_read_SDH_CLK_CTL		bfin_read_RSI_CLK_CTL
+#define bfin_write_SDH_CLK_CTL		bfin_write_RSI_CLK_CTL
+#define bfin_write_SDH_ARGUMENT		bfin_write_RSI_ARGUMENT
+#define bfin_write_SDH_COMMAND		bfin_write_RSI_COMMAND
+#define bfin_write_SDH_DATA_TIMER	bfin_write_RSI_DATA_TIMER
+#define bfin_read_SDH_RESPONSE0		bfin_read_RSI_RESPONSE0
+#define bfin_read_SDH_RESPONSE1		bfin_read_RSI_RESPONSE1
+#define bfin_read_SDH_RESPONSE2		bfin_read_RSI_RESPONSE2
+#define bfin_read_SDH_RESPONSE3		bfin_read_RSI_RESPONSE3
+#define bfin_write_SDH_DATA_LGTH	bfin_write_RSI_DATA_LGTH
+#define bfin_read_SDH_DATA_CTL		bfin_read_RSI_DATA_CTL
+#define bfin_write_SDH_DATA_CTL		bfin_write_RSI_DATA_CTL
+#define bfin_read_SDH_DATA_CNT		bfin_read_RSI_DATA_CNT
+#define bfin_write_SDH_STATUS_CLR	bfin_write_RSI_STATUS_CLR
+#define bfin_read_SDH_E_STATUS		bfin_read_RSI_E_STATUS
+#define bfin_write_SDH_E_STATUS		bfin_write_RSI_E_STATUS
+#define bfin_read_SDH_STATUS		bfin_read_RSI_STATUS
+#define bfin_write_SDH_MASK0		bfin_write_RSI_MASK0
+#define bfin_read_SDH_CFG		bfin_read_RSI_CFG
+#define bfin_write_SDH_CFG		bfin_write_RSI_CFG
+#endif
+
+struct dma_desc_array {
+	unsigned long	start_addr;
+	unsigned short	cfg;
+	unsigned short	x_count;
+	short		x_modify;
+} __packed;
+
+struct sdh_host {
+	struct mmc_host		*mmc;
+	spinlock_t		lock;
+	struct resource		*res;
+	void __iomem		*base;
+	int			irq;
+	int			stat_irq;
+	int			dma_ch;
+	int			dma_dir;
+	struct dma_desc_array	*sg_cpu;
+	dma_addr_t		sg_dma;
+	int			dma_len;
+
+	unsigned int		imask;
+	unsigned int		power_mode;
+	unsigned int		clk_div;
+
+	struct mmc_request	*mrq;
+	struct mmc_command	*cmd;
+	struct mmc_data		*data;
+};
+
+static struct bfin_sd_host *get_sdh_data(struct platform_device *pdev)
+{
+	return pdev->dev.platform_data;
+}
+
+static void sdh_stop_clock(struct sdh_host *host)
+{
+	bfin_write_SDH_CLK_CTL(bfin_read_SDH_CLK_CTL() & ~CLK_E);
+	SSYNC();
+}
+
+static void sdh_enable_stat_irq(struct sdh_host *host, unsigned int mask)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&host->lock, flags);
+	host->imask |= mask;
+	bfin_write_SDH_MASK0(mask);
+	SSYNC();
+	spin_unlock_irqrestore(&host->lock, flags);
+}
+
+static void sdh_disable_stat_irq(struct sdh_host *host, unsigned int mask)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&host->lock, flags);
+	host->imask &= ~mask;
+	bfin_write_SDH_MASK0(host->imask);
+	SSYNC();
+	spin_unlock_irqrestore(&host->lock, flags);
+}
+
+static int sdh_setup_data(struct sdh_host *host, struct mmc_data *data)
+{
+	unsigned int length;
+	unsigned int data_ctl;
+	unsigned int dma_cfg;
+	struct scatterlist *sg;
+
+	dev_dbg(mmc_dev(host->mmc), "%s enter flags: 0x%x\n", __func__, data->flags);
+	host->data = data;
+	data_ctl = 0;
+	dma_cfg = 0;
+
+	length = data->blksz * data->blocks;
+	bfin_write_SDH_DATA_LGTH(length);
+
+	if (data->flags & MMC_DATA_STREAM)
+		data_ctl |= DTX_MODE;
+
+	if (data->flags & MMC_DATA_READ)
+		data_ctl |= DTX_DIR;
+	/* Only supports power-of-2 block size */
+	if (data->blksz & (data->blksz - 1))
+		return -EINVAL;
+	data_ctl |= ((ffs(data->blksz) - 1) << 4);
+
+	bfin_write_SDH_DATA_CTL(data_ctl);
+
+	bfin_write_SDH_DATA_TIMER(0xFFFF);
+	SSYNC();
+
+	if (data->flags & MMC_DATA_READ) {
+		host->dma_dir = DMA_FROM_DEVICE;
+		dma_cfg |= WNR;
+	} else
+		host->dma_dir = DMA_TO_DEVICE;
+
+	sdh_enable_stat_irq(host, (DAT_CRC_FAIL | DAT_TIME_OUT | DAT_END));
+	host->dma_len = dma_map_sg(mmc_dev(host->mmc), data->sg, data->sg_len, host->dma_dir);
+#if defined(CONFIG_BF54x)
+	dma_cfg |= DMAFLOW_ARRAY | NDSIZE_5 | RESTART | WDSIZE_32 | DMAEN;
+	{
+		int i;
+		for_each_sg(data->sg, sg, host->dma_len, i) {
+			host->sg_cpu[i].start_addr = sg_dma_address(sg);
+			host->sg_cpu[i].cfg = dma_cfg;
+			host->sg_cpu[i].x_count = sg_dma_len(sg) / 4;
+			host->sg_cpu[i].x_modify = 4;
+			dev_dbg(mmc_dev(host->mmc), "%d: start_addr:0x%lx, "
+				"cfg:0x%x, x_count:0x%x, x_modify:0x%x\n",
+				i, host->sg_cpu[i].start_addr,
+				host->sg_cpu[i].cfg, host->sg_cpu[i].x_count,
+				host->sg_cpu[i].x_modify);
+		}
+	}
+	flush_dcache_range((unsigned int)host->sg_cpu,
+		(unsigned int)host->sg_cpu +
+			host->dma_len * sizeof(struct dma_desc_array));
+	/* Set the last descriptor to stop mode */
+	host->sg_cpu[host->dma_len - 1].cfg &= ~(DMAFLOW | NDSIZE);
+	host->sg_cpu[host->dma_len - 1].cfg |= DI_EN;
+
+	set_dma_curr_desc_addr(host->dma_ch, (unsigned long *)host->sg_dma);
+	set_dma_x_count(host->dma_ch, 0);
+	set_dma_x_modify(host->dma_ch, 0);
+	set_dma_config(host->dma_ch, dma_cfg);
+#elif defined(CONFIG_BF51x)
+	/* RSI DMA doesn't work in array mode */
+	dma_cfg |= WDSIZE_32 | DMAEN;
+	set_dma_start_addr(host->dma_ch, sg_dma_address(&data->sg[0]));
+	set_dma_x_count(host->dma_ch, length / 4);
+	set_dma_x_modify(host->dma_ch, 4);
+	set_dma_config(host->dma_ch, dma_cfg);
+#endif
+	bfin_write_SDH_DATA_CTL(bfin_read_SDH_DATA_CTL() | DTX_DMA_E | DTX_E);
+
+	SSYNC();
+
+	dev_dbg(mmc_dev(host->mmc), "%s exit\n", __func__);
+	return 0;
+}
+
+static void sdh_start_cmd(struct sdh_host *host, struct mmc_command *cmd)
+{
+	unsigned int sdh_cmd;
+	unsigned int stat_mask;
+
+	dev_dbg(mmc_dev(host->mmc), "%s enter cmd: 0x%p\n", __func__, cmd);
+	WARN_ON(host->cmd != NULL);
+	host->cmd = cmd;
+
+	sdh_cmd = 0;
+	stat_mask = 0;
+
+	sdh_cmd |= cmd->opcode;
+
+	if (cmd->flags & MMC_RSP_PRESENT) {
+		sdh_cmd |= CMD_RSP;
+		stat_mask |= CMD_RESP_END;
+	} else {
+		stat_mask |= CMD_SENT;
+	}
+
+	if (cmd->flags & MMC_RSP_136)
+		sdh_cmd |= CMD_L_RSP;
+
+	stat_mask |= CMD_CRC_FAIL | CMD_TIME_OUT;
+
+	sdh_enable_stat_irq(host, stat_mask);
+
+	bfin_write_SDH_ARGUMENT(cmd->arg);
+	bfin_write_SDH_COMMAND(sdh_cmd | CMD_E);
+	bfin_write_SDH_CLK_CTL(bfin_read_SDH_CLK_CTL() | CLK_E);
+	SSYNC();
+}
+
+static void sdh_finish_request(struct sdh_host *host, struct mmc_request *mrq)
+{
+	dev_dbg(mmc_dev(host->mmc), "%s enter\n", __func__);
+	host->mrq = NULL;
+	host->cmd = NULL;
+	host->data = NULL;
+	mmc_request_done(host->mmc, mrq);
+}
+
+static int sdh_cmd_done(struct sdh_host *host, unsigned int stat)
+{
+	struct mmc_command *cmd = host->cmd;
+	int ret = 0;
+
+	dev_dbg(mmc_dev(host->mmc), "%s enter cmd: %p\n", __func__, cmd);
+	if (!cmd)
+		return 0;
+
+	host->cmd = NULL;
+
+	if (cmd->flags & MMC_RSP_PRESENT) {
+		cmd->resp[0] = bfin_read_SDH_RESPONSE0();
+		if (cmd->flags & MMC_RSP_136) {
+			cmd->resp[1] = bfin_read_SDH_RESPONSE1();
+			cmd->resp[2] = bfin_read_SDH_RESPONSE2();
+			cmd->resp[3] = bfin_read_SDH_RESPONSE3();
+		}
+	}
+	if (stat & CMD_TIME_OUT)
+		cmd->error = -ETIMEDOUT;
+	else if (stat & CMD_CRC_FAIL && cmd->flags & MMC_RSP_CRC)
+		cmd->error = -EILSEQ;
+
+	sdh_disable_stat_irq(host, (CMD_SENT | CMD_RESP_END | CMD_TIME_OUT | CMD_CRC_FAIL));
+
+	if (host->data && !cmd->error) {
+		if (host->data->flags & MMC_DATA_WRITE) {
+			ret = sdh_setup_data(host, host->data);
+			if (ret)
+				return 0;
+		}
+
+		sdh_enable_stat_irq(host, DAT_END | RX_OVERRUN | TX_UNDERRUN | DAT_TIME_OUT);
+	} else
+		sdh_finish_request(host, host->mrq);
+
+	return 1;
+}
+
+static int sdh_data_done(struct sdh_host *host, unsigned int stat)
+{
+	struct mmc_data *data = host->data;
+
+	dev_dbg(mmc_dev(host->mmc), "%s enter stat: 0x%x\n", __func__, stat);
+	if (!data)
+		return 0;
+
+	disable_dma(host->dma_ch);
+	dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
+		     host->dma_dir);
+
+	if (stat & DAT_TIME_OUT)
+		data->error = -ETIMEDOUT;
+	else if (stat & DAT_CRC_FAIL)
+		data->error = -EILSEQ;
+	else if (stat & (RX_OVERRUN | TX_UNDERRUN))
+		data->error = -EIO;
+
+	if (!data->error)
+		data->bytes_xfered = data->blocks * data->blksz;
+	else
+		data->bytes_xfered = 0;
+
+	sdh_disable_stat_irq(host, DAT_END | DAT_TIME_OUT | DAT_CRC_FAIL | RX_OVERRUN | TX_UNDERRUN);
+	bfin_write_SDH_STATUS_CLR(DAT_END_STAT | DAT_TIMEOUT_STAT | \
+			DAT_CRC_FAIL_STAT | DAT_BLK_END_STAT | RX_OVERRUN | TX_UNDERRUN);
+	bfin_write_SDH_DATA_CTL(0);
+	SSYNC();
+
+	host->data = NULL;
+	if (host->mrq->stop) {
+		sdh_stop_clock(host);
+		sdh_start_cmd(host, host->mrq->stop);
+	} else {
+		sdh_finish_request(host, host->mrq);
+	}
+
+	return 1;
+}
+
+static void sdh_request(struct mmc_host *mmc, struct mmc_request *mrq)
+{
+	struct sdh_host *host = mmc_priv(mmc);
+	int ret = 0;
+
+	dev_dbg(mmc_dev(host->mmc), "%s enter, mrp:%p, cmd:%p\n", __func__, mrq, mrq->cmd);
+	WARN_ON(host->mrq != NULL);
+
+	host->mrq = mrq;
+	host->data = mrq->data;
+
+	if (mrq->data && mrq->data->flags & MMC_DATA_READ) {
+		ret = sdh_setup_data(host, mrq->data);
+		if (ret)
+			return;
+	}
+
+	sdh_start_cmd(host, mrq->cmd);
+}
+
+static void sdh_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+{
+	struct sdh_host *host;
+	unsigned long flags;
+	u16 clk_ctl = 0;
+	u16 pwr_ctl = 0;
+	u16 cfg;
+	host = mmc_priv(mmc);
+
+	spin_lock_irqsave(&host->lock, flags);
+	if (ios->clock) {
+		unsigned long  sys_clk, ios_clk;
+		unsigned char clk_div;
+		ios_clk = 2 * ios->clock;
+		sys_clk = get_sclk();
+		clk_div = sys_clk / ios_clk;
+		if (sys_clk % ios_clk == 0)
+			clk_div -= 1;
+		clk_div = min_t(unsigned char, clk_div, 0xFF);
+		clk_ctl |= clk_div;
+		clk_ctl |= CLK_E;
+		host->clk_div = clk_div;
+	} else
+		sdh_stop_clock(host);
+
+	if (ios->bus_mode == MMC_BUSMODE_OPENDRAIN)
+#ifdef CONFIG_SDH_BFIN_MISSING_CMD_PULLUP_WORKAROUND
+		pwr_ctl |= ROD_CTL;
+#else
+		pwr_ctl |= SD_CMD_OD | ROD_CTL;
+#endif
+
+	if (ios->bus_width == MMC_BUS_WIDTH_4) {
+		cfg = bfin_read_SDH_CFG();
+		cfg &= ~PD_SDDAT3;
+		cfg |= PUP_SDDAT3;
+		/* Enable 4 bit SDIO */
+		cfg |= (SD4E | MWE);
+		bfin_write_SDH_CFG(cfg);
+		clk_ctl |= WIDE_BUS;
+	} else {
+		cfg = bfin_read_SDH_CFG();
+		cfg |= MWE;
+		bfin_write_SDH_CFG(cfg);
+	}
+
+	bfin_write_SDH_CLK_CTL(clk_ctl);
+
+	host->power_mode = ios->power_mode;
+	if (ios->power_mode == MMC_POWER_ON)
+		pwr_ctl |= PWR_ON;
+
+	bfin_write_SDH_PWR_CTL(pwr_ctl);
+	SSYNC();
+
+	spin_unlock_irqrestore(&host->lock, flags);
+
+	dev_dbg(mmc_dev(host->mmc), "SDH: clk_div = 0x%x actual clock:%ld expected clock:%d\n",
+		host->clk_div,
+		host->clk_div ? get_sclk() / (2 * (host->clk_div + 1)) : 0,
+		ios->clock);
+}
+
+static const struct mmc_host_ops sdh_ops = {
+	.request	= sdh_request,
+	.set_ios	= sdh_set_ios,
+};
+
+static irqreturn_t sdh_dma_irq(int irq, void *devid)
+{
+	struct sdh_host *host = devid;
+
+	dev_dbg(mmc_dev(host->mmc), "%s enter, irq_stat: 0x%04x\n", __func__,
+		get_dma_curr_irqstat(host->dma_ch));
+	clear_dma_irqstat(host->dma_ch);
+	SSYNC();
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t sdh_stat_irq(int irq, void *devid)
+{
+	struct sdh_host *host = devid;
+	unsigned int status;
+	int handled = 0;
+
+	dev_dbg(mmc_dev(host->mmc), "%s enter\n", __func__);
+	status = bfin_read_SDH_E_STATUS();
+	if (status & SD_CARD_DET) {
+		mmc_detect_change(host->mmc, 0);
+		bfin_write_SDH_E_STATUS(SD_CARD_DET);
+	}
+	status = bfin_read_SDH_STATUS();
+	if (status & (CMD_SENT | CMD_RESP_END | CMD_TIME_OUT | CMD_CRC_FAIL)) {
+		handled |= sdh_cmd_done(host, status);
+		bfin_write_SDH_STATUS_CLR(CMD_SENT_STAT | CMD_RESP_END_STAT | \
+				CMD_TIMEOUT_STAT | CMD_CRC_FAIL_STAT);
+		SSYNC();
+	}
+
+	status = bfin_read_SDH_STATUS();
+	if (status & (DAT_END | DAT_TIME_OUT | DAT_CRC_FAIL | RX_OVERRUN | TX_UNDERRUN))
+		handled |= sdh_data_done(host, status);
+
+	dev_dbg(mmc_dev(host->mmc), "%s exit\n\n", __func__);
+
+	return IRQ_RETVAL(handled);
+}
+
+static int __devinit sdh_probe(struct platform_device *pdev)
+{
+	struct mmc_host *mmc;
+	struct sdh_host *host;
+	struct bfin_sd_host *drv_data = get_sdh_data(pdev);
+	int ret;
+
+	if (!drv_data) {
+		dev_err(&pdev->dev, "missing platform driver data\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	mmc = mmc_alloc_host(sizeof(*mmc), &pdev->dev);
+	if (!mmc) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	mmc->ops = &sdh_ops;
+	mmc->max_phys_segs = 32;
+	mmc->max_seg_size = 1 << 16;
+	mmc->max_blk_size = 1 << 11;
+	mmc->max_blk_count = 1 << 11;
+	mmc->max_req_size = PAGE_SIZE;
+	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
+	mmc->f_max = get_sclk();
+	mmc->f_min = mmc->f_max >> 9;
+	mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_NEEDS_POLL;
+	host = mmc_priv(mmc);
+	host->mmc = mmc;
+
+	spin_lock_init(&host->lock);
+	host->irq = drv_data->irq_int0;
+	host->dma_ch = drv_data->dma_chan;
+
+	ret = request_dma(host->dma_ch, DRIVER_NAME "DMA");
+	if (ret) {
+		dev_err(&pdev->dev, "unable to request DMA channel\n");
+		goto out1;
+	}
+
+	ret = set_dma_callback(host->dma_ch, sdh_dma_irq, host);
+	if (ret) {
+		dev_err(&pdev->dev, "unable to request DMA irq\n");
+		goto out2;
+	}
+
+	host->sg_cpu = dma_alloc_coherent(&pdev->dev, PAGE_SIZE, &host->sg_dma, GFP_KERNEL);
+	if (host->sg_cpu == NULL) {
+		ret = -ENOMEM;
+		goto out2;
+	}
+
+	platform_set_drvdata(pdev, mmc);
+	mmc_add_host(mmc);
+
+	ret = request_irq(host->irq, sdh_stat_irq, 0, "SDH Status IRQ", host);
+	if (ret) {
+		dev_err(&pdev->dev, "unable to request status irq\n");
+		goto out3;
+	}
+
+	ret = peripheral_request_list(drv_data->pin_req, DRIVER_NAME);
+	if (ret) {
+		dev_err(&pdev->dev, "unable to request peripheral pins\n");
+		goto out4;
+	}
+#if defined(CONFIG_BF54x)
+	/* Secure Digital Host shares DMA with Nand controller */
+	bfin_write_DMAC1_PERIMUX(bfin_read_DMAC1_PERIMUX() | 0x1);
+#endif
+
+	bfin_write_SDH_CFG(bfin_read_SDH_CFG() | CLKS_EN);
+	SSYNC();
+
+	/* Disable card inserting detection pin. set MMC_CAP_NEES_POLL, and
+	 * mmc stack will do the detection.
+	 */
+	bfin_write_SDH_CFG((bfin_read_SDH_CFG() & 0x1F) | (PUP_SDDAT | PUP_SDDAT3));
+	SSYNC();
+
+	return 0;
+
+out4:
+	free_irq(host->irq, host);
+out3:
+	mmc_remove_host(mmc);
+	dma_free_coherent(&pdev->dev, PAGE_SIZE, host->sg_cpu, host->sg_dma);
+out2:
+	free_dma(host->dma_ch);
+out1:
+	mmc_free_host(mmc);
+ out:
+	return ret;
+}
+
+static int __devexit sdh_remove(struct platform_device *pdev)
+{
+	struct mmc_host *mmc = platform_get_drvdata(pdev);
+
+	platform_set_drvdata(pdev, NULL);
+
+	if (mmc) {
+		struct sdh_host *host = mmc_priv(mmc);
+
+		mmc_remove_host(mmc);
+
+		sdh_stop_clock(host);
+		free_irq(host->irq, host);
+		free_dma(host->dma_ch);
+		dma_free_coherent(&pdev->dev, PAGE_SIZE, host->sg_cpu, host->sg_dma);
+
+		mmc_free_host(mmc);
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int sdh_suspend(struct platform_device *dev, pm_message_t state)
+{
+	struct mmc_host *mmc = platform_get_drvdata(dev);
+	struct bfin_sd_host *drv_data = get_sdh_data(dev);
+	int ret = 0;
+
+	if (mmc)
+		ret = mmc_suspend_host(mmc, state);
+
+	bfin_write_SDH_PWR_CTL(bfin_read_SDH_PWR_CTL() & ~PWR_ON);
+	peripheral_free_list(drv_data->pin_req);
+
+	return ret;
+}
+
+static int sdh_resume(struct platform_device *dev)
+{
+	struct mmc_host *mmc = platform_get_drvdata(dev);
+	struct bfin_sd_host *drv_data = get_sdh_data(dev);
+	int ret = 0;
+
+	ret = peripheral_request_list(drv_data->pin_req, DRIVER_NAME);
+	if (ret) {
+		dev_err(&dev->dev, "unable to request peripheral pins\n");
+		return ret;
+	}
+
+	bfin_write_SDH_PWR_CTL(bfin_read_SDH_PWR_CTL() | PWR_ON);
+#if defined(CONFIG_BF54x)
+	/* Secure Digital Host shares DMA with Nand controller */
+	bfin_write_DMAC1_PERIMUX(bfin_read_DMAC1_PERIMUX() | 0x1);
+#endif
+	bfin_write_SDH_CFG(bfin_read_SDH_CFG() | CLKS_EN);
+	SSYNC();
+
+	bfin_write_SDH_CFG((bfin_read_SDH_CFG() & 0x1F) | (PUP_SDDAT | PUP_SDDAT3));
+	SSYNC();
+
+	if (mmc)
+		ret = mmc_resume_host(mmc);
+
+	return ret;
+}
+#else
+# define sdh_suspend NULL
+# define sdh_resume  NULL
+#endif
+
+static struct platform_driver sdh_driver = {
+	.probe   = sdh_probe,
+	.remove  = __devexit_p(sdh_remove),
+	.suspend = sdh_suspend,
+	.resume  = sdh_resume,
+	.driver  = {
+		.name = DRIVER_NAME,
+	},
+};
+
+static int __init sdh_init(void)
+{
+	return platform_driver_register(&sdh_driver);
+}
+module_init(sdh_init);
+
+static void __exit sdh_exit(void)
+{
+	platform_driver_unregister(&sdh_driver);
+}
+module_exit(sdh_exit);
+
+MODULE_DESCRIPTION("Blackfin Secure Digital Host Driver");
+MODULE_AUTHOR("Cliff Cai, Roy Huang");
+MODULE_LICENSE("GPL");