Re: [RESEND PATCH] dw_mmc: Add Synopsys DesignWare mmc host driver.

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, Dec 06, 2010 at 03:53:10PM +0000, Will Newton wrote:
> This adds the mmc host driver for the Synopsys DesignWare mmc
> host controller, found in a number of embedded SoC designs.
> 
> Signed-off-by: Will Newton <will.newton@xxxxxxxxxx>

Comments below..

> ---
>  drivers/mmc/host/Kconfig   |   15 +
>  drivers/mmc/host/Makefile  |    1 +
>  drivers/mmc/host/dw_mmc.c  | 1810 ++++++++++++++++++++++++++++++++++++++++++++
>  drivers/mmc/host/dw_mmc.h  |  155 ++++
>  include/linux/mmc/dw_mmc.h |  149 ++++
>  5 files changed, 2130 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/mmc/host/dw_mmc.c
>  create mode 100644 drivers/mmc/host/dw_mmc.h
>  create mode 100644 include/linux/mmc/dw_mmc.h
> 
> Resending, hopefully this time the patch will make it to the linux-mmc list.
> 
> diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
> index f8fa9ef..c99d2c6 100644
> --- a/drivers/mmc/host/Kconfig
> +++ b/drivers/mmc/host/Kconfig
> @@ -469,6 +469,21 @@ config SDH_BFIN_MISSING_CMD_PULLUP_WORKAROUND
>  	help
>  	  If you say yes here SD-Cards may work on the EZkit.
> 
> +config MMC_DW
> +	tristate "Synopsys DesignWare Memory Card Interface"
> +	help
> +	  This selects support for the Synopsys DesignWare Mobile Storage IP
> +	  block, this provides host support for SD and MMC interfaces, in both
> +	  PIO and external DMA modes.
> +
> +config MMC_DW_IDMAC
> +	depends on MMC_DW
> +	bool "Internal DMAC interface"
> +	help
> +	  This selects support for the internal DMAC block within the Synopsys
> +	  Designware Mobile Storage IP block. This disables the external DMA
> +	  interface.
> +
>  config MMC_SH_MMCIF
>  	tristate "SuperH Internal MMCIF support"
>  	depends on MMC_BLOCK && (SUPERH || ARCH_SHMOBILE)
> diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
> index d91364d..a5d1cb2 100644
> --- a/drivers/mmc/host/Makefile
> +++ b/drivers/mmc/host/Makefile
> @@ -31,6 +31,7 @@ obj-$(CONFIG_MMC_TMIO)		+= tmio_mmc.o
>  obj-$(CONFIG_MMC_CB710)	+= cb710-mmc.o
>  obj-$(CONFIG_MMC_VIA_SDMMC)	+= via-sdmmc.o
>  obj-$(CONFIG_SDH_BFIN)		+= bfin_sdh.o
> +obj-$(CONFIG_MMC_DW)		+= dw_mmc.o
>  obj-$(CONFIG_MMC_SH_MMCIF)	+= sh_mmcif.o
>  obj-$(CONFIG_MMC_JZ4740)	+= jz4740_mmc.o
>  obj-$(CONFIG_MMC_USHC)		+= ushc.o
> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
> new file mode 100644
> index 0000000..fa90b44
> --- /dev/null
> +++ b/drivers/mmc/host/dw_mmc.c
> @@ -0,0 +1,1810 @@
> +/*
> + * Synopsys DesignWare Multimedia Card Interface driver
> + *  (Based on NXP driver for lpc 31xx)
> + *
> + * Copyright (C) 2009 NXP Semiconductors
> + * Copyright (C) 2009, 2010 Imagination Technologies Ltd.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
> + *
> + */
> +
> +#include <linux/blkdev.h>
> +#include <linux/clk.h>
> +#include <linux/debugfs.h>
> +#include <linux/device.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/err.h>
> +#include <linux/init.h>
> +#include <linux/interrupt.h>
> +#include <linux/ioport.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/scatterlist.h>
> +#include <linux/seq_file.h>
> +#include <linux/slab.h>
> +#include <linux/stat.h>
> +#include <linux/delay.h>
> +#include <linux/irq.h>
> +#include <linux/mmc/host.h>
> +#include <linux/mmc/mmc.h>
> +#include <linux/mmc/dw_mmc.h>
> +#include <linux/bitops.h>
> +
> +#include "dw_mmc.h"
> +
> +/* Common flag combinations */
> +#define DW_MCI_DATA_ERROR_FLAGS	(SDMMC_INT_DTO | SDMMC_INT_DCRC | \
> +				 SDMMC_INT_HTO | SDMMC_INT_SBE  | \
> +				 SDMMC_INT_EBE)
> +#define DW_MCI_CMD_ERROR_FLAGS	(SDMMC_INT_RTO | SDMMC_INT_RCRC | \
> +				 SDMMC_INT_RESP_ERR)
> +#define DW_MCI_ERROR_FLAGS	(DW_MCI_DATA_ERROR_FLAGS | \
> +				 DW_MCI_CMD_ERROR_FLAGS  | SDMMC_INT_HLE)
> +#define DW_MCI_SEND_STATUS	1
> +#define DW_MCI_RECV_STATUS	2
> +#define DW_MCI_DMA_THRESHOLD	16
> +
> +#ifdef CONFIG_MMC_DW_IDMAC
> +struct idmac_desc {
> +	u32		des0;	/* Control Descriptor */
> +#define IDMAC_DES0_DIC	BIT(1)
> +#define IDMAC_DES0_LD	BIT(2)
> +#define IDMAC_DES0_FD	BIT(3)
> +#define IDMAC_DES0_CH	BIT(4)
> +#define IDMAC_DES0_ER	BIT(5)
> +#define IDMAC_DES0_CES	BIT(30)
> +#define IDMAC_DES0_OWN	BIT(31)
> +
> +	u32		des1;	/* Buffer sizes */
> +#define IDMAC_SET_BUFFER1_SIZE(d, s) \
> +	((d)->des1 = ((d)->des1 & 0x03ffc000) | ((s) & 0x3fff))
> +
> +	u32		des2;	/* buffer 1 physical address */
> +
> +	u32		des3;	/* buffer 2 physical address */
> +};
> +#endif /* CONFIG_MMC_DW_IDMAC */
> +
> +struct dw_mci_slot {
> +	struct mmc_host		*mmc;
> +	struct dw_mci		*host;
> +
> +	u32			ctype;
> +
> +	struct mmc_request	*mrq;
> +	struct list_head	queue_node;
> +
> +	unsigned int		clock;
> +	unsigned long		flags;
> +#define DW_MMC_CARD_PRESENT	0
> +#define DW_MMC_CARD_NEED_INIT	1
> +	int			id;
> +	int			last_detect_state;
> +};
> +
> +#if defined(CONFIG_DEBUG_FS)
> +/*
> + * The debugfs stuff below is mostly optimized away when
> + * CONFIG_DEBUG_FS is not set.
> + */
> +static int dw_mci_req_show(struct seq_file *s, void *v)
> +{
> +	struct dw_mci_slot *slot = s->private;
> +	struct mmc_request *mrq;
> +	struct mmc_command *cmd;
> +	struct mmc_command *stop;
> +	struct mmc_data	*data;
> +
> +	/* Make sure we get a consistent snapshot */
> +	spin_lock_bh(&slot->host->lock);
> +	mrq = slot->mrq;
> +
> +	if (mrq) {
> +		cmd = mrq->cmd;
> +		data = mrq->data;
> +		stop = mrq->stop;
> +
> +		if (cmd)
> +			seq_printf(s,
> +				"CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n",
> +				cmd->opcode, cmd->arg, cmd->flags,
> +				cmd->resp[0], cmd->resp[1], cmd->resp[2],
> +				cmd->resp[2], cmd->error);
> +		if (data)
> +			seq_printf(s, "DATA %u / %u * %u flg %x err %d\n",
> +				data->bytes_xfered, data->blocks,
> +				data->blksz, data->flags, data->error);
> +		if (stop)
> +			seq_printf(s,
> +				"CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n",
> +				stop->opcode, stop->arg, stop->flags,
> +				stop->resp[0], stop->resp[1], stop->resp[2],
> +				stop->resp[2], stop->error);
> +	}
> +
> +	spin_unlock_bh(&slot->host->lock);
> +
> +	return 0;
> +}
> +
> +static int dw_mci_req_open(struct inode *inode, struct file *file)
> +{
> +	return single_open(file, dw_mci_req_show, inode->i_private);
> +}
> +
> +static const struct file_operations dw_mci_req_fops = {
> +	.owner		= THIS_MODULE,
> +	.open		= dw_mci_req_open,
> +	.read		= seq_read,
> +	.llseek		= seq_lseek,
> +	.release	= single_release,
> +};
> +
> +static int dw_mci_regs_show(struct seq_file *s, void *v)
> +{
> +	seq_printf(s, "STATUS:\t0x%08x\n", SDMMC_STATUS);
> +	seq_printf(s, "RINTSTS:\t0x%08x\n", SDMMC_RINTSTS);
> +	seq_printf(s, "CMD:\t0x%08x\n", SDMMC_CMD);
> +	seq_printf(s, "CTRL:\t0x%08x\n", SDMMC_CTRL);
> +	seq_printf(s, "INTMASK:\t0x%08x\n", SDMMC_INTMASK);
> +	seq_printf(s, "CLKENA:\t0x%08x\n", SDMMC_CLKENA);
> +
> +	return 0;
> +}
> +
> +static int dw_mci_regs_open(struct inode *inode, struct file *file)
> +{
> +	return single_open(file, dw_mci_regs_show, inode->i_private);
> +}
> +
> +static const struct file_operations dw_mci_regs_fops = {
> +	.owner		= THIS_MODULE,
> +	.open		= dw_mci_regs_open,
> +	.read		= seq_read,
> +	.llseek		= seq_lseek,
> +	.release	= single_release,
> +};
> +
> +static void dw_mci_init_debugfs(struct dw_mci_slot *slot)
> +{
> +	struct mmc_host	*mmc = slot->mmc;
> +	struct dw_mci *host = slot->host;
> +	struct dentry *root;
> +	struct dentry *node;
> +
> +	root = mmc->debugfs_root;
> +	if (!root)
> +		return;
> +
> +	node = debugfs_create_file("regs", S_IRUSR, root, host,
> +			&dw_mci_regs_fops);
> +	if (IS_ERR(node))
> +		return;

Should this be a goto err instead of return? I'm guessing this is
meant to catch -ENODEV being returned when debugfs is not enabled in
the kernel, but if we've compiled this code with CONFIG_DEBUG_FS then
we probably want to know when this call fails.

> +	if (!node)
> +		goto err;
> +
> +	node = debugfs_create_file("req", S_IRUSR, root, slot,
> +			&dw_mci_req_fops);
> +	if (!node)
> +		goto err;
> +
> +	node = debugfs_create_u32("state", S_IRUSR, root, (u32 *)&host->state);
> +	if (!node)
> +		goto err;
> +
> +	node = debugfs_create_x32("pending_events", S_IRUSR, root,
> +				     (u32 *)&host->pending_events);
> +	if (!node)
> +		goto err;
> +
> +	node = debugfs_create_x32("completed_events", S_IRUSR, root,
> +				     (u32 *)&host->completed_events);
> +	if (!node)
> +		goto err;
> +
> +	return;
> +
> +err:
> +	dev_err(&mmc->class_dev, "failed to initialize debugfs for slot\n");
> +}
> +#endif /* defined(CONFIG_DEBUG_FS) */
> +
> +static void dw_mci_set_timeout(struct dw_mci *host)
> +{
> +	mci_writel(host, TMOUT, 0xffffffff); /* timeout (maximum) */
> +}
> +

Could do with an explicit 'inline'? Especially as it only has one
callsite.

> +static u32 dw_mci_prepare_command(struct mmc_host *mmc,
> +				  struct mmc_command *cmd)
> +{
> +	struct mmc_data	*data;
> +	u32 cmdr;
> +	cmd->error = -EINPROGRESS;
> +
> +	cmdr = cmd->opcode;
> +
> +	if (cmdr == MMC_STOP_TRANSMISSION)
> +		cmdr |= SDMMC_CMD_STOP;
> +	else
> +		cmdr |= SDMMC_CMD_PRV_DAT_WAIT;
> +
> +	if (cmd->flags & MMC_RSP_PRESENT) {
> +		cmdr |= SDMMC_CMD_RESP_EXP;
> +		/* expect the respond, need to set this bit */
> +		if (cmd->flags & MMC_RSP_136)
> +			cmdr |= SDMMC_CMD_RESP_LONG; /* expect long respond */
> +	}
> +
> +	if (cmd->flags & MMC_RSP_CRC)
> +		cmdr |= SDMMC_CMD_RESP_CRC;
> +
> +	data = cmd->data;
> +	if (data) {
> +		cmdr |= SDMMC_CMD_DAT_EXP;
> +		if (data->flags & MMC_DATA_STREAM)
> +			cmdr |= SDMMC_CMD_STRM_MODE; /*  set stream mode */
> +		if (data->flags & MMC_DATA_WRITE)
> +			cmdr |= SDMMC_CMD_DAT_WR;
> +	}
> +
> +	return cmdr;
> +}
> +
> +static void dw_mci_start_command(struct dw_mci *host,
> +				 struct mmc_command *cmd, u32 cmd_flags)
> +{
> +	host->cmd = cmd;
> +	dev_vdbg(&host->pdev->dev,
> +			"start command: ARGR=0x%08x CMDR=0x%08x\n",
> +			cmd->arg, cmd_flags);
> +
> +	/* write to CMDARG register */
> +	mci_writel(host, CMDARG, cmd->arg);
> +	wmb();
> +
> +	/* write to CMD register */
> +	mci_writel(host, CMD, cmd_flags | SDMMC_CMD_START);
> +}
> +
> +static void send_stop_cmd(struct dw_mci *host, struct mmc_data *data)
> +{
> +	dw_mci_start_command(host, data->stop, host->stop_cmdr);
> +}

Explicit 'inline'?

> +
> +/* DMA interface functions */
> +static void dw_mci_stop_dma(struct dw_mci *host)
> +{
> +	if (host->use_dma) {
> +		host->dma_ops->stop(host);
> +		host->dma_ops->cleanup(host);
> +
> +	} else {
> +		/* Data transfer was stopped by the interrupt handler */
> +		set_bit(EVENT_XFER_COMPLETE, &host->pending_events);
> +	}
> +}
> +
> +#ifdef CONFIG_MMC_DW_IDMAC
> +static void dw_mci_dma_cleanup(struct dw_mci *host)
> +{
> +	struct mmc_data *data = host->data;
> +
> +	if (data)
> +		dma_unmap_sg(&host->pdev->dev, data->sg, data->sg_len,
> +		     ((data->flags & MMC_DATA_WRITE)
> +		      ? DMA_TO_DEVICE : DMA_FROM_DEVICE));
> +}
> +
> +static void dw_mci_idmac_stop_dma(struct dw_mci *host)
> +{
> +	u32 temp;
> +
> +	/* Disable and reset the IDMAC interface */
> +	temp = mci_readl(host, CTRL);
> +	temp &= ~SDMMC_CTRL_USE_IDMAC;
> +	temp |= SDMMC_CTRL_DMA_RESET;
> +	mci_writel(host, CTRL, temp);
> +
> +	/* Stop the IDMAC running */
> +	temp = mci_readl(host, BMOD);
> +	temp &= ~SDMMC_IDMAC_ENABLE;
> +	mci_writel(host, BMOD, temp);
> +}
> +
> +static void dw_mci_idmac_complete_dma(struct dw_mci *host)
> +{
> +	struct mmc_data *data = host->data;
> +
> +	dev_vdbg(&host->pdev->dev, "DMA complete\n");
> +
> +	host->dma_ops->cleanup(host);
> +
> +	/*
> +	 * If the card was removed, data will be NULL. No point in trying to
> +	 * send the stop command or waiting for NBUSY in this case.
> +	 */
> +	if (data) {
> +		set_bit(EVENT_XFER_COMPLETE, &host->pending_events);
> +		tasklet_schedule(&host->tasklet);
> +	}
> +}
> +
> +static void dw_mci_translate_sglist(struct dw_mci *host,
> +				    struct mmc_data *data, unsigned int sg_len)
> +{
> +	int i;
> +	struct idmac_desc *desc = host->sg_cpu;
> +
> +	for (i = 0; i < sg_len; i++, desc++) {
> +		unsigned int length = sg_dma_len(&data->sg[i]);
> +		u32 mem_addr = sg_dma_address(&data->sg[i]);
> +
> +		/* Set the OWN bit and disable interrupts for this descriptor */
> +		desc->des0 = IDMAC_DES0_OWN | IDMAC_DES0_DIC | IDMAC_DES0_CH;
> +
> +		/* Buffer length */
> +		IDMAC_SET_BUFFER1_SIZE(desc, length);
> +
> +		/* Physical address to DMA to/from */
> +		desc->des2 = mem_addr;
> +	}
> +
> +	/* Set first descriptor */
> +	desc = host->sg_cpu;
> +	desc->des0 |= IDMAC_DES0_FD;
> +
> +	/* Set last descriptor */
> +	desc = host->sg_cpu + (i - 1) * sizeof(struct idmac_desc);
> +	desc->des0 &= ~(IDMAC_DES0_CH | IDMAC_DES0_DIC);
> +	desc->des0 |= IDMAC_DES0_LD;
> +
> +	wmb();
> +}
> +
> +static void dw_mci_idmac_start_dma(struct dw_mci *host, unsigned int sg_len)
> +{
> +	u32 temp;
> +
> +	dw_mci_translate_sglist(host, host->data, sg_len);
> +
> +	/* Select IDMAC interface */
> +	temp = mci_readl(host, CTRL);
> +	temp |= SDMMC_CTRL_USE_IDMAC;
> +	mci_writel(host, CTRL, temp);
> +
> +	wmb();
> +
> +	/* Enable the IDMAC */
> +	temp = mci_readl(host, BMOD);
> +	temp |= SDMMC_IDMAC_ENABLE;
> +	mci_writel(host, BMOD, temp);
> +
> +	/* Start it running */
> +	mci_writel(host, PLDMND, 1);
> +}
> +
> +static int dw_mci_idmac_init(struct dw_mci *host)
> +{
> +	struct idmac_desc *p;
> +	int i;
> +
> +	/* Number of descriptors in the ring buffer */
> +	host->ring_size = PAGE_SIZE / sizeof(struct idmac_desc);
> +
> +	/* Forward link the descriptor list */
> +	for (i = 0, p = host->sg_cpu; i < host->ring_size - 1; i++, p++)
> +		p->des3 = host->sg_dma + (sizeof(struct idmac_desc) * (i + 1));
> +
> +	/* Set the last descriptor as the end-of-ring descriptor */
> +	p->des3 = host->sg_dma;
> +	p->des0 = IDMAC_DES0_ER;
> +
> +	/* Mask out interrupts - get Tx & Rx complete only */
> +	mci_writel(host, IDINTEN, SDMMC_IDMAC_INT_NI | SDMMC_IDMAC_INT_RI |
> +			SDMMC_IDMAC_INT_TI);
> +
> +	/* Set the descriptor base address */
> +	mci_writel(host, DBADDR, host->sg_dma);
> +	return 0;
> +}
> +
> +static struct dw_mci_dma_ops dw_mci_idmac_ops = {
> +	.init = dw_mci_idmac_init,
> +	.start = dw_mci_idmac_start_dma,
> +	.stop = dw_mci_idmac_stop_dma,
> +	.complete = dw_mci_idmac_complete_dma,
> +	.cleanup = dw_mci_dma_cleanup,
> +};
> +#endif /* CONFIG_MMC_DW_IDMAC */
> +
> +static int dw_mci_submit_data_dma(struct dw_mci *host, struct mmc_data *data)
> +{
> +	struct scatterlist *sg;
> +	unsigned int i, direction, sg_len;
> +	u32 temp;
> +
> +	/* If we don't have a channel, we can't do DMA */
> +	if (!host->use_dma)
> +		return -ENODEV;
> +
> +	/*
> +	 * We don't do DMA on "complex" transfers, i.e. with
> +	 * non-word-aligned buffers or lengths. Also, we don't bother
> +	 * with all the DMA setup overhead for short transfers.
> +	 */
> +	if (data->blocks * data->blksz < DW_MCI_DMA_THRESHOLD)
> +		return -EINVAL;
> +	if (data->blksz & 3)
> +		return -EINVAL;
> +
> +	for_each_sg(data->sg, sg, data->sg_len, i) {
> +		if (sg->offset & 3 || sg->length & 3)
> +			return -EINVAL;
> +	}
> +
> +	if (data->flags & MMC_DATA_READ)
> +		direction = DMA_FROM_DEVICE;
> +	else
> +		direction = DMA_TO_DEVICE;
> +
> +	sg_len = dma_map_sg(&host->pdev->dev, data->sg, data->sg_len,
> +				   direction);
> +
> +	dev_vdbg(&host->pdev->dev,
> +		"sd sg_cpu: %#lx sg_dma: %#lx sg_len: %d\n",
> +		(unsigned long)host->sg_cpu, (unsigned long)host->sg_dma,
> +		 sg_len);
> +
> +	/* Enable the DMA interface */
> +	temp = mci_readl(host, CTRL);
> +	temp |= SDMMC_CTRL_DMA_ENABLE;
> +	mci_writel(host, CTRL, temp);
> +
> +	/* disable irq of RX & TX, let DMA handle it */
> +	temp = mci_readl(host, INTMASK);
> +	temp  &= ~(SDMMC_INT_RXDR | SDMMC_INT_TXDR);
> +	mci_writel(host, INTMASK, temp);
> +
> +	host->dma_ops->start(host, sg_len);
> +
> +	return 0;
> +}
> +
> +static void dw_mci_submit_data(struct dw_mci *host, struct mmc_data *data)
> +{
> +	u32 temp;
> +
> +	data->error = -EINPROGRESS;
> +
> +	WARN_ON(host->data);
> +	host->sg = NULL;
> +	host->data = data;
> +
> +	if (dw_mci_submit_data_dma(host, data)) {
> +		host->sg = data->sg;
> +		host->pio_offset = 0;
> +		if (data->flags & MMC_DATA_READ)
> +			host->dir_status = DW_MCI_RECV_STATUS;
> +		else
> +			host->dir_status = DW_MCI_SEND_STATUS;
> +
> +		temp = mci_readl(host, INTMASK);
> +		temp |= SDMMC_INT_TXDR | SDMMC_INT_RXDR;
> +		mci_writel(host, INTMASK, temp);
> +
> +		temp = mci_readl(host, CTRL);
> +		temp &= ~SDMMC_CTRL_DMA_ENABLE;
> +		mci_writel(host, CTRL, temp);
> +	}
> +}
> +
> +static void mci_send_cmd(struct dw_mci_slot *slot, u32 cmd, u32 arg)
> +{
> +	struct dw_mci *host = slot->host;
> +	unsigned long timeout = jiffies + msecs_to_jiffies(500);
> +	unsigned int cmd_status = 0;
> +
> +	mci_writel(host, CMDARG, arg);
> +	wmb();
> +	mci_writel(host, CMD, SDMMC_CMD_START | cmd);
> +
> +	while (time_before(jiffies, timeout)) {
> +		cmd_status = mci_readl(host, CMD);
> +		if (!(cmd_status & SDMMC_CMD_START))
> +			return;
> +	}
> +	dev_err(&slot->mmc->class_dev,
> +		"Timeout sending command (cmd %#x arg %#x status %#x)\n",
> +		cmd, arg, cmd_status);
> +}
> +
> +static void dw_mci_setup_bus(struct dw_mci_slot *slot)
> +{
> +	struct dw_mci *host = slot->host;
> +	u32 div;
> +
> +	if (slot->clock != host->current_speed) {
> +		if (host->bus_hz % slot->clock)
> +			/*
> +			 * move the + 1 after the dvide
> +			 * to prevent over-clocking the card.
> +			 */
> +			div = ((host->bus_hz / slot->clock) >> 1) + 1;
> +		else
> +			div = (host->bus_hz  / slot->clock) >> 1;
> +
> +		dev_info(&slot->mmc->class_dev,
> +			"Bus speed (slot %d) = %dHz (slot req %dHz, actual %dHZ"
> +			" div = %d)\n",
> +			slot->id, host->bus_hz, slot->clock,
> +			div ? ((host->bus_hz / div) >> 1) : host->bus_hz, div);
> +
> +		/* disable clock */
> +		mci_writel(host, CLKENA, 0);
> +		mci_writel(host, CLKSRC, 0);
> +
> +		/* inform CIU */
> +		mci_send_cmd(slot,
> +			SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
> +
> +		/* set clock to desired speed */
> +		mci_writel(host, CLKDIV, div);
> +
> +		/* inform CIU */
> +		mci_send_cmd(slot,
> +			SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
> +
> +		/* enable clock */
> +		mci_writel(host, CLKENA, SDMMC_CLKEN_ENABLE);
> +
> +		/* inform CIU */
> +		mci_send_cmd(slot,
> +			SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
> +
> +		host->current_speed = slot->clock;
> +	}
> +
> +	/* Set the current slot bus width */
> +	mci_writel(host, CTYPE, slot->ctype);
> +}
> +
> +static void dw_mci_start_request(struct dw_mci *host,
> +				 struct dw_mci_slot *slot)
> +{
> +	struct mmc_request *mrq;
> +	struct mmc_command *cmd;
> +	struct mmc_data	*data;
> +	u32 cmdflags;
> +
> +	mrq = slot->mrq;
> +	/* no select the proper slot */
> +	if (host->pdata->select_slot)
> +		host->pdata->select_slot(slot->id);
> +
> +	/* Slot specific timing and width adjustment */
> +	dw_mci_setup_bus(slot);
> +
> +	host->cur_slot = slot;
> +	host->mrq = mrq;
> +
> +	host->pending_events = 0;
> +	host->completed_events = 0;
> +	host->data_status = 0;
> +
> +	data = mrq->data;
> +	if (data) {
> +		dw_mci_set_timeout(host);
> +		mci_writel(host, BYTCNT, data->blksz*data->blocks);
> +		mci_writel(host, BLKSIZ, data->blksz);
> +	}
> +
> +	cmd = mrq->cmd;
> +	cmdflags = dw_mci_prepare_command(slot->mmc, cmd);
> +
> +	/* this is the first command, lets send the initialization clock */
> +	if (unlikely(
> +		test_and_clear_bit(DW_MMC_CARD_NEED_INIT, &slot->flags))) {
> +		cmdflags |= SDMMC_CMD_INIT;
> +	}

This unlikely seems a bit over the top and forces an unfortunate break
in the line to keep within 80 cols. Maybe delete it?

> +
> +	/* we may need to move this code to mci_start_command */
> +	if (data) {
> +		dw_mci_submit_data(host, data);
> +		wmb();
> +	}
> +
> +	dw_mci_start_command(host, cmd, cmdflags);
> +
> +	if (mrq->stop)
> +		host->stop_cmdr = dw_mci_prepare_command(slot->mmc, mrq->stop);
> +}
> +
> +static void dw_mci_queue_request(struct dw_mci *host, struct dw_mci_slot *slot,
> +				 struct mmc_request *mrq)
> +{
> +	dev_vdbg(&slot->mmc->class_dev, "queue request: state=%d\n",
> +			host->state);
> +
> +	spin_lock_bh(&host->lock);
> +	slot->mrq = mrq;
> +
> +	if (host->state == STATE_IDLE) {
> +		host->state = STATE_SENDING_CMD;
> +		dw_mci_start_request(host, slot);
> +	} else {
> +		list_add_tail(&slot->queue_node, &host->queue);
> +	}
> +
> +	spin_unlock_bh(&host->lock);
> +}
> +
> +static void dw_mci_request(struct mmc_host *mmc, struct mmc_request *mrq)
> +{
> +	struct dw_mci_slot *slot = mmc_priv(mmc);
> +	struct dw_mci *host = slot->host;
> +
> +	WARN_ON(slot->mrq);
> +
> +	if (!test_bit(DW_MMC_CARD_PRESENT, &slot->flags)) {
> +		mrq->cmd->error = -ENOMEDIUM;
> +		mmc_request_done(mmc, mrq);
> +		return;
> +	}
> +
> +	/* We don't support multiple blocks of weird lengths. */
> +	dw_mci_queue_request(host, slot, mrq);
> +}
> +
> +static void dw_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> +{
> +	struct dw_mci_slot *slot = mmc_priv(mmc);
> +
> +	/* set default 1 bit mode */
> +	slot->ctype = SDMMC_CTYPE_1BIT;
> +
> +	switch (ios->bus_width) {
> +	case MMC_BUS_WIDTH_1:
> +		slot->ctype = SDMMC_CTYPE_1BIT;
> +		break;
> +	case MMC_BUS_WIDTH_4:
> +		slot->ctype = SDMMC_CTYPE_4BIT;
> +		break;
> +	}
> +
> +	if (ios->clock) {
> +		/*
> +		 * Use mirror of ios->clock to prevent race with mmc
> +		 * core ios update when finding the minimum.
> +		 */
> +		slot->clock = ios->clock;
> +	}
> +
> +	switch (ios->power_mode) {
> +	case MMC_POWER_UP:
> +		set_bit(DW_MMC_CARD_NEED_INIT, &slot->flags);
> +		break;
> +	default:
> +		break;
> +	}
> +}
> +
> +static int dw_mci_get_ro(struct mmc_host *mmc)
> +{
> +	int read_only;
> +	struct dw_mci_slot *slot = mmc_priv(mmc);
> +	struct dw_mci_board *brd = slot->host->pdata;
> +
> +	if (brd->get_ro != NULL) {
> +		read_only = brd->get_ro(slot->id);
> +	} else {
> +		/* Try on board write protect */
> +		read_only =
> +			mci_readl(slot->host, WRTPRT) & (1 << slot->id) ? 1 : 0;
> +	}
> +
> +	dev_dbg(&mmc->class_dev, "card is %s\n",
> +				read_only ? "read-only" : "read-write");
> +
> +	return read_only;
> +}
> +
> +static int dw_mci_get_cd(struct mmc_host *mmc)
> +{
> +	int present;
> +	struct dw_mci_slot *slot = mmc_priv(mmc);
> +	struct dw_mci_board *brd = slot->host->pdata;
> +
> +	if (brd->get_cd != NULL)
> +		present = !brd->get_cd(slot->id);
> +	else	/* try onboard card detect */
> +		present = (mci_readl(slot->host, CDETECT) & (1 << slot->id))
> +				== 0 ? 1 : 0;
> +
> +	dev_dbg(&mmc->class_dev, "card is %spresent\n", present ? "" : "not ");
> +
> +	return present;
> +}
> +
> +static const struct mmc_host_ops dw_mci_ops = {
> +	.request	= dw_mci_request,
> +	.set_ios	= dw_mci_set_ios,
> +	.get_ro		= dw_mci_get_ro,
> +	.get_cd		= dw_mci_get_cd,
> +};
> +
> +static void dw_mci_request_end(struct dw_mci *host, struct mmc_request *mrq)
> +	__releases(&host->lock)
> +	__acquires(&host->lock)
> +{
> +	struct dw_mci_slot *slot;
> +	struct mmc_host	*prev_mmc = host->cur_slot->mmc;
> +
> +	WARN_ON(host->cmd || host->data);
> +
> +	host->cur_slot->mrq = NULL;
> +	host->mrq = NULL;
> +	if (!list_empty(&host->queue)) {
> +		slot = list_entry(host->queue.next,
> +				struct dw_mci_slot, queue_node);
> +		list_del(&slot->queue_node);
> +		dev_vdbg(&host->pdev->dev, "list not empty: %s is next\n",
> +				mmc_hostname(slot->mmc));
> +		host->state = STATE_SENDING_CMD;
> +		dw_mci_start_request(host, slot);
> +	} else {
> +		dev_vdbg(&host->pdev->dev, "list empty\n");
> +		host->state = STATE_IDLE;
> +	}
> +
> +	spin_unlock(&host->lock);
> +	mmc_request_done(prev_mmc, mrq);
> +
> +	spin_lock(&host->lock);
> +}
> +
> +static void dw_mci_command_complete(struct dw_mci *host,
> +				    struct mmc_command *cmd)
> +{
> +	u32 status = host->cmd_status;
> +
> +	host->cmd_status = 0;
> +
> +	/* Read the response from the card (up to 16 bytes) */
> +	if (cmd->flags & MMC_RSP_PRESENT) {
> +		if (cmd->flags & MMC_RSP_136) {
> +			cmd->resp[3] = mci_readl(host, RESP0);
> +			cmd->resp[2] = mci_readl(host, RESP1);
> +			cmd->resp[1] = mci_readl(host, RESP2);
> +			cmd->resp[0] = mci_readl(host, RESP3);
> +		} else {
> +			cmd->resp[0] = mci_readl(host, RESP0);
> +			cmd->resp[1] = 0;
> +			cmd->resp[2] = 0;
> +			cmd->resp[3] = 0;
> +		}
> +	}
> +
> +	if (status & SDMMC_INT_RTO)
> +		cmd->error = -ETIMEDOUT;
> +	else if ((cmd->flags & MMC_RSP_CRC) && (status & SDMMC_INT_RCRC))
> +		cmd->error = -EILSEQ;
> +	else if (status & SDMMC_INT_RESP_ERR)
> +		cmd->error = -EIO;
> +	else
> +		cmd->error = 0;
> +
> +	if (cmd->error) {
> +		/* newer ip versions need a delay between retries */
> +		if (host->quirks & DW_MCI_QUIRK_RETRY_DELAY)
> +			mdelay(20);
> +
> +		if (cmd->data) {
> +			host->data = NULL;
> +			dw_mci_stop_dma(host);
> +		}
> +	}
> +}
> +
> +static void dw_mci_tasklet_func(unsigned long priv)
> +{
> +	struct dw_mci *host = (struct dw_mci *)priv;
> +	struct mmc_data	*data;
> +	struct mmc_command *cmd;
> +	enum dw_mci_state state;
> +	enum dw_mci_state prev_state;
> +	u32 status;
> +
> +	spin_lock(&host->lock);
> +
> +	state = host->state;
> +	data = host->data;
> +
> +	do {
> +		prev_state = state;
> +
> +		switch (state) {
> +		case STATE_IDLE:
> +			break;
> +
> +		case STATE_SENDING_CMD:
> +			if (!test_and_clear_bit(EVENT_CMD_COMPLETE,
> +						&host->pending_events))
> +				break;
> +
> +			cmd = host->cmd;
> +			host->cmd = NULL;
> +			set_bit(EVENT_CMD_COMPLETE, &host->completed_events);
> +			dw_mci_command_complete(host, host->mrq->cmd);
> +			if (!host->mrq->data || cmd->error) {
> +				dw_mci_request_end(host, host->mrq);
> +				goto unlock;
> +			}
> +
> +			prev_state = state = STATE_SENDING_DATA;
> +			/* fall through */
> +
> +		case STATE_SENDING_DATA:
> +			if (test_and_clear_bit(EVENT_DATA_ERROR,
> +					       &host->pending_events)) {
> +				dw_mci_stop_dma(host);
> +				if (data->stop)
> +					send_stop_cmd(host, data);
> +				state = STATE_DATA_ERROR;
> +				break;
> +			}
> +
> +			if (!test_and_clear_bit(EVENT_XFER_COMPLETE,
> +						&host->pending_events))
> +				break;
> +
> +			set_bit(EVENT_XFER_COMPLETE, &host->completed_events);
> +			prev_state = state = STATE_DATA_BUSY;
> +			/* fall through */
> +
> +		case STATE_DATA_BUSY:
> +			if (!test_and_clear_bit(EVENT_DATA_COMPLETE,
> +						&host->pending_events))
> +				break;
> +
> +			host->data = NULL;
> +			set_bit(EVENT_DATA_COMPLETE, &host->completed_events);
> +			status = host->data_status;
> +
> +			if (unlikely(status & DW_MCI_DATA_ERROR_FLAGS)) {
> +				if (status & SDMMC_INT_DTO) {
> +					dev_err(&host->pdev->dev,
> +							"data timeout error\n");
> +					data->error = -ETIMEDOUT;
> +				} else if (status & SDMMC_INT_DCRC) {
> +					dev_err(&host->pdev->dev,
> +							"data CRC error\n");
> +					data->error = -EILSEQ;
> +				} else {
> +					dev_err(&host->pdev->dev,
> +						"data FIFO error "
> +						"(status=%08x)\n",
> +						status);
> +					data->error = -EIO;
> +				}
> +			} else {
> +				data->bytes_xfered = data->blocks * data->blksz;
> +				data->error = 0;
> +			}
> +
> +			if (!data->stop) {
> +				dw_mci_request_end(host, host->mrq);
> +				goto unlock;
> +			}
> +
> +			prev_state = state = STATE_SENDING_STOP;
> +			if (!data->error)
> +				send_stop_cmd(host, data);
> +			/* fall through */
> +
> +		case STATE_SENDING_STOP:
> +			if (!test_and_clear_bit(EVENT_CMD_COMPLETE,
> +						&host->pending_events))
> +				break;
> +
> +			host->cmd = NULL;
> +			dw_mci_command_complete(host, host->mrq->stop);
> +			dw_mci_request_end(host, host->mrq);
> +			goto unlock;
> +
> +		case STATE_DATA_ERROR:
> +			if (!test_and_clear_bit(EVENT_XFER_COMPLETE,
> +						&host->pending_events))
> +				break;
> +
> +			state = STATE_DATA_BUSY;
> +			break;
> +		}
> +	} while (state != prev_state);
> +
> +	host->state = state;
> +unlock:
> +	spin_unlock(&host->lock);
> +
> +}
> +
> +static void dw_mci_push_data16(struct dw_mci *host, void *buf, int cnt)
> +{
> +	u16 *pData = (u16 *)buf;
> +
> +	WARN_ON(cnt % 2 != 0);
> +
> +	cnt = cnt >> 1;
> +	while (cnt > 0) {
> +		mci_writew(host, DATA, *pData++);
> +		cnt--;
> +	}
> +}
> +
> +static void dw_mci_pull_data16(struct dw_mci *host, void *buf, int cnt)
> +{
> +	u16 *pData = (u16 *)buf;
> +
> +	WARN_ON(cnt % 2 != 0);
> +
> +	cnt = cnt >> 1;
> +	while (cnt > 0) {
> +		*pData++ = mci_readw(host, DATA);
> +		cnt--;
> +	}
> +}
> +
> +static void dw_mci_push_data32(struct dw_mci *host, void *buf, int cnt)
> +{
> +	u32 *pData = (u32 *)buf;
> +
> +	WARN_ON(cnt % 4 != 0);
> +	WARN_ON((unsigned long)pData & 0x3);
> +
> +	cnt = cnt >> 2;
> +	while (cnt > 0) {
> +		mci_writel(host, DATA, *pData++);
> +		cnt--;
> +	}
> +}
> +
> +static void dw_mci_pull_data32(struct dw_mci *host, void *buf, int cnt)
> +{
> +	u32 *pData = (u32 *)buf;
> +
> +	WARN_ON(cnt % 4 != 0);
> +	WARN_ON((unsigned long)pData & 0x3);
> +
> +	cnt = cnt >> 2;
> +	while (cnt > 0) {
> +		*pData++ = mci_readl(host, DATA);
> +		cnt--;
> +	}
> +}
> +
> +static void dw_mci_push_data64(struct dw_mci *host, void *buf, int cnt)
> +{
> +	u64 *pData = (u64 *)buf;
> +
> +	WARN_ON(cnt % 8 != 0);
> +
> +	cnt = cnt >> 3;
> +	while (cnt > 0) {
> +		mci_writeq(host, DATA, *pData++);
> +		cnt--;
> +	}
> +}
> +
> +static void dw_mci_pull_data64(struct dw_mci *host, void *buf, int cnt)
> +{
> +	u64 *pData = (u64 *)buf;
> +
> +	WARN_ON(cnt % 8 != 0);
> +
> +	cnt = cnt >> 3;
> +	while (cnt > 0) {
> +		*pData++ = mci_readq(host, DATA);
> +		cnt--;
> +	}
> +}
> +
> +static void dw_mci_read_data_pio(struct dw_mci *host)
> +{
> +	struct scatterlist *sg = host->sg;
> +	void *buf = sg_virt(sg);
> +	unsigned int offset = host->pio_offset;
> +	struct mmc_data	*data = host->data;
> +	int shift = host->data_shift;
> +	u32 status;
> +	unsigned int nbytes = 0, len, old_len, count = 0;
> +
> +	do {
> +		len = SDMMC_GET_FCNT(mci_readl(host, STATUS)) << shift;
> +		if (count == 0)
> +			old_len = len;
> +
> +		if (likely(offset + len <= sg->length)) {
> +			host->pull_data(host, (void *)(buf + offset), len);
> +
> +			offset += len;
> +			nbytes += len;
> +
> +			if (offset == sg->length) {
> +				flush_dcache_page(sg_page(sg));
> +				host->sg = sg = sg_next(sg);
> +				if (!sg)
> +					goto done;
> +
> +				offset = 0;
> +				buf = sg_virt(sg);
> +			}
> +		} else {
> +			unsigned int remaining = sg->length - offset;
> +			host->pull_data(host,
> +				(void *)(buf + offset), remaining);
> +			nbytes += remaining;
> +
> +			flush_dcache_page(sg_page(sg));
> +			host->sg = sg = sg_next(sg);
> +			if (!sg)
> +				goto done;
> +
> +			offset = len - remaining;
> +			buf = sg_virt(sg);
> +			host->pull_data(host, buf, offset);
> +			nbytes += offset;
> +		}
> +
> +		status = mci_readl(host, MINTSTS);
> +		mci_writel(host, RINTSTS, SDMMC_INT_RXDR);
> +		if (status & DW_MCI_DATA_ERROR_FLAGS) {
> +			host->data_status = status;
> +			data->bytes_xfered += nbytes;
> +			smp_wmb();
> +
> +			set_bit(EVENT_DATA_ERROR, &host->pending_events);
> +
> +			tasklet_schedule(&host->tasklet);
> +			return;
> +		}
> +		count++;
> +	} while (status & SDMMC_INT_RXDR); /*if the RXDR is ready
> +						lets read again*/
> +	len = SDMMC_GET_FCNT(mci_readl(host, STATUS));
> +	host->pio_offset = offset;
> +	data->bytes_xfered += nbytes;
> +	return;
> +
> +done:
> +	data->bytes_xfered += nbytes;
> +	smp_wmb();
> +	set_bit(EVENT_XFER_COMPLETE, &host->pending_events);
> +}
> +
> +static void dw_mci_write_data_pio(struct dw_mci *host)
> +{
> +	struct scatterlist *sg = host->sg;
> +	void *buf = sg_virt(sg);
> +	unsigned int offset = host->pio_offset;
> +	struct mmc_data	*data = host->data;
> +	int shift = host->data_shift;
> +	u32 status;
> +	unsigned int nbytes = 0, len;
> +
> +	do {
> +		len = SDMMC_FIFO_SZ -
> +			(SDMMC_GET_FCNT(mci_readl(host, STATUS)) << shift);
> +		if (likely(offset + len <= sg->length)) {
> +			host->push_data(host, (void *)(buf + offset), len);
> +
> +			offset += len;
> +			nbytes += len;
> +			if (offset == sg->length) {
> +				host->sg = sg = sg_next(sg);
> +				if (!sg)
> +					goto done;
> +
> +				offset = 0;
> +				buf = sg_virt(sg);
> +			}
> +		} else {
> +			unsigned int remaining = sg->length - offset;
> +
> +			host->push_data(host,
> +				(void *)(buf + offset), remaining);
> +			nbytes += remaining;
> +
> +			host->sg = sg = sg_next(sg);
> +			if (!sg)
> +				goto done;
> +
> +			offset = len - remaining;
> +			buf = sg_virt(sg);
> +			host->push_data(host, (void *)buf, offset);
> +			nbytes += offset;
> +		}
> +
> +		status = mci_readl(host, MINTSTS);
> +		mci_writel(host, RINTSTS, SDMMC_INT_TXDR);
> +		if (status & DW_MCI_DATA_ERROR_FLAGS) {
> +			host->data_status = status;
> +			data->bytes_xfered += nbytes;
> +
> +			smp_wmb();
> +
> +			set_bit(EVENT_DATA_ERROR, &host->pending_events);
> +
> +			tasklet_schedule(&host->tasklet);
> +			return;
> +		}
> +	} while (status & SDMMC_INT_TXDR); /* if TXDR, lets write again */
> +
> +	host->pio_offset = offset;
> +	data->bytes_xfered += nbytes;
> +
> +	return;
> +
> +done:
> +	data->bytes_xfered += nbytes;
> +	smp_wmb();
> +	set_bit(EVENT_XFER_COMPLETE, &host->pending_events);
> +}
> +
> +static void dw_mci_cmd_interrupt(struct dw_mci *host, u32 status)
> +{
> +	if (!host->cmd_status)
> +		host->cmd_status = status;
> +
> +	smp_wmb();
> +
> +	set_bit(EVENT_CMD_COMPLETE, &host->pending_events);
> +	tasklet_schedule(&host->tasklet);
> +}
> +
> +static irqreturn_t dw_mci_interrupt(int irq, void *dev_id)
> +{
> +	struct dw_mci *host = dev_id;
> +	u32 status,  pending;
> +	unsigned int pass_count = 0;
> +
> +	do {
> +		status = mci_readl(host, RINTSTS);
> +		pending = mci_readl(host, MINTSTS);/* read only mask reg */
> +
> +		/*
> +		 * DTO fix - version 2.10a and below, and only if internal DMA
> +		 * is configured.
> +		 */
> +		if (host->quirks & DW_MCI_QUIRK_IDMAC_DTO) {
> +			if (!pending &&
> +			    ((mci_readl(host, STATUS) >> 17) & 0x1fff))
> +				pending |= SDMMC_INT_DATA_OVER;
> +		}
> +
> +		if (!pending)
> +			break;
> +
> +		if (pending & DW_MCI_CMD_ERROR_FLAGS) {
> +			mci_writel(host, RINTSTS, DW_MCI_CMD_ERROR_FLAGS);
> +			host->cmd_status = status;
> +			smp_wmb();
> +			set_bit(EVENT_CMD_COMPLETE, &host->pending_events);
> +			tasklet_schedule(&host->tasklet);
> +		}
> +
> +		if (pending & DW_MCI_DATA_ERROR_FLAGS) {
> +			/* if there is an error, lets report DATA_ERROR */
> +			mci_writel(host, RINTSTS, DW_MCI_DATA_ERROR_FLAGS);
> +			host->data_status = status;
> +			smp_wmb();
> +			set_bit(EVENT_DATA_ERROR, &host->pending_events);
> +			tasklet_schedule(&host->tasklet);
> +		}
> +
> +
> +		if (pending & SDMMC_INT_DATA_OVER) {
> +			mci_writel(host, RINTSTS, SDMMC_INT_DATA_OVER);
> +			if (!host->data_status)
> +				host->data_status = status;
> +			smp_wmb();
> +			if (host->dir_status == DW_MCI_RECV_STATUS) {
> +				if (host->sg != NULL)
> +					dw_mci_read_data_pio(host);
> +			}
> +			set_bit(EVENT_DATA_COMPLETE, &host->pending_events);
> +			tasklet_schedule(&host->tasklet);
> +		}
> +
> +		if (pending & SDMMC_INT_RXDR) {
> +			mci_writel(host, RINTSTS, SDMMC_INT_RXDR);
> +			if (host->sg)
> +				dw_mci_read_data_pio(host);
> +		}
> +
> +		if (pending & SDMMC_INT_TXDR) {
> +			mci_writel(host, RINTSTS, SDMMC_INT_TXDR);
> +			if (host->sg)
> +				dw_mci_write_data_pio(host);
> +		}
> +
> +		if (pending & SDMMC_INT_CMD_DONE) {
> +			mci_writel(host, RINTSTS, SDMMC_INT_CMD_DONE);
> +			dw_mci_cmd_interrupt(host, status);
> +		}
> +
> +		if (pending & SDMMC_INT_CD) {
> +			mci_writel(host, RINTSTS, SDMMC_INT_CD);
> +			tasklet_schedule(&host->card_tasklet);
> +		}
> +
> +	} while (pass_count++ < 5);

This could do with a comment, explaining why it's necessary to loop 5
times.

> +
> +#ifdef CONFIG_MMC_DW_IDMAC
> +	/* Handle DMA interrupts */
> +	pending = mci_readl(host, IDSTS);
> +	if (pending & (SDMMC_IDMAC_INT_TI | SDMMC_IDMAC_INT_RI)) {
> +		mci_writel(host, IDSTS, SDMMC_IDMAC_INT_TI |
> +				SDMMC_IDMAC_INT_RI);
> +		mci_writel(host, IDSTS, SDMMC_IDMAC_INT_NI);
> +		set_bit(EVENT_DATA_COMPLETE, &host->pending_events);
> +		host->dma_ops->complete(host);
> +	}
> +#endif
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static void dw_mci_tasklet_card(unsigned long data)
> +{
> +	struct dw_mci *host = (struct dw_mci *)data;
> +	int i;
> +
> +	for (i = 0; i < host->num_slots; i++) {
> +		struct dw_mci_slot *slot = host->slot[i];
> +		struct mmc_host *mmc = slot->mmc;
> +		struct mmc_request *mrq;
> +		int present;
> +		u32 ctrl;
> +
> +		present = dw_mci_get_cd(mmc);
> +		while (present != slot->last_detect_state) {
> +			spin_lock(&host->lock);
> +
> +			dev_dbg(&slot->mmc->class_dev, "card %s\n",
> +					present ? "inserted" : "removed");
> +
> +			/* Card change detected */
> +			slot->last_detect_state = present;
> +
> +			/* Power up slot */
> +			if (present != 0) {
> +				if (host->pdata->setpower)
> +					host->pdata->setpower(slot->id,
> +						mmc->ocr_avail);
> +
> +				set_bit(DW_MMC_CARD_PRESENT, &slot->flags);
> +			}
> +
> +			/* Clean up queue if present */
> +			mrq = slot->mrq;
> +			if (mrq) {
> +				if (mrq == host->mrq) {
> +					host->data = NULL;
> +					host->cmd = NULL;
> +
> +					switch (host->state) {
> +					case STATE_IDLE:
> +						break;
> +					case STATE_SENDING_CMD:
> +						mrq->cmd->error = -ENOMEDIUM;
> +						if (!mrq->data)
> +							break;
> +						/* fall through */
> +					case STATE_SENDING_DATA:
> +						mrq->data->error = -ENOMEDIUM;
> +						dw_mci_stop_dma(host);
> +						break;
> +					case STATE_DATA_BUSY:
> +					case STATE_DATA_ERROR:
> +						if (mrq->data->error == -EINPROGRESS)
> +							mrq->data->error = -ENOMEDIUM;
> +						if (!mrq->stop)
> +							break;
> +						/* fall through */
> +					case STATE_SENDING_STOP:
> +						mrq->stop->error = -ENOMEDIUM;
> +						break;
> +					}
> +
> +					dw_mci_request_end(host, mrq);
> +				} else {
> +					list_del(&slot->queue_node);
> +					mrq->cmd->error = -ENOMEDIUM;
> +					if (mrq->data)
> +						mrq->data->error = -ENOMEDIUM;
> +					if (mrq->stop)
> +						mrq->stop->error = -ENOMEDIUM;
> +
> +					spin_unlock(&host->lock);
> +					mmc_request_done(slot->mmc, mrq);
> +					spin_lock(&host->lock);
> +				}
> +			}
> +
> +			/* Power down slot */
> +			if (present == 0) {
> +				if (host->pdata->setpower)
> +					host->pdata->setpower(slot->id, 0);
> +				clear_bit(DW_MMC_CARD_PRESENT, &slot->flags);
> +
> +				/*
> +				 * Clear down the FIFO - doing so generates a
> +				 * block interrupt, hence setting the
> +				 * scatter-gather pointer to NULL.
> +				 */
> +				host->sg = NULL;
> +
> +				ctrl = mci_readl(host, CTRL);
> +				ctrl |= SDMMC_CTRL_FIFO_RESET;
> +				mci_writel(host, CTRL, ctrl);
> +
> +#ifdef CONFIG_MMC_DW_IDMAC
> +				ctrl = mci_readl(host, BMOD);
> +				ctrl |= 0x01;	/* Software reset of DMA */
> +				mci_writel(host, BMOD, ctrl);
> +#endif
> +
> +			}
> +
> +			spin_unlock(&host->lock);
> +			present = dw_mci_get_cd(mmc);
> +		}
> +
> +		mmc_detect_change(slot->mmc,
> +			msecs_to_jiffies(host->pdata->detect_delay_ms));
> +	}
> +}
> +
> +static int __init dw_mci_init_slot(struct dw_mci *host, unsigned int id)
> +{
> +	struct mmc_host *mmc;
> +	struct dw_mci_slot *slot;
> +
> +	mmc = mmc_alloc_host(sizeof(struct dw_mci_slot), &host->pdev->dev);
> +	if (!mmc)
> +		return -ENOMEM;
> +
> +	slot = mmc_priv(mmc);
> +	slot->id = id;
> +	slot->mmc = mmc;
> +	slot->host = host;
> +
> +	mmc->ops = &dw_mci_ops;
> +	mmc->f_min = DIV_ROUND_UP(host->bus_hz, 510);

Is that really supposed to be 510, and not 512?

> +	mmc->f_max = host->bus_hz;
> +
> +	if (host->pdata->get_ocr)
> +		mmc->ocr_avail = host->pdata->get_ocr(id);
> +	else
> +		mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
> +
> +	/*
> +	 * Start with slot power disabled,
> +	 * will be enabled when card is detected
> +	 */
> +	if (host->pdata->setpower)
> +		host->pdata->setpower(id, 0);
> +
> +	mmc->caps = 0;
> +	if (host->pdata->get_bus_wd)
> +		if (host->pdata->get_bus_wd(slot->id) >= 4)
> +			mmc->caps |= MMC_CAP_4_BIT_DATA;
> +
> +	if (host->pdata->quirks & DW_MCI_QUIRK_HIGHSPEED)
> +		mmc->caps |= MMC_CAP_SD_HIGHSPEED;
> +
> +#ifdef CONFIG_MMC_DW_IDMAC
> +	mmc->max_segs = host->ring_size;
> +	mmc->max_blk_size = 65536;
> +	mmc->max_blk_count = host->ring_size;
> +	mmc->max_seg_size = 0x1000;
> +	mmc->max_req_size = mmc->max_seg_size * mmc->max_blk_count;
> +#else
> +	if (host->pdata->blk_settings) {
> +		mmc->max_segs = host->pdata->blk_settings->max_segs;
> +		mmc->max_blk_size = host->pdata->blk_settings->max_blk_size;
> +		mmc->max_blk_count = host->pdata->blk_settings->max_blk_count;
> +		mmc->max_req_size = host->pdata->blk_settings->max_req_size;
> +		mmc->max_seg_size = host->pdata->blk_settings->max_seg_size;
> +	} else {
> +		/*useful defaults*/
> +		mmc->max_segs = 64;
> +		mmc->max_blk_size = 65536; /* BLKSIZ is 16 bits */
> +		mmc->max_blk_count = 512;
> +		mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
> +		mmc->max_seg_size = mmc->max_req_size;
> +	}
> +#endif /* CONFIG_MMC_DW_IDMAC */
> +
> +	/* Assume card is present initially */
> +	if (dw_mci_get_cd(mmc))
> +		set_bit(DW_MMC_CARD_PRESENT, &slot->flags);
> +	else
> +		clear_bit(DW_MMC_CARD_PRESENT, &slot->flags);
> +
> +	host->slot[id] = slot;
> +	mmc_add_host(mmc);
> +
> +#if defined(CONFIG_DEBUG_FS)
> +	dw_mci_init_debugfs(slot);
> +#endif
> +
> +	/* Card initially undetected */
> +	slot->last_detect_state = 0;
> +
> +	return 0;
> +}
> +
> +static void dw_mci_cleanup_slot(struct dw_mci_slot *slot,
> +				unsigned int id)
> +{
> +	/* Shutdown detect IRQ */
> +	if (slot->host->pdata->exit)
> +		slot->host->pdata->exit(id);
> +
> +	/* Debugfs stuff is cleaned up by mmc core */
> +	mmc_remove_host(slot->mmc);
> +	slot->host->slot[id] = NULL;
> +	mmc_free_host(slot->mmc);
> +}
> +
> +static void dw_mci_init_dma(struct dw_mci *host)
> +{
> +	/* Alloc memory for sg translation */
> +	host->sg_cpu = dma_alloc_coherent(&host->pdev->dev, PAGE_SIZE,
> +			&host->sg_dma, GFP_KERNEL);
> +	if (!host->sg_cpu) {
> +		dev_err(&host->pdev->dev, "%s: could not alloc DMA memory\n",
> +				__func__);
> +		goto no_dma;
> +	}
> +
> +	/* Determine which DMA interface to use */
> +#ifdef CONFIG_MMC_DW_IDMAC
> +	host->dma_ops = &dw_mci_idmac_ops;
> +	dev_info(&host->pdev->dev, "Using internal DMA controller.\n");
> +#endif
> +
> +	if (!host->dma_ops)
> +		goto no_dma;
> +
> +	if (host->dma_ops->init) {
> +		if (host->dma_ops->init(host)) {
> +			dev_err(&host->pdev->dev, "%s: Unable to initialise "
> +					"DMA Controller.\n", __func__);
> +			goto no_dma;
> +		}
> +	} else {
> +		dev_err(&host->pdev->dev, "DMA initialisation not found.\n");
> +		goto no_dma;
> +	}
> +
> +	host->use_dma = 1;
> +	return;
> +
> +no_dma:
> +	dev_info(&host->pdev->dev, "Using PIO mode.\n");
> +	host->use_dma = 0;
> +	return;
> +}
> +
> +static bool mci_wait_reset(struct device *dev, struct dw_mci *host)
> +{
> +	unsigned long timeout = jiffies + msecs_to_jiffies(500);
> +	unsigned int ctrl;
> +
> +	mci_writel(host, CTRL, (SDMMC_CTRL_RESET |
> +			SDMMC_CTRL_FIFO_RESET | SDMMC_CTRL_DMA_RESET));
> +
> +	/* wait till resets clear */
> +	do {
> +		ctrl = mci_readl(host, CTRL);
> +		if (!(ctrl & (SDMMC_CTRL_RESET |
> +			      SDMMC_CTRL_FIFO_RESET | SDMMC_CTRL_DMA_RESET)))
> +			return true;
> +	} while (time_before(jiffies, timeout));
> +
> +	dev_err(dev, "Timeout resetting block (ctrl %#x)\n", ctrl);
> +
> +	return false;
> +}
> +
> +static int dw_mci_probe(struct platform_device *pdev)
> +{
> +	struct dw_mci *host;
> +	struct resource	*regs;
> +	struct dw_mci_board *pdata;
> +	int irq, ret, i, width;
> +	u32 fifo_size;
> +
> +	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!regs)
> +		return -ENXIO;
> +
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0)
> +		return irq;
> +
> +	host = kzalloc(sizeof(struct dw_mci), GFP_KERNEL);
> +	if (!host)
> +		return -ENOMEM;
> +
> +	host->pdev = pdev;
> +	host->pdata = pdata = pdev->dev.platform_data;
> +	if (!pdata) {
> +		dev_err(&pdev->dev, "Platform data missing\n");
> +		ret = -ENODEV;
> +		goto err_freehost;
> +	}
> +
> +	if (((pdata->num_slots > 1) && !(pdata->select_slot))
> +			|| !(pdata->init)) {
> +		dev_err(&pdev->dev, "Platform data wrong\n");
> +		ret = -ENODEV;
> +		goto err_freehost;
> +	}
> +
> +	if (!pdata->bus_hz) {
> +		dev_err(&pdev->dev,
> +			"Bus speed undefined in platform data!\n");
> +		ret = -ENODEV;
> +		goto err_freehost;
> +	}
> +
> +	host->bus_hz = pdata->bus_hz;
> +	host->quirks = pdata->quirks;
> +
> +	spin_lock_init(&host->lock);
> +	INIT_LIST_HEAD(&host->queue);
> +
> +	ret = -ENOMEM;
> +	host->regs = ioremap(regs->start, regs->end - regs->start + 1);
> +	if (!host->regs)
> +		goto err_freehost;
> +
> +	host->dma_ops = pdata->dma_ops;
> +	dw_mci_init_dma(host);
> +
> +	/*
> +	 * Get the host data width - this assumes that HCON has been set with
> +	 * the correct values.
> +	 */
> +	i = (mci_readl(host, HCON) >> 7) & 0x7;
> +	if (!i) {
> +		host->push_data = dw_mci_push_data16;
> +		host->pull_data = dw_mci_pull_data16;
> +		width = 16;
> +		host->data_shift = 1;
> +	} else if (i == 2) {
> +		host->push_data = dw_mci_push_data64;
> +		host->pull_data = dw_mci_pull_data64;
> +		width = 64;
> +		host->data_shift = 3;
> +	} else {
> +		/* Check for a reserved value, and warn if it is */
> +		WARN((i != 1),
> +			"HCON reports a reserved host data width!\n"
> +			"Defaulting to 32-bit access.\n");
> +		host->push_data = dw_mci_push_data32;
> +		host->pull_data = dw_mci_pull_data32;
> +		width = 32;
> +		host->data_shift = 2;
> +	}
> +
> +	/* reset all blocks */
> +	if (!mci_wait_reset(&pdev->dev, host)) {
> +		ret = -ENODEV;
> +		goto err_dmaunmap;
> +	}
> +
> +	 /* Clear the interrupts for the host controller */
> +	mci_writel(host, RINTSTS, 0xFFFFFFFF);
> +	mci_writel(host, INTMASK, 0); /* disable all mmc interrupt first */
> +
> +	/* Put in max timeout */
> +	mci_writel(host, TMOUT, 0xFFFFFFFF);
> +
> +	/*
> +	 * FIFO threshold settings  RxMark = fifo_size/2-1,
> +	 *                          Tx Mark =fifo_size/2 DMA Size = 8
> +	 */
> +	fifo_size = mci_readl(host, FIFOTH);
> +	fifo_size = (fifo_size >> 16) & 0x7ff;
> +	mci_writel(host, FIFOTH, ((0x2 << 28) | ((fifo_size/2 - 1) << 16) |
> +				((fifo_size/2) << 0)));
> +
> +	/* disable clock to CIU */
> +	mci_writel(host, CLKENA, 0);
> +	mci_writel(host, CLKSRC, 0);
> +
> +	tasklet_init(&host->tasklet, dw_mci_tasklet_func, (unsigned long)host);
> +	tasklet_init(&host->card_tasklet,
> +		dw_mci_tasklet_card, (unsigned long)host);
> +
> +	ret = request_irq(irq, dw_mci_interrupt, 0, "dw-mci", host);
> +	if (ret)
> +		goto err_dmaunmap;
> +
> +	platform_set_drvdata(pdev, host);
> +
> +	if (host->pdata->num_slots)
> +		host->num_slots = host->pdata->num_slots;
> +	else
> +		host->num_slots = ((mci_readl(host, HCON) >> 1) & 0x1F) + 1;
> +
> +	/* We need at least one slot to succeed ####pd####*/
> +	for (i = 0; i < host->num_slots; i++) {
> +		ret = dw_mci_init_slot(host, i);
> +		if (ret) {
> +			ret = -ENODEV;
> +			goto err_init_slot;
> +		}
> +	}
> +
> +	/*
> +	 * enable interrupt for command done, data over, data empty,
> +	 * receive ready and error such as transmit, receive timeout, crc error
> +	 */
> +	mci_writel(host, RINTSTS, 0xFFFFFFFF);
> +	mci_writel(host, INTMASK, SDMMC_INT_CMD_DONE | SDMMC_INT_DATA_OVER |
> +				SDMMC_INT_TXDR | SDMMC_INT_RXDR |
> +				DW_MCI_ERROR_FLAGS | SDMMC_INT_CD);
> +	mci_writel(host, CTRL, SDMMC_CTRL_INT_ENABLE); /*enable mci interrupt*/
> +
> +	dev_info(&pdev->dev, "DW MMC controller at irq %d, "
> +			"%d bit host data width\n",
> +			irq, width);
> +	if (host->quirks & DW_MCI_QUIRK_IDMAC_DTO)
> +		dev_info(&pdev->dev, "Internal DMAC interrupt fix enabled.\n");
> +
> +	return 0;
> +
> +err_init_slot:
> +	/* De-init any initialized slots */
> +	while (i > 0) {
> +		if (host->slot[i])
> +			dw_mci_cleanup_slot(host->slot[i], i);
> +		i--;
> +	}
> +	free_irq(irq, host);
> +
> +err_dmaunmap:
> +	if (host->use_dma && host->dma_ops->exit)
> +		host->dma_ops->exit(host);
> +	dma_free_coherent(&host->pdev->dev, PAGE_SIZE,
> +			host->sg_cpu, host->sg_dma);
> +	iounmap(host->regs);
> +
> +err_freehost:
> +	kfree(host);
> +	return ret;
> +}
> +
> +static int __exit dw_mci_remove(struct platform_device *pdev)
> +{
> +	struct dw_mci *host = platform_get_drvdata(pdev);
> +	int i;
> +
> +	mci_writel(host, RINTSTS, 0xFFFFFFFF);
> +	mci_writel(host, INTMASK, 0); /* disable all mmc interrupt first */
> +
> +	platform_set_drvdata(pdev, NULL);
> +
> +	for (i = 0; i < host->num_slots; i++) {
> +		dev_dbg(&pdev->dev, "remove slot %d\n", i);
> +		if (host->slot[i])
> +			dw_mci_cleanup_slot(host->slot[i], i);
> +	}
> +
> +	/* disable clock to CIU */
> +	mci_writel(host, CLKENA, 0);
> +	mci_writel(host, CLKSRC, 0);
> +
> +	free_irq(platform_get_irq(pdev, 0), host);
> +	dma_free_coherent(&pdev->dev, PAGE_SIZE, host->sg_cpu, host->sg_dma);
> +
> +	if (host->use_dma && host->dma_ops->exit)
> +		host->dma_ops->exit(host);
> +
> +	iounmap(host->regs);
> +
> +	kfree(host);
> +	return 0;
> +}
> +
> +#ifdef CONFIG_PM
> +/*
> + * TODO: we should probably disable the clock to the card in the suspend path.
> + */
> +static int dw_mci_suspend(struct platform_device *pdev, pm_message_t mesg)
> +{
> +	int i, ret;
> +	struct dw_mci *host = platform_get_drvdata(pdev);
> +
> +	for (i = 0; i < host->num_slots; i++) {
> +		struct dw_mci_slot *slot = host->slot[i];
> +		if (!slot)
> +			continue;
> +		ret = mmc_suspend_host(slot->mmc);
> +		if (ret < 0) {
> +			while (--i >= 0) {
> +				slot = host->slot[i];
> +				if (slot)
> +					mmc_resume_host(host->slot[i]->mmc);
> +			}
> +			return ret;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static int dw_mci_resume(struct platform_device *pdev)
> +{
> +	int i, ret;
> +	struct dw_mci *host = platform_get_drvdata(pdev);
> +
> +	for (i = 0; i < host->num_slots; i++) {
> +		struct dw_mci_slot *slot = host->slot[i];
> +		if (!slot)
> +			continue;
> +		ret = mmc_resume_host(host->slot[i]->mmc);
> +		if (ret < 0)
> +			return ret;
> +	}
> +
> +	return 0;
> +}
> +#else
> +#define dw_mci_suspend	NULL
> +#define dw_mci_resume	NULL
> +#endif /* CONFIG_PM */
> +
> +static struct platform_driver dw_mci_driver = {
> +	.remove		= __exit_p(dw_mci_remove),
> +	.suspend	= dw_mci_suspend,
> +	.resume		= dw_mci_resume,
> +	.driver		= {
> +		.name		= "dw_mmc",
> +	},
> +};
> +
> +static int __init dw_mci_init(void)
> +{
> +	return platform_driver_probe(&dw_mci_driver, dw_mci_probe);
> +}
> +
> +static void __exit dw_mci_exit(void)
> +{
> +	platform_driver_unregister(&dw_mci_driver);
> +}
> +
> +module_init(dw_mci_init);
> +module_exit(dw_mci_exit);
> +
> +MODULE_DESCRIPTION("DW Multimedia Card Interface driver");
> +MODULE_AUTHOR("NXP Semiconductor VietNam");
> +MODULE_AUTHOR("Imagination Technologies Ltd");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h
> new file mode 100644
> index 0000000..65bcff7
> --- /dev/null
> +++ b/drivers/mmc/host/dw_mmc.h
> @@ -0,0 +1,155 @@
> +/*
> + * Synopsys DesignWare Multimedia Card Interface driver
> + *  (Based on NXP driver for lpc 31xx)
> + *
> + * Copyright (C) 2009 NXP Semiconductors
> + * Copyright (C) 2009, 2010 Imagination Technologies Ltd.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + */
> +
> +#ifndef _DW_MMC_H_
> +#define _DW_MMC_H_
> +
> +#define MCI_SLOT		0

This appears to be unused.

> +
> +#define SDMMC_CTRL		0x000
> +#define SDMMC_PWREN		0x004
> +#define SDMMC_CLKDIV		0x008
> +#define SDMMC_CLKSRC		0x00c
> +#define SDMMC_CLKENA		0x010
> +#define SDMMC_TMOUT		0x014
> +#define SDMMC_CTYPE		0x018
> +#define SDMMC_BLKSIZ		0x01c
> +#define SDMMC_BYTCNT		0x020
> +#define SDMMC_INTMASK		0x024
> +#define SDMMC_CMDARG		0x028
> +#define SDMMC_CMD		0x02c
> +#define SDMMC_RESP0		0x030
> +#define SDMMC_RESP1		0x034
> +#define SDMMC_RESP2		0x038
> +#define SDMMC_RESP3		0x03c
> +#define SDMMC_MINTSTS		0x040
> +#define SDMMC_RINTSTS		0x044
> +#define SDMMC_STATUS		0x048
> +#define SDMMC_FIFOTH		0x04c
> +#define SDMMC_CDETECT		0x050
> +#define SDMMC_WRTPRT		0x054
> +#define SDMMC_GPIO		0x058
> +#define SDMMC_TCBCNT		0x05c
> +#define SDMMC_TBBCNT		0x060
> +#define SDMMC_DEBNCE		0x064
> +#define SDMMC_USRID		0x068
> +#define SDMMC_VERID		0x06c
> +#define SDMMC_HCON		0x070
> +#define SDMMC_BMOD		0x080
> +#define SDMMC_PLDMND		0x084
> +#define SDMMC_DBADDR		0x088
> +#define SDMMC_IDSTS		0x08c
> +#define SDMMC_IDINTEN		0x090
> +#define SDMMC_DSCADDR		0x094
> +#define SDMMC_BUFADDR		0x098
> +#define SDMMC_DATA		0x100
> +#define SDMMC_DATA_ADR		0x100
> +
> +/* shift bit field */
> +#define _SBF(f, v)		((v) << (f))
> +
> +/* Control register defines */
> +#define SDMMC_CTRL_USE_IDMAC		BIT(25)
> +#define SDMMC_CTRL_CEATA_INT_EN		BIT(11)
> +#define SDMMC_CTRL_SEND_AS_CCSD		BIT(10)
> +#define SDMMC_CTRL_SEND_CCSD		BIT(9)
> +#define SDMMC_CTRL_ABRT_READ_DATA	BIT(8)
> +#define SDMMC_CTRL_SEND_IRQ_RESP	BIT(7)
> +#define SDMMC_CTRL_READ_WAIT		BIT(6)
> +#define SDMMC_CTRL_DMA_ENABLE		BIT(5)
> +#define SDMMC_CTRL_INT_ENABLE		BIT(4)
> +#define SDMMC_CTRL_DMA_RESET		BIT(2)
> +#define SDMMC_CTRL_FIFO_RESET		BIT(1)
> +#define SDMMC_CTRL_RESET		BIT(0)
> +/* Clock Enable register defines */
> +#define SDMMC_CLKEN_LOW_PWR		BIT(16)
> +#define SDMMC_CLKEN_ENABLE		BIT(0)
> +/* time-out register defines */
> +#define SDMMC_TMOUT_DATA(n)		_SBF(8, (n))
> +#define SDMMC_TMOUT_DATA_MSK		0xFFFFFF00
> +#define SDMMC_TMOUT_RESP(n)		((n) & 0xFF)
> +#define SDMMC_TMOUT_RESP_MSK		0xFF
> +/* card-type register defines */
> +#define SDMMC_CTYPE_8BIT		BIT(16)
> +#define SDMMC_CTYPE_4BIT		BIT(0)
> +#define SDMMC_CTYPE_1BIT		0
> +/* Interrupt status & mask register defines */
> +#define SDMMC_INT_SDIO			BIT(16)
> +#define SDMMC_INT_EBE			BIT(15)
> +#define SDMMC_INT_ACD			BIT(14)
> +#define SDMMC_INT_SBE			BIT(13)
> +#define SDMMC_INT_HLE			BIT(12)
> +#define SDMMC_INT_FRUN			BIT(11)
> +#define SDMMC_INT_HTO			BIT(10)
> +#define SDMMC_INT_DTO			BIT(9)
> +#define SDMMC_INT_RTO			BIT(8)
> +#define SDMMC_INT_DCRC			BIT(7)
> +#define SDMMC_INT_RCRC			BIT(6)
> +#define SDMMC_INT_RXDR			BIT(5)
> +#define SDMMC_INT_TXDR			BIT(4)
> +#define SDMMC_INT_DATA_OVER		BIT(3)
> +#define SDMMC_INT_CMD_DONE		BIT(2)
> +#define SDMMC_INT_RESP_ERR		BIT(1)
> +#define SDMMC_INT_CD			BIT(0)
> +#define SDMMC_INT_ERROR			0xbfc2
> +/* Command register defines */
> +#define SDMMC_CMD_START			BIT(31)
> +#define SDMMC_CMD_CCS_EXP		BIT(23)
> +#define SDMMC_CMD_CEATA_RD		BIT(22)
> +#define SDMMC_CMD_UPD_CLK		BIT(21)
> +#define SDMMC_CMD_INIT			BIT(15)
> +#define SDMMC_CMD_STOP			BIT(14)
> +#define SDMMC_CMD_PRV_DAT_WAIT		BIT(13)
> +#define SDMMC_CMD_SEND_STOP		BIT(12)
> +#define SDMMC_CMD_STRM_MODE		BIT(11)
> +#define SDMMC_CMD_DAT_WR		BIT(10)
> +#define SDMMC_CMD_DAT_EXP		BIT(9)
> +#define SDMMC_CMD_RESP_CRC		BIT(8)
> +#define SDMMC_CMD_RESP_LONG		BIT(7)
> +#define SDMMC_CMD_RESP_EXP		BIT(6)
> +#define SDMMC_CMD_INDX(n)		((n) & 0x1F)
> +/* Status register defines */
> +#define SDMMC_GET_FCNT(x)		(((x)>>17) & 0x1FF)
> +#define SDMMC_FIFO_SZ			32
> +/* Internal DMAC interrupt defines */
> +#define SDMMC_IDMAC_INT_AI		BIT(9)
> +#define SDMMC_IDMAC_INT_NI		BIT(8)
> +#define SDMMC_IDMAC_INT_CES		BIT(5)
> +#define SDMMC_IDMAC_INT_DU		BIT(4)
> +#define SDMMC_IDMAC_INT_FBE		BIT(2)
> +#define SDMMC_IDMAC_INT_RI		BIT(1)
> +#define SDMMC_IDMAC_INT_TI		BIT(0)
> +/* Internal DMAC bus mode bits */
> +#define SDMMC_IDMAC_ENABLE		BIT(7)
> +#define SDMMC_IDMAC_FB			BIT(1)
> +#define SDMMC_IDMAC_SWRESET		BIT(0)
> +
> +/* Register access macros */
> +#define mci_readl(dev, reg)			\
> +	__raw_readl(dev->regs + SDMMC_##reg)
> +#define mci_writel(dev, reg, value)			\
> +	__raw_writel((value), dev->regs + SDMMC_##reg)
> +
> +/* 16-bit FIFO access macros */
> +#define mci_readw(dev, reg)			\
> +	__raw_readw(dev->regs + SDMMC_##reg)
> +#define mci_writew(dev, reg, value)			\
> +	__raw_writew((value), dev->regs + SDMMC_##reg)
> +
> +/* 64-bit FIFO access macros */
> +#define mci_readq(dev, reg)			\
> +	__raw_readq(dev->regs + SDMMC_##reg)
> +#define mci_writeq(dev, reg, value)			\
> +	__raw_writeq((value), dev->regs + SDMMC_##reg)
> +
> +#endif /* _DW_MMC_H_ */
> diff --git a/include/linux/mmc/dw_mmc.h b/include/linux/mmc/dw_mmc.h
> new file mode 100644
> index 0000000..d2f92bd
> --- /dev/null
> +++ b/include/linux/mmc/dw_mmc.h
> @@ -0,0 +1,149 @@
> +/*
> + * Synopsys DesignWare Multimedia Card Interface driver
> + *  (Based on NXP driver for lpc 31xx)
> + *
> + * Copyright (C) 2009 NXP Semiconductors
> + * Copyright (C) 2009, 2010 Imagination Technologies Ltd.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + */
> +
> +#ifndef _LINUX_MMC_DW_MMC_H_
> +#define _LINUX_MMC_DW_MMC_H_
> +
> +#define MAX_MCI_SLOTS	2
> +
> +enum dw_mci_state {
> +	STATE_IDLE = 0,
> +	STATE_SENDING_CMD,
> +	STATE_SENDING_DATA,
> +	STATE_DATA_BUSY,
> +	STATE_SENDING_STOP,
> +	STATE_DATA_ERROR,
> +};
> +
> +enum {
> +	EVENT_CMD_COMPLETE = 0,
> +	EVENT_XFER_COMPLETE,
> +	EVENT_DATA_COMPLETE,
> +	EVENT_DATA_ERROR,
> +	EVENT_XFER_ERROR
> +};
> +
> +struct mmc_data;
> +
> +struct dw_mci {
> +	spinlock_t		lock;
> +	void __iomem		*regs;
> +
> +	struct scatterlist	*sg;
> +	unsigned int		pio_offset;
> +
> +	struct dw_mci_slot	*cur_slot;
> +	struct mmc_request	*mrq;
> +	struct mmc_command	*cmd;
> +	struct mmc_data		*data;
> +
> +	/* DMA interface members*/
> +	int			use_dma;
> +
> +	dma_addr_t		sg_dma;
> +	void			*sg_cpu;
> +	struct dw_mci_dma_ops	*dma_ops;
> +#ifdef CONFIG_MMC_DW_IDMAC
> +	unsigned int		ring_size;
> +#else
> +	struct dw_mci_dma_data	*dma_data;
> +#endif
> +	u32			cmd_status;
> +	u32			data_status;
> +	u32			stop_cmdr;
> +	u32			dir_status;
> +	struct tasklet_struct	tasklet;
> +	struct tasklet_struct	card_tasklet;
> +	unsigned long		pending_events;
> +	unsigned long		completed_events;
> +	enum dw_mci_state	state;
> +	struct list_head	queue;
> +
> +	u32			bus_hz;
> +	u32			current_speed;
> +	u32			num_slots;
> +	struct platform_device	*pdev;
> +	struct dw_mci_board	*pdata;
> +	struct dw_mci_slot	*slot[MAX_MCI_SLOTS];
> +
> +	/* FIFO push and pull */
> +	int			data_shift;
> +	void (*push_data)(struct dw_mci *host, void *buf, int cnt);
> +	void (*pull_data)(struct dw_mci *host, void *buf, int cnt);
> +
> +	/* Workaround flags */
> +	u32			quirks;
> +};
> +
> +/* DMA ops for Internal/External DMAC interface */
> +struct dw_mci_dma_ops {
> +	/* DMA Ops */
> +	int (*init)(struct dw_mci *host);
> +	void (*start)(struct dw_mci *host, unsigned int sg_len);
> +	void (*complete)(struct dw_mci *host);
> +	void (*stop)(struct dw_mci *host);
> +	void (*cleanup)(struct dw_mci *host);
> +	void (*exit)(struct dw_mci *host);
> +};
> +
> +/* IP Quirks/flags. */
> +/* No special quirks or flags to cater for */
> +#define DW_MCI_QUIRK_NONE		0

Is this needed?

> +/* DTO fix for command transmission with IDMAC configured */
> +#define DW_MCI_QUIRK_IDMAC_DTO		1
> +/* delay needed between retries on some 2.11a implementations */
> +#define DW_MCI_QUIRK_RETRY_DELAY	2
> +/* High Speed Capable - Supports HS cards (upto 50MHz) */
> +#define DW_MCI_QUIRK_HIGHSPEED		4
> +
> +
> +struct dma_pdata;
> +
> +struct block_settings {
> +	unsigned short	max_segs;	/* see blk_queue_max_segments */
> +	unsigned int	max_blk_size;	/* maximum size of one mmc block */
> +	unsigned int	max_blk_count;	/* maximum number of blocks in one req*/
> +	unsigned int	max_req_size;	/* maximum number of bytes in one req*/
> +	unsigned int	max_seg_size;	/* see blk_queue_max_segment_size */
> +};
> +
> +/* Board platform data */
> +struct dw_mci_board {
> +	u32 num_slots;
> +
> +	u32 quirks; /* Workaround / Quirk flags */
> +	unsigned long bus_hz; /* Bus speed */
> +
> +	/* delay in mS before detecting cards after interrupt */
> +	u32 detect_delay_ms;
> +
> +	int (*init)(u32 slot_id, irq_handler_t , void *);
> +	int (*get_ro)(u32 slot_id);
> +	int (*get_cd)(u32 slot_id);
> +	int (*get_ocr)(u32 slot_id);
> +	int (*get_bus_wd)(u32 slot_id);
> +	/*
> +	 * Enable power to selected slot and set voltage to desired level.
> +	 * Voltage levels are specified using MMC_VDD_xxx defines defined
> +	 * in linux/mmc/host.h file.
> +	 */
> +	void (*setpower)(u32 slot_id, u32 volt);
> +	void (*exit)(u32 slot_id);
> +	void (*select_slot)(u32 slot_id);
> +
> +	struct dw_mci_dma_ops *dma_ops;
> +	struct dma_pdata *data;
> +	struct block_settings *blk_settings;
> +};
> +
> +#endif /* _LINUX_MMC_DW_MMC_H_ */
> -- 
> 1.7.2.2
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux USB Devel]     [Linux Media]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux