linux/drivers/mmc/host/sh_mmcif.c

// SPDX-License-Identifier: GPL-2.0
/*
 * MMCIF eMMC driver.
 *
 * Copyright (C) 2010 Renesas Solutions Corp.
 * Yusuke Goda <yusuke.goda.sx@renesas.com>
 */

/*
 * The MMCIF driver is now processing MMC requests asynchronously, according
 * to the Linux MMC API requirement.
 *
 * The MMCIF driver processes MMC requests in up to 3 stages: command, optional
 * data, and optional stop. To achieve asynchronous processing each of these
 * stages is split into two halves: a top and a bottom half. The top half
 * initialises the hardware, installs a timeout handler to handle completion
 * timeouts, and returns. In case of the command stage this immediately returns
 * control to the caller, leaving all further processing to run asynchronously.
 * All further request processing is performed by the bottom halves.
 *
 * The bottom half further consists of a "hard" IRQ handler, an IRQ handler
 * thread, a DMA completion callback, if DMA is used, a timeout work, and
 * request- and stage-specific handler methods.
 *
 * Each bottom half run begins with either a hardware interrupt, a DMA callback
 * invocation, or a timeout work run. In case of an error or a successful
 * processing completion, the MMC core is informed and the request processing is
 * finished. In case processing has to continue, i.e., if data has to be read
 * from or written to the card, or if a stop command has to be sent, the next
 * top half is called, which performs the necessary hardware handling and
 * reschedules the timeout work. This returns the driver state machine into the
 * bottom half waiting state.
 */

#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
#include <linux/mmc/card.h>
#include <linux/mmc/core.h>
#include <linux/mmc/host.h>
#include <linux/mmc/mmc.h>
#include <linux/mmc/sdio.h>
#include <linux/mmc/slot-gpio.h>
#include <linux/mod_devicetable.h>
#include <linux/mutex.h>
#include <linux/pagemap.h>
#include <linux/platform_data/sh_mmcif.h>
#include <linux/platform_device.h>
#include <linux/pm_qos.h>
#include <linux/pm_runtime.h>
#include <linux/sh_dma.h>
#include <linux/spinlock.h>
#include <linux/module.h>

#define DRIVER_NAME	"sh_mmcif"

/* CE_CMD_SET */
#define CMD_MASK		0x3f000000
#define CMD_SET_RTYP_NO		((0 << 23) | (0 << 22))
#define CMD_SET_RTYP_6B		((0 << 23) | (1 << 22)) /* R1/R1b/R3/R4/R5 */
#define CMD_SET_RTYP_17B	((1 << 23) | (0 << 22)) /* R2 */
#define CMD_SET_RBSY		(1 << 21) /* R1b */
#define CMD_SET_CCSEN		(1 << 20)
#define CMD_SET_WDAT		(1 << 19) /* 1: on data, 0: no data */
#define CMD_SET_DWEN		(1 << 18) /* 1: write, 0: read */
#define CMD_SET_CMLTE		(1 << 17) /* 1: multi block trans, 0: single */
#define CMD_SET_CMD12EN		(1 << 16) /* 1: CMD12 auto issue */
#define CMD_SET_RIDXC_INDEX	((0 << 15) | (0 << 14)) /* index check */
#define CMD_SET_RIDXC_BITS	((0 << 15) | (1 << 14)) /* check bits check */
#define CMD_SET_RIDXC_NO	((1 << 15) | (0 << 14)) /* no check */
#define CMD_SET_CRC7C		((0 << 13) | (0 << 12)) /* CRC7 check*/
#define CMD_SET_CRC7C_BITS	((0 << 13) | (1 << 12)) /* check bits check*/
#define CMD_SET_CRC7C_INTERNAL	((1 << 13) | (0 << 12)) /* internal CRC7 check*/
#define CMD_SET_CRC16C		(1 << 10) /* 0: CRC16 check*/
#define CMD_SET_CRCSTE		(1 << 8) /* 1: not receive CRC status */
#define CMD_SET_TBIT		(1 << 7) /* 1: tran mission bit "Low" */
#define CMD_SET_OPDM		(1 << 6) /* 1: open/drain */
#define CMD_SET_CCSH		(1 << 5)
#define CMD_SET_DARS		(1 << 2) /* Dual Data Rate */
#define CMD_SET_DATW_1		((0 << 1) | (0 << 0)) /* 1bit */
#define CMD_SET_DATW_4		((0 << 1) | (1 << 0)) /* 4bit */
#define CMD_SET_DATW_8		((1 << 1) | (0 << 0)) /* 8bit */

/* CE_CMD_CTRL */
#define CMD_CTRL_BREAK		(1 << 0)

/* CE_BLOCK_SET */
#define BLOCK_SIZE_MASK		0x0000ffff

/* CE_INT */
#define INT_CCSDE		(1 << 29)
#define INT_CMD12DRE		(1 << 26)
#define INT_CMD12RBE		(1 << 25)
#define INT_CMD12CRE		(1 << 24)
#define INT_DTRANE		(1 << 23)
#define INT_BUFRE		(1 << 22)
#define INT_BUFWEN		(1 << 21)
#define INT_BUFREN		(1 << 20)
#define INT_CCSRCV		(1 << 19)
#define INT_RBSYE		(1 << 17)
#define INT_CRSPE		(1 << 16)
#define INT_CMDVIO		(1 << 15)
#define INT_BUFVIO		(1 << 14)
#define INT_WDATERR		(1 << 11)
#define INT_RDATERR		(1 << 10)
#define INT_RIDXERR		(1 << 9)
#define INT_RSPERR		(1 << 8)
#define INT_CCSTO		(1 << 5)
#define INT_CRCSTO		(1 << 4)
#define INT_WDATTO		(1 << 3)
#define INT_RDATTO		(1 << 2)
#define INT_RBSYTO		(1 << 1)
#define INT_RSPTO		(1 << 0)
#define INT_ERR_STS		(INT_CMDVIO | INT_BUFVIO | INT_WDATERR |  \
				 INT_RDATERR | INT_RIDXERR | INT_RSPERR | \
				 INT_CCSTO | INT_CRCSTO | INT_WDATTO |	  \
				 INT_RDATTO | INT_RBSYTO | INT_RSPTO)

#define INT_ALL			(INT_RBSYE | INT_CRSPE | INT_BUFREN |	 \
				 INT_BUFWEN | INT_CMD12DRE | INT_BUFRE | \
				 INT_DTRANE | INT_CMD12RBE | INT_CMD12CRE)

#define INT_CCS			(INT_CCSTO | INT_CCSRCV | INT_CCSDE)

/* CE_INT_MASK */
#define MASK_ALL		0x00000000
#define MASK_MCCSDE		(1 << 29)
#define MASK_MCMD12DRE		(1 << 26)
#define MASK_MCMD12RBE		(1 << 25)
#define MASK_MCMD12CRE		(1 << 24)
#define MASK_MDTRANE		(1 << 23)
#define MASK_MBUFRE		(1 << 22)
#define MASK_MBUFWEN		(1 << 21)
#define MASK_MBUFREN		(1 << 20)
#define MASK_MCCSRCV		(1 << 19)
#define MASK_MRBSYE		(1 << 17)
#define MASK_MCRSPE		(1 << 16)
#define MASK_MCMDVIO		(1 << 15)
#define MASK_MBUFVIO		(1 << 14)
#define MASK_MWDATERR		(1 << 11)
#define MASK_MRDATERR		(1 << 10)
#define MASK_MRIDXERR		(1 << 9)
#define MASK_MRSPERR		(1 << 8)
#define MASK_MCCSTO		(1 << 5)
#define MASK_MCRCSTO		(1 << 4)
#define MASK_MWDATTO		(1 << 3)
#define MASK_MRDATTO		(1 << 2)
#define MASK_MRBSYTO		(1 << 1)
#define MASK_MRSPTO		(1 << 0)

#define MASK_START_CMD		(MASK_MCMDVIO | MASK_MBUFVIO | MASK_MWDATERR | \
				 MASK_MRDATERR | MASK_MRIDXERR | MASK_MRSPERR | \
				 MASK_MCRCSTO | MASK_MWDATTO | \
				 MASK_MRDATTO | MASK_MRBSYTO | MASK_MRSPTO)

#define MASK_CLEAN		(INT_ERR_STS | MASK_MRBSYE | MASK_MCRSPE |	\
				 MASK_MBUFREN | MASK_MBUFWEN |			\
				 MASK_MCMD12DRE | MASK_MBUFRE | MASK_MDTRANE |	\
				 MASK_MCMD12RBE | MASK_MCMD12CRE)

/* CE_HOST_STS1 */
#define STS1_CMDSEQ		(1 << 31)

/* CE_HOST_STS2 */
#define STS2_CRCSTE		(1 << 31)
#define STS2_CRC16E		(1 << 30)
#define STS2_AC12CRCE		(1 << 29)
#define STS2_RSPCRC7E		(1 << 28)
#define STS2_CRCSTEBE		(1 << 27)
#define STS2_RDATEBE		(1 << 26)
#define STS2_AC12REBE		(1 << 25)
#define STS2_RSPEBE		(1 << 24)
#define STS2_AC12IDXE		(1 << 23)
#define STS2_RSPIDXE		(1 << 22)
#define STS2_CCSTO		(1 << 15)
#define STS2_RDATTO		(1 << 14)
#define STS2_DATBSYTO		(1 << 13)
#define STS2_CRCSTTO		(1 << 12)
#define STS2_AC12BSYTO		(1 << 11)
#define STS2_RSPBSYTO		(1 << 10)
#define STS2_AC12RSPTO		(1 << 9)
#define STS2_RSPTO		(1 << 8)
#define STS2_CRC_ERR		(STS2_CRCSTE | STS2_CRC16E |		\
				 STS2_AC12CRCE | STS2_RSPCRC7E | STS2_CRCSTEBE)
#define STS2_TIMEOUT_ERR	(STS2_CCSTO | STS2_RDATTO |		\
				 STS2_DATBSYTO | STS2_CRCSTTO |		\
				 STS2_AC12BSYTO | STS2_RSPBSYTO |	\
				 STS2_AC12RSPTO | STS2_RSPTO)

#define CLKDEV_EMMC_DATA	52000000 /* 52 MHz */
#define CLKDEV_MMC_DATA		20000000 /* 20 MHz */
#define CLKDEV_INIT		400000   /* 400 kHz */

enum sh_mmcif_state {
	STATE_IDLE,
	STATE_REQUEST,
	STATE_IOS,
	STATE_TIMEOUT,
};

enum sh_mmcif_wait_for {
	MMCIF_WAIT_FOR_REQUEST,
	MMCIF_WAIT_FOR_CMD,
	MMCIF_WAIT_FOR_MREAD,
	MMCIF_WAIT_FOR_MWRITE,
	MMCIF_WAIT_FOR_READ,
	MMCIF_WAIT_FOR_WRITE,
	MMCIF_WAIT_FOR_READ_END,
	MMCIF_WAIT_FOR_WRITE_END,
	MMCIF_WAIT_FOR_STOP,
};

/*
 * difference for each SoC
 */
struct sh_mmcif_host {
	struct mmc_host *mmc;
	struct mmc_request *mrq;
	struct platform_device *pd;
	struct clk *clk;
	int bus_width;
	unsigned char timing;
	bool sd_error;
	bool dying;
	long timeout;
	void __iomem *addr;
	spinlock_t lock;		/* protect sh_mmcif_host::state */
	enum sh_mmcif_state state;
	enum sh_mmcif_wait_for wait_for;
	struct delayed_work timeout_work;
	size_t blocksize;
	struct sg_mapping_iter sg_miter;
	bool power;
	bool ccs_enable;		/* Command Completion Signal support */
	bool clk_ctrl2_enable;
	struct mutex thread_lock;
	u32 clkdiv_map;         /* see CE_CLK_CTRL::CLKDIV */

	/* DMA support */
	struct dma_chan		*chan_rx;
	struct dma_chan		*chan_tx;
	struct completion	dma_complete;
	bool			dma_active;
};

static const struct of_device_id sh_mmcif_of_match[] = {
	{ .compatible = "renesas,sh-mmcif" },
	{ }
};
MODULE_DEVICE_TABLE(of, sh_mmcif_of_match);

#define sh_mmcif_host_to_dev(host) (&host->pd->dev)

static inline void sh_mmcif_bitset(struct sh_mmcif_host *host,
					unsigned int reg, u32 val)
{
	writel(val | readl(host->addr + reg), host->addr + reg);
}

static inline void sh_mmcif_bitclr(struct sh_mmcif_host *host,
					unsigned int reg, u32 val)
{
	writel(~val & readl(host->addr + reg), host->addr + reg);
}

static void sh_mmcif_dma_complete(void *arg)
{
	struct sh_mmcif_host *host = arg;
	struct mmc_request *mrq = host->mrq;
	struct device *dev = sh_mmcif_host_to_dev(host);

	dev_dbg(dev, "Command completed\n");

	if (WARN(!mrq || !mrq->data, "%s: NULL data in DMA completion!\n",
		 dev_name(dev)))
		return;

	complete(&host->dma_complete);
}

static void sh_mmcif_start_dma_rx(struct sh_mmcif_host *host)
{
	struct mmc_data *data = host->mrq->data;
	struct scatterlist *sg = data->sg;
	struct dma_async_tx_descriptor *desc = NULL;
	struct dma_chan *chan = host->chan_rx;
	struct device *dev = sh_mmcif_host_to_dev(host);
	dma_cookie_t cookie = -EINVAL;
	int ret;

	ret = dma_map_sg(chan->device->dev, sg, data->sg_len,
			 DMA_FROM_DEVICE);
	if (ret > 0) {
		host->dma_active = true;
		desc = dmaengine_prep_slave_sg(chan, sg, ret,
			DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
	}

	if (desc) {
		desc->callback = sh_mmcif_dma_complete;
		desc->callback_param = host;
		cookie = dmaengine_submit(desc);
		sh_mmcif_bitset(host, MMCIF_CE_BUF_ACC, BUF_ACC_DMAREN);
		dma_async_issue_pending(chan);
	}
	dev_dbg(dev, "%s(): mapped %d -> %d, cookie %d\n",
		__func__, data->sg_len, ret, cookie);

	if (!desc) {
		/* DMA failed, fall back to PIO */
		if (ret >= 0)
			ret = -EIO;
		host->chan_rx = NULL;
		host->dma_active = false;
		dma_release_channel(chan);
		/* Free the Tx channel too */
		chan = host->chan_tx;
		if (chan) {
			host->chan_tx = NULL;
			dma_release_channel(chan);
		}
		dev_warn(dev,
			 "DMA failed: %d, falling back to PIO\n", ret);
		sh_mmcif_bitclr(host, MMCIF_CE_BUF_ACC, BUF_ACC_DMAREN | BUF_ACC_DMAWEN);
	}

	dev_dbg(dev, "%s(): desc %p, cookie %d, sg[%d]\n", __func__,
		desc, cookie, data->sg_len);
}

static void sh_mmcif_start_dma_tx(struct sh_mmcif_host *host)
{
	struct mmc_data *data = host->mrq->data;
	struct scatterlist *sg = data->sg;
	struct dma_async_tx_descriptor *desc = NULL;
	struct dma_chan *chan = host->chan_tx;
	struct device *dev = sh_mmcif_host_to_dev(host);
	dma_cookie_t cookie = -EINVAL;
	int ret;

	ret = dma_map_sg(chan->device->dev, sg, data->sg_len,
			 DMA_TO_DEVICE);
	if (ret > 0) {
		host->dma_active = true;
		desc = dmaengine_prep_slave_sg(chan, sg, ret,
			DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
	}

	if (desc) {
		desc->callback = sh_mmcif_dma_complete;
		desc->callback_param = host;
		cookie = dmaengine_submit(desc);
		sh_mmcif_bitset(host, MMCIF_CE_BUF_ACC, BUF_ACC_DMAWEN);
		dma_async_issue_pending(chan);
	}
	dev_dbg(dev, "%s(): mapped %d -> %d, cookie %d\n",
		__func__, data->sg_len, ret, cookie);

	if (!desc) {
		/* DMA failed, fall back to PIO */
		if (ret >= 0)
			ret = -EIO;
		host->chan_tx = NULL;
		host->dma_active = false;
		dma_release_channel(chan);
		/* Free the Rx channel too */
		chan = host->chan_rx;
		if (chan) {
			host->chan_rx = NULL;
			dma_release_channel(chan);
		}
		dev_warn(dev,
			 "DMA failed: %d, falling back to PIO\n", ret);
		sh_mmcif_bitclr(host, MMCIF_CE_BUF_ACC, BUF_ACC_DMAREN | BUF_ACC_DMAWEN);
	}

	dev_dbg(dev, "%s(): desc %p, cookie %d\n", __func__,
		desc, cookie);
}

static struct dma_chan *
sh_mmcif_request_dma_pdata(struct sh_mmcif_host *host, uintptr_t slave_id)
{
	dma_cap_mask_t mask;

	dma_cap_zero(mask);
	dma_cap_set(DMA_SLAVE, mask);
	if (slave_id <= 0)
		return NULL;

	return dma_request_channel(mask, shdma_chan_filter, (void *)slave_id);
}

static int sh_mmcif_dma_slave_config(struct sh_mmcif_host *host,
				     struct dma_chan *chan,
				     enum dma_transfer_direction direction)
{
	struct resource *res;
	struct dma_slave_config cfg = { 0, };

	res = platform_get_resource(host->pd, IORESOURCE_MEM, 0);
	if (!res)
		return -EINVAL;

	cfg.direction = direction;

	if (direction == DMA_DEV_TO_MEM) {
		cfg.src_addr = res->start + MMCIF_CE_DATA;
		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
	} else {
		cfg.dst_addr = res->start + MMCIF_CE_DATA;
		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
	}

	return dmaengine_slave_config(chan, &cfg);
}

static void sh_mmcif_request_dma(struct sh_mmcif_host *host)
{
	struct device *dev = sh_mmcif_host_to_dev(host);
	host->dma_active = false;

	/* We can only either use DMA for both Tx and Rx or not use it at all */
	if (IS_ENABLED(CONFIG_SUPERH) && dev->platform_data) {
		struct sh_mmcif_plat_data *pdata = dev->platform_data;

		host->chan_tx = sh_mmcif_request_dma_pdata(host,
							pdata->slave_id_tx);
		host->chan_rx = sh_mmcif_request_dma_pdata(host,
							pdata->slave_id_rx);
	} else {
		host->chan_tx = dma_request_chan(dev, "tx");
		if (IS_ERR(host->chan_tx))
			host->chan_tx = NULL;
		host->chan_rx = dma_request_chan(dev, "rx");
		if (IS_ERR(host->chan_rx))
			host->chan_rx = NULL;
	}
	dev_dbg(dev, "%s: got channel TX %p RX %p\n", __func__, host->chan_tx,
		host->chan_rx);

	if (!host->chan_tx || !host->chan_rx ||
	    sh_mmcif_dma_slave_config(host, host->chan_tx, DMA_MEM_TO_DEV) ||
	    sh_mmcif_dma_slave_config(host, host->chan_rx, DMA_DEV_TO_MEM))
		goto error;

	return;

error:
	if (host->chan_tx)
		dma_release_channel(host->chan_tx);
	if (host->chan_rx)
		dma_release_channel(host->chan_rx);
	host->chan_tx = host->chan_rx = NULL;
}

static void sh_mmcif_release_dma(struct sh_mmcif_host *host)
{
	sh_mmcif_bitclr(host, MMCIF_CE_BUF_ACC, BUF_ACC_DMAREN | BUF_ACC_DMAWEN);
	/* Descriptors are freed automatically */
	if (host->chan_tx) {
		struct dma_chan *chan = host->chan_tx;
		host->chan_tx = NULL;
		dma_release_channel(chan);
	}
	if (host->chan_rx) {
		struct dma_chan *chan = host->chan_rx;
		host->chan_rx = NULL;
		dma_release_channel(chan);
	}

	host->dma_active = false;
}

static void sh_mmcif_clock_control(struct sh_mmcif_host *host, unsigned int clk)
{
	struct device *dev = sh_mmcif_host_to_dev(host);
	struct sh_mmcif_plat_data *p = dev->platform_data;
	bool sup_pclk = p ? p->sup_pclk : false;
	unsigned int current_clk = clk_get_rate(host->clk);
	unsigned int clkdiv;

	sh_mmcif_bitclr(host, MMCIF_CE_CLK_CTRL, CLK_ENABLE);
	sh_mmcif_bitclr(host, MMCIF_CE_CLK_CTRL, CLK_CLEAR);

	if (!clk)
		return;

	if (host->clkdiv_map) {
		unsigned int freq, best_freq, myclk, div, diff_min, diff;
		int i;

		clkdiv = 0;
		diff_min = ~0;
		best_freq = 0;
		for (i = 31; i >= 0; i--) {
			if (!((1 << i) & host->clkdiv_map))
				continue;

			/*
			 * clk = parent_freq / div
			 * -> parent_freq = clk x div
			 */

			div = 1 << (i + 1);
			freq = clk_round_rate(host->clk, clk * div);
			myclk = freq / div;
			diff = (myclk > clk) ? myclk - clk : clk - myclk;

			if (diff <= diff_min) {
				best_freq = freq;
				clkdiv = i;
				diff_min = diff;
			}
		}

		dev_dbg(dev, "clk %u/%u (%u, 0x%x)\n",
			(best_freq >> (clkdiv + 1)), clk, best_freq, clkdiv);

		clk_set_rate(host->clk, best_freq);
		clkdiv = clkdiv << 16;
	} else if (sup_pclk && clk == current_clk) {
		clkdiv = CLK_SUP_PCLK;
	} else {
		clkdiv = (fls(DIV_ROUND_UP(current_clk, clk) - 1) - 1) << 16;
	}

	sh_mmcif_bitset(host, MMCIF_CE_CLK_CTRL, CLK_CLEAR & clkdiv);
	sh_mmcif_bitset(host, MMCIF_CE_CLK_CTRL, CLK_ENABLE);
}

static void sh_mmcif_sync_reset(struct sh_mmcif_host *host)
{
	u32 tmp;

	tmp = 0x010f0000 & sh_mmcif_readl(host->addr, MMCIF_CE_CLK_CTRL);

	sh_mmcif_writel(host->addr, MMCIF_CE_VERSION, SOFT_RST_ON);
	sh_mmcif_writel(host->addr, MMCIF_CE_VERSION, SOFT_RST_OFF);
	if (host->ccs_enable)
		tmp |= SCCSTO_29;
	if (host->clk_ctrl2_enable)
		sh_mmcif_writel(host->addr, MMCIF_CE_CLK_CTRL2, 0x0F0F0000);
	sh_mmcif_bitset(host, MMCIF_CE_CLK_CTRL, tmp |
		SRSPTO_256 | SRBSYTO_29 | SRWDTO_29);
	/* byte swap on */
	sh_mmcif_bitset(host, MMCIF_CE_BUF_ACC, BUF_ACC_ATYP);
}

static int sh_mmcif_error_manage(struct sh_mmcif_host *host)
{
	struct device *dev = sh_mmcif_host_to_dev(host);
	u32 state1, state2;
	int ret, timeout;

	host->sd_error = false;

	state1 = sh_mmcif_readl(host->addr, MMCIF_CE_HOST_STS1);
	state2 = sh_mmcif_readl(host->addr, MMCIF_CE_HOST_STS2);
	dev_dbg(dev, "ERR HOST_STS1 = %08x\n", state1);
	dev_dbg(dev, "ERR HOST_STS2 = %08x\n", state2);

	if (state1 & STS1_CMDSEQ) {
		sh_mmcif_bitset(host, MMCIF_CE_CMD_CTRL, CMD_CTRL_BREAK);
		sh_mmcif_bitset(host, MMCIF_CE_CMD_CTRL, ~CMD_CTRL_BREAK);
		for (timeout = 10000; timeout; timeout--) {
			if (!(sh_mmcif_readl(host->addr, MMCIF_CE_HOST_STS1)
			      & STS1_CMDSEQ))
				break;
			mdelay(1);
		}
		if (!timeout) {
			dev_err(dev,
				"Forced end of command sequence timeout err\n");
			return -EIO;
		}
		sh_mmcif_sync_reset(host);
		dev_dbg(dev, "Forced end of command sequence\n");
		return -EIO;
	}

	if (state2 & STS2_CRC_ERR) {
		dev_err(dev, " CRC error: state %u, wait %u\n",
			host->state, host->wait_for);
		ret = -EIO;
	} else if (state2 & STS2_TIMEOUT_ERR) {
		dev_err(dev, " Timeout: state %u, wait %u\n",
			host->state, host->wait_for);
		ret = -ETIMEDOUT;
	} else {
		dev_dbg(dev, " End/Index error: state %u, wait %u\n",
			host->state, host->wait_for);
		ret = -EIO;
	}
	return ret;
}

static void sh_mmcif_single_read(struct sh_mmcif_host *host,
				 struct mmc_request *mrq)
{
	struct mmc_data *data = mrq->data;

	host->blocksize = (sh_mmcif_readl(host->addr, MMCIF_CE_BLOCK_SET) &
			   BLOCK_SIZE_MASK) + 3;

	sg_miter_start(&host->sg_miter, data->sg, data->sg_len,
		       SG_MITER_TO_SG);

	host->wait_for = MMCIF_WAIT_FOR_READ;

	/* buf read enable */
	sh_mmcif_bitset(host, MMCIF_CE_INT_MASK, MASK_MBUFREN);
}

static bool sh_mmcif_read_block(struct sh_mmcif_host *host)
{
	struct sg_mapping_iter *sgm = &host->sg_miter;
	struct device *dev = sh_mmcif_host_to_dev(host);
	struct mmc_data *data = host->mrq->data;
	u32 *p;
	int i;

	if (host->sd_error) {
		sg_miter_stop(sgm);
		data->error = sh_mmcif_error_manage(host);
		dev_dbg(dev, "%s(): %d\n", __func__, data->error);
		return false;
	}

	if (!sg_miter_next(sgm)) {
		/* This should not happen on single blocks */
		sg_miter_stop(sgm);
		return false;
	}

	p = sgm->addr;

	for (i = 0; i < host->blocksize / 4; i++)
		*p++ = sh_mmcif_readl(host->addr, MMCIF_CE_DATA);

	sg_miter_stop(&host->sg_miter);

	/* buffer read end */
	sh_mmcif_bitset(host, MMCIF_CE_INT_MASK, MASK_MBUFRE);
	host->wait_for = MMCIF_WAIT_FOR_READ_END;

	return true;
}

static void sh_mmcif_multi_read(struct sh_mmcif_host *host,
				struct mmc_request *mrq)
{
	struct sg_mapping_iter *sgm = &host->sg_miter;
	struct mmc_data *data = mrq->data;

	if (!data->sg_len || !data->sg->length)
		return;

	host->blocksize = sh_mmcif_readl(host->addr, MMCIF_CE_BLOCK_SET) &
		BLOCK_SIZE_MASK;

	sg_miter_start(sgm, data->sg, data->sg_len,
		       SG_MITER_TO_SG);

	/* Advance to the first sglist entry */
	if (!sg_miter_next(sgm)) {
		sg_miter_stop(sgm);
		return;
	}

	host->wait_for = MMCIF_WAIT_FOR_MREAD;

	sh_mmcif_bitset(host, MMCIF_CE_INT_MASK, MASK_MBUFREN);
}

static bool sh_mmcif_mread_block(struct sh_mmcif_host *host)
{
	struct sg_mapping_iter *sgm = &host->sg_miter;
	struct device *dev = sh_mmcif_host_to_dev(host);
	struct mmc_data *data = host->mrq->data;
	u32 *p;
	int i;

	if (host->sd_error) {
		sg_miter_stop(sgm);
		data->error = sh_mmcif_error_manage(host);
		dev_dbg(dev, "%s(): %d\n", __func__, data->error);
		return false;
	}

	p = sgm->addr;

	for (i = 0; i < host->blocksize / 4; i++)
		*p++ = sh_mmcif_readl(host->addr, MMCIF_CE_DATA);

	sgm->consumed = host->blocksize;

	sh_mmcif_bitset(host, MMCIF_CE_INT_MASK, MASK_MBUFREN);

	if (!sg_miter_next(sgm)) {
		sg_miter_stop(sgm);
		return false;
	}

	return true;
}

static void sh_mmcif_single_write(struct sh_mmcif_host *host,
					struct mmc_request *mrq)
{
	struct mmc_data *data = mrq->data;

	host->blocksize = (sh_mmcif_readl(host->addr, MMCIF_CE_BLOCK_SET) &
			   BLOCK_SIZE_MASK) + 3;

	sg_miter_start(&host->sg_miter, data->sg, data->sg_len,
		       SG_MITER_FROM_SG);

	host->wait_for = MMCIF_WAIT_FOR_WRITE;

	/* buf write enable */
	sh_mmcif_bitset(host, MMCIF_CE_INT_MASK, MASK_MBUFWEN);
}

static bool sh_mmcif_write_block(struct sh_mmcif_host *host)
{
	struct sg_mapping_iter *sgm = &host->sg_miter;
	struct device *dev = sh_mmcif_host_to_dev(host);
	struct mmc_data *data = host->mrq->data;
	u32 *p;
	int i;

	if (host->sd_error) {
		sg_miter_stop(sgm);
		data->error = sh_mmcif_error_manage(host);
		dev_dbg(dev, "%s(): %d\n", __func__, data->error);
		return false;
	}

	if (!sg_miter_next(sgm)) {
		/* This should not happen on single blocks */
		sg_miter_stop(sgm);
		return false;
	}

	p = sgm->addr;

	for (i = 0; i < host->blocksize / 4; i++)
		sh_mmcif_writel(host->addr, MMCIF_CE_DATA, *p++);

	sg_miter_stop(&host->sg_miter);

	/* buffer write end */
	sh_mmcif_bitset(host, MMCIF_CE_INT_MASK, MASK_MDTRANE);
	host->wait_for = MMCIF_WAIT_FOR_WRITE_END;

	return true;
}

static void sh_mmcif_multi_write(struct sh_mmcif_host *host,
				struct mmc_request *mrq)
{
	struct sg_mapping_iter *sgm = &host->sg_miter;
	struct mmc_data *data = mrq->data;

	if (!data->sg_len || !data->sg->length)
		return;

	host->blocksize = sh_mmcif_readl(host->addr, MMCIF_CE_BLOCK_SET) &
		BLOCK_SIZE_MASK;

	sg_miter_start(sgm, data->sg, data->sg_len,
		       SG_MITER_FROM_SG);

	/* Advance to the first sglist entry */
	if (!sg_miter_next(sgm)) {
		sg_miter_stop(sgm);
		return;
	}

	host->wait_for = MMCIF_WAIT_FOR_MWRITE;

	sh_mmcif_bitset(host, MMCIF_CE_INT_MASK, MASK_MBUFWEN);
}

static bool sh_mmcif_mwrite_block(struct sh_mmcif_host *host)
{
	struct sg_mapping_iter *sgm = &host->sg_miter;
	struct device *dev = sh_mmcif_host_to_dev(host);
	struct mmc_data *data = host->mrq->data;
	u32 *p;
	int i;

	if (host->sd_error) {
		sg_miter_stop(sgm);
		data->error = sh_mmcif_error_manage(host);
		dev_dbg(dev, "%s(): %d\n", __func__, data->error);
		return false;
	}

	p = sgm->addr;

	for (i = 0; i < host->blocksize / 4; i++)
		sh_mmcif_writel(host->addr, MMCIF_CE_DATA, *p++);

	sgm->consumed = host->blocksize;

	if (!sg_miter_next(sgm)) {
		sg_miter_stop(sgm);
		return false;
	}

	sh_mmcif_bitset(host, MMCIF_CE_INT_MASK, MASK_MBUFWEN);

	return true;
}

static void sh_mmcif_get_response(struct sh_mmcif_host *host,
						struct mmc_command *cmd)
{
	if (cmd->flags & MMC_RSP_136) {
		cmd->resp[0] = sh_mmcif_readl(host->addr, MMCIF_CE_RESP3);
		cmd->resp[1] = sh_mmcif_readl(host->addr, MMCIF_CE_RESP2);
		cmd->resp[2] = sh_mmcif_readl(host->addr, MMCIF_CE_RESP1);
		cmd->resp[3] = sh_mmcif_readl(host->addr, MMCIF_CE_RESP0);
	} else
		cmd->resp[0] = sh_mmcif_readl(host->addr, MMCIF_CE_RESP0);
}

static void sh_mmcif_get_cmd12response(struct sh_mmcif_host *host,
						struct mmc_command *cmd)
{
	cmd->resp[0] = sh_mmcif_readl(host->addr, MMCIF_CE_RESP_CMD12);
}

static u32 sh_mmcif_set_cmd(struct sh_mmcif_host *host,
			    struct mmc_request *mrq)
{
	struct device *dev = sh_mmcif_host_to_dev(host);
	struct mmc_data *data = mrq->data;
	struct mmc_command *cmd = mrq->cmd;
	u32 opc = cmd->opcode;
	u32 tmp = 0;

	/* Response Type check */
	switch (mmc_resp_type(cmd)) {
	case MMC_RSP_NONE:
		tmp |= CMD_SET_RTYP_NO;
		break;
	case MMC_RSP_R1:
	case MMC_RSP_R3:
		tmp |= CMD_SET_RTYP_6B;
		break;
	case MMC_RSP_R1B:
		tmp |= CMD_SET_RBSY | CMD_SET_RTYP_6B;
		break;
	case MMC_RSP_R2:
		tmp |= CMD_SET_RTYP_17B;
		break;
	default:
		dev_err(dev, "Unsupported response type.\n");
		break;
	}

	/* WDAT / DATW */
	if (data) {
		tmp |= CMD_SET_WDAT;
		switch (host->bus_width) {
		case MMC_BUS_WIDTH_1:
			tmp |= CMD_SET_DATW_1;
			break;
		case MMC_BUS_WIDTH_4:
			tmp |= CMD_SET_DATW_4;
			break;
		case MMC_BUS_WIDTH_8:
			tmp |= CMD_SET_DATW_8;
			break;
		default:
			dev_err(dev, "Unsupported bus width.\n");
			break;
		}
		switch (host->timing) {
		case MMC_TIMING_MMC_DDR52:
			/*
			 * MMC core will only set this timing, if the host
			 * advertises the MMC_CAP_1_8V_DDR/MMC_CAP_1_2V_DDR
			 * capability. MMCIF implementations with this
			 * capability, e.g. sh73a0, will have to set it
			 * in their platform data.
			 */
			tmp |= CMD_SET_DARS;
			break;
		}
	}
	/* DWEN */
	if (opc == MMC_WRITE_BLOCK || opc == MMC_WRITE_MULTIPLE_BLOCK)
		tmp |= CMD_SET_DWEN;
	/* CMLTE/CMD12EN */
	if (opc == MMC_READ_MULTIPLE_BLOCK || opc == MMC_WRITE_MULTIPLE_BLOCK) {
		tmp |= CMD_SET_CMLTE | CMD_SET_CMD12EN;
		sh_mmcif_bitset(host, MMCIF_CE_BLOCK_SET,
				data->blocks << 16);
	}
	/* RIDXC[1:0] check bits */
	if (opc == MMC_SEND_OP_COND || opc == MMC_ALL_SEND_CID ||
	    opc == MMC_SEND_CSD || opc == MMC_SEND_CID)
		tmp |= CMD_SET_RIDXC_BITS;
	/* RCRC7C[1:0] check bits */
	if (opc == MMC_SEND_OP_COND)
		tmp |= CMD_SET_CRC7C_BITS;
	/* RCRC7C[1:0] internal CRC7 */
	if (opc == MMC_ALL_SEND_CID ||
		opc == MMC_SEND_CSD || opc == MMC_SEND_CID)
		tmp |= CMD_SET_CRC7C_INTERNAL;

	return (opc << 24) | tmp;
}

static int sh_mmcif_data_trans(struct sh_mmcif_host *host,
			       struct mmc_request *mrq, u32 opc)
{
	struct device *dev = sh_mmcif_host_to_dev(host);

	switch (opc) {
	case MMC_READ_MULTIPLE_BLOCK:
		sh_mmcif_multi_read(host, mrq);
		return 0;
	case MMC_WRITE_MULTIPLE_BLOCK:
		sh_mmcif_multi_write(host, mrq);
		return 0;
	case MMC_WRITE_BLOCK:
		sh_mmcif_single_write(host, mrq);
		return 0;
	case MMC_READ_SINGLE_BLOCK:
	case MMC_SEND_EXT_CSD:
		sh_mmcif_single_read(host, mrq);
		return 0;
	default:
		dev_err(dev, "Unsupported CMD%d\n", opc);
		return -EINVAL;
	}
}

static void sh_mmcif_start_cmd(struct sh_mmcif_host *host,
			       struct mmc_request *mrq)
{
	struct mmc_command *cmd = mrq->cmd;
	u32 opc;
	u32 mask = 0;
	unsigned long flags;

	if (cmd->flags & MMC_RSP_BUSY)
		mask = MASK_START_CMD | MASK_MRBSYE;
	else
		mask = MASK_START_CMD | MASK_MCRSPE;

	if (host->ccs_enable)
		mask |= MASK_MCCSTO;

	if (mrq->data) {
		sh_mmcif_writel(host->addr, MMCIF_CE_BLOCK_SET, 0);
		sh_mmcif_writel(host->addr, MMCIF_CE_BLOCK_SET,
				mrq->data->blksz);
	}
	opc = sh_mmcif_set_cmd(host, mrq);

	if (host->ccs_enable)
		sh_mmcif_writel(host->addr, MMCIF_CE_INT, 0xD80430C0);
	else
		sh_mmcif_writel(host->addr, MMCIF_CE_INT, 0xD80430C0 | INT_CCS);
	sh_mmcif_writel(host->addr, MMCIF_CE_INT_MASK, mask);
	/* set arg */
	sh_mmcif_writel(host->addr, MMCIF_CE_ARG, cmd->arg);
	/* set cmd */
	spin_lock_irqsave(&host->lock, flags);
	sh_mmcif_writel(host->addr, MMCIF_CE_CMD_SET, opc);

	host->wait_for = MMCIF_WAIT_FOR_CMD;
	schedule_delayed_work(&host->timeout_work, host->timeout);
	spin_unlock_irqrestore(&host->lock, flags);
}

static void sh_mmcif_stop_cmd(struct sh_mmcif_host *host,
			      struct mmc_request *mrq)
{
	struct device *dev = sh_mmcif_host_to_dev(host);

	switch (mrq->cmd->opcode) {
	case MMC_READ_MULTIPLE_BLOCK:
		sh_mmcif_bitset(host, MMCIF_CE_INT_MASK, MASK_MCMD12DRE);
		break;
	case MMC_WRITE_MULTIPLE_BLOCK:
		sh_mmcif_bitset(host, MMCIF_CE_INT_MASK, MASK_MCMD12RBE);
		break;
	default:
		dev_err(dev, "unsupported stop cmd\n");
		mrq->stop->error = sh_mmcif_error_manage(host);
		return;
	}

	host->wait_for = MMCIF_WAIT_FOR_STOP;
}

static void sh_mmcif_request(struct mmc_host *mmc, struct mmc_request *mrq)
{
	struct sh_mmcif_host *host = mmc_priv(mmc);
	struct device *dev = sh_mmcif_host_to_dev(host);
	unsigned long flags;

	spin_lock_irqsave(&host->lock, flags);
	if (host->state != STATE_IDLE) {
		dev_dbg(dev, "%s() rejected, state %u\n",
			__func__, host->state);
		spin_unlock_irqrestore(&host->lock, flags);
		mrq->cmd->error = -EAGAIN;
		mmc_request_done(mmc, mrq);
		return;
	}

	host->state = STATE_REQUEST;
	spin_unlock_irqrestore(&host->lock, flags);

	host->mrq = mrq;

	sh_mmcif_start_cmd(host, mrq);
}

static void sh_mmcif_clk_setup(struct sh_mmcif_host *host)
{
	struct device *dev = sh_mmcif_host_to_dev(host);

	if (host->mmc->f_max) {
		unsigned int f_max, f_min = 0, f_min_old;

		f_max = host->mmc->f_max;
		for (f_min_old = f_max; f_min_old > 2;) {
			f_min = clk_round_rate(host->clk, f_min_old / 2);
			if (f_min == f_min_old)
				break;
			f_min_old = f_min;
		}

		/*
		 * This driver assumes this SoC is R-Car Gen2 or later
		 */
		host->clkdiv_map = 0x3ff;

		host->mmc->f_max = f_max >> ffs(host->clkdiv_map);
		host->mmc->f_min = f_min >> fls(host->clkdiv_map);
	} else {
		unsigned int clk = clk_get_rate(host->clk);

		host->mmc->f_max = clk / 2;
		host->mmc->f_min = clk / 512;
	}

	dev_dbg(dev, "clk max/min = %d/%d\n",
		host->mmc->f_max, host->mmc->f_min);
}

static void sh_mmcif_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
	struct sh_mmcif_host *host = mmc_priv(mmc);
	struct device *dev = sh_mmcif_host_to_dev(host);
	unsigned long flags;

	spin_lock_irqsave(&host->lock, flags);
	if (host->state != STATE_IDLE) {
		dev_dbg(dev, "%s() rejected, state %u\n",
			__func__, host->state);
		spin_unlock_irqrestore(&host->lock, flags);
		return;
	}

	host->state = STATE_IOS;
	spin_unlock_irqrestore(&host->lock, flags);

	switch (ios->power_mode) {
	case MMC_POWER_UP:
		if (!IS_ERR(mmc->supply.vmmc))
			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, ios->vdd);
		if (!host->power) {
			clk_prepare_enable(host->clk);
			pm_runtime_get_sync(dev);
			sh_mmcif_sync_reset(host);
			sh_mmcif_request_dma(host);
			host->power = true;
		}
		break;
	case MMC_POWER_OFF:
		if (!IS_ERR(mmc->supply.vmmc))
			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
		if (host->power) {
			sh_mmcif_clock_control(host, 0);
			sh_mmcif_release_dma(host);
			pm_runtime_put(dev);
			clk_disable_unprepare(host->clk);
			host->power = false;
		}
		break;
	case MMC_POWER_ON:
		sh_mmcif_clock_control(host, ios->clock);
		break;
	}

	host->timing = ios->timing;
	host->bus_width = ios->bus_width;
	host->state = STATE_IDLE;
}

static const struct mmc_host_ops sh_mmcif_ops = {
	.request	= sh_mmcif_request,
	.set_ios	= sh_mmcif_set_ios,
	.get_cd		= mmc_gpio_get_cd,
};

static bool sh_mmcif_end_cmd(struct sh_mmcif_host *host)
{
	struct mmc_command *cmd = host->mrq->cmd;
	struct mmc_data *data = host->mrq->data;
	struct device *dev = sh_mmcif_host_to_dev(host);
	long time;

	if (host->sd_error) {
		switch (cmd->opcode) {
		case MMC_ALL_SEND_CID:
		case MMC_SELECT_CARD:
		case MMC_APP_CMD:
			cmd->error = -ETIMEDOUT;
			break;
		default:
			cmd->error = sh_mmcif_error_manage(host);
			break;
		}
		dev_dbg(dev, "CMD%d error %d\n",
			cmd->opcode, cmd->error);
		host->sd_error = false;
		return false;
	}
	if (!(cmd->flags & MMC_RSP_PRESENT)) {
		cmd->error = 0;
		return false;
	}

	sh_mmcif_get_response(host, cmd);

	if (!data)
		return false;

	/*
	 * Completion can be signalled from DMA callback and error, so, have to
	 * reset here, before setting .dma_active
	 */
	init_completion(&host->dma_complete);

	if (data->flags & MMC_DATA_READ) {
		if (host->chan_rx)
			sh_mmcif_start_dma_rx(host);
	} else {
		if (host->chan_tx)
			sh_mmcif_start_dma_tx(host);
	}

	if (!host->dma_active) {
		data->error = sh_mmcif_data_trans(host, host->mrq, cmd->opcode);
		return !data->error;
	}

	/* Running in the IRQ thread, can sleep */
	time = wait_for_completion_interruptible_timeout(&host->dma_complete,
							 host->timeout);

	if (data->flags & MMC_DATA_READ)
		dma_unmap_sg(host->chan_rx->device->dev,
			     data->sg, data->sg_len,
			     DMA_FROM_DEVICE);
	else
		dma_unmap_sg(host->chan_tx->device->dev,
			     data->sg, data->sg_len,
			     DMA_TO_DEVICE);

	if (host->sd_error) {
		dev_err(host->mmc->parent,
			"Error IRQ while waiting for DMA completion!\n");
		/* Woken up by an error IRQ: abort DMA */
		data->error = sh_mmcif_error_manage(host);
	} else if (!time) {
		dev_err(host->mmc->parent, "DMA timeout!\n");
		data->error = -ETIMEDOUT;
	} else if (time < 0) {
		dev_err(host->mmc->parent,
			"wait_for_completion_...() error %ld!\n", time);
		data->error = time;
	}
	sh_mmcif_bitclr(host, MMCIF_CE_BUF_ACC,
			BUF_ACC_DMAREN | BUF_ACC_DMAWEN);
	host->dma_active = false;

	if (data->error) {
		data->bytes_xfered = 0;
		/* Abort DMA */
		if (data->flags & MMC_DATA_READ)
			dmaengine_terminate_sync(host->chan_rx);
		else
			dmaengine_terminate_sync(host->chan_tx);
	}

	return false;
}

static irqreturn_t sh_mmcif_irqt(int irq, void *dev_id)
{
	struct sh_mmcif_host *host = dev_id;
	struct mmc_request *mrq;
	struct device *dev = sh_mmcif_host_to_dev(host);
	bool wait = false;
	unsigned long flags;
	int wait_work;

	spin_lock_irqsave(&host->lock, flags);
	wait_work = host->wait_for;
	spin_unlock_irqrestore(&host->lock, flags);

	cancel_delayed_work_sync(&host->timeout_work);

	mutex_lock(&host->thread_lock);

	mrq = host->mrq;
	if (!mrq) {
		dev_dbg(dev, "IRQ thread state %u, wait %u: NULL mrq!\n",
			host->state, host->wait_for);
		mutex_unlock(&host->thread_lock);
		return IRQ_HANDLED;
	}

	/*
	 * All handlers return true, if processing continues, and false, if the
	 * request has to be completed - successfully or not
	 */
	switch (wait_work) {
	case MMCIF_WAIT_FOR_REQUEST:
		/* We're too late, the timeout has already kicked in */
		mutex_unlock(&host->thread_lock);
		return IRQ_HANDLED;
	case MMCIF_WAIT_FOR_CMD:
		/* Wait for data? */
		wait = sh_mmcif_end_cmd(host);
		break;
	case MMCIF_WAIT_FOR_MREAD:
		/* Wait for more data? */
		wait = sh_mmcif_mread_block(host);
		break;
	case MMCIF_WAIT_FOR_READ:
		/* Wait for data end? */
		wait = sh_mmcif_read_block(host);
		break;
	case MMCIF_WAIT_FOR_MWRITE:
		/* Wait data to write? */
		wait = sh_mmcif_mwrite_block(host);
		break;
	case MMCIF_WAIT_FOR_WRITE:
		/* Wait for data end? */
		wait = sh_mmcif_write_block(host);
		break;
	case MMCIF_WAIT_FOR_STOP:
		if (host->sd_error) {
			mrq->stop->error = sh_mmcif_error_manage(host);
			dev_dbg(dev, "%s(): %d\n", __func__, mrq->stop->error);
			break;
		}
		sh_mmcif_get_cmd12response(host, mrq->stop);
		mrq->stop->error = 0;
		break;
	case MMCIF_WAIT_FOR_READ_END:
	case MMCIF_WAIT_FOR_WRITE_END:
		if (host->sd_error) {
			mrq->data->error = sh_mmcif_error_manage(host);
			dev_dbg(dev, "%s(): %d\n", __func__, mrq->data->error);
		}
		break;
	default:
		BUG();
	}

	if (wait) {
		schedule_delayed_work(&host->timeout_work, host->timeout);
		/* Wait for more data */
		mutex_unlock(&host->thread_lock);
		return IRQ_HANDLED;
	}

	if (host->wait_for != MMCIF_WAIT_FOR_STOP) {
		struct mmc_data *data = mrq->data;
		if (!mrq->cmd->error && data && !data->error)
			data->bytes_xfered =
				data->blocks * data->blksz;

		if (mrq->stop && !mrq->cmd->error && (!data || !data->error)) {
			sh_mmcif_stop_cmd(host, mrq);
			if (!mrq->stop->error) {
				schedule_delayed_work(&host->timeout_work, host->timeout);
				mutex_unlock(&host->thread_lock);
				return IRQ_HANDLED;
			}
		}
	}

	host->wait_for = MMCIF_WAIT_FOR_REQUEST;
	host->state = STATE_IDLE;
	host->mrq = NULL;
	mmc_request_done(host->mmc, mrq);

	mutex_unlock(&host->thread_lock);

	return IRQ_HANDLED;
}

static irqreturn_t sh_mmcif_intr(int irq, void *dev_id)
{
	struct sh_mmcif_host *host = dev_id;
	struct device *dev = sh_mmcif_host_to_dev(host);
	u32 state, mask;

	state = sh_mmcif_readl(host->addr, MMCIF_CE_INT);
	mask = sh_mmcif_readl(host->addr, MMCIF_CE_INT_MASK);
	if (host->ccs_enable)
		sh_mmcif_writel(host->addr, MMCIF_CE_INT, ~(state & mask));
	else
		sh_mmcif_writel(host->addr, MMCIF_CE_INT, INT_CCS | ~(state & mask));
	sh_mmcif_bitclr(host, MMCIF_CE_INT_MASK, state & MASK_CLEAN);

	if (state & ~MASK_CLEAN)
		dev_dbg(dev, "IRQ state = 0x%08x incompletely cleared\n",
			state);

	if (state & INT_ERR_STS || state & ~INT_ALL) {
		host->sd_error = true;
		dev_dbg(dev, "int err state = 0x%08x\n", state);
	}
	if (state & ~(INT_CMD12RBE | INT_CMD12CRE)) {
		if (!host->mrq)
			dev_dbg(dev, "NULL IRQ state = 0x%08x\n", state);
		if (!host->dma_active)
			return IRQ_WAKE_THREAD;
		else if (host->sd_error)
			sh_mmcif_dma_complete(host);
	} else {
		dev_dbg(dev, "Unexpected IRQ 0x%x\n", state);
	}

	return IRQ_HANDLED;
}

static void sh_mmcif_timeout_work(struct work_struct *work)
{
	struct delayed_work *d = to_delayed_work(work);
	struct sh_mmcif_host *host = container_of(d, struct sh_mmcif_host, timeout_work);
	struct mmc_request *mrq = host->mrq;
	struct device *dev = sh_mmcif_host_to_dev(host);
	unsigned long flags;

	if (host->dying)
		/* Don't run after mmc_remove_host() */
		return;

	spin_lock_irqsave(&host->lock, flags);
	if (host->state == STATE_IDLE) {
		spin_unlock_irqrestore(&host->lock, flags);
		return;
	}

	dev_err(dev, "Timeout waiting for %u on CMD%u\n",
		host->wait_for, mrq->cmd->opcode);

	host->state = STATE_TIMEOUT;
	spin_unlock_irqrestore(&host->lock, flags);

	/*
	 * Handle races with cancel_delayed_work(), unless
	 * cancel_delayed_work_sync() is used
	 */
	switch (host->wait_for) {
	case MMCIF_WAIT_FOR_CMD:
		mrq->cmd->error = sh_mmcif_error_manage(host);
		break;
	case MMCIF_WAIT_FOR_STOP:
		mrq->stop->error = sh_mmcif_error_manage(host);
		break;
	case MMCIF_WAIT_FOR_MREAD:
	case MMCIF_WAIT_FOR_MWRITE:
	case MMCIF_WAIT_FOR_READ:
	case MMCIF_WAIT_FOR_WRITE:
	case MMCIF_WAIT_FOR_READ_END:
	case MMCIF_WAIT_FOR_WRITE_END:
		mrq->data->error = sh_mmcif_error_manage(host);
		break;
	default:
		BUG();
	}

	host->state = STATE_IDLE;
	host->wait_for = MMCIF_WAIT_FOR_REQUEST;
	host->mrq = NULL;
	mmc_request_done(host->mmc, mrq);
}

static void sh_mmcif_init_ocr(struct sh_mmcif_host *host)
{
	struct device *dev = sh_mmcif_host_to_dev(host);
	struct sh_mmcif_plat_data *pd = dev->platform_data;
	struct mmc_host *mmc = host->mmc;

	mmc_regulator_get_supply(mmc);

	if (!pd)
		return;

	if (!mmc->ocr_avail)
		mmc->ocr_avail = pd->ocr;
	else if (pd->ocr)
		dev_warn(mmc_dev(mmc), "Platform OCR mask is ignored\n");
}

static int sh_mmcif_probe(struct platform_device *pdev)
{
	int ret = 0, irq[2];
	struct mmc_host *mmc;
	struct sh_mmcif_host *host;
	struct device *dev = &pdev->dev;
	struct sh_mmcif_plat_data *pd = dev->platform_data;
	void __iomem *reg;
	const char *name;

	irq[0] = platform_get_irq(pdev, 0);
	irq[1] = platform_get_irq_optional(pdev, 1);
	if (irq[0] < 0)
		return irq[0];

	reg = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(reg))
		return PTR_ERR(reg);

	mmc = mmc_alloc_host(sizeof(struct sh_mmcif_host), dev);
	if (!mmc)
		return -ENOMEM;

	ret = mmc_of_parse(mmc);
	if (ret < 0)
		goto err_host;

	host		= mmc_priv(mmc);
	host->mmc	= mmc;
	host->addr	= reg;
	host->timeout	= msecs_to_jiffies(10000);
	host->ccs_enable = true;
	host->clk_ctrl2_enable = false;

	host->pd = pdev;

	spin_lock_init(&host->lock);

	mmc->ops = &sh_mmcif_ops;
	sh_mmcif_init_ocr(host);

	mmc->caps |= MMC_CAP_MMC_HIGHSPEED | MMC_CAP_WAIT_WHILE_BUSY;
	mmc->caps2 |= MMC_CAP2_NO_SD | MMC_CAP2_NO_SDIO;
	mmc->max_busy_timeout = 10000;

	if (pd && pd->caps)
		mmc->caps |= pd->caps;
	mmc->max_segs = 32;
	mmc->max_blk_size = 512;
	mmc->max_req_size = PAGE_SIZE * mmc->max_segs;
	mmc->max_blk_count = mmc->max_req_size / mmc->max_blk_size;
	mmc->max_seg_size = mmc->max_req_size;

	platform_set_drvdata(pdev, host);

	host->clk = devm_clk_get(dev, NULL);
	if (IS_ERR(host->clk)) {
		ret = PTR_ERR(host->clk);
		dev_err(dev, "cannot get clock: %d\n", ret);
		goto err_host;
	}

	ret = clk_prepare_enable(host->clk);
	if (ret < 0)
		goto err_host;

	sh_mmcif_clk_setup(host);

	pm_runtime_enable(dev);
	host->power = false;

	ret = pm_runtime_get_sync(dev);
	if (ret < 0)
		goto err_clk;

	INIT_DELAYED_WORK(&host->timeout_work, sh_mmcif_timeout_work);

	sh_mmcif_sync_reset(host);
	sh_mmcif_writel(host->addr, MMCIF_CE_INT_MASK, MASK_ALL);

	name = irq[1] < 0 ? dev_name(dev) : "sh_mmc:error";
	ret = devm_request_threaded_irq(dev, irq[0], sh_mmcif_intr,
					sh_mmcif_irqt, 0, name, host);
	if (ret) {
		dev_err(dev, "request_irq error (%s)\n", name);
		goto err_clk;
	}
	if (irq[1] >= 0) {
		ret = devm_request_threaded_irq(dev, irq[1],
						sh_mmcif_intr, sh_mmcif_irqt,
						0, "sh_mmc:int", host);
		if (ret) {
			dev_err(dev, "request_irq error (sh_mmc:int)\n");
			goto err_clk;
		}
	}

	mutex_init(&host->thread_lock);

	ret = mmc_add_host(mmc);
	if (ret < 0)
		goto err_clk;

	dev_pm_qos_expose_latency_limit(dev, 100);

	dev_info(dev, "Chip version 0x%04x, clock rate %luMHz\n",
		 sh_mmcif_readl(host->addr, MMCIF_CE_VERSION) & 0xffff,
		 clk_get_rate(host->clk) / 1000000UL);

	pm_runtime_put(dev);
	clk_disable_unprepare(host->clk);
	return ret;

err_clk:
	clk_disable_unprepare(host->clk);
	pm_runtime_put_sync(dev);
	pm_runtime_disable(dev);
err_host:
	mmc_free_host(mmc);
	return ret;
}

static void sh_mmcif_remove(struct platform_device *pdev)
{
	struct sh_mmcif_host *host = platform_get_drvdata(pdev);

	host->dying = true;
	clk_prepare_enable(host->clk);
	pm_runtime_get_sync(&pdev->dev);

	dev_pm_qos_hide_latency_limit(&pdev->dev);

	mmc_remove_host(host->mmc);
	sh_mmcif_writel(host->addr, MMCIF_CE_INT_MASK, MASK_ALL);

	/*
	 * FIXME: cancel_delayed_work(_sync)() and free_irq() race with the
	 * mmc_remove_host() call above. But swapping order doesn't help either
	 * (a query on the linux-mmc mailing list didn't bring any replies).
	 */
	cancel_delayed_work_sync(&host->timeout_work);

	clk_disable_unprepare(host->clk);
	mmc_free_host(host->mmc);
	pm_runtime_put_sync(&pdev->dev);
	pm_runtime_disable(&pdev->dev);
}

#ifdef CONFIG_PM_SLEEP
static int sh_mmcif_suspend(struct device *dev)
{
	struct sh_mmcif_host *host = dev_get_drvdata(dev);

	pm_runtime_get_sync(dev);
	sh_mmcif_writel(host->addr, MMCIF_CE_INT_MASK, MASK_ALL);
	pm_runtime_put(dev);

	return 0;
}

static int sh_mmcif_resume(struct device *dev)
{
	return 0;
}
#endif

static const struct dev_pm_ops sh_mmcif_dev_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(sh_mmcif_suspend, sh_mmcif_resume)
};

static struct platform_driver sh_mmcif_driver = {
	.probe		= sh_mmcif_probe,
	.remove_new	= sh_mmcif_remove,
	.driver		= {
		.name	= DRIVER_NAME,
		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
		.pm	= &sh_mmcif_dev_pm_ops,
		.of_match_table = sh_mmcif_of_match,
	},
};

module_platform_driver(sh_mmcif_driver);

MODULE_DESCRIPTION("SuperH on-chip MMC/eMMC interface driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:" DRIVER_NAME);
MODULE_AUTHOR("Yusuke Goda <yusuke.goda.sx@renesas.com>");