drivers/mmc/mmc_spi.c - platform/external/u-boot - Gitiles

 /*
  * generic mmc spi driver
  *
  * Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw>
  * Copyright 2019 Bhargav Shah <bhargavshah1988@gmail.com>
  *
  * Licensed under the GPL-2 or later.
  */
 #include <common.h>
 #include <errno.h>
 #include <log.h>
 #include <malloc.h>
 #include <part.h>
 #include <mmc.h>
 #include <stdlib.h>
 #include <linux/bitops.h>
 #include <u-boot/crc.h>
 #include <linux/crc7.h>
 #include <asm/byteorder.h>
 #include <dm.h>
 #include <spi.h>

 /* MMC/SD in SPI mode reports R1 status always */
 #define R1_SPI_IDLE			BIT(0)
 #define R1_SPI_ERASE_RESET		BIT(1)
 #define R1_SPI_ILLEGAL_COMMAND		BIT(2)
 #define R1_SPI_COM_CRC			BIT(3)
 #define R1_SPI_ERASE_SEQ		BIT(4)
 #define R1_SPI_ADDRESS			BIT(5)
 #define R1_SPI_PARAMETER		BIT(6)
 /* R1 bit 7 is always zero, reuse this bit for error */
 #define R1_SPI_ERROR			BIT(7)

 /* Response tokens used to ack each block written: */
 #define SPI_MMC_RESPONSE_CODE(x)	((x) & 0x1f)
 #define SPI_RESPONSE_ACCEPTED		((2 << 1)|1)
 #define SPI_RESPONSE_CRC_ERR		((5 << 1)|1)
 #define SPI_RESPONSE_WRITE_ERR		((6 << 1)|1)

 /* Read and write blocks start with these tokens and end with crc;
  * on error, read tokens act like a subset of R2_SPI_* values.
  */
 /* single block write multiblock read */
 #define SPI_TOKEN_SINGLE		0xfe
 /* multiblock write */
 #define SPI_TOKEN_MULTI_WRITE		0xfc
 /* terminate multiblock write */
 #define SPI_TOKEN_STOP_TRAN		0xfd

 /* MMC SPI commands start with a start bit "0" and a transmit bit "1" */
 #define MMC_SPI_CMD(x) (0x40 | (x))

 /* bus capability */
 #define MMC_SPI_VOLTAGE			(MMC_VDD_32_33 | MMC_VDD_33_34)
 #define MMC_SPI_MIN_CLOCK		400000	/* 400KHz to meet MMC spec */
 #define MMC_SPI_MAX_CLOCK		25000000 /* SD/MMC legacy speed */

 /* timeout value */
 #define CMD_TIMEOUT			8
 #define READ_TIMEOUT			3000000 /* 1 sec */
 #define WRITE_TIMEOUT			3000000 /* 1 sec */
 #define R1B_TIMEOUT			3000000 /* 1 sec */

 struct mmc_spi_plat {
 	struct mmc_config cfg;
 	struct mmc mmc;
 };

 struct mmc_spi_priv {
 	struct spi_slave *spi;
 };

 static int mmc_spi_sendcmd(struct udevice *dev,
 			   ushort cmdidx, u32 cmdarg, u32 resp_type,
 			   u8 *resp, u32 resp_size,
 			   bool resp_match, u8 resp_match_value, bool r1b)
 {
 	int i, rpos = 0, ret = 0;
 	u8 cmdo[7], r;

 	debug("%s: cmd%d cmdarg=0x%x resp_type=0x%x "
 	      "resp_size=%d resp_match=%d resp_match_value=0x%x\n",
 	      __func__, cmdidx, cmdarg, resp_type,
 	      resp_size, resp_match, resp_match_value);

 	cmdo[0] = 0xff;
 	cmdo[1] = MMC_SPI_CMD(cmdidx);
 	cmdo[2] = cmdarg >> 24;
 	cmdo[3] = cmdarg >> 16;
 	cmdo[4] = cmdarg >> 8;
 	cmdo[5] = cmdarg;
 	cmdo[6] = (crc7(0, &cmdo[1], 5) << 1) | 0x01;
 	ret = dm_spi_xfer(dev, sizeof(cmdo) * 8, cmdo, NULL, SPI_XFER_BEGIN);
 	if (ret)
 		return ret;

 	ret = dm_spi_xfer(dev, 1 * 8, NULL, &r, 0);
 	if (ret)
 		return ret;

 	if (!resp || !resp_size)
 		return 0;

 	debug("%s: cmd%d", __func__, cmdidx);

 	if (resp_match) {
 		r = ~resp_match_value;
 		i = CMD_TIMEOUT;
 		while (i) {
 			ret = dm_spi_xfer(dev, 1 * 8, NULL, &r, 0);
 			if (ret)
 				return ret;
 			debug(" resp%d=0x%x", rpos, r);
 			rpos++;
 			i--;

 			if (r == resp_match_value)
 				break;
 		}
 		if (!i && (r != resp_match_value))
 			return -ETIMEDOUT;
 	}

 	for (i = 0; i < resp_size; i++) {
 		if (i == 0 && resp_match) {
 			resp[i] = resp_match_value;
 			continue;
 		}
 		ret = dm_spi_xfer(dev, 1 * 8, NULL, &r, 0);
 		if (ret)
 			return ret;
 		debug(" resp%d=0x%x", rpos, r);
 		rpos++;
 		resp[i] = r;
 	}

 	if (r1b == true) {
 		i = R1B_TIMEOUT;
 		while (i) {
 			ret = dm_spi_xfer(dev, 1 * 8, NULL, &r, 0);
 			if (ret)
 				return ret;

 			debug(" resp%d=0x%x", rpos, r);
 			rpos++;
 			i--;

 			if (r)
 				break;
 		}
 		if (!i)
 			return -ETIMEDOUT;
 	}

 	debug("\n");

 	return 0;
 }

 static int mmc_spi_readdata(struct udevice *dev,
 			    void *xbuf, u32 bcnt, u32 bsize)
 {
 	u16 crc;
 	u8 *buf = xbuf, r1;
 	int i, ret = 0;

 	while (bcnt--) {
 		for (i = 0; i < READ_TIMEOUT; i++) {
 			ret = dm_spi_xfer(dev, 1 * 8, NULL, &r1, 0);
 			if (ret)
 				return ret;
 			if (r1 == SPI_TOKEN_SINGLE)
 				break;
 		}
 		debug("%s: data tok%d 0x%x\n", __func__, i, r1);
 		if (r1 == SPI_TOKEN_SINGLE) {
 			ret = dm_spi_xfer(dev, bsize * 8, NULL, buf, 0);
 			if (ret)
 				return ret;
 			ret = dm_spi_xfer(dev, 2 * 8, NULL, &crc, 0);
 			if (ret)
 				return ret;
 #ifdef CONFIG_MMC_SPI_CRC_ON
 			if (be16_to_cpu(crc16_ccitt(0, buf, bsize)) != crc) {
 				debug("%s: data crc error\n", __func__);
 				r1 = R1_SPI_COM_CRC;
 				break;
 			}
 #endif
 			r1 = 0;
 		} else {
 			r1 = R1_SPI_ERROR;
 			break;
 		}
 		buf += bsize;
 	}

 	if (r1 & R1_SPI_COM_CRC)
 		ret = -ECOMM;
 	else if (r1) /* other errors */
 		ret = -ETIMEDOUT;

 	return ret;
 }

 static int mmc_spi_writedata(struct udevice *dev, const void *xbuf,
 			     u32 bcnt, u32 bsize, int multi)
 {
 	const u8 *buf = xbuf;
 	u8 r1, tok[2];
 	u16 crc;
 	int i, ret = 0;

 	tok[0] = 0xff;
 	tok[1] = multi ? SPI_TOKEN_MULTI_WRITE : SPI_TOKEN_SINGLE;

 	while (bcnt--) {
 #ifdef CONFIG_MMC_SPI_CRC_ON
 		crc = cpu_to_be16(crc16_ccitt(0, (u8 *)buf, bsize));
 #endif
 		dm_spi_xfer(dev, 2 * 8, tok, NULL, 0);
 		dm_spi_xfer(dev, bsize * 8, buf, NULL, 0);
 		dm_spi_xfer(dev, 2 * 8, &crc, NULL, 0);
 		for (i = 0; i < CMD_TIMEOUT; i++) {
 			dm_spi_xfer(dev, 1 * 8, NULL, &r1, 0);
 			if ((r1 & 0x10) == 0) /* response token */
 				break;
 		}
 		debug("%s: data tok%d 0x%x\n", __func__, i, r1);
 		if (SPI_MMC_RESPONSE_CODE(r1) == SPI_RESPONSE_ACCEPTED) {
 			debug("%s: data accepted\n", __func__);
 			for (i = 0; i < WRITE_TIMEOUT; i++) { /* wait busy */
 				dm_spi_xfer(dev, 1 * 8, NULL, &r1, 0);
 				if (i && r1 == 0xff) {
 					r1 = 0;
 					break;
 				}
 			}
 			if (i == WRITE_TIMEOUT) {
 				debug("%s: data write timeout 0x%x\n",
 				      __func__, r1);
 				r1 = R1_SPI_ERROR;
 				break;
 			}
 		} else {
 			debug("%s: data error 0x%x\n", __func__, r1);
 			r1 = R1_SPI_COM_CRC;
 			break;
 		}
 		buf += bsize;
 	}
 	if (multi && bcnt == -1) { /* stop multi write */
 		tok[1] = SPI_TOKEN_STOP_TRAN;
 		dm_spi_xfer(dev, 2 * 8, tok, NULL, 0);
 		for (i = 0; i < WRITE_TIMEOUT; i++) { /* wait busy */
 			dm_spi_xfer(dev, 1 * 8, NULL, &r1, 0);
 			if (i && r1 == 0xff) {
 				r1 = 0;
 				break;
 			}
 		}
 		if (i == WRITE_TIMEOUT) {
 			debug("%s: data write timeout 0x%x\n", __func__, r1);
 			r1 = R1_SPI_ERROR;
 		}
 	}

 	if (r1 & R1_SPI_COM_CRC)
 		ret = -ECOMM;
 	else if (r1) /* other errors */
 		ret = -ETIMEDOUT;

 	return ret;
 }

 static int dm_mmc_spi_set_ios(struct udevice *dev)
 {
 	return 0;
 }

 static int dm_mmc_spi_request(struct udevice *dev, struct mmc_cmd *cmd,
 			      struct mmc_data *data)
 {
 	int i, multi, ret = 0;
 	u8 *resp = NULL;
 	u32 resp_size = 0;
 	bool resp_match = false, r1b = false;
 	u8 resp8 = 0, resp16[2] = { 0 }, resp40[5] = { 0 }, resp_match_value = 0;

 	dm_spi_claim_bus(dev);

 	for (i = 0; i < 4; i++)
 		cmd->response[i] = 0;

 	switch (cmd->cmdidx) {
 	case SD_CMD_APP_SEND_OP_COND:
 	case MMC_CMD_SEND_OP_COND:
 		resp = &resp8;
 		resp_size = sizeof(resp8);
 		cmd->cmdarg = 0x40000000;
 		break;
 	case SD_CMD_SEND_IF_COND:
 		resp = (u8 *)&resp40[0];
 		resp_size = sizeof(resp40);
 		resp_match = true;
 		resp_match_value = R1_SPI_IDLE;
 		break;
 	case MMC_CMD_SPI_READ_OCR:
 		resp = (u8 *)&resp40[0];
 		resp_size = sizeof(resp40);
 		break;
 	case MMC_CMD_SEND_STATUS:
 		resp = (u8 *)&resp16[0];
 		resp_size = sizeof(resp16);
 		break;
 	case MMC_CMD_SET_BLOCKLEN:
 	case MMC_CMD_SPI_CRC_ON_OFF:
 		resp = &resp8;
 		resp_size = sizeof(resp8);
 		resp_match = true;
 		resp_match_value = 0x0;
 		break;
 	case MMC_CMD_STOP_TRANSMISSION:
 	case MMC_CMD_ERASE:
 		resp = &resp8;
 		resp_size = sizeof(resp8);
 		r1b = true;
 		break;
 	case MMC_CMD_SEND_CSD:
 	case MMC_CMD_SEND_CID:
 	case MMC_CMD_READ_SINGLE_BLOCK:
 	case MMC_CMD_READ_MULTIPLE_BLOCK:
 	case MMC_CMD_WRITE_SINGLE_BLOCK:
 	case MMC_CMD_WRITE_MULTIPLE_BLOCK:
 	case MMC_CMD_APP_CMD:
 	case SD_CMD_ERASE_WR_BLK_START:
 	case SD_CMD_ERASE_WR_BLK_END:
 		resp = &resp8;
 		resp_size = sizeof(resp8);
 		break;
 	default:
 		resp = &resp8;
 		resp_size = sizeof(resp8);
 		resp_match = true;
 		resp_match_value = R1_SPI_IDLE;
 		break;
 	};

 	ret = mmc_spi_sendcmd(dev, cmd->cmdidx, cmd->cmdarg, cmd->resp_type,
 			      resp, resp_size, resp_match, resp_match_value, r1b);
 	if (ret)
 		goto done;

 	switch (cmd->cmdidx) {
 	case SD_CMD_APP_SEND_OP_COND:
 	case MMC_CMD_SEND_OP_COND:
 		cmd->response[0] = (resp8 & R1_SPI_IDLE) ? 0 : OCR_BUSY;
 		break;
 	case SD_CMD_SEND_IF_COND:
 	case MMC_CMD_SPI_READ_OCR:
 		cmd->response[0] = resp40[4];
 		cmd->response[0] |= (uint)resp40[3] << 8;
 		cmd->response[0] |= (uint)resp40[2] << 16;
 		cmd->response[0] |= (uint)resp40[1] << 24;
 		break;
 	case MMC_CMD_SEND_STATUS:
 		if (resp16[0] || resp16[1])
 			cmd->response[0] = MMC_STATUS_ERROR;
 		else
 			cmd->response[0] = MMC_STATUS_RDY_FOR_DATA;
 		break;
 	case MMC_CMD_SEND_CID:
 	case MMC_CMD_SEND_CSD:
 		ret = mmc_spi_readdata(dev, cmd->response, 1, 16);
 		if (ret)
 			return ret;
 		for (i = 0; i < 4; i++)
 			cmd->response[i] =
 				cpu_to_be32(cmd->response[i]);
 		break;
 	default:
 		cmd->response[0] = resp8;
 		break;
 	}

 	debug("%s: cmd%d resp0=0x%x resp1=0x%x resp2=0x%x resp3=0x%x\n",
 	      __func__, cmd->cmdidx, cmd->response[0], cmd->response[1],
 	      cmd->response[2], cmd->response[3]);

 	if (data) {
 		debug("%s: data flags=0x%x blocks=%d block_size=%d\n",
 		      __func__, data->flags, data->blocks, data->blocksize);
 		multi = (cmd->cmdidx == MMC_CMD_WRITE_MULTIPLE_BLOCK);
 		if (data->flags == MMC_DATA_READ)
 			ret = mmc_spi_readdata(dev, data->dest,
 					       data->blocks, data->blocksize);
 		else if  (data->flags == MMC_DATA_WRITE)
 			ret = mmc_spi_writedata(dev, data->src,
 						data->blocks, data->blocksize,
 						multi);
 	}

 done:
 	dm_spi_xfer(dev, 0, NULL, NULL, SPI_XFER_END);

 	dm_spi_release_bus(dev);

 	return ret;
 }

 static int mmc_spi_probe(struct udevice *dev)
 {
 	struct mmc_spi_priv *priv = dev_get_priv(dev);
 	struct mmc_spi_plat *plat = dev_get_plat(dev);
 	struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
 	char *name;

 	priv->spi = dev_get_parent_priv(dev);
 	if (!priv->spi->max_hz)
 		priv->spi->max_hz = MMC_SPI_MAX_CLOCK;
 	priv->spi->mode = SPI_MODE_0;
 	priv->spi->wordlen = 8;

 	name = malloc(strlen(dev->parent->name) + strlen(dev->name) + 4);
 	if (!name)
 		return -ENOMEM;
 	sprintf(name, "%s:%s", dev->parent->name, dev->name);

 	plat->cfg.name = name;
 	plat->cfg.host_caps = MMC_MODE_SPI;
 	plat->cfg.voltages = MMC_SPI_VOLTAGE;
 	plat->cfg.f_min = MMC_SPI_MIN_CLOCK;
 	plat->cfg.f_max = priv->spi->max_hz;
 	plat->cfg.part_type = PART_TYPE_DOS;
 	plat->cfg.b_max = CONFIG_SYS_MMC_MAX_BLK_COUNT;

 	plat->mmc.cfg = &plat->cfg;
 	plat->mmc.priv = priv;
 	plat->mmc.dev = dev;

 	upriv->mmc = &plat->mmc;

 	return 0;
 }

 static int mmc_spi_bind(struct udevice *dev)
 {
 	struct mmc_spi_plat *plat = dev_get_plat(dev);

 	return mmc_bind(dev, &plat->mmc, &plat->cfg);
 }

 static const struct dm_mmc_ops mmc_spi_ops = {
 	.send_cmd	= dm_mmc_spi_request,
 	.set_ios	= dm_mmc_spi_set_ios,
 };

 static const struct udevice_id dm_mmc_spi_match[] = {
 	{ .compatible = "mmc-spi-slot" },
 	{ /* sentinel */ }
 };

 U_BOOT_DRIVER(mmc_spi) = {
 	.name = "mmc_spi",
 	.id = UCLASS_MMC,
 	.of_match = dm_mmc_spi_match,
 	.ops = &mmc_spi_ops,
 	.probe = mmc_spi_probe,
 	.bind = mmc_spi_bind,
 	.plat_auto	= sizeof(struct mmc_spi_plat),
 	.priv_auto	= sizeof(struct mmc_spi_priv),
 };
	/*
	* generic mmc spi driver
	*
	* Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw>
	* Copyright 2019 Bhargav Shah <bhargavshah1988@gmail.com>
	*
	* Licensed under the GPL-2 or later.
	*/
	#include <common.h>
	#include <errno.h>
	#include <log.h>
	#include <malloc.h>
	#include <part.h>
	#include <mmc.h>
	#include <stdlib.h>
	#include <linux/bitops.h>
	#include <u-boot/crc.h>
	#include <linux/crc7.h>
	#include <asm/byteorder.h>
	#include <dm.h>
	#include <spi.h>

	/* MMC/SD in SPI mode reports R1 status always */
	#define R1_SPI_IDLE BIT(0)
	#define R1_SPI_ERASE_RESET BIT(1)
	#define R1_SPI_ILLEGAL_COMMAND BIT(2)
	#define R1_SPI_COM_CRC BIT(3)
	#define R1_SPI_ERASE_SEQ BIT(4)
	#define R1_SPI_ADDRESS BIT(5)
	#define R1_SPI_PARAMETER BIT(6)
	/* R1 bit 7 is always zero, reuse this bit for error */
	#define R1_SPI_ERROR BIT(7)

	/* Response tokens used to ack each block written: */
	#define SPI_MMC_RESPONSE_CODE(x) ((x) & 0x1f)
	#define SPI_RESPONSE_ACCEPTED ((2 << 1)\|1)
	#define SPI_RESPONSE_CRC_ERR ((5 << 1)\|1)
	#define SPI_RESPONSE_WRITE_ERR ((6 << 1)\|1)

	/* Read and write blocks start with these tokens and end with crc;
	* on error, read tokens act like a subset of R2_SPI_* values.
	*/
	/* single block write multiblock read */
	#define SPI_TOKEN_SINGLE 0xfe
	/* multiblock write */
	#define SPI_TOKEN_MULTI_WRITE 0xfc
	/* terminate multiblock write */
	#define SPI_TOKEN_STOP_TRAN 0xfd

	/* MMC SPI commands start with a start bit "0" and a transmit bit "1" */
	#define MMC_SPI_CMD(x) (0x40 \| (x))

	/* bus capability */
	#define MMC_SPI_VOLTAGE (MMC_VDD_32_33 \| MMC_VDD_33_34)
	#define MMC_SPI_MIN_CLOCK 400000 /* 400KHz to meet MMC spec */
	#define MMC_SPI_MAX_CLOCK 25000000 /* SD/MMC legacy speed */

	/* timeout value */
	#define CMD_TIMEOUT 8
	#define READ_TIMEOUT 3000000 /* 1 sec */
	#define WRITE_TIMEOUT 3000000 /* 1 sec */
	#define R1B_TIMEOUT 3000000 /* 1 sec */

	struct mmc_spi_plat {
	struct mmc_config cfg;
	struct mmc mmc;
	};

	struct mmc_spi_priv {
	struct spi_slave *spi;
	};

	static int mmc_spi_sendcmd(struct udevice *dev,
	ushort cmdidx, u32 cmdarg, u32 resp_type,
	u8 *resp, u32 resp_size,
	bool resp_match, u8 resp_match_value, bool r1b)
	{
	int i, rpos = 0, ret = 0;
	u8 cmdo[7], r;

	debug("%s: cmd%d cmdarg=0x%x resp_type=0x%x "
	"resp_size=%d resp_match=%d resp_match_value=0x%x\n",
	__func__, cmdidx, cmdarg, resp_type,
	resp_size, resp_match, resp_match_value);

	cmdo[0] = 0xff;
	cmdo[1] = MMC_SPI_CMD(cmdidx);
	cmdo[2] = cmdarg >> 24;
	cmdo[3] = cmdarg >> 16;
	cmdo[4] = cmdarg >> 8;
	cmdo[5] = cmdarg;
	cmdo[6] = (crc7(0, &cmdo[1], 5) << 1) \| 0x01;
	ret = dm_spi_xfer(dev, sizeof(cmdo) * 8, cmdo, NULL, SPI_XFER_BEGIN);
	if (ret)
	return ret;

	ret = dm_spi_xfer(dev, 1 * 8, NULL, &r, 0);
	if (ret)
	return ret;

	if (!resp \|\| !resp_size)
	return 0;

	debug("%s: cmd%d", __func__, cmdidx);

	if (resp_match) {
	r = ~resp_match_value;
	i = CMD_TIMEOUT;
	while (i) {
	ret = dm_spi_xfer(dev, 1 * 8, NULL, &r, 0);
	if (ret)
	return ret;
	debug(" resp%d=0x%x", rpos, r);
	rpos++;
	i--;

	if (r == resp_match_value)
	break;
	}
	if (!i && (r != resp_match_value))
	return -ETIMEDOUT;
	}

	for (i = 0; i < resp_size; i++) {
	if (i == 0 && resp_match) {
	resp[i] = resp_match_value;
	continue;
	}
	ret = dm_spi_xfer(dev, 1 * 8, NULL, &r, 0);
	if (ret)
	return ret;
	debug(" resp%d=0x%x", rpos, r);
	rpos++;
	resp[i] = r;
	}

	if (r1b == true) {
	i = R1B_TIMEOUT;
	while (i) {
	ret = dm_spi_xfer(dev, 1 * 8, NULL, &r, 0);
	if (ret)
	return ret;

	debug(" resp%d=0x%x", rpos, r);
	rpos++;
	i--;

	if (r)
	break;
	}
	if (!i)
	return -ETIMEDOUT;
	}

	debug("\n");

	return 0;
	}

	static int mmc_spi_readdata(struct udevice *dev,
	void *xbuf, u32 bcnt, u32 bsize)
	{
	u16 crc;
	u8 *buf = xbuf, r1;
	int i, ret = 0;

	while (bcnt--) {
	for (i = 0; i < READ_TIMEOUT; i++) {
	ret = dm_spi_xfer(dev, 1 * 8, NULL, &r1, 0);
	if (ret)
	return ret;
	if (r1 == SPI_TOKEN_SINGLE)
	break;
	}
	debug("%s: data tok%d 0x%x\n", __func__, i, r1);
	if (r1 == SPI_TOKEN_SINGLE) {
	ret = dm_spi_xfer(dev, bsize * 8, NULL, buf, 0);
	if (ret)
	return ret;
	ret = dm_spi_xfer(dev, 2 * 8, NULL, &crc, 0);
	if (ret)
	return ret;
	#ifdef CONFIG_MMC_SPI_CRC_ON
	if (be16_to_cpu(crc16_ccitt(0, buf, bsize)) != crc) {
	debug("%s: data crc error\n", __func__);
	r1 = R1_SPI_COM_CRC;
	break;
	}
	#endif
	r1 = 0;
	} else {
	r1 = R1_SPI_ERROR;
	break;
	}
	buf += bsize;
	}

	if (r1 & R1_SPI_COM_CRC)
	ret = -ECOMM;
	else if (r1) /* other errors */
	ret = -ETIMEDOUT;

	return ret;
	}

	static int mmc_spi_writedata(struct udevice dev, const void xbuf,
	u32 bcnt, u32 bsize, int multi)
	{
	const u8 *buf = xbuf;
	u8 r1, tok[2];
	u16 crc;
	int i, ret = 0;

	tok[0] = 0xff;
	tok[1] = multi ? SPI_TOKEN_MULTI_WRITE : SPI_TOKEN_SINGLE;

	while (bcnt--) {
	#ifdef CONFIG_MMC_SPI_CRC_ON
	crc = cpu_to_be16(crc16_ccitt(0, (u8 *)buf, bsize));
	#endif
	dm_spi_xfer(dev, 2 * 8, tok, NULL, 0);
	dm_spi_xfer(dev, bsize * 8, buf, NULL, 0);
	dm_spi_xfer(dev, 2 * 8, &crc, NULL, 0);
	for (i = 0; i < CMD_TIMEOUT; i++) {
	dm_spi_xfer(dev, 1 * 8, NULL, &r1, 0);
	if ((r1 & 0x10) == 0) /* response token */
	break;
	}
	debug("%s: data tok%d 0x%x\n", __func__, i, r1);
	if (SPI_MMC_RESPONSE_CODE(r1) == SPI_RESPONSE_ACCEPTED) {
	debug("%s: data accepted\n", __func__);
	for (i = 0; i < WRITE_TIMEOUT; i++) { /* wait busy */
	dm_spi_xfer(dev, 1 * 8, NULL, &r1, 0);
	if (i && r1 == 0xff) {
	r1 = 0;
	break;
	}
	}
	if (i == WRITE_TIMEOUT) {
	debug("%s: data write timeout 0x%x\n",
	__func__, r1);
	r1 = R1_SPI_ERROR;
	break;
	}
	} else {
	debug("%s: data error 0x%x\n", __func__, r1);
	r1 = R1_SPI_COM_CRC;
	break;
	}
	buf += bsize;
	}
	if (multi && bcnt == -1) { /* stop multi write */
	tok[1] = SPI_TOKEN_STOP_TRAN;
	dm_spi_xfer(dev, 2 * 8, tok, NULL, 0);
	for (i = 0; i < WRITE_TIMEOUT; i++) { /* wait busy */
	dm_spi_xfer(dev, 1 * 8, NULL, &r1, 0);
	if (i && r1 == 0xff) {
	r1 = 0;
	break;
	}
	}
	if (i == WRITE_TIMEOUT) {
	debug("%s: data write timeout 0x%x\n", __func__, r1);
	r1 = R1_SPI_ERROR;
	}
	}

	if (r1 & R1_SPI_COM_CRC)
	ret = -ECOMM;
	else if (r1) /* other errors */
	ret = -ETIMEDOUT;

	return ret;
	}

	static int dm_mmc_spi_set_ios(struct udevice *dev)
	{
	return 0;
	}

	static int dm_mmc_spi_request(struct udevice dev, struct mmc_cmd cmd,
	struct mmc_data *data)
	{
	int i, multi, ret = 0;
	u8 *resp = NULL;
	u32 resp_size = 0;
	bool resp_match = false, r1b = false;
	u8 resp8 = 0, resp16[2] = { 0 }, resp40[5] = { 0 }, resp_match_value = 0;

	dm_spi_claim_bus(dev);

	for (i = 0; i < 4; i++)
	cmd->response[i] = 0;

	switch (cmd->cmdidx) {
	case SD_CMD_APP_SEND_OP_COND:
	case MMC_CMD_SEND_OP_COND:
	resp = &resp8;
	resp_size = sizeof(resp8);
	cmd->cmdarg = 0x40000000;
	break;
	case SD_CMD_SEND_IF_COND:
	resp = (u8 *)&resp40[0];
	resp_size = sizeof(resp40);
	resp_match = true;
	resp_match_value = R1_SPI_IDLE;
	break;
	case MMC_CMD_SPI_READ_OCR:
	resp = (u8 *)&resp40[0];
	resp_size = sizeof(resp40);
	break;
	case MMC_CMD_SEND_STATUS:
	resp = (u8 *)&resp16[0];
	resp_size = sizeof(resp16);
	break;
	case MMC_CMD_SET_BLOCKLEN:
	case MMC_CMD_SPI_CRC_ON_OFF:
	resp = &resp8;
	resp_size = sizeof(resp8);
	resp_match = true;
	resp_match_value = 0x0;
	break;
	case MMC_CMD_STOP_TRANSMISSION:
	case MMC_CMD_ERASE:
	resp = &resp8;
	resp_size = sizeof(resp8);
	r1b = true;
	break;
	case MMC_CMD_SEND_CSD:
	case MMC_CMD_SEND_CID:
	case MMC_CMD_READ_SINGLE_BLOCK:
	case MMC_CMD_READ_MULTIPLE_BLOCK:
	case MMC_CMD_WRITE_SINGLE_BLOCK:
	case MMC_CMD_WRITE_MULTIPLE_BLOCK:
	case MMC_CMD_APP_CMD:
	case SD_CMD_ERASE_WR_BLK_START:
	case SD_CMD_ERASE_WR_BLK_END:
	resp = &resp8;
	resp_size = sizeof(resp8);
	break;
	default:
	resp = &resp8;
	resp_size = sizeof(resp8);
	resp_match = true;
	resp_match_value = R1_SPI_IDLE;
	break;
	};

	ret = mmc_spi_sendcmd(dev, cmd->cmdidx, cmd->cmdarg, cmd->resp_type,
	resp, resp_size, resp_match, resp_match_value, r1b);
	if (ret)
	goto done;

	switch (cmd->cmdidx) {
	case SD_CMD_APP_SEND_OP_COND:
	case MMC_CMD_SEND_OP_COND:
	cmd->response[0] = (resp8 & R1_SPI_IDLE) ? 0 : OCR_BUSY;
	break;
	case SD_CMD_SEND_IF_COND:
	case MMC_CMD_SPI_READ_OCR:
	cmd->response[0] = resp40[4];
	cmd->response[0] \|= (uint)resp40[3] << 8;
	cmd->response[0] \|= (uint)resp40[2] << 16;
	cmd->response[0] \|= (uint)resp40[1] << 24;
	break;
	case MMC_CMD_SEND_STATUS:
	if (resp16[0] \|\| resp16[1])
	cmd->response[0] = MMC_STATUS_ERROR;
	else
	cmd->response[0] = MMC_STATUS_RDY_FOR_DATA;
	break;
	case MMC_CMD_SEND_CID:
	case MMC_CMD_SEND_CSD:
	ret = mmc_spi_readdata(dev, cmd->response, 1, 16);
	if (ret)
	return ret;
	for (i = 0; i < 4; i++)
	cmd->response[i] =
	cpu_to_be32(cmd->response[i]);
	break;
	default:
	cmd->response[0] = resp8;
	break;
	}

	debug("%s: cmd%d resp0=0x%x resp1=0x%x resp2=0x%x resp3=0x%x\n",
	__func__, cmd->cmdidx, cmd->response[0], cmd->response[1],
	cmd->response[2], cmd->response[3]);

	if (data) {
	debug("%s: data flags=0x%x blocks=%d block_size=%d\n",
	__func__, data->flags, data->blocks, data->blocksize);
	multi = (cmd->cmdidx == MMC_CMD_WRITE_MULTIPLE_BLOCK);
	if (data->flags == MMC_DATA_READ)
	ret = mmc_spi_readdata(dev, data->dest,
	data->blocks, data->blocksize);
	else if (data->flags == MMC_DATA_WRITE)
	ret = mmc_spi_writedata(dev, data->src,
	data->blocks, data->blocksize,
	multi);
	}

	done:
	dm_spi_xfer(dev, 0, NULL, NULL, SPI_XFER_END);

	dm_spi_release_bus(dev);

	return ret;
	}

	static int mmc_spi_probe(struct udevice *dev)
	{
	struct mmc_spi_priv *priv = dev_get_priv(dev);
	struct mmc_spi_plat *plat = dev_get_plat(dev);
	struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
	char *name;

	priv->spi = dev_get_parent_priv(dev);
	if (!priv->spi->max_hz)
	priv->spi->max_hz = MMC_SPI_MAX_CLOCK;
	priv->spi->mode = SPI_MODE_0;
	priv->spi->wordlen = 8;

	name = malloc(strlen(dev->parent->name) + strlen(dev->name) + 4);
	if (!name)
	return -ENOMEM;
	sprintf(name, "%s:%s", dev->parent->name, dev->name);

	plat->cfg.name = name;
	plat->cfg.host_caps = MMC_MODE_SPI;
	plat->cfg.voltages = MMC_SPI_VOLTAGE;
	plat->cfg.f_min = MMC_SPI_MIN_CLOCK;
	plat->cfg.f_max = priv->spi->max_hz;
	plat->cfg.part_type = PART_TYPE_DOS;
	plat->cfg.b_max = CONFIG_SYS_MMC_MAX_BLK_COUNT;

	plat->mmc.cfg = &plat->cfg;
	plat->mmc.priv = priv;
	plat->mmc.dev = dev;

	upriv->mmc = &plat->mmc;

	return 0;
	}

	static int mmc_spi_bind(struct udevice *dev)
	{
	struct mmc_spi_plat *plat = dev_get_plat(dev);

	return mmc_bind(dev, &plat->mmc, &plat->cfg);
	}

	static const struct dm_mmc_ops mmc_spi_ops = {
	.send_cmd = dm_mmc_spi_request,
	.set_ios = dm_mmc_spi_set_ios,
	};

	static const struct udevice_id dm_mmc_spi_match[] = {
	{ .compatible = "mmc-spi-slot" },
	{ /* sentinel */ }
	};

	U_BOOT_DRIVER(mmc_spi) = {
	.name = "mmc_spi",
	.id = UCLASS_MMC,
	.of_match = dm_mmc_spi_match,
	.ops = &mmc_spi_ops,
	.probe = mmc_spi_probe,
	.bind = mmc_spi_bind,
	.plat_auto = sizeof(struct mmc_spi_plat),
	.priv_auto = sizeof(struct mmc_spi_priv),
	};