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Message-ID: <2b3f8b30-1ee1-31dd-53d7-cb2a0deea511@intel.com>
Date:   Thu, 31 Aug 2023 11:33:17 +0300
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Subject: Re: [PATCH V10 18/23] mmc: sdhci-uhs2: add request() and others
Content-Language: en-US
To:     Victor Shih <victorshihgli@gmail.com>, ulf.hansson@linaro.org
Cc:     linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org,
        benchuanggli@gmail.com, HL.Liu@genesyslogic.com.tw,
        Greg.tu@genesyslogic.com.tw, takahiro.akashi@linaro.org,
        dlunev@chromium.org, Ben Chuang <ben.chuang@genesyslogic.com.tw>,
        Victor Shih <victor.shih@genesyslogic.com.tw>
References: <20230818100217.12725-1-victorshihgli@gmail.com>
 <20230818100217.12725-19-victorshihgli@gmail.com>
From:   Adrian Hunter <adrian.hunter@intel.com>
Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki,
 Business Identity Code: 0357606 - 4, Domiciled in Helsinki
In-Reply-To: <20230818100217.12725-19-victorshihgli@gmail.com>
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Precedence: bulk

On 18/08/23 13:02, Victor Shih wrote:
> From: Victor Shih <victor.shih@genesyslogic.com.tw>
> 
> This is a sdhci version of mmc's request operation.
> It covers both UHS-I and UHS-II.
> 
> Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> Signed-off-by: Victor Shih <victor.shih@genesyslogic.com.tw>
> ---
> 
> Updates in V10:
>  - Use tmode_half_duplex to instead of uhs2_tmode0_flag
>    in sdhci_uhs2_set_transfer_mode().
> 
> Updates in V9:
>  - Modify the annotations in __sdhci_uhs2_send_command().
> 
> Updates in V8:
>  - Adjust the position of matching brackets in
>    sdhci_uhs2_send_command_retry().
>  - Modify CameCase definition in __sdhci_uhs2_finish_command().
>  - Modify error message in __sdhci_uhs2_finish_command().
>  - sdhci_uhs2_send_command_retry() to instead of sdhci_uhs2_send_command()
>    in sdhci_uhs2_request().
>  - Use sdhci_uhs2_mode() to simplify code in sdhci_uhs2_request_atomic().
>  - Add forward declaration for sdhci_send_command().
> 
> Updates in V7:
>  - Cancel export state of some functions.
>  - Remove unnecessary whitespace changes.
> 
> Updates in V6:
>  - Add uhs2_dev_cmd() to simplify code.
>  - Remove unnecessary functions.
>  - Cancel export state of some functions.
>  - Drop use CONFIG_MMC_DEBUG().
>  - Wrap at 100 columns in some functions.
> 
> ---
> 
>  drivers/mmc/host/sdhci-uhs2.c | 412 ++++++++++++++++++++++++++++++++++
>  drivers/mmc/host/sdhci.c      |  49 ++--
>  drivers/mmc/host/sdhci.h      |   8 +
>  3 files changed, 454 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
> index 09b86fec9f7b..08fef7174239 100644
> --- a/drivers/mmc/host/sdhci-uhs2.c
> +++ b/drivers/mmc/host/sdhci-uhs2.c
> @@ -14,6 +14,8 @@
>  #include <linux/module.h>
>  #include <linux/iopoll.h>
>  #include <linux/bitfield.h>
> +#include <linux/mmc/mmc.h>
> +#include <linux/mmc/host.h>
>  
>  #include "sdhci.h"
>  #include "sdhci-uhs2.h"
> @@ -24,6 +26,8 @@
>  #define SDHCI_UHS2_DUMP(f, x...) \
>  	pr_err("%s: " DRIVER_NAME ": " f, mmc_hostname(host->mmc), ## x)
>  
> +#define UHS2_ARG_IOADR_MASK 0xfff
> +
>  void sdhci_uhs2_dump_regs(struct sdhci_host *host)
>  {
>  	if (!(sdhci_uhs2_mode(host)))
> @@ -58,6 +62,11 @@ EXPORT_SYMBOL_GPL(sdhci_uhs2_dump_regs);
>   *                                                                           *
>  \*****************************************************************************/
>  
> +static inline u16 uhs2_dev_cmd(struct mmc_command *cmd)
> +{
> +	return be16_to_cpu((__be16)cmd->uhs2_cmd->arg) & UHS2_ARG_IOADR_MASK;
> +}
> +
>  static inline int mmc_opt_regulator_set_ocr(struct mmc_host *mmc,
>  					    struct regulator *supply,
>  					    unsigned short vdd_bit)
> @@ -446,6 +455,408 @@ static int sdhci_uhs2_control(struct mmc_host *mmc, enum sd_uhs2_operation op)
>  	return err;
>  }
>  
> +/*****************************************************************************\
> + *                                                                           *
> + * Core functions                                                            *
> + *                                                                           *
> +\*****************************************************************************/
> +
> +static void sdhci_uhs2_prepare_data(struct sdhci_host *host, struct mmc_command *cmd)
> +{
> +	struct mmc_data *data = cmd->data;
> +
> +	sdhci_initialize_data(host, data);
> +
> +	sdhci_prepare_dma(host, data);
> +
> +	sdhci_writew(host, data->blksz, SDHCI_UHS2_BLOCK_SIZE);
> +	sdhci_writew(host, data->blocks, SDHCI_UHS2_BLOCK_COUNT);
> +}
> +
> +static void sdhci_uhs2_finish_data(struct sdhci_host *host)
> +{
> +	struct mmc_data *data = host->data;
> +
> +	__sdhci_finish_data_common(host);
> +
> +	__sdhci_finish_mrq(host, data->mrq);
> +}
> +
> +static void sdhci_uhs2_set_transfer_mode(struct sdhci_host *host, struct mmc_command *cmd)
> +{
> +	u16 mode;
> +	struct mmc_data *data = cmd->data;
> +
> +	if (!data) {
> +		/* clear Auto CMD settings for no data CMDs */
> +		if (uhs2_dev_cmd(cmd) == UHS2_DEV_CMD_TRANS_ABORT) {
> +			mode =  0;
> +		} else {
> +			mode = sdhci_readw(host, SDHCI_UHS2_TRANS_MODE);
> +			if (cmd->opcode == MMC_STOP_TRANSMISSION || cmd->opcode == MMC_ERASE)
> +				mode |= SDHCI_UHS2_TRNS_WAIT_EBSY;
> +			else
> +				/* send status mode */
> +				if (cmd->opcode == MMC_SEND_STATUS)
> +					mode = 0;
> +		}
> +
> +		DBG("UHS2 no data trans mode is 0x%x.\n", mode);
> +
> +		sdhci_writew(host, mode, SDHCI_UHS2_TRANS_MODE);
> +		return;
> +	}
> +
> +	WARN_ON(!host->data);
> +
> +	mode = SDHCI_UHS2_TRNS_BLK_CNT_EN | SDHCI_UHS2_TRNS_WAIT_EBSY;
> +	if (data->flags & MMC_DATA_WRITE)
> +		mode |= SDHCI_UHS2_TRNS_DATA_TRNS_WRT;
> +
> +	if (data->blocks == 1 &&
> +	    data->blksz != 512 &&
> +	    cmd->opcode != MMC_READ_SINGLE_BLOCK &&
> +	    cmd->opcode != MMC_WRITE_BLOCK) {
> +		mode &= ~SDHCI_UHS2_TRNS_BLK_CNT_EN;
> +		mode |= SDHCI_UHS2_TRNS_BLK_BYTE_MODE;
> +	}
> +
> +	if (host->flags & SDHCI_REQ_USE_DMA)
> +		mode |= SDHCI_UHS2_TRNS_DMA;
> +
> +	if ((mmc_card_uhs2_hd_mode(host->mmc)) && cmd->uhs2_cmd->tmode_half_duplex)

Should not check mmc_card_uhs2_hd_mode(host->mmc).  The mmc core
must get it right.

Also why is the setting different for different commands?

> +		mode |= SDHCI_UHS2_TRNS_2L_HD;
> +
> +	sdhci_writew(host, mode, SDHCI_UHS2_TRANS_MODE);
> +
> +	DBG("UHS2 trans mode is 0x%x.\n", mode);
> +}
> +
> +static void __sdhci_uhs2_send_command(struct sdhci_host *host, struct mmc_command *cmd)
> +{
> +	int i, j;
> +	int cmd_reg;
> +
> +	i = 0;
> +	sdhci_writel(host,
> +		     ((u32)cmd->uhs2_cmd->arg << 16) |
> +				(u32)cmd->uhs2_cmd->header,
> +		     SDHCI_UHS2_CMD_PACKET + i);
> +	i += 4;
> +
> +	/*
> +	 * Per spec, payload (config) should be MSB before sending out.
> +	 * But we don't need convert here because had set payload as
> +	 * MSB when preparing config read/write commands.
> +	 */
> +	for (j = 0; j < cmd->uhs2_cmd->payload_len / sizeof(u32); j++) {
> +		sdhci_writel(host, *(cmd->uhs2_cmd->payload + j), SDHCI_UHS2_CMD_PACKET + i);
> +		i += 4;
> +	}
> +
> +	for ( ; i < SDHCI_UHS2_CMD_PACK_MAX_LEN; i += 4)
> +		sdhci_writel(host, 0, SDHCI_UHS2_CMD_PACKET + i);
> +
> +	DBG("UHS2 CMD packet_len = %d.\n", cmd->uhs2_cmd->packet_len);
> +	for (i = 0; i < cmd->uhs2_cmd->packet_len; i++)
> +		DBG("UHS2 CMD_PACKET[%d] = 0x%x.\n", i,
> +		    sdhci_readb(host, SDHCI_UHS2_CMD_PACKET + i));
> +
> +	cmd_reg = FIELD_PREP(SDHCI_UHS2_CMD_PACK_LEN_MASK, cmd->uhs2_cmd->packet_len);
> +	if ((cmd->flags & MMC_CMD_MASK) == MMC_CMD_ADTC)
> +		cmd_reg |= SDHCI_UHS2_CMD_DATA;
> +	if (cmd->opcode == MMC_STOP_TRANSMISSION)
> +		cmd_reg |= SDHCI_UHS2_CMD_CMD12;
> +
> +	/* UHS2 Native ABORT */
> +	if ((cmd->uhs2_cmd->header & UHS2_NATIVE_PACKET) &&
> +	    (uhs2_dev_cmd(cmd) == UHS2_DEV_CMD_TRANS_ABORT))
> +		cmd_reg |= SDHCI_UHS2_CMD_TRNS_ABORT;
> +
> +	/* UHS2 Native DORMANT */
> +	if ((cmd->uhs2_cmd->header & UHS2_NATIVE_PACKET) &&
> +	    (uhs2_dev_cmd(cmd) == UHS2_DEV_CMD_GO_DORMANT_STATE))
> +		cmd_reg |= SDHCI_UHS2_CMD_DORMANT;
> +
> +	DBG("0x%x is set to UHS2 CMD register.\n", cmd_reg);
> +
> +	sdhci_writew(host, cmd_reg, SDHCI_UHS2_CMD);
> +}
> +
> +static bool sdhci_uhs2_send_command(struct sdhci_host *host, struct mmc_command *cmd)
> +{
> +	int flags;
> +	u32 mask;
> +	unsigned long timeout;
> +
> +	WARN_ON(host->cmd);
> +
> +	/* Initially, a command has no error */
> +	cmd->error = 0;
> +
> +	if (cmd->opcode == MMC_STOP_TRANSMISSION)
> +		cmd->flags |= MMC_RSP_BUSY;
> +
> +	mask = SDHCI_CMD_INHIBIT;
> +
> +	if (sdhci_readl(host, SDHCI_PRESENT_STATE) & mask)
> +		return false;
> +
> +	host->cmd = cmd;
> +	host->data_timeout = 0;
> +	if (sdhci_data_line_cmd(cmd)) {
> +		WARN_ON(host->data_cmd);
> +		host->data_cmd = cmd;
> +		__sdhci_uhs2_set_timeout(host);
> +	}
> +
> +	if (cmd->data)
> +		sdhci_uhs2_prepare_data(host, cmd);
> +
> +	sdhci_uhs2_set_transfer_mode(host, cmd);
> +
> +	if ((cmd->flags & MMC_RSP_136) && (cmd->flags & MMC_RSP_BUSY)) {
> +		WARN_ONCE(1, "Unsupported response type!\n");
> +		/*
> +		 * This does not happen in practice because 136-bit response
> +		 * commands never have busy waiting, so rather than complicate
> +		 * the error path, just remove busy waiting and continue.
> +		 */
> +		cmd->flags &= ~MMC_RSP_BUSY;
> +	}
> +
> +	if (!(cmd->flags & MMC_RSP_PRESENT))
> +		flags = SDHCI_CMD_RESP_NONE;
> +	else if (cmd->flags & MMC_RSP_136)
> +		flags = SDHCI_CMD_RESP_LONG;
> +	else if (cmd->flags & MMC_RSP_BUSY)
> +		flags = SDHCI_CMD_RESP_SHORT_BUSY;
> +	else
> +		flags = SDHCI_CMD_RESP_SHORT;
> +
> +	if (cmd->flags & MMC_RSP_CRC)
> +		flags |= SDHCI_CMD_CRC;
> +	if (cmd->flags & MMC_RSP_OPCODE)
> +		flags |= SDHCI_CMD_INDEX;
> +
> +	timeout = jiffies;
> +	if (host->data_timeout)
> +		timeout += nsecs_to_jiffies(host->data_timeout);
> +	else if (!cmd->data && cmd->busy_timeout > 9000)
> +		timeout += DIV_ROUND_UP(cmd->busy_timeout, 1000) * HZ + HZ;
> +	else
> +		timeout += 10 * HZ;
> +	sdhci_mod_timer(host, cmd->mrq, timeout);
> +
> +	__sdhci_uhs2_send_command(host, cmd);
> +
> +	return true;
> +}
> +
> +static bool sdhci_uhs2_send_command_retry(struct sdhci_host *host,
> +					  struct mmc_command *cmd,
> +					  unsigned long flags)
> +	__releases(host->lock)
> +	__acquires(host->lock)
> +{
> +	struct mmc_command *deferred_cmd = host->deferred_cmd;
> +	int timeout = 10; /* Approx. 10 ms */
> +	bool present;
> +
> +	while (!sdhci_uhs2_send_command(host, cmd)) {
> +		if (!timeout--) {
> +			pr_err("%s: Controller never released inhibit bit(s).\n",
> +			       mmc_hostname(host->mmc));
> +			sdhci_dumpregs(host);
> +			cmd->error = -EIO;
> +			return false;
> +		}
> +
> +		spin_unlock_irqrestore(&host->lock, flags);
> +
> +		usleep_range(1000, 1250);
> +
> +		present = host->mmc->ops->get_cd(host->mmc);
> +
> +		spin_lock_irqsave(&host->lock, flags);
> +
> +		/* A deferred command might disappear, handle that */
> +		if (cmd == deferred_cmd && cmd != host->deferred_cmd)
> +			return true;
> +
> +		if (sdhci_present_error(host, cmd, present))
> +			return false;
> +	}
> +
> +	if (cmd == host->deferred_cmd)
> +		host->deferred_cmd = NULL;
> +
> +	return true;
> +}
> +
> +static void __sdhci_uhs2_finish_command(struct sdhci_host *host)
> +{
> +	struct mmc_command *cmd = host->cmd;
> +	u8 resp;
> +	u8 ecode;
> +	bool breada0 = 0;
> +	int i;
> +
> +	if (host->mmc->flags & MMC_UHS2_SD_TRAN) {
> +		resp = sdhci_readb(host, SDHCI_UHS2_RESPONSE + 2);
> +		if (resp & UHS2_RES_NACK_MASK) {
> +			ecode = (resp >> UHS2_RES_ECODE_POS) & UHS2_RES_ECODE_MASK;
> +			pr_err("%s: NACK response, ECODE=0x%x.\n", mmc_hostname(host->mmc), ecode);
> +		}
> +		breada0 = 1;
> +	}
> +
> +	if (cmd->uhs2_resp &&
> +	    cmd->uhs2_resp_len && cmd->uhs2_resp_len <= 20) {
> +		/* Get whole response of some native CCMD, like
> +		 * DEVICE_INIT, ENUMERATE.
> +		 */
> +		for (i = 0; i < cmd->uhs2_resp_len; i++)
> +			cmd->uhs2_resp[i] = sdhci_readb(host, SDHCI_UHS2_RESPONSE + i);
> +	} else {
> +		/* Get SD CMD response and Payload for some read
> +		 * CCMD, like INQUIRY_CFG.
> +		 */
> +		/* Per spec (p136), payload field is divided into
> +		 * a unit of DWORD and transmission order within
> +		 * a DWORD is big endian.
> +		 */
> +		if (!breada0)
> +			sdhci_readl(host, SDHCI_UHS2_RESPONSE);
> +		for (i = 4; i < 20; i += 4) {
> +			cmd->resp[i / 4 - 1] =
> +				(sdhci_readb(host,
> +					     SDHCI_UHS2_RESPONSE + i) << 24) |
> +				(sdhci_readb(host,
> +					     SDHCI_UHS2_RESPONSE + i + 1)
> +					<< 16) |
> +				(sdhci_readb(host,
> +					     SDHCI_UHS2_RESPONSE + i + 2)
> +					<< 8) |
> +				sdhci_readb(host, SDHCI_UHS2_RESPONSE + i + 3);
> +		}
> +	}
> +}
> +
> +static void sdhci_uhs2_finish_command(struct sdhci_host *host)
> +{
> +	struct mmc_command *cmd = host->cmd;
> +
> +	__sdhci_uhs2_finish_command(host);
> +
> +	host->cmd = NULL;
> +
> +	if (cmd->mrq->cap_cmd_during_tfr && cmd == cmd->mrq->cmd)
> +		mmc_command_done(host->mmc, cmd->mrq);
> +
> +	/*
> +	 * The host can send and interrupt when the busy state has
> +	 * ended, allowing us to wait without wasting CPU cycles.
> +	 * The busy signal uses DAT0 so this is similar to waiting
> +	 * for data to complete.
> +	 *
> +	 * Note: The 1.0 specification is a bit ambiguous about this
> +	 *       feature so there might be some problems with older
> +	 *       controllers.
> +	 */
> +	if (cmd->flags & MMC_RSP_BUSY) {
> +		if (cmd->data) {
> +			DBG("Cannot wait for busy signal when also doing a data transfer");
> +		} else if (!(host->quirks & SDHCI_QUIRK_NO_BUSY_IRQ) &&
> +			   cmd == host->data_cmd) {
> +			/* Command complete before busy is ended */
> +			return;
> +		}
> +	}
> +
> +	/* Processed actual command. */
> +	if (host->data && host->data_early)
> +		sdhci_uhs2_finish_data(host);
> +
> +	if (!cmd->data)
> +		__sdhci_finish_mrq(host, cmd->mrq);
> +}
> +
> +void sdhci_uhs2_request(struct mmc_host *mmc, struct mmc_request *mrq)
> +{
> +	struct sdhci_host *host = mmc_priv(mmc);
> +	struct mmc_command *cmd;
> +	unsigned long flags;
> +	bool present;
> +
> +	if (!(sdhci_uhs2_mode(host))) {
> +		sdhci_request(mmc, mrq);
> +		return;
> +	}
> +
> +	mrq->stop = NULL;
> +	mrq->sbc = NULL;
> +	if (mrq->data)
> +		mrq->data->stop = NULL;
> +
> +	/* Firstly check card presence */
> +	present = mmc->ops->get_cd(mmc);
> +
> +	spin_lock_irqsave(&host->lock, flags);
> +
> +	if (sdhci_present_error(host, mrq->cmd, present))
> +		goto out_finish;
> +
> +	cmd = mrq->cmd;
> +
> +	if (!sdhci_uhs2_send_command_retry(host, cmd, flags))
> +		goto out_finish;
> +
> +	spin_unlock_irqrestore(&host->lock, flags);
> +
> +	return;
> +
> +out_finish:
> +	sdhci_finish_mrq(host, mrq);
> +	spin_unlock_irqrestore(&host->lock, flags);
> +}
> +EXPORT_SYMBOL_GPL(sdhci_uhs2_request);
> +
> +int sdhci_uhs2_request_atomic(struct mmc_host *mmc, struct mmc_request *mrq)
> +{
> +	struct sdhci_host *host = mmc_priv(mmc);
> +	struct mmc_command *cmd;
> +	unsigned long flags;
> +	int ret = 0;
> +
> +	if (!sdhci_uhs2_mode(host))
> +		return sdhci_request_atomic(mmc, mrq);
> +
> +	spin_lock_irqsave(&host->lock, flags);
> +
> +	if (sdhci_present_error(host, mrq->cmd, true)) {
> +		sdhci_finish_mrq(host, mrq);
> +		goto out_finish;
> +	}
> +
> +	cmd = mrq->cmd;
> +
> +	/*
> +	 * The HSQ may send a command in interrupt context without polling
> +	 * the busy signaling, which means we should return BUSY if controller
> +	 * has not released inhibit bits to allow HSQ trying to send request
> +	 * again in non-atomic context. So we should not finish this request
> +	 * here.
> +	 */
> +	if (!sdhci_uhs2_send_command(host, cmd))
> +		ret = -EBUSY;
> +
> +out_finish:
> +	spin_unlock_irqrestore(&host->lock, flags);
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(sdhci_uhs2_request_atomic);
> +
>  /*****************************************************************************\
>   *                                                                           *
>   * Driver init/exit                                                          *
> @@ -569,6 +980,7 @@ static int sdhci_uhs2_host_ops_init(struct sdhci_host *host)
>  	host->mmc_host_ops.start_signal_voltage_switch =
>  		sdhci_uhs2_start_signal_voltage_switch;
>  	host->mmc_host_ops.uhs2_control = sdhci_uhs2_control;
> +	host->mmc_host_ops.request = sdhci_uhs2_request;
>  
>  	return 0;
>  }
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 57209accbb03..9d031e83b6ba 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -147,10 +147,11 @@ void sdhci_enable_v4_mode(struct sdhci_host *host)
>  }
>  EXPORT_SYMBOL_GPL(sdhci_enable_v4_mode);
>  
> -static inline bool sdhci_data_line_cmd(struct mmc_command *cmd)
> +bool sdhci_data_line_cmd(struct mmc_command *cmd)
>  {
>  	return cmd->data || cmd->flags & MMC_RSP_BUSY;
>  }
> +EXPORT_SYMBOL_GPL(sdhci_data_line_cmd);
>  
>  static void sdhci_set_card_detection(struct sdhci_host *host, bool enable)
>  {
> @@ -502,14 +503,15 @@ static inline void sdhci_led_deactivate(struct sdhci_host *host)
>  
>  #endif
>  
> -static void sdhci_mod_timer(struct sdhci_host *host, struct mmc_request *mrq,
> -			    unsigned long timeout)
> +void sdhci_mod_timer(struct sdhci_host *host, struct mmc_request *mrq,
> +		     unsigned long timeout)
>  {
>  	if (sdhci_data_line_cmd(mrq->cmd))
>  		mod_timer(&host->data_timer, timeout);
>  	else
>  		mod_timer(&host->timer, timeout);
>  }
> +EXPORT_SYMBOL_GPL(sdhci_mod_timer);
>  
>  static void sdhci_del_timer(struct sdhci_host *host, struct mmc_request *mrq)
>  {
> @@ -1076,8 +1078,7 @@ static void sdhci_set_timeout(struct sdhci_host *host, struct mmc_command *cmd)
>  		__sdhci_set_timeout(host, cmd);
>  }
>  
> -static void sdhci_initialize_data(struct sdhci_host *host,
> -				  struct mmc_data *data)
> +void sdhci_initialize_data(struct sdhci_host *host, struct mmc_data *data)
>  {
>  	WARN_ON(host->data);
>  
> @@ -1090,6 +1091,7 @@ static void sdhci_initialize_data(struct sdhci_host *host,
>  	host->data_early = 0;
>  	host->data->bytes_xfered = 0;
>  }
> +EXPORT_SYMBOL_GPL(sdhci_initialize_data);
>  
>  static inline void sdhci_set_block_info(struct sdhci_host *host,
>  					struct mmc_data *data)
> @@ -1112,12 +1114,8 @@ static inline void sdhci_set_block_info(struct sdhci_host *host,
>  	}
>  }
>  
> -static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_command *cmd)
> +void sdhci_prepare_dma(struct sdhci_host *host, struct mmc_data *data)
>  {
> -	struct mmc_data *data = cmd->data;
> -
> -	sdhci_initialize_data(host, data);
> -
>  	if (host->flags & (SDHCI_USE_SDMA | SDHCI_USE_ADMA)) {
>  		struct scatterlist *sg;
>  		unsigned int length_mask, offset_mask;
> @@ -1202,6 +1200,16 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_command *cmd)
>  	}
>  
>  	sdhci_set_transfer_irqs(host);
> +}
> +EXPORT_SYMBOL_GPL(sdhci_prepare_dma);
> +
> +static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_command *cmd)
> +{
> +	struct mmc_data *data = cmd->data;
> +
> +	sdhci_initialize_data(host, data);
> +
> +	sdhci_prepare_dma(host, data);
>  
>  	sdhci_set_block_info(host, data);
>  }
> @@ -1519,7 +1527,7 @@ static void sdhci_set_mrq_done(struct sdhci_host *host, struct mmc_request *mrq)
>  	WARN_ON(i >= SDHCI_MAX_MRQS);
>  }
>  
> -static void __sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq)
> +void __sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq)
>  {
>  	if (host->cmd && host->cmd->mrq == mrq)
>  		host->cmd = NULL;
> @@ -1543,15 +1551,17 @@ static void __sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq)
>  	if (!sdhci_has_requests(host))
>  		sdhci_led_deactivate(host);
>  }
> +EXPORT_SYMBOL_GPL(__sdhci_finish_mrq);
>  
> -static void sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq)
> +void sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq)
>  {
>  	__sdhci_finish_mrq(host, mrq);
>  
>  	queue_work(host->complete_wq, &host->complete_work);
>  }
> +EXPORT_SYMBOL_GPL(sdhci_finish_mrq);
>  
> -static void __sdhci_finish_data(struct sdhci_host *host, bool sw_data_timeout)
> +void __sdhci_finish_data_common(struct sdhci_host *host)
>  {
>  	struct mmc_command *data_cmd = host->data_cmd;
>  	struct mmc_data *data = host->data;
> @@ -1585,6 +1595,14 @@ static void __sdhci_finish_data(struct sdhci_host *host, bool sw_data_timeout)
>  		data->bytes_xfered = 0;
>  	else
>  		data->bytes_xfered = data->blksz * data->blocks;
> +}
> +EXPORT_SYMBOL_GPL(__sdhci_finish_data_common);
> +
> +static void __sdhci_finish_data(struct sdhci_host *host, bool sw_data_timeout)
> +{
> +	struct mmc_data *data = host->data;
> +
> +	__sdhci_finish_data_common(host);
>  
>  	/*
>  	 * Need to send CMD12 if -
> @@ -1719,8 +1737,8 @@ static bool sdhci_send_command(struct sdhci_host *host, struct mmc_command *cmd)
>  	return true;
>  }
>  
> -static bool sdhci_present_error(struct sdhci_host *host,
> -				struct mmc_command *cmd, bool present)
> +bool sdhci_present_error(struct sdhci_host *host,
> +			 struct mmc_command *cmd, bool present)
>  {
>  	if (!present || host->flags & SDHCI_DEVICE_DEAD) {
>  		cmd->error = -ENOMEDIUM;
> @@ -1729,6 +1747,7 @@ static bool sdhci_present_error(struct sdhci_host *host,
>  
>  	return false;
>  }
> +EXPORT_SYMBOL_GPL(sdhci_present_error);
>  
>  static bool sdhci_send_command_retry(struct sdhci_host *host,
>  				     struct mmc_command *cmd,
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> index 03d29423a678..9a2bd319d94c 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -828,6 +828,14 @@ static inline void sdhci_read_caps(struct sdhci_host *host)
>  	__sdhci_read_caps(host, NULL, NULL, NULL);
>  }
>  
> +bool sdhci_data_line_cmd(struct mmc_command *cmd);
> +void sdhci_mod_timer(struct sdhci_host *host, struct mmc_request *mrq, unsigned long timeout);
> +void sdhci_initialize_data(struct sdhci_host *host, struct mmc_data *data);
> +void sdhci_prepare_dma(struct sdhci_host *host, struct mmc_data *data);
> +void __sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq);
> +void sdhci_finish_mrq(struct sdhci_host *host, struct mmc_request *mrq);
> +void __sdhci_finish_data_common(struct sdhci_host *host);
> +bool sdhci_present_error(struct sdhci_host *host, struct mmc_command *cmd, bool present);
>  u16 sdhci_calc_clk(struct sdhci_host *host, unsigned int clock,
>  		   unsigned int *actual_clock);
>  void sdhci_set_clock(struct sdhci_host *host, unsigned int clock);