Commit 56f6911c authored by Shawn Lin's avatar Shawn Lin Committed by Ulf Hansson
Browse files

mmc: dw_mmc: check card present before starting request 



The main reason to add this check is to avoid unnecessary
mmc_request like the on-going cmd and the corresponding sbc
if the card is removed. Although we have already checked this in
dw_mci_handle_cd for runtime usage of sd card and dw_mci_init_slot
for noremovable devices, but there is a timing gap before it really
calls dw_mci_get_cd as mmc_detect_change needs some delay here.

Another gain here is that we could save some checkings of card status
after sd card been removed.

Signed-off-by: default avatarShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: default avatarJaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent c0834a58

drivers/mmc/host/dw_mmc.c

+4 −3
Original line number Original line Diff line number Diff line
@@ -105,6 +105,7 @@ struct idmac_desc { 
static bool dw_mci_reset(struct dw_mci *host);

static bool dw_mci_reset(struct dw_mci *host);

static bool dw_mci_ctrl_reset(struct dw_mci *host, u32 reset);

static bool dw_mci_ctrl_reset(struct dw_mci *host, u32 reset);

static int dw_mci_card_busy(struct mmc_host *mmc);

static int dw_mci_card_busy(struct mmc_host *mmc);

static int dw_mci_get_cd(struct mmc_host *mmc);





#if defined(CONFIG_DEBUG_FS)

#if defined(CONFIG_DEBUG_FS)

static int dw_mci_req_show(struct seq_file *s, void *v)

static int dw_mci_req_show(struct seq_file *s, void *v)
@@ -1253,15 +1254,15 @@ static void dw_mci_request(struct mmc_host *mmc, struct mmc_request *mrq) 
	 * atomic, otherwise the card could be removed in between and the

	 * atomic, otherwise the card could be removed in between and the

	 * request wouldn't fail until another card was inserted.

	 * request wouldn't fail until another card was inserted.

	 */

	 */

	spin_lock_bh(&host->lock);





	if (!test_bit(DW_MMC_CARD_PRESENT, &slot->flags)) {

	if (!dw_mci_get_cd(mmc)) {

		spin_unlock_bh(&host->lock);

		mrq->cmd->error = -ENOMEDIUM;

		mrq->cmd->error = -ENOMEDIUM;

		mmc_request_done(mmc, mrq);

		mmc_request_done(mmc, mrq);

		return;

		return;

	}

	}





	spin_lock_bh(&host->lock);



	dw_mci_queue_request(host, slot, mrq);

	dw_mci_queue_request(host, slot, mrq);





	spin_unlock_bh(&host->lock);

	spin_unlock_bh(&host->lock);

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