mmc: allow upper layers to know immediately if card has been removed

Add a function mmc_detect_card_removed() which upper layers can use to
determine immediately if a card has been removed. This function should
be called after an I/O request fails so that all queued I/O requests
can be errored out immediately instead of waiting for the card device
to be removed.

Change-Id: Iad4806319b6ad67048674adfdd919458186521d6
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
[sthumma@codeaurora.org: Fixed merge conflicts]
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>

drivers/mmc/core/core.c

@@ -105,7 +105,7 @@ void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
 			cmd->retries = 0;
 	}
 
-	if (err && cmd->retries) {
+	if (err && cmd->retries && !mmc_card_removed(host->card)) {
 		pr_debug("%s: req failed (CMD%u): %d, retrying...\n",
 			mmc_hostname(host), cmd->opcode, err);
 
@@ -238,6 +238,10 @@ void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq)
 
 	mrq->done_data = &complete;
 	mrq->done = mmc_wait_done;
+	if (mmc_card_removed(host->card)) {
+		mrq->cmd->error = -ENOMEDIUM;
+		return;
+	}
 
 	mmc_start_request(host, mrq);
 
@@ -1250,6 +1254,7 @@ void mmc_detect_change(struct mmc_host *host, unsigned long delay)
 #endif
 
 	wake_lock(&host->detect_wake_lock);
+	host->detect_change = 1;
 	mmc_schedule_delayed_work(&host->detect, delay);
 }
 
@@ -1658,6 +1663,43 @@ static int mmc_rescan_try_freq(struct mmc_host *host, unsigned freq)
 	return -EIO;
 }
 
+int _mmc_detect_card_removed(struct mmc_host *host)
+{
+	int ret;
+
+	if ((host->caps & MMC_CAP_NONREMOVABLE) || !host->bus_ops->alive)
+		return 0;
+
+	if (!host->card || mmc_card_removed(host->card))
+		return 1;
+
+	ret = host->bus_ops->alive(host);
+	if (ret) {
+		mmc_card_set_removed(host->card);
+		pr_debug("%s: card remove detected\n", mmc_hostname(host));
+	}
+
+	return ret;
+}
+
+int mmc_detect_card_removed(struct mmc_host *host)
+{
+	struct mmc_card *card = host->card;
+
+	WARN_ON(!host->claimed);
+	/*
+	 * The card will be considered unchanged unless we have been asked to
+	 * detect a change or host requires polling to provide card detection.
+	 */
+	if (card && !host->detect_change && !(host->caps & MMC_CAP_NEEDS_POLL))
+		return mmc_card_removed(card);
+
+	host->detect_change = 0;
+
+	return _mmc_detect_card_removed(host);
+}
+EXPORT_SYMBOL(mmc_detect_card_removed);
+
 void mmc_rescan(struct work_struct *work)
 {
 	struct mmc_host *host =
@@ -1683,6 +1725,8 @@ void mmc_rescan(struct work_struct *work)
 	if (host->bus_dead)
 		extend_wakelock = 1;
 
+	host->detect_change = 0;
+
 	/*
 	 * Let mmc_bus_put() free the bus/bus_ops if we've found that
 	 * the card is no longer present.

drivers/mmc/core/core.h

@@ -24,6 +24,7 @@ struct mmc_bus_ops {
 	int (*resume)(struct mmc_host *);
 	int (*power_save)(struct mmc_host *);
 	int (*power_restore)(struct mmc_host *);
+	int (*alive)(struct mmc_host *);
 };
 
 void mmc_attach_bus(struct mmc_host *host, const struct mmc_bus_ops *ops);
@@ -60,6 +61,8 @@ void mmc_rescan(struct work_struct *work);
 void mmc_start_host(struct mmc_host *host);
 void mmc_stop_host(struct mmc_host *host);
 
+int _mmc_detect_card_removed(struct mmc_host *host);
+
 int mmc_attach_mmc(struct mmc_host *host);
 int mmc_attach_sd(struct mmc_host *host);
 int mmc_attach_sdio(struct mmc_host *host);

drivers/mmc/core/mmc.c

@@ -873,6 +873,14 @@ static void mmc_remove(struct mmc_host *host)
 	mmc_release_host(host);
 }
 
+/*
+ * Card detection - card is alive.
+ */
+static int mmc_alive(struct mmc_host *host)
+{
+	return mmc_send_status(host->card, NULL);
+}
+
 /*
  * Card detection callback from host.
  */
@@ -888,7 +896,7 @@ static void mmc_detect(struct mmc_host *host)
 	/*
 	 * Just check if our card has been removed.
 	 */
-	err = mmc_send_status(host->card, NULL);
+	err = _mmc_detect_card_removed(host);
 
 	mmc_release_host(host);
 
@@ -992,6 +1000,7 @@ static const struct mmc_bus_ops mmc_ops = {
 	.suspend = NULL,
 	.resume = NULL,
 	.power_restore = mmc_power_restore,
+	.alive = mmc_alive,
 };
 
 static const struct mmc_bus_ops mmc_ops_unsafe = {
@@ -1002,6 +1011,7 @@ static const struct mmc_bus_ops mmc_ops_unsafe = {
 	.suspend = mmc_suspend,
 	.resume = mmc_resume,
 	.power_restore = mmc_power_restore,
+	.alive = mmc_alive,
 };
 
 static void mmc_attach_bus_ops(struct mmc_host *host)

drivers/mmc/core/sd.c

@@ -1043,6 +1043,14 @@ static void mmc_sd_remove(struct mmc_host *host)
 	mmc_release_host(host);
 }
 
+/*
+ * Card detection - card is alive.
+ */
+static int mmc_sd_alive(struct mmc_host *host)
+{
+	return mmc_send_status(host->card, NULL);
+}
+
 /*
  * Card detection callback from host.
  */
@@ -1063,7 +1071,7 @@ static void mmc_sd_detect(struct mmc_host *host)
 	 */
 #ifdef CONFIG_MMC_PARANOID_SD_INIT
 	while(retries) {
-		err = mmc_send_status(host->card, NULL);
+		err = _mmc_detect_card_removed(host);
 		if (err) {
 			retries--;
 			udelay(5);
@@ -1076,7 +1084,7 @@ static void mmc_sd_detect(struct mmc_host *host)
 		       __func__, mmc_hostname(host), err);
 	}
 #else
-	err = mmc_send_status(host->card, NULL);
+	err = _mmc_detect_card_removed(host);
 #endif
 	mmc_release_host(host);
 
@@ -1163,6 +1171,7 @@ static const struct mmc_bus_ops mmc_sd_ops = {
 	.suspend = NULL,
 	.resume = NULL,
 	.power_restore = mmc_sd_power_restore,
+	.alive = mmc_sd_alive,
 };
 
 static const struct mmc_bus_ops mmc_sd_ops_unsafe = {
@@ -1171,6 +1180,7 @@ static const struct mmc_bus_ops mmc_sd_ops_unsafe = {
 	.suspend = mmc_sd_suspend,
 	.resume = mmc_sd_resume,
 	.power_restore = mmc_sd_power_restore,
+	.alive = mmc_sd_alive,
 };
 
 static void mmc_sd_attach_bus_ops(struct mmc_host *host)

drivers/mmc/core/sdio.c

@@ -581,6 +581,14 @@ static void mmc_sdio_remove(struct mmc_host *host)
 	host->card = NULL;
 }
 
+/*
+ * Card detection - card is alive.
+ */
+static int mmc_sdio_alive(struct mmc_host *host)
+{
+	return mmc_select_card(host->card);
+}
+
 /*
  * Card detection callback from host.
  */
@@ -603,7 +611,7 @@ static void mmc_sdio_detect(struct mmc_host *host)
 	/*
 	 * Just check if our card has been removed.
 	 */
-	err = mmc_select_card(host->card);
+	err = _mmc_detect_card_removed(host);
 
 	mmc_release_host(host);
 
@@ -783,6 +791,7 @@ static const struct mmc_bus_ops mmc_sdio_ops = {
 	.suspend = mmc_sdio_suspend,
 	.resume = mmc_sdio_resume,
 	.power_restore = mmc_sdio_power_restore,
+	.alive = mmc_sdio_alive,
 };
 
 

include/linux/mmc/card.h

@@ -177,6 +177,7 @@ struct mmc_card {
 #define MMC_STATE_HIGHSPEED_DDR (1<<4)		/* card is in high speed mode */
 #define MMC_STATE_ULTRAHIGHSPEED (1<<5)		/* card is in ultra high speed mode */
 #define MMC_CARD_SDXC		(1<<6)		/* card is SDXC */
+#define MMC_CARD_REMOVED	(1<<7)		/* card has been removed */
 	unsigned int		quirks; 	/* card quirks */
 #define MMC_QUIRK_LENIENT_FN0	(1<<0)		/* allow SDIO FN0 writes outside of the VS CCCR range */
 #define MMC_QUIRK_BLKSZ_FOR_BYTE_MODE (1<<1)	/* use func->cur_blksize */
@@ -314,6 +315,7 @@ static inline void __maybe_unused remove_quirk(struct mmc_card *card, int data)
 #define mmc_card_ddr_mode(c)	((c)->state & MMC_STATE_HIGHSPEED_DDR)
 #define mmc_sd_card_uhs(c) ((c)->state & MMC_STATE_ULTRAHIGHSPEED)
 #define mmc_card_ext_capacity(c) ((c)->state & MMC_CARD_SDXC)
+#define mmc_card_removed(c)	((c) && ((c)->state & MMC_CARD_REMOVED))
 
 #define mmc_card_set_present(c)	((c)->state |= MMC_STATE_PRESENT)
 #define mmc_card_set_readonly(c) ((c)->state |= MMC_STATE_READONLY)
@@ -322,6 +324,7 @@ static inline void __maybe_unused remove_quirk(struct mmc_card *card, int data)
 #define mmc_card_set_ddr_mode(c) ((c)->state |= MMC_STATE_HIGHSPEED_DDR)
 #define mmc_sd_card_set_uhs(c) ((c)->state |= MMC_STATE_ULTRAHIGHSPEED)
 #define mmc_card_set_ext_capacity(c) ((c)->state |= MMC_CARD_SDXC)
+#define mmc_card_set_removed(c) ((c)->state |= MMC_CARD_REMOVED)
 
 /*
  * Quirk add/remove for MMC products.

include/linux/mmc/core.h

@@ -166,6 +166,8 @@ extern void mmc_release_host(struct mmc_host *host);
 extern void mmc_do_release_host(struct mmc_host *host);
 extern int mmc_try_claim_host(struct mmc_host *host);
 
+extern int mmc_detect_card_removed(struct mmc_host *host);
+
 /**
  *	mmc_claim_host - exclusively claim a host
  *	@host: mmc host to claim

include/linux/mmc/host.h

@@ -266,6 +266,7 @@ struct mmc_host {
 
 	struct delayed_work	detect;
 	struct wake_lock	detect_wake_lock;
+	int                     detect_change;  /* card detect flag */
 
 	const struct mmc_bus_ops *bus_ops;	/* current bus driver */
 	unsigned int		bus_refs;	/* reference counter */