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.

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>

5 files changed, 83 insertions, 6 deletions

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 950b97d7412a..a2aa860956ef 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -140,7 +140,7 @@ 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)) {
                 /*
                  * Request starter must handle retries - see
                  * mmc_wait_for_req_done().
@@ -247,6 +247,11 @@ static void __mmc_start_req(struct mmc_host *host, struct mmc_request *mrq)
 {
         init_completion(&mrq->completion);
         mrq->done = mmc_wait_done;
+        if (mmc_card_removed(host->card)) {
+                mrq->cmd->error = -ENOMEDIUM;
+                complete(&mrq->completion);
+                return;
+        }
         mmc_start_request(host, mrq);
 }
 
@@ -259,7 +264,8 @@ static void mmc_wait_for_req_done(struct mmc_host *host,
                 wait_for_completion(&mrq->completion);
 
                 cmd = mrq->cmd;
-                if (!cmd->error || !cmd->retries)
+                if (!cmd->error || !cmd->retries ||
+                    mmc_card_removed(host->card))
                         break;
 
                 pr_debug("%s: req failed (CMD%u): %d, retrying...\n",
@@ -1456,7 +1462,7 @@ void mmc_detect_change(struct mmc_host *host, unsigned long delay)
         WARN_ON(host->removed);
         spin_unlock_irqrestore(&host->lock, flags);
 #endif
-
+        host->detect_change = 1;
         mmc_schedule_delayed_work(&host->detect, delay);
 }
 
@@ -2049,6 +2055,43 @@ 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)
 {
         static const unsigned freqs[] = { 400000, 300000, 200000, 100000 };
@@ -2069,6 +2112,8 @@ void mmc_rescan(struct work_struct *work)
             && !(host->caps & MMC_CAP_NONREMOVABLE))
                 host->bus_ops->detect(host);
 
+        host->detect_change = 0;
+
         /*
          * Let mmc_bus_put() free the bus/bus_ops if we've found that
          * the card is no longer present.
diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h
index 14664f1fb16f..34009241213c 100644
--- a/drivers/mmc/core/core.h
+++ b/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);
@@ -59,6 +60,8 @@ 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);
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index d240427c1246..fc1059bb6a08 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1105,6 +1105,14 @@ static void mmc_remove(struct mmc_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.
  */
 static void mmc_detect(struct mmc_host *host)
@@ -1119,7 +1127,7 @@ 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);
 
@@ -1224,6 +1232,7 @@ 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 = {
@@ -1234,6 +1243,7 @@ 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)
diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index 85b858f6d5d4..6f27d35081b8 100644
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -1019,6 +1019,14 @@ static void mmc_sd_remove(struct mmc_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.
  */
 static void mmc_sd_detect(struct mmc_host *host)
@@ -1033,7 +1041,7 @@ static void mmc_sd_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);
 
@@ -1102,6 +1110,7 @@ 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 = {
@@ -1110,6 +1119,7 @@ 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)
diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index 8c04f7f46dec..b77f770ce5d1 100644
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -820,6 +820,14 @@ static void mmc_sdio_remove(struct mmc_host *host)
 }
 
 /*
+ * 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.
  */
 static void mmc_sdio_detect(struct mmc_host *host)
@@ -841,7 +849,7 @@ 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);
 
@@ -1019,6 +1027,7 @@ 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,
 };