mmc: Delay the card_event callback into the mmc_rescan worker

This change removes the callback from atomic context which it doesn't
need to be in, and puts it in line with the debounced rescan.

This code is based on these e-mail threads with Christian Daudt:

  https://lkml.org/lkml/2013/8/19/539
  https://lkml.org/lkml/2014/3/19/79

Signed-off-by: Markus Mayer <markus.mayer@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index acbc3f2..f396d1b 100644 (file)
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -2403,6 +2403,11 @@ void mmc_rescan(struct work_struct *work)
                container_of(work, struct mmc_host, detect.work);
        int i;
 
+       if (host->trigger_card_event && host->ops->card_event) {
+               host->ops->card_event(host);
+               host->trigger_card_event = false;
+       }
+
        if (host->rescan_disable)
                return;
 

diff --git a/drivers/mmc/core/slot-gpio.c b/drivers/mmc/core/slot-gpio.c
index f7650b8..5f89cb8 100644 (file)
--- a/drivers/mmc/core/slot-gpio.c
+++ b/drivers/mmc/core/slot-gpio.c
@@ -32,9 +32,7 @@ static irqreturn_t mmc_gpio_cd_irqt(int irq, void *dev_id)
        /* Schedule a card detection after a debounce timeout */
        struct mmc_host *host = dev_id;
 
-       if (host->ops->card_event)
-               host->ops->card_event(host);
-
+       host->trigger_card_event = true;
        mmc_detect_change(host, msecs_to_jiffies(200));
 
        return IRQ_HANDLED;

diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 3535420..0cf705c 100644 (file)
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -319,6 +319,8 @@ struct mmc_host {
        int                     rescan_disable; /* disable card detection */
        int                     rescan_entered; /* used with nonremovable devices */
 
+       bool                    trigger_card_event; /* card_event necessary */
+
        struct mmc_card         *card;          /* device attached to this host */
 
        wait_queue_head_t       wq;