[PATCH RESEND] mmc: Delay the card_event callback into the mmc_rescan worker

[Markus Mayer <markus.mayer@linaro.org>]

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>
---
 drivers/mmc/core/core.c      |    5 +++++
 drivers/mmc/core/slot-gpio.c |    4 +---
 include/linux/mmc/host.h     |    2 ++
 3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 098374b..ff7fd2e 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -2421,6 +2421,11 @@ 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 46596b71..4029c85 100644
--- a/drivers/mmc/core/slot-gpio.c
+++ b/drivers/mmc/core/slot-gpio.c
@@ -29,9 +29,7 @@ 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 99f5709..63b983b 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -322,6 +322,8 @@ 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;
-- 
1.7.9.5