Commit bbbc4c4d authored by Nicolas Pitre's avatar Nicolas Pitre Committed by Chris Ball
Browse files

mmc: sdio: avoid spurious calls to interrupt handlers 



Commit 06e8935f ("optimized SDIO IRQ handling for single irq")
introduced some spurious calls to SDIO function interrupt handlers,
such as when the SDIO IRQ thread is started, or the safety check
performed upon a system resume.  Let's add a flag to perform the
optimization only when a real interrupt is signaled by the host
driver and we know there is no point confirming it.

Reported-by: default avatarSujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: default avatarNicolas Pitre <nico@linaro.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: default avatarChris Ball <cjb@laptop.org>
parent 6187fee4

drivers/mmc/core/sdio.c

+1 −1
Original line number Diff line number Diff line
@@ -947,7 +947,7 @@ static int mmc_sdio_resume(struct mmc_host *host) 
	}



	if (!err && host->sdio_irqs)

		mmc_signal_sdio_irq(host);

		wake_up_process(host->sdio_irq_thread);

	mmc_release_host(host);



	/*

drivers/mmc/core/sdio_irq.c

+7 −4
Original line number Diff line number Diff line
@@ -28,18 +28,20 @@ 


#include "sdio_ops.h"



static int process_sdio_pending_irqs(struct mmc_card *card)

static int process_sdio_pending_irqs(struct mmc_host *host)

{

	struct mmc_card *card = host->card;

	int i, ret, count;

	unsigned char pending;

	struct sdio_func *func;



	/*

	 * Optimization, if there is only 1 function interrupt registered

	 * call irq handler directly

	 * and we know an IRQ was signaled then call irq handler directly.

	 * Otherwise do the full probe.

	 */

	func = card->sdio_single_irq;

	if (func) {

	if (func && host->sdio_irq_pending) {

		func->irq_handler(func);

		return 1;

	}
@@ -116,7 +118,8 @@ static int sdio_irq_thread(void *_host) 
		ret = __mmc_claim_host(host, &host->sdio_irq_thread_abort);

		if (ret)

			break;

		ret = process_sdio_pending_irqs(host->card);

		ret = process_sdio_pending_irqs(host);

		host->sdio_irq_pending = false;

		mmc_release_host(host);



		/*

include/linux/mmc/host.h

+2 −0
Original line number Diff line number Diff line
@@ -297,6 +297,7 @@ struct mmc_host { 


	unsigned int		sdio_irqs;

	struct task_struct	*sdio_irq_thread;

	bool			sdio_irq_pending;

	atomic_t		sdio_irq_thread_abort;



	mmc_pm_flag_t		pm_flags;	/* requested pm features */
@@ -352,6 +353,7 @@ extern int mmc_cache_ctrl(struct mmc_host *, u8); 
static inline void mmc_signal_sdio_irq(struct mmc_host *host)

{

	host->ops->enable_sdio_irq(host, 0);

	host->sdio_irq_pending = true;

	wake_up_process(host->sdio_irq_thread);

}

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