From: Ulf Hansson ulf.hansson@linaro.org
[ Upstream commit 36d57efb4af534dd6b442ea0b9a04aa6dfa37abe ]
The sdio_irq_pending flag is used to let host drivers indicate that it has signaled an IRQ. If that is the case and we only have a single SDIO func that have claimed an SDIO IRQ, our assumption is that we can avoid reading the SDIO_CCCR_INTx register and just call the SDIO func irq handler immediately. This makes sense, but the flag is set/cleared in a somewhat messy order, let's fix that up according to below.
First, the flag is currently set in sdio_run_irqs(), which is executed as a work that was scheduled from sdio_signal_irq(). To make it more implicit that the host have signaled an IRQ, let's instead immediately set the flag in sdio_signal_irq(). This also makes the behavior consistent with host drivers that uses the legacy, mmc_signal_sdio_irq() API. This have no functional impact, because we don't expect host drivers to call sdio_signal_irq() until after the work (sdio_run_irqs()) have been executed anyways.
Second, currently we never clears the flag when using the sdio_run_irqs() work, but only when using the sdio_irq_thread(). Let make the behavior consistent, by moving the flag to be cleared inside the common process_sdio_pending_irqs() function. Additionally, tweak the behavior of the flag slightly, by avoiding to clear it unless we processed the SDIO IRQ. The purpose with this at this point, is to keep the information about whether there have been an SDIO IRQ signaled by the host, so at system resume we can decide to process it without reading the SDIO_CCCR_INTx register.
Tested-by: Matthias Kaehlcke mka@chromium.org Reviewed-by: Matthias Kaehlcke mka@chromium.org Signed-off-by: Ulf Hansson ulf.hansson@linaro.org Reviewed-by: Douglas Anderson dianders@chromium.org Signed-off-by: Ulf Hansson ulf.hansson@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/mmc/core/sdio_irq.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/mmc/core/sdio_irq.c b/drivers/mmc/core/sdio_irq.c index 0bcc5e83bd1a0..40109a6159228 100644 --- a/drivers/mmc/core/sdio_irq.c +++ b/drivers/mmc/core/sdio_irq.c @@ -31,6 +31,7 @@ static int process_sdio_pending_irqs(struct mmc_host *host) { struct mmc_card *card = host->card; int i, ret, count; + bool sdio_irq_pending = host->sdio_irq_pending; unsigned char pending; struct sdio_func *func;
@@ -38,13 +39,16 @@ static int process_sdio_pending_irqs(struct mmc_host *host) if (mmc_card_suspended(card)) return 0;
+ /* Clear the flag to indicate that we have processed the IRQ. */ + host->sdio_irq_pending = false; + /* * Optimization, if there is only 1 function interrupt registered * and we know an IRQ was signaled then call irq handler directly. * Otherwise do the full probe. */ func = card->sdio_single_irq; - if (func && host->sdio_irq_pending) { + if (func && sdio_irq_pending) { func->irq_handler(func); return 1; } @@ -96,7 +100,6 @@ static void sdio_run_irqs(struct mmc_host *host) { mmc_claim_host(host); if (host->sdio_irqs) { - host->sdio_irq_pending = true; process_sdio_pending_irqs(host); if (host->ops->ack_sdio_irq) host->ops->ack_sdio_irq(host); @@ -114,6 +117,7 @@ void sdio_irq_work(struct work_struct *work)
void sdio_signal_irq(struct mmc_host *host) { + host->sdio_irq_pending = true; queue_delayed_work(system_wq, &host->sdio_irq_work, 0); } EXPORT_SYMBOL_GPL(sdio_signal_irq); @@ -159,7 +163,6 @@ static int sdio_irq_thread(void *_host) if (ret) break; ret = process_sdio_pending_irqs(host); - host->sdio_irq_pending = false; mmc_release_host(host);
/*