linux-kernel - [PATCH 05/11] mmc: core: Clarify sdio_irq_pending flag for MMC_CAP2_SDIO_IRQ

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Date:   Tue,  3 Sep 2019 16:22:01 +0200
From:   Ulf Hansson <ulf.hansson@...aro.org>
To:     linux-mmc@...r.kernel.org, Ulf Hansson <ulf.hansson@...aro.org>,
        Adrian Hunter <adrian.hunter@...el.com>,
        Douglas Anderson <dianders@...omium.org>,
        Matthias Kaehlcke <mka@...omium.org>
Cc:     Shawn Lin <shawn.lin@...k-chips.com>,
        Jaehoon Chung <jh80.chung@...sung.com>,
        Yong Mao <yong.mao@...iatek.com>,
        Chaotian Jing <chaotian.jing@...iatek.com>,
        linux-kernel@...r.kernel.org
Subject: [PATCH 05/11] mmc: core: Clarify sdio_irq_pending flag for MMC_CAP2_SDIO_IRQ_NOTHREAD

In the single SDIO IRQ handler case, the sdio_irq_pending flag is used to
avoid reading the SDIO_CCCR_INTx register and instead immediately call the
SDIO func's >irq_handler() callback.

To clarify the use behind the flag for the MMC_CAP2_SDIO_IRQ_NOTHREAD case,
let's set the flag from inside sdio_signal_irq(), rather from
sdio_run_irqs(). Moreover, let's also reset the flag when the SDIO IRQ have
been properly processed.

Signed-off-by: Ulf Hansson <ulf.hansson@...aro.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 f75043266984..0962a4357d54 100644
--- a/drivers/mmc/core/sdio_irq.c
+++ b/drivers/mmc/core/sdio_irq.c
@@ -59,6 +59,7 @@ 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;
 
@@ -66,13 +67,16 @@ 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;
 	}
@@ -110,7 +114,6 @@ 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);
@@ -128,6 +131,7 @@ 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);
@@ -173,7 +177,6 @@ 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);
 
 		/*
-- 
2.17.1