bcm2835-mmc: Add locks when accessing sdhost registers

raspberrypi · May 1, 2015 · 547b736 · 547b736
1 parent 39315a8
commit 547b736
Showing 1 changed file with 12 additions and 0 deletions.
diff --git a/drivers/mmc/host/bcm2835-mmc.c b/drivers/mmc/host/bcm2835-mmc.c
@@ -344,7 +344,11 @@ static void bcm2835_mmc_dumpregs(struct bcm2835_host *host)
 static void bcm2835_mmc_reset(struct bcm2835_host *host, u8 mask)
 {
 	unsigned long timeout;
+	unsigned long flags;
+
+	BUG_ON(spin_is_locked(&host->lock));
 
+	spin_lock_irqsave(&host->lock, flags);
 	bcm2835_mmc_writeb(host, mask, SDHCI_SOFTWARE_RESET, 0);
 
 	if (mask & SDHCI_RESET_ALL)
@@ -362,7 +366,9 @@ static void bcm2835_mmc_reset(struct bcm2835_host *host, u8 mask)
 			goto exit;
 		}
 		timeout--;
+		spin_unlock_irqrestore(&host->lock, flags);
 		mdelay(1);
+		spin_lock_irqsave(&host->lock, flags);
 	}
 
 	if (100-timeout > 10 && 100-timeout > host->max_delay) {
@@ -372,12 +378,14 @@ static void bcm2835_mmc_reset(struct bcm2835_host *host, u8 mask)
 exit:
 	if ((mmc_debug & (1<<15)))
 		bcm2835_mmc_writeb(host, TIMEOUT_VAL, SDHCI_TIMEOUT_CONTROL, 1);
+	spin_unlock_irqrestore(&host->lock, flags);
 }
 
 static void bcm2835_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios);
 
 static void bcm2835_mmc_init(struct bcm2835_host *host, int soft)
 {
+	unsigned long flags;
 	if (soft)
 		bcm2835_mmc_reset(host, SDHCI_RESET_CMD|SDHCI_RESET_DATA);
 	else
@@ -389,8 +397,10 @@ static void bcm2835_mmc_init(struct bcm2835_host *host, int soft)
 		    SDHCI_INT_TIMEOUT | SDHCI_INT_DATA_END |
 		    SDHCI_INT_RESPONSE;
 
+	spin_lock_irqsave(&host->lock, flags);
 	bcm2835_mmc_writel(host, host->ier, SDHCI_INT_ENABLE, 3);
 	bcm2835_mmc_writel(host, host->ier, SDHCI_SIGNAL_ENABLE, 3);
+	spin_unlock_irqrestore(&host->lock, flags);
 
 	if (soft) {
 		/* force clock reconfiguration */
@@ -1339,8 +1349,10 @@ static void bcm2835_mmc_tasklet_finish(unsigned long param)
 		 (mrq->data && (mrq->data->error ||
 		  (mrq->data->stop && mrq->data->stop->error))))) {
 
+		spin_unlock_irqrestore(&host->lock, flags);
 		bcm2835_mmc_reset(host, SDHCI_RESET_CMD);
 		bcm2835_mmc_reset(host, SDHCI_RESET_DATA);
+		spin_lock_irqsave(&host->lock, flags);
 	}
 
 	host->mrq = NULL;