From: Kevin Liu Date: Sat, 5 Jan 2013 09:18:28 +0000 (+0800) Subject: mmc: sdhci: disable interrupt before free_irq X-Git-Tag: firefly_0821_release~3680^2~988^2~58^2~8 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=f6f926885faa07aa9f54617b4e59fa33074500f5;p=firefly-linux-kernel-4.4.55.git mmc: sdhci: disable interrupt before free_irq Current code missed disabling interrupts before free irq which is shared. Notice below comments for function free_irq (kernel/irq/manage.c): On a shared IRQ the caller must ensure the interrupt is disabled on the card it drives before calling this function. Original code has below issue during suspend/resume when multiple SD hosts share the same IRQ: 1. Assume there are two hosts (host1 for emmc while host2 for sd) share the same mmc irq. 2. When system suspend, host2 will be suspended before host1. So the sequence is below: step1: irq handler for host2 removed -> step2: irq handler for host1 removed and irq disabled -> ... system suspended ... ... system resumed ... step3: irq enabled and the irq handler for host1 restored -> step4: irq handler for host2 restored 3. So there is the buggy time slot that the irq is enabled but the irq handler for host2 is removed. Then host2 interrupt can be triggered but can't be handled at that moment. Signed-off-by: Jialing Fu Signed-off-by: Kevin Liu Signed-off-by: Chris Ball --- diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 1b97fe2d70ab..1165376592b9 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -2487,6 +2487,7 @@ int sdhci_suspend_host(struct sdhci_host *host) return ret; } + sdhci_mask_irqs(host, SDHCI_INT_ALL_MASK); free_irq(host->irq, host); return ret; @@ -3142,6 +3143,7 @@ int sdhci_add_host(struct sdhci_host *host) #ifdef SDHCI_USE_LEDS_CLASS reset: sdhci_reset(host, SDHCI_RESET_ALL); + sdhci_mask_irqs(host, SDHCI_INT_ALL_MASK); free_irq(host->irq, host); #endif untasklet: @@ -3184,6 +3186,7 @@ void sdhci_remove_host(struct sdhci_host *host, int dead) if (!dead) sdhci_reset(host, SDHCI_RESET_ALL); + sdhci_mask_irqs(host, SDHCI_INT_ALL_MASK); free_irq(host->irq, host); del_timer_sync(&host->timer);