From 235f1eb1ab93a8e30a66c38949e6d2aeda136aec Mon Sep 17 00:00:00 2001 From: Grygorii Strashko Date: Tue, 18 Aug 2015 14:10:55 +0300 Subject: [PATCH] gpio: omap: protect regs access in omap_gpio_irq_handler The access to HW registers has to be be protected in omap_gpio_irq_handler(), as it may race with code executed on another CPUs. Signed-off-by: Grygorii Strashko Acked-by: Santosh Shilimkar Tested-by: Tony Lindgren Signed-off-by: Linus Walleij --- drivers/gpio/gpio-omap.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c index 9ed5a675564c..1f02acd577e3 100644 --- a/drivers/gpio/gpio-omap.c +++ b/drivers/gpio/gpio-omap.c @@ -718,6 +718,7 @@ static void omap_gpio_irq_handler(unsigned int irq, struct irq_desc *desc) int unmasked = 0; struct irq_chip *irqchip = irq_desc_get_chip(desc); struct gpio_chip *chip = irq_desc_get_handler_data(desc); + unsigned long lock_flags; chained_irq_enter(irqchip, desc); @@ -732,6 +733,8 @@ static void omap_gpio_irq_handler(unsigned int irq, struct irq_desc *desc) u32 isr_saved, level_mask = 0; u32 enabled; + raw_spin_lock_irqsave(&bank->lock, lock_flags); + enabled = omap_get_gpio_irqbank_mask(bank); isr_saved = isr = readl_relaxed(isr_reg) & enabled; @@ -745,6 +748,8 @@ static void omap_gpio_irq_handler(unsigned int irq, struct irq_desc *desc) omap_clear_gpio_irqbank(bank, isr_saved & ~level_mask); omap_enable_gpio_irqbank(bank, isr_saved & ~level_mask); + raw_spin_unlock_irqrestore(&bank->lock, lock_flags); + /* if there is only edge sensitive GPIO pin interrupts configured, we could unmask GPIO bank interrupt immediately */ if (!level_mask && !unmasked) { @@ -759,6 +764,7 @@ static void omap_gpio_irq_handler(unsigned int irq, struct irq_desc *desc) bit = __ffs(isr); isr &= ~(BIT(bit)); + raw_spin_lock_irqsave(&bank->lock, lock_flags); /* * Some chips can't respond to both rising and falling * at the same time. If this irq was requested with @@ -769,6 +775,8 @@ static void omap_gpio_irq_handler(unsigned int irq, struct irq_desc *desc) if (bank->toggle_mask & (BIT(bit))) omap_toggle_gpio_edge_triggering(bank, bit); + raw_spin_unlock_irqrestore(&bank->lock, lock_flags); + generic_handle_irq(irq_find_mapping(bank->chip.irqdomain, bit)); } -- 2.39.5