From 3d009c8c61f96b50c068c8122e929352c359f877 Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Fri, 16 Jan 2015 14:50:50 -0800 Subject: [PATCH] gpio: omap: Fix bad device access with setup_irq() Similar to omap_gpio_irq_type() let's make sure that the GPIO is usable as an interrupt if the platform init code did not call gpio_request(). Otherwise we can get invalid device access after setup_irq(): WARNING: CPU: 0 PID: 1 at drivers/bus/omap_l3_noc.c:147 l3_interrupt_handler+0x214/0x340() 44000000.ocp:L3 Custom Error: MASTER MPU TARGET L4CFG (Idle): Data Access in Supervisor mode during Functional access ... [] (__irq_svc) from [] (_raw_spin_unlock_irqrestore+0x34/0x44) [] (_raw_spin_unlock_irqrestore) from [] (__setup_irq+0x244/0x530) [] (__setup_irq) from [] (setup_irq+0x40/0x8c) [] (setup_irq) from [] (omap_system_dma_probe+0x1d4/0x2b4) [] (omap_system_dma_probe) from [] (platform_drv_probe+0x44/0xa4) ... We can fix this the same way omap_gpio_irq_type() is handling it. Note that the long term solution is to change the gpio-omap driver to handle the banks as separate driver instances. This will allow us to rely on just runtime PM for tracking the bank specific state. Reported-by: Russell King Cc: Javier Martinez Canillas Cc: Kevin Hilman Cc: Santosh Shilimkar Tested-by: Felipe Balbi Signed-off-by: Tony Lindgren Signed-off-by: Linus Walleij --- drivers/gpio/gpio-omap.c | 39 +++++++++++++++++++++++++++++++++------ 1 file changed, 33 insertions(+), 6 deletions(-) diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c index 30646cfe0efa..f476ae2eb0b3 100644 --- a/drivers/gpio/gpio-omap.c +++ b/drivers/gpio/gpio-omap.c @@ -88,6 +88,8 @@ struct gpio_bank { #define BANK_USED(bank) (bank->mod_usage || bank->irq_usage) #define LINE_USED(line, offset) (line & (BIT(offset))) +static void omap_gpio_unmask_irq(struct irq_data *d); + static int omap_irq_to_gpio(struct gpio_bank *bank, unsigned int gpio_irq) { return bank->chip.base + gpio_irq; @@ -477,6 +479,16 @@ static int omap_gpio_is_input(struct gpio_bank *bank, int mask) return readl_relaxed(reg) & mask; } +static void omap_gpio_init_irq(struct gpio_bank *bank, unsigned gpio, + unsigned offset) +{ + if (!LINE_USED(bank->mod_usage, offset)) { + omap_enable_gpio_module(bank, offset); + omap_set_gpio_direction(bank, offset, 1); + } + bank->irq_usage |= BIT(GPIO_INDEX(bank, gpio)); +} + static int omap_gpio_irq_type(struct irq_data *d, unsigned type) { struct gpio_bank *bank = omap_irq_data_get_bank(d); @@ -506,15 +518,11 @@ static int omap_gpio_irq_type(struct irq_data *d, unsigned type) spin_lock_irqsave(&bank->lock, flags); offset = GPIO_INDEX(bank, gpio); retval = omap_set_gpio_triggering(bank, offset, type); - if (!LINE_USED(bank->mod_usage, offset)) { - omap_enable_gpio_module(bank, offset); - omap_set_gpio_direction(bank, offset, 1); - } else if (!omap_gpio_is_input(bank, BIT(offset))) { + omap_gpio_init_irq(bank, gpio, offset); + if (!omap_gpio_is_input(bank, BIT(offset))) { spin_unlock_irqrestore(&bank->lock, flags); return -EINVAL; } - - bank->irq_usage |= BIT(GPIO_INDEX(bank, gpio)); spin_unlock_irqrestore(&bank->lock, flags); if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH)) @@ -792,6 +800,24 @@ exit: pm_runtime_put(bank->dev); } +static unsigned int omap_gpio_irq_startup(struct irq_data *d) +{ + struct gpio_bank *bank = omap_irq_data_get_bank(d); + unsigned int gpio = omap_irq_to_gpio(bank, d->hwirq); + unsigned long flags; + unsigned offset = GPIO_INDEX(bank, gpio); + + if (!BANK_USED(bank)) + pm_runtime_get_sync(bank->dev); + + spin_lock_irqsave(&bank->lock, flags); + omap_gpio_init_irq(bank, gpio, offset); + spin_unlock_irqrestore(&bank->lock, flags); + omap_gpio_unmask_irq(d); + + return 0; +} + static void omap_gpio_irq_shutdown(struct irq_data *d) { struct gpio_bank *bank = omap_irq_data_get_bank(d); @@ -1181,6 +1207,7 @@ static int omap_gpio_probe(struct platform_device *pdev) if (!irqc) return -ENOMEM; + irqc->irq_startup = omap_gpio_irq_startup, irqc->irq_shutdown = omap_gpio_irq_shutdown, irqc->irq_ack = omap_gpio_ack_irq, irqc->irq_mask = omap_gpio_mask_irq, -- 2.20.1