diff options
author | Tony Lindgren <tony@atomide.com> | 2015-01-17 01:50:50 +0300 |
---|---|---|
committer | Linus Walleij <linus.walleij@linaro.org> | 2015-01-26 11:10:44 +0300 |
commit | 3d009c8c61f96b50c068c8122e929352c359f877 (patch) | |
tree | 30fdee334f004c73fa720eeb6d0097d9aebfe0c2 /drivers/gpio/gpio-omap.c | |
parent | 26bc420b59a38e4e6685a73345a0def461136dce (diff) | |
download | linux-3d009c8c61f96b50c068c8122e929352c359f877.tar.xz |
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
...
[<c05f21e4>] (__irq_svc) from [<c05f1974>] (_raw_spin_unlock_irqrestore+0x34/0x44)
[<c05f1974>] (_raw_spin_unlock_irqrestore) from [<c00914a8>] (__setup_irq+0x244/0x530)
[<c00914a8>] (__setup_irq) from [<c00917d4>] (setup_irq+0x40/0x8c)
[<c00917d4>] (setup_irq) from [<c0039c8c>] (omap_system_dma_probe+0x1d4/0x2b4)
[<c0039c8c>] (omap_system_dma_probe) from [<c03b2200>] (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 <rmk+kernel@arm.linux.org.uk>
Cc: Javier Martinez Canillas <javier@dowhile0.org>
Cc: Kevin Hilman <khilman@kernel.org>
Cc: Santosh Shilimkar <ssantosh@kernel.org>
Tested-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/gpio/gpio-omap.c')
-rw-r--r-- | drivers/gpio/gpio-omap.c | 39 |
1 files 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, |