diff options
| author | Baruch Siach <baruch@tkos.co.il> | 2010-07-06 14:03:22 +0300 |
|---|---|---|
| committer | Sascha Hauer <s.hauer@pengutronix.de> | 2010-07-28 09:22:51 +0200 |
| commit | 14cb0deb66fcfca8fdbef75da8c84b5405a8c767 (patch) | |
| tree | 56f48e64c92f694c75a126a4bac0dee64d8f6b60 /arch/arm | |
| parent | ef93f1443c014e0d6dd7a5b1e592a02aa266f001 (diff) | |
| download | linux-14cb0deb66fcfca8fdbef75da8c84b5405a8c767.tar.bz2 | |
arm/imx/gpio: add spinlock protection
The GPIO registers need protection from concurrent access for operations that
are not atomic.
Cc: stable@kernel.org
Cc: Juergen Beisert <j.beisert@pengutronix.de>
Cc: Daniel Mack <daniel@caiaq.de>
Reported-by: rpkamiak@rockwellcollins.com
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'arch/arm')
| -rw-r--r-- | arch/arm/plat-mxc/gpio.c | 8 | ||||
| -rw-r--r-- | arch/arm/plat-mxc/include/mach/gpio.h | 1 |
2 files changed, 9 insertions, 0 deletions
diff --git a/arch/arm/plat-mxc/gpio.c b/arch/arm/plat-mxc/gpio.c index 11dc06190b5d..57ec4a896a5d 100644 --- a/arch/arm/plat-mxc/gpio.c +++ b/arch/arm/plat-mxc/gpio.c @@ -214,13 +214,16 @@ static void _set_gpio_direction(struct gpio_chip *chip, unsigned offset, struct mxc_gpio_port *port = container_of(chip, struct mxc_gpio_port, chip); u32 l; + unsigned long flags; + spin_lock_irqsave(&port->lock, flags); l = __raw_readl(port->base + GPIO_GDIR); if (dir) l |= 1 << offset; else l &= ~(1 << offset); __raw_writel(l, port->base + GPIO_GDIR); + spin_unlock_irqrestore(&port->lock, flags); } static void mxc_gpio_set(struct gpio_chip *chip, unsigned offset, int value) @@ -229,9 +232,12 @@ static void mxc_gpio_set(struct gpio_chip *chip, unsigned offset, int value) container_of(chip, struct mxc_gpio_port, chip); void __iomem *reg = port->base + GPIO_DR; u32 l; + unsigned long flags; + spin_lock_irqsave(&port->lock, flags); l = (__raw_readl(reg) & (~(1 << offset))) | (value << offset); __raw_writel(l, reg); + spin_unlock_irqrestore(&port->lock, flags); } static int mxc_gpio_get(struct gpio_chip *chip, unsigned offset) @@ -285,6 +291,8 @@ int __init mxc_gpio_init(struct mxc_gpio_port *port, int cnt) port[i].chip.base = i * 32; port[i].chip.ngpio = 32; + spin_lock_init(&port[i].lock); + /* its a serious configuration bug when it fails */ BUG_ON( gpiochip_add(&port[i].chip) < 0 ); diff --git a/arch/arm/plat-mxc/include/mach/gpio.h b/arch/arm/plat-mxc/include/mach/gpio.h index 9541ecbfd22c..661fbc605759 100644 --- a/arch/arm/plat-mxc/include/mach/gpio.h +++ b/arch/arm/plat-mxc/include/mach/gpio.h @@ -37,6 +37,7 @@ struct mxc_gpio_port { int virtual_irq_start; struct gpio_chip chip; u32 both_edges; + spinlock_t lock; }; int mxc_gpio_init(struct mxc_gpio_port*, int); |