From 6a399547242df3b12f13d637a95f63eaa82f9385 Mon Sep 17 00:00:00 2001 From: Ben Dooks Date: Wed, 19 May 2010 16:31:49 +0900 Subject: ARM: S5P6440: Add locking to GPIO calls Add the new locking calls to ensure that these are always exclusively accessing the GPIO registers. Fixes a possible race between two threads modifying the same GPIO bank, Signed-off-by: Ben Dooks --- arch/arm/mach-s5p6440/gpio.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/arch/arm/mach-s5p6440/gpio.c b/arch/arm/mach-s5p6440/gpio.c index 262dc75d5be..92efc05b1ba 100644 --- a/arch/arm/mach-s5p6440/gpio.c +++ b/arch/arm/mach-s5p6440/gpio.c @@ -46,6 +46,7 @@ static int s5p6440_gpiolib_rbank_4bit2_input(struct gpio_chip *chip, void __iomem *base = ourchip->base; void __iomem *regcon = base; unsigned long con; + unsigned long flags; switch (offset) { case 6: @@ -63,10 +64,14 @@ static int s5p6440_gpiolib_rbank_4bit2_input(struct gpio_chip *chip, break; } + s3c_gpio_lock(ourchip, flags); + con = __raw_readl(regcon); con &= ~(0xf << con_4bit_shift(offset)); __raw_writel(con, regcon); + s3c_gpio_unlock(ourchip, flags); + return 0; } @@ -78,6 +83,7 @@ static int s5p6440_gpiolib_rbank_4bit2_output(struct gpio_chip *chip, void __iomem *regcon = base; unsigned long con; unsigned long dat; + unsigned long flags; unsigned con_offset = offset; switch (con_offset) { @@ -96,6 +102,8 @@ static int s5p6440_gpiolib_rbank_4bit2_output(struct gpio_chip *chip, break; } + s3c_gpio_lock(ourchip, flags); + con = __raw_readl(regcon); con &= ~(0xf << con_4bit_shift(con_offset)); con |= 0x1 << con_4bit_shift(con_offset); @@ -109,6 +117,8 @@ static int s5p6440_gpiolib_rbank_4bit2_output(struct gpio_chip *chip, __raw_writel(con, regcon); __raw_writel(dat, base + GPIODAT_OFF); + s3c_gpio_unlock(ourchip, flags); + return 0; } @@ -117,6 +127,7 @@ int s5p6440_gpio_setcfg_4bit_rbank(struct s3c_gpio_chip *chip, { void __iomem *reg = chip->base; unsigned int shift; + unsigned long flags; u32 con; switch (off) { @@ -142,11 +153,15 @@ int s5p6440_gpio_setcfg_4bit_rbank(struct s3c_gpio_chip *chip, cfg <<= shift; } + s3c_gpio_lock(chip, flags); + con = __raw_readl(reg); con &= ~(0xf << shift); con |= cfg; __raw_writel(con, reg); + s3c_gpio_unlock(chip, flags); + return 0; } -- cgit v1.2.3-70-g09d2