summaryrefslogtreecommitdiffstats
path: root/arch
diff options
context:
space:
mode:
authorBen Dooks <ben-linux@fluff.org>2010-05-19 16:31:49 +0900
committerBen Dooks <ben-linux@fluff.org>2010-05-20 21:05:40 +0900
commit6a399547242df3b12f13d637a95f63eaa82f9385 (patch)
treeaf4ea12f9734f6020d0fd1219d2077ed80cbb20d /arch
parent1ae35de1c1ac81f8f31879316656b0a66616a4b0 (diff)
downloadop-kernel-dev-6a399547242df3b12f13d637a95f63eaa82f9385.zip
op-kernel-dev-6a399547242df3b12f13d637a95f63eaa82f9385.tar.gz
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 <ben-linux@fluff.org>
Diffstat (limited to 'arch')
-rw-r--r--arch/arm/mach-s5p6440/gpio.c15
1 files changed, 15 insertions, 0 deletions
diff --git a/arch/arm/mach-s5p6440/gpio.c b/arch/arm/mach-s5p6440/gpio.c
index 262dc75..92efc05 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;
}
OpenPOWER on IntegriCloud