cpm2: Fix race condition in CPM2 GPIO library.
The CPM2 GPIO library code uses the non thread-safe clrbits32/setbits32
macros. This patch protects them with a spinlock.
Signed-off-by: Laurent Pinchart <laurentp@cse-semaphore.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/arch/powerpc/sysdev/cpm_common.c b/arch/powerpc/sysdev/cpm_common.c
index 53da8a0..00d3d17 100644
--- a/arch/powerpc/sysdev/cpm_common.c
+++ b/arch/powerpc/sysdev/cpm_common.c
@@ -254,37 +254,48 @@
return !!(in_be32(&iop->dat) & pin_mask);
}
+static void __cpm2_gpio32_set(struct of_mm_gpio_chip *mm_gc, u32 pin_mask,
+ int value)
+{
+ struct cpm2_gpio32_chip *cpm2_gc = to_cpm2_gpio32_chip(mm_gc);
+ struct cpm2_ioports __iomem *iop = mm_gc->regs;
+
+ if (value)
+ cpm2_gc->cpdata |= pin_mask;
+ else
+ cpm2_gc->cpdata &= ~pin_mask;
+
+ out_be32(&iop->dat, cpm2_gc->cpdata);
+}
+
static void cpm2_gpio32_set(struct gpio_chip *gc, unsigned int gpio, int value)
{
struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
struct cpm2_gpio32_chip *cpm2_gc = to_cpm2_gpio32_chip(mm_gc);
+ unsigned long flags;
+ u32 pin_mask = 1 << (31 - gpio);
+
+ spin_lock_irqsave(&cpm2_gc->lock, flags);
+
+ __cpm2_gpio32_set(mm_gc, pin_mask, value);
+
+ spin_unlock_irqrestore(&cpm2_gc->lock, flags);
+}
+
+static int cpm2_gpio32_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
+{
+ struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+ struct cpm2_gpio32_chip *cpm2_gc = to_cpm2_gpio32_chip(mm_gc);
struct cpm2_ioports __iomem *iop = mm_gc->regs;
unsigned long flags;
u32 pin_mask = 1 << (31 - gpio);
spin_lock_irqsave(&cpm2_gc->lock, flags);
- if (value)
- cpm2_gc->cpdata |= pin_mask;
- else
- cpm2_gc->cpdata &= ~pin_mask;
-
- out_be32(&iop->dat, cpm2_gc->cpdata);
+ setbits32(&iop->dir, pin_mask);
+ __cpm2_gpio32_set(mm_gc, pin_mask, val);
spin_unlock_irqrestore(&cpm2_gc->lock, flags);
-}
-
-static int cpm2_gpio32_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
-{
- struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
- struct cpm2_ioports __iomem *iop = mm_gc->regs;
- u32 pin_mask;
-
- pin_mask = 1 << (31 - gpio);
-
- setbits32(&iop->dir, pin_mask);
-
- cpm2_gpio32_set(gc, gpio, val);
return 0;
}
@@ -292,13 +303,17 @@
static int cpm2_gpio32_dir_in(struct gpio_chip *gc, unsigned int gpio)
{
struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+ struct cpm2_gpio32_chip *cpm2_gc = to_cpm2_gpio32_chip(mm_gc);
struct cpm2_ioports __iomem *iop = mm_gc->regs;
- u32 pin_mask;
+ unsigned long flags;
+ u32 pin_mask = 1 << (31 - gpio);
- pin_mask = 1 << (31 - gpio);
+ spin_lock_irqsave(&cpm2_gc->lock, flags);
clrbits32(&iop->dir, pin_mask);
+ spin_unlock_irqrestore(&cpm2_gc->lock, flags);
+
return 0;
}