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authorCyril Chemparathy <cyril@ti.com>2010-05-02 00:37:55 +0200
committerKevin Hilman <khilman@deeprootsystems.com>2010-05-07 00:02:09 +0200
commitb27b6d03f245e5eaf6473da58a2612077fb7cfe7 (patch)
treeb6ed359c8b604edcaed5025aa83c57d77daec1a9
parentDavinci: gpio - controller type support (diff)
downloadlinux-b27b6d03f245e5eaf6473da58a2612077fb7cfe7.tar.xz
linux-b27b6d03f245e5eaf6473da58a2612077fb7cfe7.zip
Davinci: gpio - fine grained locking
This patch eliminates the global gpio_lock, and implements a per-controller lock instead. This also switches to irqsave/irqrestore locks in case gpios are manipulated in isr. Signed-off-by: Cyril Chemparathy <cyril@ti.com> Tested-by: Sandeep Paulraj <s-paulraj@ti.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
-rw-r--r--arch/arm/mach-davinci/gpio.c9
-rw-r--r--arch/arm/mach-davinci/include/mach/gpio.h3
2 files changed, 8 insertions, 4 deletions
diff --git a/arch/arm/mach-davinci/gpio.c b/arch/arm/mach-davinci/gpio.c
index e422cd300d4c..b62d5e2bd37e 100644
--- a/arch/arm/mach-davinci/gpio.c
+++ b/arch/arm/mach-davinci/gpio.c
@@ -33,8 +33,6 @@ struct davinci_gpio_regs {
u32 intstat;
};
-static DEFINE_SPINLOCK(gpio_lock);
-
#define chip2controller(chip) \
container_of(chip, struct davinci_gpio_controller, chip)
@@ -83,10 +81,11 @@ static inline int __davinci_direction(struct gpio_chip *chip,
{
struct davinci_gpio_controller *d = chip2controller(chip);
struct davinci_gpio_regs __iomem *g = d->regs;
+ unsigned long flags;
u32 temp;
u32 mask = 1 << offset;
- spin_lock(&gpio_lock);
+ spin_lock_irqsave(&d->lock, flags);
temp = __raw_readl(&g->dir);
if (out) {
temp &= ~mask;
@@ -95,7 +94,7 @@ static inline int __davinci_direction(struct gpio_chip *chip,
temp |= mask;
}
__raw_writel(temp, &g->dir);
- spin_unlock(&gpio_lock);
+ spin_unlock_irqrestore(&d->lock, flags);
return 0;
}
@@ -175,6 +174,8 @@ static int __init davinci_gpio_setup(void)
if (chips[i].chip.ngpio > 32)
chips[i].chip.ngpio = 32;
+ spin_lock_init(&chips[i].lock);
+
regs = gpio2regs(base);
chips[i].regs = regs;
chips[i].set_data = &regs->set_data;
diff --git a/arch/arm/mach-davinci/include/mach/gpio.h b/arch/arm/mach-davinci/include/mach/gpio.h
index 9a71a26eb77f..504cc180a60b 100644
--- a/arch/arm/mach-davinci/include/mach/gpio.h
+++ b/arch/arm/mach-davinci/include/mach/gpio.h
@@ -14,6 +14,8 @@
#define __DAVINCI_GPIO_H
#include <linux/io.h>
+#include <linux/spinlock.h>
+
#include <asm-generic/gpio.h>
#include <mach/irqs.h>
@@ -52,6 +54,7 @@ enum davinci_gpio_type {
struct davinci_gpio_controller {
struct gpio_chip chip;
int irq_base;
+ spinlock_t lock;
void __iomem *regs;
void __iomem *set_data;
void __iomem *clr_data;