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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>
hifive-unleashed-5.1
Cyril Chemparathy 2010-05-01 18:37:55 -04:00 committed by Kevin Hilman
parent 686b634a07
commit b27b6d03f2
2 changed files with 8 additions and 4 deletions
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9
arch/arm/mach-davinci/gpio.c
View File

@ -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;

3
arch/arm/mach-davinci/include/mach/gpio.h
View File

@ -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;