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gpio: gpio-pch: Use spinlock for register access protection 

gpio_chip.can_sleep is 0, but current code uses mutex in pch_gpio_set
pch_gpio_get and pch_gpio_direction_input functions.
Thus those functions are not callable from interrupt context.
This patch converts mutex into spinlock.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Axel Lin 2012-07-29 10:55:54 +08:00 committed by Linus Walleij
parent 02a6794d57
commit 7cb6580c0b
1 changed files with 10 additions and 12 deletions
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22
drivers/gpio/gpio-pch.c
View File

@ -92,9 +92,7 @@ struct pch_gpio_reg_data {
* @lock: Used for register access protection
* @irq_base: Save base of IRQ number for interrupt
* @ioh: IOH ID
* @spinlock: Used for register access protection in
* interrupt context pch_irq_mask,
* pch_irq_unmask and pch_irq_type;
* @spinlock: Used for register access protection
*/
struct pch_gpio {
void __iomem *base;
@ -102,7 +100,6 @@ struct pch_gpio {
struct device *dev;
struct gpio_chip gpio;
struct pch_gpio_reg_data pch_gpio_reg;
struct mutex lock;
int irq_base;
enum pch_type_t ioh;
spinlock_t spinlock;
@ -112,8 +109,9 @@ static void pch_gpio_set(struct gpio_chip *gpio, unsigned nr, int val)
{
u32 reg_val;
struct pch_gpio *chip = container_of(gpio, struct pch_gpio, gpio);
unsigned long flags;
mutex_lock(&chip->lock);
spin_lock_irqsave(&chip->spinlock, flags);
reg_val = ioread32(&chip->reg->po);
if (val)
reg_val |= (1 << nr);
@ -121,7 +119,7 @@ static void pch_gpio_set(struct gpio_chip *gpio, unsigned nr, int val)
reg_val &= ~(1 << nr);
iowrite32(reg_val, &chip->reg->po);
mutex_unlock(&chip->lock);
spin_unlock_irqrestore(&chip->spinlock, flags);
}
static int pch_gpio_get(struct gpio_chip *gpio, unsigned nr)
@ -137,8 +135,9 @@ static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
struct pch_gpio *chip = container_of(gpio, struct pch_gpio, gpio);
u32 pm;
u32 reg_val;
unsigned long flags;
mutex_lock(&chip->lock);
spin_lock_irqsave(&chip->spinlock, flags);
pm = ioread32(&chip->reg->pm) & ((1 << gpio_pins[chip->ioh]) - 1);
pm |= (1 << nr);
iowrite32(pm, &chip->reg->pm);
@ -149,8 +148,7 @@ static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
else
reg_val &= ~(1 << nr);
iowrite32(reg_val, &chip->reg->po);
mutex_unlock(&chip->lock);
spin_unlock_irqrestore(&chip->spinlock, flags);
return 0;
}
@ -159,12 +157,13 @@ static int pch_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
{
struct pch_gpio *chip = container_of(gpio, struct pch_gpio, gpio);
u32 pm;
unsigned long flags;
mutex_lock(&chip->lock);
spin_lock_irqsave(&chip->spinlock, flags);
pm = ioread32(&chip->reg->pm) & ((1 << gpio_pins[chip->ioh]) - 1);
pm &= ~(1 << nr);
iowrite32(pm, &chip->reg->pm);
mutex_unlock(&chip->lock);
spin_unlock_irqrestore(&chip->spinlock, flags);
return 0;
}
@ -387,7 +386,6 @@ static int __devinit pch_gpio_probe(struct pci_dev *pdev,
chip->reg = chip->base;
pci_set_drvdata(pdev, chip);
mutex_init(&chip->lock);
spin_lock_init(&chip->spinlock);
pch_gpio_setup(chip);
ret = gpiochip_add(&chip->gpio);