diff options
| author | Axel Lin <axel.lin@gmail.com> | 2012-07-29 10:55:54 +0800 |
|---|---|---|
| committer | Linus Walleij <linus.walleij@linaro.org> | 2012-08-17 07:35:42 +0200 |
| commit | 7cb6580c0b2690e5c6ac1acd9375fa55d72af289 (patch) | |
| tree | ef8cb15817321278bc2111c771a3c99560d6a685 | |
| parent | 02a6794d57ce54b96b13db80831f35d66e0caf31 (diff) | |
| download | linux-rt-7cb6580c0b2690e5c6ac1acd9375fa55d72af289.tar.gz | |
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>
| -rw-r--r-- | drivers/gpio/gpio-pch.c | 22 |
1 files changed, 10 insertions, 12 deletions
diff --git a/drivers/gpio/gpio-pch.c b/drivers/gpio/gpio-pch.c index 139ad3e20011..4ad0c4f9171c 100644 --- a/drivers/gpio/gpio-pch.c +++ b/drivers/gpio/gpio-pch.c @@ -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); |