From 27375c513937c315c55340d9b35ed61942171630 Mon Sep 17 00:00:00 2001 From: Gabor Juhos Date: Tue, 13 Jul 2010 16:52:04 +0000 Subject: [PATCH] ramips: protect GPIO register access with a spinlock SVN-Revision: 22171 --- .../ramips/files/arch/mips/ralink/common/gpio.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/target/linux/ramips/files/arch/mips/ralink/common/gpio.c b/target/linux/ramips/files/arch/mips/ralink/common/gpio.c index 892f15b1ed..e350fc1736 100644 --- a/target/linux/ramips/files/arch/mips/ralink/common/gpio.c +++ b/target/linux/ramips/files/arch/mips/ralink/common/gpio.c @@ -10,7 +10,7 @@ #include #include - +#include #include #include @@ -64,6 +64,7 @@ enum ramips_pio_reg { struct ramips_gpio_chip { struct gpio_chip chip; + spinlock_t lock; u8 regs[RAMIPS_GPIO_REG_MAX]; }; @@ -90,11 +91,14 @@ static inline u32 ramips_gpio_rr(struct ramips_gpio_chip *rg, u8 reg) static int ramips_gpio_direction_input(struct gpio_chip *chip, unsigned offset) { struct ramips_gpio_chip *rg = to_ramips_gpio(chip); + unsigned long flags; u32 t; + spin_lock_irqsave(&rg->lock, flags); t = ramips_gpio_rr(rg, RAMIPS_GPIO_REG_DIR); t &= ~(1 << offset); ramips_gpio_wr(rg, RAMIPS_GPIO_REG_DIR, t); + spin_unlock_irqrestore(&rg->lock, flags); return 0; } @@ -103,15 +107,19 @@ static int ramips_gpio_direction_output(struct gpio_chip *chip, unsigned offset, int value) { struct ramips_gpio_chip *rg = to_ramips_gpio(chip); + unsigned long flags; u32 reg; u32 t; reg = (value) ? RAMIPS_GPIO_REG_SET : RAMIPS_GPIO_REG_RESET; + + spin_lock_irqsave(&rg->lock, flags); ramips_gpio_wr(rg, reg, 1 << offset); t = ramips_gpio_rr(rg, RAMIPS_GPIO_REG_DIR); t |= 1 << offset; ramips_gpio_wr(rg, RAMIPS_GPIO_REG_DIR, t); + spin_unlock_irqrestore(&rg->lock, flags); return 0; } @@ -208,6 +216,8 @@ static struct ramips_gpio_chip ramips_gpio_chip2 = { static __init void ramips_gpio_chip_add(struct ramips_gpio_chip *rg) { + spin_lock_init(&rg->lock); + /* set polarity to low for all lines */ ramips_gpio_wr(rg, RAMIPS_GPIO_REG_POL, 0);