diff options
| -rw-r--r-- | drivers/pinctrl/bcm/pinctrl-bcm2835.c | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/drivers/pinctrl/bcm/pinctrl-bcm2835.c b/drivers/pinctrl/bcm/pinctrl-bcm2835.c index c7cdccdb4332..0f1ab0829ffe 100644 --- a/drivers/pinctrl/bcm/pinctrl-bcm2835.c +++ b/drivers/pinctrl/bcm/pinctrl-bcm2835.c @@ -90,6 +90,8 @@ struct bcm2835_pinctrl { struct pinctrl_gpio_range gpio_range; raw_spinlock_t irq_lock[BCM2835_NUM_BANKS]; + /* Protect FSEL registers */ + spinlock_t fsel_lock; }; /* pins are just named GPIO0..GPIO53 */ @@ -284,14 +286,19 @@ static inline void bcm2835_pinctrl_fsel_set( struct bcm2835_pinctrl *pc, unsigned pin, enum bcm2835_fsel fsel) { - u32 val = bcm2835_gpio_rd(pc, FSEL_REG(pin)); - enum bcm2835_fsel cur = (val >> FSEL_SHIFT(pin)) & BCM2835_FSEL_MASK; + u32 val; + enum bcm2835_fsel cur; + unsigned long flags; + + spin_lock_irqsave(&pc->fsel_lock, flags); + val = bcm2835_gpio_rd(pc, FSEL_REG(pin)); + cur = (val >> FSEL_SHIFT(pin)) & BCM2835_FSEL_MASK; dev_dbg(pc->dev, "read %08x (%u => %s)\n", val, pin, - bcm2835_functions[cur]); + bcm2835_functions[cur]); if (cur == fsel) - return; + goto unlock; if (cur != BCM2835_FSEL_GPIO_IN && fsel != BCM2835_FSEL_GPIO_IN) { /* always transition through GPIO_IN */ @@ -309,6 +316,9 @@ static inline void bcm2835_pinctrl_fsel_set( dev_dbg(pc->dev, "write %08x (%u <= %s)\n", val, pin, bcm2835_functions[fsel]); bcm2835_gpio_wr(pc, FSEL_REG(pin), val); + +unlock: + spin_unlock_irqrestore(&pc->fsel_lock, flags); } static int bcm2835_gpio_direction_input(struct gpio_chip *chip, unsigned offset) @@ -1248,6 +1258,7 @@ static int bcm2835_pinctrl_probe(struct platform_device *pdev) pc->gpio_chip = *pdata->gpio_chip; pc->gpio_chip.parent = dev; + spin_lock_init(&pc->fsel_lock); for (i = 0; i < BCM2835_NUM_BANKS; i++) { unsigned long events; unsigned offset; |