diff options
Diffstat (limited to 'drivers/gpio/gpiolib.c')
-rw-r--r-- | drivers/gpio/gpiolib.c | 49 |
1 files changed, 46 insertions, 3 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index cae1b8c5b08c..3ca36542e338 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -722,7 +722,7 @@ int gpio_export(unsigned gpio, bool direction_may_change) unsigned long flags; struct gpio_desc *desc; int status = -EINVAL; - char *ioname = NULL; + const char *ioname = NULL; /* can't export until sysfs is available ... */ if (!gpio_class.p) { @@ -753,7 +753,7 @@ int gpio_export(unsigned gpio, bool direction_may_change) struct device *dev; dev = device_create(&gpio_class, desc->chip->dev, MKDEV(0, 0), - desc, ioname ? ioname : "gpio%d", gpio); + desc, ioname ? ioname : "gpio%u", gpio); if (!IS_ERR(dev)) { status = sysfs_create_group(&dev->kobj, &gpio_attr_group); @@ -1106,7 +1106,7 @@ unlock: fail: /* failures here can mean systems won't boot... */ if (status) - pr_err("gpiochip_add: gpios %d..%d (%s) not registered\n", + pr_err("gpiochip_add: gpios %d..%d (%s) failed to register\n", chip->base, chip->base + chip->ngpio - 1, chip->label ? : "generic"); return status; @@ -1447,6 +1447,49 @@ fail: } EXPORT_SYMBOL_GPL(gpio_direction_output); +/** + * gpio_set_debounce - sets @debounce time for a @gpio + * @gpio: the gpio to set debounce time + * @debounce: debounce time is microseconds + */ +int gpio_set_debounce(unsigned gpio, unsigned debounce) +{ + unsigned long flags; + struct gpio_chip *chip; + struct gpio_desc *desc = &gpio_desc[gpio]; + int status = -EINVAL; + + spin_lock_irqsave(&gpio_lock, flags); + + if (!gpio_is_valid(gpio)) + goto fail; + chip = desc->chip; + if (!chip || !chip->set || !chip->set_debounce) + goto fail; + gpio -= chip->base; + if (gpio >= chip->ngpio) + goto fail; + status = gpio_ensure_requested(desc, gpio); + if (status < 0) + goto fail; + + /* now we know the gpio is valid and chip won't vanish */ + + spin_unlock_irqrestore(&gpio_lock, flags); + + might_sleep_if(extra_checks && chip->can_sleep); + + return chip->set_debounce(chip, gpio, debounce); + +fail: + spin_unlock_irqrestore(&gpio_lock, flags); + if (status) + pr_debug("%s: gpio-%d status %d\n", + __func__, gpio, status); + + return status; +} +EXPORT_SYMBOL_GPL(gpio_set_debounce); /* I/O calls are only valid after configuration completed; the relevant * "is this a valid GPIO" error checks should already have been done. |