diff options
Diffstat (limited to 'drivers/gpio/gpiolib.c')
| -rw-r--r-- | drivers/gpio/gpiolib.c | 24 |
1 files changed, 21 insertions, 3 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index ca1cb2d756c2..c3768fafff45 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -752,6 +752,7 @@ static struct class gpio_class = { */ static int gpiod_export(struct gpio_desc *desc, bool direction_may_change) { + struct gpio_chip *chip; unsigned long flags; int status; const char *ioname = NULL; @@ -769,8 +770,16 @@ static int gpiod_export(struct gpio_desc *desc, bool direction_may_change) return -EINVAL; } + chip = desc->chip; + mutex_lock(&sysfs_lock); + /* check if chip is being removed */ + if (!chip || !chip->exported) { + status = -ENODEV; + goto fail_unlock; + } + spin_lock_irqsave(&gpio_lock, flags); if (!test_bit(FLAG_REQUESTED, &desc->flags) || test_bit(FLAG_EXPORT, &desc->flags)) { @@ -1040,6 +1049,8 @@ static void gpiochip_unexport(struct gpio_chip *chip) { int status; struct device *dev; + struct gpio_desc *desc; + unsigned int i; mutex_lock(&sysfs_lock); dev = class_find_device(&gpio_class, NULL, chip, match_export); @@ -1047,6 +1058,7 @@ static void gpiochip_unexport(struct gpio_chip *chip) sysfs_remove_group(&dev->kobj, &gpiochip_attr_group); put_device(dev); device_unregister(dev); + /* prevent further gpiod exports */ chip->exported = 0; status = 0; } else @@ -1056,6 +1068,13 @@ static void gpiochip_unexport(struct gpio_chip *chip) if (status) pr_debug("%s: chip %s status %d\n", __func__, chip->label, status); + + /* unregister gpiod class devices owned by sysfs */ + for (i = 0; i < chip->ngpio; i++) { + desc = &chip->desc[i]; + if (test_and_clear_bit(FLAG_SYSFS, &desc->flags)) + gpiod_free(desc); + } } static int __init gpiolib_sysfs_init(void) @@ -1265,6 +1284,8 @@ int gpiochip_remove(struct gpio_chip *chip) int status = 0; unsigned id; + gpiochip_unexport(chip); + spin_lock_irqsave(&gpio_lock, flags); gpiochip_remove_pin_ranges(chip); @@ -1285,9 +1306,6 @@ int gpiochip_remove(struct gpio_chip *chip) spin_unlock_irqrestore(&gpio_lock, flags); - if (status == 0) - gpiochip_unexport(chip); - return status; } EXPORT_SYMBOL_GPL(gpiochip_remove); |