gpio: sysfs: clean up chip class-device handling
Clean gpio-chip class device registration and deregistration.
The class device is registered when a gpio-chip is added (or from
gpiolib_sysfs_init post-core init call), and deregistered when the chip
is removed.
Store the class device in struct gpio_chip directly rather than do a
class-device lookup on deregistration. This also removes the need for
the exported flag.
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index d19bf23..767b79a 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -582,7 +582,7 @@
mutex_lock(&sysfs_lock);
/* check if chip is being removed */
- if (!chip || !chip->exported) {
+ if (!chip || !chip->cdev) {
status = -ENODEV;
goto fail_unlock;
}
@@ -767,7 +767,6 @@
int gpiochip_export(struct gpio_chip *chip)
{
- int status;
struct device *dev;
/* Many systems register gpio chips for SOC support very early,
@@ -783,41 +782,29 @@
chip, gpiochip_groups,
"gpiochip%d", chip->base);
if (IS_ERR(dev))
- status = PTR_ERR(dev);
- else
- status = 0;
+ return PTR_ERR(dev);
mutex_lock(&sysfs_lock);
- chip->exported = (status == 0);
+ chip->cdev = dev;
mutex_unlock(&sysfs_lock);
- if (status)
- chip_dbg(chip, "%s: status %d\n", __func__, status);
-
- return status;
+ return 0;
}
void gpiochip_unexport(struct gpio_chip *chip)
{
- int status;
- struct device *dev;
struct gpio_desc *desc;
unsigned int i;
- dev = class_find_device(&gpio_class, NULL, chip, match_export);
- if (dev) {
- put_device(dev);
- device_unregister(dev);
- /* prevent further gpiod exports */
- mutex_lock(&sysfs_lock);
- chip->exported = false;
- mutex_unlock(&sysfs_lock);
- status = 0;
- } else
- status = -ENODEV;
+ if (!chip->cdev)
+ return;
- if (status)
- chip_dbg(chip, "%s: status %d\n", __func__, status);
+ device_unregister(chip->cdev);
+
+ /* prevent further gpiod exports */
+ mutex_lock(&sysfs_lock);
+ chip->cdev = NULL;
+ mutex_unlock(&sysfs_lock);
/* unregister gpiod class devices owned by sysfs */
for (i = 0; i < chip->ngpio; i++) {
@@ -845,7 +832,7 @@
*/
spin_lock_irqsave(&gpio_lock, flags);
list_for_each_entry(chip, &gpio_chips, list) {
- if (chip->exported)
+ if (chip->cdev)
continue;
/*