diff options
| author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-03-31 12:33:13 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-03-31 18:44:54 +0300 |
| commit | 6f14c02220c791d5c46b0f965b9340c58f3d503d (patch) | |
| tree | 47548e187c398cc563fca7e15121e56b6e46c93d /drivers/gpio | |
| parent | 7d90e81a2d5edbd04037100bdd54d955bdd9b0d0 (diff) | |
| download | linux-6f14c02220c791d5c46b0f965b9340c58f3d503d.tar.xz | |
driver core: create class_is_registered()
Some classes (i.e. gpio), want to know if they have been registered or
not, and poke around in the class's internal structures to try to figure
this out. Because this is not really a good idea, provide a function
for classes to call to try to figure this out.
Note, this is racy as the state of the class could change at any moment
in time after the call is made, but as usually a class only wants to
know if it has been registered yet or not, it should be fairly safe to
use, and is just as safe as the previous "poke at the class internals"
check was.
Move the gpiolib code to use this function as proof that it works
properly.
Cc: Bartosz Golaszewski <brgl@bgdev.pl>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc: linux-gpio@vger.kernel.org
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
Link: https://lore.kernel.org/r/20230331093318.82288-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/gpiolib-sysfs.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c index a895915affa5..1a9b21731cc9 100644 --- a/drivers/gpio/gpiolib-sysfs.c +++ b/drivers/gpio/gpiolib-sysfs.c @@ -554,7 +554,7 @@ int gpiod_export(struct gpio_desc *desc, bool direction_may_change) int offset; /* can't export until sysfs is available ... */ - if (!gpio_class.p) { + if (!class_is_registered(&gpio_class)) { pr_debug("%s: called too early!\n", __func__); return -ENOENT; } @@ -728,7 +728,7 @@ int gpiochip_sysfs_register(struct gpio_device *gdev) * register later, in gpiolib_sysfs_init() ... here we just * verify that _some_ field of gpio_class got initialized. */ - if (!gpio_class.p) + if (!class_is_registered(&gpio_class)) return 0; /* |