[PATCH] gpiolib: fix sysfs when cdev is not selected

From: Kent Gibson
Date: Thu Nov 05 2020 - 05:41:14 EST


In gpiochip_setup_dev() the call to gpiolib_cdev_register() indirectly
calls device_add(). This is still required for the sysfs even when
CONFIG_GPIO_CDEV is not selected in the build.

Replace the stubbed functions in gpiolib-cdev.h with macros in gpiolib.c
that perform the required device_add() and device_del() when
CONFIG_GPIO_CDEV is not selected.

Fixes: d143493c01b7 (gpiolib: make cdev a build option)
Reported-by: Nicolas Schichan <nschichan@xxxxxxxxxx>
Signed-off-by: Kent Gibson <warthog618@xxxxxxxxx>
---
drivers/gpio/gpiolib-cdev.h | 15 ---------------
drivers/gpio/gpiolib.c | 18 +++++++++++++++---
2 files changed, 15 insertions(+), 18 deletions(-)

diff --git a/drivers/gpio/gpiolib-cdev.h b/drivers/gpio/gpiolib-cdev.h
index cb41dd757338..b42644cbffb8 100644
--- a/drivers/gpio/gpiolib-cdev.h
+++ b/drivers/gpio/gpiolib-cdev.h
@@ -7,22 +7,7 @@

struct gpio_device;

-#ifdef CONFIG_GPIO_CDEV
-
int gpiolib_cdev_register(struct gpio_device *gdev, dev_t devt);
void gpiolib_cdev_unregister(struct gpio_device *gdev);

-#else
-
-static inline int gpiolib_cdev_register(struct gpio_device *gdev, dev_t devt)
-{
- return 0;
-}
-
-static inline void gpiolib_cdev_unregister(struct gpio_device *gdev)
-{
-}
-
-#endif /* CONFIG_GPIO_CDEV */
-
#endif /* GPIOLIB_CDEV_H */
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 8e29a60c3697..c980ddcda833 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -480,11 +480,23 @@ static void gpiodevice_release(struct device *dev)
kfree(gdev);
}

+#ifdef CONFIG_GPIO_CDEV
+#define gcdev_register(gdev, devt) gpiolib_cdev_register((gdev), (devt))
+#define gcdev_unregister(gdev) gpiolib_cdev_unregister((gdev))
+#else
+/*
+ * gpiolib_cdev_register() indirectly calls device_add(), which is still
+ * required even when cdev is not selected.
+ */
+#define gcdev_register(gdev, devt) device_add(&(gdev)->dev)
+#define gcdev_unregister(gdev) device_del(&(gdev)->dev)
+#endif
+
static int gpiochip_setup_dev(struct gpio_device *gdev)
{
int ret;

- ret = gpiolib_cdev_register(gdev, gpio_devt);
+ ret = gcdev_register(gdev, gpio_devt);
if (ret)
return ret;

@@ -500,7 +512,7 @@ static int gpiochip_setup_dev(struct gpio_device *gdev)
return 0;

err_remove_device:
- gpiolib_cdev_unregister(gdev);
+ gcdev_unregister(gdev);
return ret;
}

@@ -825,7 +837,7 @@ void gpiochip_remove(struct gpio_chip *gc)
* be removed, else it will be dangling until the last user is
* gone.
*/
- gpiolib_cdev_unregister(gdev);
+ gcdev_unregister(gdev);
put_device(&gdev->dev);
}
EXPORT_SYMBOL_GPL(gpiochip_remove);
--
2.29.2