[PATCH] gpio: don't warn about removing GPIO chips with active users anymore

From: Bartosz Golaszewski
Date: Wed Feb 21 2024 - 05:21:16 EST


From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>

With SRCU we can now correctly handle the situation when a GPIO provider
is removed while having users still holding references to GPIO
descriptors. Remove all warnings emitted in this situation.

Suggested-by: Kent Gibson <warthog618@xxxxxxxxx>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
---
drivers/gpio/gpiolib.c | 20 ++------------------
1 file changed, 2 insertions(+), 18 deletions(-)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 3c22920bd201..63e793a410e3 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1106,7 +1106,6 @@ EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
void gpiochip_remove(struct gpio_chip *gc)
{
struct gpio_device *gdev = gc->gpiodev;
- unsigned int i;

/* FIXME: should the legacy sysfs handling be moved to gpio_device? */
gpiochip_sysfs_unregister(gdev);
@@ -1130,15 +1129,6 @@ void gpiochip_remove(struct gpio_chip *gc)
*/
gpiochip_set_data(gc, NULL);

- for (i = 0; i < gdev->ngpio; i++) {
- if (test_bit(FLAG_REQUESTED, &gdev->descs[i].flags))
- break;
- }
-
- if (i != gdev->ngpio)
- dev_crit(&gdev->dev,
- "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
-
/*
* The gpiochip side puts its use of the device to rest here:
* if there are no userspace clients, the chardev and device will
@@ -2329,10 +2319,9 @@ int gpiod_request(struct gpio_desc *desc, const char *label)
return ret;
}

-static bool gpiod_free_commit(struct gpio_desc *desc)
+static void gpiod_free_commit(struct gpio_desc *desc)
{
unsigned long flags;
- bool ret = false;

might_sleep();

@@ -2357,23 +2346,18 @@ static bool gpiod_free_commit(struct gpio_desc *desc)
#ifdef CONFIG_OF_DYNAMIC
WRITE_ONCE(desc->hog, NULL);
#endif
- ret = true;
desc_set_label(desc, NULL);
WRITE_ONCE(desc->flags, flags);

gpiod_line_state_notify(desc, GPIOLINE_CHANGED_RELEASED);
}
-
- return ret;
}

void gpiod_free(struct gpio_desc *desc)
{
VALIDATE_DESC_VOID(desc);

- if (!gpiod_free_commit(desc))
- WARN_ON(1);
-
+ gpiod_free_commit(desc);
module_put(desc->gdev->owner);
gpio_device_put(desc->gdev);
}
--
2.40.1