From 0edb555a65d1ef047a9805051c36922b52a38a9d Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= Date: Mon, 9 Oct 2023 12:37:26 +0200 Subject: [PATCH] platform: Make platform_driver::remove() return void MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit struct platform_driver::remove returning an integer made driver authors expect that returning an error code was proper error handling. However the driver core ignores the error and continues to remove the device because there is nothing the core could do anyhow and reentering the remove callback again is only calling for trouble. To prevent such wrong assumptions, change the return type of the remove callback to void. This was prepared by introducing an alternative remove callback returning void and converting all drivers to that. So .remove() can be changed without further changes in drivers. This corresponds to step b) of the plan outlined in commit 5c5a7680e67b ("platform: Provide a remove callback that returns no value"). Signed-off-by: Uwe Kleine-König --- drivers/base/platform.c | 10 ++-------- include/linux/platform_device.h | 15 +++++++-------- 2 files changed, 9 insertions(+), 16 deletions(-) diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 10c577963418..c8aa1be70526 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -1420,14 +1420,8 @@ static void platform_remove(struct device *_dev) struct platform_driver *drv = to_platform_driver(_dev->driver); struct platform_device *dev = to_platform_device(_dev); - if (drv->remove_new) { - drv->remove_new(dev); - } else if (drv->remove) { - int ret = drv->remove(dev); - - if (ret) - dev_warn(_dev, "remove callback returned a non-zero value. This will be ignored.\n"); - } + if (drv->remove) + drv->remove(dev); dev_pm_domain_detach(_dev, true); } diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index 7a41c72c1959..d422db6eec63 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -237,15 +237,14 @@ struct platform_driver { int (*probe)(struct platform_device *); /* - * Traditionally the remove callback returned an int which however is - * ignored by the driver core. This led to wrong expectations by driver - * authors who thought returning an error code was a valid error - * handling strategy. To convert to a callback returning void, new - * drivers should implement .remove_new() until the conversion it done - * that eventually makes .remove() return void. + * .remove_new() is a relic from a prototype conversion of .remove(). + * New drivers are supposed to implement .remove(). Once all drivers are + * converted to not use .remove_new any more, it will be dropped. */ - int (*remove)(struct platform_device *); - void (*remove_new)(struct platform_device *); + union { + void (*remove)(struct platform_device *); + void (*remove_new)(struct platform_device *); + }; void (*shutdown)(struct platform_device *); int (*suspend)(struct platform_device *, pm_message_t state);