diff mbox series

[02/14] power: reset: at91-reset:: Stop using module_platform_driver_probe()

Message ID 20231104211501.3676352-18-u.kleine-koenig@pengutronix.de (mailing list archive)
State Handled Elsewhere, archived
Headers show
Series power: reset: Drop platform_driver_probe() and convert to platform remove callback returning void | expand

Commit Message

Uwe Kleine-König Nov. 4, 2023, 9:15 p.m. UTC
On today's platforms the benefit of platform_driver_probe() isn't that
relevant any more. It allows to drop some code after booting (or module
loading) for .probe() and discard the .remove() function completely if
the driver is built-in. This typically saves a few 100k.

The downside of platform_driver_probe() is that the driver cannot be
bound and unbound at runtime which is ancient and so slightly
complicates testing. There are also thoughts to deprecate
platform_driver_probe() because it adds some complexity in the driver
core for little gain. Also many drivers don't use it correctly. This
driver for example misses to mark the driver struct with __ref which is
needed to suppress a (W=1) modpost warning.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
---
 drivers/power/reset/at91-reset.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

Comments

Claudiu Nov. 8, 2023, 6:54 a.m. UTC | #1
On 04.11.2023 23:15, Uwe Kleine-König wrote:
> On today's platforms the benefit of platform_driver_probe() isn't that
> relevant any more. It allows to drop some code after booting (or module
> loading) for .probe() and discard the .remove() function completely if
> the driver is built-in. This typically saves a few 100k.
> 
> The downside of platform_driver_probe() is that the driver cannot be
> bound and unbound at runtime which is ancient and so slightly
> complicates testing. There are also thoughts to deprecate
> platform_driver_probe() because it adds some complexity in the driver
> core for little gain. Also many drivers don't use it correctly. This
> driver for example misses to mark the driver struct with __ref which is
> needed to suppress a (W=1) modpost warning.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

Other than "::" in title:

Reviewed-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>

> ---
>  drivers/power/reset/at91-reset.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
> index aa9b012d3d00..af85f2f929ba 100644
> --- a/drivers/power/reset/at91-reset.c
> +++ b/drivers/power/reset/at91-reset.c
> @@ -337,7 +337,7 @@ static int at91_rcdev_init(struct at91_reset *reset,
>  	return devm_reset_controller_register(&pdev->dev, &reset->rcdev);
>  }
>  
> -static int __init at91_reset_probe(struct platform_device *pdev)
> +static int at91_reset_probe(struct platform_device *pdev)
>  {
>  	const struct of_device_id *match;
>  	struct at91_reset *reset;
> @@ -417,7 +417,7 @@ static int __init at91_reset_probe(struct platform_device *pdev)
>  	return ret;
>  }
>  
> -static int __exit at91_reset_remove(struct platform_device *pdev)
> +static int at91_reset_remove(struct platform_device *pdev)
>  {
>  	struct at91_reset *reset = platform_get_drvdata(pdev);
>  
> @@ -428,13 +428,14 @@ static int __exit at91_reset_remove(struct platform_device *pdev)
>  }
>  
>  static struct platform_driver at91_reset_driver = {
> -	.remove = __exit_p(at91_reset_remove),
> +	.probe = at91_reset_probe,
> +	.remove = at91_reset_remove,
>  	.driver = {
>  		.name = "at91-reset",
>  		.of_match_table = at91_reset_of_match,
>  	},
>  };
> -module_platform_driver_probe(at91_reset_driver, at91_reset_probe);
> +module_platform_driver(at91_reset_driver);
>  
>  MODULE_AUTHOR("Atmel Corporation");
>  MODULE_DESCRIPTION("Reset driver for Atmel SoCs");
diff mbox series

Patch

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index aa9b012d3d00..af85f2f929ba 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -337,7 +337,7 @@  static int at91_rcdev_init(struct at91_reset *reset,
 	return devm_reset_controller_register(&pdev->dev, &reset->rcdev);
 }
 
-static int __init at91_reset_probe(struct platform_device *pdev)
+static int at91_reset_probe(struct platform_device *pdev)
 {
 	const struct of_device_id *match;
 	struct at91_reset *reset;
@@ -417,7 +417,7 @@  static int __init at91_reset_probe(struct platform_device *pdev)
 	return ret;
 }
 
-static int __exit at91_reset_remove(struct platform_device *pdev)
+static int at91_reset_remove(struct platform_device *pdev)
 {
 	struct at91_reset *reset = platform_get_drvdata(pdev);
 
@@ -428,13 +428,14 @@  static int __exit at91_reset_remove(struct platform_device *pdev)
 }
 
 static struct platform_driver at91_reset_driver = {
-	.remove = __exit_p(at91_reset_remove),
+	.probe = at91_reset_probe,
+	.remove = at91_reset_remove,
 	.driver = {
 		.name = "at91-reset",
 		.of_match_table = at91_reset_of_match,
 	},
 };
-module_platform_driver_probe(at91_reset_driver, at91_reset_probe);
+module_platform_driver(at91_reset_driver);
 
 MODULE_AUTHOR("Atmel Corporation");
 MODULE_DESCRIPTION("Reset driver for Atmel SoCs");