Re: [PATCH 1/5] platform/x86: msi-ec: Register a platform driver

["Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>]

On Tue, 10 Oct 2023, Nikita Kravets wrote:

> Register a platform driver for the future features.
> 
> Cc: Aakash Singh <mail@singhaakash.dev>
> Cc: Jose Angel Pastrana <japp0005@red.ujaen.es>
> Signed-off-by: Nikita Kravets <teackot@gmail.com>
> ---
>  drivers/platform/x86/msi-ec.c | 44 +++++++++++++++++++++++++++++++++++
>  1 file changed, 44 insertions(+)
> 
> diff --git a/drivers/platform/x86/msi-ec.c b/drivers/platform/x86/msi-ec.c
> index f26a3121092f..12c559c9eac4 100644
> --- a/drivers/platform/x86/msi-ec.c
> +++ b/drivers/platform/x86/msi-ec.c
> @@ -818,6 +818,30 @@ static struct acpi_battery_hook battery_hook = {
>  	.name = MSI_EC_DRIVER_NAME,
>  };
>  
> +/*
> + * Sysfs platform driver
> + */
> +
> +static int msi_platform_probe(struct platform_device *pdev)
> +{
> +	return 0;
> +}
> +
> +static int msi_platform_remove(struct platform_device *pdev)
> +{
> +	return 0;
> +}

No need to provide empty .probe() or .remove().

> +static struct platform_device *msi_platform_device;
> +
> +static struct platform_driver msi_platform_driver = {
> +	.driver = {
> +		.name = MSI_EC_DRIVER_NAME,
> +	},
> +	.probe = msi_platform_probe,
> +	.remove = msi_platform_remove,
> +};
> +
>  /*
>   * Module load/unload
>   */
> @@ -878,6 +902,23 @@ static int __init msi_ec_init(void)
>  	if (result < 0)
>  		return result;
>  
> +	result = platform_driver_register(&msi_platform_driver);
> +	if (result < 0)
> +		return result;
> +
> +	msi_platform_device = platform_device_alloc(MSI_EC_DRIVER_NAME, -1);
> +	if (msi_platform_device == NULL) {
> +		platform_driver_unregister(&msi_platform_driver);
> +		return -ENOMEM;
> +	}
> +
> +	result = platform_device_add(msi_platform_device);
> +	if (result < 0) {
> +		platform_device_del(msi_platform_device);
> +		platform_driver_unregister(&msi_platform_driver);
> +		return result;

Instead of duplicating error handling, make a proper rollback with goto 
and labels, or better yet, use the cleanup.h if you know how it works.

> +	}
> +
>  	battery_hook_register(&battery_hook);
>  	return 0;
>  }
> @@ -885,6 +926,9 @@ static int __init msi_ec_init(void)
>  static void __exit msi_ec_exit(void)
>  {
>  	battery_hook_unregister(&battery_hook);
> +
> +	platform_driver_unregister(&msi_platform_driver);
> +	platform_device_del(msi_platform_device);
>  }
>  
>  MODULE_LICENSE("GPL");
> 

-- 
 i.