Re: [PATCH RFC 2/5] drivers/soc/litex: Use devm_register_restart_handler()

["Gabriel L. Somlo" <gsomlo@xxxxxxxxx>]

On Fri, Nov 17, 2023 at 10:10:03AM -0600, Andrew Davis wrote:
> Use device life-cycle managed register function to simplify probe error
> path and eliminate need for explicit remove function.
> 
> Signed-off-by: Andrew Davis <afd@xxxxxx>

Reviewed-by: Gabriel Somlo <gsomlo@xxxxxxxxx>

Arnd: the original patch is available here for the purpose of pulling via
the soc tree:
https://lore.kernel.org/lkml/20231117161006.87734-3-afd@xxxxxx/

Thanks,
--Gabriel

> ---
>  drivers/soc/litex/litex_soc_ctrl.c | 23 +++++------------------
>  1 file changed, 5 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/soc/litex/litex_soc_ctrl.c b/drivers/soc/litex/litex_soc_ctrl.c
> index 10813299aa106..7a0096d93c73d 100644
> --- a/drivers/soc/litex/litex_soc_ctrl.c
> +++ b/drivers/soc/litex/litex_soc_ctrl.c
> @@ -69,14 +69,11 @@ static int litex_check_csr_access(void __iomem *reg_addr)
>  
>  struct litex_soc_ctrl_device {
>  	void __iomem *base;
> -	struct notifier_block reset_nb;
>  };
>  
> -static int litex_reset_handler(struct notifier_block *this, unsigned long mode,
> -			       void *cmd)
> +static int litex_reset_handler(struct sys_off_data *data)
>  {
> -	struct litex_soc_ctrl_device *soc_ctrl_dev =
> -		container_of(this, struct litex_soc_ctrl_device, reset_nb);
> +	struct litex_soc_ctrl_device *soc_ctrl_dev = data->cb_data;
>  
>  	litex_write32(soc_ctrl_dev->base + RESET_REG_OFF, RESET_REG_VALUE);
>  	return NOTIFY_DONE;
> @@ -107,11 +104,9 @@ static int litex_soc_ctrl_probe(struct platform_device *pdev)
>  	if (error)
>  		return error;
>  
> -	platform_set_drvdata(pdev, soc_ctrl_dev);
> -
> -	soc_ctrl_dev->reset_nb.notifier_call = litex_reset_handler;
> -	soc_ctrl_dev->reset_nb.priority = 128;
> -	error = register_restart_handler(&soc_ctrl_dev->reset_nb);
> +	error = devm_register_restart_handler(&pdev->dev,
> +					      litex_reset_handler,
> +					      soc_ctrl_dev);
>  	if (error) {
>  		dev_warn(&pdev->dev, "cannot register restart handler: %d\n",
>  			 error);
> @@ -120,20 +115,12 @@ static int litex_soc_ctrl_probe(struct platform_device *pdev)
>  	return 0;
>  }
>  
> -static void litex_soc_ctrl_remove(struct platform_device *pdev)
> -{
> -	struct litex_soc_ctrl_device *soc_ctrl_dev = platform_get_drvdata(pdev);
> -
> -	unregister_restart_handler(&soc_ctrl_dev->reset_nb);
> -}
> -
>  static struct platform_driver litex_soc_ctrl_driver = {
>  	.driver = {
>  		.name = "litex-soc-controller",
>  		.of_match_table = of_match_ptr(litex_soc_ctrl_of_match)
>  	},
>  	.probe = litex_soc_ctrl_probe,
> -	.remove_new = litex_soc_ctrl_remove,
>  };
>  
>  module_platform_driver(litex_soc_ctrl_driver);
> -- 
> 2.39.2
>