Re: [PATCH 2/2] usb: musb: sunxi: Unregister the extcon notifier in sunxi_musb_exit()

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential
issue to consider:
- [Medium] usb: musb: sunxi: missing cancel_work_sync() in
  sunxi_musb_init()
--

commit b343ab879ad454784f848e3901439d97d89167a9
Author: Rajan Yadav <rajanyadav0307@gmail.com>

usb: musb: sunxi: Unregister the extcon notifier in sunxi_musb_exit()

This commit switches sunxi_musb_init() from devm_extcon_register_notifier()
to extcon_register_notifier() and unregisters the notifier in
sunxi_musb_exit() and on the sunxi_musb_init() error path.

> diff --git a/drivers/usb/musb/sunxi.c b/drivers/usb/musb/sunxi.c
> index d880c3758c91b..e9107ae9d3417 100644
> --- a/drivers/usb/musb/sunxi.c
> +++ b/drivers/usb/musb/sunxi.c
> @@ -246,15 +246,19 @@ static int sunxi_musb_init(struct musb *musb)
>  
>  	writeb(SUNXI_MUSB_VEND0_PIO_MODE, musb->mregs + SUNXI_MUSB_VEND0);
>  
> -	/* Register notifier before calling phy_init() */
> -	ret = devm_extcon_register_notifier(glue->dev, glue->extcon,
> -					EXTCON_USB_HOST, &glue->host_nb);
> +	/*
> +	 * Register notifier before calling phy_init(). It is unregistered in
> +	 * sunxi_musb_exit(), as this runs again each time the musb-hdrc child
> +	 * is bound.
> +	 */
> +	ret = extcon_register_notifier(glue->extcon, EXTCON_USB_HOST,
> +				       &glue->host_nb);
>  	if (ret)
>  		goto error_reset_assert;
>  
>  	ret = phy_init(glue->phy);
>  	if (ret)
> -		goto error_reset_assert;
> +		goto error_unregister_notifier;
>  
>  	musb->isr = sunxi_musb_interrupt;
>  
> @@ -263,6 +267,9 @@ static int sunxi_musb_init(struct musb *musb)
>  
>  	return 0;
>  
> +error_unregister_notifier:
> +	extcon_unregister_notifier(glue->extcon, EXTCON_USB_HOST,
> +				   &glue->host_nb);
>  error_reset_assert:
>  	if (test_bit(SUNXI_MUSB_FL_HAS_RESET, &glue->flags))
>  		reset_control_assert(glue->rst);

[Severity: Medium]
Should the error_unregister_notifier path also call
cancel_work_sync(&glue->work) after extcon_unregister_notifier(), just like
sunxi_musb_exit() does?

An EXTCON_USB_HOST event arriving between extcon_register_notifier() and a
failing phy_init() schedules glue->work via sunxi_musb_host_notifier().
Because musb-hdrc fails to bind, unbinding the glue device in
sunxi_musb_remove() will not run sunxi_musb_exit() and devres can free
glue while glue->work is still queued or running.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261110-musb-sunxi-unbind-v1-0-d821584fc4a4@gmail.com?part=2