[PATCH 2/3] usb: gadget: f_acm: Allow restarting ACM console after stopping it

[Mattijs Korpershoek]

Hi Stephan,

Thank you for the patch.

On lun., avril 07, 2025 at 16:59, Stephan Gerhold <stephan.gerhold at linaro.org> wrote:

> When using IOMUX, the "usbacm" console can be added/removed dynamically
> from the stdout/stderr/stdin environment variables to allow temporarily
> starting other USB gadgets (e.g. Fastboot).
>
> However, right now acm_stdio_stop() does not completely undo
> acm_stdio_start(): The USB gadget is unregistered, but as long as dev->priv
> stays set acm_stdio_start() will never register the USB gadget again.
>
> Clear dev->priv after we detach to make sure a start operation after a stop
> operation registers the gadget again.
>
> Fixes: fc2b399ac03b ("usb: gadget: Add CDC ACM function")
> Signed-off-by: Stephan Gerhold <stephan.gerhold at linaro.org>

Reviewed-by: Mattijs Korpershoek <mkorpershoek at kernel.org>

> ---
>  drivers/usb/gadget/f_acm.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/usb/gadget/f_acm.c b/drivers/usb/gadget/f_acm.c
> index 2665fa4168f99b35a8c595aa24cb3fc4e8ab8529..8f7256069f58527b2e43e5add725a0b5f06baa6d 100644
> --- a/drivers/usb/gadget/f_acm.c
> +++ b/drivers/usb/gadget/f_acm.c
> @@ -663,6 +663,7 @@ static int acm_stdio_stop(struct stdio_dev *dev)
>  {
>  	g_dnl_unregister();
>  	g_dnl_clear_detach();
> +	dev->priv = NULL;
>  
>  	return 0;
>  }
>
> -- 
> 2.47.2