Re: [PATCH v4 3/5] usb: gadget: Add function wakeup support

[Thinh Nguyen]

On Mon, Feb 13, 2023, Elson Roy Serrao wrote:
> A function which is in function suspend state has to send a
> function wake notification to the host in case it needs to
> exit from this state and resume data transfer. Add support to
> handle such requests by exposing a new gadget op.
> 
> Signed-off-by: Elson Roy Serrao <quic_eserrao@xxxxxxxxxxx>
> ---
>  drivers/usb/gadget/composite.c | 24 ++++++++++++++++++++++++
>  drivers/usb/gadget/udc/core.c  | 21 +++++++++++++++++++++
>  include/linux/usb/composite.h  |  6 ++++++
>  include/linux/usb/gadget.h     |  4 ++++
>  4 files changed, 55 insertions(+)
> 
> diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
> index a37a8f4..51d6ee9 100644
> --- a/drivers/usb/gadget/composite.c
> +++ b/drivers/usb/gadget/composite.c
> @@ -492,6 +492,30 @@ int usb_interface_id(struct usb_configuration *config,
>  }
>  EXPORT_SYMBOL_GPL(usb_interface_id);
>  
> +int usb_func_wakeup(struct usb_function *func)
> +{
> +	int ret, id;
> +
> +	if (!func->func_wakeup_armed) {
> +		ERROR(func->config->cdev, "not armed for func remote wakeup\n");
> +		return -EINVAL;
> +	}
> +
> +	for (id = 0; id < MAX_CONFIG_INTERFACES; id++)
> +		if (func->config->interface[id] == func)
> +			break;
> +
> +	if (id == MAX_CONFIG_INTERFACES) {
> +		ERROR(func->config->cdev, "Invalid function id:%d\n", id);

The print of id here is always MAX_CONFIG_INTERFACES right?

Thanks,
Thinh

> +		return -EINVAL;
> +	}
> +
> +	ret = usb_gadget_func_wakeup(func->config->cdev->gadget, id);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(usb_func_wakeup);
> +