Date:   Tue, 7 Feb 2023 06:56:20 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Elson Roy Serrao <quic_eserrao@quicinc.com>
Cc:     Thinh.Nguyen@synopsys.com, balbi@kernel.org,
        linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org,
        quic_wcheng@quicinc.com, quic_jackp@quicinc.com
Subject: Re: [PATCH v3 3/5] usb: gadget: Add function wakeup support
Message-ID: <Y+HoBPM6a64erF3z@kroah.com>
References: <1675710806-9735-1-git-send-email-quic_eserrao@quicinc.com>
 <1675710806-9735-4-git-send-email-quic_eserrao@quicinc.com>
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In-Reply-To: <1675710806-9735-4-git-send-email-quic_eserrao@quicinc.com>
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On Mon, Feb 06, 2023 at 11:13:24AM -0800, 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@quicinc.com>
> ---
>  drivers/usb/gadget/composite.c | 26 ++++++++++++++++++++++++++
>  drivers/usb/gadget/udc/core.c  | 19 +++++++++++++++++++
>  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 e459fb0..aa243d8 100644
> --- a/drivers/usb/gadget/composite.c
> +++ b/drivers/usb/gadget/composite.c
> @@ -492,6 +492,32 @@ 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_rw_armed) {
> +		ERROR(func->config->cdev, "func remote wakeup not enabled\n");
> +		return -EINVAL;
> +	}
> +
> +	DBG(func->config->cdev, "%s function wakeup\n", func->name);
> +
> +	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);
> +		return -EINVAL;
> +	}
> +
> +	ret = usb_gadget_func_wakeup(func->config->cdev->gadget, id);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL(usb_func_wakeup);

EXPORT_SYMBOL_GPL() please.

thanks,

greg k-h