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Commit 3d746d25 authored by Manu Gautam's avatar Manu Gautam
Browse files

usb: f_serial: Add function suspend/resume for super-speed wakeup 



USB super-speed mode requires device to advertise remote wakeup
capability at function driver level called as function
wakeup capability. Host queries this using get_status and
uses set_feature to enable function remote wakeup before
initiating function suspend. This is required to initiate
remote wakeup as well which is failed by udc otherwise in SS mode.

CRs-Fixed: 964728
Change-Id: I6bb87b334ca1a5363c9d8e607c7a3d07deab04f2
Signed-off-by: default avatarManu Gautam <mgautam@codeaurora.org>
parent 747b0f6a

drivers/usb/gadget/function/f_serial.c

+45 −1
Original line number Diff line number Diff line
@@ -4,7 +4,7 @@ 
 * Copyright (C) 2003 Al Borchers (alborchers@steinerpoint.com)

 * Copyright (C) 2008 by David Brownell

 * Copyright (C) 2008 by Nokia Corporation

 * Copyright (c) 2014-2015, The Linux Foundation. All rights reserved.

 * Copyright (c) 2014-2016, The Linux Foundation. All rights reserved.

 *

 * This software is distributed under the terms of the GNU General

 * Public License ("GPL") as published by the Free Software Foundation,
@@ -643,6 +643,7 @@ static void gser_suspend(struct usb_function *f) 
static void gser_resume(struct usb_function *f)

{

	struct f_gser	*gser = func_to_gser(f);

	struct usb_composite_dev *cdev = gser->port.func.config->cdev;

	unsigned port_num;



	port_num = gserial_ports[gser->port_num].client_port_num;
@@ -650,6 +651,13 @@ static void gser_resume(struct usb_function *f) 
	pr_debug("%s: transport: %s f_gser: %p gserial: %p port_num: %d\n",

			__func__, xport_to_str(gser->transport),

			gser, &gser->port, gser->port_num);

	/*

	 * If the function is in USB3 Function Suspend state, resume is

	 * canceled. In this case resume is done by a Function Resume request.

	 */

	if ((cdev->gadget->speed == USB_SPEED_SUPER) &&

		f->func_is_suspended)

		return;



	switch (gser->transport) {

	case USB_GADGET_XPORT_SMD:
@@ -661,6 +669,40 @@ static void gser_resume(struct usb_function *f) 
	}

}



static int gser_func_suspend(struct usb_function *f, u8 options)

{

	bool func_wakeup_allowed;



	pr_debug("func susp %u cmd for %s", options, f->name ? f->name : "");



	func_wakeup_allowed =

		((options & FUNC_SUSPEND_OPT_RW_EN_MASK) != 0);



	if (options & FUNC_SUSPEND_OPT_SUSP_MASK) {

		f->func_wakeup_allowed = func_wakeup_allowed;

		if (!f->func_is_suspended) {

			gser_suspend(f);

			f->func_is_suspended = true;

		}

	} else {

		if (f->func_is_suspended) {

			f->func_is_suspended = false;

			gser_resume(f);

		}

		f->func_wakeup_allowed = func_wakeup_allowed;

	}



	return 0;

}



static int gser_get_status(struct usb_function *f)

{

	unsigned remote_wakeup_en_status = f->func_wakeup_allowed ? 1 : 0;



	return (remote_wakeup_en_status << FUNC_WAKEUP_ENABLE_SHIFT) |

		(1 << FUNC_WAKEUP_CAPABLE_SHIFT);

}



static int gser_notify(struct f_gser *gser, u8 type, u16 value,

		void *data, unsigned length)

{
@@ -1100,6 +1142,8 @@ static struct usb_function *gser_alloc(struct usb_function_instance *fi) 
	gser->port.func.setup = gser_setup;

	gser->port.func.suspend = gser_suspend;

	gser->port.func.resume = gser_resume;

	gser->port.func.func_suspend = gser_func_suspend;

	gser->port.func.get_status = gser_get_status;

	gser->port.connect = gser_connect;

	gser->port.get_dtr = gser_get_dtr;

	gser->port.get_rts = gser_get_rts;

drivers/usb/gadget/function/u_smd.c

+11 −6
Original line number Diff line number Diff line 
/*

 * u_smd.c - utilities for USB gadget serial over smd

 *

 * Copyright (c) 2011, 2013-2015, The Linux Foundation. All rights reserved.

 * Copyright (c) 2011, 2013-2016, The Linux Foundation. All rights reserved.

 *

 * This code also borrows from drivers/usb/gadget/u_serial.c, which is

 * Copyright (C) 2000 - 2003 Al Borchers (alborchers@steinerpoint.com)
@@ -322,13 +322,18 @@ static void gsmd_tx_pull(struct work_struct *w) 
	gadget = func->config->cdev->gadget;

	if (port->is_suspended) {

		spin_unlock_irq(&port->port_lock);

		if ((gadget->speed == USB_SPEED_SUPER) &&

		    (func->func_is_suspended))

			ret = usb_func_wakeup(func);

		else

			ret = usb_gadget_wakeup(gadget);

		spin_lock_irq(&port->port_lock);



		if (ret)

			pr_err("Failed to wake up the USB core. ret=%d.\n",

				ret);

		if ((ret == -EBUSY) || (ret == -EAGAIN))

			pr_debug("Remote wakeup is delayed due to LPM exit\n");

		else if (ret)

			pr_err("Failed to wake up the USB core. ret=%d\n", ret);



		spin_lock_irq(&port->port_lock);

		if (!port->port_usb) {

			pr_debug("%s: USB disconnected\n", __func__);

			spin_unlock_irq(&port->port_lock);

include/linux/usb/composite.h

+3 −0
Original line number Diff line number Diff line
@@ -45,6 +45,9 @@ 
#define FUNC_SUSPEND_OPT_SUSP_MASK BIT(0)

#define FUNC_SUSPEND_OPT_RW_EN_MASK BIT(1)



#define FUNC_WAKEUP_CAPABLE_SHIFT  0

#define FUNC_WAKEUP_ENABLE_SHIFT   1



/*

 * USB function drivers should return USB_GADGET_DELAYED_STATUS if they

 * wish to delay the data/status stages of the control transfer till they