From: Todd Poynor
usb: phy: Hold wakeupsource when USB is enumerated in peripheral mode
Purpose of this is to prevent the system to enter into suspend state from USB
peripheral traffic by hodling a wakeupsource when USB is connected and
enumerated in peripheral mode(say adb).
Disabled by default, can enable with:
echo Y > /sys/module/otg_wakeupsource/parameters/enabled
Cc: Felipe Balbi
Cc: Greg Kroah-Hartman
Cc: linux-kernel@vger.kernel.org
Cc: linux-...@vger.kernel.org
Cc: Android Kernel Team
Cc: John Stultz
Cc: Arve Hj�nnev�g
Cc: Benoit Goby
Signed-off-by: Todd Poynor
[kiran: Added context to commit message.
Included build fix from Benoit Goby and Arve Hj�nnev�g.
Removed lock->held field in driver as this mechanism is
provided in wakeupsource driver.
wakelock(wl) terminology replaced with wakeup_source(ws).
changed to "disabled by default" from "enable by default".
sys entry(module param) field modified to otg_wakeupsource.
included Todd's refactoring logic.
Introduced get_phy_hook to handle otgws_xceiv per-PHY.
otgws_nb moved to otg_wakeupsource_init function.
wakeupsource handling implemeted per-PHY(in phy core).
modified Kconfig help text]
Signed-off-by: Kiran Raparthy
---
drivers/usb/phy/Kconfig| 8 +++
drivers/usb/phy/Makefile | 1 +
drivers/usb/phy/otg-wakeupsource.c | 140 +
drivers/usb/phy/phy.c | 42 +++
include/linux/usb/phy.h| 8 +++
5 files changed, 199 insertions(+)
create mode 100644 drivers/usb/phy/otg-wakeupsource.c
diff --git a/drivers/usb/phy/Kconfig b/drivers/usb/phy/Kconfig
index e253fa0..d9ddd85 100644
--- a/drivers/usb/phy/Kconfig
+++ b/drivers/usb/phy/Kconfig
@@ -6,6 +6,14 @@ menu "USB Physical Layer drivers"
config USB_PHY
def_bool n
+config USB_OTG_WAKEUPSOURCE
+ bool "Hold wakeupsource when USB is enumerated in peripheral mode"
+ depends on PM_SLEEP
+ select USB_PHY
+ help
+ Prevent the system going into automatic suspend while
+ it is attached as a USB peripheral by holding a wakeupsource.
+
#
# USB Transceiver Drivers
#
diff --git a/drivers/usb/phy/Makefile b/drivers/usb/phy/Makefile
index 24a9133..ca2fbaf 100644
--- a/drivers/usb/phy/Makefile
+++ b/drivers/usb/phy/Makefile
@@ -3,6 +3,7 @@
#
obj-$(CONFIG_USB_PHY) += phy.o
obj-$(CONFIG_OF) += of.o
+obj-$(CONFIG_USB_OTG_WAKEUPSOURCE) += otg-wakeupsource.o
# transceiver drivers, keep the list sorted
diff --git a/drivers/usb/phy/otg-wakeupsource.c
b/drivers/usb/phy/otg-wakeupsource.c
new file mode 100644
index 000..fca2010
--- /dev/null
+++ b/drivers/usb/phy/otg-wakeupsource.c
@@ -0,0 +1,140 @@
+/*
+ * otg-wakeupsource.c
+ *
+ * Copyright (C) 2011 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+bool enabled = false;
+
+static DEFINE_SPINLOCK(otgws_spinlock);
+static struct usb_phy *get_phy_hook(void);
+
+static void otgws_handle_event(struct usb_phy *otgws_xceiv, unsigned long
event)
+{
+ unsigned long irqflags;
+
+ spin_lock_irqsave(&otgws_spinlock, irqflags);
+
+ if (!enabled) {
+ usb_drop_wsource(otgws_xceiv);
+ spin_unlock_irqrestore(&otgws_spinlock, irqflags);
+ return;
+ }
+
+ switch (event) {
+ case USB_EVENT_VBUS:
+ case USB_EVENT_ENUMERATED:
+ usb_grab_wsource(otgws_xceiv);
+ break;
+
+ case USB_EVENT_NONE:
+ case USB_EVENT_ID:
+ case USB_EVENT_CHARGER:
+ usb_drop_wsource(otgws_xceiv);
+ break;
+
+ default:
+ break;
+ }
+
+ spin_unlock_irqrestore(&otgws_spinlock, irqflags);
+}
+static struct usb_phy *get_phy_hook(void)
+{
+ struct usb_phy *phy;
+
+ phy = usb_get_phy(USB_PHY_TYPE_USB2);
+
+ if (IS_ERR(phy)) {
+ pr_err("%s: No OTG transceiver found\n", __func__);
+ return NULL;
+ }
+
+ return phy;
+}
+static int otgws_otg_notifications(struct notifier_block *nb,
+ unsigned long event, void *unused)
+{
+ static struct usb_phy *otgws_xceiv;
+
+ otgws_xceiv = get_phy_hook();
+
+ if (otgws_xceiv)
+ otgws_handle_event(otgws_xceiv, event);
+
+ return NOTIFY_OK;
+}
+
+static int set_enabled
