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phy: qcom-usb-hs: Fix extcon double register after power cycle 

[ Upstream commit 64f86b9978 ]

Commit f0b5c2c963 ("phy: qcom-usb-hs: Replace the extcon API")
switched from extcon_register_notifier() to the resource-managed
API, i.e. devm_extcon_register_notifier().

This is problematic in this case, because the extcon notifier
is dynamically registered/unregistered whenever the PHY is powered
on/off. The resource-managed API does not unregister the notifier
until the driver is removed, so as soon as the PHY is power cycled,
attempting to register the notifier again results in:

	double register detected
	WARNING: CPU: 1 PID: 182 at kernel/notifier.c:26 notifier_chain_register+0x74/0xa0
	Call trace:
	 ...
	 extcon_register_notifier+0x74/0xb8
	 devm_extcon_register_notifier+0x54/0xb8
	 qcom_usb_hs_phy_power_on+0x1fc/0x208
	 ...

... and USB stops working after plugging the cable out and in
another time.

The easiest way to fix this is to make a partial revert of
commit f0b5c2c963 ("phy: qcom-usb-hs: Replace the extcon API")
and avoid using the resource-managed API in this case.

Fixes: f0b5c2c963 ("phy: qcom-usb-hs: Replace the extcon API")
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5.4-rM2-2.2.x-imx-squashed
Stephan Gerhold 2019-10-08 13:52:08 +02:00 committed by Greg Kroah-Hartman
parent f915c462bb
commit 8d42643c6c
1 changed files with 5 additions and 2 deletions
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7
drivers/phy/qualcomm/phy-qcom-usb-hs.c
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@ -158,8 +158,8 @@ static int qcom_usb_hs_phy_power_on(struct phy *phy)
/* setup initial state */
qcom_usb_hs_phy_vbus_notifier(&uphy->vbus_notify, state,
uphy->vbus_edev);
ret = devm_extcon_register_notifier(&ulpi->dev, uphy->vbus_edev,
EXTCON_USB, &uphy->vbus_notify);
ret = extcon_register_notifier(uphy->vbus_edev, EXTCON_USB,
&uphy->vbus_notify);
if (ret)
goto err_ulpi;
}
@ -180,6 +180,9 @@ static int qcom_usb_hs_phy_power_off(struct phy *phy)
{
struct qcom_usb_hs_phy *uphy = phy_get_drvdata(phy);
if (uphy->vbus_edev)
extcon_unregister_notifier(uphy->vbus_edev, EXTCON_USB,
&uphy->vbus_notify);
regulator_disable(uphy->v3p3);
regulator_disable(uphy->v1p8);
clk_disable_unprepare(uphy->sleep_clk);