From d7a6c0ce8d26412903c7981503bad9e1cc7c45d2 Mon Sep 17 00:00:00 2001 From: Kai-Heng Feng Date: Sat, 12 Jan 2019 03:54:25 +0800 Subject: USB: Consolidate LPM checks to avoid enabling LPM twice MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit USB Bluetooth controller QCA ROME (0cf3:e007) sometimes stops working after S3: [ 165.110742] Bluetooth: hci0: using NVM file: qca/nvm_usb_00000302.bin [ 168.432065] Bluetooth: hci0: Failed to send body at 4 of 1953 (-110) After some experiments, I found that disabling LPM can workaround the issue. On some platforms, the USB power is cut during S3, so the driver uses reset-resume to resume the device. During port resume, LPM gets enabled twice, by usb_reset_and_verify_device() and usb_port_resume(). Consolidate all checks into new LPM helpers to make sure LPM only gets enabled once. Fixes: de68bab4fa96 ("usb: Don't enable USB 2.0 Link PM by default.”) Signed-off-by: Kai-Heng Feng Cc: stable # after much soaking Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/driver.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'drivers/usb/core/driver.c') diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index c276ffc5561f..8987cec9549d 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -1901,9 +1901,6 @@ static int usb_set_usb2_hardware_lpm(struct usb_device *udev, int enable) struct usb_hcd *hcd = bus_to_hcd(udev->bus); int ret = -EPERM; - if (enable && !udev->usb2_hw_lpm_allowed) - return 0; - if (hcd->driver->set_usb2_hw_lpm) { ret = hcd->driver->set_usb2_hw_lpm(hcd, udev, enable); if (!ret) @@ -1915,11 +1912,19 @@ static int usb_set_usb2_hardware_lpm(struct usb_device *udev, int enable) int usb_enable_usb2_hardware_lpm(struct usb_device *udev) { + if (!udev->usb2_hw_lpm_capable || + !udev->usb2_hw_lpm_allowed || + udev->usb2_hw_lpm_enabled) + return 0; + return usb_set_usb2_hardware_lpm(udev, 1); } int usb_disable_usb2_hardware_lpm(struct usb_device *udev) { + if (!udev->usb2_hw_lpm_enabled) + return 0; + return usb_set_usb2_hardware_lpm(udev, 0); } -- cgit v1.2.3