From d7a6c0ce8d26412903c7981503bad9e1cc7c45d2 Mon Sep 17 00:00:00 2001 From: Kai-Heng Feng Date: Sat, 12 Jan 2019 03:54:25 +0800 Subject: [PATCH] USB: Consolidate LPM checks to avoid enabling LPM twice MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 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 ++++++++--- drivers/usb/core/hub.c | 12 ++++-------- drivers/usb/core/message.c | 3 +-- 3 files changed, 13 insertions(+), 13 deletions(-) diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index c276ffc..8987cec 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); } diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 7337e94..bb0830c 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -3251,8 +3251,7 @@ int usb_port_suspend(struct usb_device *udev, pm_message_t msg) } /* disable USB2 hardware LPM */ - if (udev->usb2_hw_lpm_enabled == 1) - usb_disable_usb2_hardware_lpm(udev); + usb_disable_usb2_hardware_lpm(udev); if (usb_disable_ltm(udev)) { dev_err(&udev->dev, "Failed to disable LTM before suspend\n"); @@ -3290,8 +3289,7 @@ int usb_port_suspend(struct usb_device *udev, pm_message_t msg) usb_enable_ltm(udev); err_ltm: /* Try to enable USB2 hardware LPM again */ - if (udev->usb2_hw_lpm_capable == 1) - usb_enable_usb2_hardware_lpm(udev); + usb_enable_usb2_hardware_lpm(udev); if (udev->do_remote_wakeup) (void) usb_disable_remote_wakeup(udev); @@ -3574,8 +3572,7 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg) hub_port_logical_disconnect(hub, port1); } else { /* Try to enable USB2 hardware LPM */ - if (udev->usb2_hw_lpm_capable == 1) - usb_enable_usb2_hardware_lpm(udev); + usb_enable_usb2_hardware_lpm(udev); /* Try to enable USB3 LTM */ usb_enable_ltm(udev); @@ -5680,8 +5677,7 @@ static int usb_reset_and_verify_device(struct usb_device *udev) /* Disable USB2 hardware LPM. * It will be re-enabled by the enumeration process. */ - if (udev->usb2_hw_lpm_enabled == 1) - usb_disable_usb2_hardware_lpm(udev); + usb_disable_usb2_hardware_lpm(udev); /* Disable LPM while we reset the device and reinstall the alt settings. * Device-initiated LPM, and system exit latency settings are cleared diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index 35951ae..4f33eb6 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -1243,8 +1243,7 @@ void usb_disable_device(struct usb_device *dev, int skip_ep0) dev->actconfig->interface[i] = NULL; } - if (dev->usb2_hw_lpm_enabled == 1) - usb_disable_usb2_hardware_lpm(dev); + usb_disable_usb2_hardware_lpm(dev); usb_unlocked_disable_lpm(dev); usb_disable_ltm(dev); -- 2.7.4