lkml.org 
[lkml]   [2019]   [May]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.4 012/266] USB: Consolidate LPM checks to avoid enabling LPM twice
Date
From: Kai-Heng Feng <kai.heng.feng@canonical.com>

commit d7a6c0ce8d26412903c7981503bad9e1cc7c45d2 upstream.

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 <kai.heng.feng@canonical.com>
Cc: stable <stable@vger.kernel.org> # after much soaking
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
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(-)

--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -1893,9 +1893,6 @@ static int usb_set_usb2_hardware_lpm(str
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)
@@ -1907,11 +1904,19 @@ static int usb_set_usb2_hardware_lpm(str

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);
}

--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -3116,8 +3116,7 @@ int usb_port_suspend(struct usb_device *
}

/* 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.");
@@ -3163,8 +3162,7 @@ int usb_port_suspend(struct usb_device *
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);
@@ -3443,8 +3441,7 @@ int usb_port_resume(struct usb_device *u
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 and LPM */
usb_enable_ltm(udev);
@@ -5415,8 +5412,7 @@ static int usb_reset_and_verify_device(s
/* 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 and LTM while we reset the device and reinstall the alt
* settings. Device-initiated LPM settings, and system exit latency
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -1184,8 +1184,7 @@ void usb_disable_device(struct usb_devic
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);


\
 
 \ /
  Last update: 2019-05-15 14:40    [W:0.526 / U:15.212 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site