/openbmc/linux/drivers/usb/core/ |
H A D | message.c | diff 249719121bc2b841bdfcab5eb21b10d8b871743b Thu Jul 05 16:09:30 CDT 2012 Sarah Sharp <sarah.a.sharp@linux.intel.com> USB: Fix LPM disable count mismatch on driver unbind.
When a user runs `echo 0 > bConfigurationValue` for a USB 3.0 device, usb_disable_device() is called. This function disables all drivers, deallocates interfaces, and sets the device configuration value to 0 (unconfigured).
With the new scheme to ensure that unconfigured devices have LPM disabled, usb_disable_device() must call usb_unlocked_disable_lpm() once it unconfigures the device.
This commit should be backported to kernels as old as 3.5, that contain the commit 8306095fd2c1100e8244c09bf560f97aca5a311d "USB: Disable USB 3.0 LPM in critical sections."
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable@vger.kernel.org diff 9cf65991dd93ac3d5f97f536171c388918b7c1a9 Wed Jul 04 01:22:38 CDT 2012 Sarah Sharp <sarah.a.sharp@linux.intel.com> USB: Disable LPM while the device is unconfigured.
The USB 3.0 Set/Clear Feature U1/U2 Enable cannot be sent to a device in the Default or Addressed state. It can only be sent to a configured device. Change the USB core to initialize the LPM disable count to 1 (disabled), which reflects this limitation.
Change usb_set_configuration() to ensure that if the device is unconfigured on entry, usb_lpm_disable() is not called. This avoids sending the Clear Feature U1/U2 when the device is in the Addressed state. When usb_set_configuration() exits with a successfully installed configuration, usb_lpm_enable() will be called.
Once the new configuration is installed, make sure usb_set_configuration() only calls usb_enable_lpm() if the device moved to the Configured state. If we have unconfigured the device by sending it a Set Configuration for config 0, don't enable LPM.
This commit should be backported to kernels as old as 3.5, that contain the commit 8306095fd2c1100e8244c09bf560f97aca5a311d "USB: Disable USB 3.0 LPM in critical sections."
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable@vger.kernel.org diff 8306095fd2c1100e8244c09bf560f97aca5a311d Wed May 02 16:25:52 CDT 2012 Sarah Sharp <sarah.a.sharp@linux.intel.com> USB: Disable USB 3.0 LPM in critical sections.
There are several places where the USB core needs to disable USB 3.0 Link PM: - usb_bind_interface - usb_unbind_interface - usb_driver_claim_interface - usb_port_suspend/usb_port_resume - usb_reset_and_verify_device - usb_set_interface - usb_reset_configuration - usb_set_configuration
Use the new LPM disable/enable functions to temporarily disable LPM around these critical sections.
We need to protect the critical section around binding and unbinding USB interface drivers. USB drivers may want to disable hub-initiated USB 3.0 LPM, which will change the value of the U1/U2 timeouts that the xHCI driver will install. We need to disable LPM completely until the driver is bound to the interface, and the driver has a chance to enable whatever alternate interface setting it needs in its probe routine. Then re-enable USB3 LPM, and recalculate the U1/U2 timeout values.
We also need to disable LPM in usb_driver_claim_interface, because drivers like usbfs can bind to an interface through that function. Note, there is no way currently for userspace drivers to disable hub-initiated USB 3.0 LPM. Revisit this later.
When a driver is unbound, the U1/U2 timeouts may change because we are unbinding the last driver that needed hub-initiated USB 3.0 LPM to be disabled.
USB LPM must be disabled when a USB device is going to be suspended. The USB 3.0 spec does not define a state transition from U1 or U2 into U3, so we need to bring the device into U0 by disabling LPM before we can place it into U3. Therefore, call usb_unlocked_disable_lpm() in usb_port_suspend(), and call usb_unlocked_enable_lpm() in usb_port_resume(). If the port suspend fails, make sure to re-enable LPM by calling usb_unlocked_enable_lpm(), since usb_port_resume() will not be called on a failed port suspend.
USB 3.0 devices lose their USB 3.0 LPM settings (including whether USB device-initiated LPM is enabled) across device suspend. Therefore, disable LPM before the device will be reset in usb_reset_and_verify_device(), and re-enable LPM after the reset is complete and the configuration/alt settings are re-installed.
The calculated U1/U2 timeout values are heavily dependent on what USB device endpoints are currently enabled. When any of the enabled endpoints on the device might change, due to a new configuration, or new alternate interface setting, we need to first disable USB 3.0 LPM, add or delete endpoints from the xHCI schedule, install the new interfaces and alt settings, and then re-enable LPM. Do this in usb_set_interface, usb_reset_configuration, and usb_set_configuration.
Basically, there is a call to disable and then enable LPM in all functions that lock the bandwidth_mutex. One exception is usb_disable_device, because the device is disconnecting or otherwise going away, and we should not care about whether USB 3.0 LPM is enabled.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
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H A D | driver.c | diff d01f87c0ffa96cb44faa78710711eb6e974b891c Thu Oct 04 11:53:43 CDT 2012 Sarah Sharp <sarah.a.sharp@linux.intel.com> USB: Enable LPM after a failed probe.
Before a driver is probed, we want to disable USB 3.0 Link Power Management (LPM), in case the driver needs hub-initiated LPM disabled. After the probe finishes, we want to attempt to re-enable LPM, order to balance the LPM ref count.
When a probe fails (such as when libusual doesn't want to bind to a USB 3.0 mass storage device), make sure to balance the LPM ref counts by re-enabling LPM.
This patch should be backported to kernels as old as 3.5, that contain the commit 8306095fd2c1100e8244c09bf560f97aca5a311d "USB: Disable USB 3.0 LPM in critical sections."
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable@vger.kernel.org diff 8306095fd2c1100e8244c09bf560f97aca5a311d Wed May 02 16:25:52 CDT 2012 Sarah Sharp <sarah.a.sharp@linux.intel.com> USB: Disable USB 3.0 LPM in critical sections.
There are several places where the USB core needs to disable USB 3.0 Link PM: - usb_bind_interface - usb_unbind_interface - usb_driver_claim_interface - usb_port_suspend/usb_port_resume - usb_reset_and_verify_device - usb_set_interface - usb_reset_configuration - usb_set_configuration
Use the new LPM disable/enable functions to temporarily disable LPM around these critical sections.
We need to protect the critical section around binding and unbinding USB interface drivers. USB drivers may want to disable hub-initiated USB 3.0 LPM, which will change the value of the U1/U2 timeouts that the xHCI driver will install. We need to disable LPM completely until the driver is bound to the interface, and the driver has a chance to enable whatever alternate interface setting it needs in its probe routine. Then re-enable USB3 LPM, and recalculate the U1/U2 timeout values.
We also need to disable LPM in usb_driver_claim_interface, because drivers like usbfs can bind to an interface through that function. Note, there is no way currently for userspace drivers to disable hub-initiated USB 3.0 LPM. Revisit this later.
When a driver is unbound, the U1/U2 timeouts may change because we are unbinding the last driver that needed hub-initiated USB 3.0 LPM to be disabled.
USB LPM must be disabled when a USB device is going to be suspended. The USB 3.0 spec does not define a state transition from U1 or U2 into U3, so we need to bring the device into U0 by disabling LPM before we can place it into U3. Therefore, call usb_unlocked_disable_lpm() in usb_port_suspend(), and call usb_unlocked_enable_lpm() in usb_port_resume(). If the port suspend fails, make sure to re-enable LPM by calling usb_unlocked_enable_lpm(), since usb_port_resume() will not be called on a failed port suspend.
USB 3.0 devices lose their USB 3.0 LPM settings (including whether USB device-initiated LPM is enabled) across device suspend. Therefore, disable LPM before the device will be reset in usb_reset_and_verify_device(), and re-enable LPM after the reset is complete and the configuration/alt settings are re-installed.
The calculated U1/U2 timeout values are heavily dependent on what USB device endpoints are currently enabled. When any of the enabled endpoints on the device might change, due to a new configuration, or new alternate interface setting, we need to first disable USB 3.0 LPM, add or delete endpoints from the xHCI schedule, install the new interfaces and alt settings, and then re-enable LPM. Do this in usb_set_interface, usb_reset_configuration, and usb_set_configuration.
Basically, there is a call to disable and then enable LPM in all functions that lock the bandwidth_mutex. One exception is usb_disable_device, because the device is disconnecting or otherwise going away, and we should not care about whether USB 3.0 LPM is enabled.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
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H A D | hub.c | diff aa5ceae24bf8dff1d6fe87c6c4b08e69c6d33550 Tue Jul 30 14:39:02 CDT 2013 Alan Stern <stern@rowland.harvard.edu> USB: handle LPM errors during device suspend correctly
The hub driver's usb_port_suspend() routine doesn't handle errors related to Link Power Management properly. It always returns failure, it doesn't try to clean up the wakeup setting, (in the case of system sleep) it doesn't try to go ahead with the port suspend regardless, and it doesn't try to apply the new power-off mechanism.
This patch fixes these problems.
Note: Sarah fixed this patch to apply against 3.11, since the original commit (4fae6f0fa86f92e6bc7429371b1e177ad0aaac66 "USB: handle LPM errors during device suspend correctly") called usb_disable_remote_wakeup, which won't be added until 3.12.
This patch should be backported to kernels as old as 3.5, that contain the commit 8306095fd2c1100e8244c09bf560f97aca5a311d "USB: Disable USB 3.0 LPM in critical sections.". There will be merge conflicts, since LTM wasn't added until 3.6.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable@vger.kernel.org diff 6d1d051330ee096f575523647fbd8ffe703600b5 Wed Jul 04 00:49:04 CDT 2012 Sarah Sharp <sarah.a.sharp@linux.intel.com> USB: Fix LPM disable/enable during device reset.
The USB 3.0 specification says that sending a Set Feature or Clear Feature for U1/U2 Enable is not a valid request when the device is in the Default or Addressed state. It is only valid when the device is in the Configured state.
The original LPM patch attempted to disable LPM after the device had been reset by hub_port_init(), before it had the configuration reinstalled. The TI hub I tested with did not fail the Clear Feature U1/U2 Enable request that khubd sent while it was in the addressed state, which is why I didn't catch it.
Move the LPM disable before the device reset, so that we can send the Clear Feature U1/U2 Enable successfully, and balance the LPM disable count.
Also delete any calls to usb_enable_lpm() on error paths that lead to re-enumeration. The calls will fail because the device isn't configured, and it's not useful to balance the LPM disable count because the usb_device is about to be destroyed before re-enumeration.
Fix the early exit path ("done" label) to call usb_enable_lpm() to balance the LPM disable count.
Note that calling usb_reset_and_verify_device() with an unconfigured device may fail on the first call to usb_disable_lpm(). That's because the LPM disable count is initialized to 0 (LPM enabled), and usb_disable_lpm() will attempt to send a Clear Feature U1/U2 request to a device in the Addressed state. The next patch will fix that.
This commit should be backported to kernels as old as 3.5, that contain the commit 8306095fd2c1100e8244c09bf560f97aca5a311d "USB: Disable USB 3.0 LPM in critical sections."
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable@vger.kernel.org diff 8306095fd2c1100e8244c09bf560f97aca5a311d Wed May 02 16:25:52 CDT 2012 Sarah Sharp <sarah.a.sharp@linux.intel.com> USB: Disable USB 3.0 LPM in critical sections.
There are several places where the USB core needs to disable USB 3.0 Link PM: - usb_bind_interface - usb_unbind_interface - usb_driver_claim_interface - usb_port_suspend/usb_port_resume - usb_reset_and_verify_device - usb_set_interface - usb_reset_configuration - usb_set_configuration
Use the new LPM disable/enable functions to temporarily disable LPM around these critical sections.
We need to protect the critical section around binding and unbinding USB interface drivers. USB drivers may want to disable hub-initiated USB 3.0 LPM, which will change the value of the U1/U2 timeouts that the xHCI driver will install. We need to disable LPM completely until the driver is bound to the interface, and the driver has a chance to enable whatever alternate interface setting it needs in its probe routine. Then re-enable USB3 LPM, and recalculate the U1/U2 timeout values.
We also need to disable LPM in usb_driver_claim_interface, because drivers like usbfs can bind to an interface through that function. Note, there is no way currently for userspace drivers to disable hub-initiated USB 3.0 LPM. Revisit this later.
When a driver is unbound, the U1/U2 timeouts may change because we are unbinding the last driver that needed hub-initiated USB 3.0 LPM to be disabled.
USB LPM must be disabled when a USB device is going to be suspended. The USB 3.0 spec does not define a state transition from U1 or U2 into U3, so we need to bring the device into U0 by disabling LPM before we can place it into U3. Therefore, call usb_unlocked_disable_lpm() in usb_port_suspend(), and call usb_unlocked_enable_lpm() in usb_port_resume(). If the port suspend fails, make sure to re-enable LPM by calling usb_unlocked_enable_lpm(), since usb_port_resume() will not be called on a failed port suspend.
USB 3.0 devices lose their USB 3.0 LPM settings (including whether USB device-initiated LPM is enabled) across device suspend. Therefore, disable LPM before the device will be reset in usb_reset_and_verify_device(), and re-enable LPM after the reset is complete and the configuration/alt settings are re-installed.
The calculated U1/U2 timeout values are heavily dependent on what USB device endpoints are currently enabled. When any of the enabled endpoints on the device might change, due to a new configuration, or new alternate interface setting, we need to first disable USB 3.0 LPM, add or delete endpoints from the xHCI schedule, install the new interfaces and alt settings, and then re-enable LPM. Do this in usb_set_interface, usb_reset_configuration, and usb_set_configuration.
Basically, there is a call to disable and then enable LPM in all functions that lock the bandwidth_mutex. One exception is usb_disable_device, because the device is disconnecting or otherwise going away, and we should not care about whether USB 3.0 LPM is enabled.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
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H A D | usb.c | diff 9cf65991dd93ac3d5f97f536171c388918b7c1a9 Wed Jul 04 01:22:38 CDT 2012 Sarah Sharp <sarah.a.sharp@linux.intel.com> USB: Disable LPM while the device is unconfigured.
The USB 3.0 Set/Clear Feature U1/U2 Enable cannot be sent to a device in the Default or Addressed state. It can only be sent to a configured device. Change the USB core to initialize the LPM disable count to 1 (disabled), which reflects this limitation.
Change usb_set_configuration() to ensure that if the device is unconfigured on entry, usb_lpm_disable() is not called. This avoids sending the Clear Feature U1/U2 when the device is in the Addressed state. When usb_set_configuration() exits with a successfully installed configuration, usb_lpm_enable() will be called.
Once the new configuration is installed, make sure usb_set_configuration() only calls usb_enable_lpm() if the device moved to the Configured state. If we have unconfigured the device by sending it a Set Configuration for config 0, don't enable LPM.
This commit should be backported to kernels as old as 3.5, that contain the commit 8306095fd2c1100e8244c09bf560f97aca5a311d "USB: Disable USB 3.0 LPM in critical sections."
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable@vger.kernel.org
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/openbmc/linux/include/linux/ |
H A D | usb.h | diff c5c4bdf02e518a281b229ae0891b346919e2d291 Thu Jul 05 11:41:22 CDT 2012 Sarah Sharp <sarah.a.sharp@linux.intel.com> USB: Remove unused LPM variable.
hub_initiated_lpm_disable_count is not used by any code, so remove it.
This commit should be backported to kernels as old as 3.5, that contain the commit 8306095fd2c1100e8244c09bf560f97aca5a311d "USB: Disable USB 3.0 LPM in critical sections."
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable@vger.kernel.org diff 8306095fd2c1100e8244c09bf560f97aca5a311d Wed May 02 16:25:52 CDT 2012 Sarah Sharp <sarah.a.sharp@linux.intel.com> USB: Disable USB 3.0 LPM in critical sections.
There are several places where the USB core needs to disable USB 3.0 Link PM: - usb_bind_interface - usb_unbind_interface - usb_driver_claim_interface - usb_port_suspend/usb_port_resume - usb_reset_and_verify_device - usb_set_interface - usb_reset_configuration - usb_set_configuration
Use the new LPM disable/enable functions to temporarily disable LPM around these critical sections.
We need to protect the critical section around binding and unbinding USB interface drivers. USB drivers may want to disable hub-initiated USB 3.0 LPM, which will change the value of the U1/U2 timeouts that the xHCI driver will install. We need to disable LPM completely until the driver is bound to the interface, and the driver has a chance to enable whatever alternate interface setting it needs in its probe routine. Then re-enable USB3 LPM, and recalculate the U1/U2 timeout values.
We also need to disable LPM in usb_driver_claim_interface, because drivers like usbfs can bind to an interface through that function. Note, there is no way currently for userspace drivers to disable hub-initiated USB 3.0 LPM. Revisit this later.
When a driver is unbound, the U1/U2 timeouts may change because we are unbinding the last driver that needed hub-initiated USB 3.0 LPM to be disabled.
USB LPM must be disabled when a USB device is going to be suspended. The USB 3.0 spec does not define a state transition from U1 or U2 into U3, so we need to bring the device into U0 by disabling LPM before we can place it into U3. Therefore, call usb_unlocked_disable_lpm() in usb_port_suspend(), and call usb_unlocked_enable_lpm() in usb_port_resume(). If the port suspend fails, make sure to re-enable LPM by calling usb_unlocked_enable_lpm(), since usb_port_resume() will not be called on a failed port suspend.
USB 3.0 devices lose their USB 3.0 LPM settings (including whether USB device-initiated LPM is enabled) across device suspend. Therefore, disable LPM before the device will be reset in usb_reset_and_verify_device(), and re-enable LPM after the reset is complete and the configuration/alt settings are re-installed.
The calculated U1/U2 timeout values are heavily dependent on what USB device endpoints are currently enabled. When any of the enabled endpoints on the device might change, due to a new configuration, or new alternate interface setting, we need to first disable USB 3.0 LPM, add or delete endpoints from the xHCI schedule, install the new interfaces and alt settings, and then re-enable LPM. Do this in usb_set_interface, usb_reset_configuration, and usb_set_configuration.
Basically, there is a call to disable and then enable LPM in all functions that lock the bandwidth_mutex. One exception is usb_disable_device, because the device is disconnecting or otherwise going away, and we should not care about whether USB 3.0 LPM is enabled.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
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