kernel/linux.git/include/linux/usb.h, branch v3.6.8

USB: add USB_VENDOR_AND_INTERFACE_INFO() macro

2012-07-17T00:43:04+00:00

A lot of Broadcom Bluetooth devices provides vendor specific interface class and we are getting flooded by patches adding new device support. This change will help us enable support for any other Broadcom with vendor specific device that arrives in the future. Only the product id changes for those devices, so this macro would be perfect for us: { USB_VENDOR_AND_INTERFACE_INFO(0x0a5c, 0xff, 0x01, 0x01) } Signed-off-by: Marcel Holtmann Signed-off-by: Gustavo Padovan Acked-by: Henrik Rydberg Signed-off-by: Greg Kroah-Hartman

USB: remove 8 bytes of padding from usb_host_interface on 64 bit builds

2012-07-17T00:21:29+00:00

Reorder elements in the usb_host_interface structure to remove 8 bytes of padding on 64 bit builds , and so shrink it's size to 40 bytes. usb_interface_descriptor is a odd size which leaves a gap that is not big enough to hold a pointer, so moving extralen into that gap removes the need for more padding. Signed-off-by: Richard Kennedy Signed-off-by: Greg Kroah-Hartman

USB: Add a sysfs file to show LTM capabilities.

2012-07-11T11:06:48+00:00

USB 3.0 devices can optionally support Latency Tolerance Messaging (LTM). Add a new sysfs file in the device directory to show whether a device is LTM capable. This file will be present for both USB 2.0 and USB 3.0 devices. Signed-off-by: Sarah Sharp

USB: Enable Latency Tolerance Messaging (LTM).

2012-07-11T11:06:48+00:00

USB 3.0 devices may optionally support a new feature called Latency Tolerance Messaging. If both the xHCI host controller and the device support LTM, it should be turned on in order to give the system hardware a better clue about the latency tolerance values of its PCI devices. Once a Set Feature request to enable LTM is received, the USB 3.0 device will begin to send LTM updates as its buffers fill or empty, and it can tolerate more or less latency. The USB 3.0 spec, section C.4.2 says that LTM should be disabled just before the device is placed into suspend. Then the device will send an updated LTM notification, so that the system doesn't think it should remain in an active state in order to satisfy the latency requirements of the suspended device. The Set and Clear Feature LTM enable command can only be sent to a configured device. The device will respond with an error if that command is sent while it is in the Default or Addressed state. Make sure to check udev->actconfig in usb_enable_ltm() and usb_disable_ltm(), and don't send those commands when the device is unconfigured. LTM should be enabled once a new configuration is installed in usb_set_configuration(). If we end up sending duplicate Set Feature LTM Enable commands on a switch from one installed configuration to another configuration, that should be harmless. Make sure that LTM is disabled before the device is unconfigured in usb_disable_device(). If no drivers are bound to the device, it doesn't make sense to allow the device to control the latency tolerance of the xHCI host controller. Signed-off-by: Sarah Sharp

USB: Remove unused LPM variable.

2012-07-11T11:06:47+00:00

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 Cc: stable@vger.kernel.org

usbdevfs: Add a USBDEVFS_GET_CAPABILITIES ioctl

2012-07-06T17:53:19+00:00

There are a few (new) usbdevfs capabilities which an application cannot discover in any other way then checking the kernel version. There are 3 problems with this: 1) It is just not very pretty. 2) Given the tendency of enterprise distros to backport stuff it is not reliable. 3) As discussed in length on the mailinglist, USBDEVFS_URB_BULK_CONTINUATION does not work as it should when combined with USBDEVFS_URB_SHORT_NOT_OK (which is its intended use) on devices attached to an XHCI controller. So the availability of these features can be host controller dependent, making depending on them based on the kernel version not a good idea. This patch besides adding the new ioctl also adds flags for the following existing capabilities: USBDEVFS_CAP_ZERO_PACKET, available since 2.6.31 USBDEVFS_CAP_BULK_CONTINUATION, available since 2.6.32, except for XHCI USBDEVFS_CAP_NO_PACKET_SIZE_LIM, available since 3.3 Note that this patch only does not advertise the USBDEVFS_URB_BULK_CONTINUATION cap for XHCI controllers, bulk transfers with this flag set will still be accepted when submitted to XHCI controllers. Returning -EINVAL for them would break existing apps, and in most cases the troublesome scenario wrt USBDEVFS_URB_SHORT_NOT_OK urbs on XHCI controllers will never get hit, so this would break working use cases. The disadvantage of not returning -EINVAL is that cases were it is causing real trouble may go undetected / the cause of the trouble may be unclear, but this is the best we can do. Signed-off-by: Hans de Goede Acked-by: Alan Stern Acked-by: Sarah Sharp Signed-off-by: Greg Kroah-Hartman

USB: allow match on bInterfaceNumber

2012-06-13T22:40:09+00:00

Some composite USB devices provide multiple interfaces with different functions, all using "vendor-specific" for class/subclass/protocol. Another OS use interface numbers to match the driver and interface. It seems these devices are designed with that in mind - using static interface numbers for the different functions. This adds support for matching against the bInterfaceNumber, allowing such devices to be supported without having to resort to testing against interface number whitelists and/or blacklists in the probe. Signed-off-by: Bjørn Mork Signed-off-by: Greg Kroah-Hartman

USB: Fix core compile with CONFIG_USB_SUSPEND=n

2012-05-21T16:00:03+00:00

When CONFIG_PM=n, make sure that the usb_[unlocked_][en/dis]able_lpm declarations are visible in include/linux/usb.h, and exported from drivers/usb/core/hub.c. Before this patch, if CONFIG_USB_SUSPEND was turned off, it would cause build errors: drivers/usb/core/hub.c: In function 'usb_disable_lpm': drivers/usb/core/hub.c:3394:2: error: implicit declaration of function 'usb_enable_lpm' [-Werror=implicit-function-declaration] drivers/usb/core/hub.c: At top level: drivers/usb/core/hub.c:3424:6: warning: conflicting types for 'usb_enable_lpm' [enabled by default] drivers/usb/core/hub.c:3394:2: note: previous implicit declaration of 'usb_enable_lpm' was here drivers/usb/core/driver.c: In function 'usb_probe_interface': drivers/usb/core/driver.c:339:2: error: implicit declaration of function 'usb_unlocked_disable_lpm' [-Werror=implicit-function-declaration] drivers/usb/core/driver.c:364:3: error: implicit declaration of function 'usb_unlocked_enable_lpm' [-Werror=implicit-function-declaration] drivers/usb/core/message.c: In function 'usb_set_interface': drivers/usb/core/message.c:1314:2: error: implicit declaration of function 'usb_disable_lpm' [-Werror=implicit-function-declaration] drivers/usb/core/message.c:1323:3: error: implicit declaration of function 'usb_enable_lpm' [-Werror=implicit-function-declaration] drivers/usb/core/message.c:1368:2: error: implicit declaration of function 'usb_unlocked_enable_lpm' [-Werror=implicit-function-declaration] Signed-off-by: Sarah Sharp Reported-by: Stephen Rothwell Reported-by: Chen Peter-B29397

USB: Disable USB 3.0 LPM in critical sections.

2012-05-18T22:41:59+00:00

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

USB: Add support to enable/disable USB3 link states.

2012-05-18T22:41:58+00:00

There are various functions within the USB core that will need to disable USB 3.0 link power states. For example, when a USB device driver is being bound to an interface, we need to disable USB 3.0 LPM until we know if the driver will allow hub-initiated LPM transitions. Another example is when the USB core is switching alternate interface settings. The USB 3.0 timeout values are dependent on what endpoints are enabled, so we want to ensure that LPM is disabled until the new alt setting is fully installed. Multiple functions need to disable LPM, and those functions can even be nested. For example, usb_bind_interface() could disable LPM, and then call into the driver probe function, which may attempt to switch to a different alt setting. Therefore, we need to keep a count of the number of functions that require LPM to be disabled at any point in time. Introduce two new USB core API calls, usb_disable_lpm() and usb_enable_lpm(). These functions increment and decrement a new variable in the usb_device, lpm_disable_count. If usb_disable_lpm() fails, it will call usb_enable_lpm() in order to balance the lpm_disable_count. These two new functions must be called with the bandwidth_mutex locked. If the bandwidth_mutex is not already held by the caller, it should instead call usb_unlocked_disable_lpm() and usb_enable_lpm(), which take the bandwidth_mutex before calling usb_disable_lpm() and usb_enable_lpm(), respectively. Introduce a new variable (timeout) in the usb3_lpm_params structure to keep track of the currently enabled U1/U2 timeout values. When usb_disable_lpm() is called, and the USB device has the U1 or U2 timeouts set to a non-zero value (meaning either device-initiated or hub-initiated LPM is enabled), attempt to disable LPM, regardless of the state of the lpm_disable_count. We want to ensure that all callers can be guaranteed that LPM is disabled if usb_disable_lpm() returns zero. Otherwise the following scenario could occur: 1. Driver A is being bound to interface 1. usb_probe_interface() disables LPM. Driver A doesn't care if hub-initiated LPM is enabled, so even though usb_disable_lpm() fails, the probe of the driver continues, and the bandwidth mutex is dropped. 2. Meanwhile, Driver B is being bound to interface 2. usb_probe_interface() grabs the bandwidth mutex and calls usb_disable_lpm(). That call should attempt to disable LPM, even though the lpm_disable_count is set to 1 by Driver A. For usb_enable_lpm(), we attempt to enable LPM only when the lpm_disable_count is zero. If some step in enabling LPM fails, it will only have a minimal impact on power consumption, and all USB device drivers should still work properly. Therefore don't bother to return any error codes. Don't enable device-initiated LPM if the device is unconfigured. The USB device will only accept the U1/U2_ENABLE control transfers in the configured state. Do enable hub-initiated LPM in that case, since devices are allowed to accept the LGO_Ux link commands in any state. Don't enable or disable LPM if the device is marked as not being LPM capable. This can happen if: - the USB device doesn't have a SS BOS descriptor, - the device's parent hub has a zeroed bHeaderDecodeLatency value, or - the xHCI host doesn't support LPM. Signed-off-by: Sarah Sharp Cc: Andiry Xu Cc: Alan Stern Signed-off-by: Sarah Sharp