user/sven/linux.git/include/linux/usb.h, branch v3.14.68

usb: define a generic USB_RESUME_TIMEOUT macro

2015-05-06T19:59:11Z

commit 62f0342de1f012f3e90607d39e20fce811391169 upstream. Every USB Host controller should use this new macro to define for how long resume signalling should be driven on the bus. Currently, almost every single USB controller is using a 20ms timeout for resume signalling. That's problematic for two reasons: a) sometimes that 20ms timer expires a little before 20ms, which makes us fail certification b) some (many) devices actually need more than 20ms resume signalling. Sure, in case of (b) we can state that the device is against the USB spec, but the fact is that we have no control over which device the certification lab will use. We also have no control over which host they will use. Most likely they'll be using a Windows PC which, again, we have no control over how that USB stack is written and how long resume signalling they are using. At the end of the day, we must make sure Linux passes electrical compliance when working as Host or as Device and currently we don't pass compliance as host because we're driving resume signallig for exactly 20ms and that confuses certification test setup resulting in Certification failure. Acked-by: Greg Kroah-Hartman Acked-by: Peter Chen Signed-off-by: Felipe Balbi Signed-off-by: Greg Kroah-Hartman

Revert "usb: xhci: Link TRB must not occur within a USB payload burst"

2014-02-07T22:30:03Z

This reverts commit 35773dac5f862cb1c82ea151eba3e2f6de51ec3e. It's a hack that caused regressions in the usb-storage and userspace USB drivers that use usbfs and libusb. Commit 70cabb7d992f "xhci 1.0: Limit arbitrarily-aligned scatter gather." should fix the issues seen with the ax88179_178a driver on xHCI 1.0 hosts, without causing regressions. Signed-off-by: Sarah Sharp Cc: stable@vger.kernel.org # 3.12

usb: core: allow a reference device for new_id

2014-01-11T00:54:35Z

Often, usb drivers need some driver_info to get a device to work. To have access to driver_info when using new_id, allow to pass a reference vendor:product tuple from which new_id will inherit driver_info. Signed-off-by: Wolfram Sang Signed-off-by: Greg Kroah-Hartman

usb: xhci: Link TRB must not occur within a USB payload burst

2013-12-02T19:57:10Z

Section 4.11.7.1 of rev 1.0 of the xhci specification states that a link TRB can only occur at a boundary between underlying USB frames (512 bytes for high speed devices). If this isn't done the USB frames aren't formatted correctly and, for example, the USB3 ethernet ax88179_178a card will stop sending (while still receiving) when running a netperf tcp transmit test with (say) and 8k buffer. This should be a candidate for stable, the ax88179_178a driver defaults to gso and tso enabled so it passes a lot of fragmented skb to the USB stack. Notes from Sarah: Discussion: http://marc.info/?l=linux-usb&m=138384509604981&w=2 This patch fixes a long-standing xHCI driver bug that was revealed by a change in 3.12 in the usb-net driver. Commit 638c5115a794981441246fa8fa5d95c1875af5ba "USBNET: support DMA SG" added support to use bulk endpoint scatter-gather (urb->sg). Only the USB ethernet drivers trigger this bug, because the mass storage driver sends sg list entries in page-sized chunks. This patch only fixes the issue for bulk endpoint scatter-gather. The problem will still occur for periodic endpoints, because hosts will interpret no-op transfers as a request to skip a service interval, which is not what we want. Luckily, the USB core isn't set up for scatter-gather on isochronous endpoints, and no USB drivers use scatter-gather for interrupt endpoints. Document this known limitation so that developers won't try to use urb->sg for interrupt endpoints until this issue is fixed. The more comprehensive fix would be to allow link TRBs in the middle of the endpoint ring and revert this patch, but that fix would touch too much code to be allowed in for stable. This patch should be backported to kernels as old as 3.12, that contain the commit 638c5115a794981441246fa8fa5d95c1875af5ba "USBNET: support DMA SG". Without this patch, the USB network device gets wedged, and stops sending packets. Mark Lord confirms this patch fixes the regression: http://marc.info/?l=linux-netdev&m=138487107625966&w=2 Signed-off-by: David Laight Signed-off-by: Sarah Sharp Tested-by: Mark Lord Cc: stable@vger.kernel.org

usb: Don't enable USB 2.0 Link PM by default.

2013-10-16T19:24:19Z

How it's supposed to work: -------------------------- USB 2.0 Link PM is a lower power state that some newer USB 2.0 devices support. USB 3.0 devices certified by the USB-IF are required to support it if they are plugged into a USB 2.0 only port, or a USB 2.0 cable is used. USB 2.0 Link PM requires both a USB device and a host controller that supports USB 2.0 hardware-enabled LPM. USB 2.0 Link PM is designed to be enabled once by software, and the host hardware handles transitions to the L1 state automatically. The premise of USB 2.0 Link PM is to be able to put the device into a lower power link state when the bus is idle or the device NAKs USB IN transfers for a specified amount of time. ...but hardware is broken: -------------------------- It turns out many USB 3.0 devices claim to support USB 2.0 Link PM (by setting the LPM bit in their USB 2.0 BOS descriptor), but they don't actually implement it correctly. This manifests as the USB device refusing to respond to transfers when it is plugged into a USB 2.0 only port under the Haswell-ULT/Lynx Point LP xHCI host. These devices pass the xHCI driver's simple test to enable USB 2.0 Link PM, wait for the port to enter L1, and then bring it back into L0. They only start to break when L1 entry is interleaved with transfers. Some devices then fail to respond to the next control transfer (usually a Set Configuration). This results in devices never enumerating. Other mass storage devices (such as a later model Western Digital My Passport USB 3.0 hard drive) respond fine to going into L1 between control transfers. They ACK the entry, come out of L1 when the host needs to send a control transfer, and respond properly to those control transfers. However, when the first READ10 SCSI command is sent, the device NAKs the data phase while it's reading from the spinning disk. Eventually, the host requests to put the link into L1, and the device ACKs that request. Then it never responds to the data phase of the READ10 command. This results in not being able to read from the drive. Some mass storage devices (like the Corsair Survivor USB 3.0 flash drive) are well behaved. They ACK the entry into L1 during control transfers, and when SCSI commands start coming in, they NAK the requests to go into L1, because they need to be at full power. Not all USB 3.0 devices advertise USB 2.0 link PM support. My Point Grey USB 3.0 webcam advertises itself as a USB 2.1 device, but doesn't have a USB 2.0 BOS descriptor, so we don't enable USB 2.0 Link PM. I suspect that means the device isn't certified. What do we do about it? ----------------------- There's really no good way for the kernel to test these devices. Therefore, the kernel needs to disable USB 2.0 Link PM by default, and distros will have to enable it by writing 1 to the sysfs file /sys/bus/usb/devices/../power/usb2_hardware_lpm. Rip out the xHCI Link PM test, since it's not sufficient to detect these buggy devices, and don't automatically enable LPM after the device is addressed. This patch should be backported to kernels as old as 3.11, that contain the commit a558ccdcc71c7770c5e80c926a31cfe8a3892a09 "usb: xhci: add USB2 Link power management BESL support". Without this fix, some USB 3.0 devices will not enumerate or work properly under USB 2.0 ports on Haswell-ULT systems. Signed-off-by: Sarah Sharp Cc: stable@vger.kernel.org

usb-anchor: Delay usb_wait_anchor_empty_timeout wake up till completion is done

2013-10-11T23:33:58Z

usb_wait_anchor_empty_timeout() should wait till the completion handler has run. Both the zd1211rw driver and the uas driver (in its task mgmt) depend on the completion handler having completed when usb_wait_anchor_empty_timeout() returns, as they read state set by the completion handler after an usb_wait_anchor_empty_timeout() call. But __usb_hcd_giveback_urb() calls usb_unanchor_urb before calling the completion handler. This is necessary as the completion handler may re-submit and re-anchor the urb. But this introduces a race where the state these drivers want to read has not been set yet by the completion handler (this race is easily triggered with the uas task mgmt code). I've considered adding an anchor_count to struct urb, which would be incremented on anchor and decremented on unanchor, and then only actually do the anchor / unanchor on 0 -> 1 and 1 -> 0 transtions, combined with moving the unanchor call in hcd_giveback_urb to after calling the completion handler. But this will only work if urb's are only re-anchored to the same anchor as they were anchored to before the completion handler ran. And at least one driver re-anchors to another anchor from the completion handler (rtlwifi). So I have come up with this patch instead, which adds the ability to suspend wakeups of usb_wait_anchor_empty_timeout() waiters to the usb_anchor functionality, and uses this in __usb_hcd_giveback_urb() to delay wake-ups until the completion handler has run. Signed-off-by: Hans de Goede Acked-by: Oliver Neukum Signed-off-by: Greg Kroah-Hartman

usb-anchor: Ensure poisened gets initialized to 0

2013-10-11T23:33:58Z

And do so in a way which ensures that any fields added in the future will also get properly zero-ed. Signed-off-by: Hans de Goede Acked-by: Oliver Neukum Signed-off-by: Greg Kroah-Hartman

usb-core: Make usb_free_streams return an error

2013-09-17T16:49:24Z

The hcd-driver free_streams method can return an error, so lets properly propagate that. Signed-off-by: Hans de Goede Signed-off-by: Greg Kroah-Hartman

USB: introduce usb_device_no_sg_constraint() helper

2013-08-12T18:56:16Z

Some host controllers(such as xHCI) can support building packet from discontinuous buffers, so introduce one flag and helper for this kind of host controllers, then the feature can help some applications(such as usbnet) by supporting arbitrary length of sg buffers. Acked-by: Alan Stern Signed-off-by: Ming Lei Reviewed-by: Eric Dumazet Signed-off-by: Greg Kroah-Hartman

usb: fix some scripts/kernel-doc warnings

2013-08-03T03:30:14Z

When building the htmldocs (in verbose mode), scripts/kernel-doc reports the following type of warnings: Warning(drivers/usb/core/usb.c:76): No description found for return value of 'usb_find_alt_setting' Fix them by: - adding some missing descriptions of return values - using "Return" sections for those descriptions Signed-off-by: Yacine Belkadi Signed-off-by: Greg Kroah-Hartman