Here is the big USB patchset for 4.12-rc1.
Lots of good stuff here, after many many many attempts, the kernel
finally has a working typeC interface, many thanks to the Heikki and
Guenter and others who have taken the time to get this merged. It
wasn't an easy path for them at all.
There's also a staging driver that uses this new api, which is why it's
coming in through this tree.
Along with that, there's the usual huge number of changes for gadget
drivers, xhci, and other stuff. Johan also finally refactored pretty
much every driver that was looking at USB endpoints to do it in a common
way, which will help prevent any "badly-formed" devices from causing
problems in drivers. That too wasn't a simple task.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCWQvEIQ8cZ3JlZ0Brcm9h
aC5jb20ACgkQMUfUDdst+yny4gCePCXxnrQdMWE+IMXf1H1hMubLkVkAn0ZWgQkq
BspgO7ZmGb+9Fpf6YvNz
=nwAu
-----END PGP SIGNATURE-----
Merge tag 'usb-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB updates from Greg KH:
"Here is the big USB patchset for 4.12-rc1.
Lots of good stuff here, after many many many attempts, the kernel
finally has a working typeC interface, many thanks to Heikki and
Guenter and others who have taken the time to get this merged. It
wasn't an easy path for them at all.
There's also a staging driver that uses this new api, which is why
it's coming in through this tree.
Along with that, there's the usual huge number of changes for gadget
drivers, xhci, and other stuff. Johan also finally refactored pretty
much every driver that was looking at USB endpoints to do it in a
common way, which will help prevent any "badly-formed" devices from
causing problems in drivers. That too wasn't a simple task.
All of these have been in linux-next for a while with no reported
issues"
* tag 'usb-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (263 commits)
staging: typec: Fairchild FUSB302 Type-c chip driver
staging: typec: Type-C Port Controller Interface driver (tcpci)
staging: typec: USB Type-C Port Manager (tcpm)
usb: host: xhci: remove #ifdef around PM functions
usb: musb: don't mark of_dev_auxdata as initdata
usb: misc: legousbtower: Fix buffers on stack
USB: Revert "cdc-wdm: fix "out-of-sync" due to missing notifications"
usb: Make sure usb/phy/of gets built-in
USB: storage: e-mail update in drivers/usb/storage/unusual_devs.h
usb: host: xhci: print correct command ring address
usb: host: xhci: delete sp_dma_buffers for scratchpad
usb: host: xhci: using correct specification chapter reference for DCBAAP
xhci: switch to pci_alloc_irq_vectors
usb: host: xhci-plat: set resume_quirk() for R-Car controllers
usb: host: xhci-plat: add resume_quirk()
usb: host: xhci-plat: enable clk in resume timing
usb: host: plat: Enable xHCI plat runtime PM
USB: serial: ftdi_sio: add device ID for Microsemi/Arrow SF2PLUS Dev Kit
USB: serial: constify static arrays
usb: fix some references for /proc/bus/usb
...
guide for user-space API documents, rather sparsely populated at the
moment, but it's a start. Markus improved the infrastructure for
converting diagrams. Mauro has converted much of the USB documentation
over to RST. Plus the usual set of fixes, improvements, and tweaks.
There's a bit more than the usual amount of reaching out of Documentation/
to fix comments elsewhere in the tree; I have acks for those where I could
get them.
-----BEGIN PGP SIGNATURE-----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=41m+
-----END PGP SIGNATURE-----
Merge tag 'docs-4.12' of git://git.lwn.net/linux
Pull documentation update from Jonathan Corbet:
"A reasonably busy cycle for documentation this time around. There is a
new guide for user-space API documents, rather sparsely populated at
the moment, but it's a start. Markus improved the infrastructure for
converting diagrams. Mauro has converted much of the USB documentation
over to RST. Plus the usual set of fixes, improvements, and tweaks.
There's a bit more than the usual amount of reaching out of
Documentation/ to fix comments elsewhere in the tree; I have acks for
those where I could get them"
* tag 'docs-4.12' of git://git.lwn.net/linux: (74 commits)
docs: Fix a couple typos
docs: Fix a spelling error in vfio-mediated-device.txt
docs: Fix a spelling error in ioctl-number.txt
MAINTAINERS: update file entry for HSI subsystem
Documentation: allow installing man pages to a user defined directory
Doc/PM: Sync with intel_powerclamp code behavior
zr364xx.rst: usb/devices is now at /sys/kernel/debug/
usb.rst: move documentation from proc_usb_info.txt to USB ReST book
convert philips.txt to ReST and add to media docs
docs-rst: usb: update old usbfs-related documentation
arm: Documentation: update a path name
docs: process/4.Coding.rst: Fix a couple of document refs
docs-rst: fix usb cross-references
usb: gadget.h: be consistent at kernel doc macros
usb: composite.h: fix two warnings when building docs
usb: get rid of some ReST doc build errors
usb.rst: get rid of some Sphinx errors
usb/URB.txt: convert to ReST and update it
usb/persist.txt: convert to ReST and add to driver-api book
usb/hotplug.txt: convert to ReST and add to driver-api book
...
Since when we got rid of usbfs, the /proc/bus/usb is now
elsewhere. Fix references for it.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As some USB documentation files got moved, adjust their
cross-references to their new place.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
We need an space before a numbered list to avoid those warnings:
./drivers/usb/core/message.c:478: ERROR: Unexpected indentation.
./drivers/usb/core/message.c:479: WARNING: Block quote ends without a blank line; unexpected unindent.
./include/linux/usb/composite.h:455: ERROR: Unexpected indentation.
./include/linux/usb/composite.h:456: WARNING: Block quote ends without a blank line; unexpected unindent.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
commit a8c06e407e ("usb: separate out sysdev pointer from
usb_bus") converted to use hcd->self.sysdev for DMA
operations instead of hcd->self.controller but forgot to do
it for one instance.
This gets caught when DMA debugging is enabled since dma map
and unmap end up using different device pointers.
Fix it.
Fixes: a8c06e407e ("usb: separate out sysdev pointer from usb_bus")
Reported-by: Carlos Hernandez <ceh@ti.com>
Acked-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is race condition when two USB class drivers try to call
init_usb_class at the same time and leads to crash.
code path: probe->usb_register_dev->init_usb_class
To solve this, mutex locking has been added in init_usb_class() and
destroy_usb_class().
As pointed by Alan, removed "if (usb_class)" test from destroy_usb_class()
because usb_class can never be NULL there.
Signed-off-by: Ajay Kaher <ajay.kaher@samsung.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Using KASAN, Dmitry found a bug in the rh_call_control() routine: If
buffer allocation fails, the routine returns immediately without
unlinking its URB from the control endpoint, eventually leading to
linked-list corruption.
This patch fixes the problem by jumping to the end of the routine
(where the URB is unlinked) when an allocation failure occurs.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: Dmitry Vyukov <dvyukov@google.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This resolves a merge issue in the gadget code, and we want the USB
fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make the kerneldoc comment for usb_find_common_endpoints_reverse()
self-contained by adding a full description and removing the reference
to usb_find_common_endpoints().
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Several drivers have implemented their endpoint look-up loops in such a
way that they have picked the last endpoint descriptor of the specified
type should more than one such descriptor exist.
To avoid any regressions, add corresponding helpers to lookup endpoints
by searching the endpoint descriptors in reverse order.
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Many USB drivers iterate over the available endpoints to find required
endpoints of a specific type and direction. Typically the endpoints are
required for proper function and a missing endpoint should abort probe.
To facilitate code reuse, add a helper to retrieve common endpoints
(bulk or interrupt, in or out) and four wrappers to find a single
endpoint.
Note that the helpers are marked as __must_check to serve as a reminder
to always verify that all expected endpoints are indeed present. This
also means that any optional endpoints, typically need to be looked up
through separate calls.
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For xhci-hcd platform device, all the DMA parameters are not
configured properly, notably dma ops for dwc3 devices.
The idea here is that you pass in the parent of_node along with
the child device pointer, so it would behave exactly like the
parent already does. The difference is that it also handles all
the other attributes besides the mask.
sysdev will represent the physical device, as seen from firmware
or bus.Splitting the usb_bus->controller field into the
Linux-internal device (used for the sysfs hierarchy, for printks
and for power management) and a new pointer (used for DMA,
DT enumeration and phy lookup) probably covers all that we really
need.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sriram Dash <sriram.dash@nxp.com>
Tested-by: Baolin Wang <baolin.wang@linaro.org>
Tested-by: Brian Norris <briannorris@chromium.org>
Tested-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Tested-by: Vivek Gautam <vivek.gautam@codeaurora.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Sinjan Kumar <sinjank@codeaurora.org>
Cc: David Fisher <david.fisher1@synopsys.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: "Thang Q. Nguyen" <tqnguyen@apm.com>
Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Ming Lei <tom.leiming@gmail.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Dann Frazier <dann.frazier@canonical.com>
Cc: Peter Chen <peter.chen@nxp.com>
Cc: Leo Li <pku.leo@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
While running a bind/unbind stress test with the dwc3 usb driver on rk3399,
the following crash was observed.
Unable to handle kernel NULL pointer dereference at virtual address 00000218
pgd = ffffffc00165f000
[00000218] *pgd=000000000174f003, *pud=000000000174f003,
*pmd=0000000001750003, *pte=00e8000001751713
Internal error: Oops: 96000005 [#1] PREEMPT SMP
Modules linked in: uinput uvcvideo videobuf2_vmalloc cmac
ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat rfcomm
xt_mark fuse bridge stp llc zram btusb btrtl btbcm btintel bluetooth
ip6table_filter mwifiex_pcie mwifiex cfg80211 cdc_ether usbnet r8152 mii joydev
snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device ppp_async
ppp_generic slhc tun
CPU: 1 PID: 29814 Comm: kworker/1:1 Not tainted 4.4.52 #507
Hardware name: Google Kevin (DT)
Workqueue: pm pm_runtime_work
task: ffffffc0ac540000 ti: ffffffc0af4d4000 task.ti: ffffffc0af4d4000
PC is at autosuspend_check+0x74/0x174
LR is at autosuspend_check+0x70/0x174
...
Call trace:
[<ffffffc00080dcc0>] autosuspend_check+0x74/0x174
[<ffffffc000810500>] usb_runtime_idle+0x20/0x40
[<ffffffc000785ae0>] __rpm_callback+0x48/0x7c
[<ffffffc000786af0>] rpm_idle+0x1e8/0x498
[<ffffffc000787cdc>] pm_runtime_work+0x88/0xcc
[<ffffffc000249bb8>] process_one_work+0x390/0x6b8
[<ffffffc00024abcc>] worker_thread+0x480/0x610
[<ffffffc000251a80>] kthread+0x164/0x178
[<ffffffc0002045d0>] ret_from_fork+0x10/0x40
Source:
(gdb) l *0xffffffc00080dcc0
0xffffffc00080dcc0 is in autosuspend_check
(drivers/usb/core/driver.c:1778).
1773 /* We don't need to check interfaces that are
1774 * disabled for runtime PM. Either they are unbound
1775 * or else their drivers don't support autosuspend
1776 * and so they are permanently active.
1777 */
1778 if (intf->dev.power.disable_depth)
1779 continue;
1780 if (atomic_read(&intf->dev.power.usage_count) > 0)
1781 return -EBUSY;
1782 w |= intf->needs_remote_wakeup;
Code analysis shows that intf is set to NULL in usb_disable_device() prior
to setting actconfig to NULL. At the same time, usb_runtime_idle() does not
lock the usb device, and neither does any of the functions in the
traceback. This means that there is no protection against a race condition
where usb_disable_device() is removing dev->actconfig->interface[] pointers
while those are being accessed from autosuspend_check().
To solve the problem, synchronize and validate device state between
autosuspend_check() and usb_disconnect().
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If usb_get_bos_descriptor() returns an error, usb->bos will be NULL.
Nevertheless, it is dereferenced unconditionally in
hub_set_initial_usb2_lpm_policy() if usb2_hw_lpm_capable is set.
This results in a crash.
usb 5-1: unable to get BOS descriptor
...
Unable to handle kernel NULL pointer dereference at virtual address 00000008
pgd = ffffffc00165f000
[00000008] *pgd=000000000174f003, *pud=000000000174f003,
*pmd=0000000001750003, *pte=00e8000001751713
Internal error: Oops: 96000005 [#1] PREEMPT SMP
Modules linked in: uinput uvcvideo videobuf2_vmalloc cmac [ ... ]
CPU: 5 PID: 3353 Comm: kworker/5:3 Tainted: G B 4.4.52 #480
Hardware name: Google Kevin (DT)
Workqueue: events driver_set_config_work
task: ffffffc0c3690000 ti: ffffffc0ae9a8000 task.ti: ffffffc0ae9a8000
PC is at hub_port_init+0xc3c/0xd10
LR is at hub_port_init+0xc3c/0xd10
...
Call trace:
[<ffffffc0007fbbfc>] hub_port_init+0xc3c/0xd10
[<ffffffc0007fbe2c>] usb_reset_and_verify_device+0x15c/0x82c
[<ffffffc0007fc5e0>] usb_reset_device+0xe4/0x298
[<ffffffbffc0e3fcc>] rtl8152_probe+0x84/0x9b0 [r8152]
[<ffffffc00080ca8c>] usb_probe_interface+0x244/0x2f8
[<ffffffc000774a24>] driver_probe_device+0x180/0x3b4
[<ffffffc000774e48>] __device_attach_driver+0xb4/0xe0
[<ffffffc000772168>] bus_for_each_drv+0xb4/0xe4
[<ffffffc0007747ec>] __device_attach+0xd0/0x158
[<ffffffc000775080>] device_initial_probe+0x24/0x30
[<ffffffc0007739d4>] bus_probe_device+0x50/0xe4
[<ffffffc000770bd0>] device_add+0x414/0x738
[<ffffffc000809fe8>] usb_set_configuration+0x89c/0x914
[<ffffffc00080a120>] driver_set_config_work+0xc0/0xf0
[<ffffffc000249bb8>] process_one_work+0x390/0x6b8
[<ffffffc00024abcc>] worker_thread+0x480/0x610
[<ffffffc000251a80>] kthread+0x164/0x178
[<ffffffc0002045d0>] ret_from_fork+0x10/0x40
Since we don't know anything about LPM capabilities without BOS descriptor,
don't attempt to enable LPM if it is not available.
Fixes: 890dae8867 ("xhci: Enable LPM support only for hardwired ...")
Cc: stable <stable@vger.kernel.org>
Cc: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
EHCI controllers will have a companion controller. However, on platform
bus, there was difficult to bind them in previous code. So, this
patch adds helper functions to bind them using a "companion" property.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
a lot of embeded system SOC (e.g. freescale T2080) have both
PCI and USB modules. But USB module is controlled by registers directly,
it have no relationship with PCI module.
when say N here it will not build PCI related code in USB driver.
Signed-off-by: yuan linyu <Linyu.Yuan@alcatel-sbell.com.cn>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some USB 2.0 devices erroneously report millisecond values in
bInterval. The generic config code manages to catch most of them,
but in some cases it's not completely enough.
The case at stake here is a USB 2.0 braille device, which wants to
announce 10ms and thus sets bInterval to 10, but with the USB 2.0
computation that yields to 64ms. It happens that one can type fast
enough to reach this interval and get the device buffers overflown,
leading to problematic latencies. The generic config code does not
catch this case because the 64ms is considered a sane enough value.
This change thus adds a USB_QUIRK_LINEAR_FRAME_INTR_BINTERVAL quirk
to mark devices which actually report milliseconds in bInterval,
and marks Vario Ultra devices as needing it.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Update the .c files that depend on these APIs.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.
Create a trivial placeholder <linux/sched/signal.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fix typos and add the following to the scripts/spelling.txt:
an one||a one
I dropped the "an" before "one or more" in
drivers/net/ethernet/sfc/mcdi_pcol.h.
Link: http://lkml.kernel.org/r/1481573103-11329-6-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a quirk for WORLDE easykey.25 MIDI keyboard (idVendor=0218,
idProduct=0401). The device reports that it has config string
descriptor at index 3, but when the system selects the configuration
and tries to get the description, it returns a -EPROTO error,
the communication restarts and this keeps repeating over and over again.
Not requesting the string descriptor makes the device work correctly.
Relevant info from Wireshark:
[...]
CONFIGURATION DESCRIPTOR
bLength: 9
bDescriptorType: 0x02 (CONFIGURATION)
wTotalLength: 101
bNumInterfaces: 2
bConfigurationValue: 1
iConfiguration: 3
Configuration bmAttributes: 0xc0 SELF-POWERED NO REMOTE-WAKEUP
1... .... = Must be 1: Must be 1 for USB 1.1 and higher
.1.. .... = Self-Powered: This device is SELF-POWERED
..0. .... = Remote Wakeup: This device does NOT support remote wakeup
bMaxPower: 50 (100mA)
[...]
45 0.369104 host 2.38.0 USB 64 GET DESCRIPTOR Request STRING
[...]
URB setup
bmRequestType: 0x80
1... .... = Direction: Device-to-host
.00. .... = Type: Standard (0x00)
...0 0000 = Recipient: Device (0x00)
bRequest: GET DESCRIPTOR (6)
Descriptor Index: 0x03
bDescriptorType: 0x03
Language Id: English (United States) (0x0409)
wLength: 255
46 0.369255 2.38.0 host USB 64 GET DESCRIPTOR Response STRING[Malformed Packet]
[...]
Frame 46: 64 bytes on wire (512 bits), 64 bytes captured (512 bits) on interface 0
USB URB
[Source: 2.38.0]
[Destination: host]
URB id: 0xffff88021f62d480
URB type: URB_COMPLETE ('C')
URB transfer type: URB_CONTROL (0x02)
Endpoint: 0x80, Direction: IN
Device: 38
URB bus id: 2
Device setup request: not relevant ('-')
Data: present (0)
URB sec: 1484896277
URB usec: 455031
URB status: Protocol error (-EPROTO) (-71)
URB length [bytes]: 0
Data length [bytes]: 0
[Request in: 45]
[Time from request: 0.000151000 seconds]
Unused Setup Header
Interval: 0
Start frame: 0
Copy of Transfer Flags: 0x00000200
Number of ISO descriptors: 0
[Malformed Packet: USB]
[Expert Info (Error/Malformed): Malformed Packet (Exception occurred)]
[Malformed Packet (Exception occurred)]
[Severity level: Error]
[Group: Malformed]
Signed-off-by: Lukáš Lalinský <lukas@oxygene.sk>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On some platforms(e.g. rk3399 board), we can call hcd_add/remove
consecutively without calling usb_put_hcd/usb_create_hcd in between,
so hcd->flags can be stale.
If the HC dies due to whatever reason then without this patch we get
the below error on next hcd_add.
[173.296154] xhci-hcd xhci-hcd.2.auto: HC died; cleaning up
[173.296209] xhci-hcd xhci-hcd.2.auto: xHCI Host Controller
[173.296762] xhci-hcd xhci-hcd.2.auto: new USB bus registered, assigned bus number 6
[173.296931] usb usb6: We don't know the algorithms for LPM for this host, disabling LPM.
[173.297179] usb usb6: New USB device found, idVendor=1d6b, idProduct=0003
[173.297203] usb usb6: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[173.297222] usb usb6: Product: xHCI Host Controller
[173.297240] usb usb6: Manufacturer: Linux 4.4.21 xhci-hcd
[173.297257] usb usb6: SerialNumber: xhci-hcd.2.auto
[173.298680] hub 6-0:1.0: USB hub found
[173.298749] hub 6-0:1.0: 1 port detected
[173.299382] rockchip-dwc3 usb@fe800000: USB HOST connected
[173.395418] hub 5-0:1.0: activate --> -19
[173.603447] irq 228: nobody cared (try booting with the "irqpoll" option)
[173.603493] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.4.21 #9
[173.603513] Hardware name: Google Kevin (DT)
[173.603531] Call trace:
[173.603568] [<ffffffc0002087dc>] dump_backtrace+0x0/0x160
[173.603596] [<ffffffc00020895c>] show_stack+0x20/0x28
[173.603623] [<ffffffc0004b28a8>] dump_stack+0x90/0xb0
[173.603650] [<ffffffc00027347c>] __report_bad_irq+0x48/0xe8
[173.603674] [<ffffffc0002737cc>] note_interrupt+0x1e8/0x28c
[173.603698] [<ffffffc000270a38>] handle_irq_event_percpu+0x1d4/0x25c
[173.603722] [<ffffffc000270b0c>] handle_irq_event+0x4c/0x7c
[173.603748] [<ffffffc00027456c>] handle_fasteoi_irq+0xb4/0x124
[173.603777] [<ffffffc00026fe3c>] generic_handle_irq+0x30/0x44
[173.603804] [<ffffffc0002701a8>] __handle_domain_irq+0x90/0xbc
[173.603827] [<ffffffc0002006f4>] gic_handle_irq+0xcc/0x188
...
[173.604500] [<ffffffc000203700>] el1_irq+0x80/0xf8
[173.604530] [<ffffffc000261388>] cpu_startup_entry+0x38/0x3cc
[173.604558] [<ffffffc00090f7d8>] rest_init+0x8c/0x94
[173.604585] [<ffffffc000e009ac>] start_kernel+0x3d0/0x3fc
[173.604607] [<0000000000b16000>] 0xb16000
[173.604622] handlers:
[173.604648] [<ffffffc000642084>] usb_hcd_irq
[173.604673] Disabling IRQ #228
Signed-off-by: William wu <wulf@rock-chips.com>
Acked-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The commonly use of bottom halves are tasklet and workqueue. The big
difference between tasklet and workqueue is that the tasklet runs in
an interrupt context and the workqueue runs in a process context,
which means it can sleep if need be.
The comment for usb_control/interrupt/bulk_msg() functions note that do
not use this function within an interrupt context, like a 'bottom half'
handler. With this comment, it makes confuse about usage of these
functions.
To more clarify, remove 'bottom half' comment.
Signed-off-by: Jaejoong Kim <climbbb.kim@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Promote a variable keeping track of USB transfer memory usage to a
wider data type and allow for higher bandwidth transfers from a large
number of USB devices connected to a single host.
Signed-off-by: Mateusz Berezecki <mateuszb@fastmail.fm>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When checking a new device's descriptors, the USB core does not check
for duplicate endpoint addresses. This can cause a problem when the
sysfs files for those endpoints are created; trying to create multiple
files with the same name will provoke a WARNING:
WARNING: CPU: 2 PID: 865 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x8a/0xa0
sysfs: cannot create duplicate filename
'/devices/platform/dummy_hcd.0/usb2/2-1/2-1:64.0/ep_05'
Kernel panic - not syncing: panic_on_warn set ...
CPU: 2 PID: 865 Comm: kworker/2:1 Not tainted 4.9.0-rc7+ #34
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Workqueue: usb_hub_wq hub_event
ffff88006bee64c8 ffffffff81f96b8a ffffffff00000001 1ffff1000d7dcc2c
ffffed000d7dcc24 0000000000000001 0000000041b58ab3 ffffffff8598b510
ffffffff81f968f8 ffffffff850fee20 ffffffff85cff020 dffffc0000000000
Call Trace:
[< inline >] __dump_stack lib/dump_stack.c:15
[<ffffffff81f96b8a>] dump_stack+0x292/0x398 lib/dump_stack.c:51
[<ffffffff8168c88e>] panic+0x1cb/0x3a9 kernel/panic.c:179
[<ffffffff812b80b4>] __warn+0x1c4/0x1e0 kernel/panic.c:542
[<ffffffff812b8195>] warn_slowpath_fmt+0xc5/0x110 kernel/panic.c:565
[<ffffffff819e70ca>] sysfs_warn_dup+0x8a/0xa0 fs/sysfs/dir.c:30
[<ffffffff819e7308>] sysfs_create_dir_ns+0x178/0x1d0 fs/sysfs/dir.c:59
[< inline >] create_dir lib/kobject.c:71
[<ffffffff81fa1b07>] kobject_add_internal+0x227/0xa60 lib/kobject.c:229
[< inline >] kobject_add_varg lib/kobject.c:366
[<ffffffff81fa2479>] kobject_add+0x139/0x220 lib/kobject.c:411
[<ffffffff82737a63>] device_add+0x353/0x1660 drivers/base/core.c:1088
[<ffffffff82738d8d>] device_register+0x1d/0x20 drivers/base/core.c:1206
[<ffffffff82cb77d3>] usb_create_ep_devs+0x163/0x260 drivers/usb/core/endpoint.c:195
[<ffffffff82c9f27b>] create_intf_ep_devs+0x13b/0x200 drivers/usb/core/message.c:1030
[<ffffffff82ca39d3>] usb_set_configuration+0x1083/0x18d0 drivers/usb/core/message.c:1937
[<ffffffff82cc9e2e>] generic_probe+0x6e/0xe0 drivers/usb/core/generic.c:172
[<ffffffff82caa7fa>] usb_probe_device+0xaa/0xe0 drivers/usb/core/driver.c:263
This patch prevents the problem by checking for duplicate endpoint
addresses during enumeration and skipping any duplicates.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If CONFIG_PM=n:
drivers/usb/core/hub.c:107: warning: ‘hub_usb3_port_prepare_disable’ declared inline after being called
drivers/usb/core/hub.c:107: warning: previous declaration of ‘hub_usb3_port_prepare_disable’ was here
To fix this, move hub_port_disable() after
hub_usb3_port_prepare_disable(), and adjust forward declarations.
Fixes: 37be66767e ("usb: hub: Fix auto-remount of safely removed or ejected USB-3 devices")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On a system with a defective USB device connected to an USB hub,
an endless sequence of port connect events was observed. The sequence
of events as observed is as follows:
- Port reports connected event (port status=USB_PORT_STAT_CONNECTION).
- Event handler debounces port and resets it by calling hub_port_reset().
- hub_port_reset() calls hub_port_wait_reset() to wait for the reset
to complete.
- The reset completes, but USB_PORT_STAT_CONNECTION is not immediately
set in the port status register.
- hub_port_wait_reset() returns -ENOTCONN.
- Port initialization sequence is aborted.
- A few milliseconds later, the port again reports a connected event,
and the sequence repeats.
This continues either forever or, randomly, stops if the connection
is already re-established when the port status is read. It results in
a high rate of udev events. This in turn destabilizes userspace since
the above sequence holds the device mutex pretty much continuously
and prevents userspace from actually reading the device status.
To prevent the problem from happening, let's wait for the connection
to be re-established after a port reset. If the device was actually
disconnected, the code will still return an error, but it will do so
only after the long reset timeout.
Cc: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
One big merge this time with a total of 166 non-merge commits.
Most of the work, by far, is on dwc2 this time (68.2%) with dwc3 a far
second (22.5%). The remaining 9.3% are scattered on gadget drivers.
The most important changes for dwc2 are the peripheral side DMA support
implemented by Synopsys folks and support for the new IOT dwc2
compatible core from Synopsys.
In dwc3 land we have support for high-bandwidth, high-speed isochronous
endpoints and some non-critical fixes for large scatter lists.
Apart from these, we have our usual set of cleanups, non-critical fixes,
etc.
-----BEGIN PGP SIGNATURE-----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=5WN9
-----END PGP SIGNATURE-----
Merge tag 'usb-for-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-next
Felipe writes:
usb: patches for v4.10 merge window
One big merge this time with a total of 166 non-merge commits.
Most of the work, by far, is on dwc2 this time (68.2%) with dwc3 a far
second (22.5%). The remaining 9.3% are scattered on gadget drivers.
The most important changes for dwc2 are the peripheral side DMA support
implemented by Synopsys folks and support for the new IOT dwc2
compatible core from Synopsys.
In dwc3 land we have support for high-bandwidth, high-speed isochronous
endpoints and some non-critical fixes for large scatter lists.
Apart from these, we have our usual set of cleanups, non-critical fixes,
etc.
Since usb_endpoint_maxp now returns only lower 11 bits mult
calculation here isn't correct anymore and that breaks webcam
for me. Patch make use of usb_endpoint_maxp_mult instead of
direct calculation.
Fixes: abb621844f ("usb: ch9: make usb_endpoint_maxp() return
only packet size")
Signed-off-by: Mike Krinkin <krinkin.m.u@gmail.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
USB-3 does not have any link state that will avoid negotiating a connection
with a plugged-in cable but will signal the host when the cable is
unplugged.
For USB-3 we used to first set the link to Disabled, then to RxDdetect to
be able to detect cable connects or disconnects. But in RxDetect the
connected device is detected again and eventually enabled.
Instead set the link into U3 and disable remote wakeups for the device.
This is what Windows does, and what Alan Stern suggested.
Cc: stable@vger.kernel.org
Cc: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that usb_endpoint_maxp() only returns the lowest
11 bits from wMaxPacketSize, we can remove the &
operation from this driver.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Now that usb_endpoint_maxp() only returns the lowest
11 bits from wMaxPacketSize, we can remove the &
operation from this driver.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <linux-usb@vger.kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
We have introduced a helper to calculate multiplier
value from wMaxPacketSize. Start using it.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <linux-usb@vger.kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Some of the USB core files were missing explicit license information.
As all files in the kernel tree are implicitly licensed under the
GPLv2-only, be explicit in case someone get confused looking at
individual files by using the SPDX nomenclature.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Grub finds incorrect of_node path for devices behind usb hub.
Added devspec sysfs entry for devices behind usb hub so that
right of_node path is returned during grub sysfs walk for these
devices.
Signed-off-by: Vijay Kumar <vijay.ac.kumar@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull more vfs updates from Al Viro:
">rename2() work from Miklos + current_time() from Deepa"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs: Replace current_fs_time() with current_time()
fs: Replace CURRENT_TIME_SEC with current_time() for inode timestamps
fs: Replace CURRENT_TIME with current_time() for inode timestamps
fs: proc: Delete inode time initializations in proc_alloc_inode()
vfs: Add current_time() api
vfs: add note about i_op->rename changes to porting
fs: rename "rename2" i_op to "rename"
vfs: remove unused i_op->rename
fs: make remaining filesystems use .rename2
libfs: support RENAME_NOREPLACE in simple_rename()
fs: support RENAME_NOREPLACE for local filesystems
ncpfs: fix unused variable warning
CURRENT_TIME macro is not appropriate for filesystems as it
doesn't use the right granularity for filesystem timestamps.
Use current_time() instead.
CURRENT_TIME is also not y2038 safe.
This is also in preparation for the patch that transitions
vfs timestamps to use 64 bit time and hence make them
y2038 safe. As part of the effort current_time() will be
extended to do range checks. Hence, it is necessary for all
file system timestamps to use current_time(). Also,
current_time() will be transitioned along with vfs to be
y2038 safe.
Note that whenever a single call to current_time() is used
to change timestamps in different inodes, it is because they
share the same time granularity.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Felipe Balbi <balbi@kernel.org>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: David Sterba <dsterba@suse.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In USB20 specification, describes in chapter 9.4.5: The Remote Wakeup
field can be modified by the SetFeature() and ClearFeature() requests
using the DEVICE_REMOTE_WAKEUP feature selector.
In USB30 specification, also describes in chapter 9.4.5: The Function
Remote Wakeup field can be modified by the SetFeature() requests
using the FUNCTION_SUSPEND feature selector. In chapter 9.4.9 Set
Feature reference, it describes Function Remote Wake Enabled/Disabled
at suspend options by SET_FEATURE.
In USB30 specification only mentioned SetFeature(), so we need use
SET_FEATURE replace CLEAR_FEATURE to disable USB30 function remote
wakeup in suspend options.
Signed-off-by: Yonglong Wu <yonglong.wu@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit adds a new trigger responsible for turning on LED when USB
device gets connected to the selected USB port. This can can useful for
various home routers that have USB port(s) and a proper LED telling user
a device is connected.
The trigger gets its documentation file but basically it just requires
enabling it and selecting USB ports (e.g. echo 1 > ports/usb1-1).
There was a long discussion on design of this driver. Its current state
is a result of picking them most adjustable solution as others couldn't
handle all cases.
1) It wasn't possible for the driver to register separated trigger for
each USB port. Some physical USB ports are handled by more than one
controller and so by more than one USB port. E.g. USB 2.0 physical
port may be handled by OHCI's port and EHCI's port.
It's also not possible to assign more than 1 trigger to a single LED
and implementing such feature would be tricky due to syncing triggers
and sysfs conflicts with old triggers.
2) Another idea was to register trigger per USB hub. This wouldn't allow
handling devices with multiple USB LEDs and controllers (hubs)
controlling more than 1 physical port. It's common for hubs to have
few ports and each may have its own LED.
This final trigger is highly flexible. It allows selecting any USB ports
for any LED. It was also modified (comparing to the initial version) to
allow choosing ports rather than having user /guess/ proper names. It
was successfully tested on SmartRG SR400ac which has 3 USB LEDs,
2 physical ports and 3 controllers.
It was noted USB subsystem already has usb-gadget and usb-host triggers
but they are pretty trivial ones. They indicate activity only and can't
have ports specified.
In future it may be good idea to consider adding activity support to
usbport as well. This should allow switching to this more generic driver
and maybe marking old ones as obsolete.
This can be implemented with another sysfs file for setting mode. The
default mode wouldn't change so there won't be ABI breakage and so such
feature can be safely implemented later.
There was also an idea of supporting other devices (PCI, SDIO, etc.) but
as this driver already contains some USB specific code (and will get
more) these should be probably separated drivers (triggers).
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We get 1 warning when building kernel with W=1:
drivers/usb/core/hcd.c:2390:5: warning: no previous prototype for 'usb_bus_start_enum' [-Wmissing-prototypes]
In fact, these functions are declared in linux/usb/otg.h, so this patch
adds the missing header dependencies.
Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some full-speed mceusb infrared transceivers contain invalid endpoint
descriptors for their interrupt endpoints, with bInterval set to 0.
In the past they have worked out okay with the mceusb driver, because
the driver sets the bInterval field in the descriptor to 1,
overwriting whatever value may have been there before. However, this
approach was never sanctioned by the USB core, and in fact it does not
work with xHCI controllers, because they use the bInterval value that
was present when the configuration was installed.
Currently usbcore uses 32 ms as the default interval if the value in
the endpoint descriptor is invalid. It turns out that these IR
transceivers don't work properly unless the interval is set to 10 ms
or below. To work around this mceusb problem, this patch changes the
endpoint-descriptor parsing routine, making the default interval value
be 10 ms rather than 32 ms.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Wade Berrier <wberrier@gmail.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If dma_pfn_offset is not inherited correctly from the host controller,
it might result in sub-optimal configuration as bounce
buffer limit might be set to less than optimal level.
Consider the mass storage device case.
USB storage driver creates a scsi host for the mass storage interface in
drivers/usb/storage/usb.c
The scsi host parent device is nothing but the the USB interface device.
Now, __scsi_init_queue() calls scsi_calculate_bounce_limit() to find out
and set the block layer bounce limit.
scsi_calculate_bounce_limit() uses dma_max_pfn(host_dev) to get the
bounce_limit. host_dev is nothing but the device representing the
mass storage interface.
If that device doesn't have the right dma_pfn_offset, then dma_max_pfn()
is messed up and the bounce buffer limit is wrong.
e.g. On Keystone 2 systems, dma_max_pfn() is 0x87FFFF and dma_mask_pfn
is 0xFFFFF. Consider a mass storage use case: Without this patch,
usb scsi host device (usb-storage) will get a dma_pfn_offset of 0 resulting
in a dma_max_pfn() of 0xFFFFF within the scsi layer
(scsi_calculate_bounce_limit()).
This will result in bounce buffers being unnecessarily used.
Hint: On 32-bit ARM platforms dma_max_pfn() = dma_mask_pfn + dma_pfn_offset
Signed-off-by: Roger Quadros <rogerq@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
