Now that Kees Cook has added a definition for HCS_N_PORTS_MAX in
commit 72dd184323 ("USB: EHCI: Add register array bounds to HCS
ports"), the code in ehci_hub_control() which sanitizes port index
values can be improved a little.
The idea behind this change is that it prevents a possible
out-of-bounds pointer computation, which the compiler might be able to
detect since the port_status[] array now has a fixed length rather
than a variable length.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20211002190217.GA537967@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The commit 217504a055 ("usb: typec: ucsi: Work around PPM
losing change information") had solved this issue
previously, but in a really complex manner. The core issue
is that on some platforms the EC firmware does not interrupt
the driver on unplug event in some cases, mainly when the
cable is unplugged immediately after the plug-in.
From now on handling that problem by simply re-checking new
connections.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20210920142419.54493-8-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
UCSI does not tell the driver explicitly when the firmware
(PPM in UCSI lingo) has actually detected the partner
alternate modes, there is no specific change event for that.
That's why they have to be checked with any notification
that informs that PD contract with that partner has been
achieved.
Previously the alternate modes were checked always when the
firmware (PPM) informed that something with the partner had
changed, but on some platforms the EC firmware does not
generate separate events for generic partner changes at all.
On those platforms the EC firmware notifies the driver only
about connections, or separately about the PD contract if it
was not achieved soon enough after the initial connection
event.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20210920142419.54493-6-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The "poll worker" that is introduced here is first used for
checking partner alternate modes, but it can later be used
for any partner task that requires a separate job to be
scheduled to the connector specific workqueues.
The mechanism allows the partner device specific tasks to be
polling tasks and also delayed tasks if necessary.
By polling the partner alternate modes with this mechanism
the long command completion timeout value can be reduced
back to normal. The long command completion timeout was only
used to work around a problem on some platforms where the EC
firmware (PPM) didn't return BUSY even when it should with
the alt mode commands.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20210920142419.54493-4-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The USB2.0 spec chapter 11.24.2.13 says that the USB port which is going
under test needs to be put in suspend state before sending the test
command. Many hubs, don't enforce this precondition and they work fine
without this step. But there are some "special" hubs, which requires to
disable the port power before sending the test command.
Because the USB spec mention that the port should be suspended, also
do this step before sending the test command. This could rise the
problem with other hubs which are not compliant with the spec and the
test command will not work if the port is suspend. If such hubs are
found, a similar workaround like the disable part could be implemented
to skip the suspend port command.
Signed-off-by: Razvan Heghedus <heghedus.razvan@gmail.com>
Link: https://lore.kernel.org/r/20210915121615.3790-1-heghedus.razvan@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Chunfeng Yun
Alan Stern
Zhiwei Yang
Gustavo A. R. Silva
Dmitry Osipenko
Cai Huoqing
Sven Peter
Heikki Krogerus
Xu Yang
Razvan Heghedus