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This is a regression introduced by 1373fefc6243 ("usb: typec: tcpm:
Allow slow charging loops to comply to pSnkStby")
When Source advertises Rp-default, tcpm would request 500mA when in
SINK_DISCOVERY, Type-C spec advises the sink to follow BC1.2 current
limits when Rp-default is advertised.
[12750.503381] Requesting mux state 1, usb-role 2, orientation 1
[12750.503837] state change SNK_ATTACHED -> SNK_STARTUP [rev3 NONE_AMS]
[12751.003891] state change SNK_STARTUP -> SNK_DISCOVERY
[12751.003900] Setting voltage/current limit 5000 mV 500 mA
This patch restores the behavior where the tcpm would request 0mA when
Rp-default is advertised by the source.
[ 73.174252] Requesting mux state 1, usb-role 2, orientation 1
[ 73.174749] state change SNK_ATTACHED -> SNK_STARTUP [rev3 NONE_AMS]
[ 73.674800] state change SNK_STARTUP -> SNK_DISCOVERY
[ 73.674808] Setting voltage/current limit 5000 mV 0 mA
During SNK_DISCOVERY, Cap the current limit to PD_P_SNK_STDBY_MW / 5 only
for slow_charger_loop case.
Fixes: 1373fefc6243 ("usb: typec: tcpm: Allow slow charging loops to comply to pSnkStby")
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>
Link: https://lore.kernel.org/r/20210510211756.3346954-1-badhri@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
One of AMD xhci controller require reset on resume.
Occasionally AMD xhci controller does not respond to
Stop endpoint command.
Once the issue happens controller goes into bad state
and in that case controller needs to be reset.
Cc: <stable@vger.kernel.org>
Signed-off-by: Sandeep Singh <sandeep.singh@amd.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20210512080816.866037-6-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On some devices (specifically the SC8180x based Surface Pro X with
QCOM04A6) HC halt / xhci_halt() times out during boot. Manually binding
the xhci-hcd driver at some point later does not exhibit this behavior.
To work around this, double XHCI_MAX_HALT_USEC, which also resolves this
issue.
Cc: <stable@vger.kernel.org>
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20210512080816.866037-5-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
'xhci_urb_enqueue()' is passed a 'mem_flags' argument, because "URBs may be
submitted in interrupt context" (see comment related to 'usb_submit_urb()'
in 'drivers/usb/core/urb.c')
So this flag should be used in all the calling chain.
Up to now, 'xhci_check_maxpacket()' which is only called from
'xhci_urb_enqueue()', uses GFP_KERNEL.
Be safe and pass the mem_flags to this function as well.
Fixes: ddba5cd0aeff ("xhci: Use command structures when queuing commands on the command ring")
Cc: <stable@vger.kernel.org>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20210512080816.866037-4-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 9ebf30007858 ("xhci: Fix halted endpoint at stop endpoint command
completion") in 5.12 changes how cancelled URBs are given back.
To cancel a URB xhci driver needs to stop the endpoint first.
To clear a halted endpoint xhci driver needs to reset the endpoint.
In rare cases when an endpoint halt (error) races with a endpoint stop we
need to clear the reset before removing, and giving back the cancelled URB.
The above change in 5.12 takes care of this, but it also relies on the
reset endpoint completion handler to give back the cancelled URBs.
There are cases when driver refuses to queue reset endpoint commands,
for example when a link suddenly goes to an inactive error state.
In this case the cancelled URB is never given back.
Fix this by giving back the URB in the stop endpoint if queuing a reset
endpoint command fails.
Fixes: 9ebf30007858 ("xhci: Fix halted endpoint at stop endpoint command completion")
CC: <stable@vger.kernel.org> # 5.12
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20210512080816.866037-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the same way as Intel Tiger Lake TCSS (Type-C Subsystem) the Alder Lake
TCSS xHCI needs to be runtime suspended whenever possible to allow the
TCSS hardware block to enter D3cold and thus save energy.
Cc: stable@vger.kernel.org
Signed-off-by: Abhijeet Rao <abhijeet.rao@intel.com>
Signed-off-by: Nikunj A. Dadhania <nikunj.dadhania@intel.com>
Signed-off-by: Azhar Shaikh <azhar.shaikh@intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20210512080816.866037-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
'ret' is known to be 0 here.
Initialize 'ret' with the expected error code before using it.
Fixes: 0990366bab3c ("usb: musb: Add support for MediaTek musb controller")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/69f514dc7134e3c917cad208e73cc650cb9e2bd6.1620159879.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Not_Supported Message is acceptable in VDM AMS. Redirect the VDM state
machine to VDM_STATE_DONE when receiving Not_Supported and finish the
VDM AMS.
Also, after the loop in vdm_state_machine_work, add more conditions of
VDM states to clear the vdm_sm_running flag because those are all
stopping states when leaving the loop.
In addition, finish the VDM AMS if the port partner responds BUSY.
Fixes: 8dea75e11380 ("usb: typec: tcpm: Protocol Error handling")
Fixes: 8d3a0578ad1a ("usb: typec: tcpm: Respond Wait if VDM state machine is running")
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Kyle Tso <kyletso@google.com>
Link: https://lore.kernel.org/r/20210507062300.1945009-3-kyletso@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In current design, DISCOVER_IDENTITY is queued to VDM state machine
immediately in Ready states and never retries if it fails in the AMS.
Move the process to a delayed work so that when it fails for some
reasons (e.g. Sink Tx No Go), it can be retried by queueing the work
again. Also fix a problem that the vdm_state is not set to a proper
state if it is blocked by Collision Avoidance mechanism.
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Kyle Tso <kyletso@google.com>
Link: https://lore.kernel.org/r/20210507062300.1945009-2-kyletso@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4dbc6a4ef06d ("usb: typec: ucsi: save power data objects
in PD mode") introduced retrieval of the PDOs when connected to a
PD-capable source. But only the first 4 PDOs are received since
that is the maximum number that can be fetched at a time given the
MESSAGE_IN length limitation (16 bytes). However, as per the PD spec
a connected source may advertise up to a maximum of 7 PDOs.
If such a source is connected it's possible the PPM could have
negotiated a power contract with one of the PDOs at index greater
than 4, and would be reflected in the request data object's (RDO)
object position field. This would result in an out-of-bounds access
when the rdo_index() is used to index into the src_pdos array in
ucsi_psy_get_voltage_now().
With the help of the UBSAN -fsanitize=array-bounds checker enabled
this exact issue is revealed when connecting to a PD source adapter
that advertise 5 PDOs and the PPM enters a contract having selected
the 5th one.
[ 151.545106][ T70] Unexpected kernel BRK exception at EL1
[ 151.545112][ T70] Internal error: BRK handler: f2005512 [#1] PREEMPT SMP
...
[ 151.545499][ T70] pc : ucsi_psy_get_prop+0x208/0x20c
[ 151.545507][ T70] lr : power_supply_show_property+0xc0/0x328
...
[ 151.545542][ T70] Call trace:
[ 151.545544][ T70] ucsi_psy_get_prop+0x208/0x20c
[ 151.545546][ T70] power_supply_uevent+0x1a4/0x2f0
[ 151.545550][ T70] dev_uevent+0x200/0x384
[ 151.545555][ T70] kobject_uevent_env+0x1d4/0x7e8
[ 151.545557][ T70] power_supply_changed_work+0x174/0x31c
[ 151.545562][ T70] process_one_work+0x244/0x6f0
[ 151.545564][ T70] worker_thread+0x3e0/0xa64
We can resolve this by instead retrieving and storing up to the
maximum of 7 PDOs in the con->src_pdos array. This would involve
two calls to the GET_PDOS command.
Fixes: 992a60ed0d5e ("usb: typec: ucsi: register with power_supply class")
Fixes: 4dbc6a4ef06d ("usb: typec: ucsi: save power data objects in PD mode")
Cc: stable@vger.kernel.org
Reported-and-tested-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Jack Pham <jackp@codeaurora.org>
Link: https://lore.kernel.org/r/20210503074611.30973-1-jackp@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
'retval' is known to be -ENODEV here.
This is a hard-coded default error code which is not useful in the error
message. Moreover, another error message is printed at the end of the
error handling path. The corresponding error code (-ENOMEM) is more
informative.
So remove simplify the first error message.
While at it, also remove the useless initialization of 'retval'.
Fixes: 7d50195f6c50 ("usb: host: Faraday fotg210-hcd driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/94531bcff98e46d4f9c20183a90b7f47f699126c.1620333419.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Original path does not exists, so changed to
"Documentation/ABI/testing/configfs-usb-gadget"
Signed-off-by: Wei Ming Chen <jj251510319013@gmail.com>
Link: https://lore.kernel.org/r/20210506122020.7117-1-jj251510319013@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When extcon is used in combination with dwc3, it is assumed that the dwc3
registers are untouched and as such are only configured if VBUS is valid
or ID is tied to ground.
In case VBUS is not valid or ID is floating, the registers are not
configured as such during driver initialization, causing a wrong
default state during boot.
If the registers are not in a default state, because they are for
instance touched by a boot loader, this can cause for a kernel error.
Signed-off-by: Marcel Hamer <marcel@solidxs.se>
Link: https://lore.kernel.org/r/20210427122118.1948340-1-marcel@solidxs.se
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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