Badhri Jagan Sridharan
bb7905681c
commitfbcd13df1eupstream. Stub from the spec: "4.5.2.2.4.2 Exiting from AttachWait.SNK State A Sink shall transition to Unattached.SNK when the state of both the CC1 and CC2 pins is SNK.Open for at least tPDDebounce. A DRP shall transition to Unattached.SRC when the state of both the CC1 and CC2 pins is SNK.Open for at least tPDDebounce." This change makes TCPM to wait in SNK_DEBOUNCED state until CC1 and CC2 pins is SNK.Open for at least tPDDebounce. Previously, TCPM resets the port if vbus is not present in PD_T_PS_SOURCE_ON. This causes TCPM to loop continuously when connected to a faulty power source that does not present vbus. Waiting in SNK_DEBOUNCED also ensures that TCPM is adherant to "4.5.2.2.4.2 Exiting from AttachWait.SNK State" requirements. [ 6169.280751] CC1: 0 -> 0, CC2: 0 -> 5 [state TOGGLING, polarity 0, connected] [ 6169.280759] state change TOGGLING -> SNK_ATTACH_WAIT [rev2 NONE_AMS] [ 6169.280771] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev2 NONE_AMS] [ 6169.282427] CC1: 0 -> 0, CC2: 5 -> 5 [state SNK_ATTACH_WAIT, polarity 0, connected] [ 6169.450825] state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED [delayed 170 ms] [ 6169.450834] pending state change SNK_DEBOUNCED -> PORT_RESET @ 480 ms [rev2 NONE_AMS] [ 6169.930892] state change SNK_DEBOUNCED -> PORT_RESET [delayed 480 ms] [ 6169.931296] disable vbus discharge ret:0 [ 6169.931301] Setting usb_comm capable false [ 6169.932783] Setting voltage/current limit 0 mV 0 mA [ 6169.932802] polarity 0 [ 6169.933706] Requesting mux state 0, usb-role 0, orientation 0 [ 6169.936689] cc:=0 [ 6169.936812] pending state change PORT_RESET -> PORT_RESET_WAIT_OFF @ 100 ms [rev2 NONE_AMS] [ 6169.937157] CC1: 0 -> 0, CC2: 5 -> 0 [state PORT_RESET, polarity 0, disconnected] [ 6170.036880] state change PORT_RESET -> PORT_RESET_WAIT_OFF [delayed 100 ms] [ 6170.036890] state change PORT_RESET_WAIT_OFF -> SNK_UNATTACHED [rev2 NONE_AMS] [ 6170.036896] Start toggling [ 6170.041412] CC1: 0 -> 0, CC2: 0 -> 0 [state TOGGLING, polarity 0, disconnected] [ 6170.042973] CC1: 0 -> 0, CC2: 0 -> 5 [state TOGGLING, polarity 0, connected] [ 6170.042976] state change TOGGLING -> SNK_ATTACH_WAIT [rev2 NONE_AMS] [ 6170.042981] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev2 NONE_AMS] [ 6170.213014] state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED [delayed 170 ms] [ 6170.213019] pending state change SNK_DEBOUNCED -> PORT_RESET @ 480 ms [rev2 NONE_AMS] [ 6170.693068] state change SNK_DEBOUNCED -> PORT_RESET [delayed 480 ms] [ 6170.693304] disable vbus discharge ret:0 [ 6170.693308] Setting usb_comm capable false [ 6170.695193] Setting voltage/current limit 0 mV 0 mA [ 6170.695210] polarity 0 [ 6170.695990] Requesting mux state 0, usb-role 0, orientation 0 [ 6170.701896] cc:=0 [ 6170.702181] pending state change PORT_RESET -> PORT_RESET_WAIT_OFF @ 100 ms [rev2 NONE_AMS] [ 6170.703343] CC1: 0 -> 0, CC2: 5 -> 0 [state PORT_RESET, polarity 0, disconnected] Fixes:f0690a25a1("staging: typec: USB Type-C Port Manager (tcpm)") Cc: stable@vger.kernel.org Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Badhri Jagan Sridharan <badhri@google.com> Link: https://lore.kernel.org/r/20211130001825.3142830-1-badhri@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To understand all the Linux-USB framework, you'll use these resources:
* This source code. This is necessarily an evolving work, and
includes kerneldoc that should help you get a current overview.
("make pdfdocs", and then look at "usb.pdf" for host side and
"gadget.pdf" for peripheral side.) Also, Documentation/usb has
more information.
* The USB 2.0 specification (from www.usb.org), with supplements
such as those for USB OTG and the various device classes.
The USB specification has a good overview chapter, and USB
peripherals conform to the widely known "Chapter 9".
* Chip specifications for USB controllers. Examples include
host controllers (on PCs, servers, and more); peripheral
controllers (in devices with Linux firmware, like printers or
cell phones); and hard-wired peripherals like Ethernet adapters.
* Specifications for other protocols implemented by USB peripheral
functions. Some are vendor-specific; others are vendor-neutral
but just standardized outside of the www.usb.org team.
Here is a list of what each subdirectory here is, and what is contained in
them.
core/ - This is for the core USB host code, including the
usbfs files and the hub class driver ("hub_wq").
host/ - This is for USB host controller drivers. This
includes UHCI, OHCI, EHCI, and others that might
be used with more specialized "embedded" systems.
gadget/ - This is for USB peripheral controller drivers and
the various gadget drivers which talk to them.
Individual USB driver directories. A new driver should be added to the
first subdirectory in the list below that it fits into.
image/ - This is for still image drivers, like scanners or
digital cameras.
../input/ - This is for any driver that uses the input subsystem,
like keyboard, mice, touchscreens, tablets, etc.
../media/ - This is for multimedia drivers, like video cameras,
radios, and any other drivers that talk to the v4l
subsystem.
../net/ - This is for network drivers.
serial/ - This is for USB to serial drivers.
storage/ - This is for USB mass-storage drivers.
class/ - This is for all USB device drivers that do not fit
into any of the above categories, and work for a range
of USB Class specified devices.
misc/ - This is for all USB device drivers that do not fit
into any of the above categories.