usb: typec: altmodes: add typec_cable_ops to typec_altmode

Add typec_cable_ops struct for enter, exit, and vdm. The struct is added
to typec_altmode so port alt modes can have access to partner and cable
specific callbacks, and alt mode drivers can specify operations over SOP'
and SOP'' without modifying the existing API.

typec_port_register_cable_ops is added as a new symbol for port drivers
to use to register cable operations to their registered port alt modes.

Signed-off-by: RD Babiera <rdbabiera@google.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20240108191620.987785-15-rdbabiera@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: typec: bus: verify partner exists in typec_altmode_attention

Some usb hubs will negotiate DisplayPort Alt mode with the device
but will then negotiate a data role swap after entering the alt
mode. The data role swap causes the device to unregister all alt
modes, however the usb hub will still send Attention messages
even after failing to reregister the Alt Mode. type_altmode_attention
currently does not verify whether or not a device's altmode partner
exists, which results in a NULL pointer error when dereferencing
the typec_altmode and typec_altmode_ops belonging to the altmode
partner.

Verify the presence of a device's altmode partner before sending
the Attention message to the Alt Mode driver.

Fixes: 8a37d87d72f0 ("usb: typec: Bus type for alternate modes")
Cc: stable@vger.kernel.org
Signed-off-by: RD Babiera <rdbabiera@google.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230814180559.923475-1-rdbabiera@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: mark all struct bus_type as const

Now that the driver core can properly handle constant struct bus_type,
move all of the USB subsystem struct bus_type structures as const,
placing them into read-only memory which can not be modified at runtime.

Cc: Johan Hovold <johan@kernel.org>
Cc: Evan Green <evgreen@chromium.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: linux-usb@vger.kernel.org
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20230313182918.1312597-36-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

driver core: make struct bus_type.uevent() take a const *

The uevent() callback in struct bus_type should not be modifying the
device that is passed into it, so mark it as a const * and propagate the
function signature changes out into all relevant subsystems that use
this callback.

Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230111113018.459199-16-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: typec: Make bus switch code retimer-aware

Since ports can have retimers associated with them, update the Type-C
alternate mode bus code to also set retimer state when the switch state
is updated.

While we are here, make the typec_retimer_dev_type declaration in the
retimer.h file as extern, so that the header file can be successfully
included in the bus code without redeclaration compilation errors.

Signed-off-by: Prashant Malani <pmalani@chromium.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20230112221609.540754-4-pmalani@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: typec: Add wrapper for bus switch set code

Add a wrapper that calls the set() function for various switches
associated with a port altmode.

Right now, it just wraps the existing typec_mux_set() command,
but it can be expanded to include other switches in future patches.

No functional changes introduced by this patch.

Signed-off-by: Prashant Malani <pmalani@chromium.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20230112221609.540754-3-pmalani@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: typec: Check for ops->exit instead of ops->enter in altmode_exit

typec_altmode_exit checks if ops->enter is not NULL but then calls
ops->exit a few lines below. Fix that and check for the function
pointer it's about to call instead.

Fixes: 8a37d87d72f0 ("usb: typec: Bus type for alternate modes")
Signed-off-by: Sven Peter <sven@svenpeter.dev>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20221114165924.33487-1-sven@svenpeter.dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: typec: mux: Introduce indirection

Rather than directly exposing the implementation's representation of the
typec muxes to the controller/clients, introduce an indirection object.

This enables the introduction of turning this relationship into a
one-to-many in the following patch.

Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220422222351.1297276-5-bjorn.andersson@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

bus: Make remove callback return void

The driver core ignores the return value of this callback because there
is only little it can do when a device disappears.

This is the final bit of a long lasting cleanup quest where several
buses were converted to also return void from their remove callback.
Additionally some resource leaks were fixed that were caused by drivers
returning an error code in the expectation that the driver won't go
away.

With struct bus_type::remove returning void it's prevented that newly
implemented buses return an ignored error code and so don't anticipate
wrong expectations for driver authors.

Reviewed-by: Tom Rix <trix@redhat.com> (For fpga)
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com> (For drivers/s390 and drivers/vfio)
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> (For ARM, Amba and related parts)
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Chen-Yu Tsai <wens@csie.org> (for sunxi-rsb)
Acked-by: Pali Rohár <pali@kernel.org>
Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org> (for media)
Acked-by: Hans de Goede <hdegoede@redhat.com> (For drivers/platform)
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-By: Vinod Koul <vkoul@kernel.org>
Acked-by: Juergen Gross <jgross@suse.com> (For xen)
Acked-by: Lee Jones <lee.jones@linaro.org> (For mfd)
Acked-by: Johannes Thumshirn <jth@kernel.org> (For mcb)
Acked-by: Johan Hovold <johan@kernel.org>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> (For slimbus)
Acked-by: Kirti Wankhede <kwankhede@nvidia.com> (For vfio)
Acked-by: Maximilian Luz <luzmaximilian@gmail.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> (For ulpi and typec)
Acked-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com> (For ipack)
Acked-by: Geoff Levand <geoff@infradead.org> (For ps3)
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com> (For thunderbolt)
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> (For intel_th)
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net> (For pcmcia)
Acked-by: Rafael J. Wysocki <rafael@kernel.org> (For ACPI)
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org> (rpmsg and apr)
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> (For intel-ish-hid)
Acked-by: Dan Williams <dan.j.williams@intel.com> (For CXL, DAX, and NVDIMM)
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com> (For isa)
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (For firewire)
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> (For hid)
Acked-by: Thorsten Scherer <t.scherer@eckelmann.de> (For siox)
Acked-by: Sven Van Asbroeck <TheSven73@gmail.com> (For anybuss)
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> (For MMC)
Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Finn Thain <fthain@linux-m68k.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210713193522.1770306-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: typec: Organize the private headers properly

Adding a header file for each subsystem - the connector
class, alt mode bus and the class for the muxes.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20210401105847.13026-2-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: typec: altmode: Fix typec_altmode_get_partner sometimes returning an invalid pointer

Before this commit, typec_altmode_get_partner would return a
const struct typec_altmode * pointing to address 0x08 when
to_altmode(adev)->partner was NULL.

Add a check for to_altmode(adev)->partner being NULL to fix this.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=206365
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1785972
Fixes: 5f54a85db5df ("usb: typec: Make sure an alt mode exist before getting its partner")
Cc: stable@vger.kernel.org
Signed-off-by: Naoki Kiryu <naonaokiryu2@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20200422144345.43262-1-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: typec: altmode: Remove the notification chain

Using the generic notification chain is not reasonable with
the alternate modes because it would require dependencies
between the drivers of the components that need the
notifications, and the typec drivers.

There are no users for the alternate mode notifications, so
removing the chain and the API for it completely.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20200211112531.86510-6-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: typec: Give the mux drivers all the details regarding the port state

Passing all the details that the alternate mode drivers
provide to the mux drivers during mode changes.

The mux drivers will in practice need to be able to make
decisions on their own. It is not enough that they get only
the requested port state. With the Thunderbolt 3 alternate
mode for example the mux driver will need to consider also
the capabilities of the cable before configuring the mux.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20191230142611.24921-13-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: typec: Add parameter for the VDO to typec_altmode_enter()

Enter Mode Command may contain one VDO.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20191230142611.24921-3-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: typec: Block mode entry if the port has the mode disabled

Originally the port drivers were expected to check does the
connector have the mode enabled or disabled when the alt
mode drivers attempted to enter the mode, but since
typec_altmode_enter() puts the connector into USB Safe
State before calling the port driver, it really has to do
the check on its own, and before changing the state.
Otherwise the connector may be left in USB Safe State if the
port driver does not move it back to normal USB operation
when the mode is disabled.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20191230142611.24921-2-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: typec: fix non-kernel-doc comments

Use "/*" for non-kernel-doc comments instead of "/**", which is
intended to be used only for kernel-doc notation.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/88821011-2128-a8dd-68b8-c5ae8f43271f@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: typec: Make sure an alt mode exist before getting its partner

Adding check to typec_altmode_get_partner() to prevent
potential NULL pointer dereference.

Reported-by: Vladimir Yerilov <openmindead@gmail.com>
Fixes: ad74b8649bea ("usb: typec: ucsi: Preliminary support for alternate modes")
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb/typec: fix kernel-doc notation warning for typec_match_altmode

Fix kernel-doc warning for missing function parameter 'mode' description:

../drivers/usb/typec/bus.c:268: warning: Function parameter or member 'mode' not described in 'typec_match_altmode'

Also fix typos for same function documentation.

Fixes: 8a37d87d72f0 ("usb: typec: Bus type for alternate modes")

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: typec: fix dereference before null check on adev

Pointer adev is being dereferenced before it is being sanity
checked with a null pointer check, hence it is possible for
a null pointer dereference to occur. Fix this by dereferencing
adev only once it is null checked.

Detected by CoverityScan, CID#1471598 ("Dereference before null check")

Fixes: 8a37d87d72f0 ("usb: typec: Bus type for alternate modes")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: typec: Bus type for alternate modes

Introducing a simple bus for the alternate modes. Bus allows
binding drivers to the discovered alternate modes the
partners support.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>