platform/chrome: cros_usbpd_notify: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230927081040.2198742-10-u.kleine-koenig@pengutronix.de
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>

platform/chrome: cros_usbpd_notify: Fix error handling in cros_usbpd_notify_init()

The following WARNING message was given when rmmod cros_usbpd_notify:

Unexpected driver unregister!
WARNING: CPU: 0 PID: 253 at drivers/base/driver.c:270 driver_unregister+0x8a/0xb0
Modules linked in: cros_usbpd_notify(-)
CPU: 0 PID: 253 Comm: rmmod Not tainted 6.1.0-rc3 #24
...
Call Trace:
<TASK>
cros_usbpd_notify_exit+0x11/0x1e [cros_usbpd_notify]
__x64_sys_delete_module+0x3c7/0x570
? __ia32_sys_delete_module+0x570/0x570
? lock_is_held_type+0xe3/0x140
? syscall_enter_from_user_mode+0x17/0x50
? rcu_read_lock_sched_held+0xa0/0xd0
? syscall_enter_from_user_mode+0x1c/0x50
do_syscall_64+0x37/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f333fe9b1b7

The reason is that the cros_usbpd_notify_init() does not check the return
value of platform_driver_register(), and the cros_usbpd_notify can
install successfully even if platform_driver_register() failed.

Fix by checking the return value of platform_driver_register() and
unregister cros_usbpd_notify_plat_driver when it failed.

Fixes: ec2daf6e33f9 ("platform: chrome: Add cros-usbpd-notify driver")
Signed-off-by: Yuan Can <yuancan@huawei.com>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Link: https://lore.kernel.org/r/20221117080823.77549-1-yuancan@huawei.com
Signed-off-by: Prashant Malani <pmalani@chromium.org>

platform/chrome: cros_ec_proto: Rename cros_ec_command function

cros_ec_command() is the name of a function as well as a struct, as such
it can confuse indexing tools (like ctags). Avoid this by renaming it to
cros_ec_cmd(). Update all the callsites to use the new name.

This patch is a find-and-replace, so should not introduce any functional
changes.

Suggested-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Prashant Malani <pmalani@chromium.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://lore.kernel.org/r/20220606201825.763788-3-pmalani@chromium.org

platform/chrome: cros_ec_proto: Add version for ec_command

Add a version parameter to cros_ec_command() for callers that may want
to specify which version of the host command they would like to use.

Signed-off-by: Prashant Malani <pmalani@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Link: https://lore.kernel.org/r/20210930022403.3358070-5-pmalani@chromium.org

platform/chrome: cros_ec_proto: Make data pointers void

Convert the input and output data pointers for cros_ec_command() to
void pointers so that the callers don't have to cast their custom
structs to uint8_t *.

Signed-off-by: Prashant Malani <pmalani@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Link: https://lore.kernel.org/r/20210930022403.3358070-4-pmalani@chromium.org

platform/chrome: cros_usbpd_notify: Move ec_command()

cros_ec_command() can be used by other modules too. So, move it to a
common location and export it.

This patch does not introduce any functional changes.

Signed-off-by: Prashant Malani <pmalani@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Link: https://lore.kernel.org/r/20210930022403.3358070-3-pmalani@chromium.org

platform/chrome: cros_usbpd_notify: Rename cros_ec_pd_command()

Rename cros_ec_pd_command()_to cros_ec_command() since it can be used
for sending any host command, and not just PD related ones.

This patch does not introduce any functional changes.

Signed-off-by: Prashant Malani <pmalani@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Link: https://lore.kernel.org/r/20210930022403.3358070-2-pmalani@chromium.org

platform/chrome: cros_usbpd_notify: Listen to EC_HOST_EVENT_USB_MUX host event

On system that use ACPI, cros_usbpd_notify gets notifications of USB MUX
host event same as PD host events [1]. But currently on system that use
DT, the driver only listen on EC_HOST_EVENT_PD_MCU.

Add EC_HOST_EVENT_USB_MUX to the list of host events, so we have same
behavior on all platforms.

[1]: https://chromium.googlesource.com/chromiumos/third_party/coreboot/+/refs/heads/chromeos-2016.05/src/ec/google/chromeec/acpi/ec.asl#382

Signed-off-by: Pi-Hsun Shih <pihsun@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Link: https://lore.kernel.org/r/20210414064524.2450908-1-pihsun@chromium.org

platform/chrome: cros_usbpd_notify: Pull PD_HOST_EVENT status

Read the PD host even status from the EC and send that to the notifier
listeners, for more fine-grained event information.

Signed-off-by: Prashant Malani <pmalani@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Benson Leung <bleung@chromium.org>

platform/chrome: cros_usbpd_notify: Amend ACPI driver to plat

Convert the ACPI driver into the equivalent platform driver, with the
same ACPI match table as before. This allows the device driver to access
the parent platform EC device and its cros_ec_device struct, which will
be required to communicate with the EC to pull PD Host event information
from it.

Also change the ACPI driver name to "cros-usbpd-notify-acpi" so that
there is no confusion between it and the "regular" platform driver on
platforms that have both CONFIG_ACPI and CONFIG_OF enabled.

Signed-off-by: Prashant Malani <pmalani@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Benson Leung <bleung@chromium.org>

platform/chrome: cros_usbpd_notify: Add driver data struct

Introduce a device driver data structure, cros_usbpd_notify_data, in
which we can store the notifier block object and pointers to the struct
cros_ec_device and struct device objects.

This will make it more convenient to access these pointers when
executing both platform and ACPI callbacks.

Signed-off-by: Prashant Malani <pmalani@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Benson Leung <bleung@chromium.org>

platform/chrome: cros_usbpd_notify: Fix cros-usbpd-notify notifier

cros-usbpd-notify notifier was returning NOTIFY_BAD when no host event
was available in the MKBP message.
But MKBP messages are used to transmit other information, so return
NOTIFY_DONE instead, to allow other notifier to be called.

Fixes: ec2daf6e33f9f ("platform: chrome: Add cros-usbpd-notify driver")
Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

platform: chrome: Add cros-usbpd-notify driver

ChromiumOS uses ACPI device with HID "GOOG0003" for power delivery
related events. The existing cros-usbpd-charger driver relies on these
events without ever actually receiving them on ACPI platforms. This is
because in the ChromeOS kernel trees, the GOOG0003 device is owned by an
ACPI driver that offers firmware updates to USB-C chargers.

Introduce a new platform driver under cros-ec, the ChromeOS embedded
controller, that handles these PD events and dispatches them
appropriately over a notifier chain to all drivers that use them.

On platforms that don't have the ACPI device defined, the driver gets
instantiated for ECs which support the EC_FEATURE_USB_PD feature bit,
and the notification events will get delivered using the MKBP event
handling mechanism.

Co-Developed-by: Prashant Malani <pmalani@chromium.org>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Jon Flatley <jflat@chromium.org>
Signed-off-by: Prashant Malani <pmalani@chromium.org>
Acked-By: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Benson Leung <bleung@chromium.org>