[0/3] Introduce new driver cros-ec-charge-state

Message

Sung-Chi Li Nov. 18, 2024, 9:33 a.m. UTC

There is a battery charger IC connect to the ChromeOS Embedded
Controller (EC) if that device is configured to work with batteries, and
EC exposed the application processor with a set of control to limit the
overall current used for charging and current flow into the system.

We have seen that the battery charger is one of major thermal budget
consumer on the device. As such, it would be great that we can limit the
current running through the battery charger IC, and reserve thermal
budget for application processor to have more room running in higher
frequencies.

There are some existing drivers that can limit the current flow into the
system, but they either require certain features (e.g., needing ACPI
supports for cros_charge-control.c, which is only available on x86
system), and these current limiting mechanisms are achieved via indirect
configurations (e.g., cros_usbpd-charger.c via setting certain USB PD
charging profiles). As such, I introduced a new driver that can directly
manipulate the battery charging current and the system input current.

Signed-off-by: Sung-Chi, Li
---
Sung-Chi, Li (3):
      platform/chrome: cros_ec_charge_state: add new driver to control charge
      dt-bindings: chrome: add new binding google,cros-ec-chrage-state
      mfd: cros_ec: Add charge state control cell

 .../bindings/chrome/google,cros-charge-state.yaml  |  62 ++++++
 .../devicetree/bindings/mfd/google,cros-ec.yaml    |   4 +
 drivers/mfd/cros_ec_dev.c                          |   9 +
 drivers/platform/chrome/Kconfig                    |  11 ++
 drivers/platform/chrome/Makefile                   |   1 +
 drivers/platform/chrome/cros_ec_charge_state.c     | 215 +++++++++++++++++++++
 6 files changed, 302 insertions(+)
---
base-commit: 744cf71b8bdfcdd77aaf58395e068b7457634b2c
change-id: 20241118-add_charger_state-8c0d6e9a5e45

Best regards,