[PATCH 0/3] Add support for Battery Status AMS

[Amit Sunil Dhamne via B4 Relay <devnull+amitsd.google.com@kernel.org>]

PD 3.1 v1.8 Spec necessitates a response to Get_Battery_Status request
from the port partner (see "6.13.2 Applicability of Data Message").
This patchset adds support to get all the battery type power supplies
and query them to report the telemetry required to build a Battery
Status Message. Right now, this submission assumes all the battery type
power supplies that exist in the system are fixed (meaning cannot be hot
swapped).

Previously, I had sent a patch series [1]. However there were some
concerns. Broadly:
  * No client drivers
  * Duplicating dt properties
To address the above issues, we now have Fuel Gauge and Charger drivers.
Also, I have rectified my approach to fetch information about batteries
from the power supply core.

While, the original patch series [1] added support for Battery Caps as
well, this patch series only adds support for Battery Status. Therefore,
I am sending it as a new series while incorporating relevant feedback.

[1] https://lore.kernel.org/all/20250507-batt_ops-v2-0-8d06130bffe6@google.com/

Patches in series:
[A] "power: supply: core: Add power_supply_get_battery_all()"
[B] "usb: typec: tcpm: Add support for Battery Status response message"
[C] "power: supply: max17042: add handler for energy_now property"

Technical dependency of patches:
[C] is independent and can be applied in any order.
[B] depends on [A] due to `power_supply_get_battery_all` symbol.

Signed-off-by: Amit Sunil Dhamne <amitsd@google.com>
---
Amit Sunil Dhamne (3):
      power: Add power_supply_get_battery_all() to fetch battery psy handles
      usb: typec: tcpm: Add support for Battery Status response message
      power: supply: max17042: add handler for energy_now property

 drivers/power/supply/max17042_battery.c  |  60 ++++++++++---
 drivers/power/supply/power_supply_core.c | 122 +++++++++++++++++++++++++++
 drivers/usb/typec/tcpm/tcpm.c            | 140 ++++++++++++++++++++++++++++++-
 include/linux/power_supply.h             |   9 ++
 include/linux/usb/pd.h                   |  29 +++++++
 5 files changed, 344 insertions(+), 16 deletions(-)
---
base-commit: 57b8e2d666a31fa201432d58f5fe3469a0dd83ba
change-id: 20260501-batt-status-16b6761c0bb1

Best regards,
-- 
Amit Sunil Dhamne <amitsd@google.com>