Re: [PATCH v2 0/2] ChromeOS Embedded controller hwmon driver

From: Mario Limonciello
Date: Tue May 07 2024 - 15:04:05 EST


On 5/7/2024 11:29, Thomas Weißschuh wrote:
Add a hwmon driver that reports fan and temperature readings from the
ChromeOS Embedded controller.

There was an earlier effort in 2017 to add such a driver [0], but there
was no followup after v1.
The new driver is complete reimplementation based on newer APIs and with
more features (temp sensor names).

It only works on LPC-connected ECs, as only those implement direct
memory-map access.
For other busses the data would need to be read with a command.
Adding some helpers was discussed in the previous patchset [1].

The EC protocols also support reading and writing fan curves but that is
not implemented.

Tested on a Framework 13 AMD, Firmware 3.05.

[0] https://lore.kernel.org/all/1491602410-31518-1-git-send-email-moritz.fischer@xxxxxxxxx/
[1] https://lore.kernel.org/all/ac61bfca-bfa0-143b-c9ca-365b8026ce8d@xxxxxxxxxxxx/

Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
---
Changes in v2:
- drop unnecessary range checks (Guenter)
- only validate thermal_version during probing
- reorder some variable declarations
- validate thermal_version directly in cros_ec_hwmon_probe (Mario)
- drop return value from probe_temp_sensors as it can't fail anymore
- fail with -ENODEV if cmd_readmem is missing to avoid spurious warnings
- Link to v1: https://lore.kernel.org/r/20240507-cros_ec-hwmon-v1-0-2c47c5ce8e85@xxxxxxxxxxxxxx

---
Thomas Weißschuh (2):
hwmon: add ChromeOS EC driver
mfd: cros_ec: Register hardware monitoring subdevice

Documentation/hwmon/cros_ec_hwmon.rst | 26 ++++
Documentation/hwmon/index.rst | 1 +
MAINTAINERS | 8 +
drivers/hwmon/Kconfig | 11 ++
drivers/hwmon/Makefile | 1 +
drivers/hwmon/cros_ec_hwmon.c | 269 ++++++++++++++++++++++++++++++++++
drivers/mfd/cros_ec_dev.c | 1 +
7 files changed, 317 insertions(+)
---
base-commit: 2fbe479c0024e1c6b992184a799055e19932aa48
change-id: 20240506-cros_ec-hwmon-24634b07cf6f

Best regards,

That was fast! The series looks good to me, thanks.

Reviewed-by: Mario Limonciello <mario.limonciello@xxxxxxx>