Re: [PATCH v5 1/2] iio: accel: bmc150: Duplicate ACPI entries

[Jonathan Cameron <jic23@kernel.org>]

On Thu, 15 Feb 2024 10:24:25 -0800
Jonathan LoBue <jlobue10@gmail.com> wrote:

> This patch adds a description of the duplicate ACPI identifier issue
> between devices using bmc150 and bmi323.
Title of patch doesn't reflect what is going on.

If there are no other changes needed I can tweak that whilst applying
to

iio: accel: bmc150: Document duplicate ACPI entries with bmi323 driver

> 
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> Co-developed-by: Luke D. Jones <luke@ljones.dev>
> Signed-off-by: Luke D. Jones <luke@ljones.dev>
> Co-developed-by: Denis Benato <benato.denis96@gmail.com>
> Signed-off-by: Denis Benato <benato.denis96@gmail.com>
> Co-developed-by: Antheas Kapenekakis <lkml@antheas.dev>
> Signed-off-by: Antheas Kapenekakis <lkml@antheas.dev>
> Signed-off-by: Jonathan LoBue <jlobue10@gmail.com>
> ---
>  drivers/iio/accel/bmc150-accel-i2c.c | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
> 
> diff --git a/drivers/iio/accel/bmc150-accel-i2c.c b/drivers/iio/accel/bmc150-accel-i2c.c
> index ee1ba134ad42..353271e23235 100644
> --- a/drivers/iio/accel/bmc150-accel-i2c.c
> +++ b/drivers/iio/accel/bmc150-accel-i2c.c
> @@ -224,6 +224,19 @@ static const struct acpi_device_id bmc150_accel_acpi_match[] = {
>  	{"BMA250E"},
>  	{"BMC150A"},
>  	{"BMI055A"},
> +	/*
> + 	 * The "BOSC0200" identifier used here is not unique to devices using
> + 	 * bmc150. The same "BOSC0200" identifier is found in the ACPI tables of
> + 	 * the ASUS ROG ALLY and Ayaneo AIR Plus which both use a Bosch BMI323
> + 	 * chip. This creates a conflict with duplicate ACPI identifiers which
> + 	 * multiple drivers want to use. Fortunately, when the bmc150 driver
> + 	 * starts to load on the ASUS ROG ALLY, the chip ID check portion fails
> + 	 * (correctly) because the chip IDs received (via i2c) are unique between
> + 	 * bmc150 and bmi323 and a dmesg output similar to this:
> + 	 * "bmc150_accel_i2c i2c-BOSC0200:00: Invalid chip 0" can be seen.
> + 	 * This allows the bmi323 driver to take over for ASUS ROG ALLY, and
> + 	 * other devices using the bmi323 chip.
> + 	 */
>  	{"BOSC0200"},
>  	{"BSBA0150"},
>  	{"DUAL250E"},