[PATCH v5 2/2] iio: imu: st_lsm6dsx: Add ACPI ID SMOCF05 for LSM6DS3TR-C

[Jared Wuerzburger]

From: Samuel Dionne-Riel <samuel@xxxxxxxxxxxxxxx>

The Minisforum V3 and V3 SE tablets declare their ST LSM6DS3TR-C IMU in
the DSDT with the hardware ID SMOCF05 instead of SMO8B30, so the driver
never binds and the accelerometer and gyroscope are missing. The
Windows driver (version 1.0.4.3) binds the LSM6DS3TR-C to both IDs.

The device has two I2C resources for the same address; the I2C core
uses the first one.

The vendor-specific SLA0/SLG0 matrix methods in the DSDT are not parsed,
because SLA0 is not usable as a mount matrix as it is. Its X and Y signs
are right, but it also negates Z. It follows the Windows sensor
convention, which reports Z = -1g with the screen facing up, while
iio-sensor-proxy uses the same X and Y signs but expects Z = +1g in that
posture. Applied as a mount matrix, SLA0 gives correct screen rotation,
but iio-sensor-proxy reports the tilt inverted. The actual mounting is a
plain 180 degree rotation about Z (-1 0 0; 0 -1 0; 0 0 1), with which
orientation and tilt are both right. As for SMOCF00, the matrix is
therefore provided by the systemd hwdb instead.

Tested on:
 - V3 SE (Ryzen 7 7735U, BIOS 1.03) with this change.
 - V3 (Ryzen 7 8840U, BIOS 1.06), kernel 7.2.7, with this change and
   the stock firmware tables. The driver binds to i2c-SMOCF05:00, the
   WHO_AM_I check passes (0x6a), and both lsm6ds3tr-c_accel and
   lsm6ds3tr-c_gyro are registered. Screen auto-rotation and tilt work
   with iio-sensor-proxy and the matrix above (checked with the device
   renamed to SMO8B30 via a DSDT override, i.e. the same
   ST_LSM6DS3TRC_ID driver data).

Closes: https://github.com/mudkipme/awesome-minisforum-v3/issues/2
Signed-off-by: Samuel Dionne-Riel <samuel@xxxxxxxxxxxxxxx>
[Jared Wuerzburger: rewrote the changelog with test results and the
 mount matrix rationale, converted the entry to C99 initializers,
 dropped the mount matrix patch]
Assisted-by: LLM
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxx>
Signed-off-by: Jared Wuerzburger <jwuerz@xxxxxxxxx>
---

Notes:
    Jonathan, the full DSDT excerpt is in the cover letter; a Link: to the
    series (or b4 shazam -M) would keep it reachable from the commit.

 drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c
index c4097ce2bf..11e5ec3798 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c
@@ -145,6 +145,7 @@ MODULE_DEVICE_TABLE(of, st_lsm6dsx_i2c_of_match);
 static const struct acpi_device_id st_lsm6dsx_i2c_acpi_match[] = {
 	{ .id = "SMO8B30", .driver_data = ST_LSM6DS3TRC_ID },
 	{ .id = "SMOCF00", .driver_data = ST_LSM6DSO_ID },
+	{ .id = "SMOCF05", .driver_data = ST_LSM6DS3TRC_ID },
 	{ }
 };
 MODULE_DEVICE_TABLE(acpi, st_lsm6dsx_i2c_acpi_match);
-- 
2.55.0