Felix Held has submitted this change. ( https://review.coreboot.org/c/coreboot/+/80179?usp=email )
Change subject: i2c/drivers/generic: Add support for including a rotation matrix ......................................................................
i2c/drivers/generic: Add support for including a rotation matrix
The Rotation Matrix allows the specification of a 3x3 matrix representing the orientation of devices, such as accelerometers. Each value in the matrix can be one of -1, 0, or 1, indicating the transformation applied to the device's axes.
It is expected by Linux and required for the OS to interpret the data from the device correctly. It is used by various drivers, mainly in `iio/accel`.
It was tested on Ubuntu, by rotating the device and verifying the orientation was correct.
Signed-off-by: Sean Rhodes sean@starlabs.systems Change-Id: Id4a940d999a0e300a6fe21269f18bab6e3c0523c Reviewed-on: https://review.coreboot.org/c/coreboot/+/80179 Reviewed-by: Matt DeVillier matt.devillier@gmail.com Tested-by: build bot (Jenkins) no-reply@coreboot.org Reviewed-by: Felix Held felix-coreboot@felixheld.de --- M src/drivers/i2c/generic/chip.h M src/drivers/i2c/generic/generic.c 2 files changed, 32 insertions(+), 0 deletions(-)
Approvals: Matt DeVillier: Looks good to me, approved Felix Held: Looks good to me, but someone else must approve build bot (Jenkins): Verified
diff --git a/src/drivers/i2c/generic/chip.h b/src/drivers/i2c/generic/chip.h index 8e13ffc..227cb61 100644 --- a/src/drivers/i2c/generic/chip.h +++ b/src/drivers/i2c/generic/chip.h @@ -69,6 +69,19 @@ /* Delay to be inserted after enabling stop. */ unsigned int stop_off_delay_ms;
+ /* + * The Rotation Matrix' allows specifying a 3x3 matrix representing + * the orientation of devices, such as accelerometers. Each value in + * the matrix can be one of -1, 0, or 1, indicating the transformation + * applied to the device's axes. + * + * It is expected by linux and required for the OS to correctly interpret + * the data from the device. + */ + bool has_rotation_matrix; + int rotation_matrix[9]; + + /* Generic properties for exporting device-specific data to the OS */ struct acpi_dp property_list[MAX_GENERIC_PROPERTY_LIST]; int property_count; diff --git a/src/drivers/i2c/generic/generic.c b/src/drivers/i2c/generic/generic.c index 2a4acb2..03018ee 100644 --- a/src/drivers/i2c/generic/generic.c +++ b/src/drivers/i2c/generic/generic.c @@ -160,6 +160,25 @@ acpi_device_add_power_res(&power_res_params); }
+ /* Rotation Matrix */ + if (config->has_rotation_matrix) { + acpigen_write_method("ROTM", 0); + acpigen_write_package(3); + + for (int i = 0; i < 3; i++) { + char matrix_row[12]; + snprintf(matrix_row, sizeof(matrix_row), "%d %d %d", + config->rotation_matrix[i * 3 + 0], + config->rotation_matrix[i * 3 + 1], + config->rotation_matrix[i * 3 + 2]); + + acpigen_write_string(matrix_row); + } + + acpigen_pop_len(); + acpigen_pop_len(); + } + /* Callback if any. */ if (callback) callback(dev);