Commit dc3d25f2 authored by Jonathan Cameron's avatar Jonathan Cameron Committed by Jonathan Cameron
Browse files

iio: imu: lsm6dsx: Add ACPI mount matrix retrieval 



DSDT ROTM method seen in the wild with SMO8B30 _HID.
Making assumption it is similar to that used for bmc150 plus
information from Darrell that the rotation is out by 90 degrees at boot.

Method (ROTM, 0, NotSerialized)
{
    Name (RBUF, Package (0x03)
    {
        "0 -1 0",
        "1 0 0",
        "0 0 1"
    })
    Return (RBUF) /* \_SB_.PCI0.I2C5.DEV_.ROTM.RBUF */
}

Reported-by: default avatarDarrell Kavanagh <darrell.kavanagh@gmail.com>
Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
Tested-by: default avatarDarrell Kavanagh <darrell.kavanagh@gmail.org>
Link: https://lore.kernel.org/r/20230130201018.981024-3-jic23@kernel.org


Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent bd66b6ac

drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c

+74 −3
Original line number Diff line number Diff line
@@ -56,6 +56,7 @@ 


#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/acpi.h>

#include <linux/delay.h>

#include <linux/iio/events.h>

#include <linux/iio/iio.h>
@@ -2624,6 +2625,73 @@ static int st_lsm6dsx_init_regulators(struct device *dev) 
	return 0;

}



#ifdef CONFIG_ACPI



static int lsm6dsx_get_acpi_mount_matrix(struct device *dev,

					 struct iio_mount_matrix *orientation)

{

	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };

	struct acpi_device *adev = ACPI_COMPANION(dev);

	union acpi_object *obj, *elements;

	acpi_status status;

	int i, j, val[3];

	char *str;



	if (!has_acpi_companion(dev))

		return -EINVAL;



	if (!acpi_has_method(adev->handle, "ROTM"))

		return -EINVAL;



	status = acpi_evaluate_object(adev->handle, "ROTM", NULL, &buffer);

	if (ACPI_FAILURE(status)) {

		dev_warn(dev, "Failed to get ACPI mount matrix: %d\n", status);

		return -EINVAL;

	}



	obj = buffer.pointer;

	if (obj->type != ACPI_TYPE_PACKAGE || obj->package.count != 3)

		goto unknown_format;



	elements = obj->package.elements;

	for (i = 0; i < 3; i++) {

		if (elements[i].type != ACPI_TYPE_STRING)

			goto unknown_format;



		str = elements[i].string.pointer;

		if (sscanf(str, "%d %d %d", &val[0], &val[1], &val[2]) != 3)

			goto unknown_format;



		for (j = 0; j < 3; j++) {

			switch (val[j]) {

			case -1: str = "-1"; break;

			case 0:  str = "0";  break;

			case 1:  str = "1";  break;

			default: goto unknown_format;

			}

			orientation->rotation[i * 3 + j] = str;

		}

	}



	kfree(buffer.pointer);

	return 0;



unknown_format:

	dev_warn(dev, "Unknown ACPI mount matrix format, ignoring\n");

	kfree(buffer.pointer);

	return -EINVAL;

}



#else



static int lsm6dsx_get_acpi_mount_matrix(struct device *dev,

					  struct iio_mount_matrix *orientation)

{

	return false;

}



#endif



int st_lsm6dsx_probe(struct device *dev, int irq, int hw_id,

		     struct regmap *regmap)

{
@@ -2698,9 +2766,12 @@ int st_lsm6dsx_probe(struct device *dev, int irq, int hw_id, 
			return err;

	}



	err = lsm6dsx_get_acpi_mount_matrix(hw->dev, &hw->orientation);

	if (err) {

		err = iio_read_mount_matrix(hw->dev, &hw->orientation);

		if (err)

			return err;

	}



	for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {

		if (!hw->iio_devs[i])