[PATCH] drivers/iio/accel/kxcjk-1013: Retrieve mount-matrix from ACPI

[Sean Rhodes]

Implement kxj_acpi_orientation to retrieve mount matrix
from ACPI ROTM method

Cc: Jonathan Cameron <jic23@xxxxxxxxxx>
Cc: Lars-Peter Clausen <lars@xxxxxxxxxx>
Cc: "Uwe Kleine-König" <u.kleine-koenig@xxxxxxxxxxxxxx>
Signed-off-by: Sean Rhodes <sean@starlabs.systems>
---
 drivers/iio/accel/kxcjk-1013.c | 87 ++++++++++++++++++++++++++++++++--
 1 file changed, 84 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/accel/kxcjk-1013.c b/drivers/iio/accel/kxcjk-1013.c
index 894709286b0c..33d7394f32eb 100644
--- a/drivers/iio/accel/kxcjk-1013.c
+++ b/drivers/iio/accel/kxcjk-1013.c
@@ -619,6 +619,84 @@ static int kxcjk1013_set_power_state(struct kxcjk1013_data *data, bool on)
 	return 0;
 }
 
+#ifdef CONFIG_ACPI
+/*
+ * Support for getting accelerometer information from KIOX000A ACPI nodes.
+ *
+ */
+static bool kxj_acpi_orientation(struct device *dev,
+				 struct iio_mount_matrix *orientation)
+{
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+	char *name, *str;
+	union acpi_object *obj, *elements;
+	acpi_status status;
+	int i, j, val[3];
+
+	if (acpi_has_method(adev->handle, "ROTM")) {
+		name = "ROTM";
+	} else {
+		return false;
+	}
+
+	status = acpi_evaluate_object(adev->handle, name, NULL, &buffer);
+	if (ACPI_FAILURE(status)) {
+		dev_warn(dev, "Failed to get ACPI mount matrix: %d\n", status);
+		return false;
+	}
+
+	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 true;
+
+unknown_format:
+	dev_warn(dev, "Unknown ACPI mount matrix format, ignoring\n");
+	kfree(buffer.pointer);
+	return false;
+}
+
+static bool kxj1009_apply_acpi_orientation(struct device *dev,
+					  struct iio_mount_matrix *orientation)
+{
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+
+	if (adev && acpi_dev_hid_uid_match(adev, "KIOX000A", NULL))
+		return kxj_acpi_orientation(dev, orientation);
+
+	return false;
+}
+#else
+static bool kxj1009_apply_acpi_orientation(struct device *dev,
+					  struct iio_mount_matrix *orientation)
+{
+	return false;
+}
+#endif
+
 static int kxcjk1013_chip_update_thresholds(struct kxcjk1013_data *data)
 {
 	int ret;
@@ -1449,9 +1527,12 @@ static int kxcjk1013_probe(struct i2c_client *client)
 	} else {
 		data->active_high_intr = true; /* default polarity */
 
-		ret = iio_read_mount_matrix(&client->dev, &data->orientation);
-		if (ret)
-			return ret;
+		if (!kxj1009_apply_acpi_orientation(&client->dev, &data->orientation)) {
+			ret = iio_read_mount_matrix(&client->dev, &data->orientation);
+			if (ret)
+				return ret;
+		}
+
 	}
 
 	ret = devm_regulator_bulk_get_enable(&client->dev,
-- 
2.40.1