Merge tag 'staging-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging/IIO updates from Greg KH:
 "Here is the big staging/iio driver pull request for 5.1-rc1.

  Lots of good IIO driver updates and cleanups in here as always.
  Combined with the removal of the xgifb driver, we have a net "loss" of
  over 9000 lines in the pull request, always a nice thing.

  As the outreachy application process is currently happening, there are
  loads of tiny checkpatch cleanup fixes all over the staging tree,
  which accounts for the majority of the fixups"

* tag 'staging-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (341 commits)
  staging: mt7621-dma: remove license boilerplate text
  staging: mt7621-dma: add SPDX GPL-2.0+ license identifier
  Staging: ks7010: Replace typecast to int
  Staging: vt6655: Align a static function declaration
  staging: speakup: fix line over 80 characters.
  staging: mt7621-eth: Remove license boilerplate text
  staging: mt7621-eth: Add SPDX license identifier
  staging: ks7010: removed custom Michael MIC implementation.
  staging: rtl8192e: Fix space and suspect issue
  Staging: vt6655: Modify comment style of SPDX License Identifier
  Staging: vt6655: Modify comment style for SPDX-License-Identifier
  Staging: vt6655: Align a function declaration
  Staging: vt6655: Alignment of function declaration
  staging: rtl8712: Fix indentation issue
  staging: wilc1000: fix incorrent type in initializer
  staging: rtl8188eu: remove unused P2P_PRIVATE_IOCTL_SET_LEN
  staging: rtl8188eu: remove unused enum P2P_PROTO_WK_ID
  staging: rtl8723bs: Remove duplicated include from drv_types.h
  Staging: vt6655: Alignment should match open parenthesis
  staging: erofs: fix mis-acted TAIL merging behavior
  ...

1 files changed, 170 insertions, 1 deletions

diff --git a/drivers/iio/accel/st_accel_core.c b/drivers/iio/accel/st_accel_core.c
index f7b471121508..a3c0916479fa 100644
--- a/drivers/iio/accel/st_accel_core.c
+++ b/drivers/iio/accel/st_accel_core.c
@@ -11,6 +11,7 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/slab.h>
+#include <linux/acpi.h>
 #include <linux/errno.h>
 #include <linux/types.h>
 #include <linux/mutex.h>
@@ -918,12 +919,167 @@ static const struct iio_trigger_ops st_accel_trigger_ops = {
 #define ST_ACCEL_TRIGGER_OPS NULL
 #endif
 
+static const struct iio_mount_matrix *
+get_mount_matrix(const struct iio_dev *indio_dev,
+		 const struct iio_chan_spec *chan)
+{
+	struct st_sensor_data *adata = iio_priv(indio_dev);
+
+	return adata->mount_matrix;
+}
+
+static const struct iio_chan_spec_ext_info mount_matrix_ext_info[] = {
+	IIO_MOUNT_MATRIX(IIO_SHARED_BY_ALL, get_mount_matrix),
+	{ },
+};
+
+/* Read ST-specific _ONT orientation data from ACPI and generate an
+ * appropriate mount matrix.
+ */
+static int apply_acpi_orientation(struct iio_dev *indio_dev,
+				  struct iio_chan_spec *channels)
+{
+#ifdef CONFIG_ACPI
+	struct st_sensor_data *adata = iio_priv(indio_dev);
+	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
+	struct acpi_device *adev;
+	union acpi_object *ont;
+	union acpi_object *elements;
+	acpi_status status;
+	int ret = -EINVAL;
+	unsigned int val;
+	int i, j;
+	int final_ont[3][3] = { { 0 }, };
+
+	/* For some reason, ST's _ONT translation does not apply directly
+	 * to the data read from the sensor. Another translation must be
+	 * performed first, as described by the matrix below. Perhaps
+	 * ST required this specific translation for the first product
+	 * where the device was mounted?
+	 */
+	const int default_ont[3][3] = {
+		{  0,  1,  0 },
+		{ -1,  0,  0 },
+		{  0,  0, -1 },
+	};
+
+
+	adev = ACPI_COMPANION(adata->dev);
+	if (!adev)
+		return 0;
+
+	/* Read _ONT data, which should be a package of 6 integers. */
+	status = acpi_evaluate_object(adev->handle, "_ONT", NULL, &buffer);
+	if (status == AE_NOT_FOUND) {
+		return 0;
+	} else if (ACPI_FAILURE(status)) {
+		dev_warn(&indio_dev->dev, "failed to execute _ONT: %d\n",
+			 status);
+		return status;
+	}
+
+	ont = buffer.pointer;
+	if (ont->type != ACPI_TYPE_PACKAGE || ont->package.count != 6)
+		goto out;
+
+	/* The first 3 integers provide axis order information.
+	 * e.g. 0 1 2 would indicate normal X,Y,Z ordering.
+	 * e.g. 1 0 2 indicates that data arrives in order Y,X,Z.
+	 */
+	elements = ont->package.elements;
+	for (i = 0; i < 3; i++) {
+		if (elements[i].type != ACPI_TYPE_INTEGER)
+			goto out;
+
+		val = elements[i].integer.value;
+		if (val < 0 || val > 2)
+			goto out;
+
+		/* Avoiding full matrix multiplication, we simply reorder the
+		 * columns in the default_ont matrix according to the
+		 * ordering provided by _ONT.
+		 */
+		final_ont[0][i] = default_ont[0][val];
+		final_ont[1][i] = default_ont[1][val];
+		final_ont[2][i] = default_ont[2][val];
+	}
+
+	/* The final 3 integers provide sign flip information.
+	 * 0 means no change, 1 means flip.
+	 * e.g. 0 0 1 means that Z data should be sign-flipped.
+	 * This is applied after the axis reordering from above.
+	 */
+	elements += 3;
+	for (i = 0; i < 3; i++) {
+		if (elements[i].type != ACPI_TYPE_INTEGER)
+			goto out;
+
+		val = elements[i].integer.value;
+		if (val != 0 && val != 1)
+			goto out;
+		if (!val)
+			continue;
+
+		/* Flip the values in the indicated column */
+		final_ont[0][i] *= -1;
+		final_ont[1][i] *= -1;
+		final_ont[2][i] *= -1;
+	}
+
+	/* Convert our integer matrix to a string-based iio_mount_matrix */
+	adata->mount_matrix = devm_kmalloc(&indio_dev->dev,
+					   sizeof(*adata->mount_matrix),
+					   GFP_KERNEL);
+	if (!adata->mount_matrix) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	for (i = 0; i < 3; i++) {
+		for (j = 0; j < 3; j++) {
+			int matrix_val = final_ont[i][j];
+			char *str_value;
+
+			switch (matrix_val) {
+			case -1:
+				str_value = "-1";
+				break;
+			case 0:
+				str_value = "0";
+				break;
+			case 1:
+				str_value = "1";
+				break;
+			default:
+				goto out;
+			}
+			adata->mount_matrix->rotation[i * 3 + j] = str_value;
+		}
+	}
+
+	/* Expose the mount matrix via ext_info */
+	for (i = 0; i < indio_dev->num_channels; i++)
+		channels[i].ext_info = mount_matrix_ext_info;
+
+	ret = 0;
+	dev_info(&indio_dev->dev, "computed mount matrix from ACPI\n");
+
+out:
+	kfree(buffer.pointer);
+	return ret;
+#else /* !CONFIG_ACPI */
+	return 0;
+#endif
+}
+
 int st_accel_common_probe(struct iio_dev *indio_dev)
 {
 	struct st_sensor_data *adata = iio_priv(indio_dev);
 	struct st_sensors_platform_data *pdata =
 		(struct st_sensors_platform_data *)adata->dev->platform_data;
 	int irq = adata->get_irq_data_ready(indio_dev);
+	struct iio_chan_spec *channels;
+	size_t channels_size;
 	int err;
 
 	indio_dev->modes = INDIO_DIRECT_MODE;
@@ -942,9 +1098,22 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
 
 	adata->num_data_channels = ST_ACCEL_NUMBER_DATA_CHANNELS;
 	adata->multiread_bit = adata->sensor_settings->multi_read_bit;
-	indio_dev->channels = adata->sensor_settings->ch;
 	indio_dev->num_channels = ST_SENSORS_NUMBER_ALL_CHANNELS;
 
+	channels_size = indio_dev->num_channels * sizeof(struct iio_chan_spec);
+	channels = devm_kmemdup(&indio_dev->dev,
+				adata->sensor_settings->ch,
+				channels_size, GFP_KERNEL);
+	if (!channels) {
+		err = -ENOMEM;
+		goto st_accel_power_off;
+	}
+
+	if (apply_acpi_orientation(indio_dev, channels))
+		dev_warn(&indio_dev->dev,
+			 "failed to apply ACPI orientation data: %d\n", err);
+
+	indio_dev->channels = channels;
 	adata->current_fullscale = (struct st_sensor_fullscale_avl *)
 					&adata->sensor_settings->fs.fs_avl[0];
 	adata->odr = adata->sensor_settings->odr.odr_avl[0].hz;