iio: Allow to read mount matrix from ACPI

Currently mount matrix is allowed in Device Tree, though there is
no technical issue to extend it to support ACPI.

Convert the function to use device_property_read_string_array() and
thus allow to read mount matrix from ACPI if available.

Example of use in _DSD method:

  Name (_DSD, Package ()
  {
     ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
     Package ()
     {
        Package () { "mount-matrix", Package() {
                "1", "0",     "0",
                "0", "0.866", "0.5",
                "0", "-0.5",  "0.866",
        } },
     }
  })

At the same time drop the "of" prefix from its name and
convert current users.

No functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

1 files changed, 18 insertions, 28 deletions

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 4700fd5d8c90..f2ebca65f964 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -19,6 +19,7 @@
 #include <linux/device.h>
 #include <linux/fs.h>
 #include <linux/poll.h>
+#include <linux/property.h>
 #include <linux/sched.h>
 #include <linux/wait.h>
 #include <linux/cdev.h>
@@ -530,8 +531,8 @@ ssize_t iio_show_mount_matrix(struct iio_dev *indio_dev, uintptr_t priv,
 EXPORT_SYMBOL_GPL(iio_show_mount_matrix);
 
 /**
- * of_iio_read_mount_matrix() - retrieve iio device mounting matrix from
- *                              device-tree "mount-matrix" property
+ * iio_read_mount_matrix() - retrieve iio device mounting matrix from
+ *                           device "mount-matrix" property
  * @dev:	device the mounting matrix property is assigned to
  * @propname:	device specific mounting matrix property name
  * @matrix:	where to store retrieved matrix
@@ -541,40 +542,29 @@ EXPORT_SYMBOL_GPL(iio_show_mount_matrix);
  *
  * Return: 0 if success, or a negative error code on failure.
  */
-#ifdef CONFIG_OF
-int of_iio_read_mount_matrix(const struct device *dev,
-			     const char *propname,
-			     struct iio_mount_matrix *matrix)
+int iio_read_mount_matrix(struct device *dev, const char *propname,
+			  struct iio_mount_matrix *matrix)
 {
-	if (dev->of_node) {
-		int err = of_property_read_string_array(dev->of_node,
-				propname, matrix->rotation,
-				ARRAY_SIZE(iio_mount_idmatrix.rotation));
+	size_t len = ARRAY_SIZE(iio_mount_idmatrix.rotation);
+	int err;
 
-		if (err == ARRAY_SIZE(iio_mount_idmatrix.rotation))
-			return 0;
+	err = device_property_read_string_array(dev, propname,
+						matrix->rotation, len);
+	if (err == len)
+		return 0;
 
-		if (err >= 0)
-			/* Invalid number of matrix entries. */
-			return -EINVAL;
+	if (err >= 0)
+		/* Invalid number of matrix entries. */
+		return -EINVAL;
 
-		if (err != -EINVAL)
-			/* Invalid matrix declaration format. */
-			return err;
-	}
+	if (err != -EINVAL)
+		/* Invalid matrix declaration format. */
+		return err;
 
 	/* Matrix was not declared at all: fallback to identity. */
 	return iio_setup_mount_idmatrix(dev, matrix);
 }
-#else
-int of_iio_read_mount_matrix(const struct device *dev,
-			     const char *propname,
-			     struct iio_mount_matrix *matrix)
-{
-	return iio_setup_mount_idmatrix(dev, matrix);
-}
-#endif
-EXPORT_SYMBOL(of_iio_read_mount_matrix);
+EXPORT_SYMBOL(iio_read_mount_matrix);
 
 static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type,
 				  int size, const int *vals)