iio: accel: bmc150: Set label based on accel-location on 2-accel yoga-style 2-in-1s

Some 2-in-1 laptops / convertibles with 360° (yoga-style) hinges,
use 2 bmc150 accelerometers, defined by a single BOSC0200 ACPI
device node (1 in their base and 1 in their display).

Since in this case we know the location of each accelerometer,
set the label for the accelerometers to the standardized
"accel-display" resp. "accel-base" labels. This way userspace
can use the labels to get the location.

This was tested on a Lenovo ThinkPad Yoga 11e 4th gen (N3450 CPU).

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210207160901.110643-3-hdegoede@redhat.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/accel/bmc150-accel-core.c b/drivers/iio/accel/bmc150-accel-core.c
index 7e425eb..b0dbd12 100644 (file)
--- a/drivers/iio/accel/bmc150-accel-core.c
+++ b/drivers/iio/accel/bmc150-accel-core.c
@@ -443,26 +443,32 @@ static bool bmc150_apply_acpi_orientation(struct device *dev,
                                          struct iio_mount_matrix *orientation)
 {
        struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+       struct iio_dev *indio_dev = dev_get_drvdata(dev);
        struct acpi_device *adev = ACPI_COMPANION(dev);
+       char *name, *alt_name, *label, *str;
        union acpi_object *obj, *elements;
-       char *name, *alt_name, *str;
        acpi_status status;
        int i, j, val[3];
 
        if (!adev || !acpi_dev_hid_uid_match(adev, "BOSC0200", NULL))
                return false;
 
-       if (strcmp(dev_name(dev), "i2c-BOSC0200:base") == 0)
+       if (strcmp(dev_name(dev), "i2c-BOSC0200:base") == 0) {
                alt_name = "ROMK";
-       else
+               label = "accel-base";
+       } else {
                alt_name = "ROMS";
+               label = "accel-display";
+       }
 
-       if (acpi_has_method(adev->handle, "ROTM"))
+       if (acpi_has_method(adev->handle, "ROTM")) {
                name = "ROTM";
-       else if (acpi_has_method(adev->handle, alt_name))
+       } else if (acpi_has_method(adev->handle, alt_name)) {
                name = alt_name;
-       else
+               indio_dev->label = label;
+       } else {
                return false;
+       }
 
        status = acpi_evaluate_object(adev->handle, name, NULL, &buffer);
        if (ACPI_FAILURE(status)) {