ASUS Zenbooks need several special ACPI calls to enable the ALS peripheral.
Otherwise, reads just return 0.
Signed-off-by: Josef Gajdusek <a...@atx.name>
---
drivers/iio/light/acpi-als.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/drivers/iio/light/acpi-als.c b/drivers/iio/light/acpi-als.c
index f0b47c5..1fe2cd8 100644
--- a/drivers/iio/light/acpi-als.c
+++ b/drivers/iio/light/acpi-als.c
@@ -39,6 +39,9 @@
#define ACPI_ALS_DEVICE_NAME "acpi-als"
#define ACPI_ALS_NOTIFY_ILLUMINANCE 0x80
+#define ACPI_ALS_ASUS_TALS "\\_SB.PCI0.LPCB.EC0.TALS"
+#define ACPI_ALS_ASUS_ALSC "\\_SB.ATKD.ALSC"
+
ACPI_MODULE_NAME("acpi-als");
/*
@@ -180,6 +183,8 @@ static int acpi_als_add(struct acpi_device *device)
struct acpi_als *als;
struct iio_dev *indio_dev;
struct iio_buffer *buffer;
+ acpi_handle handle_tals, handle_alsc;
+ acpi_status status_tals, status_alsc;
indio_dev = devm_iio_device_alloc(&device->dev, sizeof(*als));
if (!indio_dev)
@@ -191,6 +196,18 @@ static int acpi_als_add(struct acpi_device *device)
als->device = device;
mutex_init(&als->lock);
+ /* ASUS Zenbooks need this to enable ALS */
+ status_tals = acpi_get_handle(NULL, ACPI_ALS_ASUS_TALS, &handle_tals);
+ status_alsc = acpi_get_handle(NULL, ACPI_ALS_ASUS_ALSC, &handle_alsc);
+ /* So far only devices with both have been observed */
+ if (ACPI_SUCCESS(status_tals) ^ ACPI_SUCCESS(status_alsc))
+ dev_warn(&device->dev, "Attempting to enable ACPI ALS, but
found only one of \""
+ ACPI_ALS_ASUS_TALS "\" and \"" ACPI_ALS_ASUS_ALSC
"\"");
+ if (ACPI_SUCCESS(status_tals))
+ acpi_execute_simple_method(handle_tals, NULL, 1);
+ if (ACPI_SUCCESS(status_alsc))
+ acpi_execute_simple_method(handle_alsc, NULL, 1);
+
indio_dev->name = ACPI_ALS_DEVICE_NAME;
indio_dev->dev.parent = &device->dev;
indio_dev->info = &acpi_als_info;
--
2.10.2
