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authorSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>2014-01-10 16:00:05 -0800
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2014-01-11 01:53:13 +0100
commitc713cd7f2d799c50a0721bf51d178ea9567215dd (patch)
treed41b010703bca8b680054570511a4e88180d2fad /drivers/acpi/scan.c
parentd1badf8d4323cfc9325b06651bdfcf7df09f1f0e (diff)
ACPI / scan: ACPI device object sysfs attribute for _STA evaluation
This patch adds a "status" attribute for an ACPI device. This status attribute shows the value of the _STA object. The _STA object returns current status of an ACPI device: enabled, disabled, functioning, present. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> [rjw: Subject and changelog] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/scan.c')
-rw-r--r--drivers/acpi/scan.c22
1 files changed, 22 insertions, 0 deletions
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 32b340171d4..c0f57ff1502 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -602,6 +602,20 @@ acpi_device_sun_show(struct device *dev, struct device_attribute *attr,
}
static DEVICE_ATTR(sun, 0444, acpi_device_sun_show, NULL);
+static ssize_t status_show(struct device *dev, struct device_attribute *attr,
+ char *buf) {
+ struct acpi_device *acpi_dev = to_acpi_device(dev);
+ acpi_status status;
+ unsigned long long sta;
+
+ status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta);
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ return sprintf(buf, "%llu\n", sta);
+}
+static DEVICE_ATTR_RO(status);
+
static int acpi_device_setup_files(struct acpi_device *dev)
{
struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
@@ -657,6 +671,12 @@ static int acpi_device_setup_files(struct acpi_device *dev)
dev->pnp.sun = (unsigned long)-1;
}
+ if (acpi_has_method(dev->handle, "_STA")) {
+ result = device_create_file(&dev->dev, &dev_attr_status);
+ if (result)
+ goto end;
+ }
+
/*
* If device has _EJ0, 'eject' file is created that is used to trigger
* hot-removal function from userland.
@@ -712,6 +732,8 @@ static void acpi_device_remove_files(struct acpi_device *dev)
device_remove_file(&dev->dev, &dev_attr_adr);
device_remove_file(&dev->dev, &dev_attr_modalias);
device_remove_file(&dev->dev, &dev_attr_hid);
+ if (acpi_has_method(dev->handle, "_STA"))
+ device_remove_file(&dev->dev, &dev_attr_status);
if (dev->handle)
device_remove_file(&dev->dev, &dev_attr_path);
}