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>
This commit is contained in:
Srinivas Pandruvada 2014-01-10 16:00:05 -08:00 committed by Rafael J. Wysocki
parent d1badf8d43
commit c713cd7f2d

View file

@ -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);
}