[PATCH] ACPI/SCAN: _STA status read
From: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Date: 2014-01-11 00:02:43
Also in:
linux-acpi, lkml
Subsystem:
acpi, the rest · Maintainers:
"Rafael J. Wysocki", Linus Torvalds
This patch adds a "status" attribute for an acpi device. This status attribute shows the value of _STA object. The _STA object returns current status of an ACPI device to show enabled, disabled or removed. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> --- drivers/acpi/scan.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+)
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index fd39459..a5f4a60 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c@@ -567,6 +567,20 @@ 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};
@@ -622,6 +636,12 @@ 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.
@@ -677,6 +697,8 @@ 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); }
--
1.8.3.1