ACPI: Add user space interface for identification objects

ACPI devices are glued with physical devices through _ADR object, ACPI
enumerated devices are identified with _UID object.  Currently we can
observe _HID/_CID through sysfs interfaces (hid/modalias), but there's
no way for us to check _ADR/_UID from user space.  This patch closes
this gap for ACPI developers and users.

[rjw: Modified the subject and changelog slightly.]
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Lv Zheng 2012-10-30 14:43:26 +01:00 committed by Rafael J. Wysocki
parent ccf7804026
commit 923d4a45a9

View File

@ -220,6 +220,25 @@ acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *bu
}
static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
static ssize_t acpi_device_uid_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct acpi_device *acpi_dev = to_acpi_device(dev);
return sprintf(buf, "%s\n", acpi_dev->pnp.unique_id);
}
static DEVICE_ATTR(uid, 0444, acpi_device_uid_show, NULL);
static ssize_t acpi_device_adr_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct acpi_device *acpi_dev = to_acpi_device(dev);
return sprintf(buf, "0x%08x\n",
(unsigned int)(acpi_dev->pnp.bus_address));
}
static DEVICE_ATTR(adr, 0444, acpi_device_adr_show, NULL);
static ssize_t
acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
struct acpi_device *acpi_dev = to_acpi_device(dev);
@ -304,6 +323,11 @@ static int acpi_device_setup_files(struct acpi_device *dev)
goto end;
}
if (dev->flags.bus_address)
result = device_create_file(&dev->dev, &dev_attr_adr);
if (dev->pnp.unique_id)
result = device_create_file(&dev->dev, &dev_attr_uid);
/*
* If device has _EJ0, 'eject' file is created that is used to trigger
* hot-removal function from userland.
@ -335,6 +359,10 @@ static void acpi_device_remove_files(struct acpi_device *dev)
if (ACPI_SUCCESS(status))
device_remove_file(&dev->dev, &dev_attr_eject);
if (dev->pnp.unique_id)
device_remove_file(&dev->dev, &dev_attr_uid);
if (dev->flags.bus_address)
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 (dev->handle)