ACPI: support acpi_device_ops .notify methods

This patch adds support for ACPI device driver .notify() methods.  If
such a method is present, Linux/ACPI installs a handler for device
notifications (but not for system notifications such as Bus Check,
Device Check, etc).  When a device notification occurs, Linux/ACPI
passes it on to the driver's .notify() method.

In most cases, this removes the need for drivers to install their own
handlers for device-specific notifications.

For fixed hardware devices like some power and sleep buttons, there's
no notification value because there's no control method to execute a
Notify opcode.  When a fixed hardware device generates an event, we
handle it the same as a regular device notification, except we send
a ACPI_FIXED_HARDWARE_EVENT value.  This is outside the normal 0x0-0xff
range used by Notify opcodes.

Several drivers install their own handlers for system Bus Check and
Device Check notifications so they can support hot-plug.  This patch
doesn't affect that usage.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Reviewed-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
Bjorn Helgaas 2009-03-30 17:48:13 +00:00 committed by Len Brown
parent 478c6a43fc
commit 46ec8598fd
3 changed files with 83 additions and 0 deletions

View File

@ -359,6 +359,61 @@ static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
return 0;
}
static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
{
struct acpi_device *device = data;
device->driver->ops.notify(device, event);
}
static acpi_status acpi_device_notify_fixed(void *data)
{
struct acpi_device *device = data;
acpi_device_notify(device->handle, ACPI_FIXED_HARDWARE_EVENT, device);
return AE_OK;
}
static int acpi_device_install_notify_handler(struct acpi_device *device)
{
acpi_status status;
char *hid;
hid = acpi_device_hid(device);
if (!strcmp(hid, ACPI_BUTTON_HID_POWERF))
status =
acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
acpi_device_notify_fixed,
device);
else if (!strcmp(hid, ACPI_BUTTON_HID_SLEEPF))
status =
acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
acpi_device_notify_fixed,
device);
else
status = acpi_install_notify_handler(device->handle,
ACPI_DEVICE_NOTIFY,
acpi_device_notify,
device);
if (ACPI_FAILURE(status))
return -EINVAL;
return 0;
}
static void acpi_device_remove_notify_handler(struct acpi_device *device)
{
if (!strcmp(acpi_device_hid(device), ACPI_BUTTON_HID_POWERF))
acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
acpi_device_notify_fixed);
else if (!strcmp(acpi_device_hid(device), ACPI_BUTTON_HID_SLEEPF))
acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
acpi_device_notify_fixed);
else
acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
acpi_device_notify);
}
static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
static int acpi_start_single_object(struct acpi_device *);
static int acpi_device_probe(struct device * dev)
@ -371,6 +426,20 @@ static int acpi_device_probe(struct device * dev)
if (!ret) {
if (acpi_dev->bus_ops.acpi_op_start)
acpi_start_single_object(acpi_dev);
if (acpi_drv->ops.notify) {
ret = acpi_device_install_notify_handler(acpi_dev);
if (ret) {
if (acpi_drv->ops.stop)
acpi_drv->ops.stop(acpi_dev,
acpi_dev->removal_type);
if (acpi_drv->ops.remove)
acpi_drv->ops.remove(acpi_dev,
acpi_dev->removal_type);
return ret;
}
}
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Found driver [%s] for device [%s]\n",
acpi_drv->name, acpi_dev->pnp.bus_id));
@ -385,6 +454,8 @@ static int acpi_device_remove(struct device * dev)
struct acpi_driver *acpi_drv = acpi_dev->driver;
if (acpi_drv) {
if (acpi_drv->ops.notify)
acpi_device_remove_notify_handler(acpi_dev);
if (acpi_drv->ops.stop)
acpi_drv->ops.stop(acpi_dev, acpi_dev->removal_type);
if (acpi_drv->ops.remove)

View File

@ -95,6 +95,7 @@ typedef int (*acpi_op_suspend) (struct acpi_device * device,
typedef int (*acpi_op_resume) (struct acpi_device * device);
typedef int (*acpi_op_bind) (struct acpi_device * device);
typedef int (*acpi_op_unbind) (struct acpi_device * device);
typedef void (*acpi_op_notify) (struct acpi_device * device, u32 event);
struct acpi_bus_ops {
u32 acpi_op_add:1;
@ -110,6 +111,7 @@ struct acpi_device_ops {
acpi_op_resume resume;
acpi_op_bind bind;
acpi_op_unbind unbind;
acpi_op_notify notify;
};
struct acpi_driver {

View File

@ -67,6 +67,16 @@
#define ACPI_BAY_HID "LNXIOBAY"
#define ACPI_DOCK_HID "LNXDOCK"
/*
* For fixed hardware buttons, we fabricate acpi_devices with HID
* ACPI_BUTTON_HID_POWERF or ACPI_BUTTON_HID_SLEEPF. Fixed hardware
* signals only an event; it doesn't supply a notification value.
* To allow drivers to treat notifications from fixed hardware the
* same as those from real devices, we turn the events into this
* notification value.
*/
#define ACPI_FIXED_HARDWARE_EVENT 0x100
/* --------------------------------------------------------------------------
PCI
-------------------------------------------------------------------------- */