scan.c

来自「Linux Kernel 2.6.9 for OMAP1710」· C语言 代码 · 共 1,076 行 · 第 1/2 页

/*
 * scan.c - support for transforming the ACPI namespace into individual objects
 */

#include <linux/init.h>
#include <linux/acpi.h>

#include <acpi/acpi_drivers.h>
#include <acpi/acinterp.h>	/* for acpi_ex_eisa_id_to_string() */


#define _COMPONENT		ACPI_BUS_COMPONENT
ACPI_MODULE_NAME		("scan")

#define STRUCT_TO_INT(s)	(*((int*)&s))

extern struct acpi_device		*acpi_root;


#define ACPI_BUS_CLASS			"system_bus"
#define ACPI_BUS_HID			"ACPI_BUS"
#define ACPI_BUS_DRIVER_NAME		"ACPI Bus Driver"
#define ACPI_BUS_DEVICE_NAME		"System Bus"

static LIST_HEAD(acpi_device_list);
spinlock_t acpi_device_lock = SPIN_LOCK_UNLOCKED;
LIST_HEAD(acpi_wakeup_device_list);

static void acpi_device_release(struct kobject * kobj)
{
	struct acpi_device * dev = container_of(kobj,struct acpi_device,kobj);
	if (dev->pnp.cid_list)
		kfree(dev->pnp.cid_list);
	kfree(dev);
}

static struct kobj_type ktype_acpi_ns = {
	.release	= acpi_device_release,
};

static struct kset acpi_namespace_kset = {
	.kobj		= { 
		.name = "namespace",
	},
	.subsys = &acpi_subsys,
	.ktype	= &ktype_acpi_ns,
};


static void acpi_device_register(struct acpi_device * device, struct acpi_device * parent)
{
	/*
	 * Linkage
	 * -------
	 * Link this device to its parent and siblings.
	 */
	INIT_LIST_HEAD(&device->children);
	INIT_LIST_HEAD(&device->node);
	INIT_LIST_HEAD(&device->g_list);

	spin_lock(&acpi_device_lock);
	if (device->parent) {
		list_add_tail(&device->node, &device->parent->children);
		list_add_tail(&device->g_list,&device->parent->g_list);
	} else
		list_add_tail(&device->g_list,&acpi_device_list);
	spin_unlock(&acpi_device_lock);

	kobject_init(&device->kobj);
	strlcpy(device->kobj.name,device->pnp.bus_id,KOBJ_NAME_LEN);
	if (parent)
		device->kobj.parent = &parent->kobj;
	device->kobj.ktype = &ktype_acpi_ns;
	device->kobj.kset = &acpi_namespace_kset;
	kobject_add(&device->kobj);
}

static int
acpi_device_unregister (
	struct acpi_device	*device, 
	int			type)
{
	kobject_unregister(&device->kobj);
	return 0;
}

void
acpi_bus_data_handler (
	acpi_handle		handle,
	u32			function,
	void			*context)
{
	ACPI_FUNCTION_TRACE("acpi_bus_data_handler");

	/* TBD */

	return_VOID;
}

static int
acpi_bus_get_power_flags (
	struct acpi_device	*device)
{
	acpi_status             status = 0;
	acpi_handle		handle = NULL;
	u32                     i = 0;

	ACPI_FUNCTION_TRACE("acpi_bus_get_power_flags");

	/*
	 * Power Management Flags
	 */
	status = acpi_get_handle(device->handle, "_PSC", &handle);
	if (ACPI_SUCCESS(status))
		device->power.flags.explicit_get = 1;
	status = acpi_get_handle(device->handle, "_IRC", &handle);
	if (ACPI_SUCCESS(status))
		device->power.flags.inrush_current = 1;

	/*
	 * Enumerate supported power management states
	 */
	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
		struct acpi_device_power_state *ps = &device->power.states[i];
		char		object_name[5] = {'_','P','R','0'+i,'\0'};

		/* Evaluate "_PRx" to se if power resources are referenced */
		acpi_evaluate_reference(device->handle, object_name, NULL,
			&ps->resources);
		if (ps->resources.count) {
			device->power.flags.power_resources = 1;
			ps->flags.valid = 1;
		}

		/* Evaluate "_PSx" to see if we can do explicit sets */
		object_name[2] = 'S';
		status = acpi_get_handle(device->handle, object_name, &handle);
		if (ACPI_SUCCESS(status)) {
			ps->flags.explicit_set = 1;
			ps->flags.valid = 1;
		}

		/* State is valid if we have some power control */
		if (ps->resources.count || ps->flags.explicit_set)
			ps->flags.valid = 1;

		ps->power = -1;		/* Unknown - driver assigned */
		ps->latency = -1;	/* Unknown - driver assigned */
	}

	/* Set defaults for D0 and D3 states (always valid) */
	device->power.states[ACPI_STATE_D0].flags.valid = 1;
	device->power.states[ACPI_STATE_D0].power = 100;
	device->power.states[ACPI_STATE_D3].flags.valid = 1;
	device->power.states[ACPI_STATE_D3].power = 0;

	/* TBD: System wake support and resource requirements. */

	device->power.state = ACPI_STATE_UNKNOWN;

	return 0;
}

static int
acpi_match_ids (
	struct acpi_device	*device,
	char			*ids)
{
	int error = 0;
	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};

	if (device->flags.hardware_id)
		if (strstr(ids, device->pnp.hardware_id))
			goto Done;

	if (device->flags.compatible_ids) {
		struct acpi_compatible_id_list *cid_list = device->pnp.cid_list;
		int i;

		/* compare multiple _CID entries against driver ids */
		for (i = 0; i < cid_list->count; i++)
		{
			if (strstr(ids, cid_list->id[i].value))
				goto Done;
		}
	}
	error = -ENOENT;

 Done:
	if (buffer.pointer)
		acpi_os_free(buffer.pointer);
	return error;
}

static acpi_status
acpi_bus_extract_wakeup_device_power_package (
	struct acpi_device	*device,
	union acpi_object	*package)
{
	int 	 i = 0;
	union acpi_object	*element = NULL;

	if (!device || !package || (package->package.count < 2))
		return AE_BAD_PARAMETER;

	element = &(package->package.elements[0]);
	if (!element)
		return AE_BAD_PARAMETER;
	if (element->type == ACPI_TYPE_PACKAGE) {
		if ((element->package.count < 2) ||
			(element->package.elements[0].type != ACPI_TYPE_LOCAL_REFERENCE) ||
			(element->package.elements[1].type != ACPI_TYPE_INTEGER))
			return AE_BAD_DATA;
		device->wakeup.gpe_device = element->package.elements[0].reference.handle;
		device->wakeup.gpe_number = (u32)element->package.elements[1].integer.value;
	}else if (element->type == ACPI_TYPE_INTEGER) {
		device->wakeup.gpe_number = element->integer.value;
	}else
		return AE_BAD_DATA;

	element = &(package->package.elements[1]);
	if (element->type != ACPI_TYPE_INTEGER) {
		return AE_BAD_DATA;
	}
	device->wakeup.sleep_state = element->integer.value;

	if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
		return AE_NO_MEMORY;
	}
	device->wakeup.resources.count = package->package.count - 2;
	for (i=0; i < device->wakeup.resources.count; i++) {
		element = &(package->package.elements[i + 2]);
		if (element->type != ACPI_TYPE_ANY ) {
			return AE_BAD_DATA;
		}

		device->wakeup.resources.handles[i] = element->reference.handle;
	}

	return AE_OK;
}

static int
acpi_bus_get_wakeup_device_flags (
	struct acpi_device	*device)
{
	acpi_status	status = 0;
	struct acpi_buffer	buffer = {ACPI_ALLOCATE_BUFFER, NULL};
	union acpi_object	*package = NULL;

	ACPI_FUNCTION_TRACE("acpi_bus_get_wakeup_flags");

	/* _PRW */
	status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PRW\n"));
		goto end;
	}

	package = (union acpi_object *) buffer.pointer;
	status = acpi_bus_extract_wakeup_device_power_package(device, package);
	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error extracting _PRW package\n"));
		goto end;
	}

	acpi_os_free(buffer.pointer);

	device->wakeup.flags.valid = 1;
	/* Power button, Lid switch always enable wakeup*/
	if (!acpi_match_ids(device, "PNP0C0D,PNP0C0C,PNP0C0E"))
		device->wakeup.flags.run_wake = 1;

	/* TBD: lock */
	INIT_LIST_HEAD(&device->wakeup_list);
	spin_lock(&acpi_device_lock);
	list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
	spin_unlock(&acpi_device_lock);

end:
	if (ACPI_FAILURE(status))
		device->flags.wake_capable = 0;
	return 0;
}

/* --------------------------------------------------------------------------
                              Performance Management
   -------------------------------------------------------------------------- */

static int
acpi_bus_get_perf_flags (
	struct acpi_device	*device)
{
	device->performance.state = ACPI_STATE_UNKNOWN;
	return 0;
}

/* --------------------------------------------------------------------------
                                 Driver Management
   -------------------------------------------------------------------------- */

static LIST_HEAD(acpi_bus_drivers);
static DECLARE_MUTEX(acpi_bus_drivers_lock);


/**
 * acpi_bus_match 
 * --------------
 * Checks the device's hardware (_HID) or compatible (_CID) ids to see if it
 * matches the specified driver's criteria.
 */
static int
acpi_bus_match (
	struct acpi_device	*device,
	struct acpi_driver	*driver)
{
	return acpi_match_ids(device, driver->ids);
}


/**
 * acpi_bus_driver_init 
 * --------------------
 * Used to initialize a device via its device driver.  Called whenever a 
 * driver is bound to a device.  Invokes the driver's add() and start() ops.
 */
static int
acpi_bus_driver_init (
	struct acpi_device	*device, 
	struct acpi_driver	*driver)
{
	int			result = 0;

	ACPI_FUNCTION_TRACE("acpi_bus_driver_init");

	if (!device || !driver)
		return_VALUE(-EINVAL);

	if (!driver->ops.add)
		return_VALUE(-ENOSYS);

	result = driver->ops.add(device);
	if (result) {
		device->driver = NULL;
		acpi_driver_data(device) = NULL;
		return_VALUE(result);
	}

	device->driver = driver;

	/*
	 * TBD - Configuration Management: Assign resources to device based
	 * upon possible configuration and currently allocated resources.
	 */

	if (driver->ops.start) {
		result = driver->ops.start(device);
		if (result && driver->ops.remove)
			driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
		return_VALUE(result);
	}

	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Driver successfully bound to device\n"));

	if (driver->ops.scan) {
		driver->ops.scan(device);
	}

	return_VALUE(0);
}

static int acpi_driver_attach(struct acpi_driver * drv)
{
	struct list_head * node, * next;
	int count = 0;

	ACPI_FUNCTION_TRACE("acpi_driver_attach");

	spin_lock(&acpi_device_lock);
	list_for_each_safe(node, next, &acpi_device_list) {
		struct acpi_device * dev = container_of(node, struct acpi_device, g_list);

		if (dev->driver || !dev->status.present)
			continue;
		spin_unlock(&acpi_device_lock);

		if (!acpi_bus_match(dev, drv)) {
			if (!acpi_bus_driver_init(dev, drv)) {
				atomic_inc(&drv->references);
				count++;
				ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
						  drv->name, dev->pnp.bus_id));
			}
		}
		spin_lock(&acpi_device_lock);
	}
	spin_unlock(&acpi_device_lock);
	return_VALUE(count);
}

static int acpi_driver_detach(struct acpi_driver * drv)
{
	struct list_head * node, * next;

	ACPI_FUNCTION_TRACE("acpi_driver_detach");

	spin_lock(&acpi_device_lock);
	list_for_each_safe(node,next,&acpi_device_list) {
		struct acpi_device * dev = container_of(node,struct acpi_device,g_list);

		if (dev->driver == drv) {
			spin_unlock(&acpi_device_lock);
			if (drv->ops.remove)
				drv->ops.remove(dev,ACPI_BUS_REMOVAL_NORMAL);
			spin_lock(&acpi_device_lock);
			dev->driver = NULL;
			dev->driver_data = NULL;
			atomic_dec(&drv->references);
		}
	}
	spin_unlock(&acpi_device_lock);
	return_VALUE(0);
}

/**
 * acpi_bus_register_driver 
 * ------------------------ 
 * Registers a driver with the ACPI bus.  Searches the namespace for all
 * devices that match the driver's criteria and binds.  Returns the
 * number of devices that were claimed by the driver, or a negative
 * error status for failure.
 */
int
acpi_bus_register_driver (
	struct acpi_driver	*driver)
{
	int count;

	ACPI_FUNCTION_TRACE("acpi_bus_register_driver");

	if (acpi_disabled)
		return_VALUE(-ENODEV);

	if (!driver)
		return_VALUE(-EINVAL);

	spin_lock(&acpi_device_lock);
	list_add_tail(&driver->node, &acpi_bus_drivers);
	spin_unlock(&acpi_device_lock);
	count = acpi_driver_attach(driver);

	return_VALUE(count);
}


/**
 * acpi_bus_unregister_driver 
 * --------------------------
 * Unregisters a driver with the ACPI bus.  Searches the namespace for all
 * devices that match the driver's criteria and unbinds.
 */
int
acpi_bus_unregister_driver (
	struct acpi_driver	*driver)
{
	int error = 0;

	ACPI_FUNCTION_TRACE("acpi_bus_unregister_driver");

	if (driver) {
		acpi_driver_detach(driver);

		if (!atomic_read(&driver->references)) {
			spin_lock(&acpi_device_lock);
			list_del_init(&driver->node);
			spin_unlock(&acpi_device_lock);
		} 
	} else 
		error = -EINVAL;
	return_VALUE(error);
}

/**
 * acpi_bus_find_driver 
 * --------------------
 * Parses the list of registered drivers looking for a driver applicable for
 * the specified device.
 */
static int
acpi_bus_find_driver (
	struct acpi_device	*device)
{
	int			result = 0;
	struct list_head	* node, *next;

	ACPI_FUNCTION_TRACE("acpi_bus_find_driver");

	if (!device->flags.hardware_id && !device->flags.compatible_ids)
		goto Done;

	spin_lock(&acpi_device_lock);
	list_for_each_safe(node,next,&acpi_bus_drivers) {
		struct acpi_driver * driver = container_of(node,struct acpi_driver,node);

		atomic_inc(&driver->references);
		spin_unlock(&acpi_device_lock);
		if (!acpi_bus_match(device, driver)) {
			result = acpi_bus_driver_init(device, driver);
			if (!result)
				goto Done;
		}
		atomic_dec(&driver->references);
		spin_lock(&acpi_device_lock);
	}
	spin_unlock(&acpi_device_lock);

 Done:
	return_VALUE(result);
}


/* --------------------------------------------------------------------------
                                 Device Enumeration
   -------------------------------------------------------------------------- */

static int 
acpi_bus_get_flags (
	struct acpi_device	*device)
{
	acpi_status		status = AE_OK;
	acpi_handle		temp = NULL;

	ACPI_FUNCTION_TRACE("acpi_bus_get_flags");

	/* Presence of _STA indicates 'dynamic_status' */
	status = acpi_get_handle(device->handle, "_STA", &temp);
	if (ACPI_SUCCESS(status))
		device->flags.dynamic_status = 1;