video.c

linux 内核源代码

	active_device_list = kmalloc((1 +
				      dod->package.count) *
				     sizeof(struct
					    acpi_video_enumerated_device),
				     GFP_KERNEL);

	if (!active_device_list) {
		status = -ENOMEM;
		goto out;
	}

	count = 0;
	for (i = 0; i < dod->package.count; i++) {
		obj = &dod->package.elements[i];

		if (obj->type != ACPI_TYPE_INTEGER) {
			printk(KERN_ERR PREFIX "Invalid _DOD data\n");
			active_device_list[i].value.int_val =
			    ACPI_VIDEO_HEAD_INVALID;
		}
		active_device_list[i].value.int_val = obj->integer.value;
		active_device_list[i].bind_info = NULL;
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
				  (int)obj->integer.value));
		count++;
	}
	active_device_list[count].value.int_val = ACPI_VIDEO_HEAD_END;

	kfree(video->attached_array);

	video->attached_array = active_device_list;
	video->attached_count = count;
      out:
	kfree(buffer.pointer);
	return status;
}

/*
 *  Arg:
 *  	video	: video bus device 
 *  	event	: notify event
 *
 *  Return:
 *  	< 0	: error
 *  
 *	1. Find out the current active output device.
 *	2. Identify the next output device to switch to.
 *	3. call _DSS to do actual switch.
 */

static int acpi_video_switch_output(struct acpi_video_bus *video, int event)
{
	struct list_head *node;
	struct acpi_video_device *dev = NULL;
	struct acpi_video_device *dev_next = NULL;
	struct acpi_video_device *dev_prev = NULL;
	unsigned long state;
	int status = 0;

	mutex_lock(&video->device_list_lock);

	list_for_each(node, &video->video_device_list) {
		dev = container_of(node, struct acpi_video_device, entry);
		status = acpi_video_device_get_state(dev, &state);
		if (state & 0x2) {
			dev_next = container_of(node->next,
					struct acpi_video_device, entry);
			dev_prev = container_of(node->prev,
					struct acpi_video_device, entry);
			goto out;
		}
	}

	dev_next = container_of(node->next, struct acpi_video_device, entry);
	dev_prev = container_of(node->prev, struct acpi_video_device, entry);

 out:
	mutex_unlock(&video->device_list_lock);

	switch (event) {
	case ACPI_VIDEO_NOTIFY_CYCLE:
	case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT:
		acpi_video_device_set_state(dev, 0);
		acpi_video_device_set_state(dev_next, 0x80000001);
		break;
	case ACPI_VIDEO_NOTIFY_PREV_OUTPUT:
		acpi_video_device_set_state(dev, 0);
		acpi_video_device_set_state(dev_prev, 0x80000001);
	default:
		break;
	}

	return status;
}

static int
acpi_video_get_next_level(struct acpi_video_device *device,
			  u32 level_current, u32 event)
{
	int min, max, min_above, max_below, i, l, delta = 255;
	max = max_below = 0;
	min = min_above = 255;
	/* Find closest level to level_current */
	for (i = 0; i < device->brightness->count; i++) {
		l = device->brightness->levels[i];
		if (abs(l - level_current) < abs(delta)) {
			delta = l - level_current;
			if (!delta)
				break;
		}
	}
	/* Ajust level_current to closest available level */
	level_current += delta;
	for (i = 0; i < device->brightness->count; i++) {
		l = device->brightness->levels[i];
		if (l < min)
			min = l;
		if (l > max)
			max = l;
		if (l < min_above && l > level_current)
			min_above = l;
		if (l > max_below && l < level_current)
			max_below = l;
	}

	switch (event) {
	case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
		return (level_current < max) ? min_above : min;
	case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
		return (level_current < max) ? min_above : max;
	case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
		return (level_current > min) ? max_below : min;
	case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
	case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
		return 0;
	default:
		return level_current;
	}
}

static void
acpi_video_switch_brightness(struct acpi_video_device *device, int event)
{
	unsigned long level_current, level_next;
	acpi_video_device_lcd_get_level_current(device, &level_current);
	level_next = acpi_video_get_next_level(device, level_current, event);
	acpi_video_device_lcd_set_level(device, level_next);
}

static int
acpi_video_bus_get_devices(struct acpi_video_bus *video,
			   struct acpi_device *device)
{
	int status = 0;
	struct acpi_device *dev;

	acpi_video_device_enumerate(video);

	list_for_each_entry(dev, &device->children, node) {

		status = acpi_video_bus_get_one_device(dev, video);
		if (ACPI_FAILURE(status)) {
			ACPI_EXCEPTION((AE_INFO, status, "Cant attach device"));
			continue;
		}
	}
	return status;
}

static int acpi_video_bus_put_one_device(struct acpi_video_device *device)
{
	acpi_status status;
	struct acpi_video_bus *video;


	if (!device || !device->video)
		return -ENOENT;

	video = device->video;

	acpi_video_device_remove_fs(device->dev);

	status = acpi_remove_notify_handler(device->dev->handle,
					    ACPI_DEVICE_NOTIFY,
					    acpi_video_device_notify);
	backlight_device_unregister(device->backlight);
	video_output_unregister(device->output_dev);

	return 0;
}

static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
{
	int status;
	struct acpi_video_device *dev, *next;

	mutex_lock(&video->device_list_lock);

	list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {

		status = acpi_video_bus_put_one_device(dev);
		if (ACPI_FAILURE(status))
			printk(KERN_WARNING PREFIX
			       "hhuuhhuu bug in acpi video driver.\n");

		if (dev->brightness) {
			kfree(dev->brightness->levels);
			kfree(dev->brightness);
		}
		list_del(&dev->entry);
		kfree(dev);
	}

	mutex_unlock(&video->device_list_lock);

	return 0;
}

/* acpi_video interface */

static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
{
	return acpi_video_bus_DOS(video, 0, 0);
}

static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
{
	return acpi_video_bus_DOS(video, 0, 1);
}

static void acpi_video_bus_notify(acpi_handle handle, u32 event, void *data)
{
	struct acpi_video_bus *video = data;
	struct acpi_device *device = NULL;
	struct input_dev *input;
	int keycode;

	if (!video)
		return;

	device = video->device;
	input = video->input;

	switch (event) {
	case ACPI_VIDEO_NOTIFY_SWITCH:	/* User requested a switch,
					 * most likely via hotkey. */
		acpi_bus_generate_proc_event(device, event, 0);
		keycode = KEY_SWITCHVIDEOMODE;
		break;

	case ACPI_VIDEO_NOTIFY_PROBE:	/* User plugged in or removed a video
					 * connector. */
		acpi_video_device_enumerate(video);
		acpi_video_device_rebind(video);
		acpi_video_switch_output(video, event);
		acpi_bus_generate_proc_event(device, event, 0);
		keycode = KEY_SWITCHVIDEOMODE;
		break;

	case ACPI_VIDEO_NOTIFY_CYCLE:	/* Cycle Display output hotkey pressed. */
		acpi_video_switch_output(video, event);
		acpi_bus_generate_proc_event(device, event, 0);
		keycode = KEY_SWITCHVIDEOMODE;
		break;
	case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT:	/* Next Display output hotkey pressed. */
		acpi_video_switch_output(video, event);
		acpi_bus_generate_proc_event(device, event, 0);
		keycode = KEY_VIDEO_NEXT;
		break;
	case ACPI_VIDEO_NOTIFY_PREV_OUTPUT:	/* previous Display output hotkey pressed. */
		acpi_video_switch_output(video, event);
		acpi_bus_generate_proc_event(device, event, 0);
		keycode = KEY_VIDEO_PREV;
		break;

	default:
		keycode = KEY_UNKNOWN;
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Unsupported event [0x%x]\n", event));
		break;
	}

	input_report_key(input, keycode, 1);
	input_sync(input);
	input_report_key(input, keycode, 0);
	input_sync(input);

	return;
}

static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
{
	struct acpi_video_device *video_device = data;
	struct acpi_device *device = NULL;
	struct acpi_video_bus *bus;
	struct input_dev *input;
	int keycode;

	if (!video_device)
		return;

	device = video_device->dev;
	bus = video_device->video;
	input = bus->input;

	switch (event) {
	case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:	/* Cycle brightness */
		acpi_video_switch_brightness(video_device, event);
		acpi_bus_generate_proc_event(device, event, 0);
		keycode = KEY_BRIGHTNESS_CYCLE;
		break;
	case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:	/* Increase brightness */
		acpi_video_switch_brightness(video_device, event);
		acpi_bus_generate_proc_event(device, event, 0);
		keycode = KEY_BRIGHTNESSUP;
		break;
	case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:	/* Decrease brightness */
		acpi_video_switch_brightness(video_device, event);
		acpi_bus_generate_proc_event(device, event, 0);
		keycode = KEY_BRIGHTNESSDOWN;
		break;
	case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:	/* zero brightnesss */
		acpi_video_switch_brightness(video_device, event);
		acpi_bus_generate_proc_event(device, event, 0);
		keycode = KEY_BRIGHTNESS_ZERO;
		break;
	case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:	/* display device off */
		acpi_video_switch_brightness(video_device, event);
		acpi_bus_generate_proc_event(device, event, 0);
		keycode = KEY_DISPLAY_OFF;
		break;
	default:
		keycode = KEY_UNKNOWN;
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Unsupported event [0x%x]\n", event));
		break;
	}

	input_report_key(input, keycode, 1);
	input_sync(input);
	input_report_key(input, keycode, 0);
	input_sync(input);

	return;
}

static int instance;
static int acpi_video_bus_add(struct acpi_device *device)
{
	acpi_status status;
	struct acpi_video_bus *video;
	struct input_dev *input;
	int error;

	video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
	if (!video)
		return -ENOMEM;

	/* a hack to fix the duplicate name "VID" problem on T61 */
	if (!strcmp(device->pnp.bus_id, "VID")) {
		if (instance)
			device->pnp.bus_id[3] = '0' + instance;
		instance ++;
	}

	video->device = device;
	strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
	strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
	acpi_driver_data(device) = video;

	acpi_video_bus_find_cap(video);
	error = acpi_video_bus_check(video);
	if (error)
		goto err_free_video;

	error = acpi_video_bus_add_fs(device);
	if (error)
		goto err_free_video;

	mutex_init(&video->device_list_lock);
	INIT_LIST_HEAD(&video->video_device_list);

	acpi_video_bus_get_devices(video, device);
	acpi_video_bus_start_devices(video);

	status = acpi_install_notify_handler(device->handle,
					     ACPI_DEVICE_NOTIFY,
					     acpi_video_bus_notify, video);
	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
				  "Error installing notify handler\n"));
		error = -ENODEV;
		goto err_stop_video;
	}

	video->input = input = input_allocate_device();
	if (!input) {
		error = -ENOMEM;
		goto err_uninstall_notify;
	}

	snprintf(video->phys, sizeof(video->phys),
		"%s/video/input0", acpi_device_hid(video->device));

	input->name = acpi_device_name(video->device);
	input->phys = video->phys;
	input->id.bustype = BUS_HOST;
	input->id.product = 0x06;
	input->dev.parent = &device->dev;
	input->evbit[0] = BIT(EV_KEY);
	set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
	set_bit(KEY_VIDEO_NEXT, input->keybit);
	set_bit(KEY_VIDEO_PREV, input->keybit);
	set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
	set_bit(KEY_BRIGHTNESSUP, input->keybit);
	set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
	set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
	set_bit(KEY_DISPLAY_OFF, input->keybit);
	set_bit(KEY_UNKNOWN, input->keybit);

	error = input_register_device(input);
	if (error)
		goto err_free_input_dev;

	printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s  rom: %s  post: %s)\n",
	       ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
	       video->flags.multihead ? "yes" : "no",
	       video->flags.rom ? "yes" : "no",
	       video->flags.post ? "yes" : "no");

	return 0;

 err_free_input_dev:
	input_free_device(input);
 err_uninstall_notify:
	acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
				   acpi_video_bus_notify);
 err_stop_video:
	acpi_video_bus_stop_devices(video);
	acpi_video_bus_put_devices(video);
	kfree(video->attached_array);
	acpi_video_bus_remove_fs(device);
 err_free_video:
	kfree(video);
	acpi_driver_data(device) = NULL;

	return error;
}

static int acpi_video_bus_remove(struct acpi_device *device, int type)
{
	acpi_status status = 0;
	struct acpi_video_bus *video = NULL;


	if (!device || !acpi_driver_data(device))
		return -EINVAL;

	video = acpi_driver_data(device);

	acpi_video_bus_stop_devices(video);

	status = acpi_remove_notify_handler(video->device->handle,
					    ACPI_DEVICE_NOTIFY,
					    acpi_video_bus_notify);

	acpi_video_bus_put_devices(video);
	acpi_video_bus_remove_fs(device);

	input_unregister_device(video->input);
	kfree(video->attached_array);
	kfree(video);

	return 0;
}

static int __init acpi_video_init(void)
{
	int result = 0;


	/*
	   acpi_dbg_level = 0xFFFFFFFF;
	   acpi_dbg_layer = 0x08000000;
	 */

	acpi_video_dir = proc_mkdir(ACPI_VIDEO_CLASS, acpi_root_dir);
	if (!acpi_video_dir)
		return -ENODEV;
	acpi_video_dir->owner = THIS_MODULE;

	result = acpi_bus_register_driver(&acpi_video_bus);
	if (result < 0) {
		remove_proc_entry(ACPI_VIDEO_CLASS, acpi_root_dir);
		return -ENODEV;
	}

	return 0;
}

static void __exit acpi_video_exit(void)
{

	acpi_bus_unregister_driver(&acpi_video_bus);

	remove_proc_entry(ACPI_VIDEO_CLASS, acpi_root_dir);

	return;
}

module_init(acpi_video_init);
module_exit(acpi_video_exit);