Re: [PATCH 6/10] ACPI: register ACPI Video LCD as generic thermal cooling device

[Matthew Garrett <mjg59@srcf.ucam.org>]

On Thu, Jan 17, 2008 at 03:51:22PM +0800, Zhang Rui wrote:
> From: Zhang Rui <rui.zhang@intel.com>
> 
> Register ACPI video device as thermal cooling devices as they may be listed
> in _TZD method and the backlight control can be used for throttling.

I'm worried to some extent about how ungeneric this is. A thermal zone 
may cover any devices, not just processor and video ones. Perhaps this 
should be added to the acpi_device struct instead, and then let 
individual drivers implement whatever callbacks are appropriate?

> +static int
> +video_set_cur_state(struct thermal_cooling_device *cdev, unsigned int state)
> +{
> +	struct acpi_device *device = cdev->devdata;
> +	struct acpi_video_device *video = acpi_driver_data(device);
> +	int level;
> +
> +	if ( state >= video->brightness->count - 2)
> +		return -EINVAL;
> +
> +	state = video->brightness->count - state;
> +	level = video->brightness->levels[state -1];
> +	return acpi_video_device_lcd_set_level(video, level);

This all seems like duplication of the backlight interface?

(Speaking of which - Len, what's happening with my patches to the video 
driver? Some feedback would be nice)

-- 
Matthew Garrett | mjg59@srcf.ucam.org