Re: [PATCH v3] toshiba_acpi: Add support for transflective LCD

[Seth Forshee <seth.forshee@canonical.com>]

On Thu, Apr 05, 2012 at 12:00:46AM +0900, Akio Idehara wrote:
> @@ -485,10 +506,23 @@ static int get_lcd(struct backlight_device *bd)
>  	struct toshiba_acpi_dev *dev = bl_get_data(bd);
>  	u32 hci_result;
>  	u32 value;
> +	bool enabled;
> +	int extra = 0;
> +
> +	if (dev->tr_backlight_supported) {
> +		if (!get_tr_backlight_status(dev, &enabled)) {
> +			if (!enabled)
> +				extra = 1;
> +			else
> +				return 0;
> +		} else {
> +			return -EIO;
> +		}
> +	}
>  
>  	hci_read1(dev, HCI_LCD_BRIGHTNESS, &value, &hci_result);
>  	if (hci_result == HCI_SUCCESS)
> -		return (value >> HCI_LCD_BRIGHTNESS_SHIFT);
> +		return (value >> HCI_LCD_BRIGHTNESS_SHIFT) + extra;

I'm still not crazy about the name. And really I think if
get_tr_backlight_status() is going to return an error code, when it
fails the return value should be propogated (even if it's the same in
this case). How about this?

	bool enabled;
	int ret;
       	int brightness = 0;

       	if (dev->tr_backlight_supported) {
       		ret = get_tr_backlight_status(dev, &enabled);
	       	if (ret)
       			return ret;
		if (enabled)
			return 0;
		brightness++;
	}

	hci_read1(dev, HCI_LCD_BRIGHTNESS, &value, &hci_result);
	if (hci_result == HCI_SUCCESS)
		return brightness + (value >> HCI_LCD_BRIGHTNESS_SHIFT);

>  static const struct backlight_ops toshiba_backlight_data = {
> +	.options	= BL_CORE_SUSPENDRESUME,

What's the reason for adding this? I don't see that it's useful unless
we're handling BL_CORE_SUSPENDED, which toshiba_acpi is not doing.

Cheers,
Seth