[U-Boot] [PATCH 2/3] sunxi: video: Add support for external DAC enable pin

[Hans de Goede]

Hi,

On 12-01-15 11:02, Chen-Yu Tsai wrote:
> The external DAC for VGA output might have either a power or reset
> control pin that needs to be pulled up, as is the case on the
> Hummingbird A31.
>
> Signed-off-by: Chen-Yu Tsai <wens at csie.org>
> ---
>   board/sunxi/Kconfig           |  8 ++++++++
>   drivers/video/sunxi_display.c | 18 ++++++++++++++++++
>   2 files changed, 26 insertions(+)
>
> diff --git a/board/sunxi/Kconfig b/board/sunxi/Kconfig
> index bce270e..e9a6b3c 100644
> --- a/board/sunxi/Kconfig
> +++ b/board/sunxi/Kconfig
> @@ -315,6 +315,14 @@ config VIDEO_VGA_VIA_LCD
>   	LCD interface driving a VGA connector, such as found on the
>   	Olimex A13 boards.
>
> +config VIDEO_VGA_EXTERNAL_DAC_EN
> +	string "LCD panel power enable pin"
> +	depends on VIDEO_VGA_VIA_LCD
> +	default ""
> +	---help---
> +	Set the enable pin for the external VGA DAC. This takes a string in the
> +	format understood by sunxi_name_to_gpio, e.g. PH1 for pin 1 of port H.
> +
>   config VIDEO_LCD_MODE
>   	string "LCD panel timing details"
>   	depends on VIDEO
> diff --git a/drivers/video/sunxi_display.c b/drivers/video/sunxi_display.c
> index 47d820d..1052af2 100644
> --- a/drivers/video/sunxi_display.c
> +++ b/drivers/video/sunxi_display.c
> @@ -813,6 +813,23 @@ static void sunxi_drc_init(void)
>   #endif
>   }
>
> +#ifdef CONFIG_VIDEO_VGA_VIA_LCD
> +static void sunxi_vga_external_dac_enable(void)
> +{
> +	int pin;
> +
> +	/*
> +	 * Start with backlight disabled to avoid the screen flashing to
> +	 * white while the lcd inits.
> +	 */

This comment seems wrong, copy & paste error ?

Let me know if you agree that it is wrong, then I'll drop it before applying
the series, not need to resend.

Regards,

Hans


> +	pin = sunxi_name_to_gpio(CONFIG_VIDEO_VGA_EXTERNAL_DAC_EN);
> +	if (pin != -1) {
> +		gpio_request(pin, "vga_enable");
> +		gpio_direction_output(pin, 1);
> +	}
> +}
> +#endif /* CONFIG_VIDEO_VGA_VIA_LCD */
> +
>   static void sunxi_engines_init(void)
>   {
>   	sunxi_composer_init();
> @@ -860,6 +877,7 @@ static void sunxi_mode_set(const struct ctfb_res_modes *mode,
>   		sunxi_lcdc_tcon0_mode_set(mode);
>   		sunxi_composer_enable();
>   		sunxi_lcdc_enable();
> +		sunxi_vga_external_dac_enable();
>   #endif
>   		break;
>   	}
>