[PATCH v4 3/3] omap3: beaglexm: fix power on of DVI

[Aaro Koskinen]

Hi,

On Fri, 7 Jan 2011, Nishanth Menon wrote:
> From: Koen Kooi <koen at beagleboard.org>
>
> TFP410 DVI chip is used to provide display out.
> This chip is controlled by 2 lines:
> LDO which supplies the power is controlled over gpio + 2
> and the enable of the chip itself is done over gpio + 1
> NOTE: the LDO is necessary for LED, serial blocks as well.
>
> gpio + 1 was used to sense USB overcurrent in vanilla beagle.
>
> Without this fix, the display would not function as the LDO
> remains shut down.
>
> [nm at ti.com: split up, added descriptive changelogs]
> Signed-off-by: Nishanth Menon <nm at ti.com>
> Signed-off-by: Koen Kooi <koen at beagleboard.org>
> ---
> arch/arm/mach-omap2/board-omap3beagle.c |   20 +++++++++++++++++---
> 1 files changed, 17 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm/mach-omap2/board-omap3beagle.c b/arch/arm/mach-omap2/board-omap3beagle.c
> index d628f5e..7c82730 100644
> --- a/arch/arm/mach-omap2/board-omap3beagle.c
> +++ b/arch/arm/mach-omap2/board-omap3beagle.c
> @@ -293,9 +293,10 @@ static int beagle_twl_gpio_setup(struct device *dev,
> 	/* REVISIT: need ehci-omap hooks for external VBUS
> 	 * power switch and overcurrent detect
> 	 */
> -
> -	gpio_request(gpio + 1, "EHCI_nOC");
> -	gpio_direction_input(gpio + 1);
> +	if (omap3_beagle_get_rev() != OMAP3BEAGLE_BOARD_XM) {
> +		gpio_request(gpio + 1, "EHCI_nOC");
> +		gpio_direction_input(gpio + 1);
> +	}
>
> 	/*
> 	 * TWL4030_GPIO_MAX + 0 == ledA, EHCI nEN_USB_PWR (out, XM active
> @@ -317,6 +318,19 @@ static int beagle_twl_gpio_setup(struct device *dev,
> 	/* TWL4030_GPIO_MAX + 1 == ledB, PMU_STAT (out, active low LED) */
> 	gpio_leds[2].gpio = gpio + TWL4030_GPIO_MAX + 1;
>
> +	/*
> +	 * gpio + 1 on Xm controls the TFP410's enable line (active low)
> +	 * gpio + 2 control varies depending on the board rev as follows:
> +	 * P7/P8 revisions(prototype): Camera EN
> +	 * A2+ revisions (production): LDO (supplies DVI, serial, led blocks)
> +	 */
> +	if (omap3_beagle_get_rev() == OMAP3BEAGLE_BOARD_XM) {
> +		gpio_request(gpio + 1, "nDVI_PWR_EN");
> +		gpio_direction_output(gpio + 1, 0);
> +		gpio_request(gpio + 2, "DVI_LDO_EN");
> +		gpio_direction_output(gpio + 2, 1);

FYI, gpiolib provides gpio_request_one() and gpio_request_array() calls
which make code simpler. I think any new code should use those _and_
do proper error checking.

> +	}
> +
> 	return 0;
> }
>
> -- 
> 1.6.3.3
>