[U-Boot] [PATCH] board: toradex: turn off lcd backlight before OS handover

Marcel Ziswiler marcel.ziswiler at toradex.com
Wed Nov 14 22:52:39 UTC 2018


On Fri, 2018-10-26 at 14:29 +0200, Philippe Schenker wrote:
> From: Gerard Salvatella <gerard.salvatella at toradex.com>
> 
> U-Boot typically tears down the display controller before handing
> control over to Linux. On LCD displays disabling pixel clock leads to
> a
> fading out effect with vertical/horizontal lines. Make sure to
> disable
> back light before booting Linux.
> 
> Signed-off-by: Gerard Salvatella <gerard.salvatella at toradex.com>
> Signed-off-by: Philippe Schenker <philippe.schenker at toradex.com>

Acked-by: Marcel Ziswiler <marcel.ziswiler at toradex.com>

> ---
>  board/toradex/apalis-tk1/apalis-tk1.c     |  9 +++++++++
>  board/toradex/apalis_imx6/apalis_imx6.c   |  9 +++++++++
>  board/toradex/apalis_t30/apalis_t30.c     |  9 +++++++++
>  board/toradex/colibri_imx6/colibri_imx6.c |  9 +++++++++
>  board/toradex/colibri_imx7/colibri_imx7.c |  9 +++++++++
>  board/toradex/colibri_t20/colibri_t20.c   |  9 +++++++++
>  board/toradex/colibri_t30/colibri_t30.c   |  9 +++++++++
>  board/toradex/colibri_vf/colibri_vf.c     | 12 +++++++++++-
>  8 files changed, 74 insertions(+), 1 deletion(-)
> 
> diff --git a/board/toradex/apalis-tk1/apalis-tk1.c
> b/board/toradex/apalis-tk1/apalis-tk1.c
> index d6a736d8aa..b87e9e7a3e 100644
> --- a/board/toradex/apalis-tk1/apalis-tk1.c
> +++ b/board/toradex/apalis-tk1/apalis-tk1.c
> @@ -240,3 +240,12 @@ void tegra_pcie_board_port_reset(struct
> tegra_pcie_port *port)
>  	}
>  }
>  #endif /* CONFIG_PCI_TEGRA */
> +
> +/*
> + * Backlight off before OS handover
> + */
> +void board_preboot_os(void)
> +{
> +	gpio_request(TEGRA_GPIO(BB, 5), "BL_ON");
> +	gpio_direction_output(TEGRA_GPIO(BB, 5), 0);
> +}
> diff --git a/board/toradex/apalis_imx6/apalis_imx6.c
> b/board/toradex/apalis_imx6/apalis_imx6.c
> index 368db9c488..d11207c7f4 100644
> --- a/board/toradex/apalis_imx6/apalis_imx6.c
> +++ b/board/toradex/apalis_imx6/apalis_imx6.c
> @@ -745,6 +745,15 @@ static void setup_display(void)
>  	gpio_direction_output(RGB_BACKLIGHTPWM_OE, 0);
>  	gpio_direction_output(RGB_BACKLIGHT_GP, 1);
>  }
> +
> +/*
> + * Backlight off before OS handover
> + */
> +void board_preboot_os(void)
> +{
> +	gpio_direction_output(RGB_BACKLIGHTPWM_GP, 1);
> +	gpio_direction_output(RGB_BACKLIGHT_GP, 0);
> +}
>  #endif /* defined(CONFIG_VIDEO_IPUV3) */
>  
>  int board_early_init_f(void)
> diff --git a/board/toradex/apalis_t30/apalis_t30.c
> b/board/toradex/apalis_t30/apalis_t30.c
> index ace9c5b168..df9bc8e707 100644
> --- a/board/toradex/apalis_t30/apalis_t30.c
> +++ b/board/toradex/apalis_t30/apalis_t30.c
> @@ -164,3 +164,12 @@ void tegra_pcie_board_port_reset(struct
> tegra_pcie_port *port)
>  #endif /* CONFIG_APALIS_T30_PCIE_EVALBOARD_INIT */
>  }
>  #endif /* CONFIG_PCI_TEGRA */
> +
> +/*
> + * Backlight off before OS handover
> + */
> +void board_preboot_os(void)
> +{
> +	gpio_request(TEGRA_GPIO(V, 2), "BKL1_ON");
> +	gpio_direction_output(TEGRA_GPIO(V, 2), 0);
> +}
> diff --git a/board/toradex/colibri_imx6/colibri_imx6.c
> b/board/toradex/colibri_imx6/colibri_imx6.c
> index 68c0c02a8a..17876f27e9 100644
> --- a/board/toradex/colibri_imx6/colibri_imx6.c
> +++ b/board/toradex/colibri_imx6/colibri_imx6.c
> @@ -622,6 +622,15 @@ static void setup_display(void)
>  	gpio_direction_output(RGB_BACKLIGHTPWM_GP, 0);
>  	gpio_direction_output(RGB_BACKLIGHT_GP, 1);
>  }
> +
> +/*
> + * Backlight off before OS handover
> + */
> +void board_preboot_os(void)
> +{
> +	gpio_direction_output(RGB_BACKLIGHTPWM_GP, 1);
> +	gpio_direction_output(RGB_BACKLIGHT_GP, 0);
> +}
>  #endif /* defined(CONFIG_VIDEO_IPUV3) */
>  
>  int board_early_init_f(void)
> diff --git a/board/toradex/colibri_imx7/colibri_imx7.c
> b/board/toradex/colibri_imx7/colibri_imx7.c
> index a4c99626b4..be027afd10 100644
> --- a/board/toradex/colibri_imx7/colibri_imx7.c
> +++ b/board/toradex/colibri_imx7/colibri_imx7.c
> @@ -182,6 +182,15 @@ static int setup_lcd(void)
>  }
>  #endif
>  
> +/*
> + * Backlight off before OS handover
> + */
> +void board_preboot_os(void)
> +{
> +	gpio_direction_output(GPIO_PWM_A, 1);
> +	gpio_direction_output(GPIO_BL_ON, 0);
> +}
> +
>  #ifdef CONFIG_FEC_MXC
>  static iomux_v3_cfg_t const fec1_pads[] = {
>  #ifndef CONFIG_COLIBRI_IMX7_EXT_PHYCLK
> diff --git a/board/toradex/colibri_t20/colibri_t20.c
> b/board/toradex/colibri_t20/colibri_t20.c
> index 5dd0f288ed..e0b27e92f8 100644
> --- a/board/toradex/colibri_t20/colibri_t20.c
> +++ b/board/toradex/colibri_t20/colibri_t20.c
> @@ -150,4 +150,13 @@ void pin_mux_display(void)
>  	pinmux_set_func(PMUX_PINGRP_SDC, PMUX_FUNC_PWM);
>  	pinmux_tristate_disable(PMUX_PINGRP_SDC);
>  }
> +
> +/*
> + * Backlight off before OS handover
> + */
> +void board_preboot_os(void)
> +{
> +	gpio_request(TEGRA_GPIO(T, 4), "BL_ON");
> +	gpio_direction_output(TEGRA_GPIO(T, 4), 0);
> +}
>  #endif
> diff --git a/board/toradex/colibri_t30/colibri_t30.c
> b/board/toradex/colibri_t30/colibri_t30.c
> index 8ea96188f6..b6b00e3860 100644
> --- a/board/toradex/colibri_t30/colibri_t30.c
> +++ b/board/toradex/colibri_t30/colibri_t30.c
> @@ -66,3 +66,12 @@ void pin_mux_usb(void)
>  	udelay(5);
>  	gpio_set_value(TEGRA_GPIO(DD, 0), 1);
>  }
> +
> +/*
> + * Backlight off before OS handover
> + */
> +void board_preboot_os(void)
> +{
> +	gpio_request(TEGRA_GPIO(V, 2), "BL_ON");
> +	gpio_direction_output(TEGRA_GPIO(V, 2), 0);
> +}
> diff --git a/board/toradex/colibri_vf/colibri_vf.c
> b/board/toradex/colibri_vf/colibri_vf.c
> index 4db1757469..176c5201f9 100644
> --- a/board/toradex/colibri_vf/colibri_vf.c
> +++ b/board/toradex/colibri_vf/colibri_vf.c
> @@ -38,8 +38,9 @@ DECLARE_GLOBAL_DATA_PTR;
>  #define ENET_PAD_CTRL	(PAD_CTL_PUS_47K_UP |
> PAD_CTL_SPEED_HIGH | \
>  			PAD_CTL_DSE_50ohm | PAD_CTL_OBE_IBE_ENABLE)
>  
> -#define USB_PEN_GPIO           83
> +#define USB_PEN_GPIO		83
>  #define USB_CDET_GPIO		102
> +#define PTC0_GPIO_45		45
>  
>  static struct ddrmc_cr_setting colibri_vf_cr_settings[] = {
>  	/* levelling */
> @@ -640,3 +641,12 @@ int board_usb_phy_mode(int port)
>  	}
>  }
>  #endif
> +
> +/*
> + * Backlight off before OS handover
> + */
> +void board_preboot_os(void)
> +{
> +	gpio_request(PTC0_GPIO_45, "BL_ON");
> +	gpio_direction_output(PTC0_GPIO_45, 0);
> +}


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