apalis-imx8: turn off lcd backlight before os handover
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 GPIO Apalis BKL1 before booting Linux.
Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Reviewed-by: Fabio Estevam <festevam@denx.de>
diff --git a/board/toradex/apalis-imx8/apalis-imx8.c b/board/toradex/apalis-imx8/apalis-imx8.c
index 6f28367..1622900 100644
--- a/board/toradex/apalis-imx8/apalis-imx8.c
+++ b/board/toradex/apalis-imx8/apalis-imx8.c
@@ -182,9 +182,18 @@
}
#if CONFIG_IS_ENABLED(DM_GPIO)
+
+#define BKL1_GPIO IMX_GPIO_NR(1, 10)
+
+static iomux_cfg_t board_gpios[] = {
+ SC_P_LVDS1_GPIO00 | MUX_MODE_ALT(3) | MUX_PAD_CTRL(GPIO_PAD_CTRL),
+};
+
static void board_gpio_init(void)
{
- /* TODO */
+ imx8_iomux_setup_multiple_pads(board_gpios, ARRAY_SIZE(board_gpios));
+
+ gpio_request(BKL1_GPIO, "BKL1_GPIO");
}
#else
static inline void board_gpio_init(void) {}
@@ -202,6 +211,14 @@
}
#endif
+/*
+ * Backlight off before OS handover
+ */
+void board_preboot_os(void)
+{
+ gpio_direction_output(BKL1_GPIO, 0);
+}
+
int checkboard(void)
{
puts("Model: Toradex Apalis iMX8\n");