[U-Boot] [PATCHv1] board: ge: bx50v3: enable backlight on demand

Sebastian Reichel sebastian.reichel at collabora.co.uk
Fri Mar 9 14:41:25 UTC 2018


From: Ian Ray <ian.ray at ge.com>

Enable display backlight only if a message needs to be displayed.
The kernel re-initializes the backlight, which results in some
unwanted artifacts.

Signed-off-by: Ian Ray <ian.ray at ge.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel at collabora.co.uk>
---
 board/ge/bx50v3/bx50v3.c    | 43 ++++++++++++++++++++++++++-----------------
 include/configs/ge_bx50v3.h |  1 +
 2 files changed, 27 insertions(+), 17 deletions(-)

diff --git a/board/ge/bx50v3/bx50v3.c b/board/ge/bx50v3/bx50v3.c
index c7a29185bf49..35efe159d598 100644
--- a/board/ge/bx50v3/bx50v3.c
+++ b/board/ge/bx50v3/bx50v3.c
@@ -786,23 +786,6 @@ int board_late_init(void)
 	add_board_boot_modes(board_boot_modes);
 #endif
 
-#ifdef CONFIG_VIDEO_IPUV3
-	/* We need at least 200ms between power on and backlight on
-	 * as per specifications from CHI MEI */
-	mdelay(250);
-
-	/* enable backlight PWM 1 */
-	pwm_init(0, 0, 0);
-
-	/* duty cycle 5000000ns, period: 5000000ns */
-	pwm_config(0, 5000000, 5000000);
-
-	/* Backlight Power */
-	gpio_direction_output(LVDS_BACKLIGHT_GP, 1);
-
-	pwm_enable(0);
-#endif
-
 	/* board specific pmic init */
 	pmic_init();
 
@@ -843,3 +826,29 @@ int checkboard(void)
 	printf("BOARD: %s\n", CONFIG_BOARD_NAME);
 	return 0;
 }
+
+static int do_backlight_enable(void)
+{
+#ifdef CONFIG_VIDEO_IPUV3
+	/* We need at least 200ms between power on and backlight on
+	 * as per specifications from CHI MEI */
+	mdelay(250);
+
+	/* enable backlight PWM 1 */
+	pwm_init(0, 0, 0);
+
+	/* duty cycle 5000000ns, period: 5000000ns */
+	pwm_config(0, 5000000, 5000000);
+
+	/* Backlight Power */
+	gpio_direction_output(LVDS_BACKLIGHT_GP, 1);
+
+	pwm_enable(0);
+#endif
+}
+
+U_BOOT_CMD(
+       bx50_backlight_enable, 1,      1,      do_backlight_enable,
+       "enable Bx50 backlight",
+       "no parameters"
+);
diff --git a/include/configs/ge_bx50v3.h b/include/configs/ge_bx50v3.h
index cbfe30d536d0..925507fe81f1 100644
--- a/include/configs/ge_bx50v3.h
+++ b/include/configs/ge_bx50v3.h
@@ -128,6 +128,7 @@
 	"swappartitions=" \
 		"setexpr partnum 3 - ${partnum}\0" \
 	"failbootcmd=" \
+		"bx50_backlight_enable; " \
 		"msg=\"Monitor failed to start.  Try again, or contact GE Service for support.\"; " \
 		"echo $msg; " \
 		"setenv stdout vga; " \
-- 
2.16.1



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