grunt: Enable LM3630A driver for keyboard backlight

BUG=b:69379749
BRANCH=None
TEST=kblight 100; kblight 50; kblight 0

Change-Id: I003ae1071de0430fe38a48b2e9bccb08207bc019
Signed-off-by: Benjamin Gordon <bmgordon@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/879083
Reviewed-by: Edward Hill <ecgh@chromium.org>
Reviewed-by: Jett Rink <jettrink@chromium.org>

board/grunt/board.c

@@ -17,6 +17,7 @@
 #include "driver/accel_kionix.h"
 #include "driver/accel_kx022.h"
 #include "driver/accelgyro_bmi160.h"
+#include "driver/led/lm3630a.h"
 #include "driver/ppc/sn5s330.h"
 #include "driver/tcpm/anx74xx.h"
 #include "driver/tcpm/ps8xxx.h"
@@ -226,6 +227,13 @@ static void board_chipset_resume(void)
 {
 	/* Allow display backlight to turn on. See above backlight comment */
 	gpio_set_level(GPIO_ENABLE_BACKLIGHT_L, 0);
+
+	/*
+	 * Enable keyboard backlight. This needs to be done here because
+	 * the chip doesn't have power until PP3300_S0 comes up.
+	 */
+	gpio_set_level(GPIO_KB_BL_EN, 1);
+	lm3630a_poweron();
 }
 DECLARE_HOOK(HOOK_CHIPSET_RESUME, board_chipset_resume, HOOK_PRIO_DEFAULT);
 

board/grunt/board.h

@@ -144,6 +144,9 @@
 /* Thermal */
 #define CONFIG_TEMP_SENSOR_SB_TSI
 
+/* KB backlight driver */
+#define CONFIG_LED_DRIVER_LM3630A
+
 /* FIFO size is a power of 2. */
 #define CONFIG_ACCEL_FIFO 1024  /* TODO(teravest): Check this value. */