Candy: Add touchscreen enable pin control for Elan touchscreen power-on sequence

Candy use TS_EN to enable touchscreen, and TOUCH_RST_L for RESETB signal,
so we need add TOUCHSCREEN_ENABLE control for Elan touchscreen power-on sequence.

BUG=chrome-os-partner:32284
BRANCH=rambi
TEST=manual
 Candy use TS_EN to enable touchscreen, and TOUCH_RST_L for RESETB signal.
Signed-off-by: Bruce Wan <Bruce.Wan@quantatw.com>

Change-Id: Ia1f568302c17ab7ed31220370412b1c27ae5dc2f
Reviewed-on: https://chromium-review.googlesource.com/228983
Tested-by: Bruce Wan <Bruce.Wan@quantatw.com>
Reviewed-by: Mohammed Habibulla <moch@chromium.org>
Commit-Queue: Devin Lu <Devin.Lu@quantatw.com>

4 files changed, 26 insertions, 0 deletions

diff --git a/board/candy/board.c b/board/candy/board.c
index ae6b7054d8..fa90b992bd 100644
--- a/board/candy/board.c
+++ b/board/candy/board.c
@@ -104,6 +104,7 @@ const struct gpio_info gpio_list[] = {
 	{"PPSX_EN",              LM4_GPIO_L, (1<<6), GPIO_OUT_LOW, NULL},
 	{"SUSP_VR_EN",           LM4_GPIO_C, (1<<7), GPIO_OUT_LOW, NULL},
 	{"TOUCHSCREEN_RESET_L",  LM4_GPIO_N, (1<<7), GPIO_OUT_LOW, NULL},
+	{"TOUCHSCREEN_ENABLE",   LM4_GPIO_J, (1<<5), GPIO_OUT_LOW, NULL},
 	{"USB_CTL1",             LM4_GPIO_E, (1<<6), GPIO_OUT_LOW, NULL},
 	{"USB_ILIM_SEL",         LM4_GPIO_E, (1<<5), GPIO_OUT_LOW, NULL},
 	{"USB1_ENABLE",          LM4_GPIO_E, (1<<4), GPIO_OUT_LOW, NULL},
diff --git a/board/candy/board.h b/board/candy/board.h
index 759696cbc5..65b5044ac4 100644
--- a/board/candy/board.h
+++ b/board/candy/board.h
@@ -39,6 +39,7 @@
 #define CONFIG_SCI_GPIO GPIO_PCH_SCI_L
 #define CONFIG_TEMP_SENSOR
 #define CONFIG_TEMP_SENSOR_TMP432
+#define CONFIG_TOUCHSCREEN_ENABLE_CONTROL GPIO_TOUCHSCREEN_ENABLE
 #define CONFIG_USB_PORT_POWER_IN_S3
 #define CONFIG_USB_PORT_POWER_SMART
 #define CONFIG_USB_PORT_POWER_SMART_DEFAULT_MODE USB_CHARGE_MODE_CDP
@@ -124,6 +125,7 @@ enum gpio_signal {
 	GPIO_PPSX_EN,              /* Enable PP1350_PCH_SX, PP1000_PCH_SX */
 	GPIO_SUSP_VR_EN,           /* Enable 1.05V regulator */
 	GPIO_TOUCHSCREEN_RESET_L,  /* Reset touch screen */
+	GPIO_TOUCHSCREEN_ENABLE,   /* Touch screen enable */
 	GPIO_USB_CTL1,             /* USB control signal 1 to both ports */
 	GPIO_USB_ILIM_SEL,         /* USB current limit to both ports */
 	GPIO_USB1_ENABLE,          /* USB port 1 output power enable */
diff --git a/include/config.h b/include/config.h
index 839bc6d9b1..4048733ac1 100755
--- a/include/config.h
+++ b/include/config.h
@@ -780,6 +780,14 @@
 #undef CONFIG_TEMP_SENSOR_POWER_GPIO
 
 /*****************************************************************************/
+
+/*
+ * Some touch screens require additional enable signal for proper power
+ * sequencing.
+ */
+#undef CONFIG_TOUCHSCREEN_ENABLE_CONTROL
+
+/*****************************************************************************/
 /* UART config */
 
 /* Baud rate for UARTs */
diff --git a/power/baytrail.c b/power/baytrail.c
index f6320812bd..87b5f8a4f4 100755
--- a/power/baytrail.c
+++ b/power/baytrail.c
@@ -160,6 +160,11 @@ enum power_state power_handle_state(enum power_state state)
 		 */
 		gpio_set_level(GPIO_TOUCHSCREEN_RESET_L, lid_is_open());
 
+#ifdef CONFIG_TOUCHSCREEN_ENABLE_CONTROL
+		gpio_set_level(CONFIG_TOUCHSCREEN_ENABLE_CONTROL,
+			       lid_is_open());
+#endif
+
 		/* Check for state transitions */
 		if (!power_has_signals(IN_PGOOD_S3)) {
 			/* Required rail went away */
@@ -250,6 +255,9 @@ enum power_state power_handle_state(enum power_state state)
 		 * still closed); it may have been turned off if the lid was
 		 * closed in S3.
 		 */
+#ifdef CONFIG_TOUCHSCREEN_ENABLE_CONTROL
+		gpio_set_level(CONFIG_TOUCHSCREEN_ENABLE_CONTROL, 1);
+#endif
 		gpio_set_level(GPIO_TOUCHSCREEN_RESET_L, 1);
 
 		/* Wait for non-core power rails good */
@@ -259,6 +267,9 @@ enum power_state power_handle_state(enum power_state state)
 			gpio_set_level(GPIO_PP3300_DX_EN, 0);
 			gpio_set_level(GPIO_PP5000_EN, 0);
 			gpio_set_level(GPIO_TOUCHSCREEN_RESET_L, 0);
+#ifdef CONFIG_TOUCHSCREEN_ENABLE_CONTROL
+			gpio_set_level(CONFIG_TOUCHSCREEN_ENABLE_CONTROL, 0);
+#endif
 			return POWER_S3;
 		}
 
@@ -389,6 +400,10 @@ enum power_state power_handle_state(enum power_state state)
 		gpio_set_level(GPIO_ENABLE_TOUCHPAD, 0);
 		gpio_set_level(GPIO_TOUCHSCREEN_RESET_L, 0);
 
+#ifdef CONFIG_TOUCHSCREEN_ENABLE_CONTROL
+		gpio_set_level(CONFIG_TOUCHSCREEN_ENABLE_CONTROL, 0);
+#endif
+
 #ifdef CONFIG_LAN_POWER_S3
 		/* Turn off LAN controller power */
 		gpio_set_level(CONFIG_LAN_POWER_S3, 0);