samus: Changes for Proto1b

- disable PP1800_PGOOD internal pullup
- add PP3300_DSW_EN control on PF6, turned on in S5 and off in G3
- change PCH_WAKE_L and PCH_PWRBTN_L to open drain signals
- add PCH_BL_EN interrupt on PM3 for rising edge to put backlight
controller into PWM mode, remove 1 second hook
- add samus-specific extpower handler for AC_PRESENT to buffer the
AC_PRESENT input to the new PCH_ACOK output on PM6.  this is driven
high in S5/S3/S0 when AC_PRESENT is high, otherwise driven low.

BUG=chrome-os-partner:23752
BRANCH=samus
TEST=emerge-samus chromeos-ec

Change-Id: Ie8ab538610e41914212ee1f3a6287b63474fb85b
Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/175281
Reviewed-by: Bill Richardson <wfrichar@chromium.org>

6 files changed, 90 insertions, 25 deletions

diff --git a/board/samus/board.c b/board/samus/board.c
index 9e6b039715..a2e1e14b30 100644
--- a/board/samus/board.c
+++ b/board/samus/board.c
@@ -52,7 +52,7 @@ const struct gpio_info gpio_list[] = {
 	 x86_interrupt},
 	{"PP1200_PGOOD",         LM4_GPIO_H, (1<<6), GPIO_INT_BOTH,
 	 x86_interrupt},
-	{"PP1800_PGOOD",         LM4_GPIO_L, (1<<7), GPIO_PULL_UP|GPIO_INT_BOTH,
+	{"PP1800_PGOOD",         LM4_GPIO_L, (1<<7), GPIO_INT_BOTH,
 	 x86_interrupt},
 	{"VCORE_PGOOD",          LM4_GPIO_C, (1<<6), GPIO_INT_BOTH,
 	 x86_interrupt},
@@ -60,6 +60,8 @@ const struct gpio_info gpio_list[] = {
 	 switch_interrupt},
 	{"WP_L",                 LM4_GPIO_A, (1<<4), GPIO_INT_BOTH,
 	 switch_interrupt},
+	{"PCH_BL_EN",            LM4_GPIO_M, (1<<3), GPIO_INT_RISING,
+	 backlight_interrupt},
 
 	/* Other inputs */
 	{"BOARD_VERSION1",       LM4_GPIO_Q, (1<<5), GPIO_INPUT, NULL},
@@ -78,6 +80,7 @@ const struct gpio_info gpio_list[] = {
 	/* Outputs; all unasserted by default except for reset signals */
 	{"CPU_PROCHOT",          LM4_GPIO_B, (1<<1), GPIO_OUT_LOW, NULL},
 	{"PP1200_EN",            LM4_GPIO_H, (1<<5), GPIO_OUT_LOW, NULL},
+	{"PP3300_DSW_EN",        LM4_GPIO_F, (1<<6), GPIO_OUT_LOW, NULL},
 	{"PP3300_DSW_GATED_EN",  LM4_GPIO_J, (1<<3), GPIO_OUT_LOW, NULL},
 	{"PP3300_LTE_EN",        LM4_GPIO_D, (1<<2), GPIO_OUT_LOW, NULL},
 	{"PP3300_WLAN_EN",       LM4_GPIO_J, (1<<0), GPIO_OUT_LOW, NULL},
@@ -98,14 +101,15 @@ const struct gpio_info gpio_list[] = {
 	 * input until we drive it high.  So can't use open-drain (HI_Z).
 	 */
 	{"PCH_HDA_SDO",          LM4_GPIO_G, (1<<1), GPIO_INPUT, NULL},
-	{"PCH_WAKE_L",           LM4_GPIO_F, (1<<0), GPIO_OUT_HIGH, NULL},
+	{"PCH_WAKE_L",           LM4_GPIO_F, (1<<0), GPIO_ODR_HIGH, NULL},
 	{"PCH_NMI_L",            LM4_GPIO_F, (1<<2), GPIO_ODR_HIGH, NULL},
-	{"PCH_PWRBTN_L",         LM4_GPIO_H, (1<<0), GPIO_OUT_HIGH, NULL},
+	{"PCH_PWRBTN_L",         LM4_GPIO_H, (1<<0), GPIO_ODR_HIGH, NULL},
 	{"PCH_PWROK",            LM4_GPIO_F, (1<<5), GPIO_OUT_LOW, NULL},
 	{"PCH_RCIN_L",           LM4_GPIO_F, (1<<3), GPIO_ODR_HIGH, NULL},
 	{"PCH_SYS_RST_L",        LM4_GPIO_F, (1<<1), GPIO_ODR_HIGH, NULL},
 	{"PCH_SMI_L",            LM4_GPIO_F, (1<<4), GPIO_ODR_HIGH, NULL},
 	{"TOUCHSCREEN_RESET_L",  LM4_GPIO_N, (1<<7), GPIO_OUT_LOW, NULL},
+	{"PCH_ACOK",             LM4_GPIO_M, (1<<6), GPIO_OUT_LOW, NULL},
 #ifndef HEY_USE_BUILTIN_CLKRUN
 	{"LPC_CLKRUN_L",         LM4_GPIO_M, (1<<2), GPIO_ODR_HIGH, NULL},
 #endif
diff --git a/board/samus/board.h b/board/samus/board.h
index ba2d7c7555..c8c9dfda1a 100644
--- a/board/samus/board.h
+++ b/board/samus/board.h
@@ -18,7 +18,6 @@
 #define CONFIG_BOARD_VERSION
 #define CONFIG_CHIPSET_X86
 #define CONFIG_CHIPSET_CAN_THROTTLE
-#define CONFIG_EXTPOWER_GPIO
 #define CONFIG_KEYBOARD_BOARD_CONFIG
 #define CONFIG_KEYBOARD_PROTOCOL_8042
 #define CONFIG_LED_DRIVER_DS2413
@@ -87,6 +86,7 @@ enum gpio_signal {
 	GPIO_VCORE_PGOOD,          /* Power good on core VR */
 	GPIO_RECOVERY_L,           /* Recovery signal from servo */
 	GPIO_WP_L,                 /* Write protect input */
+	GPIO_PCH_BL_EN,            /* PCH backlight input */
 
 	/* Other inputs */
 	GPIO_BOARD_VERSION1,       /* Board version stuffing resistor 1 */
@@ -104,7 +104,8 @@ enum gpio_signal {
 	/* Outputs */
 	GPIO_CPU_PROCHOT,          /* Force CPU to think it's overheated */
 	GPIO_PP1200_EN,            /* Enable 1.20V supply */
-	GPIO_PP3300_DSW_GATED_EN,  /* Enable DSW rails */
+	GPIO_PP3300_DSW_EN,        /* Enable 3.3V DSW rail */
+	GPIO_PP3300_DSW_GATED_EN,  /* Enable 3.3V Gated DSW and core VDD */
 	GPIO_PP3300_LTE_EN,        /* Enable LTE radio */
 	GPIO_PP3300_WLAN_EN,       /* Enable WiFi power */
 	GPIO_PP1050_EN,            /* Enable 1.05V regulator */
@@ -130,6 +131,7 @@ enum gpio_signal {
 	GPIO_PCH_SYS_RST_L,        /* Reset PCH resume power plane logic */
 	GPIO_PCH_SMI_L,            /* System management interrupt to PCH */
 	GPIO_TOUCHSCREEN_RESET_L,  /* Reset touch screen */
+	GPIO_PCH_ACOK,             /* AC present signal buffered to PCH */
 #ifndef HEY_USE_BUILTIN_CLKRUN
 	GPIO_LPC_CLKRUN_L,         /* Dunno. Probably important, though. */
 #endif
diff --git a/board/samus/build.mk b/board/samus/build.mk
index 9f1237d90c..153a280b76 100644
--- a/board/samus/build.mk
+++ b/board/samus/build.mk
@@ -9,4 +9,4 @@
 # the IC is TI Stellaris LM4
 CHIP:=lm4
 
-board-y=board.o power_sequence.o panel.o
+board-y=board.o power_sequence.o panel.o extpower.o
diff --git a/board/samus/extpower.c b/board/samus/extpower.c
new file mode 100644
index 0000000000..6100a83127
--- /dev/null
+++ b/board/samus/extpower.c
@@ -0,0 +1,64 @@
+/* Copyright (c) 2013 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/*
+ * Pure GPIO-based external power detection, buffered to PCH.
+ * Drive high in S5-S0 when AC_PRESENT is high, otherwise drive low.
+ */
+
+#include "chipset.h"
+#include "common.h"
+#include "extpower.h"
+#include "gpio.h"
+#include "hooks.h"
+#include "host_command.h"
+
+int extpower_is_present(void)
+{
+	return gpio_get_level(GPIO_AC_PRESENT);
+}
+
+/**
+ * Deferred function to handle external power change
+ */
+static void extpower_deferred(void)
+{
+	hook_notify(HOOK_AC_CHANGE);
+
+	/* Forward notification to host */
+	if (extpower_is_present())
+		host_set_single_event(EC_HOST_EVENT_AC_CONNECTED);
+	else
+		host_set_single_event(EC_HOST_EVENT_AC_DISCONNECTED);
+}
+DECLARE_DEFERRED(extpower_deferred);
+
+static void extpower_buffer_to_pch(void)
+{
+	if (chipset_in_state(CHIPSET_STATE_HARD_OFF)) {
+		/* Drive low in G3 state */
+		gpio_set_level(GPIO_PCH_ACOK, 0);
+	} else {
+		/* Buffer from extpower in S5+ (where 3.3DSW enabled) */
+		gpio_set_level(GPIO_PCH_ACOK, extpower_is_present());
+	}
+}
+
+void extpower_interrupt(enum gpio_signal signal)
+{
+	extpower_buffer_to_pch();
+
+	/* Trigger deferred notification of external power change */
+	hook_call_deferred(extpower_deferred, 0);
+}
+
+static void extpower_init(void)
+{
+	extpower_buffer_to_pch();
+
+	/* Enable interrupts, now that we've initialized */
+	gpio_enable_interrupt(GPIO_AC_PRESENT);
+}
+DECLARE_HOOK(HOOK_INIT, extpower_init, HOOK_PRIO_DEFAULT);
diff --git a/board/samus/panel.c b/board/samus/panel.c
index 5704179d5d..9b62f0e2c9 100644
--- a/board/samus/panel.c
+++ b/board/samus/panel.c
@@ -61,26 +61,14 @@ DECLARE_HOST_COMMAND(EC_CMD_SWITCH_ENABLE_BKLIGHT,
 		     switch_command_enable_backlight,
 		     EC_VER_MASK(0));
 
-/**
- * Hook to turn backlight PWM mode on if it turns off.
- */
-static void backlight_pwm_mode_hook(void)
+void backlight_interrupt(enum gpio_signal signal)
 {
-	int reg;
-
-	/* Only check if the system is powered. */
-	if (!chipset_in_state(CHIPSET_STATE_ON))
-		return;
-
-	/* Read current command reg to see if it is on. */
-	i2c_read8(I2C_PORT_BACKLIGHT, I2C_ADDR_BACKLIGHT,
-		  LP8555_REG_COMMAND, &reg);
-
-	/* Turn it on if needed. */
-	if (!(reg & LP8555_REG_COMMAND_ON))
-		lp8555_enable_pwm_mode();
+	/*
+	 * PCH indicates it is turning on backlight so we should
+	 * attempt to put the backlight controller into PWM mode.
+	 */
+	lp8555_enable_pwm_mode();
 }
-DECLARE_HOOK(HOOK_SECOND, backlight_pwm_mode_hook, HOOK_PRIO_LAST);
 
 /**
  * Update backlight state.
@@ -100,6 +88,7 @@ DECLARE_HOOK(HOOK_LID_CHANGE, update_backlight, HOOK_PRIO_DEFAULT);
  */
 static void backlight_init(void)
 {
+	gpio_enable_interrupt(GPIO_PCH_BL_EN);
 	update_backlight();
 }
 DECLARE_HOOK(HOOK_INIT, backlight_init, HOOK_PRIO_DEFAULT);
diff --git a/board/samus/power_sequence.c b/board/samus/power_sequence.c
index 2dd2ab50da..f6774f2fdd 100644
--- a/board/samus/power_sequence.c
+++ b/board/samus/power_sequence.c
@@ -138,6 +138,7 @@ enum x86_state x86_chipset_init(void)
 			gpio_set_level(GPIO_PP5000_USB_EN, 0);
 			gpio_set_level(GPIO_PP5000_EN, 0);
 			gpio_set_level(GPIO_PCH_DPWROK, 0);
+			gpio_set_level(GPIO_PP3300_DSW_EN, 0);
 			wireless_enable(0);
 		}
 	}
@@ -191,6 +192,9 @@ enum x86_state x86_handle_state(enum x86_state state)
 		break;
 
 	case X86_G3S5:
+		/* Enable 3.3V DSW */
+		gpio_set_level(GPIO_PP3300_DSW_EN, 1);
+
 		/*
 		 * Wait 10ms after +3VALW good, since that powers VccDSW and
 		 * VccSUS.
@@ -211,7 +215,7 @@ enum x86_state x86_handle_state(enum x86_state state)
 			}
 		}
 
-		/* Turn on 3.3V DSW rail. */
+		/* Turn on 3.3V DSW gated rail for core regulator */
 		gpio_set_level(GPIO_PP3300_DSW_GATED_EN, 1);
 
 		/* Assert DPWROK */
@@ -361,6 +365,8 @@ enum x86_state x86_handle_state(enum x86_state state)
 		gpio_set_level(GPIO_PP1050_EN, 0);
 		gpio_set_level(GPIO_PP3300_DSW_GATED_EN, 0);
 		gpio_set_level(GPIO_PP5000_EN, 0);
+		/* Disable 3.3V DSW */
+		gpio_set_level(GPIO_PP3300_DSW_EN, 0);
 		return X86_G3;
 	}