ryu: rework the workaround for the EN_PP3300 issue

When shutting down the MAX77620 PMIC by asserting its SHDN pin, the
EN_PP3300 output of the PMIC (GPIO3) is not driving low keeping the PP3300
rail up. Workaround that issue by removing the pull-up on EN_PP3300 when
we assert SHDN.

Revert the previous CL 263958 aka "ryu: workaround MAX77620 shutdown issue",
in order to use a better workaround which ensures that the power rails
sequencing at startup

Detect the PP1800 rail going up and down by reading the HPD_IN gpio
state (which has a pull-up tied to PP1800), then enable/disable
EN_PP3300 in sequence.

The code using an interrupt on HPD_IN is enabled only on P5,
and as a downside, it is killing the base charging on those boards.
Indeed HPD_IN(C1) is hijacking the EXTINT1 which used to be connected
to the LID_OPEN (E1) GPIO used for the base detection.

Signed-off-by: Vincent Palatin <vpalatin@chromium.org>

BRANCH=none
BUG=chrome-os-partner:38689
TEST=on both P4 and P5 boards, do various power cycling sequences of the
AP using the "apshutdown" and "powerbtn" commands.

Change-Id: Icad6e9ae6a08d76cbfd19f97dd7c129bf43037d8
Reviewed-on: https://chromium-review.googlesource.com/265186
Trybot-Ready: Vincent Palatin <vpalatin@chromium.org>
Tested-by: Vincent Palatin <vpalatin@chromium.org>
Commit-Queue: Vincent Palatin <vpalatin@chromium.org>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Alec Berg <alecaberg@chromium.org>

4 files changed, 33 insertions, 12 deletions

diff --git a/board/ryu/board.c b/board/ryu/board.c
index f6da9c2653..976c546de2 100644
--- a/board/ryu/board.c
+++ b/board/ryu/board.c
@@ -307,6 +307,16 @@ static void board_init(void)
 
 	/* Enable interrupts on VBUS transitions. */
 	gpio_enable_interrupt(GPIO_CHGR_ACOK);
+
+	/*
+	 * TODO(crosbug.com/p/38689) Workaround for PMIC issue on P5.
+	 * remove when P5 are de-commissioned.
+	 * We are re-using EXTINT1 for the new power sequencing workaround
+	 * this is killing the base closing detection on P5
+	 * we won't charge it.
+	 */
+	if (board_get_version() == 5)
+		gpio_enable_interrupt(GPIO_HPD_IN);
 }
 DECLARE_HOOK(HOOK_INIT, board_init, HOOK_PRIO_DEFAULT);
 
@@ -317,6 +327,16 @@ const struct power_signal_info power_signal_list[] = {
 };
 BUILD_ASSERT(ARRAY_SIZE(power_signal_list) == POWER_SIGNAL_COUNT);
 
+/*
+ * TODO(crosbug.com/p/38689) Workaround for MAX77620 PMIC EN_PP3300 issue.
+ * remove when P5 are de-commissioned.
+ */
+void pp1800_on_off_evt(enum gpio_signal signal)
+{
+	int level = gpio_get_level(signal);
+	gpio_set_level(GPIO_EN_PP3300_RSVD, level);
+}
+
 /* ADC channels */
 const struct adc_t adc_channels[] = {
 	/* Vbus sensing. Converted to mV, /10 voltage divider. */
diff --git a/board/ryu/board.h b/board/ryu/board.h
index 285c598cc1..fa5f6eb888 100644
--- a/board/ryu/board.h
+++ b/board/ryu/board.h
@@ -193,6 +193,9 @@ int board_discharge_on_ac(int enable);
 /* Set the charge current limit. */
 void board_set_charge_limit(int charge_ma);
 
+/* PP1800 transition GPIO interrupt handler */
+void pp1800_on_off_evt(enum gpio_signal signal);
+
 #endif /* !__ASSEMBLER__ */
 
 #endif /* __BOARD_H */
diff --git a/board/ryu/gpio.inc b/board/ryu/gpio.inc
index 816e9e3e68..890c64390d 100644
--- a/board/ryu/gpio.inc
+++ b/board/ryu/gpio.inc
@@ -13,6 +13,13 @@ GPIO_INT(LID_OPEN,             E, 1,  GPIO_INT_BOTH | GPIO_PULL_UP,    lid_inter
 GPIO_INT(CHARGE_DONE,          E, 6,  GPIO_INT_BOTH,                   inductive_charging_interrupt)
 GPIO_INT(AP_IN_SUSPEND,        F, 9,  GPIO_INT_BOTH,                   power_signal_interrupt)
 GPIO_INT(AP_HOLD,              E, 3,  GPIO_INT_BOTH,                   power_signal_interrupt)
+/*
+ * TODO(crosbug.com/p/38689) Workaround for MAX77620 PMIC PP3300 issue
+ * Put back as GPIO_ODR_HIGH for P6+
+ */
+GPIO_INT(HPD_IN,               C, 1,  GPIO_INT_BOTH,                   pp1800_on_off_evt)
+
+/* Interrupt lines not used yet */
 GPIO(BC_TEMP_ALERT_L,      C, 5,  GPIO_INT_FALLING)
 GPIO(LB_INT_L,             E, 7,  GPIO_INT_FALLING | GPIO_PULL_UP)
 GPIO(LIGHTBAR_EN_L,        E, 8,  GPIO_INT_FALLING | GPIO_PULL_UP)
@@ -40,10 +47,11 @@ GPIO(PMIC_PWRON_L,         D, 14, GPIO_ODR_HIGH)
 GPIO(PMIC_WARM_RESET_L,    E, 4,  GPIO_ODR_HIGH)
 GPIO(EN_PP5000,            A, 14, GPIO_OUT_LOW) /* Proto 5+ */
 /*
- * We are missing an external pull-up for EN_PP3300. Pull it up here.
+ * We are missing an external pull-up for EN_PP3300.
+ * This GPIO is used to pull it up through an external 100kOhm.
  * EN_PP3300 is still controlled by PMIC though.
  */
-GPIO(EN_PP3300_RSVD,       E, 13, GPIO_INPUT | GPIO_PULL_UP)
+GPIO(EN_PP3300_RSVD,       E, 13, GPIO_OUT_LOW)
 /* sensor temp output and PMIC reset input */
 GPIO(P5_PMIC_THERM_L,      B, 8,  GPIO_ODR_HIGH)
 /* TODO(crosbug.com/p/38333) remove P4_PMIC_THERM_L */
diff --git a/power/tegra.c b/power/tegra.c
index 2bdba8b5f9..5efd41e61d 100644
--- a/power/tegra.c
+++ b/power/tegra.c
@@ -144,11 +144,6 @@ static void set_ap_reset(int asserted)
  */
 static void set_pmic_pwron(int asserted)
 {
-#ifdef BOARD_RYU
-	/* TODO(crosbug.com/p/38689) Workaround for MAX77620 PMIC issue */
-	if (asserted)
-		gpio_set_flags(GPIO_EN_PP3300_RSVD, GPIO_INPUT | GPIO_PULL_UP);
-#endif /* BOARD_RYU */
 	/* Signal is active-low */
 	gpio_set_level(GPIO_PMIC_PWRON_L, asserted ? 0 : 1);
 }
@@ -163,11 +158,6 @@ static void set_pmic_therm(int asserted)
 {
 	/* Signal is active-low */
 	gpio_set_level(GPIO_PMIC_THERM_L, asserted ? 0 : 1);
-#ifdef BOARD_RYU
-	/* TODO(crosbug.com/p/38689) Workaround for MAX77620 PMIC issue */
-	if (asserted)
-		gpio_set_flags(GPIO_EN_PP3300_RSVD, GPIO_INPUT);
-#endif /* BOARD_RYU */
 }
 
 /**