chgstv2: Check charger power in prevent_power_on.

charge_prevent_power_on() had sections which were gated on the following
CONFIG_* option:

    CONFIG_CHARGER_LIMIT_POWER_THRESH_BAT_PCT

However, the block of code that this gated didn't even take the battery
percentage into account and made it very confusing as to why.

This commit simply changes the CONFIG_* option used to gate to be the
following:

    CONFIG_CHARGER_MIN_POWER_MW_FOR_POWER_ON

This better reflects the checks that were actually being made.

Additionally, this CONFIG_* option is defined by default for boards that
have a chipset task and is initialized to 15W, which is the power that
indicates that the charger is likely to speak USB PD.

BUG=b:76174140
BRANCH=None
TEST=make -j buildall

Change-Id: Ic9158dd7109ce6082c6d00157ff266842363b295
Signed-off-by: Aseda Aboagye <aaboagye@google.com>
Reviewed-on: https://chromium-review.googlesource.com/977431
Commit-Ready: Aseda Aboagye <aaboagye@chromium.org>
Tested-by: Aseda Aboagye <aaboagye@chromium.org>
Reviewed-by: Edward Hill <ecgh@chromium.org>

1 files changed, 16 insertions, 23 deletions

diff --git a/common/charge_state_v2.c b/common/charge_state_v2.c
index 3c8a0d80a6..884daef387 100644
--- a/common/charge_state_v2.c
+++ b/common/charge_state_v2.c
@@ -41,9 +41,6 @@
 #define PRECHARGE_TIMEOUT_US (PRECHARGE_TIMEOUT * SECOND)
 #define LFCC_EVENT_THRESH 5 /* Full-capacity change reqd for host event */
 
-/* Prior to negotiating PD, most PD chargers advertise 15W */
-#define LIKELY_PD_USBC_POWER_MW 15000
-
 static int charge_request(int voltage, int current);
 
 /*
@@ -1821,24 +1818,22 @@ int charge_prevent_power_on(int power_button_pressed)
 		battery_get_params(&params);
 		current_batt_params = &params;
 	}
+
 	/* Require a minimum battery level to power on */
 	if (current_batt_params->is_present != BP_YES ||
 	    current_batt_params->state_of_charge <
 	    CONFIG_CHARGER_MIN_BAT_PCT_FOR_POWER_ON)
 		prevent_power_on = 1;
 
-#ifdef CONFIG_CHARGER_LIMIT_POWER_THRESH_BAT_PCT
-	/*
-	 * Allow power-on if our charger advertises more than
-	 * LIKELY_PD_USBC_POWER_MW since it may speak PD and provide
-	 * sufficient power once we enable PD communication.
-	 */
+#ifdef CONFIG_CHARGER_MIN_POWER_MW_FOR_POWER_ON
+#ifdef CONFIG_CHARGE_MANAGER
+	/* However, we can power on if a sufficient charger is present. */
 	if (prevent_power_on)
 		if (charge_manager_get_power_limit_uw() >=
-		    MIN(LIKELY_PD_USBC_POWER_MW * 1000,
-			CONFIG_CHARGER_LIMIT_POWER_THRESH_CHG_MW * 1000))
+		    CONFIG_CHARGER_MIN_POWER_MW_FOR_POWER_ON * 1000)
 			prevent_power_on = 0;
-#endif
+#endif /* defined(CONFIG_CHARGE_MANAGER) */
+#endif /* defined(CONFIG_CHARGER_MIN_POWER_FOR_POWER_ON) */
 
 	/*
 	 * Factory override: Always allow power on if WP is disabled,
@@ -1861,19 +1856,17 @@ int charge_prevent_power_on(int power_button_pressed)
 #ifdef CONFIG_BATTERY_HW_PRESENT_CUSTOM
 	/*
 	 * If battery is NOT physically present then prevent power on until
-	 * charge manager provides at least LIKELY_PD_USBC_POWER_MW.
+	 * a sufficient charger is present.
 	 */
-	if (extpower_is_present() && battery_hw_present() == BP_NO &&
-	    charge_manager_get_power_limit_uw() <
-#ifdef CONFIG_CHARGER_LIMIT_POWER_THRESH_BAT_PCT
-	    MIN(LIKELY_PD_USBC_POWER_MW * 1000,
-		CONFIG_CHARGER_LIMIT_POWER_THRESH_CHG_MW * 1000))
-#else
-	    (LIKELY_PD_USBC_POWER_MW * 1000))
-#endif
+	if (extpower_is_present() && battery_hw_present() == BP_NO
+#ifdef CONFIG_CHARGER_MIN_POWER_MW_FOR_POWER_ON
+	    && charge_manager_get_power_limit_uw() <
+		CONFIG_CHARGER_MIN_POWER_MW_FOR_POWER_ON * 1000
+#endif /* CONFIG_CHARGER_MIN_POWER_MW_FOR_POWER_ON */
+	    )
 		prevent_power_on = 1;
-#endif
-#endif
+#endif /* CONFIG_BATTERY_HW_PRESENT_CUSTOM */
+#endif /* CONFIG_CHARGE_MANAGER */
 	return prevent_power_on;
 }