Revert "eve: Delay charge port selection until VBUS is stable or 1s has passed"

This reverts commit c26996a848d6e2e0e2916e0cbfe716fff532f767.

Reason for revert: Triggering bad behavior with certain docks.
First step is to revert, then we can look at a better workaround.

BUG=chromium:1037765
BRANCH=eve
TEST=none

Original change's description:
> eve: Delay charge port selection until VBUS is stable or 1s has passed
> 
> When a charge port is selected and VBUS is 5V, the inrush current causes
> VBUS to droop which could signal a sink disconnection.
> 
> To mitigate this problem, charge port selection is delayed until VBUS
> is stable or 1s has passed. Before 1s has passed, PD will hopefully have
> negotiated a VBUS voltage of at least 9V.
> 
> This CL is also a workaround for the issue outlined in b:74753447
> 
> Signed-off-by: Sam Hurst <shurst@chromium.org>
> 
> BUG=b:69439094
> BRANCH=None
> TEST=`make -j buildall`
> Manual tested with Belkin Express Dock and Moshi audio adapter.
> Test Belkin with following configuration:
> 
> PORT0:    PORT1:
> Belkin    OPEN
> OPEN      Belkin
> Belkin    Blackcat
> Blackcat  Belkin
> 
> Belkin EC terminal output:
> Port 0:
> [654.645288 TCPC p0 Exit Low Power Mode]
> C0 st14
> C0 st15
> C0 st17
> C0 st18
> C0 st19
> Requested 5000 V 3000 mA (for 900/900 mA)
> C0 st20
> C0 st21
> C0 st22
> C0 st23
> C0 st24
> C0 st23
> C0 st26
> C0 st27
> C0 st28
> C0 st29
> [655.375668 New chg p0]
> C0 st5
> [655.380708 Ramp reset: st1]
> [655.381704 CL: p0 s8 i500 v5000]
> [655.392598 New chg p0]
> [655.393574 Ramp reset: st1]
> [655.394504 CL: p0 s2 i3000 v5000]
> C0 Req [4] 15000mV 3000mA
> [655.512126 New chg p0]
> [655.514456 Ramp reset: st1]
> C0 st715219 CL: p0 s0 ]
> C0 st8
> [655.639762 Ramp reset: st1]
> [655.640301 CL: p0 s0 i3000 v15000]
> [656.688735 AC on]
> [657.385539 Ramp p0 st5 3000mA 3000mA]
> [657.471108 Battery 70% / 7h:36 to empty]
> [659.721858 charge_request(8800mV, 5376mA)]
> [660.973258 charge_request(8800mV, 3712mA)]
> [697.506594 Battery 71% / 1h:1 to full]
> 
> Port 1:
> [729.384242 TCPC p1 Exit Low Power Mode]
> C1 st2
> C1 st3
> C1 st14
> C1 st15
> C1 st17
> C1 st18
> C1 st19
> Requested 5000 V 3000 mA (for 900/900 mA)
> C1 st20
> C1 st21
> C1 st22
> C1 st23
> C1 st24
> C1 st23
> C1 st26
> C1 st27
> C1 st28
> C1 st29
> [730.339719 New chg p1]
> [730.340602 Ramp reset: st1]
> [C1 st5
> 730.341457 CL: p1 s8 i500 v5000]
> [730.356552 New chg p1]
> [730.357311 Ramp reset: st1]
> [730.358095 CL: p1 s2 i3000 v5000]
> C1 Req [4] 15000mV 3000mA
> [730.478577 New chg p1]
> [730.480986 Ramp reset: st1]
> [730.481829 CL:Cp1 s0 i500 v15]
> C1 st8
> [730.607116 Ramp reset: st1]
> [730.607813 CL: p1 s0 i3000 v15000]
> [731.654877 AC on]
> [732.345420 Ramp p1 st5 3000mA 3000mA]
> [732.589802 Battery 71% / 10h:28 to empty]
> [734.340030 charge_request(8800mV, 5376mA)]
> [735.091263 charge_request(8800mV, 3712mA)]
> [767.879314 Battery 72% / 1h:1 to full]
> 
> Tested Moshi with followint configuration:
> 
> Port0:           Port1:
> Moshi-pwr        OPEN
> OPEN             Moshi-pwr
> Moshi-pwr        Blackcat
> Blackcat         Moshi-pwr
> Moshi-audio      OPEN
> OPEN             Moshi-audio
> Moshi-audio      Blackcat
> Blackcat         Moshi-pwr
> Moshi-pwr-audio  OPEN
> OPEN             Moshi-pwr-audio
> Moshi-pwr-audio  Blackcat
> Blackcat         Moshi-pwr-audio
> 
> Moshi EC terminal output:
> 
> [2330.883267 TCPC p0 Low Power Mode]
> [2330.883664 TCPC p0 reset!]
> [2330.916049 TCPC p0 Low Power Mode]
> [2330.916475 TCPC p0 reset!]
> [2330.934010 TCPC p0 Exit Low Power Mode]
> C0 st14
> C0 st15
> C0 st17
> C0 st18
> C0 st19
> Requested 5000 V 3000 mA (for 3000/3000 mA)
> C0 st20
> C0 st21
> C0 st22
> C0 st23
> C0 st24
> C0 st23
> C0 st26
> C0 st23
> C0 st27
> C0 st28
> C0 st29
> [2332.398132 New chg p0]
> [2332.398883 Ramp reset: st1]
> [2332.399745 CL: p0 s8 i500 v5000]
> C0 st5
> [2332.476132 New chg p0]
> [2332.476933 Ramp reset: st1]
> [2332.477705 CL: p0 s2 i3000 v5000]
> C0 Req [4] 15000mV 2970mA
> [2332.493597 New cCg p0C0 st7
> ]
> [2332[2332.5001C0 st8
> [2332.674727 Ramp reset: st1]
> [2332.675510 CL: p0 s0 i2970 v15000]
> [2333.668216 AC on]
> [2334.403481 Ramp p0 st5 2970mA 2970mA]
> [2334.450155 Battery 80% / 11h:18 to empty]
> [2335.448877 charge_request(8800mV, 5376mA)]
> [2336.699875 charge_request(8800mV, 3712mA)]
> [2356.466385 Battery 81% / 1h:1 to full]
> 
> Change-Id: Iba909c252094c0e5ca4cf974aabcfe1eaf002efd
> Reviewed-on: https://chromium-review.googlesource.com/1130000
> Commit-Ready: Sam Hurst <shurst@google.com>
> Tested-by: Sam Hurst <shurst@google.com>
> Reviewed-by: Duncan Laurie <dlaurie@google.com>
> (cherry picked from commit 347d2912e71a4e1c7f962448ac22cd2c3d3e4866)
> Reviewed-on: https://chromium-review.googlesource.com/c/1419777
> Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
> Commit-Queue: Todd Broch <tbroch@chromium.org>
> Tested-by: Todd Broch <tbroch@chromium.org>

Bug: b:69439094
Change-Id: Ic31f8f13fd8a9ee5b036625e0ff617acf2679066
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2013824
Reviewed-by: Duncan Laurie <dlaurie@google.com>
Commit-Queue: Duncan Laurie <dlaurie@google.com>
Tested-by: Duncan Laurie <dlaurie@google.com>

3 files changed, 0 insertions, 125 deletions

diff --git a/board/eve/board.h b/board/eve/board.h
index 0b3f43be60..8a30d23281 100644
--- a/board/eve/board.h
+++ b/board/eve/board.h
@@ -170,7 +170,6 @@
 #define CONFIG_USB_PD_DISCHARGE_TCPC
 #define CONFIG_USB_PD_DUAL_ROLE
 #define CONFIG_USB_PD_DUAL_ROLE_AUTO_TOGGLE
-#define CONFIG_BD9995X_DELAY_INPUT_PORT_SELECT
 #define CONFIG_USB_PD_LOGGING
 #define CONFIG_USB_PD_LOG_SIZE 512
 #define CONFIG_USB_PD_MAX_SINGLE_SOURCE_CURRENT TYPEC_RP_3A0
diff --git a/driver/charger/bd9995x.c b/driver/charger/bd9995x.c
index 88cc2f7971..115e9751ef 100644
--- a/driver/charger/bd9995x.c
+++ b/driver/charger/bd9995x.c
@@ -35,37 +35,6 @@
 /* Console output macros */
 #define CPRINTS(format, args...) cprints(CC_CHARGER, format, ## args)
 
-#ifdef CONFIG_BD9995X_DELAY_INPUT_PORT_SELECT
-/*
- * Used in a check to determine if VBUS is within the
- * range of some VOLTAGE +/- VBUS_DELTA, where voltage
- * is measured in mV.
- */
-#define VBUS_DELTA 1000
-
-/* VBUS is debounced if it's stable for this length of time */
-#define VBUS_MSEC (100*MSEC)
-
-/* VBUS debouncing sample interval */
-#define VBUS_CHECK_MSEC (10*MSEC)
-
-/* Time to wait before VBUS debouncing begins */
-#define STABLE_TIMEOUT (500*MSEC)
-
-/* Maximum time to wait until VBUS is debounced */
-#define DEBOUNCE_TIMEOUT (500*MSEC)
-
-enum vstate {START, STABLE, DEBOUNCE};
-static enum vstate vbus_state;
-
-static int vbus_voltage;
-static uint64_t debounce_time;
-static uint64_t vbus_timeout;
-static int port_update;
-static int select_update;
-static int select_input_port_update;
-#endif
-
 /* Charger parameters */
 static const struct charger_info bd9995x_charger_info = {
 	.name         = CHARGER_NAME,
@@ -1066,12 +1035,7 @@ int bd9995x_is_vbus_provided(enum bd9995x_charge_port port)
 	return !!reg;
 }
 
-#ifdef CONFIG_BD9995X_DELAY_INPUT_PORT_SELECT
-static int bd9995x_select_input_port_private(enum bd9995x_charge_port port,
-								int select)
-#else
 int bd9995x_select_input_port(enum bd9995x_charge_port port, int select)
-#endif
 {
 	int rv;
 	int reg;
@@ -1116,49 +1080,6 @@ select_input_port_exit:
 	return rv;
 }
 
-#ifdef CONFIG_BD9995X_DELAY_INPUT_PORT_SELECT
-int bd9995x_select_input_port(enum bd9995x_charge_port port, int select)
-{
-	port_update = port;
-	select_update = select;
-	vbus_state = START;
-	select_input_port_update = 1;
-	task_wake(TASK_ID_USB_CHG);
-
-	return EC_SUCCESS;
-}
-
-static inline int bd9995x_vbus_test(int value, int limit)
-{
-	uint32_t hi_value = limit + VBUS_DELTA;
-	uint32_t lo_value = limit - VBUS_DELTA;
-
-	return ((value > lo_value) && (value < hi_value));
-}
-
-static int bd9995x_vbus_debounce(enum bd9995x_charge_port port)
-{
-	int vbus_reg;
-	int voltage;
-
-	vbus_reg = (port == BD9995X_CHARGE_PORT_VBUS) ?
-		BD9995X_CMD_VBUS_VAL : BD9995X_CMD_VCC_VAL;
-	if (ch_raw_read16(vbus_reg, &voltage, BD9995X_EXTENDED_COMMAND))
-		voltage = 0;
-
-	if (!bd9995x_vbus_test(voltage, vbus_voltage)) {
-		vbus_voltage = voltage;
-		debounce_time = get_time().val + VBUS_MSEC;
-	} else {
-		if (get_time().val >= debounce_time)
-			return 1;
-	}
-
-	return 0;
-}
-#endif
-
-
 #ifdef CONFIG_CHARGER_BATTERY_TSENSE
 int bd9995x_get_battery_temp(int *temp_ptr)
 {
@@ -1257,11 +1178,6 @@ void usb_charger_task(void *u)
 	int vbus_reg, voltage;
 #endif
 
-#ifdef CONFIG_BD9995X_DELAY_INPUT_PORT_SELECT
-	select_input_port_update = 0;
-	vbus_voltage = 0;
-#endif
-
 	for (port = 0; port < CONFIG_USB_PD_PORT_COUNT; port++) {
 		bc12_detected_type[port] = CHARGE_SUPPLIER_NONE;
 		bd9995x_enable_vbus_detect_interrupts(port, 1);
@@ -1337,43 +1253,6 @@ void usb_charger_task(void *u)
 		}
 
 		initialized = 1;
-#ifdef CONFIG_BD9995X_DELAY_INPUT_PORT_SELECT
-/*
- * When a charge port is selected and VBUS is 5V, the inrush current on some
- * devices causes VBUS to droop, which could signal a sink disconnection.
- *
- * To mitigate the problem, charge port selection is delayed until VBUS
- * is stable or one second has passed. Hopefully PD has negotiated a VBUS
- * voltage of at least 9V before the one second timeout.
- */
-	if (select_input_port_update) {
-		sleep_usec = VBUS_CHECK_MSEC;
-		changed = 0;
-
-		switch (vbus_state) {
-		case START:
-			vbus_timeout = get_time().val + STABLE_TIMEOUT;
-			vbus_state = STABLE;
-			break;
-		case STABLE:
-			if (get_time().val > vbus_timeout) {
-				vbus_state = DEBOUNCE;
-				vbus_timeout = get_time().val +
-							DEBOUNCE_TIMEOUT;
-			}
-			break;
-		case DEBOUNCE:
-			if (bd9995x_vbus_debounce(port_update) ||
-					get_time().val > vbus_timeout) {
-				select_input_port_update = 0;
-				bd9995x_select_input_port_private(
-						port_update, select_update);
-			}
-			break;
-		}
-	}
-#endif
-
 		/*
 		 * Re-read interrupt registers immediately if we got an
 		 * interrupt. We're dealing with multiple independent
diff --git a/include/config.h b/include/config.h
index 09bf981a4f..5e31ad1d8f 100644
--- a/include/config.h
+++ b/include/config.h
@@ -2389,9 +2389,6 @@
 /* Define if this board can used TCPC-controlled DRP toggle */
 #undef CONFIG_USB_PD_DUAL_ROLE_AUTO_TOGGLE
 
-/* Define to reduces VBUS droop caused by inrush current during charging */
-#undef CONFIG_BD9995X_DELAY_INPUT_PORT_SELECT
-
 /* Initial DRP / toggle policy */
 #define CONFIG_USB_PD_INITIAL_DRP_STATE PD_DRP_TOGGLE_OFF