servo_v4p1: Add DUT Charge Through functionality

This functionality is only available in RO and
enables the servo V4.1 to charge the DUT.

BRANCH=none
BUG=b:146793000
TEST=make -j buildall

Signed-off-by: Sam Hurst <shurst@google.com>
Change-Id: I317d02081b935d69af712c6189634496f56110f0
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2216404
Reviewed-by: Wai-Hong Tam <waihong@google.com>
(cherry picked from commit 48a55c8b351bc10e5637e90814293a4b7869ac84)
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2332242

4 files changed, 125 insertions, 0 deletions

diff --git a/board/servo_v4p1/board.c b/board/servo_v4p1/board.c
index cc6629547d..e8763766cb 100644
--- a/board/servo_v4p1/board.c
+++ b/board/servo_v4p1/board.c
@@ -7,6 +7,7 @@
 #include "adc.h"
 #include "adc_chip.h"
 #include "ccd_measure_sbu.h"
+#include "chg_control.h"
 #include "common.h"
 #include "console.h"
 #include "ec_version.h"
@@ -330,6 +331,9 @@ static void board_init(void)
 	gpio_enable_interrupt(GPIO_USBH_I2C_BUSY_INT);
 	gpio_enable_interrupt(GPIO_BC12_INT_ODL);
 
+	/* Disable power to DUT by default */
+	chg_power_select(CHG_POWER_OFF);
+
 	/* Start SuzyQ detection */
 	start_ccd_meas_sbu_cycle();
 #endif /* SECTION_IS_RO */
diff --git a/board/servo_v4p1/build.mk b/board/servo_v4p1/build.mk
index 321c911871..c3161a9c67 100644
--- a/board/servo_v4p1/build.mk
+++ b/board/servo_v4p1/build.mk
@@ -20,5 +20,6 @@ board-y+=ioexpanders.o
 # These files are compiled into RO only
 board-ro+=ccd_measure_sbu.o
 board-ro+=pathsel.o
+board-ro+=chg_control.o
 
 all_deps=$(patsubst ro,,$(def_all_deps))
diff --git a/board/servo_v4p1/chg_control.c b/board/servo_v4p1/chg_control.c
new file mode 100644
index 0000000000..cddd8efc69
--- /dev/null
+++ b/board/servo_v4p1/chg_control.c
@@ -0,0 +1,78 @@
+/* Copyright 2020 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.
+ */
+
+#include "chg_control.h"
+#include "gpio.h"
+#include "ioexpanders.h"
+#include "registers.h"
+#include "timer.h"
+
+#define CHG_P5V_POWER  0
+#define CHG_VBUS_POWER 1
+
+void chg_reset(void)
+{
+	/* Disconnect DUT Power */
+	chg_power_select(CHG_POWER_OFF);
+
+	/* Disconnect CHG CC1(Rd) and CC2(Rd) */
+	chg_attach_cc_rds(0);
+
+	msleep(100);
+
+	/* Connect CHG CC1(Rd) and CC2(Rd) to detect charger */
+	chg_attach_cc_rds(1);
+}
+
+void chg_power_select(enum chg_power_select_t type)
+{
+	switch (type) {
+	case CHG_POWER_OFF:
+		dut_chg_en(0);
+		vbus_dischrg_en(1);
+		break;
+	case CHG_POWER_PP5000:
+		vbus_dischrg_en(0);
+		host_or_chg_ctl(CHG_P5V_POWER);
+		dut_chg_en(1);
+		break;
+	case CHG_POWER_VBUS:
+		vbus_dischrg_en(0);
+		host_or_chg_ctl(CHG_VBUS_POWER);
+		dut_chg_en(1);
+		break;
+	}
+}
+
+void chg_attach_cc_rds(bool en)
+{
+	if (en) {
+		/*
+		 * Configure USB_CHG_CC1_MCU and USB_CHG_CC2_MCU as
+		 * ANALOG input
+		 */
+		STM32_GPIO_MODER(GPIO_A) = (STM32_GPIO_MODER(GPIO_A)
+			| (3 << (2*2)) | /* PA2 in ANALOG mode */
+			  (3 << (2*4))); /* PA4 in ANALOG mode */
+	} else {
+		/*
+		 * Configure USB_CHG_CC1_MCU and USB_CHG_CC2_MCU as GPIO and
+		 * drive high to trigger disconnect.
+		 * NOTE: The CC line has an external fixed Rd pull-down.
+		 * Driving the CC line High overrides the pull down and this
+		 * triggers a disconnection.
+		 */
+		/* Set level high */
+		gpio_set_level(GPIO_USB_CHG_CC1_MCU, 1);
+		gpio_set_level(GPIO_USB_CHG_CC2_MCU, 1);
+
+		/* Disable Analog mode and Enable GPO */
+		STM32_GPIO_MODER(GPIO_A) = (STM32_GPIO_MODER(GPIO_A)
+			& ~(3 << (2*2) | /* PA2 disable ADC */
+			    3 << (2*4))) /* PA4 disable ADC */
+			|  (1 << (2*2) | /* Set as GPO */
+			    1 << (2*4)); /* Set as GPO */
+	}
+}
diff --git a/board/servo_v4p1/chg_control.h b/board/servo_v4p1/chg_control.h
new file mode 100644
index 0000000000..8b81708ccc
--- /dev/null
+++ b/board/servo_v4p1/chg_control.h
@@ -0,0 +1,42 @@
+/* Copyright 2020 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.
+ */
+
+#ifndef __CROS_EC_CHG_CONTROL_H
+#define __CROS_EC_CHG_CONTROL_H
+
+#include <stdbool.h>
+
+enum chg_cc_t {
+	CHG_OPEN,
+	CHG_CC1,
+	CHG_CC2
+};
+
+enum chg_power_select_t {
+	CHG_POWER_OFF,
+	CHG_POWER_PP5000,
+	CHG_POWER_VBUS,
+};
+
+/*
+ * Triggers a disconnect and reconnect on the DUT Charger port
+ */
+void chg_reset(void);
+
+/*
+ * Disables or selects the DUT Charger Power source
+ *
+ * @param type Power source used for DUT
+ */
+void chg_power_select(enum chg_power_select_t type);
+
+/*
+ * Attaches or Removes the DUT Charger Ports CC1 and CC2 Rd resistors
+ *
+ * @param en True the CC RDs are attached else they are removed
+ */
+void chg_attach_cc_rds(bool en);
+
+#endif /* __CROS_EC_CHG_CONTROL_H */