lucid: add support to detect BC1.2 suppliers

Use built-in USB periperal to detect BC1.2 suppliers and update the
charge manager.

BUG=chrome-os-partner:48658
BRANCH=None
TEST=manual for lucid. Use a samus as the supplier, and insert the
charger into Lucid. Verify that it identifies it as SDP. Use a wall
charger and verify that Lucid identifies it as DCP.

Change-Id: I7842e9f75874f727837df5bfc28690662caf821c
Signed-off-by: Mary Ruthven <mruthven@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/329236
Reviewed-by: Shawn N <shawnn@chromium.org>

7 files changed, 138 insertions, 24 deletions

diff --git a/board/lucid/board.c b/board/lucid/board.c
index d82467bd7e..a536153b42 100644
--- a/board/lucid/board.c
+++ b/board/lucid/board.c
@@ -8,6 +8,7 @@
 #include "adc_chip.h"
 #include "charge_manager.h"
 #include "charge_state.h"
+#include "charger_detect.h"
 #include "common.h"
 #include "console.h"
 #include "extpower.h"
@@ -18,9 +19,11 @@
 #include "registers.h"
 #include "task.h"
 #include "usb_charge.h"
+#include "usb_pd.h"
 #include "util.h"
 
 #define CPRINTS(format, args...) cprints(CC_USBCHARGE, format, ## args)
+#define USB_CHG_DETECT_DELAY_US 5000
 
 void board_config_pre_init(void)
 {
@@ -40,6 +43,52 @@ void board_config_pre_init(void)
 	STM32_SYSCFG_CFGR1 |= (1 << 9) | (1 << 10);
 }
 
+static void reset_charge(int port)
+{
+	struct charge_port_info charge_none;
+
+	charge_none.voltage = USB_CHARGER_VOLTAGE_MV;
+	charge_none.current = 0;
+	charge_manager_update_charge(CHARGE_SUPPLIER_PROPRIETARY,
+				     port,
+				     &charge_none);
+	charge_manager_update_charge(CHARGE_SUPPLIER_BC12_CDP,
+				     port,
+				     &charge_none);
+	charge_manager_update_charge(CHARGE_SUPPLIER_BC12_DCP,
+				     port,
+				     &charge_none);
+	charge_manager_update_charge(CHARGE_SUPPLIER_BC12_SDP,
+				     port,
+				     &charge_none);
+	charge_manager_update_charge(CHARGE_SUPPLIER_OTHER,
+				     port,
+				     &charge_none);
+}
+
+static void usb_charger_bc12_detect(void)
+{
+	int type;
+	struct charge_port_info charge;
+
+	type = charger_detect_get_device_type();
+	if (gpio_get_level(GPIO_AC_PRESENT) && type) {
+		charge.voltage = USB_CHARGER_VOLTAGE_MV;
+		if (type == CHARGE_SUPPLIER_BC12_CDP)
+			charge.current = 1500;
+		else
+			charge.current = 500;
+
+		charge_manager_update_charge(type, 0, &charge);
+	} else
+		reset_charge(0);
+
+
+	/* notify host of power info change */
+	pd_send_host_event(PD_EVENT_POWER_CHANGE);
+}
+DECLARE_DEFERRED(usb_charger_bc12_detect);
+
 static void update_vbus_supplier(int vbus_level)
 {
 	struct charge_port_info charge;
@@ -56,6 +105,7 @@ void vbus_evt(enum gpio_signal signal)
 	 * lucid only has one port and charging is always enabled.
 	 */
 
+	hook_call_deferred(usb_charger_bc12_detect, USB_CHG_DETECT_DELAY_US);
 	update_vbus_supplier(gpio_get_level(signal));
 
 	task_wake(TASK_ID_PD_C0);
@@ -95,32 +145,10 @@ const unsigned int i2c_ports_used = ARRAY_SIZE(i2c_ports);
 static void board_init(void)
 {
 	int i;
-	struct charge_port_info charge_none;
 
 	/* Initialize all BC1.2 charge suppliers to 0 */
-	/*
-	 * TODO: use built-in USB peripheral to detect BC1.2 suppliers an
-	 * update charge manager.
-	 */
-	charge_none.voltage = USB_CHARGER_VOLTAGE_MV;
-	charge_none.current = 0;
-	for (i = 0; i < CONFIG_USB_PD_PORT_COUNT; i++) {
-		charge_manager_update_charge(CHARGE_SUPPLIER_PROPRIETARY,
-					     i,
-					     &charge_none);
-		charge_manager_update_charge(CHARGE_SUPPLIER_BC12_CDP,
-					     i,
-					     &charge_none);
-		charge_manager_update_charge(CHARGE_SUPPLIER_BC12_DCP,
-					     i,
-					     &charge_none);
-		charge_manager_update_charge(CHARGE_SUPPLIER_BC12_SDP,
-					     i,
-					     &charge_none);
-		charge_manager_update_charge(CHARGE_SUPPLIER_OTHER,
-					     i,
-					     &charge_none);
-	}
+	for (i = 0; i < CONFIG_USB_PD_PORT_COUNT; i++)
+		reset_charge(i);
 
 	/* Enable charge status interrupt */
 	gpio_enable_interrupt(GPIO_CHARGE_STATUS);
diff --git a/board/lucid/board.h b/board/lucid/board.h
index f9fd68c5b1..2163d28517 100644
--- a/board/lucid/board.h
+++ b/board/lucid/board.h
@@ -50,6 +50,7 @@
 #define CONFIG_LOW_POWER_IDLE
 #define CONFIG_LTO
 #define CONFIG_STM_HWTIMER32
+#define CONFIG_STM32_CHARGER_DETECT
 #undef  CONFIG_TASK_PROFILING
 #define CONFIG_USB_POWER_DELIVERY
 #define CONFIG_USB_PD_ALT_MODE
diff --git a/chip/stm32/build.mk b/chip/stm32/build.mk
index 53b48b6ab5..6878c76065 100644
--- a/chip/stm32/build.mk
+++ b/chip/stm32/build.mk
@@ -50,6 +50,7 @@ chip-$(CHIP_FAMILY_STM32F0)+=flash-f.o
 chip-$(CHIP_FAMILY_STM32F3)+=flash-f.o
 endif
 chip-$(CONFIG_ADC)+=adc-$(CHIP_FAMILY).o
+chip-$(CONFIG_STM32_CHARGER_DETECT)+=charger_detect.o
 chip-$(CONFIG_DEBUG_PRINTF)+=debug_printf.o
 chip-$(CONFIG_PWM)+=pwm.o
 chip-$(CONFIG_USB)+=usb.o usb-$(CHIP_FAMILY).o usb_endpoints.o
diff --git a/chip/stm32/charger_detect.c b/chip/stm32/charger_detect.c
new file mode 100644
index 0000000000..b32b9f3ac0
--- /dev/null
+++ b/chip/stm32/charger_detect.c
@@ -0,0 +1,55 @@
+/* Copyright 2016 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.
+ */
+/* Detect what adapter is connected */
+
+#include "charge_manager.h"
+#include "hooks.h"
+#include "registers.h"
+#include "timer.h"
+
+static void enable_usb(void)
+{
+	/* Enable USB device clock. */
+	STM32_RCC_APB1ENR |= STM32_RCC_PB1_USB;
+}
+DECLARE_HOOK(HOOK_INIT, enable_usb, HOOK_PRIO_DEFAULT);
+
+static void disable_usb(void)
+{
+	/* Disable USB device clock. */
+	STM32_RCC_APB1ENR &= ~STM32_RCC_PB1_USB;
+}
+DECLARE_HOOK(HOOK_SYSJUMP, disable_usb, HOOK_PRIO_DEFAULT);
+
+static uint16_t detect_type(uint16_t det_type)
+{
+	STM32_USB_BCDR &= 0;
+	usleep(1);
+	STM32_USB_BCDR |= (STM32_USB_BCDR_BCDEN | det_type);
+	usleep(1);
+	STM32_USB_BCDR &= ~(STM32_USB_BCDR_BCDEN | det_type);
+	return STM32_USB_BCDR;
+}
+
+
+int charger_detect_get_device_type(void)
+{
+	uint16_t pdet_result;
+
+	if (!(detect_type(STM32_USB_BCDR_DCDEN) & STM32_USB_BCDR_DCDET))
+		return CHARGE_SUPPLIER_PD;
+
+	pdet_result = detect_type(STM32_USB_BCDR_PDEN);
+	/* TODO: add support for detecting proprietary chargers. */
+	if (pdet_result & STM32_USB_BCDR_PDET) {
+		if (detect_type(STM32_USB_BCDR_SDEN) & STM32_USB_BCDR_SDET)
+			return CHARGE_SUPPLIER_BC12_DCP;
+		else
+			return CHARGE_SUPPLIER_BC12_CDP;
+	} else if (pdet_result & STM32_USB_BCDR_PS2DET)
+		return CHARGE_SUPPLIER_PROPRIETARY;
+	else
+		return CHARGE_SUPPLIER_BC12_SDP;
+}
diff --git a/chip/stm32/registers.h b/chip/stm32/registers.h
index 57fb2a9ec0..283fd44498 100644
--- a/chip/stm32/registers.h
+++ b/chip/stm32/registers.h
@@ -1327,6 +1327,15 @@ typedef volatile struct stm32_dma_regs stm32_dma_regs_t;
 #define STM32_USB_LPMCSR           REG16(STM32_USB_FS_BASE + 0x54)
 #define STM32_USB_BCDR             REG16(STM32_USB_FS_BASE + 0x58)
 
+#define STM32_USB_BCDR_BCDEN	    (1 << 0)
+#define STM32_USB_BCDR_DCDEN	    (1 << 1)
+#define STM32_USB_BCDR_PDEN	    (1 << 2)
+#define STM32_USB_BCDR_SDEN	    (1 << 3)
+#define STM32_USB_BCDR_DCDET	    (1 << 4)
+#define STM32_USB_BCDR_PDET	    (1 << 5)
+#define STM32_USB_BCDR_SDET	    (1 << 6)
+#define STM32_USB_BCDR_PS2DET	    (1 << 7)
+
 #define EP_MASK     0x0F0F
 #define EP_TX_DTOG  0x0040
 #define EP_TX_MASK  0x0030
diff --git a/include/charger_detect.h b/include/charger_detect.h
new file mode 100644
index 0000000000..ae2001e418
--- /dev/null
+++ b/include/charger_detect.h
@@ -0,0 +1,17 @@
+/* Copyright 2016 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.
+ */
+/* Detect what adapter is connected */
+
+#ifndef __CROS_CHARGER_DETECT_H
+#define __CROS_CHARGER_DETECT_H
+
+/*
+ * Get attached device type.
+ *
+ * @return CHARGE_SUPPLIER_BC12_* or 0 if the device type was not detected
+ */
+int charger_detect_get_device_type(void);
+
+#endif /* __CROS_CHARGER_DETECT_H */
diff --git a/include/config.h b/include/config.h
index a0a0d5c4cf..1845cd1ff5 100644
--- a/include/config.h
+++ b/include/config.h
@@ -1607,6 +1607,9 @@
 /* Use 32-bit timer for clock source on stm32. */
 #undef CONFIG_STM_HWTIMER32
 
+/* Compile charger detect for STM32 */
+#undef CONFIG_STM32_CHARGER_DETECT
+
 /* Fake hibernate mode */
 #undef CONFIG_STM32L_FAKE_HIBERNATE