usb: de-dup common code from old and new PD stack

We still need to pull out more common code between the two stacks, but
this is scaffolding with a few examples.

BRANCH=none
BUG=b:137493121
TEST=unit tests pass

Change-Id: Ibd9dda1e544e06f02aa3dde48ca7de1539700cfa
Signed-off-by: Jett Rink <jettrink@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1744655
Reviewed-by: Denis Brockus <dbrockus@chromium.org>

5 files changed, 101 insertions, 134 deletions

diff --git a/common/build.mk b/common/build.mk
index 63e5d052dc..6b999e1fe9 100644
--- a/common/build.mk
+++ b/common/build.mk
@@ -135,6 +135,7 @@ common-$(CONFIG_USB_I2C)+=usb_i2c.o
 common-$(CONFIG_USB_CHARGER)+=usb_charger.o
 common-$(CONFIG_USB_PORT_POWER_DUMB)+=usb_port_power_dumb.o
 common-$(CONFIG_USB_PORT_POWER_SMART)+=usb_port_power_smart.o
+common-$(CONFIG_USB_POWER_DELIVERY)+=usb_common.o
 ifeq ($(CONFIG_USB_SM_FRAMEWORK),)
 common-$(CONFIG_USB_POWER_DELIVERY)+=usb_pd_protocol.o usb_pd_policy.o
 endif
diff --git a/common/usb_common.c b/common/usb_common.c
new file mode 100644
index 0000000000..86c85898dd
--- /dev/null
+++ b/common/usb_common.c
@@ -0,0 +1,83 @@
+/* Copyright 2019 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.
+ */
+
+/*
+ * Contains common USB functions shared between the old (i.e. usb_pd_protocol)
+ * and the new (i.e. usb_sm_*) USB-C PD stacks.
+ */
+
+#include "common.h"
+#include "charge_state.h"
+#include "usb_pd.h"
+#include "usb_pd_tcpm.h"
+
+int usb_get_battery_soc(void)
+{
+#if defined(CONFIG_CHARGER)
+	return charge_get_percent();
+#elif defined(CONFIG_BATTERY)
+	return board_get_battery_soc();
+#else
+	return 0;
+#endif
+}
+
+/*
+ * CC values for regular sources and Debug sources (aka DTS)
+ *
+ * Source type  Mode of Operation   CC1    CC2
+ * ---------------------------------------------
+ * Regular      Default USB Power   RpUSB  Open
+ * Regular      USB-C @ 1.5 A       Rp1A5  Open
+ * Regular      USB-C @ 3 A	    Rp3A0  Open
+ * DTS		Default USB Power   Rp3A0  Rp1A5
+ * DTS		USB-C @ 1.5 A       Rp1A5  RpUSB
+ * DTS		USB-C @ 3 A	    Rp3A0  RpUSB
+ */
+
+typec_current_t usb_get_typec_current_limit(enum pd_cc_polarity_type polarity,
+	enum tcpc_cc_voltage_status cc1, enum tcpc_cc_voltage_status cc2)
+{
+	typec_current_t charge = 0;
+	enum tcpc_cc_voltage_status cc = polarity ? cc2 : cc1;
+	enum tcpc_cc_voltage_status cc_alt = polarity ? cc1 : cc2;
+
+	switch (cc) {
+	case TYPEC_CC_VOLT_RP_3_0:
+		if (!cc_is_rp(cc_alt) || cc_alt == TYPEC_CC_VOLT_RP_DEF)
+			charge = 3000;
+		else if (cc_alt == TYPEC_CC_VOLT_RP_1_5)
+			charge = 500;
+		break;
+	case TYPEC_CC_VOLT_RP_1_5:
+		charge = 1500;
+		break;
+	case TYPEC_CC_VOLT_RP_DEF:
+		charge = 500;
+		break;
+	default:
+		break;
+	}
+
+	if (IS_ENABLED(CONFIG_USBC_DISABLE_CHARGE_FROM_RP_DEF) && charge == 500)
+		charge = 0;
+
+	if (cc_is_rp(cc_alt))
+		charge |= TYPEC_CURRENT_DTS_MASK;
+
+	return charge;
+}
+
+enum pd_cc_polarity_type get_snk_polarity(enum tcpc_cc_voltage_status cc1,
+	enum tcpc_cc_voltage_status cc2)
+{
+	/* The following assumes:
+	 *
+	 * TYPEC_CC_VOLT_RP_3_0 > TYPEC_CC_VOLT_RP_1_5
+	 * TYPEC_CC_VOLT_RP_1_5 > TYPEC_CC_VOLT_RP_DEF
+	 * TYPEC_CC_VOLT_RP_DEF > TYPEC_CC_VOLT_OPEN
+	 */
+	return cc2 > cc1;
+}
diff --git a/common/usb_pd_protocol.c b/common/usb_pd_protocol.c
index a1d4ccb4c7..be0d43ced2 100644
--- a/common/usb_pd_protocol.c
+++ b/common/usb_pd_protocol.c
@@ -22,6 +22,7 @@
 #include "timer.h"
 #include "util.h"
 #include "usb_charge.h"
+#include "usb_common.h"
 #include "usb_mux.h"
 #include "usb_pd.h"
 #include "usb_pd_tcpm.h"
@@ -2296,23 +2297,12 @@ enum pd_dual_role_states pd_get_dual_role(int port)
 	return drp_state[port];
 }
 
-static inline __maybe_unused int get_battery_soc(void)
-{
-#if defined(CONFIG_CHARGER)
-	return charge_get_percent();
-#elif defined(CONFIG_BATTERY)
-	return board_get_battery_soc();
-#else
-	return 0;
-#endif
-}
-
 #ifdef CONFIG_USB_PD_TRY_SRC
 static void pd_update_try_source(void)
 {
 	int i;
 	int try_src = 0;
-	int batt_soc = get_battery_soc();
+	int batt_soc = usb_get_battery_soc();
 
 	try_src = 0;
 	for (i = 0; i < CONFIG_USB_PD_PORT_COUNT; i++)
@@ -2357,7 +2347,7 @@ static void pd_update_try_source(void)
 static void pd_update_snk_reset(void)
 {
 	int i;
-	int batt_soc = get_battery_soc();
+	int batt_soc = usb_get_battery_soc();
 
 	if (batt_soc < CONFIG_USB_PD_RESET_MIN_BATT_SOC)
 		return;
@@ -2634,58 +2624,7 @@ void pd_ping_enable(int port, int enable)
 		pd[port].flags &= ~PD_FLAGS_PING_ENABLED;
 }
 
-/*
- * CC values for regular sources and Debug sources (aka DTS)
- *
- * Source type  Mode of Operation   CC1    CC2
- * ---------------------------------------------
- * Regular      Default USB Power   RpUSB  Open
- * Regular      USB-C @ 1.5 A       Rp1A5  Open
- * Regular      USB-C @ 3 A         Rp3A0  Open
- * DTS          Default USB Power   Rp3A0  Rp1A5
- * DTS          USB-C @ 1.5 A       Rp1A5  RpUSB
- * DTS          USB-C @ 3 A         Rp3A0  RpUSB
-*/
-
-/**
- * Returns the polarity of a Sink.
- */
-static inline int get_snk_polarity(enum tcpc_cc_voltage_status cc1,
-	enum tcpc_cc_voltage_status cc2)
-{
-	/* the following assumes:
-	 * TYPEC_CC_VOLT_RP_3_0 > TYPEC_CC_VOLT_RP_1_5
-	 * TYPEC_CC_VOLT_RP_1_5 > TYPEC_CC_VOLT_RP_DEF
-	 * TYPEC_CC_VOLT_RP_DEF > TYPEC_CC_VOLT_OPEN
-	 */
-	return (cc2 > cc1);
-}
-
 #if defined(CONFIG_CHARGE_MANAGER)
-/**
- * Returns type C current limit (mA) based upon cc_voltage (mV).
- */
-static typec_current_t get_typec_current_limit(int polarity, int cc1, int cc2)
-{
-	typec_current_t charge;
-	int cc = polarity ? cc2 : cc1;
-	int cc_alt = polarity ? cc1 : cc2;
-
-	if (cc == TYPEC_CC_VOLT_RP_3_0 && cc_alt != TYPEC_CC_VOLT_RP_1_5)
-		charge = 3000;
-	else if (cc == TYPEC_CC_VOLT_RP_1_5)
-		charge = 1500;
-	else if (cc == TYPEC_CC_VOLT_RP_DEF)
-		charge = IS_ENABLED(CONFIG_USBC_DISABLE_CHARGE_FROM_RP_DEF) ?
-				0 : 500;
-	else
-		charge = 0;
-
-	if (cc_is_rp(cc_alt))
-		charge |= TYPEC_CURRENT_DTS_MASK;
-
-	return charge;
-}
 
 /**
  * Signal power request to indicate a charger update that affects the port.
@@ -4004,8 +3943,8 @@ void pd_task(void *u)
 			/* initial data role for sink is UFP */
 			pd_set_data_role(port, PD_ROLE_UFP);
 #if defined(CONFIG_CHARGE_MANAGER)
-			typec_curr = get_typec_current_limit(pd[port].polarity,
-							     cc1, cc2);
+			typec_curr = usb_get_typec_current_limit(
+				pd[port].polarity, cc1, cc2);
 			typec_set_input_current_limit(
 				port, typec_curr, TYPE_C_VOLTAGE);
 #endif
@@ -4105,7 +4044,7 @@ void pd_task(void *u)
 				 * high-power chargers will stay at 15W until a
 				 * reset is sent, depending on boot timing.
 				 */
-				int batt_soc = get_battery_soc();
+				int batt_soc = usb_get_battery_soc();
 
 				if (batt_soc < CONFIG_USB_PD_RESET_MIN_BATT_SOC)
 					pd[port].flags |=
@@ -4176,13 +4115,15 @@ void pd_task(void *u)
 
 			/* Check if CC pull-up has changed */
 			tcpm_get_cc(port, &cc1, &cc2);
-			if (typec_curr != get_typec_current_limit(
+			if (typec_curr != usb_get_typec_current_limit(
 						pd[port].polarity, cc1, cc2)) {
 				/* debounce signal by requiring two reads */
 				if (typec_curr_change) {
 					/* set new input current limit */
-					typec_curr = get_typec_current_limit(
-						pd[port].polarity, cc1, cc2);
+					typec_curr =
+						usb_get_typec_current_limit(
+							pd[port].polarity,
+							cc1, cc2);
 					typec_set_input_current_limit(
 					  port, typec_curr, TYPE_C_VOLTAGE);
 				} else {
diff --git a/common/usbc/usb_tc_drp_acc_trysrc_sm.c b/common/usbc/usb_tc_drp_acc_trysrc_sm.c
index 810fc5476e..4267e8e302 100644
--- a/common/usbc/usb_tc_drp_acc_trysrc_sm.c
+++ b/common/usbc/usb_tc_drp_acc_trysrc_sm.c
@@ -11,6 +11,7 @@
 #include "system.h"
 #include "task.h"
 #include "tcpm.h"
+#include "usb_common.h"
 #include "usb_mux.h"
 #include "usb_pd.h"
 #include "usb_tc_drp_acc_trysrc_sm.h"
@@ -337,11 +338,7 @@ static void pd_update_try_source(void)
 	int i;
 	int try_src = 0;
 
-#ifndef CONFIG_CHARGER
-	int batt_soc = board_get_battery_soc();
-#else
-	int batt_soc = charge_get_percent();
-#endif
+	int batt_soc = usb_get_battery_soc();
 
 	try_src = 0;
 	for (i = 0; i < CONFIG_USB_PD_PORT_COUNT; i++)
@@ -391,37 +388,6 @@ static inline void pd_dev_dump_info(uint16_t dev_id, uint8_t *hash)
 }
 #endif /* CONFIG_CMD_PD_DEV_DUMP_INFO */
 
-#if defined(CONFIG_CHARGE_MANAGER)
-/*
- * TODO(b/137493121): Move this function to a separate file that's shared
- * between the this and the original stack.
- */
-
-/*
- * Returns type C current limit (mA) based upon cc_voltage (mV).
- */
-static typec_current_t get_typec_current_limit(int polarity, int cc1, int cc2)
-{
-	typec_current_t charge;
-	int cc = polarity ? cc2 : cc1;
-	int cc_alt = polarity ? cc1 : cc2;
-
-	if (cc == TYPEC_CC_VOLT_RP_3_0 && cc_alt != TYPEC_CC_VOLT_RP_1_5)
-		charge = 3000;
-	else if (cc == TYPEC_CC_VOLT_RP_1_5)
-		charge = 1500;
-	else if (cc == TYPEC_CC_VOLT_RP_DEF)
-		charge = 500;
-	else
-		charge = 0;
-
-	if (cc_is_rp(cc_alt))
-		charge |= TYPEC_CURRENT_DTS_MASK;
-
-	return charge;
-}
-#endif
-
 static void set_vconn(int port, int enable)
 {
 	if (enable == TC_CHK_FLAG(port, TC_FLAGS_VCONN_ON))
@@ -792,8 +758,8 @@ static void sink_power_sub_states(int port)
 	tc[port].cc_debounce = 0;
 
 	if (IS_ENABLED(CONFIG_CHARGE_MANAGER)) {
-		tc[port].typec_curr =
-			get_typec_current_limit(tc[port].polarity, cc1, cc2);
+		tc[port].typec_curr = usb_get_typec_current_limit(
+			tc[port].polarity, cc1, cc2);
 
 		typec_set_input_current_limit(port,
 			tc[port].typec_curr, TYPE_C_VOLTAGE);
@@ -1074,8 +1040,8 @@ static int tc_attached_snk_entry(int port)
 	tc_set_data_role(port, PD_ROLE_UFP);
 
 	if (IS_ENABLED(CONFIG_CHARGE_MANAGER)) {
-		tc[port].typec_curr =
-			get_typec_current_limit(tc[port].polarity, cc1, cc2);
+		tc[port].typec_curr = usb_get_typec_current_limit(
+			tc[port].polarity, cc1, cc2);
 		typec_set_input_current_limit(port, tc[port].typec_curr,
 						TYPE_C_VOLTAGE);
 		charge_manager_update_dualrole(port, CAP_DEDICATED);
diff --git a/common/usbc/usbc_task.c b/common/usbc/usbc_task.c
index b5b94c126a..c081f7649f 100644
--- a/common/usbc/usbc_task.c
+++ b/common/usbc/usbc_task.c
@@ -116,30 +116,6 @@ enum typec_state_id get_typec_state_id(int port)
 	return tc[port].state_id;
 }
 
-/*
- * CC values for regular sources and Debug sources (aka DTS)
- *
- * Source type  Mode of Operation   CC1    CC2
- * ---------------------------------------------
- * Regular      Default USB Power   RpUSB  Open
- * Regular      USB-C @ 1.5 A       Rp1A5  Open
- * Regular      USB-C @ 3 A         Rp3A0  Open
- * DTS          Default USB Power   Rp3A0  Rp1A5
- * DTS          USB-C @ 1.5 A       Rp1A5  RpUSB
- * DTS          USB-C @ 3 A         Rp3A0  RpUSB
- */
-
-enum pd_cc_polarity_type get_snk_polarity(enum tcpc_cc_voltage_status cc1,
-	enum tcpc_cc_voltage_status cc2)
-{
-	/* the following assumes:
-	 * TYPEC_CC_VOLT_RP_3_0 > TYPEC_CC_VOLT_RP_1_5
-	 * TYPEC_CC_VOLT_RP_1_5 > TYPEC_CC_VOLT_RP_DEF
-	 * TYPEC_CC_VOLT_RP_DEF > TYPEC_CC_VOLT_OPEN
-	 */
-	return (cc2 > cc1) ? POLARITY_CC2 : POLARITY_CC1;
-}
-
 int tc_restart_tcpc(int port)
 {
 	return tcpm_init(port);