tcpci: change connect to auto discharge disconnect

It was originally thought the connect/disconnect would be
a good generic way to set/clear auto_discharge_disconnect
but it was not working reliably. Although the points that
we are calling to perform this enable/disable are close to
the connect/disconnect, there is more fine tuning required
to make this work.

BUG=b:144126745,chromium:951683
BRANCH=none
TEST=attach/disconnect charger with and without AP running
TEST=attach/disconnect device with AP running

Change-Id: Ib1418771aec6d0a52895972e4db6881b072c0c3d
Signed-off-by: Denis Brockus <dbrockus@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1960514
Reviewed-by: Edward Hill <ecgh@chromium.org>

5 files changed, 28 insertions, 33 deletions

diff --git a/driver/tcpm/nct38xx.c b/driver/tcpm/nct38xx.c
index b29c270d70..f4b9da3132 100644
--- a/driver/tcpm/nct38xx.c
+++ b/driver/tcpm/nct38xx.c
@@ -305,8 +305,8 @@ const struct tcpm_drv nct38xx_tcpm_drv = {
 #ifdef CONFIG_USB_PD_DISCHARGE_TCPC
 	.tcpc_discharge_vbus	= &tcpci_tcpc_discharge_vbus,
 #endif
-	.tcpc_connect_state_change =
-				  &tcpci_tcpc_connect_state_change,
+	.tcpc_enable_auto_discharge_disconnect =
+				  &tcpci_tcpc_enable_auto_discharge_disconnect,
 #ifdef CONFIG_USB_PD_DUAL_ROLE_AUTO_TOGGLE
 	.drp_toggle		= &tcpci_nct38xx_drp_toggle,
 #endif
diff --git a/driver/tcpm/stub.c b/driver/tcpm/stub.c
index 0ebe8af999..3626f148fc 100644
--- a/driver/tcpm/stub.c
+++ b/driver/tcpm/stub.c
@@ -89,6 +89,10 @@ int tcpm_set_rx_enable(int port, int enable)
 	return tcpc_set_rx_enable(port, enable);
 }
 
+void tcpm_enable_auto_discharge_disconnect(int port, int enable)
+{
+}
+
 int tcpm_has_pending_message(int port)
 {
 	return !rx_buf_is_empty(port);
diff --git a/driver/tcpm/tcpci.c b/driver/tcpm/tcpci.c
index 4194f19e6a..5d16de206a 100644
--- a/driver/tcpm/tcpci.c
+++ b/driver/tcpm/tcpci.c
@@ -10,7 +10,6 @@
 #include "compile_time_macros.h"
 #include "console.h"
 #include "ec_commands.h"
-#include "hooks.h"
 #include "ps8xxx.h"
 #include "task.h"
 #include "tcpci.h"
@@ -283,38 +282,17 @@ void tcpci_tcpc_discharge_vbus(int port, int enable)
 }
 
 /*
- * On a connection state change, it is necessary for TCPCI devices to
- * set the AUTO_DISCHARGE_DISCONNECT bit appropriately.
+ * Auto Discharge Disconnect is supposed to be enabled when we
+ * are connected and disabled after we are disconnected and
+ * VBus is at SafeV0
  */
-void tcpci_tcpc_connect_state_change(int port, int connected)
+void tcpci_tcpc_enable_auto_discharge_disconnect(int port, int enable)
 {
 	tcpc_update8(port,
 		     TCPC_REG_POWER_CTRL,
 		     TCPC_REG_POWER_CTRL_AUTO_DISCHARGE_DISCONNECT,
-		     (connected) ? MASK_SET : MASK_CLR);
-}
-
-static void connect_state_change(int port, int connected)
-{
-	const struct tcpm_drv *tcpc = tcpc_config[port].drv;
-
-	if (tcpc->tcpc_connect_state_change)
-		tcpc->tcpc_connect_state_change(port, connected);
-}
-static void connect_hook(void)
-{
-	int port = TASK_ID_TO_PD_PORT(task_get_current());
-
-	connect_state_change(port, 1);
-}
-DECLARE_HOOK(HOOK_USB_PD_CONNECT, connect_hook, HOOK_PRIO_DEFAULT);
-static void disconnect_hook(void)
-{
-	int port = TASK_ID_TO_PD_PORT(task_get_current());
-
-	connect_state_change(port, 0);
+		     (enable) ? MASK_SET : MASK_CLR);
 }
-DECLARE_HOOK(HOOK_USB_PD_DISCONNECT, disconnect_hook, HOOK_PRIO_DEFAULT);
 
 static int set_role_ctrl(int port, int toggle, int rp, int pull)
 {
@@ -1146,8 +1124,6 @@ const struct tcpm_drv tcpci_tcpm_drv = {
 #ifdef CONFIG_USB_PD_DISCHARGE_TCPC
 	.tcpc_discharge_vbus	= &tcpci_tcpc_discharge_vbus,
 #endif
-	.tcpc_connect_state_change =
-				  &tcpci_tcpc_connect_state_change,
 #ifdef CONFIG_USB_PD_DUAL_ROLE_AUTO_TOGGLE
 	.drp_toggle		= &tcpci_tcpc_drp_toggle,
 #endif
diff --git a/driver/tcpm/tcpci.h b/driver/tcpm/tcpci.h
index 46e1d024aa..566e7905e9 100644
--- a/driver/tcpm/tcpci.h
+++ b/driver/tcpm/tcpci.h
@@ -182,8 +182,7 @@ int tcpci_enter_low_power_mode(int port);
 #ifdef CONFIG_USB_PD_DISCHARGE_TCPC
 void tcpci_tcpc_discharge_vbus(int port, int enable);
 #endif
-
-void tcpci_tcpc_connect_state_change(int port, int connected);
+void tcpci_tcpc_enable_auto_discharge_disconnect(int port, int enable);
 
 int tcpci_tcpm_mux_init(int i2c_addr);
 int tcpci_tcpm_mux_set(int i2c_addr, mux_state_t mux_state);
diff --git a/driver/tcpm/tcpm.h b/driver/tcpm/tcpm.h
index 7669135a31..118275ba3d 100644
--- a/driver/tcpm/tcpm.h
+++ b/driver/tcpm/tcpm.h
@@ -199,6 +199,14 @@ static inline int tcpm_set_rx_enable(int port, int enable)
 	return tcpc_config[port].drv->set_rx_enable(port, enable);
 }
 
+static inline void tcpm_enable_auto_discharge_disconnect(int port, int enable)
+{
+	const struct tcpm_drv *tcpc = tcpc_config[port].drv;
+
+	if (tcpc->tcpc_enable_auto_discharge_disconnect)
+		tcpc->tcpc_enable_auto_discharge_disconnect(port, enable);
+}
+
 /**
  * Reads a message using get_message_raw driver method and puts it into EC's
  * cache.
@@ -374,6 +382,14 @@ int tcpm_set_msg_header(int port, int power_role, int data_role);
 int tcpm_set_rx_enable(int port, int enable);
 
 /**
+ * Enable Auto Discharge Disconnect
+ *
+ * @param port Type-C port number
+ * @param enable true for enable, false for disable
+ */
+void tcpm_enable_auto_discharge_disconnect(int port, int enable);
+
+/**
  * Transmit PD message
  *
  * @param port Type-C port number