usb: typec: handle tcpc vconn oc fault by triggering tcpm error recovery

Add tcpm_port_error_recovery symbol and corresponding event that runs in tcpm_pd_event handler to set the port to the ERROR_RECOVERY state. tcpci drivers can use the symbol to reset the port when tcpc faults affect port functionality.

Signed-off-by RD Babiera <[email protected]>

---
 drivers/usb/typec/tcpm/tcpm.c | 14 ++++++++++++++
 include/linux/usb/tcpm.h      |  1 +
 2 files changed, 15 insertions(+)

drivers/usb/typec/tcpm/tcpm.c +14 -0

index 058d5b853b57..2e553dc63619 100644
@@ -251,6 +251,7 @@ enum frs_typec_current {
 #define TCPM_FRS_EVENT		BIT(3)
 #define TCPM_SOURCING_VBUS	BIT(4)
 #define TCPM_PORT_CLEAN		BIT(5)
+#define TCPM_PORT_ERROR		BIT(6)
 
 #define LOG_BUFFER_ENTRIES	1024
 #define LOG_BUFFER_ENTRY_SIZE	128

@@ -5477,6 +5478,10 @@ static void tcpm_pd_event_handler(struct kthread_work *work)
 					tcpm_set_state(port, tcpm_default_state(port), 0);
 			}
 		}
+		if (events & TCPM_PORT_ERROR) {
+			tcpm_log(port, "port triggering error recovery");
+			tcpm_set_state(port, ERROR_RECOVERY, 0);
+		}
 
 		spin_lock(&port->pd_event_lock);
 	}

@@ -5544,6 +5549,15 @@ bool tcpm_port_is_toggling(struct tcpm_port *port)
 }
 EXPORT_SYMBOL_GPL(tcpm_port_is_toggling);
 
+void tcpm_port_error_recovery(struct tcpm_port *port)
+{
+	spin_lock(&port->pd_event_lock);
+	port->pd_events |= TCPM_PORT_ERROR;
+	spin_unlock(&port->pd_event_lock);
+	kthread_queue_work(port->wq, &port->event_work);
+}
+EXPORT_SYMBOL_GPL(tcpm_port_error_recovery);
+
 static void tcpm_enable_frs_work(struct kthread_work *work)
 {
 	struct tcpm_port *port = container_of(work, struct tcpm_port, enable_frs);

include/linux/usb/tcpm.h +1 -0

index ab7ca872950b..65fac5e1f317 100644
@@ -173,5 +173,6 @@ void tcpm_pd_hard_reset(struct tcpm_port *port);
 void tcpm_tcpc_reset(struct tcpm_port *port);
 void tcpm_port_clean(struct tcpm_port *port);
 bool tcpm_port_is_toggling(struct tcpm_port *port);
+void tcpm_port_error_recovery(struct tcpm_port *port);
 
 #endif /* __LINUX_USB_TCPM_H */

Signature · 1 line

2.43.0.rc1.413.gea7ed67945-goog

Add tcpm_port_error_recovery symbol and corresponding event that runs in tcpm_pd_event handler to set the port to the ERROR_RECOVERY state. tcpci drivers can use the symbol to reset the port when tcpc faults affect port functionality.

Signed-off-by RD Babiera <[email protected]>

Add TCPC_FAULT_STATUS_VCONN_OC constant and corresponding mask definition. Maxim TCPC is capable of detecting VConn over current faults, so add fault to alert mask. When a Vconn over current fault is triggered, put the port in an error recovery state via tcpm_port_error_recovery.

Signed-off-by RD Babiera <[email protected]>

---
 drivers/usb/typec/tcpm/tcpci_maxim_core.c | 20 +++++++++++++++++++-
 include/linux/usb/tcpci.h                 |  5 ++++-
 2 files changed, 23 insertions(+), 2 deletions(-)

drivers/usb/typec/tcpm/tcpci_maxim_core.c +19 -1

index 9454b12a073c..7fb966fd639b 100644
@@ -92,11 +92,16 @@ static void max_tcpci_init_regs(struct max_tcpci_chip *chip)
 		return;
 	}
 
+	/* Vconn Over Current Protection */
+	ret = max_tcpci_write8(chip, TCPC_FAULT_STATUS_MASK, TCPC_FAULT_STATUS_MASK_VCONN_OC);
+	if (ret < 0)
+		return;
+
 	alert_mask = TCPC_ALERT_TX_SUCCESS | TCPC_ALERT_TX_DISCARDED | TCPC_ALERT_TX_FAILED |
 		TCPC_ALERT_RX_HARD_RST | TCPC_ALERT_RX_STATUS | TCPC_ALERT_CC_STATUS |
 		TCPC_ALERT_VBUS_DISCNCT | TCPC_ALERT_RX_BUF_OVF | TCPC_ALERT_POWER_STATUS |
 		/* Enable Extended alert for detecting Fast Role Swap Signal */
-		TCPC_ALERT_EXTND | TCPC_ALERT_EXTENDED_STATUS;
+		TCPC_ALERT_EXTND | TCPC_ALERT_EXTENDED_STATUS | TCPC_ALERT_FAULT;
 
 	ret = max_tcpci_write16(chip, TCPC_ALERT_MASK, alert_mask);
 	if (ret < 0) {

@@ -295,6 +300,19 @@ static irqreturn_t _max_tcpci_irq(struct max_tcpci_chip *chip, u16 status)
 		}
 	}
 
+	if (status & TCPC_ALERT_FAULT) {
+		ret = max_tcpci_read8(chip, TCPC_FAULT_STATUS, &reg_status);
+		if (ret < 0)
+			return ret;
+
+		ret = max_tcpci_write8(chip, TCPC_FAULT_STATUS, reg_status);
+		if (ret < 0)
+			return ret;
+
+		if (reg_status & TCPC_FAULT_STATUS_VCONN_OC)
+			tcpm_port_error_recovery(chip->port);
+	}
+
 	if (status & TCPC_ALERT_EXTND) {
 		ret = max_tcpci_read8(chip, TCPC_ALERT_EXTENDED, &reg_status);
 		if (ret < 0)

include/linux/usb/tcpci.h +4 -1

index 83376473ac76..467e8045e9f8 100644
@@ -36,7 +36,9 @@
 
 #define TCPC_ALERT_MASK			0x12
 #define TCPC_POWER_STATUS_MASK		0x14
-#define TCPC_FAULT_STATUS_MASK		0x15
+
+#define TCPC_FAULT_STATUS_MASK			0x15
+#define TCPC_FAULT_STATUS_MASK_VCONN_OC		BIT(1)
 
 #define TCPC_EXTENDED_STATUS_MASK		0x16
 #define TCPC_EXTENDED_STATUS_MASK_VSAFE0V	BIT(0)

@@ -104,6 +106,7 @@
 
 #define TCPC_FAULT_STATUS		0x1f
 #define TCPC_FAULT_STATUS_ALL_REG_RST_TO_DEFAULT BIT(7)
+#define TCPC_FAULT_STATUS_VCONN_OC	BIT(1)
 
 #define TCPC_ALERT_EXTENDED		0x21
 

Signature · 1 line

2.43.0.rc1.413.gea7ed67945-goog

Add TCPC_FAULT_STATUS_VCONN_OC constant and corresponding mask definition. Maxim TCPC is capable of detecting VConn over current faults, so add fault to alert mask. When a Vconn over current fault is triggered, put the port in an error recovery state via tcpm_port_error_recovery.

Signed-off-by RD Babiera <[email protected]>