Put some diagnostics in the tcpm log when there's an over
or under voltage situation.
Signed-off-by: Angus Ainslie (Purism) <angus@xxxxxxxx>
---
drivers/usb/typec/tcpm/tcpci.c | 44 ++++++++++++++++++++++++++++++++++
1 file changed, 44 insertions(+)
diff --git a/drivers/usb/typec/tcpm/tcpci.c b/drivers/usb/typec/tcpm/tcpci.c
index c1f7073a56de..c6e0e48b9a2a 100644
--- a/drivers/usb/typec/tcpm/tcpci.c
+++ b/drivers/usb/typec/tcpm/tcpci.c
@@ -261,6 +261,39 @@ static int tcpci_set_pd_rx(struct tcpc_dev *tcpc, bool enable)
return 0;
}
+static int tcpci_get_vbus_voltage(struct tcpc_dev *tcpc)
+{
+ struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
+ u16 vbus_reg;
+ unsigned int vbus_voltage;
+ int ret, scale;
+
+ ret = tcpci_read16(tcpci, TCPC_VBUS_VOLTAGE, &vbus_reg);
+ if (ret < 0)
+ return ret;
+
+ vbus_voltage = vbus_reg & 0x3f;
+ switch ((ret >> 10) & 3) {
+ case 0:
+ scale = 1;
+ break;
+ case 1:
+ scale = 2;
+ break;
+ case 2:
+ scale = 4;
+ break;
+ case 3:
+ tcpm_log(tcpci->port, "invalid VBUS scale");
+ return -1;
+ }
+
+ if (scale != 1)
+ vbus_voltage *= scale;
+
+ return vbus_voltage;
+}
+
static int tcpci_get_vbus(struct tcpc_dev *tcpc)
{
struct tcpci *tcpci = tcpc_to_tcpci(tcpc);
@@ -463,6 +496,17 @@ irqreturn_t tcpci_irq(struct tcpci *tcpci)
else if (status & TCPC_ALERT_TX_FAILED)
tcpm_pd_transmit_complete(tcpci->port, TCPC_TX_FAILED);
+ if (status & (TCPC_ALERT_V_ALARM_LO | TCPC_ALERT_V_ALARM_HI)) {
+ int ret;
+
+ ret = tcpci_get_vbus_voltage(&tcpci->tcpc);
+
+ if (IS_ERR(ret))
+ tcpm_log(tcpci->port, "Can't read VBUS voltage");
+ else
+ tcpm_log(tcpci->port, "Invalid VBUS voltage %d", ret);
+ }
+
return IRQ_HANDLED;
}
EXPORT_SYMBOL_GPL(tcpci_irq);
--
2.17.1
