[PATCH] usb: typec: add trace point for typec_set_mode

[Ahmad Fatoum]

Some Type-C controllers toggle muxes themselves. Other controllers like
the TUSB320 report the mode to the host, so it can control the muxes.

To improve debuggability of both kinds of drivers, add a trace point that
can be used to keep track of the mode being set inside the Type-C
framework:

  echo 1 > /sys/kernel/debug/tracing/events/typec/typec_mode/enable

Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>
---
 MAINTAINERS                  |  1 +
 drivers/usb/typec/class.c    |  9 ++++++++-
 include/trace/events/typec.h | 36 ++++++++++++++++++++++++++++++++++++
 3 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/MAINTAINERS b/MAINTAINERS
index c8d4b913f26c..ddd59e5e6eaf 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -27753,6 +27753,7 @@ F:	Documentation/ABI/testing/sysfs-class-typec
 F:	Documentation/driver-api/usb/typec.rst
 F:	drivers/usb/typec/
 F:	include/linux/usb/typec.h
+F:	include/trace/events/typec*.h
 
 USB TYPEC INTEL PMC MUX DRIVER
 M:	Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
index 0977581ad1b6..9316d067f19a 100644
--- a/drivers/usb/typec/class.c
+++ b/drivers/usb/typec/class.c
@@ -20,6 +20,9 @@
 #include "class.h"
 #include "pd.h"
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/typec.h>
+
 static DEFINE_IDA(typec_index_ida);
 
 const struct class typec_class = {
@@ -2427,10 +2430,14 @@ EXPORT_SYMBOL_GPL(typec_get_orientation);
 int typec_set_mode(struct typec_port *port, int mode)
 {
 	struct typec_mux_state state = { };
+	int ret;
 
 	state.mode = mode;
 
-	return typec_mux_set(port->mux, &state);
+	ret = typec_mux_set(port->mux, &state);
+	trace_typec_mode(port, mode, ret);
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(typec_set_mode);
 
diff --git a/include/trace/events/typec.h b/include/trace/events/typec.h
new file mode 100644
index 000000000000..a7dcb9f3fd49
--- /dev/null
+++ b/include/trace/events/typec.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM typec
+
+#if !defined(_TRACE_TYPEC_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_TYPEC_H
+
+#include <linux/usb/typec.h>
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(typec_mode,
+
+	TP_PROTO(struct typec_port *port, int mode, int err),
+
+	TP_ARGS(port, mode, err),
+
+	TP_STRUCT__entry(
+		__string(device, dev_name(&port->dev))
+		__field(int, mode)
+		__field(int, err)
+	),
+
+	TP_fast_assign(
+		__assign_str(device);
+		__entry->mode = mode;
+		__entry->err = err;
+	),
+
+	TP_printk("%s mode=%d (%d)",
+		  __get_str(device), __entry->mode, __entry->err)
+);
+
+#endif /* if !defined(_TRACE_TYPEC_H) || defined(TRACE_HEADER_MULTI_READ) */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>

---
base-commit: 8cd9520d35a6c38db6567e97dd93b1f11f185dc6
change-id: 20260617-typec_set_mode-tracepoint-011fc43feaca

Best regards,
--  
Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>