usb: typec: Make bus switch code retimer-aware

Since ports can have retimers associated with them, update the Type-C
alternate mode bus code to also set retimer state when the switch state
is updated.

While we are here, make the typec_retimer_dev_type declaration in the
retimer.h file as extern, so that the header file can be successfully
included in the bus code without redeclaration compilation errors.
Signed-off-by: Prashant Malani <pmalani@chromium.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20230112221609.540754-4-pmalani@chromium.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/typec/bus.c

@@ -11,6 +11,22 @@
 #include "bus.h"
 #include "class.h"
 #include "mux.h"
+#include "retimer.h"
+
+static inline int
+typec_altmode_set_retimer(struct altmode *alt, unsigned long conf, void *data)
+{
+	struct typec_retimer_state state;
+
+	if (!alt->retimer)
+		return 0;
+
+	state.alt = &alt->adev;
+	state.mode = conf;
+	state.data = data;
+
+	return typec_retimer_set(alt->retimer, &state);
+}
 
 static inline int
 typec_altmode_set_mux(struct altmode *alt, unsigned long conf, void *data)
@@ -31,6 +47,12 @@ typec_altmode_set_mux(struct altmode *alt, unsigned long conf, void *data)
 static inline int
 typec_altmode_set_switches(struct altmode *alt, unsigned long conf, void *data)
 {
+	int ret;
+
+	ret = typec_altmode_set_retimer(alt, conf, data);
+	if (ret)
+		return ret;
+
 	return typec_altmode_set_mux(alt, conf, data);
 }
 

drivers/usb/typec/retimer.h

@@ -12,7 +12,7 @@ struct typec_retimer {
 
 #define to_typec_retimer(_dev_) container_of(_dev_, struct typec_retimer, dev)
 
-const struct device_type typec_retimer_dev_type;
+extern const struct device_type typec_retimer_dev_type;
 
 #define is_typec_retimer(dev) ((dev)->type == &typec_retimer_dev_type)