thunderbolt: Update tb.h function documentation

Make tb.h function documentation compliant with current kernel-doc
standards. No functional changes.

Signed-off-by: Alan Borzeszkowski <alan.borzeszkowski@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Author: aborzesz

drivers/thunderbolt/tb.h

@@ -558,7 +558,7 @@ static inline void *tb_priv(struct tb *tb)
  * During switch alloc/init tb_upstream_port()->remote may be NULL, even for
  * non root switches (on the NHI port remote is always NULL).
  *
- * Return: Returns the upstream port of the switch.
+ * Return: Pointer to &struct tb_port.
  */
 static inline struct tb_port *tb_upstream_port(struct tb_switch *sw)
 {
@@ -569,8 +569,8 @@ static inline struct tb_port *tb_upstream_port(struct tb_switch *sw)
  * tb_is_upstream_port() - Is the port upstream facing
  * @port: Port to check
  *
- * Returns true if @port is upstream facing port. In case of dual link
- * ports both return true.
+ * Return: %true if @port is upstream facing port. In case of dual link
+ * ports, both return %true.
  */
 static inline bool tb_is_upstream_port(const struct tb_port *port)
 {
@@ -613,7 +613,7 @@ static inline const char *tb_width_name(enum tb_link_width width)
  * tb_port_has_remote() - Does the port have switch connected downstream
  * @port: Port to check
  *
- * Returns true only when the port is primary port and has remote set.
+ * Return: %true only when the port is primary port and has remote set.
  */
 static inline bool tb_port_has_remote(const struct tb_port *port)
 {
@@ -905,8 +905,9 @@ static inline struct tb_switch *tb_switch_parent(struct tb_switch *sw)
  * tb_switch_downstream_port() - Return downstream facing port of parent router
  * @sw: Device router pointer
  *
- * Only call for device routers. Returns the downstream facing port of
- * the parent router.
+ * Call only for device routers.
+ *
+ * Return: Pointer to &struct tb_port or %NULL in case of failure.
  */
 static inline struct tb_port *tb_switch_downstream_port(struct tb_switch *sw)
 {
@@ -918,6 +919,8 @@ static inline struct tb_port *tb_switch_downstream_port(struct tb_switch *sw)
 /**
  * tb_switch_depth() - Returns depth of the connected router
  * @sw: Router
+ *
+ * Return: Router depth level as a number.
  */
 static inline int tb_switch_depth(const struct tb_switch *sw)
 {
@@ -1010,6 +1013,9 @@ static inline bool tb_switch_is_tiger_lake(const struct tb_switch *sw)
  * is handling @sw this function can be called. It is valid to call this
  * after tb_switch_alloc() and tb_switch_configure() has been called
  * (latter only for SW CM case).
+ *
+ * Return: %true if switch is handled by ICM, %false if handled by
+ * software CM.
  */
 static inline bool tb_switch_is_icm(const struct tb_switch *sw)
 {
@@ -1037,6 +1043,8 @@ int tb_switch_tmu_configure(struct tb_switch *sw, enum tb_switch_tmu_mode mode);
  *
  * Checks if given router TMU mode is configured to @mode. Note the
  * router TMU might not be enabled to this mode.
+ *
+ * Return: %true if TMU mode is equal to @mode, %false otherwise.
  */
 static inline bool tb_switch_tmu_is_configured(const struct tb_switch *sw,
 					       enum tb_switch_tmu_mode mode)
@@ -1048,8 +1056,8 @@ static inline bool tb_switch_tmu_is_configured(const struct tb_switch *sw,
  * tb_switch_tmu_is_enabled() - Checks if the specified TMU mode is enabled
  * @sw: Router whose TMU mode to check
  *
- * Return true if hardware TMU configuration matches the requested
- * configuration (and is not %TB_SWITCH_TMU_MODE_OFF).
+ * Return: %true if hardware TMU configuration matches the requested
+ * configuration (and is not %TB_SWITCH_TMU_MODE_OFF), %false otherwise.
  */
 static inline bool tb_switch_tmu_is_enabled(const struct tb_switch *sw)
 {
@@ -1069,9 +1077,10 @@ int tb_switch_clx_disable(struct tb_switch *sw);
  * @clx: The CLx states to check for
  *
  * Checks if the specified CLx is enabled on the router upstream link.
- * Returns true if any of the given states is enabled.
  *
  * Not applicable for a host router.
+ *
+ * Return: %true if any of the given states is enabled, %false otherwise.
  */
 static inline bool tb_switch_clx_is_enabled(const struct tb_switch *sw,
 					    unsigned int clx)
@@ -1103,7 +1112,7 @@ struct tb_port *tb_next_port_on_path(struct tb_port *start, struct tb_port *end,
  * @src: Source adapter
  * @dst: Destination adapter
  *
- * Returns %true only if the specified path from source adapter (@src)
+ * Return: %true only if the specified path from source adapter (@src)
  * to destination adapter (@dst) is directed downstream.
  */
 static inline bool
@@ -1235,7 +1244,7 @@ static inline int tb_route_length(u64 route)
  *
  * Port must not be the upstream port (otherwise a loop is created).
  *
- * Return: Returns a route to the switch behind @port.
+ * Return: Route to the switch behind @port.
  */
 static inline u64 tb_downstream_route(struct tb_port *port)
 {
@@ -1263,7 +1272,7 @@ static inline struct tb_switch *tb_xdomain_parent(struct tb_xdomain *xd)
  * tb_xdomain_downstream_port() - Return downstream facing port of parent router
  * @xd: Xdomain pointer
  *
- * Returns the downstream port the XDomain is connected to.
+ * Return: Pointer to &struct tb_port or %NULL in case of failure.
  */
 static inline struct tb_port *tb_xdomain_downstream_port(struct tb_xdomain *xd)
 {
@@ -1291,7 +1300,7 @@ static inline struct tb_retimer *tb_to_retimer(struct device *dev)
  * usb4_switch_version() - Returns USB4 version of the router
  * @sw: Router to check
  *
- * Returns major version of USB4 router (%1 for v1, %2 for v2 and so
+ * Return: Major version of USB4 router (%1 for v1, %2 for v2 and so
  * on). Can be called to pre-USB4 router too and in that case returns %0.
  */
 static inline unsigned int usb4_switch_version(const struct tb_switch *sw)
@@ -1303,7 +1312,7 @@ static inline unsigned int usb4_switch_version(const struct tb_switch *sw)
  * tb_switch_is_usb4() - Is the switch USB4 compliant
  * @sw: Switch to check
  *
- * Returns true if the @sw is USB4 compliant router, false otherwise.
+ * Return: %true if the @sw is USB4 compliant router, %false otherwise.
  */
 static inline bool tb_switch_is_usb4(const struct tb_switch *sw)
 {