v4.19.13 snapshot.
diff --git a/drivers/hwtracing/stm/stm.h b/drivers/hwtracing/stm/stm.h
new file mode 100644
index 0000000..923571a
--- /dev/null
+++ b/drivers/hwtracing/stm/stm.h
@@ -0,0 +1,81 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * System Trace Module (STM) infrastructure
+ * Copyright (c) 2014, Intel Corporation.
+ *
+ * STM class implements generic infrastructure for System Trace Module devices
+ * as defined in MIPI STPv2 specification.
+ */
+
+#ifndef _STM_STM_H_
+#define _STM_STM_H_
+
+struct stp_policy;
+struct stp_policy_node;
+
+struct stp_policy_node *
+stp_policy_node_lookup(struct stm_device *stm, char *s);
+void stp_policy_node_put(struct stp_policy_node *policy_node);
+void stp_policy_unbind(struct stp_policy *policy);
+
+void stp_policy_node_get_ranges(struct stp_policy_node *policy_node,
+ unsigned int *mstart, unsigned int *mend,
+ unsigned int *cstart, unsigned int *cend);
+int stp_configfs_init(void);
+void stp_configfs_exit(void);
+
+struct stp_master {
+ unsigned int nr_free;
+ unsigned long chan_map[0];
+};
+
+struct stm_device {
+ struct device dev;
+ struct module *owner;
+ struct stp_policy *policy;
+ struct mutex policy_mutex;
+ int major;
+ unsigned int sw_nmasters;
+ struct stm_data *data;
+ struct mutex link_mutex;
+ spinlock_t link_lock;
+ struct list_head link_list;
+ /* master allocation */
+ spinlock_t mc_lock;
+ struct stp_master *masters[0];
+};
+
+#define to_stm_device(_d) \
+ container_of((_d), struct stm_device, dev)
+
+struct stm_output {
+ spinlock_t lock;
+ unsigned int master;
+ unsigned int channel;
+ unsigned int nr_chans;
+};
+
+struct stm_file {
+ struct stm_device *stm;
+ struct stp_policy_node *policy_node;
+ struct stm_output output;
+};
+
+struct stm_device *stm_find_device(const char *name);
+void stm_put_device(struct stm_device *stm);
+
+struct stm_source_device {
+ struct device dev;
+ struct stm_source_data *data;
+ spinlock_t link_lock;
+ struct stm_device __rcu *link;
+ struct list_head link_entry;
+ /* one output per stm_source device */
+ struct stp_policy_node *policy_node;
+ struct stm_output output;
+};
+
+#define to_stm_source_device(_d) \
+ container_of((_d), struct stm_source_device, dev)
+
+#endif /* _STM_STM_H_ */