[PATCH v2 02/16] rpmsg: add RPMsg control API to register service

[Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>]

Add API to register a RPMsg service to the control device.
The rpmsg_drv_ctrl_info structure links a service to its driver.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
---
 drivers/rpmsg/rpmsg_ctrl.c | 57 ++++++++++++++++++++++++++++++++++++++
 include/linux/rpmsg.h      | 31 +++++++++++++++++++++
 include/uapi/linux/rpmsg.h | 14 ++++++++++
 3 files changed, 102 insertions(+)

diff --git a/drivers/rpmsg/rpmsg_ctrl.c b/drivers/rpmsg/rpmsg_ctrl.c
index 425c3e32ada4..065e2e304019 100644
--- a/drivers/rpmsg/rpmsg_ctrl.c
+++ b/drivers/rpmsg/rpmsg_ctrl.c
@@ -27,6 +27,20 @@ struct rpmsg_ctrl_dev {
 	struct device dev;
 };
 
+/**
+ * struct rpmsg_ctl_info - control info list node
+ * @ctrl:	control driver info
+ * @node:	list node
+ *
+ * This structure is used by rpmsg_ctl to list the registered drivers services
+ */
+struct rpmsg_ctl_info {
+	const struct rpmsg_drv_ctrl_info *ctrl;
+	struct list_head node;
+};
+
+static LIST_HEAD(rpmsg_drv_list);
+
 static DEFINE_IDA(rpmsg_ctrl_ida);
 static DEFINE_IDA(rpmsg_minor_ida);
 
@@ -175,6 +189,49 @@ static struct rpmsg_driver rpmsg_ctrl_driver = {
 	.remove = rpmsg_ctrl_remove,
 };
 
+/**
+ * rpmsg_ctrl_register_ctl() -register control for the associated service
+ * @ctrl: rpmsg driver information
+ *
+ * This function is called by the rpmsg driver to register a service that will
+ * be exposed to be instantiate by the application.
+ */
+int  rpmsg_ctrl_register_ctl(const struct rpmsg_drv_ctrl_info *ctrl)
+{
+	struct rpmsg_ctl_info *drv_info;
+
+	drv_info =  kzalloc(sizeof(*drv_info), GFP_KERNEL);
+	if (!drv_info)
+		return -ENOMEM;
+
+	drv_info->ctrl = ctrl;
+
+	list_add_tail(&drv_info->node, &rpmsg_drv_list);
+
+	return 0;
+}
+EXPORT_SYMBOL(rpmsg_ctrl_register_ctl);
+
+/**
+ * rpmsg_ctrl_unregister_ctl() -unregister control for the associated service
+ * @ctrl: the rpmsg control information
+ *
+ * This function is called by the rpmsg driver to unregister the associated
+ * service.
+ */
+void rpmsg_ctrl_unregister_ctl(const struct rpmsg_drv_ctrl_info *ctrl)
+{
+	struct rpmsg_ctl_info *drv_info, *tmp;
+
+	list_for_each_entry_safe(drv_info, tmp, &rpmsg_drv_list, node) {
+		if (drv_info->ctrl == ctrl) {
+			list_del(&drv_info->node);
+			kfree(drv_info);
+		}
+	}
+}
+EXPORT_SYMBOL(rpmsg_ctrl_unregister_ctl);
+
 static int rpmsg_ctrl_init(void)
 {
 	int ret;
diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
index a5db828b2420..5d64704c2346 100644
--- a/include/linux/rpmsg.h
+++ b/include/linux/rpmsg.h
@@ -26,6 +26,19 @@ struct rpmsg_endpoint;
 struct rpmsg_device_ops;
 struct rpmsg_endpoint_ops;
 
+/**
+ * struct rpmsg_drv_ctrl_info - rpmsg ctrl structure
+ * @drv_name:	name of the associated driver
+ * @service:	the associated rpmsg service listed in @rpmsg_services
+ *
+ * This structure is used by rpmsg_ctl to link the endpoint creation to the
+ * service rpmsg driver.
+ */
+struct rpmsg_drv_ctrl_info {
+	const char *drv_name;
+	u32  service;
+};
+
 /**
  * struct rpmsg_channel_info - channel info representation
  * @name: name of service
@@ -315,4 +328,22 @@ static inline __poll_t rpmsg_poll(struct rpmsg_endpoint *ept,
 	module_driver(__rpmsg_driver, register_rpmsg_driver, \
 			unregister_rpmsg_driver)
 
+#if IS_ENABLED(CONFIG_RPMSG_CTRL)
+
+int  rpmsg_ctrl_register_ctl(const struct rpmsg_drv_ctrl_info *ctrl);
+void rpmsg_ctrl_unregister_ctl(const struct rpmsg_drv_ctrl_info *ctrl);
+
+#else
+
+static inline int rpmsg_ctrl_register_ctl(const struct rpmsg_drv_ctrl_info *ctrl)
+{
+	return 0;
+}
+
+static inline void rpmsg_ctrl_unregister_ctl(const struct rpmsg_drv_ctrl_info *ctrl)
+{
+}
+
+#endif /* IS_ENABLED(CONFIG_RPMSG_CTRL) */
+
 #endif /* _LINUX_RPMSG_H */
diff --git a/include/uapi/linux/rpmsg.h b/include/uapi/linux/rpmsg.h
index e14c6dab4223..0b0cb028e0b3 100644
--- a/include/uapi/linux/rpmsg.h
+++ b/include/uapi/linux/rpmsg.h
@@ -9,6 +9,20 @@
 #include <linux/ioctl.h>
 #include <linux/types.h>
 
+/**
+ * enum rpmsg_services - list of supported RPMsg services
+ *
+ * @RPMSG_RAW_SERVICE: char device RPMSG service
+ * @RPMSG_START_PRIVATE_SERVICES: private services have to be declared after.
+ */
+enum rpmsg_services {
+	/* Reserved services */
+	RPMSG_RAW_SERVICE =  0,
+
+	/* Private services */
+	RPMSG_START_PRIVATE_SERVICES =  1024,
+};
+
 /**
  * struct rpmsg_endpoint_info - endpoint info representation
  * @name: name of service
-- 
2.17.1