driver/sensor: support access remote sensor by rpmsg

Signed-off-by: Jiuzhu Dong <dongjiuzhu1@xiaomi.com>

drivers/sensors/Kconfig

@@ -18,6 +18,13 @@ config USENSOR
 	---help---
 		Allow application to register user sensor by /dev/usensor.
 
+config SENSORS_RPMSG
+	bool "Sensor rpmsg Support"
+	default n
+	depends on RPTUN
+	---help---
+		Allow application to read or control remote sensor device by rpmsg.
+
 config SENSORS_WTGAHRS2
 	bool "Wtgahrs2 Sensor Support"
 	default n

drivers/sensors/Make.defs

@@ -28,6 +28,10 @@ ifeq ($(CONFIG_USENSOR),y)
 CSRCS += usensor.c
 endif
 
+ifeq ($(CONFIG_SENSORS_RPMSG),y)
+CSRCS += sensor_rpmsg.c
+endif
+
 ifeq ($(CONFIG_SENSORS_WTGAHRS2),y)
   CSRCS += wtgahrs2.c
 endif

drivers/sensors/sensor.c

@@ -599,8 +599,9 @@ static ssize_t sensor_write(FAR struct file *filep, FAR const char *buffer,
 {
   FAR struct inode *inode = filep->f_inode;
   FAR struct sensor_upperhalf_s *upper = inode->i_private;
+  FAR struct sensor_lowerhalf_s *lower = upper->lower;
 
-  return sensor_push_event(upper, buffer, buflen);
+  return lower->push_event(lower->priv, buffer, buflen);
 }
 
 static int sensor_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
@@ -967,8 +968,6 @@ int sensor_custom_register(FAR struct sensor_lowerhalf_s *lower,
 
   /* Initialize the upper-half data structure */
 
-  upper->lower = lower;
-
   list_initialize(&upper->userlist);
   upper->state.esize = esize;
   upper->state.min_interval = ULONG_MAX;
@@ -1007,6 +1006,16 @@ int sensor_custom_register(FAR struct sensor_lowerhalf_s *lower,
       goto drv_err;
     }
 
+#ifdef CONFIG_SENSORS_RPMSG
+  lower = sensor_rpmsg_register(lower, path);
+  if (lower == NULL)
+    {
+      ret = -EIO;
+      goto drv_err;
+    }
+#endif
+
+  upper->lower = lower;
   return ret;
 
 drv_err:
@@ -1069,6 +1078,10 @@ void sensor_custom_unregister(FAR struct sensor_lowerhalf_s *lower,
   sninfo("UnRegistering %s\n", path);
   unregister_driver(path);
 
+#ifdef CONFIG_SENSORS_RPMSG
+  sensor_rpmsg_unregister(lower);
+#endif
+
   nxsem_destroy(&upper->exclsem);
   if (circbuf_is_init(&upper->buffer))
     {

include/nuttx/sensors/sensor.h

@@ -857,6 +857,11 @@ struct sensor_ops_s
  * Sensor driver.
  */
 
+typedef CODE ssize_t (*sensor_push_event_t)(FAR void *priv,
+                                            FAR const void *data,
+                                            size_t bytes);
+typedef CODE void (*sensor_notify_event_t)(FAR void *priv);
+
 struct sensor_lowerhalf_s
 {
   /* The type of sensor device */
@@ -908,8 +913,7 @@ struct sensor_lowerhalf_s
        *   A negated errno value is returned on any failure.
        **********************************************************************/
 
-      CODE ssize_t (*push_event)(FAR void *priv, FAR const void *data,
+      sensor_push_event_t push_event;
-                                 size_t bytes);
 
       /**********************************************************************
        * Name: notify_event
@@ -925,7 +929,7 @@ struct sensor_lowerhalf_s
        *   priv   - Upper half driver handle
        **********************************************************************/
 
-      CODE void (*notify_event)(FAR void *priv);
+      sensor_notify_event_t notify_event;
     };
 
   /* The private opaque pointer to be passed to upper-layer during callback */
@@ -1084,6 +1088,58 @@ void sensor_custom_unregister(FAR struct sensor_lowerhalf_s *dev,
 int usensor_initialize(void);
 #endif
 
+/****************************************************************************
+ * Name: sensor_rpmsg_register
+ *
+ * Description:
+ *   This function registers rpmsg takeover for the real lower half, and
+ *   initialize rpmsg resource.
+ *
+ * Input Parameters:
+ *   lower - The instance of lower half sensor driver.
+ *   path  - The path of character node, ex: /dev/sensor/xxx.
+ *
+ * Returned Value:
+ *   The takeover rpmsg lowerhalf returned on success, NULL on failure.
+ ****************************************************************************/
+
+#ifdef CONFIG_SENSORS_RPMSG
+FAR struct sensor_lowerhalf_s *sensor_rpmsg_register(
+                                       FAR struct sensor_lowerhalf_s *lower,
+                                       FAR const char *path);
+#endif
+
+/****************************************************************************
+ * Name: sensor_rpmsg_unregister
+ *
+ * Description:
+ *   This function unregisters rpmsg takeover for the real lower half, and
+ *   release rpmsg resource. This API corresponds to the
+ *   sensor_rpmsg_register.
+ *
+ * Input Parameters:
+ *   lower - The instance of lower half sensor driver.
+ ****************************************************************************/
+
+#ifdef CONFIG_SENSORS_RPMSG
+void sensor_rpmsg_unregister(FAR struct sensor_lowerhalf_s *lower);
+#endif
+
+/****************************************************************************
+ * Name: sensor_rpmsg_initialize
+ *
+ * Description:
+ *   This function initializes the context of sensor rpmsg, registers
+ *   rpmsg callback and prepares enviroment to intercat with remote sensor.
+ *
+ * Returned Value:
+ *   OK on success; A negated errno value is returned on any failure.
+ ****************************************************************************/
+
+#ifdef CONFIG_SENSORS_RPMSG
+int sensor_rpmsg_initialize(void);
+#endif
+
 #undef EXTERN
 #if defined(__cplusplus)
 }