[components][drivers] add encoder driven framework

components/drivers/include/drivers/encoder.h

@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2006-2018, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2019-08-08     balanceTWK   the first version
+ */
+
+#ifndef __ENCODER_H__
+#define __ENCODER_H__
+
+#include <rtthread.h>
+#include <rtdevice.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* encoder control command */
+typedef enum
+{
+    ENCODER_INFO_GET = 0x01,        /* get a encoder feature information */
+    ENCODER_SWITCH_ON,              /* switch on encoder */
+    ENCODER_SWITCH_OFF,             /* switch off encoder */
+    ENCODER_COUNT_CLEAR,            /* clear encoder count */
+} rt_encoder_ctrl_t;
+
+/* encoder type */
+typedef enum
+{
+    SINGLE_PHASE_ENCODER = 0x01,    /* single phase encoder */
+    AB_PHASE_ENCODER                /* two phase encoder */
+} rt_encoder_type_t;
+
+struct rt_encoder_device;
+
+struct rt_encoder_ops
+{
+    rt_err_t (*init)(struct rt_encoder_device *encoder);
+    rt_int32_t (*get_count)(struct rt_encoder_device *encoder);
+    rt_err_t (*control)(struct rt_encoder_device *encoder, rt_uint32_t cmd, void *args);
+};
+
+/* Encoder feature information */
+struct rt_encoder_info
+{
+    rt_encoder_type_t type;    /* the type of encoder */
+};
+
+typedef struct rt_encoder_device
+{
+    struct rt_device parent;
+    const struct rt_encoder_ops *ops;
+    const struct rt_encoder_info *info;
+} rt_encoder_t;
+
+rt_err_t rt_device_encoder_register(rt_encoder_t *encoder, const char *name, void *user_data);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __ENCODER_H__ */

components/drivers/include/rtdevice.h

@@ -126,6 +126,10 @@ extern "C" {
 #include "drivers/crypto.h"
 #endif
 
+#ifdef RT_USING_ENCODER
+#include "drivers/encoder.h"
+#endif
+
 #ifdef __cplusplus
 }
 #endif