[adc.c] add finsh voltage conversion command (#5937)

* Update adc.c

add finsh voltage conversion command

components/drivers/include/drivers/adc.h

@@ -7,6 +7,7 @@
  * Date           Author       Notes
  * 2018-05-07     aozima       the first version
  * 2018-11-16     Ernest Chen  add finsh command and update adc function
+ * 2022-05-11      Stanley Lwin add finsh voltage conversion command
  */
 
 #ifndef __ADC_H__
@@ -40,5 +41,6 @@ rt_err_t rt_hw_adc_register(rt_adc_device_t adc,const char *name, const struct r
 rt_uint32_t rt_adc_read(rt_adc_device_t dev, rt_uint32_t channel);
 rt_err_t rt_adc_enable(rt_adc_device_t dev, rt_uint32_t channel);
 rt_err_t rt_adc_disable(rt_adc_device_t dev, rt_uint32_t channel);
+rt_uint32_t rt_adc_voltage(rt_adc_device_t dev, rt_uint32_t channel);
 
 #endif /* __ADC_H__ */

components/drivers/misc/adc.c

@@ -7,6 +7,7 @@
  * Date           Author       Notes
  * 2018-05-07     aozima       the first version
  * 2018-11-16     Ernest Chen  add finsh command and update adc function
+ * 2022-05-11      Stanley Lwin add finsh voltage conversion command
  */
 
 #include <rtthread.h>
@@ -16,6 +17,7 @@
 #include <stdlib.h>
 
 #define DBG_TAG "adc"
+#define REFER_VOLTAGE 330       /*reference voltage, multiplied by 100 and reserve 2 decimal places for data accuracy*/
 #define DBG_LVL DBG_INFO
 #include <rtdbg.h>
 
@@ -152,12 +154,29 @@ rt_err_t rt_adc_disable(rt_adc_device_t dev, rt_uint32_t channel)
     return result;
 }
 
+rt_uint32_t rt_adc_voltage(rt_adc_device_t dev, rt_uint32_t channel)
+{
+   rt_uint32_t value = 0, voltage = 0;
+
+    RT_ASSERT(dev);
+
+    /*read the value and convert to voltage*/
+    if (dev->ops->get_resolution != RT_NULL && dev->ops->convert != RT_NULL)
+    {
+        /*get the convert bits*/
+        rt_uint8_t resolution = dev->ops->get_resolution(dev);
+        dev->ops->convert(dev, channel, &value);
+        voltage = value * REFER_VOLTAGE / (1 << resolution);
+    }
+
+    return voltage;
+}
 #ifdef RT_USING_FINSH
 
 static int adc(int argc, char **argv)
 {
-    int value = 0;
-    int result = RT_EOK;
+    int value = 0, voltage = 0;
+    rt_err_t result = -RT_ERROR;
     static rt_adc_device_t adc_device = RT_NULL;
     char *result_str;
 
@@ -173,14 +192,14 @@ static int adc(int argc, char **argv)
             }
             else
             {
-                rt_kprintf("adc probe <adc_name>   - probe adc by name\n");
+                rt_kprintf("adc probe <device name>   - probe adc by name\n");
             }
         }
         else
         {
             if (adc_device == RT_NULL)
             {
-                rt_kprintf("Please using 'adc probe <adc_name>' first\n");
+                rt_kprintf("Please using 'adc probe <device name>' first\n");
                 return -RT_ERROR;
             }
             if (!strcmp(argv[1], "enable"))
@@ -221,6 +240,19 @@ static int adc(int argc, char **argv)
                     rt_kprintf("adc disable <channel>  - disable adc channel\n");
                 }
             }
+            else if (!strcmp(argv[1], "voltage"))
+            {
+                if(argc == 3)
+                {
+                    voltage = rt_adc_voltage(adc_device, atoi(argv[2]));
+                    result_str = (result == RT_EOK) ? "success" : "failure";
+                    rt_kprintf("%s channel %d voltage is %d.%02d \n", adc_device->parent.parent.name, atoi(argv[2]), voltage / 100, voltage % 100);
+                }
+                else
+                {
+                    rt_kprintf("adc convert voltage <channel> \n");
+                }
+            }
             else
             {
                 rt_kprintf("Unknown command. Please enter 'adc' for help\n");
@@ -230,14 +262,15 @@ static int adc(int argc, char **argv)
     else
     {
         rt_kprintf("Usage: \n");
-        rt_kprintf("adc probe <adc_name>   - probe adc by name\n");
-        rt_kprintf("adc read <channel>     - read adc value on the channel\n");
-        rt_kprintf("adc disable <channel>  - disable adc channel\n");
-        rt_kprintf("adc enable <channel>   - enable adc channel\n");
+        rt_kprintf("adc probe <device name> - probe adc by name\n");
+        rt_kprintf("adc read <channel>      - read adc value on the channel\n");
+        rt_kprintf("adc disable <channel>   - disable adc channel\n");
+        rt_kprintf("adc enable <channel>    - enable adc channel\n");
+
         result = -RT_ERROR;
     }
     return RT_EOK;
 }
-MSH_CMD_EXPORT(adc, adc function);
+MSH_CMD_EXPORT(adc, adc <device name> <option> <channel>);
 
 #endif /* RT_USING_FINSH */