使用lpc408x时，需要用到ADC，因此写了ADC的驱动

bsp/lpc408x/README.md

@@ -51,6 +51,7 @@ finsh />
 | ETH   | 支持     |                |
 | LCD   | 支持     |                |
 | SDRAM | 支持     |                |
+| ADC   | 支持     |                |
 
 ### IO 在板级支持包中的映射情况
 

bsp/lpc408x/drivers/Kconfig

@@ -12,6 +12,11 @@ menu "Hardware Drivers Config"
             select RT_USING_HWTIMER 
             default n
 
+        config BSP_USING_ADC
+            bool "Using ADC"
+            select RT_USING_ADC 
+            default n
+
         menu "UART Drivers"
             config BSP_USING_UART0
                 bool "Enable UART0 P0.2/P0.3(T/R)"

bsp/lpc408x/drivers/SConscript

@@ -23,6 +23,9 @@ if GetDepend(['BSP_USING_SDRAM']):
 if GetDepend('BSP_USING_UART0') or GetDepend('BSP_USING_UART2'):
     src += ['drv_uart.c']
 
+if GetDepend('BSP_USING_ADC'):
+    src += ['drv_adc.c']
+
 group = DefineGroup('Drivers', src, depend = [''], CPPPATH = CPPPATH)
 
 Return('group')

bsp/lpc408x/drivers/drv_adc.c

@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2006-2021, fzxhub
+ */
+
+#include <rtthread.h>
+#include <rtdevice.h>
+#include "board.h"
+#include "drv_adc.h"
+
+#ifdef RT_USING_ADC
+
+#ifdef BSP_USING_ADC
+
+struct lpc_adc
+{
+    LPC_ADC_TypeDef *ADC;
+};
+/*
+* channel:0-7
+*/
+static rt_err_t lpc_adc_enabled(struct rt_adc_device *device, rt_uint32_t channel, rt_bool_t enabled)
+{
+	struct lpc_adc *adc;
+
+    RT_ASSERT(device != RT_NULL);
+    adc = (struct lpc_adc *)device->parent.user_data;
+	
+	//enabled ADC
+	if(enabled == RT_FALSE) adc->ADC->CR &= ~(1<<21);
+	else adc->ADC->CR |= (1<<21);
+	
+	//Select the channel
+	adc->ADC->CR |= (1<<channel);
+
+    return RT_EOK;
+}
+
+static rt_err_t lpc_adc_convert(struct rt_adc_device *device, rt_uint32_t channel, rt_uint32_t *value)
+{
+	rt_uint32_t data;
+
+	struct lpc_adc *adc;
+
+    RT_ASSERT(device != RT_NULL);
+    adc = (struct lpc_adc *)device->parent.user_data;
+	
+	adc->ADC->CR = (LPC_ADC->CR & 0x00FFFF00) | (1<<channel) | (1 << 24);
+	while ((adc->ADC->GDR & 0x80000000) == 0); 
+	adc->ADC->CR = adc->ADC->CR | (1 << 24); 
+	while ((adc->ADC->GDR & 0x80000000) == 0);  
+
+	data = adc->ADC->GDR; 
+	data = (data >> 4) & 0xFFF;
+	
+	*value = data;	
+	
+	return RT_EOK;
+}
+
+static const struct rt_adc_ops lpc_adc_ops =
+{
+	lpc_adc_enabled,
+	lpc_adc_convert,
+};
+
+struct lpc_adc lpc_adc0 =
+{
+    LPC_ADC,
+};
+
+struct rt_adc_device adc0;
+
+int rt_hw_adc_init(void)
+{
+	rt_err_t ret = RT_EOK;
+	struct lpc_adc *adc;
+	
+	adc = &lpc_adc0;
+	
+	adc0.ops = &lpc_adc_ops;
+	adc0.parent.user_data = adc;
+	
+	//ADC port
+	LPC_IOCON->P0_23 = 0x01;     //ADC0[0]
+    LPC_IOCON->P0_24 = 0x01;     //ADC0[1]
+    LPC_IOCON->P0_25 = 0x01;     //ADC0[2]
+    LPC_IOCON->P0_26 = 0x01;     //ADC0[3]
+    LPC_IOCON->P1_30 = 0x03;     //ADC0[4]
+    LPC_IOCON->P1_31 = 0x03;     //ADC0[5]
+    LPC_IOCON->P0_12 = 0x03;     //ADC0[6]
+    LPC_IOCON->P0_13 = 0x03;     //ADC0[7]
+	
+	
+	//clock
+	LPC_SC->PCONP |= (1U << 12);
+	//config
+	LPC_ADC->CR = 0;
+    LPC_ADC->CR = (1 << 0)|      // SEL
+                  ((PeripheralClock / 1000000 - 1) << 8) |    // CLKDIV = Fpclk / 1000000 - 1
+                  (0 << 16)|     // BURST
+                  (0 << 17)|     // CLKS
+                  (1 << 21)|     // PDN
+                  (0 << 22)|     // TEST1
+                  (1 << 24)|     // START
+                  (0 << 27);     // EDGE
+	//waiting
+    while ((LPC_ADC->GDR & 0x80000000) == 0);
+
+	ret = rt_hw_adc_register(&adc0,"adc0",&lpc_adc_ops,adc);
+	
+	return ret;
+}
+
+INIT_BOARD_EXPORT(rt_hw_adc_init);
+#endif /* BSP_USING_ADC */
+
+#endif /* RT_USING_ADC */

bsp/lpc408x/drivers/drv_adc.h

@@ -0,0 +1,10 @@
+/*
+ * Copyright (c) 2006-2021, fzxhub
+ */
+
+#ifndef DRV_ADC_H__
+#define DRV_ADC_H__
+
+int rt_hw_adc_init(void);
+
+#endif