[BSP] Add gpio driver support for beaglebone

bsp/beaglebone/drivers/gpio.c

+/*
+ * File      : gpio.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2015, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ */
+
+
+#include <rthw.h>
+#include <rtthread.h>
+#include <rtdevice.h>
+
+#include <am33xx.h>
+#include "gpio.h"
+
+#ifdef RT_USING_PIN
+
+#define reg(base)         *(int*)(base)
+
+#define GPIO_PIN_LOW              (0x0)
+#define GPIO_PIN_HIGH             (0x1)
+
+#define GPIO_CLEARDATAOUT         (0x190)
+#define GPIO_SETDATAOUT           (0x194)
+#define GPIO_DATAIN               (0x138)
+#define GPIO_OE                   (0x134)
+
+static rt_base_t GPIO_BASE[] =
+{
+    AM33XX_GPIO_0_REGS,
+    AM33XX_GPIO_1_REGS,
+    AM33XX_GPIO_2_REGS,
+    AM33XX_GPIO_3_REGS
+};
+
+static void am33xx_pin_mode(struct rt_device *device, rt_base_t pin, rt_base_t mode)
+{
+    RT_ASSERT(pin >= 0 && pin < 128);
+    RT_ASSERT(mode != PIN_MODE_INPUT_PULLUP); /* Mode not supported */
+    rt_base_t gpiox     = pin >> 5;
+    rt_base_t pinNumber = pin & 0x1F;
+
+    if(PIN_MODE_OUTPUT == mode)
+    {
+        reg(GPIO_BASE[gpiox] + GPIO_OE) &= ~(1 << pinNumber);
+    }
+    else if(PIN_MODE_INPUT == mode)
+    {
+        reg(GPIO_BASE[gpiox] + GPIO_OE) |= (1 << pinNumber);
+    }
+}
+
+static void am33xx_pin_write(struct rt_device *device, rt_base_t pin, rt_base_t value)
+{
+    RT_ASSERT(pin >= 0 && pin < 128);
+    rt_base_t gpiox     = pin >> 5;
+    rt_base_t pinNumber = pin & 0x1F;
+
+    if(GPIO_PIN_HIGH == value)
+    {
+        reg(GPIO_BASE[gpiox] + GPIO_SETDATAOUT) = (1 << pinNumber);
+    }
+    else /* GPIO_PIN_LOW */
+    {
+        reg(GPIO_BASE[gpiox] + GPIO_CLEARDATAOUT) = (1 << pinNumber);
+    }
+}
+
+static int am33xx_pin_read(struct rt_device *device, rt_base_t pin)
+{
+    RT_ASSERT(pin >= 0 && pin < 128);
+    rt_base_t gpiox     = pin >> 5;
+    rt_base_t pinNumber = pin & 0x1F;
+
+    return reg(GPIO_BASE[gpiox] + GPIO_DATAIN) & (1 << pinNumber) ? 1 : 0;
+}
+
+static struct rt_pin_ops am33xx_pin_ops =
+{
+    am33xx_pin_mode,
+    am33xx_pin_write,
+    am33xx_pin_read,
+};
+
+int rt_hw_gpio_init(void)
+{
+    rt_device_pin_register("gpio", &am33xx_pin_ops , RT_NULL);
+    return 0;
+}
+INIT_BOARD_EXPORT(rt_hw_gpio_init);
+#endif

bsp/beaglebone/drivers/gpio.h

+/*
+ * File      : gpio.h
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2015, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ */
+
+#ifndef __GPIO_H__
+#define __GPIO_H__
+
+int rt_hw_gpio_init(void);
+
+#endif

bsp/beaglebone/rtconfig.h

@@ -91,6 +91,8 @@
 #define RT_USING_UART4
 // <bool name="RT_USING_UART5" description="Using uart5" default="true" >
 #define RT_USING_UART5
+// <bool name="RT_USING_PIN" description="Using GPIO Device Driver Framework" default="true" >
+#define RT_USING_PIN
 // <integer name="RT_UART_RX_BUFFER_SIZE" description="The buffer size for UART reception" default="64" />
 #define RT_UART_RX_BUFFER_SIZE    64
 // <bool name=RT_USING_INTERRUPT_INFO description="Using interrupt information description" default="true" />