ADD AT91SAM9260 I2C driver

According to the Atmel official recommended, use GPIO instead of TWI for I2C communication

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@2129 bbd45198-f89e-11dd-88c7-29a3b14d5316

bsp/at91sam9260/application.c

@@ -57,6 +57,14 @@
 #include <dfs_romfs.h>
 #endif
 
+#ifdef RT_USING_I2C
+#include <i2c.h>
+
+static struct rt_i2c_hardware_info hw_info[] = {
+	{ RT_I2C_HARDWARE_INFO("pcf8563", 0, 0xA2 >> 1, 0), },
+};
+#endif
+
 void rt_init_thread_entry(void* parameter)
 {
 /* Filesystem Initialization */
@@ -134,6 +142,14 @@ void rt_init_thread_entry(void* parameter)
 	}
 #endif
 
+#ifdef RT_USING_I2C
+	{
+		rt_i2c_core_init();
+		rt_i2c_hw_info_register(hw_info, 1);
+		at91_i2c_init();
+	}
+#endif
+
 }
 
 #ifdef RT_USING_LED

bsp/at91sam9260/at91_i2c_gpio.c

@@ -0,0 +1,125 @@
+/*
+ * File      : at91_i2c_gpio.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2006, 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
+ *
+ * Change Logs:
+ * Date           Author		Notes
+ * 2012-04-25     weety		first version
+ */
+
+#include <rtthread.h>
+#include <rthw.h>
+#include <i2c.h>
+#include <i2c-bit-ops.h>
+#include <at91sam926x.h>
+
+
+static void at91_i2c_gpio_init()
+{
+	at91_sys_write(AT91_PMC_PCER, 1 << AT91SAM9260_ID_PIOA); //enable PIOA clock
+	at91_sys_write(AT91_PIOA + PIO_PUER, (1 << 23));
+	at91_sys_write(AT91_PIOA + PIO_PER, (1 << 23));
+	at91_sys_write(AT91_PIOA + PIO_MDER, (1 << 23));
+	at91_sys_write(AT91_PIOA + PIO_PUER, (1 << 24));
+	at91_sys_write(AT91_PIOA + PIO_PER, (1 << 24));
+	at91_sys_write(AT91_PIOA + PIO_MDER, (1 << 24));
+
+	at91_sys_write(AT91_PIOA + PIO_OER, (1 << 23));
+	at91_sys_write(AT91_PIOA + PIO_OER, (1 << 24));
+
+	at91_sys_write(AT91_PIOA + PIO_SODR, (1 << 23));
+	at91_sys_write(AT91_PIOA + PIO_SODR, (1 << 24));
+}
+
+static void at91_set_sda(void *data, rt_int32_t state)
+{
+	if (state)
+	{
+		at91_sys_write(AT91_PIOA + PIO_SODR, (1 << 23));
+	}
+	else
+	{
+		at91_sys_write(AT91_PIOA + PIO_CODR, (1 << 23));
+	}
+}
+
+static void at91_set_scl(void *data, rt_int32_t state)
+{
+	if (state)
+	{
+		at91_sys_write(AT91_PIOA + PIO_SODR, (1 << 24));
+	}
+	else
+	{
+		at91_sys_write(AT91_PIOA + PIO_CODR, (1 << 24));
+	}
+}
+
+static rt_int32_t  at91_get_sda(void *data)
+{
+	return at91_sys_read(AT91_PIOA + PIO_PDSR) & (1 << 23);
+}
+
+static rt_int32_t  at91_get_scl(void *data)
+{
+	return at91_sys_read(AT91_PIOA + PIO_PDSR) & (1 << 24);
+}
+
+static void at91_udelay (rt_uint32_t us)
+{
+	rt_int32_t i;
+	for (; us > 0; us--)
+	{
+		i = 50000;
+		while(i > 0)
+		{
+			i--;
+		}
+	}
+}
+
+static const struct rt_i2c_bit_ops bit_ops = {
+	RT_NULL,
+	at91_set_sda,
+	at91_set_scl,
+	at91_get_sda,
+	at91_get_scl,
+	
+	at91_udelay,
+
+	5,
+	100
+};
+
+rt_err_t at91_i2c_init(void)
+{
+	struct rt_i2c_bus *bus;
+
+	bus = rt_malloc(sizeof(struct rt_i2c_bus));
+	if (bus == RT_NULL)
+	{
+		rt_kprintf("rt_malloc failed\n");
+		return -RT_ENOMEM;
+	}
+	
+	rt_memset((void *)bus, 0, sizeof(struct rt_i2c_bus));
+	bus->id = 0;
+
+	rt_snprintf(bus->name, sizeof(bus->name), "i2c-gpio%d", bus->id);
+
+	bus->priv = (void *)&bit_ops;
+
+	at91_i2c_gpio_init();
+
+	rt_i2c_bit_add_bus(bus);
+
+	return RT_EOK;
+}
+
+
+