76 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
		
			Executable File
		
	
	
	
	
			
		
		
	
	
			76 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
		
			Executable File
		
	
	
	
	
| /*
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|  * Copyright (c) 2011-2023, Shanghai Real-Thread Electronic Technology Co.,Ltd
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|  *
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|  * Change Logs:
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|  * Date           Author       Notes
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|  * 2020-12-03     quanzhao     the first version
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|  */
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| 
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| #include <time.h>
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| #include <string.h>
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| #include <rtthread.h>
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| 
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| static struct rt_device zero_dev;
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| 
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| static rt_ssize_t zero_read    (rt_device_t dev, rt_off_t pos, void *buffer, rt_size_t size)
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| {
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|     rt_memset(buffer, 0, size);
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|     return size;
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| }
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| 
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| static rt_ssize_t zero_write   (rt_device_t dev, rt_off_t pos, const void *buffer, rt_size_t size)
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| {
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|     return size;
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| }
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| 
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| static rt_err_t  zero_control (rt_device_t dev, int cmd, void *args)
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| {
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|     return RT_EOK;
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| }
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| 
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| #ifdef RT_USING_DEVICE_OPS
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| const static struct rt_device_ops zero_ops =
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| {
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|     RT_NULL,
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|     RT_NULL,
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|     RT_NULL,
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|     zero_read,
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|     zero_write,
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|     zero_control
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| };
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| #endif
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| 
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| int zero_device_init(void)
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| {
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|     static rt_bool_t init_ok = RT_FALSE;
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| 
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|     if (init_ok)
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|     {
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|         return 0;
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|     }
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|     RT_ASSERT(!rt_device_find("zero"));
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|     zero_dev.type    = RT_Device_Class_Miscellaneous;
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| 
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| #ifdef RT_USING_DEVICE_OPS
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|     zero_dev.ops     = &zero_ops;
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| #else
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|     zero_dev.init    = RT_NULL;
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|     zero_dev.open    = RT_NULL;
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|     zero_dev.close   = RT_NULL;
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|     zero_dev.read    = zero_read;
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|     zero_dev.write   = zero_write;
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|     zero_dev.control = zero_control;
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| #endif
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| 
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|     /* no private */
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|     zero_dev.user_data = RT_NULL;
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| 
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|     rt_device_register(&zero_dev, "zero", RT_DEVICE_FLAG_RDWR);
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| 
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|     init_ok = RT_TRUE;
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| 
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|     return 0;
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| }
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| INIT_DEVICE_EXPORT(zero_device_init);
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| 
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