89 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			89 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * OF helpers for the I2C API
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 *
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 * Copyright (c) 2008 Jochen Friedrich <jochen@scram.de>
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 *
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 * Based on a previous patch from Jon Smirl <jonsmirl@gmail.com>
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 *
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 * This program is free software; you can redistribute it and/or modify
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 * it under the terms of the GNU General Public License as published by
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 * the Free Software Foundation; either version 2 of the License, or
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 * (at your option) any later version.
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 */
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#include <linux/i2c.h>
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#include <linux/of.h>
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#include <linux/of_i2c.h>
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#include <linux/module.h>
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void of_register_i2c_devices(struct i2c_adapter *adap,
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			     struct device_node *adap_node)
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{
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	void *result;
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	struct device_node *node;
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	for_each_child_of_node(adap_node, node) {
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		struct i2c_board_info info = {};
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		struct dev_archdata dev_ad = {};
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		const u32 *addr;
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		int len;
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		if (of_modalias_node(node, info.type, sizeof(info.type)) < 0)
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			continue;
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		addr = of_get_property(node, "reg", &len);
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		if (!addr || len < sizeof(int) || *addr > (1 << 10) - 1) {
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			printk(KERN_ERR
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			       "of-i2c: invalid i2c device entry\n");
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			continue;
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		}
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		info.irq = irq_of_parse_and_map(node, 0);
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		info.addr = *addr;
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		dev_archdata_set_node(&dev_ad, node);
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		info.archdata = &dev_ad;
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		request_module("%s", info.type);
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		result = i2c_new_device(adap, &info);
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		if (result == NULL) {
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			printk(KERN_ERR
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			       "of-i2c: Failed to load driver for %s\n",
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			       info.type);
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			irq_dispose_mapping(info.irq);
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			continue;
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		}
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		/*
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		 * Get the node to not lose the dev_archdata->of_node.
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		 * Currently there is no way to put it back, as well as no
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		 * of_unregister_i2c_devices() call.
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		 */
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		of_node_get(node);
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	}
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}
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EXPORT_SYMBOL(of_register_i2c_devices);
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static int of_dev_node_match(struct device *dev, void *data)
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{
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        return dev_archdata_get_node(&dev->archdata) == data;
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}
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/* must call put_device() when done with returned i2c_client device */
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struct i2c_client *of_find_i2c_device_by_node(struct device_node *node)
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{
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	struct device *dev;
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	dev = bus_find_device(&i2c_bus_type, NULL, node,
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					 of_dev_node_match);
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	if (!dev)
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		return NULL;
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	return to_i2c_client(dev);
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}
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EXPORT_SYMBOL(of_find_i2c_device_by_node);
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MODULE_LICENSE("GPL");
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