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	We might want to access data stored onto one wire EEPROMs. Create a framework to provide a consistent API. Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com> [eugen.hristev@microchip.com: reworked patch] Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
		
			
				
	
	
		
			117 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			117 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier:	GPL-2.0+
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/*
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 *
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 * Copyright (c) 2015 Free Electrons
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 * Copyright (c) 2015 NextThing Co.
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 * Copyright (c) 2018 Microchip Technology, Inc.
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 *
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 * Maxime Ripard <maxime.ripard@free-electrons.com>
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 * Eugen Hristev <eugen.hristev@microchip.com>
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 *
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 */
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#include <common.h>
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#include <dm.h>
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#include <w1.h>
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#include <w1-eeprom.h>
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#include <dm/device-internal.h>
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int w1_eeprom_read_buf(struct udevice *dev, unsigned int offset,
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		       u8 *buf, unsigned int count)
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{
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	const struct w1_eeprom_ops *ops = device_get_ops(dev);
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	u64 id = 0;
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	int ret;
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	if (!ops->read_buf)
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		return -ENOSYS;
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	ret = w1_eeprom_get_id(dev, &id);
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	if (ret)
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		return ret;
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	if (!id)
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		return -ENODEV;
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	return ops->read_buf(dev, offset, buf, count);
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}
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int w1_eeprom_register_new_device(u64 id)
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{
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	u8 family = id & 0xff;
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	int ret;
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	struct udevice *dev;
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	for (ret = uclass_first_device(UCLASS_W1_EEPROM, &dev);
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	     !ret && dev;
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	     uclass_next_device(&dev)) {
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		if (ret || !dev) {
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			debug("cannot find w1 eeprom dev\n");
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			return ret;
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		}
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		if (dev_get_driver_data(dev) == family) {
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			struct w1_device *w1;
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			w1 = dev_get_parent_platdata(dev);
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			if (w1->id) /* device already in use */
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				continue;
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			w1->id = id;
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			debug("%s: Match found: %s:%s %llx\n", __func__,
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			      dev->name, dev->driver->name, id);
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			return 0;
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		}
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	}
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	debug("%s: No matches found: error %d\n", __func__, ret);
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	return ret;
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}
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int w1_eeprom_get_id(struct udevice *dev, u64 *id)
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{
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	struct w1_device *w1 = dev_get_parent_platdata(dev);
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	if (!w1)
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		return -ENODEV;
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	*id = w1->id;
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	return 0;
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}
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UCLASS_DRIVER(w1_eeprom) = {
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	.name		= "w1_eeprom",
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	.id		= UCLASS_W1_EEPROM,
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	.flags		= DM_UC_FLAG_SEQ_ALIAS,
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#if CONFIG_IS_ENABLED(OF_CONTROL)
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	.post_bind	= dm_scan_fdt_dev,
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#endif
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};
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int w1_eeprom_dm_init(void)
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{
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	struct udevice *dev;
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	struct uclass *uc;
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	int ret;
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	ret = uclass_get(UCLASS_W1_EEPROM, &uc);
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	if (ret) {
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		debug("W1_EEPROM uclass not available\n");
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		return ret;
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	}
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	uclass_foreach_dev(dev, uc) {
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		ret = device_probe(dev);
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		if (ret == -ENODEV) {	/* No such device. */
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			debug("W1_EEPROM not available.\n");
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			continue;
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		}
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		if (ret) {		/* Other error. */
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			printf("W1_EEPROM probe failed, error %d\n", ret);
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			continue;
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		}
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	}
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	return 0;
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}
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