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	Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
		
			
				
	
	
		
			157 lines
		
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			157 lines
		
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0-only
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/*
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 * 1-Wire implementation for the ds2781 chip
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 *
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 * Author: Renata Sayakhova <renata@oktetlabs.ru>
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 *
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 * Based on w1-ds2780 driver
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 */
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/device.h>
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#include <linux/types.h>
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#include <linux/platform_device.h>
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#include <linux/mutex.h>
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#include <linux/w1.h>
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#include "w1_ds2781.h"
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#define W1_FAMILY_DS2781	0x3D
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static int w1_ds2781_do_io(struct device *dev, char *buf, int addr,
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			size_t count, int io)
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{
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	struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
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	if (addr > DS2781_DATA_SIZE || addr < 0)
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		return 0;
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	count = min_t(int, count, DS2781_DATA_SIZE - addr);
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	if (w1_reset_select_slave(sl) == 0) {
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		if (io) {
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			w1_write_8(sl->master, W1_DS2781_WRITE_DATA);
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			w1_write_8(sl->master, addr);
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			w1_write_block(sl->master, buf, count);
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		} else {
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			w1_write_8(sl->master, W1_DS2781_READ_DATA);
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			w1_write_8(sl->master, addr);
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			count = w1_read_block(sl->master, buf, count);
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		}
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	}
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	return count;
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}
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int w1_ds2781_io(struct device *dev, char *buf, int addr, size_t count,
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			int io)
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{
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	struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
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	int ret;
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	if (!dev)
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		return -ENODEV;
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	mutex_lock(&sl->master->bus_mutex);
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	ret = w1_ds2781_do_io(dev, buf, addr, count, io);
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	mutex_unlock(&sl->master->bus_mutex);
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	return ret;
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}
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EXPORT_SYMBOL(w1_ds2781_io);
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int w1_ds2781_eeprom_cmd(struct device *dev, int addr, int cmd)
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{
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	struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
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	if (!dev)
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		return -EINVAL;
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	mutex_lock(&sl->master->bus_mutex);
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	if (w1_reset_select_slave(sl) == 0) {
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		w1_write_8(sl->master, cmd);
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		w1_write_8(sl->master, addr);
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	}
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	mutex_unlock(&sl->master->bus_mutex);
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	return 0;
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}
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EXPORT_SYMBOL(w1_ds2781_eeprom_cmd);
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static ssize_t w1_slave_read(struct file *filp, struct kobject *kobj,
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			     struct bin_attribute *bin_attr, char *buf,
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			     loff_t off, size_t count)
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{
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	struct device *dev = container_of(kobj, struct device, kobj);
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	return w1_ds2781_io(dev, buf, off, count, 0);
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}
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static BIN_ATTR_RO(w1_slave, DS2781_DATA_SIZE);
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static struct bin_attribute *w1_ds2781_bin_attrs[] = {
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	&bin_attr_w1_slave,
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	NULL,
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};
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static const struct attribute_group w1_ds2781_group = {
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	.bin_attrs = w1_ds2781_bin_attrs,
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};
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static const struct attribute_group *w1_ds2781_groups[] = {
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	&w1_ds2781_group,
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	NULL,
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};
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static int w1_ds2781_add_slave(struct w1_slave *sl)
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{
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	int ret;
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	struct platform_device *pdev;
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	pdev = platform_device_alloc("ds2781-battery", PLATFORM_DEVID_AUTO);
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	if (!pdev)
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		return -ENOMEM;
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	pdev->dev.parent = &sl->dev;
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	ret = platform_device_add(pdev);
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	if (ret)
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		goto pdev_add_failed;
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	dev_set_drvdata(&sl->dev, pdev);
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	return 0;
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pdev_add_failed:
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	platform_device_put(pdev);
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	return ret;
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}
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static void w1_ds2781_remove_slave(struct w1_slave *sl)
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{
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	struct platform_device *pdev = dev_get_drvdata(&sl->dev);
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	platform_device_unregister(pdev);
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}
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static struct w1_family_ops w1_ds2781_fops = {
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	.add_slave    = w1_ds2781_add_slave,
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	.remove_slave = w1_ds2781_remove_slave,
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	.groups       = w1_ds2781_groups,
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};
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static struct w1_family w1_ds2781_family = {
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	.fid = W1_FAMILY_DS2781,
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	.fops = &w1_ds2781_fops,
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};
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module_w1_family(w1_ds2781_family);
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MODULE_AUTHOR("Renata Sayakhova <renata@oktetlabs.ru>");
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MODULE_DESCRIPTION("1-wire Driver for Maxim/Dallas DS2781 Stand-Alone Fuel Gauge IC");
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MODULE_LICENSE("GPL");
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MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_DS2781));
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