Contributors: 14
	  
        
          | Author | 
          Tokens | 
          Token Proportion | 
          Commits | 
          Commit Proportion | 
        
	  
	  
        
        
          | Alessandro Zummo | 
          460 | 
          63.80% | 
          4 | 
          16.67% | 
        
        
          | Alexandre Belloni | 
          162 | 
          22.47% | 
          7 | 
          29.17% | 
        
        
          | Javier Martinez Canillas | 
          34 | 
          4.72% | 
          1 | 
          4.17% | 
        
        
          | Shubhrajyoti Datta | 
          24 | 
          3.33% | 
          1 | 
          4.17% | 
        
        
          | Kumar Gala | 
          13 | 
          1.80% | 
          1 | 
          4.17% | 
        
        
          | Axel Lin | 
          8 | 
          1.11% | 
          2 | 
          8.33% | 
        
        
          | Harvey Harrison | 
          5 | 
          0.69% | 
          1 | 
          4.17% | 
        
        
          | Jingoo Han | 
          4 | 
          0.55% | 
          1 | 
          4.17% | 
        
        
          | Colin Ian King | 
          4 | 
          0.55% | 
          1 | 
          4.17% | 
        
        
          | Paul Gortmaker | 
          3 | 
          0.42% | 
          1 | 
          4.17% | 
        
        
          | Jeff Garzik | 
          1 | 
          0.14% | 
          1 | 
          4.17% | 
        
        
          | David Brownell | 
          1 | 
          0.14% | 
          1 | 
          4.17% | 
        
        
          | Arvind Yadav | 
          1 | 
          0.14% | 
          1 | 
          4.17% | 
        
        
          | Jean Delvare | 
          1 | 
          0.14% | 
          1 | 
          4.17% | 
        
	  
	  
        
          | Total | 
          721 | 
           | 
          24 | 
           | 
	    
	  
    
 
// SPDX-License-Identifier: GPL-2.0
/*
 * An rtc/i2c driver for the Dallas DS1672
 * Copyright 2005-06 Tower Technologies
 *
 * Author: Alessandro Zummo <a.zummo@towertech.it>
 */
#include <linux/i2c.h>
#include <linux/rtc.h>
#include <linux/module.h>
/* Registers */
#define DS1672_REG_CNT_BASE	0
#define DS1672_REG_CONTROL	4
#define DS1672_REG_TRICKLE	5
#define DS1672_REG_CONTROL_EOSC	0x80
/*
 * In the routines that deal directly with the ds1672 hardware, we use
 * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch
 * Time is set to UTC.
 */
static int ds1672_read_time(struct device *dev, struct rtc_time *tm)
{
	struct i2c_client *client = to_i2c_client(dev);
	unsigned long time;
	unsigned char addr = DS1672_REG_CONTROL;
	unsigned char buf[4];
	struct i2c_msg msgs[] = {
		{/* setup read ptr */
			.addr = client->addr,
			.len = 1,
			.buf = &addr
		},
		{/* read date */
			.addr = client->addr,
			.flags = I2C_M_RD,
			.len = 1,
			.buf = buf
		},
	};
	/* read control register */
	if ((i2c_transfer(client->adapter, &msgs[0], 2)) != 2) {
		dev_warn(&client->dev, "Unable to read the control register\n");
		return -EIO;
	}
	if (buf[0] & DS1672_REG_CONTROL_EOSC) {
		dev_warn(&client->dev, "Oscillator not enabled. Set time to enable.\n");
		return -EINVAL;
	}
	addr = DS1672_REG_CNT_BASE;
	msgs[1].len = 4;
	/* read date registers */
	if ((i2c_transfer(client->adapter, &msgs[0], 2)) != 2) {
		dev_err(&client->dev, "%s: read error\n", __func__);
		return -EIO;
	}
	dev_dbg(&client->dev,
		"%s: raw read data - counters=%02x,%02x,%02x,%02x\n",
		__func__, buf[0], buf[1], buf[2], buf[3]);
	time = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
	       (buf[1] << 8) | buf[0];
	rtc_time64_to_tm(time, tm);
	dev_dbg(&client->dev, "%s: tm is %ptR\n", __func__, tm);
	return 0;
}
static int ds1672_set_time(struct device *dev, struct rtc_time *tm)
{
	struct i2c_client *client = to_i2c_client(dev);
	int xfer;
	unsigned char buf[6];
	unsigned long secs = rtc_tm_to_time64(tm);
	buf[0] = DS1672_REG_CNT_BASE;
	buf[1] = secs & 0x000000FF;
	buf[2] = (secs & 0x0000FF00) >> 8;
	buf[3] = (secs & 0x00FF0000) >> 16;
	buf[4] = (secs & 0xFF000000) >> 24;
	buf[5] = 0;		/* set control reg to enable counting */
	xfer = i2c_master_send(client, buf, 6);
	if (xfer != 6) {
		dev_err(&client->dev, "%s: send: %d\n", __func__, xfer);
		return -EIO;
	}
	return 0;
}
static const struct rtc_class_ops ds1672_rtc_ops = {
	.read_time = ds1672_read_time,
	.set_time = ds1672_set_time,
};
static int ds1672_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	int err = 0;
	struct rtc_device *rtc;
	dev_dbg(&client->dev, "%s\n", __func__);
	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
		return -ENODEV;
	rtc = devm_rtc_allocate_device(&client->dev);
	if (IS_ERR(rtc))
		return PTR_ERR(rtc);
	rtc->ops = &ds1672_rtc_ops;
	rtc->range_max = U32_MAX;
	err = rtc_register_device(rtc);
	if (err)
		return err;
	i2c_set_clientdata(client, rtc);
	return 0;
}
static const struct i2c_device_id ds1672_id[] = {
	{ "ds1672", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, ds1672_id);
static const struct of_device_id ds1672_of_match[] = {
	{ .compatible = "dallas,ds1672" },
	{ }
};
MODULE_DEVICE_TABLE(of, ds1672_of_match);
static struct i2c_driver ds1672_driver = {
	.driver = {
		   .name = "rtc-ds1672",
		   .of_match_table = of_match_ptr(ds1672_of_match),
	},
	.probe = &ds1672_probe,
	.id_table = ds1672_id,
};
module_i2c_driver(ds1672_driver);
MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
MODULE_DESCRIPTION("Dallas/Maxim DS1672 timekeeper driver");
MODULE_LICENSE("GPL");