mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-17 23:36:49 +07:00
80ba93639b
The rtc pointer is already checked earlier, it is not necessary to check it again. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lore.kernel.org/r/20190818215232.17320-1-alexandre.belloni@bootlin.com Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
162 lines
3.6 KiB
C
162 lines
3.6 KiB
C
// 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");
|