343 lines
8.3 KiB
C
343 lines
8.3 KiB
C
/*
|
|
* An I2C driver for the Philips PCF8563 RTC
|
|
* Copyright 2005-06 Tower Technologies
|
|
*
|
|
* Author: Alessandro Zummo <a.zummo@towertech.it>
|
|
* Maintainers: http://www.nslu2-linux.org/
|
|
*
|
|
* based on the other drivers in this same directory.
|
|
*
|
|
* http://www.semiconductors.philips.com/acrobat/datasheets/PCF8563-04.pdf
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#include <linux/i2c.h>
|
|
#include <linux/bcd.h>
|
|
#include <linux/rtc.h>
|
|
|
|
#define DRV_VERSION "0.4.2"
|
|
|
|
/* Addresses to scan: none
|
|
* This chip cannot be reliably autodetected. An empty eeprom
|
|
* located at 0x51 will pass the validation routine due to
|
|
* the way the registers are implemented.
|
|
*/
|
|
static unsigned short normal_i2c[] = { I2C_CLIENT_END };
|
|
|
|
/* Module parameters */
|
|
I2C_CLIENT_INSMOD;
|
|
|
|
#define PCF8563_REG_ST1 0x00 /* status */
|
|
#define PCF8563_REG_ST2 0x01
|
|
|
|
#define PCF8563_REG_SC 0x02 /* datetime */
|
|
#define PCF8563_REG_MN 0x03
|
|
#define PCF8563_REG_HR 0x04
|
|
#define PCF8563_REG_DM 0x05
|
|
#define PCF8563_REG_DW 0x06
|
|
#define PCF8563_REG_MO 0x07
|
|
#define PCF8563_REG_YR 0x08
|
|
|
|
#define PCF8563_REG_AMN 0x09 /* alarm */
|
|
#define PCF8563_REG_AHR 0x0A
|
|
#define PCF8563_REG_ADM 0x0B
|
|
#define PCF8563_REG_ADW 0x0C
|
|
|
|
#define PCF8563_REG_CLKO 0x0D /* clock out */
|
|
#define PCF8563_REG_TMRC 0x0E /* timer control */
|
|
#define PCF8563_REG_TMR 0x0F /* timer */
|
|
|
|
#define PCF8563_SC_LV 0x80 /* low voltage */
|
|
#define PCF8563_MO_C 0x80 /* century */
|
|
|
|
static int pcf8563_probe(struct i2c_adapter *adapter, int address, int kind);
|
|
static int pcf8563_detach(struct i2c_client *client);
|
|
|
|
/*
|
|
* In the routines that deal directly with the pcf8563 hardware, we use
|
|
* rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch.
|
|
*/
|
|
static int pcf8563_get_datetime(struct i2c_client *client, struct rtc_time *tm)
|
|
{
|
|
unsigned char buf[13] = { PCF8563_REG_ST1 };
|
|
|
|
struct i2c_msg msgs[] = {
|
|
{ client->addr, 0, 1, buf }, /* setup read ptr */
|
|
{ client->addr, I2C_M_RD, 13, buf }, /* read status + date */
|
|
};
|
|
|
|
/* read registers */
|
|
if ((i2c_transfer(client->adapter, msgs, 2)) != 2) {
|
|
dev_err(&client->dev, "%s: read error\n", __FUNCTION__);
|
|
return -EIO;
|
|
}
|
|
|
|
if (buf[PCF8563_REG_SC] & PCF8563_SC_LV)
|
|
dev_info(&client->dev,
|
|
"low voltage detected, date/time is not reliable.\n");
|
|
|
|
dev_dbg(&client->dev,
|
|
"%s: raw data is st1=%02x, st2=%02x, sec=%02x, min=%02x, hr=%02x, "
|
|
"mday=%02x, wday=%02x, mon=%02x, year=%02x\n",
|
|
__FUNCTION__,
|
|
buf[0], buf[1], buf[2], buf[3],
|
|
buf[4], buf[5], buf[6], buf[7],
|
|
buf[8]);
|
|
|
|
|
|
tm->tm_sec = BCD2BIN(buf[PCF8563_REG_SC] & 0x7F);
|
|
tm->tm_min = BCD2BIN(buf[PCF8563_REG_MN] & 0x7F);
|
|
tm->tm_hour = BCD2BIN(buf[PCF8563_REG_HR] & 0x3F); /* rtc hr 0-23 */
|
|
tm->tm_mday = BCD2BIN(buf[PCF8563_REG_DM] & 0x3F);
|
|
tm->tm_wday = buf[PCF8563_REG_DW] & 0x07;
|
|
tm->tm_mon = BCD2BIN(buf[PCF8563_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */
|
|
tm->tm_year = BCD2BIN(buf[PCF8563_REG_YR])
|
|
+ (buf[PCF8563_REG_MO] & PCF8563_MO_C ? 100 : 0);
|
|
|
|
dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
|
|
"mday=%d, mon=%d, year=%d, wday=%d\n",
|
|
__FUNCTION__,
|
|
tm->tm_sec, tm->tm_min, tm->tm_hour,
|
|
tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
|
|
|
|
/* the clock can give out invalid datetime, but we cannot return
|
|
* -EINVAL otherwise hwclock will refuse to set the time on bootup.
|
|
*/
|
|
if (rtc_valid_tm(tm) < 0)
|
|
dev_err(&client->dev, "retrieved date/time is not valid.\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int pcf8563_set_datetime(struct i2c_client *client, struct rtc_time *tm)
|
|
{
|
|
int i, err;
|
|
unsigned char buf[9];
|
|
|
|
dev_dbg(&client->dev, "%s: secs=%d, mins=%d, hours=%d, "
|
|
"mday=%d, mon=%d, year=%d, wday=%d\n",
|
|
__FUNCTION__,
|
|
tm->tm_sec, tm->tm_min, tm->tm_hour,
|
|
tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
|
|
|
|
/* hours, minutes and seconds */
|
|
buf[PCF8563_REG_SC] = BIN2BCD(tm->tm_sec);
|
|
buf[PCF8563_REG_MN] = BIN2BCD(tm->tm_min);
|
|
buf[PCF8563_REG_HR] = BIN2BCD(tm->tm_hour);
|
|
|
|
buf[PCF8563_REG_DM] = BIN2BCD(tm->tm_mday);
|
|
|
|
/* month, 1 - 12 */
|
|
buf[PCF8563_REG_MO] = BIN2BCD(tm->tm_mon + 1);
|
|
|
|
/* year and century */
|
|
buf[PCF8563_REG_YR] = BIN2BCD(tm->tm_year % 100);
|
|
if (tm->tm_year / 100)
|
|
buf[PCF8563_REG_MO] |= PCF8563_MO_C;
|
|
|
|
buf[PCF8563_REG_DW] = tm->tm_wday & 0x07;
|
|
|
|
/* write register's data */
|
|
for (i = 0; i < 7; i++) {
|
|
unsigned char data[2] = { PCF8563_REG_SC + i,
|
|
buf[PCF8563_REG_SC + i] };
|
|
|
|
err = i2c_master_send(client, data, sizeof(data));
|
|
if (err != sizeof(data)) {
|
|
dev_err(&client->dev,
|
|
"%s: err=%d addr=%02x, data=%02x\n",
|
|
__FUNCTION__, err, data[0], data[1]);
|
|
return -EIO;
|
|
}
|
|
};
|
|
|
|
return 0;
|
|
}
|
|
|
|
struct pcf8563_limit
|
|
{
|
|
unsigned char reg;
|
|
unsigned char mask;
|
|
unsigned char min;
|
|
unsigned char max;
|
|
};
|
|
|
|
static int pcf8563_validate_client(struct i2c_client *client)
|
|
{
|
|
int i;
|
|
|
|
static const struct pcf8563_limit pattern[] = {
|
|
/* register, mask, min, max */
|
|
{ PCF8563_REG_SC, 0x7F, 0, 59 },
|
|
{ PCF8563_REG_MN, 0x7F, 0, 59 },
|
|
{ PCF8563_REG_HR, 0x3F, 0, 23 },
|
|
{ PCF8563_REG_DM, 0x3F, 0, 31 },
|
|
{ PCF8563_REG_MO, 0x1F, 0, 12 },
|
|
};
|
|
|
|
/* check limits (only registers with bcd values) */
|
|
for (i = 0; i < ARRAY_SIZE(pattern); i++) {
|
|
int xfer;
|
|
unsigned char value;
|
|
unsigned char buf = pattern[i].reg;
|
|
|
|
struct i2c_msg msgs[] = {
|
|
{ client->addr, 0, 1, &buf },
|
|
{ client->addr, I2C_M_RD, 1, &buf },
|
|
};
|
|
|
|
xfer = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
|
|
|
|
if (xfer != ARRAY_SIZE(msgs)) {
|
|
dev_err(&client->adapter->dev,
|
|
"%s: could not read register 0x%02X\n",
|
|
__FUNCTION__, pattern[i].reg);
|
|
|
|
return -EIO;
|
|
}
|
|
|
|
value = BCD2BIN(buf & pattern[i].mask);
|
|
|
|
if (value > pattern[i].max ||
|
|
value < pattern[i].min) {
|
|
dev_dbg(&client->adapter->dev,
|
|
"%s: pattern=%d, reg=%x, mask=0x%02x, min=%d, "
|
|
"max=%d, value=%d, raw=0x%02X\n",
|
|
__FUNCTION__, i, pattern[i].reg, pattern[i].mask,
|
|
pattern[i].min, pattern[i].max,
|
|
value, buf);
|
|
|
|
return -ENODEV;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int pcf8563_rtc_read_time(struct device *dev, struct rtc_time *tm)
|
|
{
|
|
return pcf8563_get_datetime(to_i2c_client(dev), tm);
|
|
}
|
|
|
|
static int pcf8563_rtc_set_time(struct device *dev, struct rtc_time *tm)
|
|
{
|
|
return pcf8563_set_datetime(to_i2c_client(dev), tm);
|
|
}
|
|
|
|
static struct rtc_class_ops pcf8563_rtc_ops = {
|
|
.read_time = pcf8563_rtc_read_time,
|
|
.set_time = pcf8563_rtc_set_time,
|
|
};
|
|
|
|
static int pcf8563_attach(struct i2c_adapter *adapter)
|
|
{
|
|
return i2c_probe(adapter, &addr_data, pcf8563_probe);
|
|
}
|
|
|
|
static struct i2c_driver pcf8563_driver = {
|
|
.driver = {
|
|
.name = "pcf8563",
|
|
},
|
|
.id = I2C_DRIVERID_PCF8563,
|
|
.attach_adapter = &pcf8563_attach,
|
|
.detach_client = &pcf8563_detach,
|
|
};
|
|
|
|
static int pcf8563_probe(struct i2c_adapter *adapter, int address, int kind)
|
|
{
|
|
struct i2c_client *client;
|
|
struct rtc_device *rtc;
|
|
|
|
int err = 0;
|
|
|
|
dev_dbg(&adapter->dev, "%s\n", __FUNCTION__);
|
|
|
|
if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) {
|
|
err = -ENODEV;
|
|
goto exit;
|
|
}
|
|
|
|
if (!(client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL))) {
|
|
err = -ENOMEM;
|
|
goto exit;
|
|
}
|
|
|
|
client->addr = address;
|
|
client->driver = &pcf8563_driver;
|
|
client->adapter = adapter;
|
|
|
|
strlcpy(client->name, pcf8563_driver.driver.name, I2C_NAME_SIZE);
|
|
|
|
/* Verify the chip is really an PCF8563 */
|
|
if (kind < 0) {
|
|
if (pcf8563_validate_client(client) < 0) {
|
|
err = -ENODEV;
|
|
goto exit_kfree;
|
|
}
|
|
}
|
|
|
|
/* Inform the i2c layer */
|
|
if ((err = i2c_attach_client(client)))
|
|
goto exit_kfree;
|
|
|
|
dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n");
|
|
|
|
rtc = rtc_device_register(pcf8563_driver.driver.name, &client->dev,
|
|
&pcf8563_rtc_ops, THIS_MODULE);
|
|
|
|
if (IS_ERR(rtc)) {
|
|
err = PTR_ERR(rtc);
|
|
goto exit_detach;
|
|
}
|
|
|
|
i2c_set_clientdata(client, rtc);
|
|
|
|
return 0;
|
|
|
|
exit_detach:
|
|
i2c_detach_client(client);
|
|
|
|
exit_kfree:
|
|
kfree(client);
|
|
|
|
exit:
|
|
return err;
|
|
}
|
|
|
|
static int pcf8563_detach(struct i2c_client *client)
|
|
{
|
|
int err;
|
|
struct rtc_device *rtc = i2c_get_clientdata(client);
|
|
|
|
if (rtc)
|
|
rtc_device_unregister(rtc);
|
|
|
|
if ((err = i2c_detach_client(client)))
|
|
return err;
|
|
|
|
kfree(client);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __init pcf8563_init(void)
|
|
{
|
|
return i2c_add_driver(&pcf8563_driver);
|
|
}
|
|
|
|
static void __exit pcf8563_exit(void)
|
|
{
|
|
i2c_del_driver(&pcf8563_driver);
|
|
}
|
|
|
|
MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
|
|
MODULE_DESCRIPTION("Philips PCF8563/Epson RTC8564 RTC driver");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_VERSION(DRV_VERSION);
|
|
|
|
module_init(pcf8563_init);
|
|
module_exit(pcf8563_exit);
|