linux/drivers/i2c/chips/rtc8564.c

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/*
* linux/drivers/i2c/chips/rtc8564.c
*
* Copyright (C) 2002-2004 Stefan Eletzhofer
*
* based on linux/drivers/acron/char/pcf8583.c
* Copyright (C) 2000 Russell King
*
* 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.
*
* Driver for system3's EPSON RTC 8564 chip
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/bcd.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/rtc.h> /* get the user-level API */
#include <linux/init.h>
#include "rtc8564.h"
#ifdef DEBUG
# define _DBG(x, fmt, args...) do{ if (debug>=x) printk(KERN_DEBUG"%s: " fmt "\n", __FUNCTION__, ##args); } while(0);
#else
# define _DBG(x, fmt, args...) do { } while(0);
#endif
#define _DBGRTCTM(x, rtctm) if (debug>=x) printk("%s: secs=%d, mins=%d, hours=%d, mday=%d, " \
"mon=%d, year=%d, wday=%d VL=%d\n", __FUNCTION__, \
(rtctm).secs, (rtctm).mins, (rtctm).hours, (rtctm).mday, \
(rtctm).mon, (rtctm).year, (rtctm).wday, (rtctm).vl);
struct rtc8564_data {
struct i2c_client client;
u16 ctrl;
};
static inline u8 _rtc8564_ctrl1(struct i2c_client *client)
{
struct rtc8564_data *data = i2c_get_clientdata(client);
return data->ctrl & 0xff;
}
static inline u8 _rtc8564_ctrl2(struct i2c_client *client)
{
struct rtc8564_data *data = i2c_get_clientdata(client);
return (data->ctrl & 0xff00) >> 8;
}
#define CTRL1(c) _rtc8564_ctrl1(c)
#define CTRL2(c) _rtc8564_ctrl2(c)
static int debug;;
module_param(debug, int, S_IRUGO | S_IWUSR);
static struct i2c_driver rtc8564_driver;
static unsigned short ignore[] = { I2C_CLIENT_END };
static unsigned short normal_addr[] = { 0x51, I2C_CLIENT_END };
static struct i2c_client_address_data addr_data = {
.normal_i2c = normal_addr,
.probe = ignore,
.ignore = ignore,
};
static int rtc8564_read_mem(struct i2c_client *client, struct mem *mem);
static int rtc8564_write_mem(struct i2c_client *client, struct mem *mem);
static int rtc8564_read(struct i2c_client *client, unsigned char adr,
unsigned char *buf, unsigned char len)
{
int ret = -EIO;
unsigned char addr[1] = { adr };
struct i2c_msg msgs[2] = {
{client->addr, 0, 1, addr},
{client->addr, I2C_M_RD, len, buf}
};
_DBG(1, "client=%p, adr=%d, buf=%p, len=%d", client, adr, buf, len);
if (!buf) {
ret = -EINVAL;
goto done;
}
ret = i2c_transfer(client->adapter, msgs, 2);
if (ret == 2) {
ret = 0;
}
done:
return ret;
}
static int rtc8564_write(struct i2c_client *client, unsigned char adr,
unsigned char *data, unsigned char len)
{
int ret = 0;
unsigned char _data[16];
struct i2c_msg wr;
int i;
if (!data || len > 15) {
ret = -EINVAL;
goto done;
}
_DBG(1, "client=%p, adr=%d, buf=%p, len=%d", client, adr, data, len);
_data[0] = adr;
for (i = 0; i < len; i++) {
_data[i + 1] = data[i];
_DBG(5, "data[%d] = 0x%02x (%d)", i, data[i], data[i]);
}
wr.addr = client->addr;
wr.flags = 0;
wr.len = len + 1;
wr.buf = _data;
ret = i2c_transfer(client->adapter, &wr, 1);
if (ret == 1) {
ret = 0;
}
done:
return ret;
}
static int rtc8564_attach(struct i2c_adapter *adap, int addr, int kind)
{
int ret;
struct i2c_client *new_client;
struct rtc8564_data *d;
unsigned char data[10];
unsigned char ad[1] = { 0 };
struct i2c_msg ctrl_wr[1] = {
{addr, 0, 2, data}
};
struct i2c_msg ctrl_rd[2] = {
{addr, 0, 1, ad},
{addr, I2C_M_RD, 2, data}
};
d = kzalloc(sizeof(struct rtc8564_data), GFP_KERNEL);
if (!d) {
ret = -ENOMEM;
goto done;
}
new_client = &d->client;
strlcpy(new_client->name, "RTC8564", I2C_NAME_SIZE);
i2c_set_clientdata(new_client, d);
new_client->addr = addr;
new_client->adapter = adap;
new_client->driver = &rtc8564_driver;
_DBG(1, "client=%p", new_client);
/* init ctrl1 reg */
data[0] = 0;
data[1] = 0;
ret = i2c_transfer(new_client->adapter, ctrl_wr, 1);
if (ret != 1) {
printk(KERN_INFO "rtc8564: cant init ctrl1\n");
ret = -ENODEV;
goto done;
}
/* read back ctrl1 and ctrl2 */
ret = i2c_transfer(new_client->adapter, ctrl_rd, 2);
if (ret != 2) {
printk(KERN_INFO "rtc8564: cant read ctrl\n");
ret = -ENODEV;
goto done;
}
d->ctrl = data[0] | (data[1] << 8);
_DBG(1, "RTC8564_REG_CTRL1=%02x, RTC8564_REG_CTRL2=%02x",
data[0], data[1]);
ret = i2c_attach_client(new_client);
done:
if (ret) {
kfree(d);
}
return ret;
}
static int rtc8564_probe(struct i2c_adapter *adap)
{
return i2c_probe(adap, &addr_data, rtc8564_attach);
}
static int rtc8564_detach(struct i2c_client *client)
{
i2c_detach_client(client);
kfree(i2c_get_clientdata(client));
return 0;
}
static int rtc8564_get_datetime(struct i2c_client *client, struct rtc_tm *dt)
{
int ret = -EIO;
unsigned char buf[15];
_DBG(1, "client=%p, dt=%p", client, dt);
if (!dt)
return -EINVAL;
memset(buf, 0, sizeof(buf));
ret = rtc8564_read(client, 0, buf, 15);
if (ret)
return ret;
/* century stored in minute alarm reg */
dt->year = BCD2BIN(buf[RTC8564_REG_YEAR]);
dt->year += 100 * BCD2BIN(buf[RTC8564_REG_AL_MIN] & 0x3f);
dt->mday = BCD2BIN(buf[RTC8564_REG_DAY] & 0x3f);
dt->wday = BCD2BIN(buf[RTC8564_REG_WDAY] & 7);
dt->mon = BCD2BIN(buf[RTC8564_REG_MON_CENT] & 0x1f);
dt->secs = BCD2BIN(buf[RTC8564_REG_SEC] & 0x7f);
dt->vl = (buf[RTC8564_REG_SEC] & 0x80) == 0x80;
dt->mins = BCD2BIN(buf[RTC8564_REG_MIN] & 0x7f);
dt->hours = BCD2BIN(buf[RTC8564_REG_HR] & 0x3f);
_DBGRTCTM(2, *dt);
return 0;
}
static int
rtc8564_set_datetime(struct i2c_client *client, struct rtc_tm *dt, int datetoo)
{
int ret, len = 5;
unsigned char buf[15];
_DBG(1, "client=%p, dt=%p", client, dt);
if (!dt)
return -EINVAL;
_DBGRTCTM(2, *dt);
buf[RTC8564_REG_CTRL1] = CTRL1(client) | RTC8564_CTRL1_STOP;
buf[RTC8564_REG_CTRL2] = CTRL2(client);
buf[RTC8564_REG_SEC] = BIN2BCD(dt->secs);
buf[RTC8564_REG_MIN] = BIN2BCD(dt->mins);
buf[RTC8564_REG_HR] = BIN2BCD(dt->hours);
if (datetoo) {
len += 5;
buf[RTC8564_REG_DAY] = BIN2BCD(dt->mday);
buf[RTC8564_REG_WDAY] = BIN2BCD(dt->wday);
buf[RTC8564_REG_MON_CENT] = BIN2BCD(dt->mon) & 0x1f;
/* century stored in minute alarm reg */
buf[RTC8564_REG_YEAR] = BIN2BCD(dt->year % 100);
buf[RTC8564_REG_AL_MIN] = BIN2BCD(dt->year / 100);
}
ret = rtc8564_write(client, 0, buf, len);
if (ret) {
_DBG(1, "error writing data! %d", ret);
}
buf[RTC8564_REG_CTRL1] = CTRL1(client);
ret = rtc8564_write(client, 0, buf, 1);
if (ret) {
_DBG(1, "error writing data! %d", ret);
}
return ret;
}
static int rtc8564_get_ctrl(struct i2c_client *client, unsigned int *ctrl)
{
struct rtc8564_data *data = i2c_get_clientdata(client);
if (!ctrl)
return -1;
*ctrl = data->ctrl;
return 0;
}
static int rtc8564_set_ctrl(struct i2c_client *client, unsigned int *ctrl)
{
struct rtc8564_data *data = i2c_get_clientdata(client);
unsigned char buf[2];
if (!ctrl)
return -1;
buf[0] = *ctrl & 0xff;
buf[1] = (*ctrl & 0xff00) >> 8;
data->ctrl = *ctrl;
return rtc8564_write(client, 0, buf, 2);
}
static int rtc8564_read_mem(struct i2c_client *client, struct mem *mem)
{
if (!mem)
return -EINVAL;
return rtc8564_read(client, mem->loc, mem->data, mem->nr);
}
static int rtc8564_write_mem(struct i2c_client *client, struct mem *mem)
{
if (!mem)
return -EINVAL;
return rtc8564_write(client, mem->loc, mem->data, mem->nr);
}
static int
rtc8564_command(struct i2c_client *client, unsigned int cmd, void *arg)
{
_DBG(1, "cmd=%d", cmd);
switch (cmd) {
case RTC_GETDATETIME:
return rtc8564_get_datetime(client, arg);
case RTC_SETTIME:
return rtc8564_set_datetime(client, arg, 0);
case RTC_SETDATETIME:
return rtc8564_set_datetime(client, arg, 1);
case RTC_GETCTRL:
return rtc8564_get_ctrl(client, arg);
case RTC_SETCTRL:
return rtc8564_set_ctrl(client, arg);
case MEM_READ:
return rtc8564_read_mem(client, arg);
case MEM_WRITE:
return rtc8564_write_mem(client, arg);
default:
return -EINVAL;
}
}
static struct i2c_driver rtc8564_driver = {
.driver = {
.name = "RTC8564",
},
.id = I2C_DRIVERID_RTC8564,
.attach_adapter = rtc8564_probe,
.detach_client = rtc8564_detach,
.command = rtc8564_command
};
static __init int rtc8564_init(void)
{
return i2c_add_driver(&rtc8564_driver);
}
static __exit void rtc8564_exit(void)
{
i2c_del_driver(&rtc8564_driver);
}
MODULE_AUTHOR("Stefan Eletzhofer <Stefan.Eletzhofer@eletztrick.de>");
MODULE_DESCRIPTION("EPSON RTC8564 Driver");
MODULE_LICENSE("GPL");
module_init(rtc8564_init);
module_exit(rtc8564_exit);