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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2008 by Robert Kukla
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "rtc.h"
#include "logf.h"
#include "sw_i2c.h"
#include "i2c-pp.h"
/* The RTC chip is unknown, the information about it was gathered by
* reverse engineering the bootloader.
*/
#define RTC_ADDR 0x60
#define RTC_CMD_CTRL 0 /* OF uses it with single byte 1 or 2 */
#define RTC_CMD_UNKN 1 /* OF uses it with single byte 8 */
#define RTC_CMD_DATA 2
#define RTC_CMD_TEST 7 /* OF uses it with single byte 0xAA */
/* private */
static void reverse_bits(unsigned char* v, int size) {
int i,j,in,out=0;
for(j=0; j<size; j++) {
in = v[j];
out = in;
for(i=0; i<7; i++) {
in = in >>1;
out = out<<1;
out |= (in & 1);
}
v[j] = out;
}
}
static int sw_i2c(int access, int cmd, unsigned char* buf, int count) {
int i, addr;
i2c_lock();
GPIOC_ENABLE |= 0x00000030;
addr = RTC_ADDR | (cmd<<1);
if(access == SW_I2C_READ) {
i = sw_i2c_read(addr, 0, buf, count);
reverse_bits(buf, count);
} else {
reverse_bits(buf, count);
i = sw_i2c_write(addr, 0, buf, count);
}
GPIOC_ENABLE &= ~0x00000030;
i2c_unlock();
return i;
}
/* public */
void rtc_init(void)
{
sw_i2c_init();
#if 0
/* init sequence from OF for reference */
/* currently we rely on the bootloader doing it for us */
bool flag = true;
unsigned char data;
unsigned char v[7] = {0x00,0x47,0x17,0x06,0x03,0x02,0x08}; /* random time */
if(flag) {
GPIOB_ENABLE |= 0x80;
GPIOB_OUTPUT_EN |= 0x80;
GPIOB_OUTPUT_VAL &= ~0x80;
DEV_EN |= 0x1000;
/* some more stuff that is not clear */
sw_i2c(SW_I2C_READ, RTC_CMD_CTRL, &data, 1);
if((data<<0x18)>>0x1e) { /* bit 7 & 6 */
data = 1;
sw_i2c(SW_I2C_WRITE, RTC_CMD_CTRL, &data, 1);
data = 1;
sw_i2c(SW_I2C_WRITE, RTC_CMD_CTRL, &data, 1);
data = 8;
sw_i2c(SW_I2C_WRITE, RTC_CMD_UNKN, &data, 1);
/* more stuff, perhaps set up time array? */
rtc_write_datetime(v);
}
data = 2;
sw_i2c(SW_I2C_WRITE, RTC_CMD_CTRL, &data, 1);
}
data = 2;
sw_i2c(SW_I2C_WRITE, RTC_CMD_CTRL, &data, 1);
#endif
}
int rtc_read_datetime(unsigned char* buf)
{
int i;
unsigned char v[7];
i = sw_i2c(SW_I2C_READ, RTC_CMD_DATA, v, 7);
v[4] &= 0x3f; /* mask out p.m. flag */
for(i=0; i<7; i++)
buf[i] = v[6-i];
return i;
}
int rtc_write_datetime(unsigned char* buf)
{
int i;
unsigned char v[7];
for(i=0; i<7; i++)
v[i]=buf[6-i];
i = sw_i2c(SW_I2C_WRITE, RTC_CMD_DATA, v, 7);
return i;
}
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