/*
* Read time from chip
*/
int mc146818a_get_time(
int minor,
rtems_time_of_day *time
)
{
uint32_t mc146818a;
getRegister_f getReg;
uint32_t value;
rtems_interrupt_level level;
mc146818a = RTC_Table[ minor ].ulCtrlPort1;
getReg = RTC_Table[ minor ].getRegister;
/*
* No time if power failed
*/
if (((*getReg)( mc146818a, MC146818A_STATUSD ) & MC146818ASD_PWR) == 0)
return -1;
/*
* Wait for time update to complete
*/
rtems_interrupt_disable( level );
while (((*getReg)( mc146818a, MC146818A_STATUSA ) & MC146818ASA_TUP) != 0) {
rtems_interrupt_flash( level );
}
/*
* Read the time (we have at least 244 usec to do this)
*/
value = (*getReg)( mc146818a, MC146818A_YEAR );
value = From_BCD( value );
if ( value < 88 )
time->year = 2000 + value;
else
time->year = 1900 + value;
value = (*getReg)( mc146818a, MC146818A_MONTH );
time->month = From_BCD( value );
value = (*getReg)( mc146818a, MC146818A_DAY );
time->day = From_BCD( value );
value = (*getReg)( mc146818a, MC146818A_HRS );
time->hour = From_BCD( value );
value = (*getReg)( mc146818a, MC146818A_MIN );
time->minute = From_BCD( value );
value = (*getReg)( mc146818a, MC146818A_SEC );
rtems_interrupt_enable( level );
time->second = From_BCD( value );
time->ticks = 0;
return 0;
}
static int m48t08_get_time(
int minor,
rtems_time_of_day *time
)
{
uint32_t m48t08;
getRegister_f getReg;
setRegister_f setReg;
uint8_t controlReg;
uint32_t value1;
uint32_t value2;
m48t08 = RTC_Table[ minor ].ulCtrlPort1;
getReg = RTC_Table[ minor ].getRegister;
setReg = RTC_Table[ minor ].setRegister;
/*
* Put the RTC into read mode
*/
controlReg = (*getReg)( m48t08, M48T08_CONTROL );
(*setReg)( m48t08, M48T08_CONTROL, controlReg | M48T08_CONTROL_READ );
value1 = (*getReg)( m48t08, M48T08_YEAR );
value2 = From_BCD( value1 );
if ( value2 < 88 )
time->year = 2000 + value2;
else
time->year = 1900 + value2;
value1 = (*getReg)( m48t08, M48T08_MONTH );
time->month = From_BCD( value1 );
value1 = (*getReg)( m48t08, M48T08_DATE );
time->day = From_BCD( value1 );
value1 = (*getReg)( m48t08, M48T08_HOUR );
time->hour = From_BCD( value1 );
value1 = (*getReg)( m48t08, M48T08_MINUTE );
time->minute = From_BCD( value1 );
value1 = (*getReg)( m48t08, M48T08_SECOND );
time->second = From_BCD( value1 );
time->ticks = 0;
/*
* Put the RTC back into normal mode.
*/
(*setReg)( m48t08, M48T08_CONTROL, controlReg );
return 0;
}
/* ds1307_initialize --
* Initialize DS1307 real-time clock chip. If RTC is halted, this
* function resume counting.
*
* PARAMETERS:
* minor -- minor RTC device number
*/
void
ds1307_initialize(int minor)
{
i2c_message_status status;
int try;
uint8_t sec;
i2c_bus_number bus;
i2c_address addr;
bus = RTC_Table[minor].ulCtrlPort1;
addr = RTC_Table[minor].ulDataPort;
/* Read SECONDS register */
try = 0;
do {
status = i2c_wbrd(bus, addr, 0, &sec, sizeof(sec));
try++;
} while ((status != I2C_SUCCESSFUL) && (try < 15));
/* If clock is halted, reset and start the clock */
if ((sec & DS1307_SECOND_HALT) != 0)
{
uint8_t start[8];
memset(start, 0, sizeof(start));
start[0] = DS1307_SECOND;
try = 0;
do {
status = i2c_write(bus, addr, start, 2);
} while ((status != I2C_SUCCESSFUL) && (try < 15));
}
}
/* ds1307_get_time --
* read current time from DS1307 real-time clock chip and convert it
* to the rtems_time_of_day structure.
*
* PARAMETERS:
* minor -- minor RTC device number
* time -- place to put return value (date and time)
*
* RETURNS:
* 0, if time obtained successfully
* -1, if error occured
*/
int
ds1307_get_time(int minor, rtems_time_of_day *time)
{
i2c_bus_number bus;
i2c_address addr;
uint8_t info[8];
uint32_t v1, v2;
i2c_message_status status;
int try;
if (time == NULL)
return -1;
bus = RTC_Table[minor].ulCtrlPort1;
addr = RTC_Table[minor].ulDataPort;
memset(time, 0, sizeof(rtems_time_of_day));
try = 0;
do {
status = i2c_wbrd(bus, addr, 0, info, sizeof(info));
try++;
} while ((status != I2C_SUCCESSFUL) && (try < 10));
if (status != I2C_SUCCESSFUL)
{
return -1;
}
v1 = info[DS1307_YEAR];
v2 = From_BCD(v1);
if (v2 < 88)
time->year = 2000 + v2;
else
time->year = 1900 + v2;
v1 = info[DS1307_MONTH] & ~0xE0;
time->month = From_BCD(v1);
v1 = info[DS1307_DAY] & ~0xC0;
time->day = From_BCD(v1);
v1 = info[DS1307_HOUR];
if (v1 & DS1307_HOUR_12)
{
v2 = v1 & ~0xE0;
if (v1 & DS1307_HOUR_PM)
{
time->hour = From_BCD(v2) + 12;
}
else
{
time->hour = From_BCD(v2);
}
}
else
{
v2 = v1 & ~0xC0;
time->hour = From_BCD(v2);
}
v1 = info[DS1307_MINUTE] & ~0x80;
time->minute = From_BCD(v1);
v1 = info[DS1307_SECOND];
v2 = v1 & ~0x80;
time->second = From_BCD(v2);
return 0;
}
/* ds1307_set_time --
* set time to the DS1307 real-time clock chip
*
* PARAMETERS:
* minor -- minor RTC device number
* time -- new date and time to be written to DS1307
*
* RETURNS:
* 0, if time obtained successfully
* -1, if error occured
*/
int
ds1307_set_time(int minor, const rtems_time_of_day *time)
{
i2c_bus_number bus;
i2c_address addr;
uint8_t info[8];
i2c_message_status status;
int try;
if (time == NULL)
return -1;
bus = RTC_Table[minor].ulCtrlPort1;
addr = RTC_Table[minor].ulDataPort;
if (time->year >= 2088)
rtems_fatal_error_occurred(RTEMS_INVALID_NUMBER);
info[0] = DS1307_SECOND;
info[1 + DS1307_YEAR] = To_BCD(time->year % 100);
info[1 + DS1307_MONTH] = To_BCD(time->month);
info[1 + DS1307_DAY] = To_BCD(time->day);
info[1 + DS1307_HOUR] = To_BCD(time->hour);
info[1 + DS1307_MINUTE] = To_BCD(time->minute);
info[1 + DS1307_SECOND] = To_BCD(time->second);
info[1 + DS1307_DAY_OF_WEEK] = 1; /* Do not set day of week */
try = 0;
do {
status = i2c_write(bus, addr, info, 8);
try++;
} while ((status != I2C_SUCCESSFUL) && (try < 10));
if (status != I2C_SUCCESSFUL)
return -1;
else
return 0;
}
/* Driver function table */
rtc_fns ds1307_fns = {
ds1307_initialize,
ds1307_get_time,
ds1307_set_time
};
