static int max6902_read_time(struct device *dev, struct rtc_time *dt)
{
int err, century;
struct spi_device *spi = to_spi_device(dev);
unsigned char buf[8];
buf[0] = 0xbf; /* Burst read */
err = spi_write_then_read(spi, buf, 1, buf, 8);
if (err != 0)
return err;
/* The chip sends data in this order:
* Seconds, Minutes, Hours, Date, Month, Day, Year */
dt->tm_sec = bcd2bin(buf[0]);
dt->tm_min = bcd2bin(buf[1]);
dt->tm_hour = bcd2bin(buf[2]);
dt->tm_mday = bcd2bin(buf[3]);
dt->tm_mon = bcd2bin(buf[4]) - 1;
dt->tm_wday = bcd2bin(buf[5]);
dt->tm_year = bcd2bin(buf[6]);
/* Read century */
err = max6902_get_reg(dev, MAX6902_REG_CENTURY, &buf[0]);
if (err != 0)
return err;
century = bcd2bin(buf[0]) * 100;
dt->tm_year += century;
dt->tm_year -= 1900;
return rtc_valid_tm(dt);
}
static int __devinit max6902_probe(struct spi_device *spi)
{
struct rtc_device *rtc;
unsigned char tmp;
struct max6902 *chip;
int res;
rtc = rtc_device_register("max6902",
&spi->dev, &max6902_rtc_ops, THIS_MODULE);
if (IS_ERR(rtc))
return PTR_ERR(rtc);
spi->mode = SPI_MODE_3;
spi->bits_per_word = 8;
spi_setup(spi);
chip = kzalloc(sizeof *chip, GFP_KERNEL);
if (!chip) {
rtc_device_unregister(rtc);
return -ENOMEM;
}
chip->rtc = rtc;
dev_set_drvdata(&spi->dev, chip);
res = max6902_get_reg(&spi->dev, MAX6902_REG_SECONDS, &tmp);
if (res) {
rtc_device_unregister(rtc);
return res;
}
return 0;
}
static int max6902_get_datetime(struct device *dev, struct rtc_time *dt)
{
unsigned char tmp;
int century;
int err;
struct spi_device *spi = to_spi_device(dev);
struct max6902 *chip = dev_get_drvdata(dev);
struct spi_message message;
struct spi_transfer xfer;
int status;
err = max6902_get_reg(dev, MAX6902_REG_CENTURY, &tmp);
if (err)
return err;
/* build the message */
spi_message_init(&message);
memset(&xfer, 0, sizeof(xfer));
xfer.len = 1 + 7; /* Burst read command + 7 registers */
xfer.tx_buf = chip->buf;
xfer.rx_buf = chip->buf;
chip->buf[0] = 0xbf; /* Burst read */
spi_message_add_tail(&xfer, &message);
/* do the i/o */
status = spi_sync(spi, &message);
if (status == 0)
status = message.status;
else
return status;
/* The chip sends data in this order:
* Seconds, Minutes, Hours, Date, Month, Day, Year */
dt->tm_sec = BCD2BIN(chip->buf[1]);
dt->tm_min = BCD2BIN(chip->buf[2]);
dt->tm_hour = BCD2BIN(chip->buf[3]);
dt->tm_mday = BCD2BIN(chip->buf[4]);
dt->tm_mon = BCD2BIN(chip->buf[5]) - 1;
dt->tm_wday = BCD2BIN(chip->buf[6]);
dt->tm_year = BCD2BIN(chip->buf[7]);
century = BCD2BIN(tmp) * 100;
dt->tm_year += century;
dt->tm_year -= 1900;
#ifdef MAX6902_DEBUG
printk("\n%s : Read RTC values\n",__FUNCTION__);
printk("tm_hour: %i\n",dt->tm_hour);
printk("tm_min : %i\n",dt->tm_min);
printk("tm_sec : %i\n",dt->tm_sec);
printk("tm_year: %i\n",dt->tm_year);
printk("tm_mon : %i\n",dt->tm_mon);
printk("tm_mday: %i\n",dt->tm_mday);
printk("tm_wday: %i\n",dt->tm_wday);
#endif
return 0;
}
static int __devinit max6902_probe(struct spi_device *spi)
{
struct rtc_device *rtc;
unsigned char tmp;
int res;
spi->mode = SPI_MODE_3;
spi->bits_per_word = 8;
spi_setup(spi);
res = max6902_get_reg(&spi->dev, MAX6902_REG_SECONDS, &tmp);
if (res != 0)
return res;
rtc = rtc_device_register("max6902",
&spi->dev, &max6902_rtc_ops, THIS_MODULE);
if (IS_ERR(rtc))
return PTR_ERR(rtc);
return 0;
}
