diff options
Diffstat (limited to 'drivers/rtc/ds1306.c')
| -rw-r--r-- | drivers/rtc/ds1306.c | 67 |
1 files changed, 50 insertions, 17 deletions
diff --git a/drivers/rtc/ds1306.c b/drivers/rtc/ds1306.c index 1c8ac7f292..29854fc7c4 100644 --- a/drivers/rtc/ds1306.c +++ b/drivers/rtc/ds1306.c @@ -62,13 +62,6 @@ #define RTC_USER_RAM_BASE 0x20 -/* - * External table of chip select functions (see the appropriate board - * support for the actual definition of the table). - */ -extern spi_chipsel_type spi_chipsel[]; -extern int spi_chipsel_cnt; - static unsigned int bin2bcd (unsigned int n); static unsigned char bcd2bin (unsigned char c); @@ -305,11 +298,29 @@ void rtc_reset (void) static unsigned char rtc_read (unsigned char reg); static void rtc_write (unsigned char reg, unsigned char val); +static struct spi_slave *slave; + /* read clock time from DS1306 and return it in *tmp */ int rtc_get (struct rtc_time *tmp) { unsigned char sec, min, hour, mday, wday, mon, year; + /* + * Assuming Vcc = 2.0V (lowest speed) + * + * REVISIT: If we add an rtc_init() function we can do this + * step just once. + */ + if (!slave) { + slave = spi_setup_slave(0, CFG_SPI_RTC_DEVID, 600000, + SPI_MODE_3 | SPI_CS_HIGH); + if (!slave) + return; + } + + if (spi_claim_bus(slave)) + return; + sec = rtc_read (RTC_SECONDS); min = rtc_read (RTC_MINUTES); hour = rtc_read (RTC_HOURS); @@ -318,6 +329,8 @@ int rtc_get (struct rtc_time *tmp) mon = rtc_read (RTC_MONTH); year = rtc_read (RTC_YEAR); + spi_release_bus(slave); + debug ("Get RTC year: %02x mon: %02x mday: %02x wday: %02x " "hr: %02x min: %02x sec: %02x\n", year, mon, mday, wday, hour, min, sec); @@ -360,6 +373,17 @@ int rtc_get (struct rtc_time *tmp) /* set clock time from *tmp in DS1306 RTC */ void rtc_set (struct rtc_time *tmp) { + /* Assuming Vcc = 2.0V (lowest speed) */ + if (!slave) { + slave = spi_setup_slave(0, CFG_SPI_RTC_DEVID, 600000, + SPI_MODE_3 | SPI_CS_HIGH); + if (!slave) + return; + } + + if (spi_claim_bus(slave)) + return; + debug ("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, tmp->tm_hour, tmp->tm_min, tmp->tm_sec); @@ -371,6 +395,8 @@ void rtc_set (struct rtc_time *tmp) rtc_write (RTC_DATE_OF_MONTH, bin2bcd (tmp->tm_mday)); rtc_write (RTC_MONTH, bin2bcd (tmp->tm_mon)); rtc_write (RTC_YEAR, bin2bcd (tmp->tm_year - 2000)); + + spi_release_bus(slave); } /* ------------------------------------------------------------------------- */ @@ -378,6 +404,17 @@ void rtc_set (struct rtc_time *tmp) /* reset the DS1306 */ void rtc_reset (void) { + /* Assuming Vcc = 2.0V (lowest speed) */ + if (!slave) { + slave = spi_setup_slave(0, CFG_SPI_RTC_DEVID, 600000, + SPI_MODE_3 | SPI_CS_HIGH); + if (!slave) + return; + } + + if (spi_claim_bus(slave)) + return; + /* clear the control register */ rtc_write (RTC_CONTROL, 0x00); /* 1st step: reset WP */ rtc_write (RTC_CONTROL, 0x00); /* 2nd step: reset 1Hz, AIE1, AIE0 */ @@ -391,22 +428,18 @@ void rtc_reset (void) rtc_write (RTC_HOURS_ALARM1, 0x00); rtc_write (RTC_DAY_OF_WEEK_ALARM0, 0x00); rtc_write (RTC_DAY_OF_WEEK_ALARM1, 0x00); + + spi_release_bus(slave); } /* ------------------------------------------------------------------------- */ static unsigned char rtc_read (unsigned char reg) { - unsigned char dout[2]; /* SPI Output Data Bytes */ - unsigned char din[2]; /* SPI Input Data Bytes */ - - dout[0] = reg; + int ret; - if (spi_xfer (spi_chipsel[CFG_SPI_RTC_DEVID], 16, dout, din) != 0) { - return 0; - } else { - return din[1]; - } + ret = spi_w8r8(slave, reg); + return ret < 0 ? 0 : ret; } /* ------------------------------------------------------------------------- */ @@ -419,7 +452,7 @@ static void rtc_write (unsigned char reg, unsigned char val) dout[0] = 0x80 | reg; dout[1] = val; - spi_xfer (spi_chipsel[CFG_SPI_RTC_DEVID], 16, dout, din); + spi_xfer (slave, 16, dout, din, SPI_XFER_BEGIN | SPI_XFER_END); } #endif /* end of code exclusion (see #ifdef CONFIG_SXNI855T above) */ |