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path: root/drivers/rtc/ds1306.c
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Diffstat (limited to 'drivers/rtc/ds1306.c')
-rw-r--r--drivers/rtc/ds1306.c67
1 files changed, 50 insertions, 17 deletions
diff --git a/drivers/rtc/ds1306.c b/drivers/rtc/ds1306.c
index 1c8ac7f..29854fc 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) */