1 files changed, 174 insertions, 0 deletions

diff --git a/arch/mips/lasat/ds1603.c b/arch/mips/lasat/ds1603.c
new file mode 100644
index 000000000000..7bbf6cf923c9
--- /dev/null
+++ b/arch/mips/lasat/ds1603.c
@@ -0,0 +1,174 @@
+/* 
+ * Dallas Semiconductors 1603 RTC driver 
+ *
+ * Brian Murphy <brian@murphy.dk> 
+ *
+ */
+#include <linux/kernel.h>
+#include <asm/lasat/lasat.h>
+#include <linux/delay.h>
+#include <asm/lasat/ds1603.h>
+
+#include "ds1603.h"
+
+#define READ_TIME_CMD 0x81
+#define SET_TIME_CMD 0x80
+#define TRIMMER_SET_CMD 0xC0
+#define TRIMMER_VALUE_MASK 0x38
+#define TRIMMER_SHIFT 3
+
+struct ds_defs *ds1603 = NULL;
+
+/* HW specific register functions */
+static void rtc_reg_write(unsigned long val) 
+{
+        *ds1603->reg = val;
+}
+
+static unsigned long rtc_reg_read(void) 
+{
+        unsigned long tmp = *ds1603->reg;
+        return tmp;
+}
+
+static unsigned long rtc_datareg_read(void)
+{
+        unsigned long tmp = *ds1603->data_reg;
+        return tmp;
+}
+
+static void rtc_nrst_high(void)
+{
+        rtc_reg_write(rtc_reg_read() | ds1603->rst);
+}
+
+static void rtc_nrst_low(void)
+{
+        rtc_reg_write(rtc_reg_read() & ~ds1603->rst);
+}
+
+static void rtc_cycle_clock(unsigned long data)
+{
+        data |= ds1603->clk;
+        rtc_reg_write(data);
+        lasat_ndelay(250);
+        if (ds1603->data_reversed)
+                data &= ~ds1603->data;
+        else
+                data |= ds1603->data;
+        data &= ~ds1603->clk;
+        rtc_reg_write(data);
+        lasat_ndelay(250 + ds1603->huge_delay);
+}
+
+static void rtc_write_databit(unsigned int bit)
+{
+        unsigned long data = rtc_reg_read();
+        if (ds1603->data_reversed)
+                bit = !bit;
+        if (bit)
+                data |= ds1603->data;
+        else
+                data &= ~ds1603->data;
+
+        rtc_reg_write(data);
+        lasat_ndelay(50 + ds1603->huge_delay);
+        rtc_cycle_clock(data);
+}
+
+static unsigned int rtc_read_databit(void)
+{
+        unsigned int data;
+
+        data = (rtc_datareg_read() & (1 << ds1603->data_read_shift)) 
+                >> ds1603->data_read_shift;
+        rtc_cycle_clock(rtc_reg_read());
+        return data;
+}
+
+static void rtc_write_byte(unsigned int byte)
+{
+        int i;
+
+        for (i = 0; i<=7; i++) {
+                rtc_write_databit(byte & 1L);
+                byte >>= 1;
+        }
+}
+
+static void rtc_write_word(unsigned long word)
+{
+        int i;
+
+        for (i = 0; i<=31; i++) {
+                rtc_write_databit(word & 1L);
+                word >>= 1;
+        }
+}
+
+static unsigned long rtc_read_word(void)
+{
+        int i;
+        unsigned long word = 0;
+        unsigned long shift = 0;
+
+        for (i = 0; i<=31; i++) {
+                word |= rtc_read_databit() << shift;
+                shift++;
+        }
+        return word;
+}
+
+static void rtc_init_op(void)
+{
+        rtc_nrst_high();
+
+        rtc_reg_write(rtc_reg_read() & ~ds1603->clk);
+
+        lasat_ndelay(50);
+}
+
+static void rtc_end_op(void)
+{
+        rtc_nrst_low();
+        lasat_ndelay(1000);
+}
+
+/* interface */
+unsigned long ds1603_read(void)
+{
+        unsigned long word;
+        rtc_init_op();
+        rtc_write_byte(READ_TIME_CMD);
+        word = rtc_read_word();
+        rtc_end_op();
+        return word;
+}
+
+int ds1603_set(unsigned long time)
+{
+        rtc_init_op();
+        rtc_write_byte(SET_TIME_CMD);
+        rtc_write_word(time);
+        rtc_end_op();
+
+        return 0;
+}
+
+void ds1603_set_trimmer(unsigned int trimval)
+{
+        rtc_init_op();
+        rtc_write_byte(((trimval << TRIMMER_SHIFT) & TRIMMER_VALUE_MASK)
+                        | (TRIMMER_SET_CMD));
+        rtc_end_op();
+}
+
+void ds1603_disable(void)
+{
+        ds1603_set_trimmer(TRIMMER_DISABLE_RTC);
+}
+
+void ds1603_enable(void)
+{
+        ds1603_set_trimmer(TRIMMER_DEFAULT);
+}