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authorLinus Torvalds <torvalds@woody.linux-foundation.org>2007-10-11 19:21:23 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-10-11 19:21:23 -0700
commitdd6d1844af33acb4edd0a40b1770d091a22c94be (patch)
treee6bd3549919773a13b770324a4dddb51b194b452 /arch/mips/lasat/ds1603.c
parentMerge git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6 (diff)
parent[MIPS] tlbex.c: Cleanup __init usage. (diff)
downloadlinux-dev-dd6d1844af33acb4edd0a40b1770d091a22c94be.tar.xz
linux-dev-dd6d1844af33acb4edd0a40b1770d091a22c94be.zip
Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus: (80 commits) [MIPS] tlbex.c: Cleanup __init usage. [MIPS] WRPPMC serial support move to platform device [MIPS] R1: Fix hazard barriers to make kernels work on R2 also. [MIPS] VPE: reimplement ELF loader. [MIPS] cleanup WRPPMC include files [MIPS] Add BUG_ON assertion for attempt to run kernel on the wrong CPU type. [MIPS] SMP: Use ISO C struct initializer for local structs. [MIPS] SMP: Kill useless casts. [MIPS] Kill num_online_cpus() loops. [MIPS] SMP: Implement smp_call_function_mask(). [MIPS] Make facility to convert CPU types to strings generally available. [MIPS] Convert list of CPU types from #define to enum. [MIPS] Optimize get_unaligned / put_unaligned implementations. [MIPS] checkfiles: Fix "need space after that ','" errors. [MIPS] Fix "no space between function name and open parenthesis" warnings. [MIPS] Allow hardwiring of the CPU type to a single type for optimization. [MIPS] tlbex: Size optimize code by declaring a few functions inline. [MIPS] pg-r4k.c: Dump the generated code [MIPS] Cobalt: Remove cobalt_machine_power_off() [MIPS] Cobalt: Move reset port definition to arch/mips/cobalt/reset.c ...
Diffstat (limited to 'arch/mips/lasat/ds1603.c')
-rw-r--r--arch/mips/lasat/ds1603.c183
1 files changed, 183 insertions, 0 deletions
diff --git a/arch/mips/lasat/ds1603.c b/arch/mips/lasat/ds1603.c
new file mode 100644
index 000000000000..52cb1436a12a
--- /dev/null
+++ b/arch/mips/lasat/ds1603.c
@@ -0,0 +1,183 @@
+/*
+ * 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 <asm/time.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;
+
+/* 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);
+}
+
+unsigned long read_persistent_clock(void)
+{
+ unsigned long word;
+ unsigned long flags;
+
+ spin_lock_irqsave(&rtc_lock, flags);
+ rtc_init_op();
+ rtc_write_byte(READ_TIME_CMD);
+ word = rtc_read_word();
+ rtc_end_op();
+ spin_unlock_irqrestore(&rtc_lock, flags);
+
+ return word;
+}
+
+int rtc_mips_set_mmss(unsigned long time)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&rtc_lock, flags);
+ rtc_init_op();
+ rtc_write_byte(SET_TIME_CMD);
+ rtc_write_word(time);
+ rtc_end_op();
+ spin_unlock_irqrestore(&rtc_lock, flags);
+
+ 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);
+}