diff options
author | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-10-11 19:21:23 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-10-11 19:21:23 -0700 |
commit | dd6d1844af33acb4edd0a40b1770d091a22c94be (patch) | |
tree | e6bd3549919773a13b770324a4dddb51b194b452 /arch/mips/lasat/ds1603.c | |
parent | Merge git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6 (diff) | |
parent | [MIPS] tlbex.c: Cleanup __init usage. (diff) | |
download | linux-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.c | 183 |
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); +} |