by This is part 3 of 3 of the genrtc patches. This is my own slight bit
of work. This changes set_rtc_time(struct *rtc_time) to return an int
instead of void. This was done so that the arch-specific code here
could do additional checks on the time and return an error if needed.
This then introduces include/asm-generic/rtc.h, include/asm-i386/rtc.h
and include/asm-alpha/rtc.h. include/asm-generic/rtc.h contains the
get_rtc_time and set_rtc_time logic that is in drivers/char/rtc.c,
slightly modified to not duplicate the tests done by the genrtc code but
keeping the additional ones (years > 255 and > 169, as well as the
CONFIG_DECSTATION ones). This portion has been tested on SMP i386.
This also modifies include/asm-ppc/rtc.h to return -EINVAL if no rtc
hardware is present (it would silently fail previously).
--
Tom Rini (TR1265)
http://gate.crashing.org/~trini/
--- linux-2.5/drivers/char/genrtc.c-original 2002-07-24 12:23:40.000000000 -0700
+++ linux-2.5/drivers/char/genrtc.c 2002-07-24 13:22:05.000000000 -0700
@@ -33,9 +33,10 @@
* 1.03 make it more portable zip...@linux-m68k.org
* 1.04 removed useless timer code r...@linux-m68k.org
* 1.05 portable RTC_UIE emulation r...@linux-m68k.org
+ * 1.06 set_rtc_time can return an error tr...@kernel.crashing.org
*/
-#define RTC_VERSION "1.05"
+#define RTC_VERSION "1.06"
#include <linux/module.h>
#include <linux/config.h>
@@ -326,8 +327,7 @@
wtime.tm_sec < 0 || wtime.tm_sec >= 60)
return -EINVAL;
- set_rtc_time(&wtime);
- return 0;
+ return set_rtc_time(&wtime);
}
}
--- linux-2.5/include/asm-ppc/rtc.h-original 2002-07-24 13:25:15.000000000 -0700
+++ linux-2.5/include/asm-ppc/rtc.h 2002-07-24 13:25:36.000000000 -0700
@@ -68,7 +68,10 @@
time->tm_sec);
(ppc_md.set_rtc_time)(nowtime);
- }
+
+ return 0;
+ } else
+ return -EINVAL;
}
static inline unsigned int get_rtc_ss(void)
--- /dev/null 1969-12-31 17:00:00.000000000 -0700
+++ linux-2.5/include/asm-generic/rtc.h 2002-07-24 11:06:48.000000000 -0700
@@ -0,0 +1,211 @@
+/*
+ * inclue/asm-generic/rtc.h
+ *
+ * Author: Tom Rini <tr...@mvista.com>
+ *
+ * Based on:
+ * drivers/char/rtc.c
+ *
+ * Please read the COPYING file for all license details.
+ */
+
+#ifndef __ASM_RTC_H__
+#define __ASM_RTC_H__
+
+#ifdef __KERNEL__
+
+#include <linux/mc146818rtc.h>
+#include <linux/rtc.h>
+
+#define RTC_PIE 0x40 /* periodic interrupt enable */
+#define RTC_AIE 0x20 /* alarm interrupt enable */
+#define RTC_UIE 0x10 /* update-finished interrupt enable */
+
+extern void gen_rtc_interrupt(unsigned long);
+
+/* some dummy definitions */
+#define RTC_SQWE 0x08 /* enable square-wave output */
+#define RTC_DM_BINARY 0x04 /* all time/date values are BCD if clear */
+#define RTC_24H 0x02 /* 24 hour mode - else hours bit 7 means pm */
+#define RTC_DST_EN 0x01 /* auto switch DST - works f. USA only */
+
+/*
+ * Returns true if a clock update is in progress
+ */
+static inline unsigned char rtc_is_updating(void)
+{
+ unsigned char uip;
+
+ spin_lock_irq(&rtc_lock);
+ uip = (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP);
+ spin_unlock_irq(&rtc_lock);
+ return uip;
+}
+
+static inline void get_rtc_time(struct rtc_time *time)
+{
+ unsigned long uip_watchdog = jiffies;
+ unsigned char ctrl;
+#ifdef CONFIG_DECSTATION
+ unsigned int real_year;
+#endif
+
+ /*
+ * read RTC once any update in progress is done. The update
+ * can take just over 2ms. We wait 10 to 20ms. There is no need to
+ * to poll-wait (up to 1s - eeccch) for the falling edge of RTC_UIP.
+ * If you need to know *exactly* when a second has started, enable
+ * periodic update complete interrupts, (via ioctl) and then
+ * immediately read /dev/rtc which will block until you get the IRQ.
+ * Once the read clears, read the RTC time (again via ioctl). Easy.
+ */
+
+ if (rtc_is_updating() != 0)
+ while (jiffies - uip_watchdog < 2*HZ/100) {
+ barrier();
+ cpu_relax();
+ }
+
+ /*
+ * Only the values that we read from the RTC are set. We leave
+ * tm_wday, tm_yday and tm_isdst untouched. Even though the
+ * RTC has RTC_DAY_OF_WEEK, we ignore it, as it is only updated
+ * by the RTC when initially set to a non-zero value.
+ */
+ spin_lock_irq(&rtc_lock);
+ time->tm_sec = CMOS_READ(RTC_SECONDS);
+ time->tm_min = CMOS_READ(RTC_MINUTES);
+ time->tm_hour = CMOS_READ(RTC_HOURS);
+ time->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH);
+ time->tm_mon = CMOS_READ(RTC_MONTH);
+ time->tm_year = CMOS_READ(RTC_YEAR);
+#ifdef CONFIG_DECSTATION
+ real_year = CMOS_READ(RTC_DEC_YEAR);
+#endif
+ ctrl = CMOS_READ(RTC_CONTROL);
+ spin_unlock_irq(&rtc_lock);
+
+ if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
+ {
+ BCD_TO_BIN(time->tm_sec);
+ BCD_TO_BIN(time->tm_min);
+ BCD_TO_BIN(time->tm_hour);
+ BCD_TO_BIN(time->tm_mday);
+ BCD_TO_BIN(time->tm_mon);
+ BCD_TO_BIN(time->tm_year);
+ }
+
+#ifdef CONFIG_DECSTATION
+ time->tm_year += real_year - 72;
+#endif
+
+ /*
+ * Account for differences between how the RTC uses the values
+ * and how they are defined in a struct rtc_time;
+ */
+ if (time->tm_year <= 69)
+ time->tm_year += 100;
+
+ time->tm_mon--;
+}
+
+/* Set the current date and time in the real time clock. */
+static inline int set_rtc_time(struct rtc_time *time)
+{
+ unsigned char mon, day, hrs, min, sec;
+ unsigned char save_control, save_freq_select;
+ unsigned int yrs;
+#ifdef CONFIG_DECSTATION
+ unsigned int real_yrs, leap_yr;
+#endif
+
+ yrs = time->tm_year;
+ mon = time->tm_mon + 1; /* tm_mon starts at zero */
+ day = time->tm_mday;
+ hrs = time->tm_hour;
+ min = time->tm_min;
+ sec = time->tm_sec;
+
+ if (yrs > 255) /* They are unsigned */
+ return -EINVAL;
+
+ spin_lock_irq(&rtc_lock);
+#ifdef CONFIG_DECSTATION
+ real_yrs = yrs;
+ leap_yr = ((!((yrs + 1900) % 4) && ((yrs + 1900) % 100)) ||
+ !((yrs + 1900) % 400));
+ yrs = 72;
+
+ /*
+ * We want to keep the year set to 73 until March
+ * for non-leap years, so that Feb, 29th is handled
+ * correctly.
+ */
+ if (!leap_yr && mon < 3) {
+ real_yrs--;
+ yrs = 73;
+ }
+#endif
+ /* These limits and adjustments are independant of
+ * whether the chip is in binary mode or not.
+ */
+ if (yrs > 169) {
+ spin_unlock_irq(&rtc_lock);
+ return -EINVAL;
+ }
+
+ if (yrs >= 100)
+ yrs -= 100;
+
+ if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY)
+ || RTC_ALWAYS_BCD) {
+ BIN_TO_BCD(sec);
+ BIN_TO_BCD(min);
+ BIN_TO_BCD(hrs);
+ BIN_TO_BCD(day);
+ BIN_TO_BCD(mon);
+ BIN_TO_BCD(yrs);
+ }
+
+ save_control = CMOS_READ(RTC_CONTROL);
+ CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL);
+ save_freq_select = CMOS_READ(RTC_FREQ_SELECT);
+ CMOS_WRITE((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT);
+
+#ifdef CONFIG_DECSTATION
+ CMOS_WRITE(real_yrs, RTC_DEC_YEAR);
+#endif
+ CMOS_WRITE(yrs, RTC_YEAR);
+ CMOS_WRITE(mon, RTC_MONTH);
+ CMOS_WRITE(day, RTC_DAY_OF_MONTH);
+ CMOS_WRITE(hrs, RTC_HOURS);
+ CMOS_WRITE(min, RTC_MINUTES);
+ CMOS_WRITE(sec, RTC_SECONDS);
+
+ CMOS_WRITE(save_control, RTC_CONTROL);
+ CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
+
+ spin_unlock_irq(&rtc_lock);
+
+ return 0;
+}
+
+static inline unsigned int get_rtc_ss(void)
+{
+ struct rtc_time h;
+
+ get_rtc_time(&h);
+ return h.tm_sec;
+}
+
+static inline int get_rtc_pll(struct rtc_pll_info *pll)
+{
+ return -EINVAL;
+}
+static inline int set_rtc_pll(struct rtc_pll_info *pll)
+{
+ return -EINVAL;
+}
+
+#endif /* __KERNEL__ */
+#endif /* __ASM_RTC_H__ */
--- /dev/null 1969-12-31 17:00:00.000000000 -0700
+++ linux-2.5/include/asm-i386/rtc.h 2002-07-23 10:38:32.000000000 -0700
@@ -0,0 +1,10 @@
+#ifndef _I386_RTC_H
+#define _I386_RTC_H
+
+/*
+ * x86 uses the default access methods for the RTC.
+ */
+
+#include <asm-generic/rtc.h>
+
+#endif
--- /dev/null 1969-12-31 17:00:00.000000000 -0700
+++ linux-2.5/include/asm-alpha/rtc.h 2002-07-23 10:38:32.000000000 -0700
@@ -0,0 +1,10 @@
+#ifndef _ALPHA_RTC_H
+#define _ALPHA_RTC_H
+
+/*
+ * Alpha uses the default access methods for the RTC.
+ */
+
+#include <asm-generic/rtc.h>
+
+#endif
-
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