Complete RTC clock fixes so tha the sync API is fully functional.

BKrev: 4294e0edD2vuJeMjgJ79D02-WIUu4w

diff --git a/packages/linux/openslug-kernel-2.6.11.2/x1205-rtc.c b/packages/linux/openslug-kernel-2.6.11.2/x1205-rtc.c
index 7330037..acac095 100644 (file)
--- a/packages/linux/openslug-kernel-2.6.11.2/x1205-rtc.c
+++ b/packages/linux/openslug-kernel-2.6.11.2/x1205-rtc.c
@@ -351,62 +351,37 @@ static int x1205_detach(struct i2c_client *client)
 // make sure the rtc_time values are in bounds
 static int x1205_validate_tm(struct rtc_time *tm, int datetoo)
 {
-       int result = NOERR;
-
-       tm->tm_year += epoch;
-
-       /* The RTC uses a byte containing a BCD year value, so this is
-        * limited to the range 0..99 from rtc_epoch.
-        */
-       if (tm->tm_year < rtc_epoch || tm->tm_year > rtc_epoch + 99)
-               goto baddate;
-
-       if ((tm->tm_mon > 11) || tm->tm_mon < 0 || (tm->tm_mday == 0))
-               goto baddate;
-
-       if (tm->tm_mday < 0)
-               goto baddate;
-
-       if (tm->tm_mday > (days_in_mo[tm->tm_mon] + ( (tm->tm_mon == 1) && 
-               ((!(tm->tm_year % 4) && (tm->tm_year % 100) ) || !(tm->tm_year % 400)))))
-               goto baddate;
-
-       /* This special check shouldn't fire, it's here to detect a possible invalid
-        * input which seems to happen to the clock on shutdown (detach?)
-        */
-       if (tm->tm_year == rtc_epoch && tm->tm_mon == 0 && tm->tm_mday == 0) {
-               printk(KERN_DEBUG "x1205_validate_tm: date is being zapped\n");
-               /* FIXME: this is a hack to test the problem. */
-               tm->tm_year = rtc_epoch+45-epoch;
-               return NOERR;
-
-       baddate:
-               if (datetoo) {
+       if (datetoo) {
+               /* This used to be 1900, not epoch, but all the read APIs subtract
+                * epoch, not 1900, and the result of these APIs *is* fed back in
+                * to x1205_command (which calls this.)
+                */
+               tm->tm_year += epoch;
+
+               /* The RTC uses a byte containing a BCD year value, so this is
+                * limited to the range 0..99 from rtc_epoch.
+                */
+               if ((tm->tm_year < rtc_epoch || tm->tm_year > rtc_epoch + 99) ||
+                       ((tm->tm_mon > 11) || tm->tm_mon < 0 || (tm->tm_mday <= 0)) ||
+                       (tm->tm_mday > (days_in_mo[tm->tm_mon] + ( (tm->tm_mon == 1) && 
+                       ((!(tm->tm_year % 4) && (tm->tm_year % 100) ) || !(tm->tm_year % 400)))))
+                       ) {
                        printk(KERN_DEBUG "x1205_validate_tm: invalid date:\t%04d,%02d,%02d\n",
-                               tm->tm_year, tm->tm_mon, tm->tm_mday);
+                                       tm->tm_year, tm->tm_mon, tm->tm_mday);
                        return -EINVAL;
-               } else {
-                       /* I believe this case is the one where the kernel crashed
-                        * because tm_mon is large and negative (uninitialised).
-                        */
-                       printk(KERN_DEBUG "x1205_validate_tm: unset date:\t%04d,%02d,%02d\n",
-                               tm->tm_year, tm->tm_mon, tm->tm_mday);
                }
-       }
-
-       tm->tm_year -= epoch;
 
-       if ((tm->tm_hour < 0) || (tm->tm_min < 0) || (tm->tm_sec < 0))
-               result = -EINVAL;
-       if ((tm->tm_hour >= 24) || (tm->tm_min >= 60) || (tm->tm_sec >= 60))
-               result = -EINVAL;
+               tm->tm_year -= epoch;
+       }
 
-       if (result == -EINVAL) {
+       if (((tm->tm_hour < 0) || (tm->tm_min < 0) || (tm->tm_sec < 0)) ||
+               ((tm->tm_hour >= 24) || (tm->tm_min >= 60) || (tm->tm_sec >= 60))) {
                printk(KERN_DEBUG "x1205_validate_tm: invalid time:\t%02d,%02d,%02d\n",
                        tm->tm_hour, tm->tm_min, tm->tm_sec);
+               return -EINVAL;
        }
 
-       return result;
+       return NOERR;
 }
 
 static int x1205_command(struct i2c_client *client, unsigned int cmd, void *tm)
@@ -486,20 +461,80 @@ static int x1205_sync_rtc(void)
         * that this will tend to fire for small drifts close to UTC midnight.
         */
        cmd = RTC_SETTIME;
-       div = new_s - mktime(tm.tm_year+epoch, tm.tm_mon+1, tm.tm_mday,
+       rem = new_s - mktime(tm.tm_year+epoch, tm.tm_mon+1, tm.tm_mday,
+                               tm.tm_hour, tm.tm_min, tm.tm_sec);
+       if (rem != 0) {
+               int dif;
+
+               /* Make an approximation to year/month/day. */
+               rem = div;
+               div = (2*div)/61;  // 30.5 days/month
+               tm.tm_mday = 1 + rem - (div*61)/2;
+               rem = div;
+               div /= 12;
+               rem -= 12*div;
+               while (tm.tm_mday > days_in_mo[rem]) {
+                       tm.tm_mday -= days_in_mo[rem];
+                       if (++rem >= 12) {
+                               rem -= 12;
+                               ++div;
+                       }
+               }
+               tm.tm_mon = rem;
+               div += 1970;       // base of tv_sec
+
+               /* Calculate the error in the approximation as a signed
+                * int value.
+                */
+               dif = new_s - mktime(div, tm.tm_mon+1, tm.tm_mday,
                                tm.tm_hour, tm.tm_min, tm.tm_sec);
-       if (div != 0) {
-               /* Convert to days. */
-               printk(KERN_DEBUG "x1205_sync_rtc exit (change tm_mday %d)\n",
-                       div);
-               div /= 86400;
-               if (div <= 0) --div;
+               while (dif < 0) {
+                       --(tm.tm_mday);
+                       dif += 86400;
+               }
+               while (dif >= 86400) {
+                       ++(tm.tm_mday);
+                       dif -= 86400;
+               }
+               if (dif != 0)
+                       printk(KERN_ERR "x1205_sync_rtc (error in date %d)\n", dif);
+
+               /* Normalise the result. */
+               while (tm.tm_mday <= 0) {
+                       if (--(tm.tm_mon) < 0) {
+                               tm.tm_mon += 12;
+                               --div;
+                       }
+                       tm.tm_mday += days_in_mo[tm.tm_mon] + (tm.tm_mon==1 &&
+                               ((!(div % 4) && (div % 100) ) || !(div % 400)));
+               }
+
+               do {
+                       rem = days_in_mo[tm.tm_mon] + (tm.tm_mon==1 &&
+                               ((!(div % 4) && (div % 100) ) || !(div % 400)));
+                       if (tm.tm_mday > rem) {
+                               tm.tm_mday -= rem;
+                               if (++(tm.tm_mon) >= 12) {
+                                       tm.tm_mon -= 12;
+                                       ++div;
+                               }
+                       } else {
+                               break;
+                       }
+               } while (1);
+
+               tm.tm_year = div-epoch;
                cmd = RTC_SETDATETIME;
-               return 1;
+               printk(KERN_DEBUG "x1205_sync_rtc exit (change date %d)\n", new_s-old_s);
+       } else {
+               printk(KERN_DEBUG "x1205_sync_rtc exit (change seconds %d)\n", new_s-old_s);
+               /* But avoid the race condition when the date is about to
+                * change.
+                */
+               if (tm.tm_min == 59 && tm.tm_hour == 23)
+                       cmd = RTC_SETDATETIME;
        }
 
-       printk(KERN_DEBUG "x1205_sync_rtc exit (change seconds %d)\n", new_s-old_s);
-
        return x1205_command(&x1205_i2c_client, cmd, &tm);
 }
 

diff --git a/packages/linux/openslug-kernel_2.6.11.2.bb b/packages/linux/openslug-kernel_2.6.11.2.bb
index 0bf4317..d91149d 100644 (file)
--- a/packages/linux/openslug-kernel_2.6.11.2.bb
+++ b/packages/linux/openslug-kernel_2.6.11.2.bb
@@ -2,7 +2,7 @@ SECTION = "kernel"
 DESCRIPTION = "Linux kernel for the Linksys NSLU2 device"
 LICENSE = "GPL"
 MAINTAINER = "Chris Larson <kergoth@handhelds.org>"
-PR = "r8"
+PR = "r9"
 
 KERNEL_SUFFIX = "openslug"