timer.c: fixed detection of positive clock skew (and some typos)

git-svn-id: https://ssl.bulix.org/svn/lcd4linux/trunk@1143 3ae390bd-cb1e-0410-b409-cd5a39f66f1f

drv_USBLCD.c

@@ -337,7 +337,7 @@ static int drv_UL_start(const char *section, const int quiet)
     /* Init the command buffer */
     Buffer = (char *) malloc(1024);
     if (Buffer == NULL) {
-	error("%s: coommand buffer could not be allocated: malloc() failed", Name);
+	error("%s: command buffer could not be allocated: malloc() failed", Name);
 	return -1;
     }
     BufPtr = Buffer;

drv_picoLCD.c

@@ -306,7 +306,7 @@ static int drv_pL_start(const char *section, const int quiet)
     /* Init the command buffer */
     Buffer = (char *) malloc(1024);
     if (Buffer == NULL) {
-	error("%s: coommand buffer could not be allocated: malloc() failed", Name);
+	error("%s: command buffer could not be allocated: malloc() failed", Name);
 	return -1;
     }
     BufPtr = Buffer;

drv_picoLCDGraphic.c

@@ -520,7 +520,7 @@ static int drv_pLG_start(const char *section, const int quiet)
     /* Init the command buffer */
     Buffer = (char *) malloc(1024);
     if (Buffer == NULL) {
-	error("%s: coommand buffer could not be allocated: malloc() failed", Name);
+	error("%s: command buffer could not be allocated: malloc() failed", Name);
 	return -1;
     }
     BufPtr = Buffer;

timer.c

@@ -443,16 +443,16 @@ int timer_process(struct timespec *delay)
        in "diff" */
     timersub(&Timers[next_timer].when, &now, &diff);
 
-    /* convert "diff" to milliseconds */
-    int time_difference = (diff.tv_sec * 1000.0f) + (diff.tv_usec / 1000.0f);
-
-    /* a notable negative delay has occurred (positive clock skew or
-       some timers are faster than the time needed for processing
-       their callbacks) */
-    if (time_difference < (-CLOCK_SKEW_DETECT_TIME_IN_MS)) {
+    /* a negative delay has occurred (positive clock skew or some
+       timers are faster than the time needed for processing their
+       callbacks) */
+    if (diff.tv_sec < 0) {
 	/* zero "diff" so the next update is triggered immediately */
 	timerclear(&diff);
     } else {
+	/* convert "diff" to milliseconds */
+	int time_difference = diff.tv_sec * 1000 + diff.tv_usec / 1000;
+
 	/* if there is a notable difference between "time_difference" and
 	   the next upcoming timer's interval, assume clock skew */
 	if (time_difference > (Timers[next_timer].interval + CLOCK_SKEW_DETECT_TIME_IN_MS)) {