at the end of this mail is an apm kernel patch for 2.2.12 (I386 arch).
it compute the time left of the battery if the bios dont do it (but
provide the % off the battery used).
it is done just after the apm bios is called in apm_get_info().
there is a new configuration option in the APM config menu to
activacte it.
with it i have now the time left of my battery on my Gateway 3100
when using the tools apm or wmapm.
the estimation is done by looking at how many time it take to decremente
the battery by 1%.
the modified files are :
arch/i386/kernel/apm.c
arch/i386/config.in
Documentation/Configure.help
Franck
========== the patch ==============
--- linux.old/arch/i386/config.in Thu Sep 30 21:00:24 1999
+++ linux/arch/i386/config.in Thu Sep 30 21:08:29 1999
@@ -114,6 +114,7 @@
bool ' Ignore multiple suspend/resume cycles' CONFIG_APM_IGNORE_SUSPEND_BOUNCE
bool ' RTC stores time in GMT' CONFIG_APM_RTC_IS_GMT
bool ' Allow interrupts during APM BIOS calls' CONFIG_APM_ALLOW_INTS
+ bool ' Compute Battery time left (when BIOS do not provide the info)' CONFIG_APM_COMPUTE_TIME_LEFT
fi
endmenu
--- linux.old/arch/i386/kernel/apm.c Tue Sep 21 21:23:47 1999
+++ linux/arch/i386/kernel/apm.c Thu Sep 30 21:01:53 1999
@@ -90,6 +90,9 @@
* Use CONFIG_SMP instead of __SMP__
* Ignore BOUNCES for three seconds.
* Stephen Rothwell
+ * 1.10?:Added computing of possible time left for the battery
+ * when the bios return only the the % of the battery.
+ * Franck Sicard <Franck.Sicard@solsoft.fr>
*
* APM 1.1 Reference:
*
@@ -128,6 +131,7 @@
#include <linux/miscdevice.h>
#include <linux/apm_bios.h>
#include <linux/init.h>
+#include <linux/sched.h>
#include <asm/system.h>
#include <asm/uaccess.h>
@@ -1178,6 +1182,10 @@
return 0;
}
+#ifdef CONFIG_APM_COMPUTE_TIME_LEFT
+static int compute_baterry_life(int battery_percentage);
+#endif
+
int apm_get_info(char *buf, char **start, off_t fpos, int length, int dummy)
{
char * p;
@@ -1210,6 +1218,12 @@
time_units = dx & 0x7fff;
}
}
+#ifdef CONFIG_APM_COMPUTE_TIME_LEFT
+ if ((percentage !=-1) && (time_units==-1)) {
+ time_units=compute_baterry_life(percentage);
+ units="min";
+ }
+#endif
}
/* Arguments, with symbols from linux/apm_bios.h. Information is
from the Get Power Status (0x0a) call unless otherwise noted.
@@ -1473,3 +1487,38 @@
apm_enabled = 1;
}
+
+#ifdef CONFIG_APM_COMPUTE_TIME_LEFT
+/* compute time left battery for buggy
+ * APM Bios (=my gateway 3100)
+ */
+static int compute_baterry_life(int battery_percentage)
+{
+ static int old_battery_percentage=-1;
+ static int old_time=0;
+ int new_time;
+ static int time_left;
+
+ if (battery_percentage != old_battery_percentage) {
+ new_time=CURRENT_TIME;
+ if (old_battery_percentage == -1) {
+ /* first call */
+ time_left= -1;
+ } else {
+ /* computing the number of second for 1 % */
+ time_left = (new_time - old_time)/(battery_percentage-old_battery_percentage);
+ /* computing the time left */
+ if (time_left<0) {
+ time_left *=-battery_percentage;
+ } else {
+ time_left *= (100- battery_percentage);
+ }
+ }
+ time_left/=60 /* time left in minutes */;
+ old_battery_percentage = battery_percentage;
+ old_time=new_time;
+ //printk(KERN_INFO "apm: time left %d%% at %d = %ds\n",old_battery_percentage,old_time,time_left);
+ }
+ return time_left;
+}
+#endif
--- linux.old/Documentation/Configure.help Thu Sep 30 21:00:04 1999
+++ linux/Documentation/Configure.help Thu Sep 30 21:07:57 1999
@@ -8993,6 +8993,13 @@
many of the newer IBM Thinkpads. If you experience hangs when you
suspend, try setting this to Y. Otherwise, say N.
+Compute Battery time left (when BIOS do not provide the info)
+CONFIG_APM_COMPUTE_TIME_LEFT
+ if you BIOS doesn't report the time left of your battery, but report
+ the current capacity of the battery, the kernel will compute an
+ estimation of the battery time left. Should be left to N with a
+ good BIOS.
+
Watchdog Timer Support
CONFIG_WATCHDOG
If you say Y here (and to one of the following options) and create a
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/