# $Id: openbsd-acpithinkpad_fan_control.diff,v 1.2 2009/12/30 04:55:24 jcs Exp $
#
# add semi-automated fan control to openbsd's acpithinkpad(4) based on maximum
# temperature readings from all of its sensors.  when the temperature is within
# certain ranges, set the fan control down to level 1 or 2.  if it gets too hot
# (or no temperature readings come back) fallback on the EC's auto mode which is
# what it is in by default (but is quite loud).
#
# this may melt your machine, so use it at your own risk.  only tested on an
# x301.  it could probably use a smarter algorithm to run the fan longer before
# dialing down the setting to avoid constantly flipping back and forth while
# hovering around one of the max temp settings.
#
# this also resurrects my old diff to make acpithinkpad(4) handle brightness
# adjustments properly on newer thinkpads.  on the x61s and t61, it still uses
# the brightness adjustment callback to adjust inside the driver, but on newer
# machines it lets the EC handle adjustments on its own.  this fixes a
# double-adjustment problem in the in-tree version (as of 1.22).
#
# jcs@openbsd.org
#

Index: acpithinkpad.c
===================================================================
RCS file: /cvs/src/sys/dev/acpi/acpithinkpad.c,v
retrieving revision 1.22
diff -u -p -r1.22 acpithinkpad.c
--- acpithinkpad.c	25 Nov 2009 18:57:02 -0000	1.22
+++ acpithinkpad.c	30 Dec 2009 04:44:01 -0000
@@ -68,11 +68,23 @@
 #define	THINKPAD_POWER_CHANGED		0x6030
 #define	THINKPAD_SWITCH_WIRELESS	0x7000
 
-#define THINKPAD_NSENSORS 9
-#define THINKPAD_NTEMPSENSORS 8
+#define	THINKPAD_NSENSORS		9
+#define	THINKPAD_NTEMPSENSORS		8
 
-#define THINKPAD_ECOFFSET_FANLO		0x84
-#define THINKPAD_ECOFFSET_FANHI		0x85
+#define	THINKPAD_ECBRIGHTNESS_OFFSET	0x31
+#define	THINKPAD_ECBRIGHTNESS_LEVEL_MASK 0x1f
+
+#define	THINKPAD_ECOFFSET_FANLO		0x84
+#define	THINKPAD_ECOFFSET_FANHI		0x85
+
+#define	THINKPAD_ECOFFSET_FANLEVEL	0x2f
+
+#define	THINKPAD_ECFANLEVEL_AUTO	7
+
+/* highest temperatures (from any sensor) allowed at each fan level (after
+ * level 2's max temp, it will be put in auto mode) */
+#define	THINKPAD_MAX_TEMP_LEVEL1	55
+#define	THINKPAD_MAX_TEMP_LEVEL2	65
 
 struct acpithinkpad_softc {
 	struct device		 sc_dev;
@@ -85,6 +97,15 @@ struct acpithinkpad_softc {
 	struct ksensordev	 sc_sensdev;
 };
 
+/* models (according to smbios version in bios.c) that need a brightness helper */
+extern char *hw_ver;
+const char *acpithinkpad_models_to_help[] = {
+	"ThinkPad X61s",
+	"ThinkPad T61",
+};
+
+int	thinkpad_need_helper = 0;
+
 extern void acpiec_read(struct acpiec_softc *, u_int8_t, int, u_int8_t *);
 
 int	thinkpad_match(struct device *, void *, void *);
@@ -97,8 +118,10 @@ int	thinkpad_cmos(struct acpithinkpad_so
 int	thinkpad_volume_down(struct acpithinkpad_softc *);
 int	thinkpad_volume_up(struct acpithinkpad_softc *);
 int	thinkpad_volume_mute(struct acpithinkpad_softc *);
+int	thinkpad_brightness_get(struct acpithinkpad_softc *);
 int	thinkpad_brightness_up(struct acpithinkpad_softc *);
 int	thinkpad_brightness_down(struct acpithinkpad_softc *);
+void	thinkpad_set_fan_level(struct acpithinkpad_softc *, int);
 
 void    thinkpad_sensor_attach(struct acpithinkpad_softc *sc);
 void    thinkpad_sensor_refresh(void *);
@@ -155,13 +178,16 @@ thinkpad_sensor_attach(struct acpithinkp
 	sensor_attach(&sc->sc_sensdev, &sc->sc_sens[i]);
 
 	sensordev_install(&sc->sc_sensdev);
+
+	/* initialize fan level to auto */
+	thinkpad_set_fan_level(sc, THINKPAD_ECFANLEVEL_AUTO);
 }
 
 void
 thinkpad_sensor_refresh(void *arg)
 {
 	struct acpithinkpad_softc *sc = arg;
-	u_int8_t lo, hi, i;
+	u_int8_t lo, hi, i, fanlevel, maxtemp = 0;
 	int64_t tmp;
 	char sname[5];
 
@@ -173,12 +199,43 @@ thinkpad_sensor_refresh(void *arg)
 		sc->sc_sens[i].value = (tmp * 1000000) + 273150000;
 		if (tmp > 127 || tmp < -127)
 			sc->sc_sens[i].flags = SENSOR_FINVALID;
+		else if (tmp > maxtemp)
+			maxtemp = tmp;
 	}
 
 	/* Read fan RPM */
 	acpiec_read(sc->sc_ec, THINKPAD_ECOFFSET_FANLO, 1, &lo);
 	acpiec_read(sc->sc_ec, THINKPAD_ECOFFSET_FANHI, 1, &hi);
 	sc->sc_sens[i].value = ((hi << 8L) + lo);
+
+	/* read fan level */
+	acpiec_read(sc->sc_ec, THINKPAD_ECOFFSET_FANLEVEL, 1, &fanlevel);
+
+	/* set the level according to the highest temperature just seen */
+	if (!maxtemp || (maxtemp > THINKPAD_MAX_TEMP_LEVEL2)) {
+		if (fanlevel != THINKPAD_ECFANLEVEL_AUTO) {
+			printf("%s: temperature over %d, changing level to "
+				"auto\n", DEVNAME(sc),
+				THINKPAD_MAX_TEMP_LEVEL2);
+			thinkpad_set_fan_level(sc, THINKPAD_ECFANLEVEL_AUTO);
+		}
+	}
+	
+	else if (maxtemp > THINKPAD_MAX_TEMP_LEVEL1) {
+		if (fanlevel != 2) {
+			printf("%s: temperature over %d, changing level to 2\n",
+				DEVNAME(sc), THINKPAD_MAX_TEMP_LEVEL1);
+			thinkpad_set_fan_level(sc, 2);
+		}
+	}
+
+	else if (maxtemp <= THINKPAD_MAX_TEMP_LEVEL1) {
+		if (fanlevel != 1) {
+			printf("%s: temperature under %d, changing level to "
+				"1\n", DEVNAME(sc), THINKPAD_MAX_TEMP_LEVEL1);
+			thinkpad_set_fan_level(sc, 1);
+		}
+	}
 }
 
 void
@@ -186,11 +243,24 @@ thinkpad_attach(struct device *parent, s
 {
 	struct acpithinkpad_softc *sc = (struct acpithinkpad_softc *)self;
 	struct acpi_attach_args	*aa = aux;
+	int i;
 
 	sc->sc_acpi = (struct acpi_softc *)parent;
 	sc->sc_devnode = aa->aaa_node;
 
-	printf("\n");
+	if (hw_ver) {
+		for (i = 0; i < nitems(acpithinkpad_models_to_help); i++)
+			if (!strcmp(hw_ver, acpithinkpad_models_to_help[i])) {
+				thinkpad_need_helper = 1;
+				break;
+			}
+	} else
+		thinkpad_need_helper = 1;
+
+	/* for models that don't need a brightness helper, adjust brightness on
+	 * our own */
+	if (!thinkpad_need_helper)
+		thinkpad_brightness_get(sc);
 
 	/* Set event mask to receive everything */
 	thinkpad_enable_events(sc);
@@ -199,6 +269,8 @@ thinkpad_attach(struct device *parent, s
 	/* Run thinkpad_hotkey on button presses */
 	aml_register_notify(sc->sc_devnode, aa->aaa_dev,
 	    thinkpad_hotkey, sc, ACPIDEV_POLL);
+
+	printf("\n");
 }
 
 int
@@ -267,11 +339,13 @@ thinkpad_hotkey(struct aml_node *node, i
 
 		switch (event) {
 		case THINKPAD_BUTTON_BRIGHTNESS_UP:
-			thinkpad_brightness_up(sc);
+			if (thinkpad_need_helper)
+				thinkpad_brightness_up(sc);
 			handled = 1;
 			break;
 		case THINKPAD_BUTTON_BRIGHTNESS_DOWN:
-			thinkpad_brightness_down(sc);
+			if (thinkpad_need_helper)
+				thinkpad_brightness_down(sc);
 			handled = 1;
 			break;
 		case THINKPAD_BUTTON_WIRELESS:
@@ -420,6 +494,18 @@ thinkpad_volume_mute(struct acpithinkpad
 }
 
 int
+thinkpad_brightness_get(struct acpithinkpad_softc *sc)
+{
+	uint8_t val;
+	int level;
+
+	acpiec_read(sc->sc_acpi->sc_ec, THINKPAD_ECBRIGHTNESS_OFFSET, 1, &val);
+	level = val & THINKPAD_ECBRIGHTNESS_LEVEL_MASK;
+
+	return level;
+}
+
+int
 thinkpad_brightness_up(struct acpithinkpad_softc *sc)
 {
 	return (thinkpad_cmos(sc, THINKPAD_CMOS_BRIGHTNESS_UP));
@@ -429,4 +515,13 @@ int
 thinkpad_brightness_down(struct acpithinkpad_softc *sc)
 {
 	return (thinkpad_cmos(sc, THINKPAD_CMOS_BRIGHTNESS_DOWN));
+}
+
+void
+thinkpad_set_fan_level(struct acpithinkpad_softc *sc, int level)
+{
+	u_int8_t fan[0];
+
+	fan[0] = level;
+	acpiec_write(sc->sc_ec, THINKPAD_ECOFFSET_FANLEVEL, 1, fan);
 }