# $Id: openbsd-acpithinkpad_brightness_fix.diff,v 1.1 2008/12/16 22:19:58 jcs Exp $
#
# make acpithinkpad(4) handle brightness adjustments properly on the
# x61s and t61.  on those two models, it still uses the brightness
# adjustment callback to adjust inside the driver.  this fixes the
# double adjustment problem on newer models while still working on
# these two quirky models.
#
# jcs@openbsd.org
#

Index: acpithinkpad.c
===================================================================
RCS file: /cvs/src/sys/dev/acpi/acpithinkpad.c,v
retrieving revision 1.13
diff -u -p -r1.13 acpithinkpad.c
--- acpithinkpad.c	6 Nov 2008 23:41:28 -0000	1.13
+++ acpithinkpad.c	16 Dec 2008 22:18:07 -0000
@@ -32,6 +32,9 @@
 #define	THINKPAD_CMOS_BRIGHTNESS_UP	0x04
 #define	THINKPAD_CMOS_BRIGHTNESS_DOWN	0x05
 
+#define	THINKPAD_EC_BRIGHTNESS_OFFSET	0x31
+#define	THINKPAD_EC_BRIGHTNESS_LEVEL_MASK 0x1f
+
 #define	THINKPAD_BLUETOOTH_PRESENT	0x01
 #define	THINKPAD_BLUETOOTH_ENABLED	0x02
 
@@ -82,6 +85,17 @@ struct acpithinkpad_softc {
 	struct aml_node		*sc_devnode;
 };
 
+/* from bios.c */
+extern char *hw_ver;
+
+/* models (according to smbios info version) that need a brightness helper */
+const char *acpithinkpad_models_to_help[] = {
+	"ThinkPad X61s",
+	"ThinkPad T61",
+};
+
+int	thinkpad_need_helper = 0;
+
 int	thinkpad_match(struct device *, void *, void *);
 void	thinkpad_attach(struct device *, struct device *, void *);
 int	thinkpad_hotkey(struct aml_node *, int, void *);
@@ -92,8 +106,9 @@ 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_up(struct acpithinkpad_softc *);
+int	thinkpad_brightness_get(struct acpithinkpad_softc *);
 int	thinkpad_brightness_down(struct acpithinkpad_softc *);
+int	thinkpad_brightness_up(struct acpithinkpad_softc *);
 
 struct cfattach acpithinkpad_ca = {
 	sizeof(struct acpithinkpad_softc), thinkpad_match, thinkpad_attach
@@ -132,11 +147,22 @@ 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");
+	for (i = 0; i < nitems(acpithinkpad_models_to_help); i++)
+		if (strcmp(hw_ver, acpithinkpad_models_to_help[i]) == 0) {
+			printf(": activating brightness helper");
+			thinkpad_need_helper = 1;
+			break;
+		}
+
+	/* 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);
@@ -144,6 +170,8 @@ 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_NOPOLL);
+
+	printf("\n");
 }
 
 int
@@ -203,6 +231,7 @@ thinkpad_hotkey(struct aml_node *node, i
 		if (aml_evalname(sc->sc_acpi, sc->sc_devnode, "MHKP", 0, NULL,
 		    &res))
 			goto done;
+
 		val = aml_val2int(&res);
 		aml_freevalue(&res);
 		if (val == 0)
@@ -215,25 +244,27 @@ thinkpad_hotkey(struct aml_node *node, i
 		switch (type) {
 		case 1:
 			switch (event) {
-			case THINKPAD_BUTTON_BRIGHTNESS_UP:
-				thinkpad_brightness_up(sc);
-				handled = 1;
-				break;
-			case THINKPAD_BUTTON_BRIGHTNESS_DOWN:
-				thinkpad_brightness_down(sc);
-				handled = 1;
-				break;
 			case THINKPAD_BUTTON_WIRELESS:
 				thinkpad_toggle_bluetooth(sc);
 				handled = 1;
 				break;
 			case THINKPAD_BUTTON_SUSPEND:
 				handled = 1;
-				/* 
+				/*
 				acpi_enter_sleep_state(sc->sc_acpi,
 				    ACPI_STATE_S3);
 				*/
 				break;
+			case THINKPAD_BUTTON_BRIGHTNESS_UP:
+				if (thinkpad_need_helper)
+					thinkpad_brightness_up(sc);
+				handled = 1;
+				break;
+			case THINKPAD_BUTTON_BRIGHTNESS_DOWN:
+				if (thinkpad_need_helper)
+					thinkpad_brightness_down(sc);
+				handled = 1;
+				break;
 			case THINKPAD_BUTTON_HIBERNATE:
 			case THINKPAD_BUTTON_FN_F1:
 			case THINKPAD_BUTTON_LOCK_SCREEN:
@@ -318,8 +349,10 @@ thinkpad_toggle_bluetooth(struct acpithi
 	bluetooth = aml_val2int(&res);
 	aml_freevalue(&res);
 
-	if (!(bluetooth & THINKPAD_BLUETOOTH_PRESENT))
+	if (!(bluetooth & THINKPAD_BLUETOOTH_PRESENT)) {
+		printf("no bluetooth present\n");
 		goto fail;
+	}
 
 	bzero(&arg, sizeof(arg));
 	arg.type = AML_OBJTYPE_INTEGER;
@@ -338,7 +371,7 @@ int
 thinkpad_toggle_wan(struct acpithinkpad_softc *sc)
 {
 	struct aml_value	res, arg;
-	int			wan, rv = 1;;
+	int			wan, rv = 1;
 
 	if (aml_evalname(sc->sc_acpi, sc->sc_devnode, "GWAN", 0, NULL, &res))
 		goto fail;
@@ -395,6 +428,18 @@ int
 thinkpad_volume_mute(struct acpithinkpad_softc *sc)
 {
 	return (thinkpad_cmos(sc, THINKPAD_CMOS_VOLUME_MUTE));
+}
+
+int
+thinkpad_brightness_get(struct acpithinkpad_softc *sc)
+{
+	uint8_t val;
+	int level;
+
+	acpiec_read(sc->sc_acpi->sc_ec, THINKPAD_EC_BRIGHTNESS_OFFSET, 1, &val);
+	level = val & THINKPAD_EC_BRIGHTNESS_LEVEL_MASK;
+
+	return level;
 }
 
 int