[PATCH RFT] fujitsu-laptop: Simplify SBLL/SBL2 backlight handling

[Tony Vroon <tony@linx.net>]

GBLS and GBLL only differ in the clearing of the GHKS flag, so there is no need 
to have two backlight level readouts. Also, per Peter Gruber, the need for the 
BLNF check has disappeared.
As a result, cleanups can be made in the code. This is tested on the S6420 
platform and causes no functionality regressions, on the console without X or 
within X. One module parameter to disable the hotkeys is dropped, I would like 
to instead depend on ACPI_VIDEO.

(Awaiting Tested-by from Peter for the S6410)

Signed-off-by: Tony Vroon <tony@linx.net>

--- linux-2.6/drivers/misc/fujitsu-laptop.c.upstream	2009-01-05 20:34:42.000000000 +0000
+++ linux-2.6/drivers/misc/fujitsu-laptop.c	2009-01-05 20:59:36.000000000 +0000
@@ -155,7 +155,6 @@
 
 static struct fujitsu_t *fujitsu;
 static int use_alt_lcd_levels = -1;
-static int disable_brightness_keys = -1;
 static int disable_brightness_adjust = -1;
 
 /* Device used to access other hotkeys on the laptop */
@@ -413,36 +412,11 @@
 	return fujitsu->max_brightness;
 }
 
-static int get_lcd_level_alt(void)
-{
-	unsigned long long state = 0;
-	acpi_status status = AE_OK;
-
-	vdbg_printk(FUJLAPTOP_DBG_TRACE, "get lcd level via GBLS\n");
-
-	status =
-	    acpi_evaluate_integer(fujitsu->acpi_handle, "GBLS", NULL, &state);
-	if (status < 0)
-		return status;
-
-	fujitsu->brightness_level = state & 0x0fffffff;
-
-	if (state & 0x80000000)
-		fujitsu->brightness_changed = 1;
-	else
-		fujitsu->brightness_changed = 0;
-
-	return fujitsu->brightness_level;
-}
-
 /* Backlight device stuff */
 
 static int bl_get_brightness(struct backlight_device *b)
 {
-	if (use_alt_lcd_levels)
-		return get_lcd_level_alt();
-	else
-		return get_lcd_level();
+	return get_lcd_level();
 }
 
 static int bl_update_status(struct backlight_device *b)
@@ -509,10 +483,7 @@
 
 	int ret;
 
-	if (use_alt_lcd_levels)
-		ret = get_lcd_level_alt();
-	else
-		ret = get_lcd_level();
+	ret = get_lcd_level();
 	if (ret < 0)
 		return ret;
 
@@ -537,10 +508,7 @@
 	if (ret < 0)
 		return ret;
 
-	if (use_alt_lcd_levels)
-		ret = get_lcd_level_alt();
-	else
-		ret = get_lcd_level();
+	ret = get_lcd_level();
 	if (ret < 0)
 		return ret;
 
@@ -622,24 +590,16 @@
 static void dmi_check_cb_common(const struct dmi_system_id *id)
 {
 	acpi_handle handle;
-	int have_blnf;
 	printk(KERN_INFO "fujitsu-laptop: Identified laptop model '%s'.\n",
 	       id->ident);
-	have_blnf = ACPI_SUCCESS
-	    (acpi_get_handle(NULL, "\\_SB.PCI0.GFX0.LCD.BLNF", &handle));
 	if (use_alt_lcd_levels == -1) {
-		vdbg_printk(FUJLAPTOP_DBG_TRACE, "auto-detecting usealt\n");
-		use_alt_lcd_levels = 1;
-	}
-	if (disable_brightness_keys == -1) {
-		vdbg_printk(FUJLAPTOP_DBG_TRACE,
-			    "auto-detecting disable_keys\n");
-		disable_brightness_keys = have_blnf ? 1 : 0;
-	}
-	if (disable_brightness_adjust == -1) {
-		vdbg_printk(FUJLAPTOP_DBG_TRACE,
-			    "auto-detecting disable_adjust\n");
-		disable_brightness_adjust = have_blnf ? 0 : 1;
+		if (ACPI_SUCCESS(acpi_get_handle(NULL,
+				"\\_SB.PCI0.LPCB.FJEX.SBL2", &handle)))
+			use_alt_lcd_levels = 1;
+		else
+			use_alt_lcd_levels = 0;
+		vdbg_printk(FUJLAPTOP_DBG_TRACE, "auto-detected usealt as "
+			"%i\n", use_alt_lcd_levels);
 	}
 }
 
@@ -768,19 +728,14 @@
 
 	/* do config (detect defaults) */
 	use_alt_lcd_levels = use_alt_lcd_levels == 1 ? 1 : 0;
-	disable_brightness_keys = disable_brightness_keys == 1 ? 1 : 0;
 	disable_brightness_adjust = disable_brightness_adjust == 1 ? 1 : 0;
 	vdbg_printk(FUJLAPTOP_DBG_INFO,
-		    "config: [alt interface: %d], [key disable: %d], [adjust disable: %d]\n",
-		    use_alt_lcd_levels, disable_brightness_keys,
-		    disable_brightness_adjust);
+		    "config: [alt interface: %d], [adjust disable: %d]\n",
+		    use_alt_lcd_levels, disable_brightness_adjust);
 
 	if (get_max_brightness() <= 0)
 		fujitsu->max_brightness = FUJITSU_LCD_N_LEVELS;
-	if (use_alt_lcd_levels)
-		get_lcd_level_alt();
-	else
-		get_lcd_level();
+	get_lcd_level();
 
 	return result;
 
@@ -831,43 +786,23 @@
 	case ACPI_FUJITSU_NOTIFY_CODE1:
 		keycode = 0;
 		oldb = fujitsu->brightness_level;
-		get_lcd_level();  /* the alt version always yields changed */
+		get_lcd_level();
 		newb = fujitsu->brightness_level;
 
 		vdbg_printk(FUJLAPTOP_DBG_TRACE,
 			    "brightness button event [%i -> %i (%i)]\n",
 			    oldb, newb, fujitsu->brightness_changed);
 
-		if (oldb == newb && fujitsu->brightness_changed) {
-			keycode = 0;
-			if (disable_brightness_keys != 1) {
-				if (oldb == 0) {
-					acpi_bus_generate_proc_event
-					    (fujitsu->dev,
-					     ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS,
-					     0);
-					keycode = KEY_BRIGHTNESSDOWN;
-				} else if (oldb ==
-					   (fujitsu->max_brightness) - 1) {
-					acpi_bus_generate_proc_event
-					    (fujitsu->dev,
-					     ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS,
-					     0);
-					keycode = KEY_BRIGHTNESSUP;
-				}
-			}
-		} else if (oldb < newb) {
+		if (oldb < newb) {
 			if (disable_brightness_adjust != 1) {
 				if (use_alt_lcd_levels)
 					set_lcd_level_alt(newb);
 				else
 					set_lcd_level(newb);
 			}
-			if (disable_brightness_keys != 1) {
-				acpi_bus_generate_proc_event(fujitsu->dev,
-					ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS, 0);
-				keycode = KEY_BRIGHTNESSUP;
-			}
+			acpi_bus_generate_proc_event(fujitsu->dev,
+				ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS, 0);
+			keycode = KEY_BRIGHTNESSUP;
 		} else if (oldb > newb) {
 			if (disable_brightness_adjust != 1) {
 				if (use_alt_lcd_levels)
@@ -875,13 +810,9 @@
 				else
 					set_lcd_level(newb);
 			}
-			if (disable_brightness_keys != 1) {
-				acpi_bus_generate_proc_event(fujitsu->dev,
-					ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS, 0);
-				keycode = KEY_BRIGHTNESSDOWN;
-			}
-		} else {
-			keycode = KEY_UNKNOWN;
+			acpi_bus_generate_proc_event(fujitsu->dev,
+				ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS, 0);
+			keycode = KEY_BRIGHTNESSDOWN;
 		}
 		break;
 	default:
@@ -1336,9 +1267,6 @@
 module_param(use_alt_lcd_levels, uint, 0644);
 MODULE_PARM_DESC(use_alt_lcd_levels,
 		 "Use alternative interface for lcd_levels (needed for Lifebook s6410).");
-module_param(disable_brightness_keys, uint, 0644);
-MODULE_PARM_DESC(disable_brightness_keys,
-		 "Disable brightness keys (eg. if they are already handled by the generic ACPI_VIDEO device).");
 module_param(disable_brightness_adjust, uint, 0644);
 MODULE_PARM_DESC(disable_brightness_adjust, "Disable brightness adjustment .");
 #ifdef CONFIG_FUJITSU_LAPTOP_DEBUG