[PATCH] Rewritten backlight infrastructure for portable Apple computers

This patch contains a total rewrite of the backlight infrastructure for
portable Apple computers.  Backward compatibility is retained.  A sysfs
interface allows userland to control the brightness with more steps than
before.  Userland is allowed to upload a brightness curve for different
monitors, similar to Mac OS X.

[akpm@osdl.org: add needed exports]
Signed-off-by: Michael Hanselmann <linux-kernel@hansmi.ch>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/powerpc/kernel/traps.c

@@ -32,6 +32,7 @@
 #include <linux/delay.h>
 #include <linux/kprobes.h>
 #include <linux/kexec.h>
+#include <linux/backlight.h>
 
 #include <asm/kdebug.h>
 #include <asm/pgtable.h>
@@ -105,10 +106,18 @@ int die(const char *str, struct pt_regs *regs, long err)
 	spin_lock_irq(&die_lock);
 	bust_spinlocks(1);
 #ifdef CONFIG_PMAC_BACKLIGHT
-	if (machine_is(powermac)) {
-		set_backlight_enable(1);
-		set_backlight_level(BACKLIGHT_MAX);
+	mutex_lock(&pmac_backlight_mutex);
+	if (machine_is(powermac) && pmac_backlight) {
+		struct backlight_properties *props;
+
+		down(&pmac_backlight->sem);
+		props = pmac_backlight->props;
+		props->brightness = props->max_brightness;
+		props->power = FB_BLANK_UNBLANK;
+		props->update_status(pmac_backlight);
+		up(&pmac_backlight->sem);
 	}
+	mutex_unlock(&pmac_backlight_mutex);
 #endif
 	printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
 #ifdef CONFIG_PREEMPT

arch/powerpc/platforms/powermac/backlight.c

@@ -3,200 +3,148 @@
  * Contains support for the backlight.
  *
  *   Copyright (C) 2000 Benjamin Herrenschmidt
+ *   Copyright (C) 2006 Michael Hanselmann <linux-kernel@hansmi.ch>
  *
  */
 
 #include <linux/config.h>
 #include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/stddef.h>
-#include <linux/reboot.h>
-#include <linux/nvram.h>
-#include <linux/console.h>
-#include <asm/sections.h>
-#include <asm/ptrace.h>
-#include <asm/io.h>
-#include <asm/pgtable.h>
-#include <asm/system.h>
+#include <linux/fb.h>
+#include <linux/backlight.h>
 #include <asm/prom.h>
-#include <asm/machdep.h>
-#include <asm/nvram.h>
 #include <asm/backlight.h>
 
-#include <linux/adb.h>
-#include <linux/pmu.h>
+#define OLD_BACKLIGHT_MAX 15
 
-static struct backlight_controller *backlighter;
-static void* backlighter_data;
-static int backlight_autosave;
-static int backlight_level = BACKLIGHT_MAX;
-static int backlight_enabled = 1;
-static int backlight_req_level = -1;
-static int backlight_req_enable = -1;
+/* Protect the pmac_backlight variable */
+DEFINE_MUTEX(pmac_backlight_mutex);
 
-static void backlight_callback(void *);
-static DECLARE_WORK(backlight_work, backlight_callback, NULL);
+/* Main backlight storage
+ *
+ * Backlight drivers in this variable are required to have the "props"
+ * attribute set and to have an update_status function.
+ *
+ * We can only store one backlight here, but since Apple laptops have only one
+ * internal display, it doesn't matter. Other backlight drivers can be used
+ * independently.
+ *
+ * Lock ordering:
+ * pmac_backlight_mutex (global, main backlight)
+ *   pmac_backlight->sem (backlight class)
+ */
+struct backlight_device *pmac_backlight;
 
-void register_backlight_controller(struct backlight_controller *ctrler,
-					  void *data, char *type)
+int pmac_has_backlight_type(const char *type)
 {
-	struct device_node* bk_node;
-	char *prop;
-	int valid = 0;
-
-	/* There's already a matching controller, bail out */
-	if (backlighter != NULL)
-		return;
-
-	bk_node = find_devices("backlight");
-
-#ifdef CONFIG_ADB_PMU
-	/* Special case for the old PowerBook since I can't test on it */
-	backlight_autosave = machine_is_compatible("AAPL,3400/2400")
-		|| machine_is_compatible("AAPL,3500");
-	if ((backlight_autosave
-	     || machine_is_compatible("AAPL,PowerBook1998")
-	     || machine_is_compatible("PowerBook1,1"))
-	    && !strcmp(type, "pmu"))
-		valid = 1;
-#endif
+	struct device_node* bk_node = find_devices("backlight");
+
 	if (bk_node) {
-		prop = get_property(bk_node, "backlight-control", NULL);
-		if (prop && !strncmp(prop, type, strlen(type)))
-			valid = 1;
-	}
-	if (!valid)
-		return;
-	backlighter = ctrler;
-	backlighter_data = data;
-
-	if (bk_node && !backlight_autosave)
-		prop = get_property(bk_node, "bklt", NULL);
-	else
-		prop = NULL;
-	if (prop) {
-		backlight_level = ((*prop)+1) >> 1;
-		if (backlight_level > BACKLIGHT_MAX)
-			backlight_level = BACKLIGHT_MAX;
+		char *prop = get_property(bk_node, "backlight-control", NULL);
+		if (prop && strncmp(prop, type, strlen(type)) == 0)
+			return 1;
 	}
 
-#ifdef CONFIG_ADB_PMU
-	if (backlight_autosave) {
-		struct adb_request req;
-		pmu_request(&req, NULL, 2, 0xd9, 0);
-		while (!req.complete)
-			pmu_poll();
-		backlight_level = req.reply[0] >> 4;
-	}
-#endif
-	acquire_console_sem();
-	if (!backlighter->set_enable(1, backlight_level, data))
-		backlight_enabled = 1;
-	release_console_sem();
-
-	printk(KERN_INFO "Registered \"%s\" backlight controller,"
-	       "level: %d/15\n", type, backlight_level);
+	return 0;
 }
-EXPORT_SYMBOL(register_backlight_controller);
 
-void unregister_backlight_controller(struct backlight_controller
-					    *ctrler, void *data)
+int pmac_backlight_curve_lookup(struct fb_info *info, int value)
 {
-	/* We keep the current backlight level (for now) */
-	if (ctrler == backlighter && data == backlighter_data)
-		backlighter = NULL;
+	int level = (FB_BACKLIGHT_LEVELS - 1);
+
+	if (info && info->bl_dev) {
+		int i, max = 0;
+
+		/* Look for biggest value */
+		for (i = 0; i < FB_BACKLIGHT_LEVELS; i++)
+			max = max((int)info->bl_curve[i], max);
+
+		/* Look for nearest value */
+		for (i = 0; i < FB_BACKLIGHT_LEVELS; i++) {
+			int diff = abs(info->bl_curve[i] - value);
+			if (diff < max) {
+				max = diff;
+				level = i;
+			}
+		}
+
+	}
+
+	return level;
 }
-EXPORT_SYMBOL(unregister_backlight_controller);
 
-static int __set_backlight_enable(int enable)
+static void pmac_backlight_key(int direction)
 {
-	int rc;
-
-	if (!backlighter)
-		return -ENODEV;
-	acquire_console_sem();
-	rc = backlighter->set_enable(enable, backlight_level,
-				     backlighter_data);
-	if (!rc)
-		backlight_enabled = enable;
-	release_console_sem();
-	return rc;
+	mutex_lock(&pmac_backlight_mutex);
+	if (pmac_backlight) {
+		struct backlight_properties *props;
+		int brightness;
+
+		down(&pmac_backlight->sem);
+		props = pmac_backlight->props;
+
+		brightness = props->brightness +
+			((direction?-1:1) * (props->max_brightness / 15));
+
+		if (brightness < 0)
+			brightness = 0;
+		else if (brightness > props->max_brightness)
+			brightness = props->max_brightness;
+
+		props->brightness = brightness;
+		props->update_status(pmac_backlight);
+
+		up(&pmac_backlight->sem);
+	}
+	mutex_unlock(&pmac_backlight_mutex);
 }
-int set_backlight_enable(int enable)
+
+void pmac_backlight_key_up()
 {
-	if (!backlighter)
-		return -ENODEV;
-	backlight_req_enable = enable;
-	schedule_work(&backlight_work);
-	return 0;
+	pmac_backlight_key(0);
 }
 
-EXPORT_SYMBOL(set_backlight_enable);
-
-int get_backlight_enable(void)
+void pmac_backlight_key_down()
 {
-	if (!backlighter)
-		return -ENODEV;
-	return backlight_enabled;
+	pmac_backlight_key(1);
 }
-EXPORT_SYMBOL(get_backlight_enable);
 
-static int __set_backlight_level(int level)
+int pmac_backlight_set_legacy_brightness(int brightness)
 {
-	int rc = 0;
-
-	if (!backlighter)
-		return -ENODEV;
-	if (level < BACKLIGHT_MIN)
-		level = BACKLIGHT_OFF;
-	if (level > BACKLIGHT_MAX)
-		level = BACKLIGHT_MAX;
-	acquire_console_sem();
-	if (backlight_enabled)
-		rc = backlighter->set_level(level, backlighter_data);
-	if (!rc)
-		backlight_level = level;
-	release_console_sem();
-	if (!rc && !backlight_autosave) {
-		level <<=1;
-		if (level & 0x10)
-			level |= 0x01;
-		// -- todo: save to property "bklt"
+	int error = -ENXIO;
+
+	mutex_lock(&pmac_backlight_mutex);
+	if (pmac_backlight) {
+		struct backlight_properties *props;
+
+		down(&pmac_backlight->sem);
+		props = pmac_backlight->props;
+		props->brightness = brightness *
+			props->max_brightness / OLD_BACKLIGHT_MAX;
+		props->update_status(pmac_backlight);
+		up(&pmac_backlight->sem);
+
+		error = 0;
 	}
-	return rc;
+	mutex_unlock(&pmac_backlight_mutex);
+
+	return error;
 }
-int set_backlight_level(int level)
+
+int pmac_backlight_get_legacy_brightness()
 {
-	if (!backlighter)
-		return -ENODEV;
-	backlight_req_level = level;
-	schedule_work(&backlight_work);
-	return 0;
-}
+	int result = -ENXIO;
 
-EXPORT_SYMBOL(set_backlight_level);
+	mutex_lock(&pmac_backlight_mutex);
+	if (pmac_backlight) {
+		struct backlight_properties *props;
 
-int get_backlight_level(void)
-{
-	if (!backlighter)
-		return -ENODEV;
-	return backlight_level;
-}
-EXPORT_SYMBOL(get_backlight_level);
+		down(&pmac_backlight->sem);
+		props = pmac_backlight->props;
+		result = props->brightness *
+			OLD_BACKLIGHT_MAX / props->max_brightness;
+		up(&pmac_backlight->sem);
+	}
+	mutex_unlock(&pmac_backlight_mutex);
 
-static void backlight_callback(void *dummy)
-{
-	int level, enable;
-
-	do {
-		level = backlight_req_level;
-		enable = backlight_req_enable;
-		mb();
-
-		if (level >= 0)
-			__set_backlight_level(level);
-		if (enable >= 0)
-			__set_backlight_enable(enable);
-	} while(cmpxchg(&backlight_req_level, level, -1) != level ||
-		cmpxchg(&backlight_req_enable, enable, -1) != enable);
+	return result;
 }

arch/powerpc/xmon/xmon.c

@@ -26,9 +26,6 @@
 #include <asm/prom.h>
 #include <asm/machdep.h>
 #include <asm/xmon.h>
-#ifdef CONFIG_PMAC_BACKLIGHT
-#include <asm/backlight.h>
-#endif
 #include <asm/processor.h>
 #include <asm/pgtable.h>
 #include <asm/mmu.h>

drivers/macintosh/Kconfig

@@ -99,17 +99,22 @@ config PMAC_MEDIABAY
 	  devices are not fully supported in the bay as I never had one to
 	  try with
 
-# made a separate option since backlight may end up beeing used
-# on non-powerbook machines (but only on PMU based ones AFAIK)
 config PMAC_BACKLIGHT
 	bool "Backlight control for LCD screens"
 	depends on ADB_PMU && (BROKEN || !PPC64)
 	help
-	  Say Y here to build in code to manage the LCD backlight on a
-	  Macintosh PowerBook.  With this code, the backlight will be turned
-	  on and off appropriately on power-management and lid-open/lid-closed
-	  events; also, the PowerBook button device will be enabled so you can
-	  change the screen brightness.
+	  Say Y here to enable Macintosh specific extensions of the generic
+	  backlight code. With this enabled, the brightness keys on older
+	  PowerBooks will be enabled so you can change the screen brightness.
+	  Newer models should use an userspace daemon like pbbuttonsd.
+
+config PMAC_BACKLIGHT_LEGACY
+	bool "Provide legacy ioctl's on /dev/pmu for the backlight"
+	depends on PMAC_BACKLIGHT && (BROKEN || !PPC64)
+	help
+	  Say Y if you want to enable legacy ioctl's on /dev/pmu. This is for
+	  programs which use this old interface. New and updated programs
+	  should use the backlight classes in sysfs.
 
 config ADB_MACIO
 	bool "Include MacIO (CHRP) ADB driver"

drivers/macintosh/Makefile

@@ -12,6 +12,7 @@ obj-$(CONFIG_INPUT_ADBHID)	+= adbhid.o
 obj-$(CONFIG_ANSLCD)		+= ans-lcd.o
 
 obj-$(CONFIG_ADB_PMU)		+= via-pmu.o
+obj-$(CONFIG_PMAC_BACKLIGHT)	+= via-pmu-backlight.o
 obj-$(CONFIG_ADB_CUDA)		+= via-cuda.o
 obj-$(CONFIG_PMAC_APM_EMU)	+= apm_emu.o
 obj-$(CONFIG_PMAC_SMU)		+= smu.o

drivers/macintosh/adbhid.c

@@ -503,9 +503,7 @@ adbhid_buttons_input(unsigned char *data, int nb, struct pt_regs *regs, int auto
 	case 0x1f: /* Powerbook button device */
 	  {
 		int down = (data[1] == (data[1] & 0xf));
-#ifdef CONFIG_PMAC_BACKLIGHT
-		int backlight = get_backlight_level();
-#endif
+
 		/*
 		 * XXX: Where is the contrast control for the passive?
 		 *  -- Cort
@@ -530,29 +528,17 @@ adbhid_buttons_input(unsigned char *data, int nb, struct pt_regs *regs, int auto
 
 		case 0xa:	/* brightness decrease */
 #ifdef CONFIG_PMAC_BACKLIGHT
-			if (!disable_kernel_backlight) {
-				if (down && backlight >= 0) {
-					if (backlight > BACKLIGHT_OFF)
-						set_backlight_level(backlight-1);
-					else
-						set_backlight_level(BACKLIGHT_OFF);
-				}
-			}
-#endif /* CONFIG_PMAC_BACKLIGHT */
+			if (!disable_kernel_backlight && down)
+				pmac_backlight_key_down();
+#endif
 			input_report_key(adbhid[id]->input, KEY_BRIGHTNESSDOWN, down);
 			break;
 
 		case 0x9:	/* brightness increase */
 #ifdef CONFIG_PMAC_BACKLIGHT
-			if (!disable_kernel_backlight) {
-				if (down && backlight >= 0) {
-					if (backlight < BACKLIGHT_MAX)
-						set_backlight_level(backlight+1);
-					else 
-						set_backlight_level(BACKLIGHT_MAX);
-				}
-			}
-#endif /* CONFIG_PMAC_BACKLIGHT */
+			if (!disable_kernel_backlight && down)
+				pmac_backlight_key_up();
+#endif
 			input_report_key(adbhid[id]->input, KEY_BRIGHTNESSUP, down);
 			break;
 

drivers/macintosh/via-pmu-backlight.c

+/*
+ * Backlight code for via-pmu
+ *
+ * Copyright (C) 1998 Paul Mackerras and Fabio Riccardi.
+ * Copyright (C) 2001-2002 Benjamin Herrenschmidt
+ * Copyright (C) 2006      Michael Hanselmann <linux-kernel@hansmi.ch>
+ *
+ */
+
+#include <asm/ptrace.h>
+#include <linux/adb.h>
+#include <linux/pmu.h>
+#include <asm/backlight.h>
+#include <asm/prom.h>
+
+#define MAX_PMU_LEVEL 0xFF
+
+static struct device_node *vias;
+static struct backlight_properties pmu_backlight_data;
+
+static int pmu_backlight_get_level_brightness(struct fb_info *info,
+		int level)
+{
+	int pmulevel;
+
+	/* Get and convert the value */
+	mutex_lock(&info->bl_mutex);
+	pmulevel = info->bl_curve[level] * FB_BACKLIGHT_MAX / MAX_PMU_LEVEL;
+	mutex_unlock(&info->bl_mutex);
+
+	if (pmulevel < 0)
+		pmulevel = 0;
+	else if (pmulevel > MAX_PMU_LEVEL)
+		pmulevel = MAX_PMU_LEVEL;
+
+	return pmulevel;
+}
+
+static int pmu_backlight_update_status(struct backlight_device *bd)
+{
+	struct fb_info *info = class_get_devdata(&bd->class_dev);
+	struct adb_request req;
+	int pmulevel, level = bd->props->brightness;
+
+	if (vias == NULL)
+		return -ENODEV;
+
+	if (bd->props->power != FB_BLANK_UNBLANK ||
+	    bd->props->fb_blank != FB_BLANK_UNBLANK)
+		level = 0;
+
+	pmulevel = pmu_backlight_get_level_brightness(info, level);
+
+	pmu_request(&req, NULL, 2, PMU_BACKLIGHT_BRIGHT, pmulevel);
+	pmu_wait_complete(&req);
+
+	pmu_request(&req, NULL, 2, PMU_POWER_CTRL,
+		PMU_POW_BACKLIGHT | (level > 0 ? PMU_POW_ON : PMU_POW_OFF));
+	pmu_wait_complete(&req);
+
+	return 0;
+}
+
+static int pmu_backlight_get_brightness(struct backlight_device *bd)
+{
+	return bd->props->brightness;
+}
+
+static struct backlight_properties pmu_backlight_data = {
+	.owner		= THIS_MODULE,
+	.get_brightness	= pmu_backlight_get_brightness,
+	.update_status	= pmu_backlight_update_status,
+	.max_brightness	= (FB_BACKLIGHT_LEVELS - 1),
+};
+
+void __init pmu_backlight_init(struct device_node *in_vias)
+{
+	struct backlight_device *bd;
+	struct fb_info *info;
+	char name[10];
+	int level, autosave;
+
+	vias = in_vias;
+
+	/* Special case for the old PowerBook since I can't test on it */
+	autosave =
+		machine_is_compatible("AAPL,3400/2400") ||
+		machine_is_compatible("AAPL,3500");
+
+	if (!autosave &&
+	    !pmac_has_backlight_type("pmu") &&
+	    !machine_is_compatible("AAPL,PowerBook1998") &&
+	    !machine_is_compatible("PowerBook1,1"))
+		return;
+
+	/* Actually, this is a hack, but I don't know of a better way
+	 * to get the first framebuffer device.
+	 */
+	info = registered_fb[0];
+	if (!info) {
+		printk("pmubl: No framebuffer found\n");
+		goto error;
+	}
+
+	snprintf(name, sizeof(name), "pmubl%d", info->node);
+
+	bd = backlight_device_register(name, info, &pmu_backlight_data);
+	if (IS_ERR(bd)) {
+		printk("pmubl: Backlight registration failed\n");
+		goto error;
+	}
+
+	mutex_lock(&info->bl_mutex);
+	info->bl_dev = bd;
+	fb_bl_default_curve(info, 0x7F, 0x46, 0x0E);
+	mutex_unlock(&info->bl_mutex);
+
+	level = pmu_backlight_data.max_brightness;
+
+	if (autosave) {
+		/* read autosaved value if available */
+		struct adb_request req;
+		pmu_request(&req, NULL, 2, 0xd9, 0);
+		pmu_wait_complete(&req);
+
+		mutex_lock(&info->bl_mutex);
+		level = pmac_backlight_curve_lookup(info,
+				(req.reply[0] >> 4) *
+				pmu_backlight_data.max_brightness / 15);
+		mutex_unlock(&info->bl_mutex);
+	}
+
+	up(&bd->sem);
+	bd->props->brightness = level;
+	bd->props->power = FB_BLANK_UNBLANK;
+	bd->props->update_status(bd);
+	down(&bd->sem);
+
+	mutex_lock(&pmac_backlight_mutex);
+	if (!pmac_backlight)
+		pmac_backlight = bd;
+	mutex_unlock(&pmac_backlight_mutex);
+
+	printk("pmubl: Backlight initialized (%s)\n", name);
+
+	return;
+
+error:
+	return;
+}

drivers/macintosh/via-pmu.c

@@ -144,7 +144,6 @@ static int data_index;
 static int data_len;
 static volatile int adb_int_pending;
 static volatile int disable_poll;
-static struct adb_request bright_req_1, bright_req_2;
 static struct device_node *vias;
 static int pmu_kind = PMU_UNKNOWN;
 static int pmu_fully_inited = 0;
@@ -161,7 +160,7 @@ static int drop_interrupts;
 #if defined(CONFIG_PM) && defined(CONFIG_PPC32)
 static int option_lid_wakeup = 1;
 #endif /* CONFIG_PM && CONFIG_PPC32 */
-#if (defined(CONFIG_PM)&&defined(CONFIG_PPC32))||defined(CONFIG_PMAC_BACKLIGHT)
+#if (defined(CONFIG_PM)&&defined(CONFIG_PPC32))||defined(CONFIG_PMAC_BACKLIGHT_LEGACY)
 static int sleep_in_progress;
 #endif
 static unsigned long async_req_locks;
@@ -208,10 +207,6 @@ static int proc_get_info(char *page, char **start, off_t off,
 			  int count, int *eof, void *data);
 static int proc_get_irqstats(char *page, char **start, off_t off,
 			  int count, int *eof, void *data);
-#ifdef CONFIG_PMAC_BACKLIGHT
-static int pmu_set_backlight_level(int level, void* data);
-static int pmu_set_backlight_enable(int on, int level, void* data);
-#endif /* CONFIG_PMAC_BACKLIGHT */
 static void pmu_pass_intr(unsigned char *data, int len);
 static int proc_get_batt(char *page, char **start, off_t off,
 			int count, int *eof, void *data);
@@ -292,13 +287,6 @@ static char *pbook_type[] = {
 	"Core99"
 };
 
-#ifdef CONFIG_PMAC_BACKLIGHT
-static struct backlight_controller pmu_backlight_controller = {
-	pmu_set_backlight_enable,
-	pmu_set_backlight_level
-};
-#endif /* CONFIG_PMAC_BACKLIGHT */
-
 int __init find_via_pmu(void)
 {
 	u64 taddr;
@@ -417,8 +405,6 @@ static int __init via_pmu_start(void)
 	if (vias == NULL)
 		return -ENODEV;
 
-	bright_req_1.complete = 1;
-	bright_req_2.complete = 1;
 	batt_req.complete = 1;
 
 #ifndef CONFIG_PPC_MERGE
@@ -483,9 +469,9 @@ static int __init via_pmu_dev_init(void)
 		return -ENODEV;
 
 #ifdef CONFIG_PMAC_BACKLIGHT
-	/* Enable backlight */
-	register_backlight_controller(&pmu_backlight_controller, NULL, "pmu");
-#endif /* CONFIG_PMAC_BACKLIGHT */
+	/* Initialize backlight */
+	pmu_backlight_init(vias);
+#endif
 
 #ifdef CONFIG_PPC32
   	if (machine_is_compatible("AAPL,3400/2400") ||
@@ -1424,7 +1410,7 @@ pmu_handle_data(unsigned char *data, int len, struct pt_regs *regs)
 #ifdef CONFIG_INPUT_ADBHID
 			if (!disable_kernel_backlight)
 #endif /* CONFIG_INPUT_ADBHID */
-				set_backlight_level(data[1] >> 4);
+				pmac_backlight_set_legacy_brightness(data[1] >> 4);
 #endif /* CONFIG_PMAC_BACKLIGHT */
 	}
 	/* Tick interrupt */
@@ -1674,61 +1660,6 @@ gpio1_interrupt(int irq, void *arg, struct pt_regs *regs)
 	return IRQ_NONE;
 }
 
-#ifdef CONFIG_PMAC_BACKLIGHT
-static int backlight_to_bright[] = {
-	0x7f, 0x46, 0x42, 0x3e, 0x3a, 0x36, 0x32, 0x2e,
-	0x2a, 0x26, 0x22, 0x1e, 0x1a, 0x16, 0x12, 0x0e
-};
- 
-static int
-pmu_set_backlight_enable(int on, int level, void* data)
-{
-	struct adb_request req;
-	
-	if (vias == NULL)
-		return -ENODEV;
-
-	if (on) {
-		pmu_request(&req, NULL, 2, PMU_BACKLIGHT_BRIGHT,
-			    backlight_to_bright[level]);
-		pmu_wait_complete(&req);
-	}
-	pmu_request(&req, NULL, 2, PMU_POWER_CTRL,
-		    PMU_POW_BACKLIGHT | (on ? PMU_POW_ON : PMU_POW_OFF));
-       	pmu_wait_complete(&req);
-
-	return 0;
-}
-
-static void
-pmu_bright_complete(struct adb_request *req)
-{
-	if (req == &bright_req_1)
-		clear_bit(1, &async_req_locks);
-	if (req == &bright_req_2)
-		clear_bit(2, &async_req_locks);
-}
-
-static int
-pmu_set_backlight_level(int level, void* data)
-{
-	if (vias == NULL)
-		return -ENODEV;
-
-	if (test_and_set_bit(1, &async_req_locks))
-		return -EAGAIN;
-	pmu_request(&bright_req_1, pmu_bright_complete, 2, PMU_BACKLIGHT_BRIGHT,
-		backlight_to_bright[level]);
-	if (test_and_set_bit(2, &async_req_locks))
-		return -EAGAIN;
-	pmu_request(&bright_req_2, pmu_bright_complete, 2, PMU_POWER_CTRL,
-		    PMU_POW_BACKLIGHT | (level > BACKLIGHT_OFF ?
-					 PMU_POW_ON : PMU_POW_OFF));
-
-	return 0;
-}
-#endif /* CONFIG_PMAC_BACKLIGHT */
-
 void
 pmu_enable_irled(int on)
 {
@@ -2145,9 +2076,8 @@ pmac_suspend_devices(void)
 		return -EBUSY;
 	}
 
-	/* Wait for completion of async backlight requests */
-	while (!bright_req_1.complete || !bright_req_2.complete ||
-			!batt_req.complete)
+	/* Wait for completion of async requests */
+	while (!batt_req.complete)
 		pmu_poll();
 
 	/* Giveup the lazy FPU & vec so we don't have to back them
@@ -2678,26 +2608,34 @@ pmu_ioctl(struct inode * inode, struct file *filp,
 			return put_user(1, argp);
 #endif /* CONFIG_PM && CONFIG_PPC32 */
 
-#ifdef CONFIG_PMAC_BACKLIGHT
-	/* Backlight should have its own device or go via
-	 * the fbdev
-	 */
+#ifdef CONFIG_PMAC_BACKLIGHT_LEGACY
+	/* Compatibility ioctl's for backlight */
 	case PMU_IOC_GET_BACKLIGHT:
+	{
+		int brightness;
+
 		if (sleep_in_progress)
 			return -EBUSY;
-		error = get_backlight_level();
-		if (error < 0)
-			return error;
-		return put_user(error, argp);
+
+		brightness = pmac_backlight_get_legacy_brightness();
+		if (brightness < 0)
+			return brightness;
+		else
+			return put_user(brightness, argp);
+
+	}
 	case PMU_IOC_SET_BACKLIGHT:
 	{
-		__u32 value;
+		int brightness;
+
 		if (sleep_in_progress)
 			return -EBUSY;
-		error = get_user(value, argp);
-		if (!error)
-			error = set_backlight_level(value);
-		break;
+
+		error = get_user(brightness, argp);
+		if (error)
+			return error;
+
+		return pmac_backlight_set_legacy_brightness(brightness);
 	}
 #ifdef CONFIG_INPUT_ADBHID
 	case PMU_IOC_GRAB_BACKLIGHT: {
@@ -2713,7 +2651,7 @@ pmu_ioctl(struct inode * inode, struct file *filp,
 		return 0;
 	}
 #endif /* CONFIG_INPUT_ADBHID */
-#endif /* CONFIG_PMAC_BACKLIGHT */
+#endif /* CONFIG_PMAC_BACKLIGHT_LEGACY */
 	case PMU_IOC_GET_MODEL:
 	    	return put_user(pmu_kind, argp);
 	case PMU_IOC_HAS_ADB:

drivers/video/Kconfig

@@ -86,6 +86,11 @@ config FB_FIRMWARE_EDID
 	 combination with certain motherboards and monitors are known to
 	 suffer from this problem.
 
+config FB_BACKLIGHT
+       bool
+       depends on FB
+       default n
+
 config FB_MODE_HELPERS
         bool "Enable Video Mode Handling Helpers"
         depends on FB
@@ -717,6 +722,16 @@ config FB_NVIDIA_I2C
 	  independently validate video mode parameters, you should say Y
 	  here.
 
+config FB_NVIDIA_BACKLIGHT
+	bool "Support for backlight control"
+	depends on FB_NVIDIA && PPC_PMAC
+	select FB_BACKLIGHT
+	select BACKLIGHT_LCD_SUPPORT
+	select BACKLIGHT_CLASS_DEVICE
+	default y
+	help
+	  Say Y here if you want to control the backlight of your display.
+
 config FB_RIVA
 	tristate "nVidia Riva support"
 	depends on FB && PCI
@@ -755,6 +770,16 @@ config FB_RIVA_DEBUG
 	  of debugging informations to provide to the maintainer when
 	  something goes wrong.
 
+config FB_RIVA_BACKLIGHT
+	bool "Support for backlight control"
+	depends on FB_RIVA && PPC_PMAC
+	select FB_BACKLIGHT
+	select BACKLIGHT_LCD_SUPPORT
+	select BACKLIGHT_CLASS_DEVICE
+	default y
+	help
+	  Say Y here if you want to control the backlight of your display.
+
 config FB_I810
 	tristate "Intel 810/815 support (EXPERIMENTAL)"
 	depends on FB && EXPERIMENTAL && PCI && X86_32
@@ -993,6 +1018,7 @@ config FB_RADEON
 
 	  There is a product page at
 	  http://apps.ati.com/ATIcompare/
+
 config FB_RADEON_I2C
 	bool "DDC/I2C for ATI Radeon support"
 	depends on FB_RADEON
@@ -1000,6 +1026,16 @@ config FB_RADEON_I2C
 	help
 	  Say Y here if you want DDC/I2C support for your Radeon board. 
 
+config FB_RADEON_BACKLIGHT
+	bool "Support for backlight control"
+	depends on FB_RADEON && PPC_PMAC
+	select FB_BACKLIGHT
+	select BACKLIGHT_LCD_SUPPORT
+	select BACKLIGHT_CLASS_DEVICE
+	default y
+	help
+	  Say Y here if you want to control the backlight of your display.
+
 config FB_RADEON_DEBUG
 	bool "Lots of debug output from Radeon driver"
 	depends on FB_RADEON
@@ -1024,6 +1060,16 @@ config FB_ATY128
 	  To compile this driver as a module, choose M here: the
 	  module will be called aty128fb.
 
+config FB_ATY128_BACKLIGHT
+	bool "Support for backlight control"
+	depends on FB_ATY128 && PPC_PMAC
+	select FB_BACKLIGHT
+	select BACKLIGHT_LCD_SUPPORT
+	select BACKLIGHT_CLASS_DEVICE
+	default y
+	help
+	  Say Y here if you want to control the backlight of your display.
+
 config FB_ATY
 	tristate "ATI Mach64 display support" if PCI || ATARI
 	depends on FB && !SPARC32
@@ -1066,6 +1112,16 @@ config FB_ATY_GX
 	  is at
 	  <http://support.ati.com/products/pc/mach64/graphics_xpression.html>.
 
+config FB_ATY_BACKLIGHT
+	bool "Support for backlight control"
+	depends on FB_ATY && PPC_PMAC
+	select FB_BACKLIGHT
+	select BACKLIGHT_LCD_SUPPORT
+	select BACKLIGHT_CLASS_DEVICE
+	default y
+	help
+	  Say Y here if you want to control the backlight of your display.
+
 config FB_S3TRIO
 	bool "S3 Trio display support"
 	depends on (FB = y) && PPC && BROKEN

drivers/video/aty/Makefile

@@ -10,5 +10,6 @@ atyfb-objs			:= $(atyfb-y)
 
 radeonfb-y			:= radeon_base.o radeon_pm.o radeon_monitor.o radeon_accel.o
 radeonfb-$(CONFIG_FB_RADEON_I2C)	+= radeon_i2c.o
+radeonfb-$(CONFIG_FB_RADEON_BACKLIGHT)	+= radeon_backlight.o
 radeonfb-objs			:= $(radeonfb-y)
 

drivers/video/aty/atyfb.h

@@ -151,6 +151,7 @@ struct atyfb_par {
 	int lock_blank;
 	unsigned long res_start;
 	unsigned long res_size;
+	struct pci_dev *pdev;
 #ifdef __sparc__
 	struct pci_mmap_map *mmap_map;
 	u8 mmaped;

drivers/video/aty/atyfb_base.c

@@ -66,6 +66,7 @@
 #include <linux/interrupt.h>
 #include <linux/spinlock.h>
 #include <linux/wait.h>
+#include <linux/backlight.h>
 
 #include <asm/io.h>
 #include <asm/uaccess.h>
@@ -2115,45 +2116,142 @@ static int atyfb_pci_resume(struct pci_dev *pdev)
 
 #endif /*  defined(CONFIG_PM) && defined(CONFIG_PCI) */
 
-#ifdef CONFIG_PMAC_BACKLIGHT
+/* Backlight */
+#ifdef CONFIG_FB_ATY_BACKLIGHT
+#define MAX_LEVEL 0xFF
 
-    /*
-     *   LCD backlight control
-     */
+static struct backlight_properties aty_bl_data;
 
-static int backlight_conv[] = {
-	0x00, 0x3f, 0x4c, 0x59, 0x66, 0x73, 0x80, 0x8d,
-	0x9a, 0xa7, 0xb4, 0xc1, 0xcf, 0xdc, 0xe9, 0xff
-};
+static int aty_bl_get_level_brightness(struct atyfb_par *par, int level)
+{
+	struct fb_info *info = pci_get_drvdata(par->pdev);
+	int atylevel;
+
+	/* Get and convert the value */
+	mutex_lock(&info->bl_mutex);
+	atylevel = info->bl_curve[level] * FB_BACKLIGHT_MAX / MAX_LEVEL;
+	mutex_unlock(&info->bl_mutex);
+
+	if (atylevel < 0)
+		atylevel = 0;
+	else if (atylevel > MAX_LEVEL)
+		atylevel = MAX_LEVEL;
 
-static int aty_set_backlight_enable(int on, int level, void *data)
+	return atylevel;
+}
+
+static int aty_bl_update_status(struct backlight_device *bd)
 {
-	struct fb_info *info = (struct fb_info *) data;
-	struct atyfb_par *par = (struct atyfb_par *) info->par;
+	struct atyfb_par *par = class_get_devdata(&bd->class_dev);
 	unsigned int reg = aty_ld_lcd(LCD_MISC_CNTL, par);
+	int level;
+
+	if (bd->props->power != FB_BLANK_UNBLANK ||
+	    bd->props->fb_blank != FB_BLANK_UNBLANK)
+		level = 0;
+	else
+		level = bd->props->brightness;
 
 	reg |= (BLMOD_EN | BIASMOD_EN);
-	if (on && level > BACKLIGHT_OFF) {
+	if (level > 0) {
 		reg &= ~BIAS_MOD_LEVEL_MASK;
-		reg |= (backlight_conv[level] << BIAS_MOD_LEVEL_SHIFT);
+		reg |= (aty_bl_get_level_brightness(par, level) << BIAS_MOD_LEVEL_SHIFT);
 	} else {
 		reg &= ~BIAS_MOD_LEVEL_MASK;
-		reg |= (backlight_conv[0] << BIAS_MOD_LEVEL_SHIFT);
+		reg |= (aty_bl_get_level_brightness(par, 0) << BIAS_MOD_LEVEL_SHIFT);
 	}
 	aty_st_lcd(LCD_MISC_CNTL, reg, par);
+
 	return 0;
 }
 
-static int aty_set_backlight_level(int level, void *data)
+static int aty_bl_get_brightness(struct backlight_device *bd)
 {
-	return aty_set_backlight_enable(1, level, data);
+	return bd->props->brightness;
 }
 
-static struct backlight_controller aty_backlight_controller = {
-	aty_set_backlight_enable,
-	aty_set_backlight_level
+static struct backlight_properties aty_bl_data = {
+	.owner	  = THIS_MODULE,
+	.get_brightness = aty_bl_get_brightness,
+	.update_status	= aty_bl_update_status,
+	.max_brightness = (FB_BACKLIGHT_LEVELS - 1),
 };
-#endif /* CONFIG_PMAC_BACKLIGHT */
+
+static void aty_bl_init(struct atyfb_par *par)
+{
+	struct fb_info *info = pci_get_drvdata(par->pdev);
+	struct backlight_device *bd;
+	char name[12];
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+	if (!pmac_has_backlight_type("ati"))
+		return;
+#endif
+
+	snprintf(name, sizeof(name), "atybl%d", info->node);
+
+	bd = backlight_device_register(name, par, &aty_bl_data);
+	if (IS_ERR(bd)) {
+		info->bl_dev = NULL;
+		printk("aty: Backlight registration failed\n");
+		goto error;
+	}
+
+	mutex_lock(&info->bl_mutex);
+	info->bl_dev = bd;
+	fb_bl_default_curve(info, 0,
+		0x3F * FB_BACKLIGHT_MAX / MAX_LEVEL,
+		0xFF * FB_BACKLIGHT_MAX / MAX_LEVEL);
+	mutex_unlock(&info->bl_mutex);
+
+	up(&bd->sem);
+	bd->props->brightness = aty_bl_data.max_brightness;
+	bd->props->power = FB_BLANK_UNBLANK;
+	bd->props->update_status(bd);
+	down(&bd->sem);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+	mutex_lock(&pmac_backlight_mutex);
+	if (!pmac_backlight)
+		pmac_backlight = bd;
+	mutex_unlock(&pmac_backlight_mutex);
+#endif
+
+	printk("aty: Backlight initialized (%s)\n", name);
+
+	return;
+
+error:
+	return;
+}
+
+static void aty_bl_exit(struct atyfb_par *par)
+{
+	struct fb_info *info = pci_get_drvdata(par->pdev);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+	mutex_lock(&pmac_backlight_mutex);
+#endif
+
+	mutex_lock(&info->bl_mutex);
+	if (info->bl_dev) {
+#ifdef CONFIG_PMAC_BACKLIGHT
+		if (pmac_backlight == info->bl_dev)
+			pmac_backlight = NULL;
+#endif
+
+		backlight_device_unregister(info->bl_dev);
+
+		printk("aty: Backlight unloaded\n");
+	}
+	mutex_unlock(&info->bl_mutex);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+	mutex_unlock(&pmac_backlight_mutex);
+#endif
+}
+
+#endif /* CONFIG_FB_ATY_BACKLIGHT */
 
 static void __init aty_calc_mem_refresh(struct atyfb_par *par, int xclk)
 {
@@ -2513,9 +2611,13 @@ static int __init aty_init(struct fb_info *info, const char *name)
 		/* these bits let the 101 powerbook wake up from sleep -- paulus */
 		aty_st_lcd(POWER_MANAGEMENT, aty_ld_lcd(POWER_MANAGEMENT, par)
 			   | (USE_F32KHZ | TRISTATE_MEM_EN), par);
-	} else if (M64_HAS(MOBIL_BUS))
-		register_backlight_controller(&aty_backlight_controller, info, "ati");
-#endif /* CONFIG_PMAC_BACKLIGHT */
+	} else
+#endif
+	if (M64_HAS(MOBIL_BUS)) {
+#ifdef CONFIG_FB_ATY_BACKLIGHT
+		aty_bl_init (par);
+#endif
+	}
 
 	memset(&var, 0, sizeof(var));
 #ifdef CONFIG_PPC
@@ -2674,8 +2776,16 @@ static int atyfb_blank(int blank, struct fb_info *info)
 		return 0;
 
 #ifdef CONFIG_PMAC_BACKLIGHT
-	if (machine_is(powermac) && blank > FB_BLANK_NORMAL)
-		set_backlight_enable(0);
+	if (machine_is(powermac) && blank > FB_BLANK_NORMAL) {
+		mutex_lock(&info->bl_mutex);
+		if (info->bl_dev) {
+			down(&info->bl_dev->sem);
+			info->bl_dev->props->power = FB_BLANK_POWERDOWN;
+			info->bl_dev->props->update_status(info->bl_dev);
+			up(&info->bl_dev->sem);
+		}
+		mutex_unlock(&info->bl_mutex);
+	}
 #elif defined(CONFIG_FB_ATY_GENERIC_LCD)
 	if (par->lcd_table && blank > FB_BLANK_NORMAL &&
 	    (aty_ld_lcd(LCD_GEN_CNTL, par) & LCD_ON)) {
@@ -2706,8 +2816,16 @@ static int atyfb_blank(int blank, struct fb_info *info)
 	aty_st_le32(CRTC_GEN_CNTL, gen_cntl, par);
 
 #ifdef CONFIG_PMAC_BACKLIGHT
-	if (machine_is(powermac) && blank <= FB_BLANK_NORMAL)
-		set_backlight_enable(1);
+	if (machine_is(powermac) && blank <= FB_BLANK_NORMAL) {
+		mutex_lock(&info->bl_mutex);
+		if (info->bl_dev) {
+			down(&info->bl_dev->sem);
+			info->bl_dev->props->power = FB_BLANK_UNBLANK;
+			info->bl_dev->props->update_status(info->bl_dev);
+			up(&info->bl_dev->sem);
+		}
+		mutex_unlock(&info->bl_mutex);
+	}
 #elif defined(CONFIG_FB_ATY_GENERIC_LCD)
 	if (par->lcd_table && blank <= FB_BLANK_NORMAL &&
 	    (aty_ld_lcd(LCD_GEN_CNTL, par) & LCD_ON)) {
@@ -3440,6 +3558,7 @@ static int __devinit atyfb_pci_probe(struct pci_dev *pdev, const struct pci_devi
 	par->res_start = res_start;
 	par->res_size = res_size;
 	par->irq = pdev->irq;
+	par->pdev = pdev;
 
 	/* Setup "info" structure */
 #ifdef __sparc__
@@ -3571,6 +3690,11 @@ static void __devexit atyfb_remove(struct fb_info *info)
 	aty_set_crtc(par, &saved_crtc);
 	par->pll_ops->set_pll(info, &saved_pll);
 
+#ifdef CONFIG_FB_ATY_BACKLIGHT
+	if (M64_HAS(MOBIL_BUS))
+		aty_bl_exit(par);
+#endif
+
 	unregister_framebuffer(info);
 
 #ifdef CONFIG_MTRR

drivers/video/aty/radeon_backlight.c

+/*
+ * Backlight code for ATI Radeon based graphic cards
+ *
+ * Copyright (c) 2000 Ani Joshi <ajoshi@kernel.crashing.org>
+ * Copyright (c) 2003 Benjamin Herrenschmidt <benh@kernel.crashing.org>
+ * Copyright (c) 2006 Michael Hanselmann <linux-kernel@hansmi.ch>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "radeonfb.h"
+#include <linux/backlight.h>
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+#include <asm/backlight.h>
+#endif
+
+#define MAX_RADEON_LEVEL 0xFF
+
+static struct backlight_properties radeon_bl_data;
+
+struct radeon_bl_privdata {
+	struct radeonfb_info *rinfo;
+	uint8_t negative;
+};
+
+static int radeon_bl_get_level_brightness(struct radeon_bl_privdata *pdata,
+		int level)
+{
+	struct fb_info *info = pdata->rinfo->info;
+	int rlevel;
+
+	mutex_lock(&info->bl_mutex);
+
+	/* Get and convert the value */
+	rlevel = pdata->rinfo->info->bl_curve[level] *
+		 FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL;
+
+	mutex_unlock(&info->bl_mutex);
+
+	if (pdata->negative)
+		rlevel = MAX_RADEON_LEVEL - rlevel;
+
+	if (rlevel < 0)
+		rlevel = 0;
+	else if (rlevel > MAX_RADEON_LEVEL)
+		rlevel = MAX_RADEON_LEVEL;
+
+	return rlevel;
+}
+
+static int radeon_bl_update_status(struct backlight_device *bd)
+{
+	struct radeon_bl_privdata *pdata = class_get_devdata(&bd->class_dev);
+	struct radeonfb_info *rinfo = pdata->rinfo;
+	u32 lvds_gen_cntl, tmpPixclksCntl;
+	int level;
+
+	if (rinfo->mon1_type != MT_LCD)
+		return 0;
+
+	/* We turn off the LCD completely instead of just dimming the
+	 * backlight. This provides some greater power saving and the display
+	 * is useless without backlight anyway.
+	 */
+        if (bd->props->power != FB_BLANK_UNBLANK ||
+	    bd->props->fb_blank != FB_BLANK_UNBLANK)
+		level = 0;
+	else
+		level = bd->props->brightness;
+
+	del_timer_sync(&rinfo->lvds_timer);
+	radeon_engine_idle();
+
+	lvds_gen_cntl = INREG(LVDS_GEN_CNTL);
+	if (level > 0) {
+		lvds_gen_cntl &= ~LVDS_DISPLAY_DIS;
+		if (!(lvds_gen_cntl & LVDS_BLON) || !(lvds_gen_cntl & LVDS_ON)) {
+			lvds_gen_cntl |= (rinfo->init_state.lvds_gen_cntl & LVDS_DIGON);
+			lvds_gen_cntl |= LVDS_BLON | LVDS_EN;
+			OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
+			lvds_gen_cntl &= ~LVDS_BL_MOD_LEVEL_MASK;
+			lvds_gen_cntl |=
+				(radeon_bl_get_level_brightness(pdata, level) <<
+				 LVDS_BL_MOD_LEVEL_SHIFT);
+			lvds_gen_cntl |= LVDS_ON;
+			lvds_gen_cntl |= (rinfo->init_state.lvds_gen_cntl & LVDS_BL_MOD_EN);
+			rinfo->pending_lvds_gen_cntl = lvds_gen_cntl;
+			mod_timer(&rinfo->lvds_timer,
+				  jiffies + msecs_to_jiffies(rinfo->panel_info.pwr_delay));
+		} else {
+			lvds_gen_cntl &= ~LVDS_BL_MOD_LEVEL_MASK;
+			lvds_gen_cntl |=
+				(radeon_bl_get_level_brightness(pdata, level) <<
+				 LVDS_BL_MOD_LEVEL_SHIFT);
+			OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
+		}
+		rinfo->init_state.lvds_gen_cntl &= ~LVDS_STATE_MASK;
+		rinfo->init_state.lvds_gen_cntl |= rinfo->pending_lvds_gen_cntl
+			& LVDS_STATE_MASK;
+	} else {
+		/* Asic bug, when turning off LVDS_ON, we have to make sure
+		   RADEON_PIXCLK_LVDS_ALWAYS_ON bit is off
+		*/
+		tmpPixclksCntl = INPLL(PIXCLKS_CNTL);
+		if (rinfo->is_mobility || rinfo->is_IGP)
+			OUTPLLP(PIXCLKS_CNTL, 0, ~PIXCLK_LVDS_ALWAYS_ONb);
+		lvds_gen_cntl &= ~(LVDS_BL_MOD_LEVEL_MASK | LVDS_BL_MOD_EN);
+		lvds_gen_cntl |= (radeon_bl_get_level_brightness(pdata, 0) <<
+				  LVDS_BL_MOD_LEVEL_SHIFT);
+		lvds_gen_cntl |= LVDS_DISPLAY_DIS;
+		OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
+		udelay(100);
+		lvds_gen_cntl &= ~(LVDS_ON | LVDS_EN);
+		OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
+		lvds_gen_cntl &= ~(LVDS_DIGON);
+		rinfo->pending_lvds_gen_cntl = lvds_gen_cntl;
+		mod_timer(&rinfo->lvds_timer,
+			  jiffies + msecs_to_jiffies(rinfo->panel_info.pwr_delay));
+		if (rinfo->is_mobility || rinfo->is_IGP)
+			OUTPLL(PIXCLKS_CNTL, tmpPixclksCntl);
+	}
+	rinfo->init_state.lvds_gen_cntl &= ~LVDS_STATE_MASK;
+	rinfo->init_state.lvds_gen_cntl |= (lvds_gen_cntl & LVDS_STATE_MASK);
+
+	return 0;
+}
+
+static int radeon_bl_get_brightness(struct backlight_device *bd)
+{
+	return bd->props->brightness;
+}
+
+static struct backlight_properties radeon_bl_data = {
+	.owner		= THIS_MODULE,
+	.get_brightness = radeon_bl_get_brightness,
+	.update_status	= radeon_bl_update_status,
+	.max_brightness = (FB_BACKLIGHT_LEVELS - 1),
+};
+
+void radeonfb_bl_init(struct radeonfb_info *rinfo)
+{
+	struct backlight_device *bd;
+	struct radeon_bl_privdata *pdata;
+	char name[12];
+
+	if (rinfo->mon1_type != MT_LCD)
+		return;
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+	if (!pmac_has_backlight_type("ati") &&
+	    !pmac_has_backlight_type("mnca"))
+		return;
+#endif
+
+	pdata = kmalloc(sizeof(struct radeon_bl_privdata), GFP_KERNEL);
+	if (!pdata) {
+		printk("radeonfb: Memory allocation failed\n");
+		goto error;
+	}
+
+	snprintf(name, sizeof(name), "radeonbl%d", rinfo->info->node);
+
+	bd = backlight_device_register(name, pdata, &radeon_bl_data);
+	if (IS_ERR(bd)) {
+		rinfo->info->bl_dev = NULL;
+		printk("radeonfb: Backlight registration failed\n");
+		goto error;
+	}
+
+	pdata->rinfo = rinfo;
+
+	/* Pardon me for that hack... maybe some day we can figure out in what
+	 * direction backlight should work on a given panel?
+	 */
+	pdata->negative =
+		(rinfo->family != CHIP_FAMILY_RV200 &&
+		 rinfo->family != CHIP_FAMILY_RV250 &&
+		 rinfo->family != CHIP_FAMILY_RV280 &&
+		 rinfo->family != CHIP_FAMILY_RV350);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+	pdata->negative = pdata->negative ||
+		machine_is_compatible("PowerBook4,3") ||
+		machine_is_compatible("PowerBook6,3") ||
+		machine_is_compatible("PowerBook6,5");
+#endif
+
+	mutex_lock(&rinfo->info->bl_mutex);
+	rinfo->info->bl_dev = bd;
+	fb_bl_default_curve(rinfo->info, 0,
+		 63 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL,
+		217 * FB_BACKLIGHT_MAX / MAX_RADEON_LEVEL);
+	mutex_unlock(&rinfo->info->bl_mutex);
+
+	up(&bd->sem);
+	bd->props->brightness = radeon_bl_data.max_brightness;
+	bd->props->power = FB_BLANK_UNBLANK;
+	bd->props->update_status(bd);
+	down(&bd->sem);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+	mutex_lock(&pmac_backlight_mutex);
+	if (!pmac_backlight)
+		pmac_backlight = bd;
+	mutex_unlock(&pmac_backlight_mutex);
+#endif
+
+	printk("radeonfb: Backlight initialized (%s)\n", name);
+
+	return;
+
+error:
+	kfree(pdata);
+	return;
+}
+
+void radeonfb_bl_exit(struct radeonfb_info *rinfo)
+{
+#ifdef CONFIG_PMAC_BACKLIGHT
+	mutex_lock(&pmac_backlight_mutex);
+#endif
+
+	mutex_lock(&rinfo->info->bl_mutex);
+	if (rinfo->info->bl_dev) {
+		struct radeon_bl_privdata *pdata;
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+		if (pmac_backlight == rinfo->info->bl_dev)
+			pmac_backlight = NULL;
+#endif
+
+		pdata = class_get_devdata(&rinfo->info->bl_dev->class_dev);
+		backlight_device_unregister(rinfo->info->bl_dev);
+		kfree(pdata);
+		rinfo->info->bl_dev = NULL;
+
+		printk("radeonfb: Backlight unloaded\n");
+	}
+	mutex_unlock(&rinfo->info->bl_mutex);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+	mutex_unlock(&pmac_backlight_mutex);
+#endif
+}

drivers/video/aty/radeon_base.c

@@ -78,10 +78,6 @@
 #include <asm/pci-bridge.h>
 #include "../macmodes.h"
 
-#ifdef CONFIG_PMAC_BACKLIGHT
-#include <asm/backlight.h>
-#endif
-
 #ifdef CONFIG_BOOTX_TEXT
 #include <asm/btext.h>
 #endif
@@ -277,20 +273,6 @@ static int nomtrr = 0;
  * prototypes
  */
 
-
-#ifdef CONFIG_PPC_OF
-
-#ifdef CONFIG_PMAC_BACKLIGHT
-static int radeon_set_backlight_enable(int on, int level, void *data);
-static int radeon_set_backlight_level(int level, void *data);
-static struct backlight_controller radeon_backlight_controller = {
-	radeon_set_backlight_enable,
-	radeon_set_backlight_level
-};
-#endif /* CONFIG_PMAC_BACKLIGHT */
-
-#endif /* CONFIG_PPC_OF */
-
 static void radeon_unmap_ROM(struct radeonfb_info *rinfo, struct pci_dev *dev)
 {
 	if (!rinfo->bios_seg)
@@ -1913,116 +1895,6 @@ static int __devinit radeon_set_fbinfo (struct radeonfb_info *rinfo)
         return 0;
 }
 
-
-#ifdef CONFIG_PMAC_BACKLIGHT
-
-/* TODO: Dbl check these tables, we don't go up to full ON backlight
- * in these, possibly because we noticed MacOS doesn't, but I'd prefer
- * having some more official numbers from ATI
- */
-static int backlight_conv_m6[] = {
-	0xff, 0xc0, 0xb5, 0xaa, 0x9f, 0x94, 0x89, 0x7e,
-	0x73, 0x68, 0x5d, 0x52, 0x47, 0x3c, 0x31, 0x24
-};
-static int backlight_conv_m7[] = {
-	0x00, 0x3f, 0x4a, 0x55, 0x60, 0x6b, 0x76, 0x81,
-	0x8c, 0x97, 0xa2, 0xad, 0xb8, 0xc3, 0xce, 0xd9
-};
-
-#define BACKLIGHT_LVDS_OFF
-#undef BACKLIGHT_DAC_OFF
-
-/* We turn off the LCD completely instead of just dimming the backlight.
- * This provides some greater power saving and the display is useless
- * without backlight anyway.
- */
-static int radeon_set_backlight_enable(int on, int level, void *data)
-{
-	struct radeonfb_info *rinfo = (struct radeonfb_info *)data;
-	u32 lvds_gen_cntl, tmpPixclksCntl;
-	int* conv_table;
-
-	if (rinfo->mon1_type != MT_LCD)
-		return 0;
-
-	/* Pardon me for that hack... maybe some day we can figure
-	 * out in what direction backlight should work on a given
-	 * panel ?
-	 */
-	if ((rinfo->family == CHIP_FAMILY_RV200 ||
-	     rinfo->family == CHIP_FAMILY_RV250 ||
-	     rinfo->family == CHIP_FAMILY_RV280 ||
-	     rinfo->family == CHIP_FAMILY_RV350) &&
-	    !machine_is_compatible("PowerBook4,3") &&
-	    !machine_is_compatible("PowerBook6,3") &&
-	    !machine_is_compatible("PowerBook6,5"))
-		conv_table = backlight_conv_m7;
-	else
-		conv_table = backlight_conv_m6;
-
-	del_timer_sync(&rinfo->lvds_timer);
-	radeon_engine_idle();
-
-	lvds_gen_cntl = INREG(LVDS_GEN_CNTL);
-	if (on && (level > BACKLIGHT_OFF)) {
-		lvds_gen_cntl &= ~LVDS_DISPLAY_DIS;
-		if (!(lvds_gen_cntl & LVDS_BLON) || !(lvds_gen_cntl & LVDS_ON)) {
-			lvds_gen_cntl |= (rinfo->init_state.lvds_gen_cntl & LVDS_DIGON);
-			lvds_gen_cntl |= LVDS_BLON | LVDS_EN;
-			OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
-			lvds_gen_cntl &= ~LVDS_BL_MOD_LEVEL_MASK;
-			lvds_gen_cntl |= (conv_table[level] <<
-					  LVDS_BL_MOD_LEVEL_SHIFT);
-			lvds_gen_cntl |= LVDS_ON;
-			lvds_gen_cntl |= (rinfo->init_state.lvds_gen_cntl & LVDS_BL_MOD_EN);
-			rinfo->pending_lvds_gen_cntl = lvds_gen_cntl;
-			mod_timer(&rinfo->lvds_timer,
-				  jiffies + msecs_to_jiffies(rinfo->panel_info.pwr_delay));
-		} else {
-			lvds_gen_cntl &= ~LVDS_BL_MOD_LEVEL_MASK;
-			lvds_gen_cntl |= (conv_table[level] <<
-					  LVDS_BL_MOD_LEVEL_SHIFT);
-			OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
-		}
-		rinfo->init_state.lvds_gen_cntl &= ~LVDS_STATE_MASK;
-		rinfo->init_state.lvds_gen_cntl |= rinfo->pending_lvds_gen_cntl
-			& LVDS_STATE_MASK;
-	} else {
-		/* Asic bug, when turning off LVDS_ON, we have to make sure
-		   RADEON_PIXCLK_LVDS_ALWAYS_ON bit is off
-		*/
-		tmpPixclksCntl = INPLL(PIXCLKS_CNTL);
-		if (rinfo->is_mobility || rinfo->is_IGP)
-			OUTPLLP(PIXCLKS_CNTL, 0, ~PIXCLK_LVDS_ALWAYS_ONb);
-		lvds_gen_cntl &= ~(LVDS_BL_MOD_LEVEL_MASK | LVDS_BL_MOD_EN);
-		lvds_gen_cntl |= (conv_table[0] <<
-				  LVDS_BL_MOD_LEVEL_SHIFT);
-		lvds_gen_cntl |= LVDS_DISPLAY_DIS;
-		OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
-		udelay(100);
-		lvds_gen_cntl &= ~(LVDS_ON | LVDS_EN);
-		OUTREG(LVDS_GEN_CNTL, lvds_gen_cntl);
-		lvds_gen_cntl &= ~(LVDS_DIGON);
-		rinfo->pending_lvds_gen_cntl = lvds_gen_cntl;
-		mod_timer(&rinfo->lvds_timer,
-			  jiffies + msecs_to_jiffies(rinfo->panel_info.pwr_delay));
-		if (rinfo->is_mobility || rinfo->is_IGP)
-			OUTPLL(PIXCLKS_CNTL, tmpPixclksCntl);
-	}
-	rinfo->init_state.lvds_gen_cntl &= ~LVDS_STATE_MASK;
-	rinfo->init_state.lvds_gen_cntl |= (lvds_gen_cntl & LVDS_STATE_MASK);
-
-	return 0;
-}
-
-
-static int radeon_set_backlight_level(int level, void *data)
-{
-	return radeon_set_backlight_enable(1, level, data);
-}
-#endif /* CONFIG_PMAC_BACKLIGHT */
-
-
 /*
  * This reconfigure the card's internal memory map. In theory, we'd like
  * to setup the card's memory at the same address as it's PCI bus address,
@@ -2477,14 +2349,7 @@ static int __devinit radeonfb_pci_register (struct pci_dev *pdev,
 						 MTRR_TYPE_WRCOMB, 1);
 #endif
 
-#ifdef CONFIG_PMAC_BACKLIGHT
-	if (rinfo->mon1_type == MT_LCD) {
-		register_backlight_controller(&radeon_backlight_controller,
-					      rinfo, "ati");
-		register_backlight_controller(&radeon_backlight_controller,
-					      rinfo, "mnca");
-	}
-#endif
+	radeonfb_bl_init(rinfo);
 
 	printk ("radeonfb (%s): %s\n", pci_name(rinfo->pdev), rinfo->name);
 
@@ -2528,7 +2393,8 @@ static void __devexit radeonfb_pci_unregister (struct pci_dev *pdev)
  
         if (!rinfo)
                 return;
- 
+
+	radeonfb_bl_exit(rinfo);
 	radeonfb_pm_exit(rinfo);
 
 	if (rinfo->mon1_EDID)

drivers/video/aty/radeonfb.h

@@ -625,4 +625,13 @@ extern int radeon_screen_blank(struct radeonfb_info *rinfo, int blank, int mode_
 extern void radeon_write_mode (struct radeonfb_info *rinfo, struct radeon_regs *mode,
 			       int reg_only);
 
+/* Backlight functions */
+#ifdef CONFIG_FB_RADEON_BACKLIGHT
+extern void radeonfb_bl_init(struct radeonfb_info *rinfo);
+extern void radeonfb_bl_exit(struct radeonfb_info *rinfo);
+#else
+static inline void radeonfb_bl_init(struct radeonfb_info *rinfo) {}
+static inline void radeonfb_bl_exit(struct radeonfb_info *rinfo) {}
+#endif
+
 #endif /* __RADEONFB_H__ */

drivers/video/chipsfb.c

@@ -148,9 +148,24 @@ static int chipsfb_set_par(struct fb_info *info)
 static int chipsfb_blank(int blank, struct fb_info *info)
 {
 #ifdef CONFIG_PMAC_BACKLIGHT
-	// used to disable backlight only for blank > 1, but it seems
-	// useful at blank = 1 too (saves battery, extends backlight life)
-	set_backlight_enable(!blank);
+	mutex_lock(&pmac_backlight_mutex);
+
+	if (pmac_backlight) {
+		down(&pmac_backlight->sem);
+
+		/* used to disable backlight only for blank > 1, but it seems
+		 * useful at blank = 1 too (saves battery, extends backlight
+		 * life)
+	 	 */
+		if (blank)
+			pmac_backlight->props->power = FB_BLANK_POWERDOWN;
+		else
+			pmac_backlight->props->power = FB_BLANK_UNBLANK;
+		pmac_backlight->props->update_status(pmac_backlight);
+		up(&pmac_backlight->sem);
+	}
+
+	mutex_unlock(&pmac_backlight_mutex);
 #endif /* CONFIG_PMAC_BACKLIGHT */
 
 	return 1;	/* get fb_blank to set the colormap to all black */
@@ -401,7 +416,14 @@ chipsfb_pci_init(struct pci_dev *dp, const struct pci_device_id *ent)
 
 #ifdef CONFIG_PMAC_BACKLIGHT
 	/* turn on the backlight */
-	set_backlight_enable(1);
+	mutex_lock(&pmac_backlight_mutex);
+	if (pmac_backlight) {
+		down(&pmac_backlight->sem);
+		pmac_backlight->props->power = FB_BLANK_UNBLANK;
+		pmac_backlight->props->update_status(pmac_backlight);
+		up(&pmac_backlight->sem);
+	}
+	mutex_unlock(&pmac_backlight_mutex);
 #endif /* CONFIG_PMAC_BACKLIGHT */
 
 #ifdef CONFIG_PPC

drivers/video/fbsysfs.c

@@ -18,6 +18,7 @@
 #include <linux/kernel.h>
 #include <linux/fb.h>
 #include <linux/console.h>
+#include <linux/module.h>
 
 /**
  * framebuffer_alloc - creates a new frame buffer info structure
@@ -55,6 +56,10 @@ struct fb_info *framebuffer_alloc(size_t size, struct device *dev)
 
 	info->device = dev;
 
+#ifdef CONFIG_FB_BACKLIGHT
+	mutex_init(&info->bl_mutex);
+#endif
+
 	return info;
 #undef PADDING
 #undef BYTES_PER_LONG
@@ -414,6 +419,65 @@ static ssize_t show_fbstate(struct class_device *class_device, char *buf)
 	return snprintf(buf, PAGE_SIZE, "%d\n", fb_info->state);
 }
 
+#ifdef CONFIG_FB_BACKLIGHT
+static ssize_t store_bl_curve(struct class_device *class_device,
+		const char *buf, size_t count)
+{
+	struct fb_info *fb_info = class_get_devdata(class_device);
+	u8 tmp_curve[FB_BACKLIGHT_LEVELS];
+	unsigned int i;
+
+	if (count != (FB_BACKLIGHT_LEVELS / 8 * 24))
+		return -EINVAL;
+
+	for (i = 0; i < (FB_BACKLIGHT_LEVELS / 8); ++i)
+		if (sscanf(&buf[i * 24],
+			"%2hhx %2hhx %2hhx %2hhx %2hhx %2hhx %2hhx %2hhx\n",
+			&tmp_curve[i * 8 + 0],
+			&tmp_curve[i * 8 + 1],
+			&tmp_curve[i * 8 + 2],
+			&tmp_curve[i * 8 + 3],
+			&tmp_curve[i * 8 + 4],
+			&tmp_curve[i * 8 + 5],
+			&tmp_curve[i * 8 + 6],
+			&tmp_curve[i * 8 + 7]) != 8)
+			return -EINVAL;
+
+	/* If there has been an error in the input data, we won't
+	 * reach this loop.
+	 */
+	mutex_lock(&fb_info->bl_mutex);
+	for (i = 0; i < FB_BACKLIGHT_LEVELS; ++i)
+		fb_info->bl_curve[i] = tmp_curve[i];
+	mutex_unlock(&fb_info->bl_mutex);
+
+	return count;
+}
+
+static ssize_t show_bl_curve(struct class_device *class_device, char *buf)
+{
+	struct fb_info *fb_info = class_get_devdata(class_device);
+	ssize_t len = 0;
+	unsigned int i;
+
+	mutex_lock(&fb_info->bl_mutex);
+	for (i = 0; i < FB_BACKLIGHT_LEVELS; i += 8)
+		len += snprintf(&buf[len], PAGE_SIZE,
+				"%02x %02x %02x %02x %02x %02x %02x %02x\n",
+				fb_info->bl_curve[i + 0],
+				fb_info->bl_curve[i + 1],
+				fb_info->bl_curve[i + 2],
+				fb_info->bl_curve[i + 3],
+				fb_info->bl_curve[i + 4],
+				fb_info->bl_curve[i + 5],
+				fb_info->bl_curve[i + 6],
+				fb_info->bl_curve[i + 7]);
+	mutex_unlock(&fb_info->bl_mutex);
+
+	return len;
+}
+#endif
+
 /* When cmap is added back in it should be a binary attribute
  * not a text one. Consideration should also be given to converting
  * fbdev to use configfs instead of sysfs */
@@ -432,6 +496,9 @@ static struct class_device_attribute class_device_attrs[] = {
 	__ATTR(con_rotate, S_IRUGO|S_IWUSR, show_con_rotate, store_con_rotate),
 	__ATTR(con_rotate_all, S_IWUSR, NULL, store_con_rotate_all),
 	__ATTR(state, S_IRUGO|S_IWUSR, show_fbstate, store_fbstate),
+#ifdef CONFIG_FB_BACKLIGHT
+	__ATTR(bl_curve, S_IRUGO|S_IWUSR, show_bl_curve, store_bl_curve),
+#endif
 };
 
 int fb_init_class_device(struct fb_info *fb_info)
@@ -454,4 +521,25 @@ void fb_cleanup_class_device(struct fb_info *fb_info)
 					 &class_device_attrs[i]);
 }
 
+#ifdef CONFIG_FB_BACKLIGHT
+/* This function generates a linear backlight curve
+ *
+ *     0: off
+ *   1-7: min
+ * 8-127: linear from min to max
+ */
+void fb_bl_default_curve(struct fb_info *fb_info, u8 off, u8 min, u8 max)
+{
+	unsigned int i, flat, count, range = (max - min);
+
+	fb_info->bl_curve[0] = off;
 
+	for (flat = 1; flat < (FB_BACKLIGHT_LEVELS / 16); ++flat)
+		fb_info->bl_curve[flat] = min;
+
+	count = FB_BACKLIGHT_LEVELS * 15 / 16;
+	for (i = 0; i < count; ++i)
+		fb_info->bl_curve[flat + i] = min + (range * (i + 1) / count);
+}
+EXPORT_SYMBOL_GPL(fb_bl_default_curve);
+#endif

drivers/video/nvidia/Makefile

@@ -7,6 +7,7 @@ obj-$(CONFIG_FB_NVIDIA)          += nvidiafb.o
 nvidiafb-y                       := nvidia.o nv_hw.o nv_setup.o \
 			            nv_accel.o
 nvidiafb-$(CONFIG_FB_NVIDIA_I2C) += nv_i2c.o
+nvidiafb-$(CONFIG_FB_NVIDIA_BACKLIGHT)  += nv_backlight.o
 nvidiafb-$(CONFIG_PPC_OF)	 += nv_of.o
 
-nvidiafb-objs                    := $(nvidiafb-y)
\ No newline at end of file
+nvidiafb-objs                    := $(nvidiafb-y)

drivers/video/nvidia/nv_backlight.c

+/*
+ * Backlight code for nVidia based graphic cards
+ *
+ * Copyright 2004 Antonino Daplas <adaplas@pol.net>
+ * Copyright (c) 2006 Michael Hanselmann <linux-kernel@hansmi.ch>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/backlight.h>
+#include <linux/fb.h>
+#include <linux/pci.h>
+#include "nv_local.h"
+#include "nv_type.h"
+#include "nv_proto.h"
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+#include <asm/backlight.h>
+#include <asm/machdep.h>
+#endif
+
+/* We do not have any information about which values are allowed, thus
+ * we used safe values.
+ */
+#define MIN_LEVEL 0x158
+#define MAX_LEVEL 0x534
+
+static struct backlight_properties nvidia_bl_data;
+
+static int nvidia_bl_get_level_brightness(struct nvidia_par *par,
+		int level)
+{
+	struct fb_info *info = pci_get_drvdata(par->pci_dev);
+	int nlevel;
+
+	/* Get and convert the value */
+	mutex_lock(&info->bl_mutex);
+	nlevel = info->bl_curve[level] * FB_BACKLIGHT_MAX / MAX_LEVEL;
+	mutex_unlock(&info->bl_mutex);
+
+	if (nlevel < 0)
+		nlevel = 0;
+	else if (nlevel < MIN_LEVEL)
+		nlevel = MIN_LEVEL;
+	else if (nlevel > MAX_LEVEL)
+		nlevel = MAX_LEVEL;
+
+	return nlevel;
+}
+
+static int nvidia_bl_update_status(struct backlight_device *bd)
+{
+	struct nvidia_par *par = class_get_devdata(&bd->class_dev);
+	u32 tmp_pcrt, tmp_pmc, fpcontrol;
+	int level;
+
+	if (!par->FlatPanel)
+		return 0;
+
+	if (bd->props->power != FB_BLANK_UNBLANK ||
+	    bd->props->fb_blank != FB_BLANK_UNBLANK)
+		level = 0;
+	else
+		level = bd->props->brightness;
+
+	tmp_pmc = NV_RD32(par->PMC, 0x10F0) & 0x0000FFFF;
+	tmp_pcrt = NV_RD32(par->PCRTC0, 0x081C) & 0xFFFFFFFC;
+	fpcontrol = NV_RD32(par->PRAMDAC, 0x0848) & 0xCFFFFFCC;
+
+	if (level > 0) {
+		tmp_pcrt |= 0x1;
+		tmp_pmc |= (1 << 31); /* backlight bit */
+		tmp_pmc |= nvidia_bl_get_level_brightness(par, level) << 16;
+		fpcontrol |= par->fpSyncs;
+	} else
+		fpcontrol |= 0x20000022;
+
+	NV_WR32(par->PCRTC0, 0x081C, tmp_pcrt);
+	NV_WR32(par->PMC, 0x10F0, tmp_pmc);
+	NV_WR32(par->PRAMDAC, 0x848, fpcontrol);
+
+	return 0;
+}
+
+static int nvidia_bl_get_brightness(struct backlight_device *bd)
+{
+	return bd->props->brightness;
+}
+
+static struct backlight_properties nvidia_bl_data = {
+	.owner		= THIS_MODULE,
+	.get_brightness = nvidia_bl_get_brightness,
+	.update_status	= nvidia_bl_update_status,
+	.max_brightness = (FB_BACKLIGHT_LEVELS - 1),
+};
+
+void nvidia_bl_init(struct nvidia_par *par)
+{
+	struct fb_info *info = pci_get_drvdata(par->pci_dev);
+	struct backlight_device *bd;
+	char name[12];
+
+	if (!par->FlatPanel)
+		return;
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+	if (!machine_is(powermac) ||
+	    !pmac_has_backlight_type("mnca"))
+		return;
+#endif
+
+	snprintf(name, sizeof(name), "nvidiabl%d", info->node);
+
+	bd = backlight_device_register(name, par, &nvidia_bl_data);
+	if (IS_ERR(bd)) {
+		info->bl_dev = NULL;
+		printk("nvidia: Backlight registration failed\n");
+		goto error;
+	}
+
+	mutex_lock(&info->bl_mutex);
+	info->bl_dev = bd;
+	fb_bl_default_curve(info, 0,
+		0x158 * FB_BACKLIGHT_MAX / MAX_LEVEL,
+		0x534 * FB_BACKLIGHT_MAX / MAX_LEVEL);
+	mutex_unlock(&info->bl_mutex);
+
+	up(&bd->sem);
+	bd->props->brightness = nvidia_bl_data.max_brightness;
+	bd->props->power = FB_BLANK_UNBLANK;
+	bd->props->update_status(bd);
+	down(&bd->sem);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+	mutex_lock(&pmac_backlight_mutex);
+	if (!pmac_backlight)
+		pmac_backlight = bd;
+	mutex_unlock(&pmac_backlight_mutex);
+#endif
+
+	printk("nvidia: Backlight initialized (%s)\n", name);
+
+	return;
+
+error:
+	return;
+}
+
+void nvidia_bl_exit(struct nvidia_par *par)
+{
+	struct fb_info *info = pci_get_drvdata(par->pci_dev);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+	mutex_lock(&pmac_backlight_mutex);
+#endif
+
+	mutex_lock(&info->bl_mutex);
+	if (info->bl_dev) {
+#ifdef CONFIG_PMAC_BACKLIGHT
+		if (pmac_backlight == info->bl_dev)
+			pmac_backlight = NULL;
+#endif
+
+		backlight_device_unregister(info->bl_dev);
+
+		printk("nvidia: Backlight unloaded\n");
+	}
+	mutex_unlock(&info->bl_mutex);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+	mutex_unlock(&pmac_backlight_mutex);
+#endif
+}

drivers/video/nvidia/nv_proto.h

@@ -63,4 +63,14 @@ extern void nvidiafb_imageblit(struct fb_info *info,
 			       const struct fb_image *image);
 extern int nvidiafb_sync(struct fb_info *info);
 extern u8 byte_rev[256];
+
+/* in nv_backlight.h */
+#ifdef CONFIG_FB_NVIDIA_BACKLIGHT
+extern void nvidia_bl_init(struct nvidia_par *par);
+extern void nvidia_bl_exit(struct nvidia_par *par);
+#else
+static inline void nvidia_bl_init(struct nvidia_par *par) {}
+static inline void nvidia_bl_exit(struct nvidia_par *par) {}
+#endif
+
 #endif				/* __NV_PROTO_H__ */

drivers/video/nvidia/nvidia.c

@@ -22,6 +22,7 @@
 #include <linux/init.h>
 #include <linux/pci.h>
 #include <linux/console.h>
+#include <linux/backlight.h>
 #ifdef CONFIG_MTRR
 #include <asm/mtrr.h>
 #endif
@@ -29,10 +30,6 @@
 #include <asm/prom.h>
 #include <asm/pci-bridge.h>
 #endif
-#ifdef CONFIG_PMAC_BACKLIGHT
-#include <asm/machdep.h>
-#include <asm/backlight.h>
-#endif
 
 #include "nv_local.h"
 #include "nv_type.h"
@@ -470,75 +467,6 @@ static struct fb_var_screeninfo __devinitdata nvidiafb_default_var = {
 	.vmode = FB_VMODE_NONINTERLACED
 };
 
-/*
- * Backlight control
- */
-#ifdef CONFIG_PMAC_BACKLIGHT
-
-static int nvidia_backlight_levels[] = {
-	0x158,
-	0x192,
-	0x1c6,
-	0x200,
-	0x234,
-	0x268,
-	0x2a2,
-	0x2d6,
-	0x310,
-	0x344,
-	0x378,
-	0x3b2,
-	0x3e6,
-	0x41a,
-	0x454,
-	0x534,
-};
-
-/* ------------------------------------------------------------------------- *
- *
- * Backlight operations
- *
- * ------------------------------------------------------------------------- */
-
-static int nvidia_set_backlight_enable(int on, int level, void *data)
-{
-	struct nvidia_par *par = data;
-	u32 tmp_pcrt, tmp_pmc, fpcontrol;
-
-	tmp_pmc = NV_RD32(par->PMC, 0x10F0) & 0x0000FFFF;
-	tmp_pcrt = NV_RD32(par->PCRTC0, 0x081C) & 0xFFFFFFFC;
-	fpcontrol = NV_RD32(par->PRAMDAC, 0x0848) & 0xCFFFFFCC;
-
-	if (on && (level > BACKLIGHT_OFF)) {
-		tmp_pcrt |= 0x1;
-		tmp_pmc |= (1 << 31);	// backlight bit
-		tmp_pmc |= nvidia_backlight_levels[level - 1] << 16;
-	}
-
-	if (on)
-		fpcontrol |= par->fpSyncs;
-	else
-		fpcontrol |= 0x20000022;
-
-	NV_WR32(par->PCRTC0, 0x081C, tmp_pcrt);
-	NV_WR32(par->PMC, 0x10F0, tmp_pmc);
-	NV_WR32(par->PRAMDAC, 0x848, fpcontrol);
-
-	return 0;
-}
-
-static int nvidia_set_backlight_level(int level, void *data)
-{
-	return nvidia_set_backlight_enable(1, level, data);
-}
-
-static struct backlight_controller nvidia_backlight_controller = {
-	nvidia_set_backlight_enable,
-	nvidia_set_backlight_level
-};
-
-#endif				/* CONFIG_PMAC_BACKLIGHT */
-
 static void nvidiafb_load_cursor_image(struct nvidia_par *par, u8 * data8,
 				       u16 bg, u16 fg, u32 w, u32 h)
 {
@@ -1355,10 +1283,15 @@ static int nvidiafb_blank(int blank, struct fb_info *info)
 	NVWriteSeq(par, 0x01, tmp);
 	NVWriteCrtc(par, 0x1a, vesa);
 
-#ifdef CONFIG_PMAC_BACKLIGHT
-	if (par->FlatPanel && machine_is(powermac)) {
-		set_backlight_enable(!blank);
+#ifdef CONFIG_FB_NVIDIA_BACKLIGHT
+	mutex_lock(&info->bl_mutex);
+	if (info->bl_dev) {
+		down(&info->bl_dev->sem);
+		info->bl_dev->props->power = blank;
+		info->bl_dev->props->update_status(info->bl_dev);
+		up(&info->bl_dev->sem);
 	}
+	mutex_unlock(&info->bl_mutex);
 #endif
 
 	NVTRACE_LEAVE();
@@ -1741,11 +1674,9 @@ static int __devinit nvidiafb_probe(struct pci_dev *pd,
 	       "PCI nVidia %s framebuffer (%dMB @ 0x%lX)\n",
 	       info->fix.id,
 	       par->FbMapSize / (1024 * 1024), info->fix.smem_start);
-#ifdef CONFIG_PMAC_BACKLIGHT
-	if (par->FlatPanel && machine_is(powermac))
-		register_backlight_controller(&nvidia_backlight_controller,
-					      par, "mnca");
-#endif
+
+	nvidia_bl_init(par);
+
 	NVTRACE_LEAVE();
 	return 0;
 
@@ -1775,6 +1706,8 @@ static void __exit nvidiafb_remove(struct pci_dev *pd)
 
 	NVTRACE_ENTER();
 
+	nvidia_bl_exit(par);
+
 	unregister_framebuffer(info);
 #ifdef CONFIG_MTRR
 	if (par->mtrr.vram_valid)

drivers/video/riva/fbdev.c

@@ -41,6 +41,7 @@
 #include <linux/fb.h>
 #include <linux/init.h>
 #include <linux/pci.h>
+#include <linux/backlight.h>
 #ifdef CONFIG_MTRR
 #include <asm/mtrr.h>
 #endif
@@ -272,34 +273,154 @@ static const struct riva_regs reg_template = {
 /*
  * Backlight control
  */
-#ifdef CONFIG_PMAC_BACKLIGHT
+#ifdef CONFIG_FB_RIVA_BACKLIGHT
+/* We do not have any information about which values are allowed, thus
+ * we used safe values.
+ */
+#define MIN_LEVEL 0x158
+#define MAX_LEVEL 0x534
 
-static int riva_backlight_levels[] = {
-    0x158,
-    0x192,
-    0x1c6,
-    0x200,
-    0x234,
-    0x268,
-    0x2a2,
-    0x2d6,
-    0x310,
-    0x344,
-    0x378,
-    0x3b2,
-    0x3e6,
-    0x41a,
-    0x454,
-    0x534,
-};
+static struct backlight_properties riva_bl_data;
+
+static int riva_bl_get_level_brightness(struct riva_par *par,
+		int level)
+{
+	struct fb_info *info = pci_get_drvdata(par->pdev);
+	int nlevel;
+
+	/* Get and convert the value */
+	mutex_lock(&info->bl_mutex);
+	nlevel = info->bl_curve[level] * FB_BACKLIGHT_MAX / MAX_LEVEL;
+	mutex_unlock(&info->bl_mutex);
+
+	if (nlevel < 0)
+		nlevel = 0;
+	else if (nlevel < MIN_LEVEL)
+		nlevel = MIN_LEVEL;
+	else if (nlevel > MAX_LEVEL)
+		nlevel = MAX_LEVEL;
+
+	return nlevel;
+}
+
+static int riva_bl_update_status(struct backlight_device *bd)
+{
+	struct riva_par *par = class_get_devdata(&bd->class_dev);
+	U032 tmp_pcrt, tmp_pmc;
+	int level;
+
+	if (bd->props->power != FB_BLANK_UNBLANK ||
+	    bd->props->fb_blank != FB_BLANK_UNBLANK)
+		level = 0;
+	else
+		level = bd->props->brightness;
+
+	tmp_pmc = par->riva.PMC[0x10F0/4] & 0x0000FFFF;
+	tmp_pcrt = par->riva.PCRTC0[0x081C/4] & 0xFFFFFFFC;
+	if(level > 0) {
+		tmp_pcrt |= 0x1;
+		tmp_pmc |= (1 << 31); /* backlight bit */
+		tmp_pmc |= riva_bl_get_level_brightness(par, level) << 16; /* level */
+	}
+	par->riva.PCRTC0[0x081C/4] = tmp_pcrt;
+	par->riva.PMC[0x10F0/4] = tmp_pmc;
+
+	return 0;
+}
+
+static int riva_bl_get_brightness(struct backlight_device *bd)
+{
+	return bd->props->brightness;
+}
 
-static int riva_set_backlight_enable(int on, int level, void *data);
-static int riva_set_backlight_level(int level, void *data);
-static struct backlight_controller riva_backlight_controller = {
-	riva_set_backlight_enable,
-	riva_set_backlight_level
+static struct backlight_properties riva_bl_data = {
+	.owner    = THIS_MODULE,
+	.get_brightness = riva_bl_get_brightness,
+	.update_status	= riva_bl_update_status,
+	.max_brightness = (FB_BACKLIGHT_LEVELS - 1),
 };
-#endif /* CONFIG_PMAC_BACKLIGHT */
+
+static void riva_bl_init(struct riva_par *par)
+{
+	struct fb_info *info = pci_get_drvdata(par->pdev);
+	struct backlight_device *bd;
+	char name[12];
+
+	if (!par->FlatPanel)
+		return;
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+	if (!machine_is(powermac) ||
+	    !pmac_has_backlight_type("mnca"))
+		return;
+#endif
+
+	snprintf(name, sizeof(name), "rivabl%d", info->node);
+
+	bd = backlight_device_register(name, par, &riva_bl_data);
+	if (IS_ERR(bd)) {
+		info->bl_dev = NULL;
+		printk("riva: Backlight registration failed\n");
+		goto error;
+	}
+
+	mutex_lock(&info->bl_mutex);
+	info->bl_dev = bd;
+	fb_bl_default_curve(info, 0,
+		0x158 * FB_BACKLIGHT_MAX / MAX_LEVEL,
+		0x534 * FB_BACKLIGHT_MAX / MAX_LEVEL);
+	mutex_unlock(&info->bl_mutex);
+
+	up(&bd->sem);
+	bd->props->brightness = riva_bl_data.max_brightness;
+	bd->props->power = FB_BLANK_UNBLANK;
+	bd->props->update_status(bd);
+	down(&bd->sem);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+	mutex_lock(&pmac_backlight_mutex);
+	if (!pmac_backlight)
+		pmac_backlight = bd;
+	mutex_unlock(&pmac_backlight_mutex);
+#endif
+
+	printk("riva: Backlight initialized (%s)\n", name);
+
+	return;
+
+error:
+	return;
+}
+
+static void riva_bl_exit(struct riva_par *par)
+{
+	struct fb_info *info = pci_get_drvdata(par->pdev);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+	mutex_lock(&pmac_backlight_mutex);
+#endif
+
+	mutex_lock(&info->bl_mutex);
+	if (info->bl_dev) {
+#ifdef CONFIG_PMAC_BACKLIGHT
+		if (pmac_backlight == info->bl_dev)
+			pmac_backlight = NULL;
+#endif
+
+		backlight_device_unregister(info->bl_dev);
+
+		printk("riva: Backlight unloaded\n");
+	}
+	mutex_unlock(&info->bl_mutex);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+	mutex_unlock(&pmac_backlight_mutex);
+#endif
+}
+#else
+static inline void riva_bl_init(struct riva_par *par) {}
+static inline void riva_bl_exit(struct riva_par *par) {}
+#endif /* CONFIG_FB_RIVA_BACKLIGHT */
 
 /* ------------------------------------------------------------------------- *
  *
@@ -971,36 +1092,6 @@ static int riva_get_cmap_len(const struct fb_var_screeninfo *var)
 	return rc;
 }
 
-/* ------------------------------------------------------------------------- *
- *
- * Backlight operations
- *
- * ------------------------------------------------------------------------- */
-
-#ifdef CONFIG_PMAC_BACKLIGHT
-static int riva_set_backlight_enable(int on, int level, void *data)
-{
-	struct riva_par *par = data;
-	U032 tmp_pcrt, tmp_pmc;
-
-	tmp_pmc = par->riva.PMC[0x10F0/4] & 0x0000FFFF;
-	tmp_pcrt = par->riva.PCRTC0[0x081C/4] & 0xFFFFFFFC;
-	if(on && (level > BACKLIGHT_OFF)) {
-		tmp_pcrt |= 0x1;
-		tmp_pmc |= (1 << 31); // backlight bit
-		tmp_pmc |= riva_backlight_levels[level-1] << 16; // level
-	}
-	par->riva.PCRTC0[0x081C/4] = tmp_pcrt;
-	par->riva.PMC[0x10F0/4] = tmp_pmc;
-	return 0;
-}
-
-static int riva_set_backlight_level(int level, void *data)
-{
-	return riva_set_backlight_enable(1, level, data);
-}
-#endif /* CONFIG_PMAC_BACKLIGHT */
-
 /* ------------------------------------------------------------------------- *
  *
  * framebuffer operations
@@ -1247,10 +1338,15 @@ static int rivafb_blank(int blank, struct fb_info *info)
 	SEQout(par, 0x01, tmp);
 	CRTCout(par, 0x1a, vesa);
 
-#ifdef CONFIG_PMAC_BACKLIGHT
-	if ( par->FlatPanel && machine_is(powermac)) {
-		set_backlight_enable(!blank);
+#ifdef CONFIG_FB_RIVA_BACKLIGHT
+	mutex_lock(&info->bl_mutex);
+	if (info->bl_dev) {
+		down(&info->bl_dev->sem);
+		info->bl_dev->props->power = blank;
+		info->bl_dev->props->update_status(info->bl_dev);
+		up(&info->bl_dev->sem);
 	}
+	mutex_unlock(&info->bl_mutex);
 #endif
 
 	NVTRACE_LEAVE();
@@ -2037,11 +2133,9 @@ static int __devinit rivafb_probe(struct pci_dev *pd,
 		RIVAFB_VERSION,
 		info->fix.smem_len / (1024 * 1024),
 		info->fix.smem_start);
-#ifdef CONFIG_PMAC_BACKLIGHT
-	if (default_par->FlatPanel && machine_is(powermac))
-		register_backlight_controller(&riva_backlight_controller,
-					      default_par, "mnca");
-#endif
+
+	riva_bl_init(info->par);
+
 	NVTRACE_LEAVE();
 	return 0;
 
@@ -2074,6 +2168,8 @@ static void __exit rivafb_remove(struct pci_dev *pd)
 	
 	NVTRACE_ENTER();
 
+	riva_bl_exit(par);
+
 #ifdef CONFIG_FB_RIVA_I2C
 	riva_delete_i2c_busses(par);
 	kfree(par->EDID);

include/asm-powerpc/backlight.h

@@ -2,30 +2,30 @@
  * Routines for handling backlight control on PowerBooks
  *
  * For now, implementation resides in
- * arch/powerpc/platforms/powermac/pmac_support.c
+ * arch/powerpc/platforms/powermac/backlight.c
  *
  */
 #ifndef __ASM_POWERPC_BACKLIGHT_H
 #define __ASM_POWERPC_BACKLIGHT_H
 #ifdef __KERNEL__
 
-/* Abstract values */
-#define BACKLIGHT_OFF	0
-#define BACKLIGHT_MIN	1
-#define BACKLIGHT_MAX	0xf
+#include <linux/fb.h>
+#include <linux/mutex.h>
 
-struct backlight_controller {
-	int (*set_enable)(int enable, int level, void *data);
-	int (*set_level)(int level, void *data);
-};
+/* For locking instructions, see the implementation file */
+extern struct backlight_device *pmac_backlight;
+extern struct mutex pmac_backlight_mutex;
 
-extern void register_backlight_controller(struct backlight_controller *ctrler, void *data, char *type);
-extern void unregister_backlight_controller(struct backlight_controller *ctrler, void *data);
+extern void pmac_backlight_calc_curve(struct fb_info*);
+extern int pmac_backlight_curve_lookup(struct fb_info *info, int value);
 
-extern int set_backlight_enable(int enable);
-extern int get_backlight_enable(void);
-extern int set_backlight_level(int level);
-extern int get_backlight_level(void);
+extern int pmac_has_backlight_type(const char *type);
+
+extern void pmac_backlight_key_up(void);
+extern void pmac_backlight_key_down(void);
+
+extern int pmac_backlight_set_legacy_brightness(int brightness);
+extern int pmac_backlight_get_legacy_brightness(void);
 
 #endif /* __KERNEL__ */
 #endif

include/linux/fb.h

 #ifndef _LINUX_FB_H
 #define _LINUX_FB_H
 
+#include <linux/backlight.h>
 #include <asm/types.h>
 
 /* Definitions of frame buffers						*/
@@ -366,6 +367,12 @@ struct fb_cursor {
 	struct fb_image	image;	/* Cursor image */
 };
 
+#ifdef CONFIG_FB_BACKLIGHT
+/* Settings for the generic backlight code */
+#define FB_BACKLIGHT_LEVELS	128
+#define FB_BACKLIGHT_MAX	0xFF
+#endif
+
 #ifdef __KERNEL__
 
 #include <linux/fs.h>
@@ -756,6 +763,21 @@ struct fb_info {
 	struct fb_cmap cmap;		/* Current cmap */
 	struct list_head modelist;      /* mode list */
 	struct fb_videomode *mode;	/* current mode */
+
+#ifdef CONFIG_FB_BACKLIGHT
+	/* Lock ordering:
+	 * bl_mutex (protects bl_dev and bl_curve)
+	 *   bl_dev->sem (backlight class)
+	 */
+	struct mutex bl_mutex;
+
+	/* assigned backlight device */
+	struct backlight_device *bl_dev;
+
+	/* Backlight level curve */
+	u8 bl_curve[FB_BACKLIGHT_LEVELS];
+#endif
+
 	struct fb_ops *fbops;
 	struct device *device;
 	struct class_device *class_device; /* sysfs per device attrs */
@@ -895,6 +917,7 @@ extern struct fb_info *framebuffer_alloc(size_t size, struct device *dev);
 extern void framebuffer_release(struct fb_info *info);
 extern int fb_init_class_device(struct fb_info *fb_info);
 extern void fb_cleanup_class_device(struct fb_info *head);
+extern void fb_bl_default_curve(struct fb_info *fb_info, u8 off, u8 min, u8 max);
 
 /* drivers/video/fbmon.c */
 #define FB_MAXTIMINGS		0

include/linux/pmu.h

@@ -230,4 +230,8 @@ extern int pmu_battery_count;
 extern struct pmu_battery_info pmu_batteries[PMU_MAX_BATTERIES];
 extern unsigned int pmu_power_flags;
 
+/* Backlight */
+extern int disable_kernel_backlight;
+extern void pmu_backlight_init(struct device_node*);
+
 #endif	/* __KERNEL__ */