Merge branch 'for-linus' of git://git.o-hand.com/linux-rpurdie-backlight

* 'for-linus' of git://git.o-hand.com/linux-rpurdie-backlight:
  backlight: Add OMAP1 PWL backlight driver
  backlight: Avoid unecessary driver callbacks

drivers/video/backlight/Kconfig

@@ -80,6 +80,15 @@ config BACKLIGHT_LOCOMO
 	  If you have a Sharp Zaurus SL-5500 (Collie) or SL-5600 (Poodle) say y to
 	  enable the LCD/backlight driver.
 
+config BACKLIGHT_OMAP1
+	tristate "OMAP1 PWL-based LCD Backlight"
+	depends on BACKLIGHT_CLASS_DEVICE && ARCH_OMAP1
+	default y
+	help
+	  This driver controls the LCD backlight level and power for
+	  the PWL module of OMAP1 processors.  Say Y if your board
+	  uses this hardware.
+
 config BACKLIGHT_HP680
 	tristate "HP Jornada 680 Backlight Driver"
 	depends on BACKLIGHT_CLASS_DEVICE && SH_HP6XX

drivers/video/backlight/Makefile

@@ -7,5 +7,6 @@ obj-$(CONFIG_BACKLIGHT_CLASS_DEVICE) += backlight.o
 obj-$(CONFIG_BACKLIGHT_CORGI)	+= corgi_bl.o
 obj-$(CONFIG_BACKLIGHT_HP680)	+= hp680_bl.o
 obj-$(CONFIG_BACKLIGHT_LOCOMO)	+= locomolcd.o
+obj-$(CONFIG_BACKLIGHT_OMAP1)	+= omap1_bl.o
 obj-$(CONFIG_BACKLIGHT_PROGEAR) += progear_bl.o
 obj-$(CONFIG_BACKLIGHT_CARILLO_RANCH) += cr_bllcd.o

drivers/video/backlight/backlight.c

@@ -94,8 +94,10 @@ static ssize_t backlight_store_power(struct device *dev,
 	mutex_lock(&bd->ops_lock);
 	if (bd->ops) {
 		pr_debug("backlight: set power to %d\n", power);
-		bd->props.power = power;
-		backlight_update_status(bd);
+		if (bd->props.power != power) {
+			bd->props.power = power;
+			backlight_update_status(bd);
+		}
 		rc = count;
 	}
 	mutex_unlock(&bd->ops_lock);
@@ -132,8 +134,10 @@ static ssize_t backlight_store_brightness(struct device *dev,
 		else {
 			pr_debug("backlight: set brightness to %d\n",
 				 brightness);
-			bd->props.brightness = brightness;
-			backlight_update_status(bd);
+			if (bd->props.brightness != brightness) {
+				bd->props.brightness = brightness;
+				backlight_update_status(bd);
+			}
 			rc = count;
 		}
 	}

drivers/video/backlight/omap1_bl.c

+/*
+ * Backlight driver for OMAP based boards.
+ *
+ * Copyright (c) 2006 Andrzej Zaborowski  <balrog@zabor.org>
+ *
+ * This package is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This package is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this package; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/fb.h>
+#include <linux/backlight.h>
+
+#include <asm/arch/hardware.h>
+#include <asm/arch/board.h>
+#include <asm/arch/mux.h>
+
+#define OMAPBL_MAX_INTENSITY		0xff
+
+struct omap_backlight {
+	int powermode;
+	int current_intensity;
+
+	struct device *dev;
+	struct omap_backlight_config *pdata;
+};
+
+static void inline omapbl_send_intensity(int intensity)
+{
+	omap_writeb(intensity, OMAP_PWL_ENABLE);
+}
+
+static void inline omapbl_send_enable(int enable)
+{
+	omap_writeb(enable, OMAP_PWL_CLK_ENABLE);
+}
+
+static void omapbl_blank(struct omap_backlight *bl, int mode)
+{
+	if (bl->pdata->set_power)
+		bl->pdata->set_power(bl->dev, mode);
+
+	switch (mode) {
+	case FB_BLANK_NORMAL:
+	case FB_BLANK_VSYNC_SUSPEND:
+	case FB_BLANK_HSYNC_SUSPEND:
+	case FB_BLANK_POWERDOWN:
+		omapbl_send_intensity(0);
+		omapbl_send_enable(0);
+		break;
+
+	case FB_BLANK_UNBLANK:
+		omapbl_send_intensity(bl->current_intensity);
+		omapbl_send_enable(1);
+		break;
+	}
+}
+
+#ifdef CONFIG_PM
+static int omapbl_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct backlight_device *dev = platform_get_drvdata(pdev);
+	struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
+
+	omapbl_blank(bl, FB_BLANK_POWERDOWN);
+	return 0;
+}
+
+static int omapbl_resume(struct platform_device *pdev)
+{
+	struct backlight_device *dev = platform_get_drvdata(pdev);
+	struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
+
+	omapbl_blank(bl, bl->powermode);
+	return 0;
+}
+#else
+#define omapbl_suspend	NULL
+#define omapbl_resume	NULL
+#endif
+
+static int omapbl_set_power(struct backlight_device *dev, int state)
+{
+	struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
+
+	omapbl_blank(bl, state);
+	bl->powermode = state;
+
+	return 0;
+}
+
+static int omapbl_update_status(struct backlight_device *dev)
+{
+	struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
+
+	if (bl->current_intensity != dev->props.brightness) {
+		if (bl->powermode == FB_BLANK_UNBLANK)
+			omapbl_send_intensity(dev->props.brightness);
+		bl->current_intensity = dev->props.brightness;
+	}
+
+	if (dev->props.fb_blank != bl->powermode)
+		omapbl_set_power(dev, dev->props.fb_blank);
+
+	return 0;
+}
+
+static int omapbl_get_intensity(struct backlight_device *dev)
+{
+	struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
+	return bl->current_intensity;
+}
+
+static struct backlight_ops omapbl_ops = {
+	.get_brightness = omapbl_get_intensity,
+	.update_status  = omapbl_update_status,
+};
+
+static int omapbl_probe(struct platform_device *pdev)
+{
+	struct backlight_device *dev;
+	struct omap_backlight *bl;
+	struct omap_backlight_config *pdata = pdev->dev.platform_data;
+
+	if (!pdata)
+		return -ENXIO;
+
+	omapbl_ops.check_fb = pdata->check_fb;
+
+	bl = kzalloc(sizeof(struct omap_backlight), GFP_KERNEL);
+	if (unlikely(!bl))
+		return -ENOMEM;
+
+	dev = backlight_device_register("omap-bl", &pdev->dev, bl, &omapbl_ops);
+	if (IS_ERR(dev)) {
+		kfree(bl);
+		return PTR_ERR(dev);
+	}
+
+	bl->powermode = FB_BLANK_POWERDOWN;
+	bl->current_intensity = 0;
+
+	bl->pdata = pdata;
+	bl->dev = &pdev->dev;
+
+	platform_set_drvdata(pdev, dev);
+
+	omap_cfg_reg(PWL);	/* Conflicts with UART3 */
+
+	dev->props.fb_blank = FB_BLANK_UNBLANK;
+	dev->props.max_brightness = OMAPBL_MAX_INTENSITY;
+	dev->props.brightness = pdata->default_intensity;
+	omapbl_update_status(dev);
+
+	printk(KERN_INFO "OMAP LCD backlight initialised\n");
+
+	return 0;
+}
+
+static int omapbl_remove(struct platform_device *pdev)
+{
+	struct backlight_device *dev = platform_get_drvdata(pdev);
+	struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
+
+	backlight_device_unregister(dev);
+	kfree(bl);
+
+	return 0;
+}
+
+static struct platform_driver omapbl_driver = {
+	.probe		= omapbl_probe,
+	.remove		= omapbl_remove,
+	.suspend	= omapbl_suspend,
+	.resume		= omapbl_resume,
+	.driver		= {
+		.name	= "omap-bl",
+	},
+};
+
+static int __init omapbl_init(void)
+{
+	return platform_driver_register(&omapbl_driver);
+}
+
+static void __exit omapbl_exit(void)
+{
+	platform_driver_unregister(&omapbl_driver);
+}
+
+module_init(omapbl_init);
+module_exit(omapbl_exit);
+
+MODULE_AUTHOR("Andrzej Zaborowski <balrog@zabor.org>");
+MODULE_DESCRIPTION("OMAP LCD Backlight driver");
+MODULE_LICENSE("GPL");