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

4 files changed, 228 insertions, 4 deletions

diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index 924e2551044a..dcd8073c2369 100644
--- a/drivers/video/backlight/Kconfig
+++ b/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
diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
index 965a78b18118..33f6c7cecc73 100644
--- a/drivers/video/backlight/Makefile
+++ b/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
diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
index 4840fe217e4d..39394757679c 100644
--- a/drivers/video/backlight/backlight.c
+++ b/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;
                 }
         }
diff --git a/drivers/video/backlight/omap1_bl.c b/drivers/video/backlight/omap1_bl.c
new file mode 100644
index 000000000000..891875d53a49
--- /dev/null
+++ b/drivers/video/backlight/omap1_bl.c
@@ -0,0 +1,210 @@
+/*
+ * 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");