Bug Labs LCD module backlight support..

Signed-off-by: Matt Isaacs <haveahennessy@gmail.com>

drivers/video/backlight/Kconfig

@@ -307,6 +307,13 @@ config BACKLIGHT_PCF50633
 	  If you have a backlight driven by a NXP PCF50633 MFD, say Y here to
 	  enable its driver.
 
+config BACKLIGHT_BUGBASE2
+        tristate "BUGBASE2 LCD Backlight"
+        depends on BACKLIGHT_CLASS_DEVICE && MACH_BUG20
+        default y
+        help
+        This driver controls the LCD backlight of BUGBASE2
+
 endif # BACKLIGHT_CLASS_DEVICE
 
 endif # BACKLIGHT_LCD_SUPPORT

drivers/video/backlight/Makefile

@@ -35,4 +35,4 @@ obj-$(CONFIG_BACKLIGHT_ADP5520)	+= adp5520_bl.o
 obj-$(CONFIG_BACKLIGHT_ADP8860)	+= adp8860_bl.o
 obj-$(CONFIG_BACKLIGHT_88PM860X) += 88pm860x_bl.o
 obj-$(CONFIG_BACKLIGHT_PCF50633)	+= pcf50633-backlight.o
-
+obj-$(CONFIG_BACKLIGHT_BUGBASE2) 	+= bug_backlight.o

drivers/video/backlight/bug_backlight.c

@@ -0,0 +1,260 @@
+/*
+ * drivers/video/backlight/bug_backlight.c
+ *
+ * Backlight driver for BUGBASE2
+ *
+ * Copyright (c) 2009, Texas Instruments Incorporated.
+ *
+ * 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.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
+ * whether express or implied; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+
+#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 <linux/i2c/twl.h>
+#include <plat/hardware.h>
+
+/**
+ * Name of the driver
+ */
+#define OMAPBL_DRVNAME "omap-backlight"
+
+/**
+ * Name of the device
+ */
+#define OMAPBL_DEVNAME "omap-backlight"
+
+/**
+ * Minimum intensity supported by the panel
+ */
+#define OMAPBL_MIN_INTENSITY   0
+/**
+ * Maximum intensity supported by the panel
+ */
+#define OMAPBL_MAX_INTENSITY   100
+
+/**
+ * Default intensity after boot-up
+ */
+#define OMAPBL_DEF_INTENSITY   70
+
+/**
+ * Flag indicating the driver status - suspended / running
+ */
+#define OMAPBL_SUSPENDED       0x01
+
+
+#define TWL_PWM1_PWM1ON        0x00
+#define TWL_PWM1_PWM1OFF       0x01
+
+/**
+ * Current backlight intensity
+ */
+static int panel_intensity;
+
+/**
+ * Backlight properties
+ */
+static struct backlight_properties omapbl_props;
+
+
+/**
+ * Backlight device
+ */
+struct backlight_device *omapbl_device;
+
+/**
+ * Backlight flags
+ */
+static unsigned long omapbl_flags;
+
+static int omapbl_check_fb(struct backlight_device *bldev, struct fb_info *info)
+{
+	return 0;
+}
+
+static int omapbl_set_intensity(struct backlight_device *bd)
+{
+       int intensity = bd->props.brightness;
+       int ret;
+       u8 c;
+
+       if (bd->props.power != FB_BLANK_UNBLANK)
+               intensity = 0;
+       if (bd->props.fb_blank != FB_BLANK_UNBLANK)
+               intensity = 0;
+       if (omapbl_flags & OMAPBL_SUSPENDED)
+               intensity = 0;
+       if (intensity == 0)
+	       printk("Backlight turned off\n");
+
+       c = ((125 * intensity) / 100) + 2;
+
+#if 0
+	   if (intensity > 100)
+	   {
+		   twl_i2c_read_u8(TWL4030_MODULE_INTBR, &c, 0x0c);
+		   c &= ~(1 << 3);
+		   twl_i2c_write_u8 (TWL4030_MODULE_INTBR, c, 0x0c);
+		   return ret;
+	   }
+#endif
+       /*
+	* Program the OFF register of PWM1 with user values
+	*/
+       ret = twl_i2c_write_u8(TWL4030_MODULE_PWM1, c, TWL_PWM1_PWM1OFF);
+
+       if (ret) {
+	       printk("i2c write failed\n");
+	       return ret;
+       }
+//     printk(KERN_INFO "Backlight altered with value %d.\n", intensity);
+
+       panel_intensity = intensity;
+
+       return 0;
+}
+
+static int omapbl_get_intensity(struct backlight_device *bd)
+{
+       return panel_intensity;
+}
+
+static struct backlight_ops omapbl_ops = {
+       .get_brightness = omapbl_get_intensity,
+       .update_status  = omapbl_set_intensity,
+       .check_fb       = omapbl_check_fb,
+};
+
+static int omapbl_probe(struct platform_device *pdev)
+{
+  	u8 c;
+
+	omapbl_device = backlight_device_register (OMAPBL_DRVNAME,
+                                                       &pdev->dev,
+                                                       NULL,
+                                                       &omapbl_ops,
+						       NULL);
+	if (IS_ERR (omapbl_device))
+		return PTR_ERR (omapbl_device);
+
+	platform_set_drvdata(pdev, omapbl_device);
+
+	omapbl_device->props.power              = FB_BLANK_UNBLANK;
+	omapbl_device->props.max_brightness     = OMAPBL_MAX_INTENSITY;
+	omapbl_device->props.brightness         = OMAPBL_DEF_INTENSITY;
+
+	/* Enable PWM1 and PWM1_CLK in GPBR */
+	twl_i2c_read_u8(TWL4030_MODULE_INTBR, &c, 0x0c);
+	c |= (1 << 3) | (1 << 1);
+	twl_i2c_write_u8 (TWL4030_MODULE_INTBR, c, 0x0c);
+
+	/* Select PWM1 output in PMBR1 */
+	twl_i2c_read_u8(TWL4030_MODULE_INTBR, &c, 0x0d);
+	c |= 0x30;
+	twl_i2c_write_u8 (TWL4030_MODULE_INTBR, c, 0x0d);
+
+	omapbl_set_intensity(omapbl_device);
+
+	printk(KERN_INFO "omap-backlight: device initialized.\n");
+
+	return 0;
+}
+
+static int omapbl_remove(struct platform_device *pdev)
+{
+  u8 c;
+  struct backlight_device *bd = platform_get_drvdata(pdev);
+
+  omapbl_props.power = 0;
+  omapbl_props.brightness = 0;
+  backlight_update_status(bd);
+
+
+  /* Disableable PWM1 and PWM1_CLK in GPBR */
+  twl_i2c_read_u8(TWL4030_MODULE_INTBR, &c, 0x0c);
+  c &= ~((1 << 3) | (1 << 1));
+  twl_i2c_write_u8 (TWL4030_MODULE_INTBR, c, 0x0c);
+
+  /* Restore default/gpio output in PMBR1 */
+  twl_i2c_read_u8(TWL4030_MODULE_INTBR, &c, 0x0d);
+  c &= ~(0x30);
+  twl_i2c_write_u8 (TWL4030_MODULE_INTBR, c, 0x0d);
+
+  backlight_device_unregister(bd);
+
+  printk(KERN_INFO "omap-backlight: device unloaded.\n");
+
+  return 0;
+}
+
+#ifdef CONFIG_PM
+static int omapbl_suspend(struct platform_device *pdev, pm_message_t state)
+{
+       struct backlight_device *bd = platform_get_drvdata(pdev);
+
+       printk(KERN_INFO "omap-backlight: suspending...\n");
+
+       omapbl_flags |= OMAPBL_SUSPENDED;
+       backlight_update_status(bd);
+
+       return 0;
+}
+
+static int omapbl_resume(struct platform_device *pdev)
+{
+       struct backlight_device *bd = platform_get_drvdata(pdev);
+
+       printk(KERN_INFO "omap-backlight: resuming...\n");
+
+       omapbl_flags &= ~OMAPBL_SUSPENDED;
+       backlight_update_status(bd);
+
+       return 0;
+}
+#else
+#define omapbl_suspend NULL
+#define omapbl_resume  NULL
+#endif
+
+static struct platform_driver omap_backlight_drv = {
+       .probe          = omapbl_probe,
+       .remove         = omapbl_remove,
+       .suspend        = omapbl_suspend,
+       .resume         = omapbl_resume,
+       .driver         = {
+                               .name   = OMAPBL_DRVNAME,
+                       },
+};
+
+static struct platform_device *omap_backlight_dev;
+
+static int __init omapbl_init(void)
+{
+       int ret = platform_driver_register(&omap_backlight_drv);
+       return ret;
+}
+
+static void __exit omapbl_exit(void)
+{
+       platform_device_unregister(omap_backlight_dev);
+       platform_driver_unregister(&omap_backlight_drv);
+}
+
+module_init(omapbl_init);
+module_exit(omapbl_exit);
+
+MODULE_AUTHOR("Umesh K");
+MODULE_DESCRIPTION("OMAP LCD Backlight driver");
+MODULE_LICENSE("GPL");
+