backlight/pandora_bl.c: update to mainline version

..that will hopefully appear in 3.4

diff --git a/drivers/video/backlight/pandora_bl.c b/drivers/video/backlight/pandora_bl.c
index eb56e62..4ec3074 100644 (file)
--- a/drivers/video/backlight/pandora_bl.c
+++ b/drivers/video/backlight/pandora_bl.c
@@ -1,8 +1,9 @@
 /*
- * Backlight driver for TWL4030 PWM0 -> TPS61161 combo.
+ * Backlight driver for Pandora handheld.
+ * Pandora uses TWL4030 PWM0 -> TPS61161 combo for control backlight.
  * Based on pwm_bl.c
  *
- * Author: Gražvydas Ignotas <notasas@gmail.com>
+ * Copyright 2009,2012 Gražvydas Ignotas <notasas@gmail.com>
  *
  * 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
@@ -18,62 +19,58 @@
 #include <linux/i2c/twl.h>
 #include <linux/err.h>
 
-#define TWL_PWM0_ON    0x00
-#define TWL_PWM0_OFF   0x01
+#define TWL_PWM0_ON            0x00
+#define TWL_PWM0_OFF           0x01
 
-#define TWL_INTBR_GPBR1        0x0c
-#define TWL_INTBR_PMBR1        0x0d
+#define TWL_INTBR_GPBR1                0x0c
+#define TWL_INTBR_PMBR1                0x0d
 
-#define PWM0_CLK_ENABLE        1
-#define PWM0_ENABLE    4
+#define TWL_PMBR1_PWM0_MUXMASK 0x0c
+#define TWL_PMBR1_PWM0         0x04
+#define PWM0_CLK_ENABLE                BIT(0)
+#define PWM0_ENABLE            BIT(2)
 
 /* range accepted by hardware */
 #define MIN_VALUE 9
 #define MAX_VALUE 63
 #define MAX_USER_VALUE (MAX_VALUE - MIN_VALUE)
 
-static int old_brightness;
+#define PANDORABL_WAS_OFF BL_CORE_DRIVER1
 
-static void pwm0_disable(void)
-{
-       u8 r;
-
-       /* first disable PWM0 output, then clock */
-       twl_i2c_read_u8(TWL4030_MODULE_INTBR, &r, TWL_INTBR_GPBR1);
-       r &= ~PWM0_ENABLE;
-       twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1);
-       r &= ~PWM0_CLK_ENABLE;
-       twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1);
-}
-
-static int pwm0_backlight_update_status(struct backlight_device *bl)
+static int pandora_backlight_update_status(struct backlight_device *bl)
 {
        int brightness = bl->props.brightness;
        u8 r;
 
        if (bl->props.power != FB_BLANK_UNBLANK)
                brightness = 0;
-       if (bl->props.state & BL_CORE_SUSPENDED)
+       if (bl->props.state & BL_CORE_FBBLANK)
                brightness = 0;
-
-       /* ignore fb blank for now
-       if (bl->props.fb_blank != FB_BLANK_UNBLANK)
+       if (bl->props.state & BL_CORE_SUSPENDED)
                brightness = 0;
-       */
 
        if ((unsigned int)brightness > MAX_USER_VALUE)
                brightness = MAX_USER_VALUE;
 
        if (brightness == 0) {
-               if (old_brightness != 0)
-                       pwm0_disable();
+               if (bl->props.state & PANDORABL_WAS_OFF)
+                       goto done;
+
+               /* first disable PWM0 output, then clock */
+               twl_i2c_read_u8(TWL4030_MODULE_INTBR, &r, TWL_INTBR_GPBR1);
+               r &= ~PWM0_ENABLE;
+               twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1);
+               r &= ~PWM0_CLK_ENABLE;
+               twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1);
 
                goto done;
        }
 
-       if (old_brightness == 0) {
-               /* set PWM duty cycle to max. TPS61161 seems to use this
-                * to calibrate it's PWM sensitivity when it starts. */
+       if (bl->props.state & PANDORABL_WAS_OFF) {
+               /*
+                * set PWM duty cycle to max. TPS61161 seems to use this
+                * to calibrate it's PWM sensitivity when it starts.
+                */
                twl_i2c_write_u8(TWL4030_MODULE_PWM0, MAX_VALUE,
                                        TWL_PWM0_OFF);
 
@@ -85,32 +82,38 @@ static int pwm0_backlight_update_status(struct backlight_device *bl)
                r |= PWM0_ENABLE;
                twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1);
 
-               /* TI made it very easy to enable digital control, so easy that
+               /*
+                * TI made it very easy to enable digital control, so easy that
                 * it often triggers unintentionally and disabes PWM control,
-                * so wait until 1 wire mode detection window ends. */
-               udelay(2000);
+                * so wait until 1 wire mode detection window ends.
+                */
+               usleep_range(2000, 10000);
        }
 
        twl_i2c_write_u8(TWL4030_MODULE_PWM0, MIN_VALUE + brightness,
                                TWL_PWM0_OFF);
 
 done:
-       old_brightness = brightness;
+       if (brightness != 0)
+               bl->props.state &= ~PANDORABL_WAS_OFF;
+       else
+               bl->props.state |= PANDORABL_WAS_OFF;
+
        return 0;
 }
 
-static int pwm0_backlight_get_brightness(struct backlight_device *bl)
+static int pandora_backlight_get_brightness(struct backlight_device *bl)
 {
        return bl->props.brightness;
 }
 
-static const struct backlight_ops pwm0_backlight_ops = {
+static const struct backlight_ops pandora_backlight_ops = {
        .options        = BL_CORE_SUSPENDRESUME,
-       .update_status  = pwm0_backlight_update_status,
-       .get_brightness = pwm0_backlight_get_brightness,
+       .update_status  = pandora_backlight_update_status,
+       .get_brightness = pandora_backlight_get_brightness,
 };
 
-static int pwm0_backlight_probe(struct platform_device *pdev)
+static int pandora_backlight_probe(struct platform_device *pdev)
 {
        struct backlight_properties props;
        struct backlight_device *bl;
@@ -120,7 +123,7 @@ static int pwm0_backlight_probe(struct platform_device *pdev)
        props.max_brightness = MAX_USER_VALUE;
        props.type = BACKLIGHT_RAW;
        bl = backlight_device_register(pdev->name, &pdev->dev,
-                       NULL, &pwm0_backlight_ops, &props);
+                       NULL, &pandora_backlight_ops, &props);
        if (IS_ERR(bl)) {
                dev_err(&pdev->dev, "failed to register backlight\n");
                return PTR_ERR(bl);
@@ -131,46 +134,38 @@ static int pwm0_backlight_probe(struct platform_device *pdev)
        /* 64 cycle period, ON position 0 */
        twl_i2c_write_u8(TWL4030_MODULE_PWM0, 0x80, TWL_PWM0_ON);
 
+       bl->props.state |= PANDORABL_WAS_OFF;
        bl->props.brightness = MAX_USER_VALUE;
        backlight_update_status(bl);
 
-       /* enable PWM function in pin mux (i2c addr 0x49 0x92) */
+       /* enable PWM function in pin mux */
        twl_i2c_read_u8(TWL4030_MODULE_INTBR, &r, TWL_INTBR_PMBR1);
-       r &= ~0x0c;
-       r |= 0x04;
+       r &= ~TWL_PMBR1_PWM0_MUXMASK;
+       r |= TWL_PMBR1_PWM0;
        twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_PMBR1);
 
        return 0;
 }
 
-static int pwm0_backlight_remove(struct platform_device *pdev)
+static int pandora_backlight_remove(struct platform_device *pdev)
 {
        struct backlight_device *bl = platform_get_drvdata(pdev);
        backlight_device_unregister(bl);
        return 0;
 }
 
-static struct platform_driver pwm0_backlight_driver = {
+static struct platform_driver pandora_backlight_driver = {
        .driver         = {
-               .name   = "twl4030-pwm0-bl",
+               .name   = "pandora-backlight",
                .owner  = THIS_MODULE,
        },
-       .probe          = pwm0_backlight_probe,
-       .remove         = pwm0_backlight_remove,
+       .probe          = pandora_backlight_probe,
+       .remove         = pandora_backlight_remove,
 };
 
-static int __init pwm0_backlight_init(void)
-{
-       return platform_driver_register(&pwm0_backlight_driver);
-}
-module_init(pwm0_backlight_init);
-
-static void __exit pwm0_backlight_exit(void)
-{
-       platform_driver_unregister(&pwm0_backlight_driver);
-}
-module_exit(pwm0_backlight_exit);
+module_platform_driver(pandora_backlight_driver);
 
-MODULE_DESCRIPTION("TWL4030 PWM0 Backlight Driver");
+MODULE_AUTHOR("Gražvydas Ignotas <notasas@gmail.com>");
+MODULE_DESCRIPTION("Pandora Backlight Driver");
 MODULE_LICENSE("GPL");
-MODULE_ALIAS("platform:twl4030-pwm0-bl");
+MODULE_ALIAS("platform:pandora-backlight");