target/linux/s3c24xx/patches-2.6.24/1148-fix-backlight-disable-on-zero-intensity.patch.patch

   1 From c9d44c8b43d29dd500c1dd711e490bdcd47f2830 Mon Sep 17 00:00:00 2001
   2 From: Andy Green <andy@openmoko.com>
   3 Date: Tue, 13 May 2008 18:53:40 +0100
   4 Subject: [PATCH] fix-backlight-disable-on-zero-intensity.patch
   5
   6 It's never right to put 0 intensity into LEDOUT according to datasheet
   7 But having a floor at intensity 2 means backlight isn't properly off
   8 when "dimmed".  So change to intensity 0 --> disable backlight.
   9
  10 Signed-off-by: Andy Green <andy@openmoko.com>
  11 ---
  12  drivers/i2c/chips/pcf50633.c |   34 +++++++++++++++++++++-------------
  13  1 files changed, 21 insertions(+), 13 deletions(-)
  14
  15 diff --git a/drivers/i2c/chips/pcf50633.c b/drivers/i2c/chips/pcf50633.c
  16 index dc4ea0a..205f4e3 100644
  17 --- a/drivers/i2c/chips/pcf50633.c
  18 +++ b/drivers/i2c/chips/pcf50633.c
  19 @@ -1458,6 +1458,9 @@ static int pcf50633bl_get_intensity(struct backlight_device *bd)
  20         struct pcf50633_data *pcf = bl_get_data(bd);
  21         int intensity = reg_read(pcf, PCF50633_REG_LEDOUT);
  22
  23 +       if (!(reg_read(pcf, PCF50633_REG_LEDOUT) & 1))
  24 +               intensity = 0;
  25 +
  26         return intensity & 0x3f;
  27  }
  28
  29 @@ -1466,31 +1469,36 @@ static int pcf50633bl_set_intensity(struct backlight_device *bd)
  30         struct pcf50633_data *pcf = bl_get_data(bd);
  31         int intensity = bd->props.brightness;
  32         int old_intensity = reg_read(pcf, PCF50633_REG_LEDOUT);
  33 -       u_int8_t ledena = 2;
  34         int ret;
  35
  36 -       if (bd->props.power != FB_BLANK_UNBLANK)
  37 -               intensity = 0;
  38 -       if (bd->props.fb_blank != FB_BLANK_UNBLANK)
  39 +       if (!(reg_read(pcf, PCF50633_REG_LEDOUT) & 1))
  40 +               old_intensity = 0;
  41 +
  42 +       if ((bd->props.power != FB_BLANK_UNBLANK) ||
  43 +           (bd->props.fb_blank != FB_BLANK_UNBLANK))
  44                 intensity = 0;
  45
  46 -       /* The PCF50633 cannot handle LEDOUT = 0 (datasheet p60)
  47 +       /*
  48 +        * The PCF50633 cannot handle LEDOUT = 0 (datasheet p60)
  49          * if seen, you have to re-enable the LED unit
  50 +        * we treat intensity 0 as disable
  51          */
  52
  53 -       if (intensity != 0 && old_intensity == 0) {
  54 -               ledena = reg_read(pcf, PCF50633_REG_LEDENA);
  55 -               reg_write(pcf, PCF50633_REG_LEDENA, 0x00);
  56 +       if (intensity && !old_intensity) {
  57 +               ret = reg_set_bit_mask(pcf, PCF50633_REG_LEDENA, 0x01, 0x00);
  58 +               if (ret)
  59 +                       return ret;
  60         }
  61
  62         if (!intensity) /* illegal to set LEDOUT to 0 */
  63 -               ret = reg_set_bit_mask(pcf, PCF50633_REG_LEDOUT, 0x3f, 2);
  64 -       else
  65 +               ret = reg_set_bit_mask(pcf, PCF50633_REG_LEDENA, 0x01, 0x00);
  66 +       else {
  67                 ret = reg_set_bit_mask(pcf, PCF50633_REG_LEDOUT, 0x3f,
  68                                intensity);
  69 -
  70 -       if (intensity != 0 && old_intensity == 0)
  71 -               reg_write(pcf, PCF50633_REG_LEDENA, ledena);
  72 +               if (ret)
  73 +                       return ret;
  74 +               ret = reg_set_bit_mask(pcf, PCF50633_REG_LEDENA, 0x01, 0x01);
  75 +       }
  76
  77         return ret;
  78  }
  79 --
  80 1.5.6.5
  81