From c9d44c8b43d29dd500c1dd711e490bdcd47f2830 Mon Sep 17 00:00:00 2001 From: Andy Green Date: Tue, 13 May 2008 18:53:40 +0100 Subject: [PATCH] fix-backlight-disable-on-zero-intensity.patch It's never right to put 0 intensity into LEDOUT according to datasheet But having a floor at intensity 2 means backlight isn't properly off when "dimmed". So change to intensity 0 --> disable backlight. Signed-off-by: Andy Green --- drivers/i2c/chips/pcf50633.c | 34 +++++++++++++++++++++------------- 1 files changed, 21 insertions(+), 13 deletions(-) diff --git a/drivers/i2c/chips/pcf50633.c b/drivers/i2c/chips/pcf50633.c index dc4ea0a..205f4e3 100644 --- a/drivers/i2c/chips/pcf50633.c +++ b/drivers/i2c/chips/pcf50633.c @@ -1458,6 +1458,9 @@ static int pcf50633bl_get_intensity(struct backlight_device *bd) struct pcf50633_data *pcf = bl_get_data(bd); int intensity = reg_read(pcf, PCF50633_REG_LEDOUT); + if (!(reg_read(pcf, PCF50633_REG_LEDOUT) & 1)) + intensity = 0; + return intensity & 0x3f; } @@ -1466,31 +1469,36 @@ static int pcf50633bl_set_intensity(struct backlight_device *bd) struct pcf50633_data *pcf = bl_get_data(bd); int intensity = bd->props.brightness; int old_intensity = reg_read(pcf, PCF50633_REG_LEDOUT); - u_int8_t ledena = 2; int ret; - if (bd->props.power != FB_BLANK_UNBLANK) - intensity = 0; - if (bd->props.fb_blank != FB_BLANK_UNBLANK) + if (!(reg_read(pcf, PCF50633_REG_LEDOUT) & 1)) + old_intensity = 0; + + if ((bd->props.power != FB_BLANK_UNBLANK) || + (bd->props.fb_blank != FB_BLANK_UNBLANK)) intensity = 0; - /* The PCF50633 cannot handle LEDOUT = 0 (datasheet p60) + /* + * The PCF50633 cannot handle LEDOUT = 0 (datasheet p60) * if seen, you have to re-enable the LED unit + * we treat intensity 0 as disable */ - if (intensity != 0 && old_intensity == 0) { - ledena = reg_read(pcf, PCF50633_REG_LEDENA); - reg_write(pcf, PCF50633_REG_LEDENA, 0x00); + if (intensity && !old_intensity) { + ret = reg_set_bit_mask(pcf, PCF50633_REG_LEDENA, 0x01, 0x00); + if (ret) + return ret; } if (!intensity) /* illegal to set LEDOUT to 0 */ - ret = reg_set_bit_mask(pcf, PCF50633_REG_LEDOUT, 0x3f, 2); - else + ret = reg_set_bit_mask(pcf, PCF50633_REG_LEDENA, 0x01, 0x00); + else { ret = reg_set_bit_mask(pcf, PCF50633_REG_LEDOUT, 0x3f, intensity); - - if (intensity != 0 && old_intensity == 0) - reg_write(pcf, PCF50633_REG_LEDENA, ledena); + if (ret) + return ret; + ret = reg_set_bit_mask(pcf, PCF50633_REG_LEDENA, 0x01, 0x01); + } return ret; } -- 1.5.6.5