Here is a minor patch to make the setting of intensity a little more
understandable (to me) :)
Sean
diff --git a/drivers/i2c/chips/pcf50633.c b/drivers/i2c/chips/pcf50633.c
index 950d100..49a0e9b 100644
--- a/drivers/i2c/chips/pcf50633.c
+++ b/drivers/i2c/chips/pcf50633.c
@@ -1880,6 +1880,11 @@ 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) << 2;
+ /* If the LED unit is turned off, then the intensity is 0
+ */
+ if (!(reg_read(pcf, PCF50633_REG_LEDENA) & 1))
+ intensity = 0;
+
return intensity & 0xff;
}
@@ -1887,35 +1892,28 @@ static int pcf50633bl_set_intensity(struct backlight_device *bd)
{
struct pcf50633_data *pcf = bl_get_data(bd);
int intensity = bd->props.brightness >> 2;
- int old_intensity = reg_read(pcf, PCF50633_REG_LEDOUT);
- u_int8_t ledena = 2;
+ u_int8_t old_ledena = reg_read(pcf, PCF50633_REG_LEDENA);
+ u_int8_t ledena = old_ledena;
int ret;
- if (!(reg_read(pcf, PCF50633_REG_LEDENA) & 1))
- old_intensity = 0;
-
+ /* illegal to set LEDOUT to 0 */
if ((bd->props.power != FB_BLANK_UNBLANK) ||
- (bd->props.fb_blank != FB_BLANK_UNBLANK))
- intensity = 0;
+ (bd->props.fb_blank != FB_BLANK_UNBLANK) ||
+ (!intensity)) {
- /* The PCF50633 cannot handle LEDOUT = 0 (datasheet p60)
- * if seen, you have to re-enable the LED unit
- */
+ ledena &= ~1;
- if (intensity != 0 && old_intensity == 0) {
- ledena = reg_read(pcf, PCF50633_REG_LEDENA);
- reg_write(pcf, PCF50633_REG_LEDENA, 0x00);
- }
+ } else {
- 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_LEDOUT, 0x3f,
- intensity);
+ ledena |= 1;
+ }
- if (intensity != 0 && old_intensity == 0)
+ if (ledena != old_ledena)
reg_write(pcf, PCF50633_REG_LEDENA, ledena);
+ ret = reg_set_bit_mask(pcf, PCF50633_REG_LEDOUT, 0x3f,
+ intensity ? intensity : 2);
+
return ret;
}
