Messages in this thread | | | Date | Fri, 13 Jan 2012 14:10:19 -0800 | From | Andrew Morton <> | Subject | Re: [PATCH] backlight: Fix the logic to set bits in adp8860_bl and adp8870_bl drivers |
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On Fri, 13 Jan 2012 16:15:21 +0800 Axel Lin <axel.lin@gmail.com> wrote:
> We need to write new value if the bit mask fields of new value is not equal to > old value. It does not make sense to write new value only when all the bit_mask > bits are zero.
When fixing bugs, please always describe the user-visible effects of the bug.
> diff --git a/drivers/video/backlight/adp8860_bl.c b/drivers/video/backlight/adp8860_bl.c > index 66bc74d..378276c 100644 > --- a/drivers/video/backlight/adp8860_bl.c > +++ b/drivers/video/backlight/adp8860_bl.c > @@ -146,7 +146,7 @@ static int adp8860_set_bits(struct i2c_client *client, int reg, uint8_t bit_mask > > ret = adp8860_read(client, reg, ®_val); > > - if (!ret && ((reg_val & bit_mask) == 0)) { > + if (!ret && ((reg_val & bit_mask) != bit_mask)) { > reg_val |= bit_mask; > ret = adp8860_write(client, reg, reg_val); > } > diff --git a/drivers/video/backlight/adp8870_bl.c b/drivers/video/backlight/adp8870_bl.c > index 6c68a68..6735059 100644 > --- a/drivers/video/backlight/adp8870_bl.c > +++ b/drivers/video/backlight/adp8870_bl.c > @@ -160,7 +160,7 @@ static int adp8870_set_bits(struct i2c_client *client, int reg, uint8_t bit_mask > > ret = adp8870_read(client, reg, ®_val); > > - if (!ret && ((reg_val & bit_mask) == 0)) { > + if (!ret && ((reg_val & bit_mask) != bit_mask)) { > reg_val |= bit_mask; > ret = adp8870_write(client, reg, reg_val); > }
This patch is applicable to 3.2.x, but I don't know whether to route it to -stable becasue you didn't tell me what effect the patch has :(
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