Re: [patch] staging: comedi: pcl812: missing break statement

Ian Abbott
2013-08-21T11:35:22Z

On 2013-08-21 11:44, Ian Abbott wrote:
> On 2013-08-21 09:28, Dan Carpenter wrote:
>> Smatch complains that there is a missing break statement here.
>>
>> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
>> ---
>> This looks correct to me, but please double check.
>>
>> diff --git a/drivers/staging/comedi/drivers/pcl812.c b/drivers/staging/comedi/drivers/pcl812.c
>> index 35251e7..03a0989 100644
>> --- a/drivers/staging/comedi/drivers/pcl812.c
>> +++ b/drivers/staging/comedi/drivers/pcl812.c
>> @@ -1404,6 +1404,7 @@ no_dma:
>> if (it->options[3] > 0)
>> /* we use external trigger */
>> devpriv->use_ext_trg = 1;
>> + break;
>> case boardA821:
>> devpriv->max_812_ai_mode0_rangewait = 1;
>> devpriv->mode_reg_int = (irq << 4) & 0xf0;
>>
>
> The missing break might be deliberate; I'll need to track down the
> manuals for the affected cards. case boardACL8216 in the same switch
> also has no break.

After examining the manuals for the affected boards (the formatting of
the manual for PCL-812 and PCL-812PG is dreadful!), the 'break' before
'case boardA821' does seem to be missing, although the bug is harmless
as it only affects some "don't care" bits in a hardware register
(PCL812_MODE at offset 11) for the cases that fall through to here, and
they assign devpriv->max_812_ai_mode0_rangewait to the same value (1).

The other fall through from 'case boardACL8216' to 'case boardPCL812PG'
in this switch seems to be deliberate.

Acked-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>

(whichever is appropriate)

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