lkml.org 
[lkml]   [2019]   [Apr]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH -next] staging: comedi: dyna_pci10xx: remove set but not used variables 'chan' and range'
From
Date
On 06/04/2019 04:07, YueHaibing wrote:
> Fixes gcc '-Wunused-but-set-variable' warning:
>
> drivers/staging/comedi/drivers/dyna_pci10xx.c: In function 'dyna_pci10xx_insn_write_ao':
> drivers/staging/comedi/drivers/dyna_pci10xx.c:109:21: warning:
> variable 'range' set but not used [-Wunused-but-set-variable]
> unsigned int chan, range;
>
> drivers/staging/comedi/drivers/dyna_pci10xx.c:109:15: warning:
> variable 'chan' set but not used [-Wunused-but-set-variable]
> unsigned int chan, range;
>
> They are never used since introduction in commit 16a7373a8e14 ("Staging:
> comedi: add dyna_pci10xx driver")
>
> Signed-off-by: YueHaibing <yuehaibing@huawei.com>
> ---
> drivers/staging/comedi/drivers/dyna_pci10xx.c | 4 ----
> 1 file changed, 4 deletions(-)
>
> diff --git a/drivers/staging/comedi/drivers/dyna_pci10xx.c b/drivers/staging/comedi/drivers/dyna_pci10xx.c
> index 9bdd5bf2eb99..d38bfc6113e8 100644
> --- a/drivers/staging/comedi/drivers/dyna_pci10xx.c
> +++ b/drivers/staging/comedi/drivers/dyna_pci10xx.c
> @@ -106,10 +106,6 @@ static int dyna_pci10xx_insn_write_ao(struct comedi_device *dev,
> {
> struct dyna_pci10xx_private *devpriv = dev->private;
> int n;
> - unsigned int chan, range;
> -
> - chan = CR_CHAN(insn->chanspec);
> - range = range_codes_pci1050_ai[CR_RANGE((insn->chanspec))];
>
> mutex_lock(&devpriv->mutex);
> for (n = 0; n < insn->n; n++) {

That seems fine, thanks. The lines being removed appear to have been
copy and pasted from dyna_pci10xx_insn_read_ai(). The AO subdevice
supports a single range, so no 'range' code is needed. I believe the
card has only one analog output channel[*], so the 'chan' is irrelevant.
This means the 'n_chans' value in the AO subdevice configuration is
incorrect. I'll send a follow-up patch to correct that after Greg KH
takes this one.

[*] Very little information seems to be available about this card
online. It is no longer listed on the manufacturer's web-site and I
couldn't find any archives on archive.org. I found part of a scientific
paper
<http://shodhganga.inflibnet.ac.in/bitstream/10603/150646/15/15_chapter%205.pdf>
which describes the card as having a single channel D/A converter.

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

--
-=( Ian Abbott <abbotti@mev.co.uk> || Web: www.mev.co.uk )=-
-=( MEV Ltd. is a company registered in England & Wales. )=-
-=( Registered number: 02862268. Registered address: )=-
-=( 15 West Park Road, Bramhall, STOCKPORT, SK7 3JZ, UK. )=-

\
 
 \ /
  Last update: 2019-04-06 12:14    [W:0.084 / U:1.936 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site