On Mon, Mar 16, 2015 at 02:11:00PM +0000, Ian Abbott wrote:
> commit abe46b8932dd upstream
>
> Reading of analog input channels by the `INSN_READ` comedi instruction
> is broken for all except channel 0. `pci171x_insn_read_ai()` calls
> `pci171x_ai_dropout()` with the wrong value for the third parameter. It
> is supposed to be the current index in a channel list (which is always
> of length 1 in this case, so the index should be 0), but instead it is
> passing the actual channel number. `pci171x_ai_dropout()` checks the
> channel number encoded in the raw sample value read from the hardware
> matches the channel number stored in the specified index of the
> previously set up channel list and returns `-ENODATA` if it doesn't
> match. Since the index should always be 0 in this case, the match will
> fail unless the channel number is also 0. Fix it by passing 0 as the
> channel index.
>
> Fixes: 16c7eb6047bb ("staging: comedi: adv_pci1710: always enable PCI171x_PARANOIDCHECK code")
> Signed-off-by: Ian Abbott <abbotti@xxxxxxxxx>
> ---
> Sorry, the original upstream commit didn't apply!
Thank you, Ian! I'll use this backport for the 3.16 kernel.
Cheers,
--
Luís
> ---
> drivers/staging/comedi/drivers/adv_pci1710.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/staging/comedi/drivers/adv_pci1710.c b/drivers/staging/comedi/drivers/adv_pci1710.c
> index d02df7d..57b7bc2 100644
> --- a/drivers/staging/comedi/drivers/adv_pci1710.c
> +++ b/drivers/staging/comedi/drivers/adv_pci1710.c
> @@ -455,7 +455,6 @@ static int pci171x_insn_read_ai(struct comedi_device *dev,
> struct comedi_insn *insn, unsigned int *data)
> {
> struct pci1710_private *devpriv = dev->private;
> - unsigned int chan = CR_CHAN(insn->chanspec);
> int ret = 0;
> int i;
>
> @@ -477,7 +476,7 @@ static int pci171x_insn_read_ai(struct comedi_device *dev,
> break;
>
> val = inw(dev->iobase + PCI171x_AD_DATA);
> - ret = pci171x_ai_dropout(dev, s, chan, val);
> + ret = pci171x_ai_dropout(dev, s, 0, val);
> if (ret)
> break;
>
> --
> 2.1.4
>
> --
> To unsubscribe from this list: send the line "unsubscribe stable" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html