[PATCH 16/49] staging: comedi: me4000: cleanup ai_check_chanlist()

[Ian Abbott]

On 2014-04-15 18:37, H Hartley Sweeten wrote:
> This is the Step 5 helper function of the (*do_cmdtest). It validates that
> the chanlist, chan/range/aref/etc, is compatible with the actual hardware.
> At this point in the (*do_cmdtest) the chanlist is valid, due to checks in
> the core, so any sanity checks are not needed.
>
> For aesthetics, rename this function so it has namespace associated with
> the driver and move it closer to the (*do_cmdtest) function.
>
> Tidy it up to function.
>
> Signed-off-by: H Hartley Sweeten <hsweeten at visionengravers.com>
> Cc: Ian Abbott <abbotti at mev.co.uk>
> Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
> ---
>   drivers/staging/comedi/drivers/me4000.c | 96 ++++++++++++++-------------------
>   1 file changed, 40 insertions(+), 56 deletions(-)
>
> diff --git a/drivers/staging/comedi/drivers/me4000.c b/drivers/staging/comedi/drivers/me4000.c
> index 2657e5c..717965b 100644
> --- a/drivers/staging/comedi/drivers/me4000.c
> +++ b/drivers/staging/comedi/drivers/me4000.c
> @@ -598,58 +598,6 @@ static int me4000_ai_cancel(struct comedi_device *dev,
>   	return 0;
>   }
>
> -static int ai_check_chanlist(struct comedi_device *dev,
> -			     struct comedi_subdevice *s, struct comedi_cmd *cmd)
> -{
> -	const struct me4000_board *thisboard = comedi_board(dev);
> -	int aref;
> -	int i;
> -
> -	/* Check whether aref is equal for all entries */
> -	aref = CR_AREF(cmd->chanlist[0]);
> -	for (i = 0; i < cmd->chanlist_len; i++) {
> -		if (CR_AREF(cmd->chanlist[i]) != aref) {
> -			dev_err(dev->class_dev,
> -				"Mode is not equal for all entries\n");
> -			return -EINVAL;
> -		}
> -	}
> -
> -	/* Check whether channels are available for this ending */
> -	if (aref == SDF_DIFF) {
> -		for (i = 0; i < cmd->chanlist_len; i++) {
> -			if (CR_CHAN(cmd->chanlist[i]) >=
> -			    thisboard->ai_diff_nchan) {
> -				dev_err(dev->class_dev,
> -					"Channel number to high\n");
> -				return -EINVAL;
> -			}
> -		}
> -	} else {
> -		for (i = 0; i < cmd->chanlist_len; i++) {
> -			if (CR_CHAN(cmd->chanlist[i]) >= thisboard->ai_nchan) {
> -				dev_err(dev->class_dev,
> -					"Channel number to high\n");
> -				return -EINVAL;
> -			}
> -		}
> -	}
> -
> -	/* Check if bipolar is set for all entries when in differential mode */
> -	if (aref == SDF_DIFF) {
> -		for (i = 0; i < cmd->chanlist_len; i++) {
> -			if (CR_RANGE(cmd->chanlist[i]) != 1 &&
> -			    CR_RANGE(cmd->chanlist[i]) != 2) {
> -				dev_err(dev->class_dev,
> -				       "Bipolar is not selected in differential mode\n");
> -				return -EINVAL;
> -			}
> -		}
> -	}
> -
> -	return 0;
> -}
> -
>   static int ai_round_cmd_args(struct comedi_device *dev,
>   			     struct comedi_subdevice *s,
>   			     struct comedi_cmd *cmd,
> @@ -855,6 +803,41 @@ static int me4000_ai_do_cmd(struct comedi_device *dev,
>   	return 0;
>   }
>
> +static int me4000_ai_check_chanlist(struct comedi_device *dev,
> +				    struct comedi_subdevice *s,
> +				    struct comedi_cmd *cmd)
> +{
> +	const struct me4000_board *board = comedi_board(dev);
> +	unsigned int aref0 = CR_AREF(cmd->chanlist[0]);
> +	int i;
> +
> +	for (i = 0; i < cmd->chanlist_len; i++) {
> +		unsigned int chan = CR_CHAN(cmd->chanlist[i]);
> +		unsigned int range = CR_RANGE(cmd->chanlist[i]);
> +		unsigned int aref = CR_AREF(cmd->chanlist[i]);
> +
> +		if (aref != aref0) {
> +			dev_err(dev->class_dev,
> +				"Mode is not equal for all entries\n");
> +			return -EINVAL;
> +		}
> +
> +		if (aref == SDF_DIFF) {
> +			if (chan >= board->ai_diff_nchan) {
> +				dev_err(dev->class_dev,
> +					"Channel number to high\n");
> +				return -EINVAL;
> +			}
> +			if (!comedi_range_is_bipolar(s, range)) {
> +				dev_err(dev->class_dev,
> +				       "Bipolar is not selected in differential mode\n");
> +				return -EINVAL;
> +			}
> +		}
> +	}
> +	return 0;
> +}
> +
>   static int me4000_ai_do_cmd_test(struct comedi_device *dev,
>   				 struct comedi_subdevice *s,
>   				 struct comedi_cmd *cmd)
> @@ -1069,10 +1052,11 @@ static int me4000_ai_do_cmd_test(struct comedi_device *dev,
>   	if (err)
>   		return 4;
>
> -	/*
> -	 * Stage 5. Check the channel list.
> -	 */
> -	if (ai_check_chanlist(dev, s, cmd))
> +	/* Step 5: check channel list */
> +
> +	err |= me4000_ai_check_chanlist(dev, s, cmd);
> +
> +	if (err)
>   		return 5;
>
>   	return 0;
>

For patch 02 I mentioned that ai_check_chanlist() should only be called 
if chanlist is non-NULL and chanlist_len is non-0, so the same applies 
to the renamed function.

-- 
-=( Ian Abbott @ MEV Ltd.    E-mail: <abbotti at mev.co.uk>        )=-
-=( Tel: +44 (0)161 477 1898   FAX: +44 (0)161 718 3587         )=-