On 2014-04-15 18:37, H Hartley Sweeten wrote:
Step 5 of the (*do_cmdtest) 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 the sanity check is not needed.For aesthetics, factor the step 5 code into a helper function. Tidy up the factored out code. Also, remove the unnecessary chanlist sanity check in Step 3. Signed-off-by: H Hartley Sweeten <hswee...@visionengravers.com> Cc: Ian Abbott <abbo...@mev.co.uk> Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- drivers/staging/comedi/drivers/gsc_hpdi.c | 36 ++++++++++++++++++------------- 1 file changed, 21 insertions(+), 15 deletions(-) diff --git a/drivers/staging/comedi/drivers/gsc_hpdi.c b/drivers/staging/comedi/drivers/gsc_hpdi.c index 08d7655..7cf8459 100644 --- a/drivers/staging/comedi/drivers/gsc_hpdi.c +++ b/drivers/staging/comedi/drivers/gsc_hpdi.c @@ -360,12 +360,30 @@ static int gsc_hpdi_cmd(struct comedi_device *dev, return 0; } +static int gsc_hpdi_check_chanlist(struct comedi_device *dev, + struct comedi_subdevice *s, + struct comedi_cmd *cmd) +{ + int i; + + for (i = 0; i < cmd->chanlist_len; i++) { + unsigned int chan = CR_CHAN(cmd->chanlist[i]); + + if (chan != i) { + /* XXX could support 8 or 16 channels */ + dev_err(dev->class_dev, + "chanlist must be ch 0 to 31 in order\n"); + return -EINVAL; + } + } + return 0; +} + static int gsc_hpdi_cmd_test(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_cmd *cmd) { int err = 0; - int i; if (s->io_bits) return -EINVAL; @@ -392,10 +410,6 @@ static int gsc_hpdi_cmd_test(struct comedi_device *dev, /* Step 3: check if arguments are trivially valid */ - if (!cmd->chanlist_len || !cmd->chanlist) { - cmd->chanlist_len = 32; - err |= -EINVAL; - } err |= cfc_check_trigger_arg_is(&cmd->scan_end_arg, cmd->chanlist_len); if (cmd->stop_src == TRIG_COUNT) @@ -411,17 +425,9 @@ static int gsc_hpdi_cmd_test(struct comedi_device *dev, if (err) return 4; - /* step 5: complain about special chanlist considerations */ + /* Step 5: check channel list */ - for (i = 0; i < cmd->chanlist_len; i++) { - if (CR_CHAN(cmd->chanlist[i]) != i) { - /* XXX could support 8 or 16 channels */ - dev_err(dev->class_dev, - "chanlist must be ch 0 to 31 in order"); - err |= -EINVAL; - break; - } - } + err |= gsc_hpdi_check_chanlist(dev, s, cmd); if (err) return 5;
As for the remarks in patch 02, it's possible for chanlist to be NULL or for chanlist_len to be 0, so gsc_hpdi_check_chanlist() should only be called if chanlist is non-NULL and chanlist_len is non-0.
Actually in this case, it seems safe to call gsc_hpdi_check_chanlist() if chanlist_len is 0, so only chanlist needs to be checked.
Also, if chanlist is forced to be NULL by __comedi_get_user_chanlist() when chanlist_len is 0, it would be sufficient to check that chanlist is non-NULL before calling pci9111_ai_check_chanlist().
-- -=( Ian Abbott @ MEV Ltd. E-mail: <abbo...@mev.co.uk> )=- -=( Tel: +44 (0)161 477 1898 FAX: +44 (0)161 718 3587 )=- _______________________________________________ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
