From b5a7a466932e9d6da6221785b34854b1838a7061 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Tue, 29 Apr 2014 11:08:32 -0700 Subject: [PATCH] staging: comedi: adv_pci1710: tidy up pci171x_ai_check_chanlist() Tidy up this function to clarify what the chanlist is being checked for. Signed-off-by: H Hartley Sweeten Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/adv_pci1710.c | 81 ++++++++++---------- 1 file changed, 41 insertions(+), 40 deletions(-) diff --git a/drivers/staging/comedi/drivers/adv_pci1710.c b/drivers/staging/comedi/drivers/adv_pci1710.c index 765b1f00255..da1309b8069 100644 --- a/drivers/staging/comedi/drivers/adv_pci1710.c +++ b/drivers/staging/comedi/drivers/adv_pci1710.c @@ -326,60 +326,61 @@ static const unsigned int muxonechan[] = { 0x1818, 0x1919, 0x1a1a, 0x1b1b, 0x1c1c, 0x1d1d, 0x1e1e, 0x1f1f }; -/* -============================================================================== - Check if channel list from user is built correctly - If it's ok, then program scan/gain logic. - This works for all cards. -*/ static int pci171x_ai_check_chanlist(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_cmd *cmd) { + unsigned int chan0 = CR_CHAN(cmd->chanlist[0]); + unsigned int last_aref = CR_AREF(cmd->chanlist[0]); + unsigned int next_chan = (chan0 + 1) % s->n_chan; unsigned int chansegment[32]; - unsigned int i, nowmustbechan, seglen, segpos; - unsigned int *chanlist = cmd->chanlist; - unsigned int n_chan = cmd->chanlist_len; - - /* correct channel and range number check itself comedi/range.c */ - if (n_chan < 1) { - comedi_error(dev, "range/channel list is empty!"); - return 0; - } + unsigned int seglen; + int i; - if (n_chan == 1) + if (cmd->chanlist_len == 1) return 1; /* seglen=1 */ - chansegment[0] = chanlist[0]; /* first channel is every time ok */ - for (i = 1, seglen = 1; i < n_chan; i++, seglen++) { - if (chanlist[0] == chanlist[i]) + /* first channel is always ok */ + chansegment[0] = cmd->chanlist[0]; + + for (i = 1; i < cmd->chanlist_len; i++) { + unsigned int chan = CR_CHAN(cmd->chanlist[i]); + unsigned int aref = CR_AREF(cmd->chanlist[i]); + + if (cmd->chanlist[0] == cmd->chanlist[i]) break; /* we detected a loop, stop */ - if ((CR_CHAN(chanlist[i]) & 1) && - (CR_AREF(chanlist[i]) == AREF_DIFF)) { - comedi_error(dev, "Odd channel cannot be differential input!\n"); + + if (aref == AREF_DIFF && (chan & 1)) { + dev_err(dev->class_dev, + "Odd channel cannot be differential input!\n"); return 0; } - nowmustbechan = (CR_CHAN(chansegment[i - 1]) + 1) % s->n_chan; - if (CR_AREF(chansegment[i - 1]) == AREF_DIFF) - nowmustbechan = (nowmustbechan + 1) % s->n_chan; - if (nowmustbechan != CR_CHAN(chanlist[i])) { - printk("channel list must be continuous! chanlist[%i]=%d but must be %d or %d!\n", - i, CR_CHAN(chanlist[i]), nowmustbechan, - CR_CHAN(chanlist[0])); + + if (last_aref == AREF_DIFF) + next_chan = (next_chan + 1) % s->n_chan; + if (chan != next_chan) { + dev_err(dev->class_dev, + "channel list must be continuous! chanlist[%i]=%d but must be %d or %d!\n", + i, chan, next_chan, chan0); return 0; } - chansegment[i] = chanlist[i]; /* next correct channel in list */ - } - for (i = 0, segpos = 0; i < n_chan; i++) { - if (chanlist[i] != chansegment[i % seglen]) { - printk("bad channel, reference or range number! chanlist[%i]=%d,%d,%d and not %d,%d,%d!\n", - i, CR_CHAN(chansegment[i]), - CR_RANGE(chansegment[i]), - CR_AREF(chansegment[i]), - CR_CHAN(chanlist[i % seglen]), - CR_RANGE(chanlist[i % seglen]), - CR_AREF(chansegment[i % seglen])); + /* next correct channel in list */ + chansegment[i] = cmd->chanlist[i]; + last_aref = aref; + } + seglen = i; + + for (i = 0; i < cmd->chanlist_len; i++) { + if (cmd->chanlist[i] != chansegment[i % seglen]) { + dev_err(dev->class_dev, + "bad channel, reference or range number! chanlist[%i]=%d,%d,%d and not %d,%d,%d!\n", + i, CR_CHAN(chansegment[i]), + CR_RANGE(chansegment[i]), + CR_AREF(chansegment[i]), + CR_CHAN(cmd->chanlist[i % seglen]), + CR_RANGE(cmd->chanlist[i % seglen]), + CR_AREF(chansegment[i % seglen])); return 0; } } -- 2.46.0