staging: comedi: adl_pci9118: tidy up check_channel_list()

Rename this function to give it namespace associated with the driver.

Currently this function is called by both the AI (*do_cmdtest) and the (*do_cmd)
functions. It really only needs to be called by the (*do_cmdtest) to validate
that the chanlist meets the requirements of the hardware. It's only called by
the (*do_cmd) to verify that the scan length is not to large after adding the
extra samples needed to satisfy the DMA.

Move the extra scan length check into the (*do_cmd) function and remove the
unnecessary parameters 'frontadd' and 'backadd'.

Tidy up the reset of the function.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/drivers/adl_pci9118.c b/drivers/staging/comedi/drivers/adl_pci9118.c
index dcfe5cc08220c447a7da468b0f26f284eaf08506..08cd04691bea559ee35c7ff05cb01ea3ca7c5dbc 100644 (file)
--- a/drivers/staging/comedi/drivers/adl_pci9118.c
+++ b/drivers/staging/comedi/drivers/adl_pci9118.c
@@ -169,11 +169,6 @@ static const struct comedi_lrange pci9118hg_ai_range = {
        }
 };
 
-#define PCI9118_BIPOLAR_RANGES 4       /*
-                                        * used for test on mixture
-                                        * of BIP/UNI ranges
-                                        */
-
 enum pci9118_boardid {
        BOARD_PCI9118DG,
        BOARD_PCI9118HG,
@@ -296,46 +291,44 @@ static void pci9118_ai_reset_fifo(struct comedi_device *dev)
        outl(0, dev->iobase + PCI9118_FIFO_RESET_REG);
 }
 
-static int check_channel_list(struct comedi_device *dev,
-                             struct comedi_subdevice *s, int n_chan,
-                             unsigned int *chanlist, int frontadd, int backadd)
+static int pci9118_ai_check_chanlist(struct comedi_device *dev,
+                                    struct comedi_subdevice *s,
+                                    struct comedi_cmd *cmd)
 {
        struct pci9118_private *devpriv = dev->private;
-       unsigned int i, differencial = 0, bipolar = 0;
+       unsigned int range0 = CR_RANGE(cmd->chanlist[0]);
+       unsigned int aref0 = CR_AREF(cmd->chanlist[0]);
+       int i;
 
-       if ((frontadd + n_chan + backadd) > s->len_chanlist) {
-               dev_err(dev->class_dev,
-                       "range/channel list is too long for actual configuration!\n");
+       /* single channel scans are always ok */
+       if (cmd->chanlist_len == 1)
                return 0;
-       }
 
-       if (CR_AREF(chanlist[0]) == AREF_DIFF)
-               differencial = 1;       /* all input must be diff */
-       if (CR_RANGE(chanlist[0]) < PCI9118_BIPOLAR_RANGES)
-               bipolar = 1;    /* all input must be bipolar */
-       if (n_chan > 1)
-               for (i = 1; i < n_chan; i++) {  /* check S.E/diff */
-                       if ((CR_AREF(chanlist[i]) == AREF_DIFF) !=
-                           (differencial)) {
-                               dev_err(dev->class_dev,
-                                       "Differential and single ended inputs can't be mixed!\n");
-                               return 0;
-                       }
-                       if ((CR_RANGE(chanlist[i]) < PCI9118_BIPOLAR_RANGES) !=
-                           (bipolar)) {
-                               dev_err(dev->class_dev,
-                                       "Bipolar and unipolar ranges can't be mixed!\n");
-                               return 0;
-                       }
-                       if (!devpriv->usemux && differencial &&
-                           (CR_CHAN(chanlist[i]) >= (s->n_chan / 2))) {
-                               dev_err(dev->class_dev,
-                                       "AREF_DIFF is only available for the first 8 channels!\n");
-                               return 0;
-                       }
+       for (i = 1; 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,
+                               "Differential and single ended inputs can't be mixed!\n");
+                       return -EINVAL;
+               }
+               if (comedi_range_is_bipolar(s, range) !=
+                   comedi_range_is_bipolar(s, range0)) {
+                       dev_err(dev->class_dev,
+                               "Bipolar and unipolar ranges can't be mixed!\n");
+                       return -EINVAL;
+               }
+               if (!devpriv->usemux && aref == AREF_DIFF &&
+                   (chan >= (s->n_chan / 2))) {
+                       dev_err(dev->class_dev,
+                               "AREF_DIFF is only available for the first 8 channels!\n");
+                       return -EINVAL;
                }
+       }
 
-       return 1;
+       return 0;
 }
 
 static void pci9118_set_chanlist(struct comedi_device *dev,
@@ -940,6 +933,7 @@ static int pci9118_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
        struct comedi_8254 *pacer = dev->pacer;
        struct comedi_cmd *cmd = &s->async->cmd;
        unsigned int addchans = 0;
+       unsigned int scanlen;
 
        devpriv->ai12_startstop = 0;
        devpriv->ai_flags = cmd->flags;
@@ -1025,19 +1019,20 @@ static int pci9118_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
                }
        }
        /* well, we now know what must be all added */
-       devpriv->ai_n_realscanlen =     /*
-                                        * what we must take from card in real
-                                        * to have cmd->scan_end_arg on output?
-                                        */
-           (devpriv->ai_add_front + cmd->chanlist_len +
-            devpriv->ai_add_back) * (cmd->scan_end_arg /
-                                     cmd->chanlist_len);
-
-       /* check and setup channel list */
-       if (!check_channel_list(dev, s, cmd->chanlist_len,
-                               cmd->chanlist, devpriv->ai_add_front,
-                               devpriv->ai_add_back))
+       scanlen = devpriv->ai_add_front + cmd->chanlist_len +
+                 devpriv->ai_add_back;
+       /*
+        * what we must take from card in real to have cmd->scan_end_arg
+        * on output?
+        */
+       devpriv->ai_n_realscanlen = scanlen *
+                                   (cmd->scan_end_arg / cmd->chanlist_len);
+
+       if (scanlen > s->len_chanlist) {
+               dev_err(dev->class_dev,
+                       "range/channel list is too long for actual configuration!\n");
                return -EINVAL;
+       }
 
        /*
         * Configure analog input and load the chanlist.
@@ -1307,10 +1302,13 @@ static int pci9118_ai_cmdtest(struct comedi_device *dev,
        if (err)
                return 4;
 
+       /* Step 5: check channel list if it exists */
+
        if (cmd->chanlist)
-               if (!check_channel_list(dev, s, cmd->chanlist_len,
-                                       cmd->chanlist, 0, 0))
-                       return 5;       /* incorrect channels list */
+               err |= pci9118_ai_check_chanlist(dev, s, cmd);
+
+       if (err)
+               return 5;
 
        return 0;
 }