staging: comedi: adv_pci1710: transfer all ai samples in one step
authorH Hartley Sweeten <hsweeten@visionengravers.com>
Tue, 20 Jan 2015 21:53:25 +0000 (14:53 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sun, 25 Jan 2015 11:59:12 +0000 (19:59 +0800)
The two step process to transfer the ai samples in pci1710_handle_fifo() doesn't
make any sense. If the async buffer does not have enough room for the samples the
core will set the async event COMEDI_CB_OVERFLOW which will cause the async command
to cancel. Splitting the transfer doesn't add any value.

Transfer all the samples in one step to simplify the code.

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>
drivers/staging/comedi/drivers/adv_pci1710.c

index 0a50053..76075db 100644 (file)
@@ -720,7 +720,6 @@ static void pci1710_handle_fifo(struct comedi_device *dev,
 {
        struct pci1710_private *devpriv = dev->private;
        struct comedi_cmd *cmd = &s->async->cmd;
-       unsigned int nsamples;
        unsigned int m;
 
        m = inw(dev->iobase + PCI171x_STATUS);
@@ -736,18 +735,8 @@ static void pci1710_handle_fifo(struct comedi_device *dev,
                return;
        }
 
-       nsamples = devpriv->max_samples;
-       if (comedi_samples_to_bytes(s, nsamples) >= s->async->prealloc_bufsz) {
-               m = comedi_bytes_to_samples(s, s->async->prealloc_bufsz);
-               if (move_block_from_fifo(dev, s, m))
-                       return;
-               nsamples -= m;
-       }
-
-       if (nsamples) {
-               if (move_block_from_fifo(dev, s, nsamples))
-                       return;
-       }
+       if (move_block_from_fifo(dev, s, devpriv->max_samples))
+               return;
 
        if (cmd->stop_src == TRIG_COUNT &&
            s->async->scans_done >= cmd->stop_arg) {