staging: comedi: das16: pass struct comedi_cmd by reference

Change `das16_suggest_transfer_size()` to take a pointer to the `struct
comedi_cmd` instead of passing it by value.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/drivers/das16.c b/drivers/staging/comedi/drivers/das16.c
index 2a38915c69e8f414e40085e338a80bd3d353ee88..744376a49d082942fe80b794e3660791452d9721 100644 (file)
--- a/drivers/staging/comedi/drivers/das16.c
+++ b/drivers/staging/comedi/drivers/das16.c
@@ -558,7 +558,7 @@ static int das16_cmd_test(struct comedi_device *dev, struct comedi_subdevice *s,
 
 /* utility function that suggests a dma transfer size in bytes */
 static unsigned int das16_suggest_transfer_size(struct comedi_device *dev,
-                                               struct comedi_cmd cmd)
+                                               const struct comedi_cmd *cmd)
 {
        unsigned int size;
        unsigned int freq;
@@ -571,16 +571,16 @@ static unsigned int das16_suggest_transfer_size(struct comedi_device *dev,
 
        /* otherwise, we are relying on dma terminal count interrupt,
         * so pick a reasonable size */
-       if (cmd.convert_src == TRIG_TIMER)
-               freq = 1000000000 / cmd.convert_arg;
-       else if (cmd.scan_begin_src == TRIG_TIMER)
-               freq = (1000000000 / cmd.scan_begin_arg) * cmd.chanlist_len;
+       if (cmd->convert_src == TRIG_TIMER)
+               freq = 1000000000 / cmd->convert_arg;
+       else if (cmd->scan_begin_src == TRIG_TIMER)
+               freq = (1000000000 / cmd->scan_begin_arg) * cmd->chanlist_len;
        /*  return some default value */
        else
                freq = 0xffffffff;
 
-       if (cmd.flags & TRIG_WAKE_EOS) {
-               size = sample_size * cmd.chanlist_len;
+       if (cmd->flags & TRIG_WAKE_EOS) {
+               size = sample_size * cmd->chanlist_len;
        } else {
                /*  make buffer fill in no more than 1/3 second */
                size = (freq / 3) * sample_size;
@@ -592,7 +592,7 @@ static unsigned int das16_suggest_transfer_size(struct comedi_device *dev,
        else if (size < sample_size)
                size = sample_size;
 
-       if (cmd.stop_src == TRIG_COUNT && size > devpriv->adc_byte_count)
+       if (cmd->stop_src == TRIG_COUNT && size > devpriv->adc_byte_count)
                size = devpriv->adc_byte_count;
 
        return size;
@@ -685,7 +685,7 @@ static int das16_cmd_exec(struct comedi_device *dev, struct comedi_subdevice *s)
        set_dma_addr(devpriv->dma_chan,
                     devpriv->dma_buffer_addr[devpriv->current_buffer]);
        /*  set appropriate size of transfer */
-       devpriv->dma_transfer_size = das16_suggest_transfer_size(dev, *cmd);
+       devpriv->dma_transfer_size = das16_suggest_transfer_size(dev, cmd);
        set_dma_count(devpriv->dma_chan, devpriv->dma_transfer_size);
        enable_dma(devpriv->dma_chan);
        release_dma_lock(flags);