Introduce a helper function to load the analog output FIFO.
This fixes a bug in cb_pcidas_ao_inttrig(). That function was writing
'num_bytes' data values to the FIFO instead of 'num_points'. This results
in twice the number of data values getting written to the FIFO.
Use comedi_buf_read_samples() read the analog output samples from the async
buffer.
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/cb_pcidas.c | 54 ++++++++++++------------------
1 file changed, 22 insertions(+), 32 deletions(-)
diff --git a/drivers/staging/comedi/drivers/cb_pcidas.c
b/drivers/staging/comedi/drivers/cb_pcidas.c
index e7ab6bc..a0d462f 100644
--- a/drivers/staging/comedi/drivers/cb_pcidas.c
+++ b/drivers/staging/comedi/drivers/cb_pcidas.c
@@ -1134,32 +1134,39 @@ static int cb_pcidas_cancel(struct comedi_device *dev,
return 0;
}
+static void cb_pcidas_ao_load_fifo(struct comedi_device *dev,
+ struct comedi_subdevice *s,
+ unsigned int nsamples)
+{
+ struct cb_pcidas_private *devpriv = dev->private;
+ struct comedi_cmd *cmd = &s->async->cmd;
+ unsigned int nbytes;
+
+ if (cmd->stop_src == TRIG_COUNT && devpriv->ao_count < nsamples)
+ nsamples = devpriv->ao_count;
+
+ nbytes = comedi_buf_read_samples(s, devpriv->ao_buffer, nsamples);
+ nsamples = nbytes / bytes_per_sample(s);
+ if (cmd->stop_src == TRIG_COUNT)
+ devpriv->ao_count -= nsamples;
+
+ outsw(devpriv->ao_registers + DACDATA, devpriv->ao_buffer, nsamples);
+}
+
static int cb_pcidas_ao_inttrig(struct comedi_device *dev,
struct comedi_subdevice *s,
unsigned int trig_num)
{
const struct cb_pcidas_board *thisboard = dev->board_ptr;
struct cb_pcidas_private *devpriv = dev->private;
- unsigned int num_bytes, num_points = thisboard->fifo_size;
struct comedi_async *async = s->async;
- struct comedi_cmd *cmd = &s->async->cmd;
+ struct comedi_cmd *cmd = &async->cmd;
unsigned long flags;
if (trig_num != cmd->start_arg)
return -EINVAL;
- /* load up fifo */
- if (cmd->stop_src == TRIG_COUNT && devpriv->ao_count < num_points)
- num_points = devpriv->ao_count;
-
- num_bytes = cfc_read_array_from_buffer(s, devpriv->ao_buffer,
- num_points * sizeof(short));
- num_points = num_bytes / sizeof(short);
-
- if (cmd->stop_src == TRIG_COUNT)
- devpriv->ao_count -= num_points;
- /* write data to board's fifo */
- outsw(devpriv->ao_registers + DACDATA, devpriv->ao_buffer, num_bytes);
+ cb_pcidas_ao_load_fifo(dev, s, thisboard->fifo_size);
/* enable dac half-full and empty interrupts */
spin_lock_irqsave(&dev->spinlock, flags);
@@ -1275,8 +1282,6 @@ static void handle_ao_interrupt(struct comedi_device
*dev, unsigned int status)
struct comedi_subdevice *s = dev->write_subdev;
struct comedi_async *async = s->async;
struct comedi_cmd *cmd = &async->cmd;
- unsigned int half_fifo = thisboard->fifo_size / 2;
- unsigned int num_points;
unsigned long flags;
if (status & DAEMI) {
@@ -1295,23 +1300,8 @@ static void handle_ao_interrupt(struct comedi_device
*dev, unsigned int status)
async->events |= COMEDI_CB_EOA;
}
} else if (status & DAHFI) {
- unsigned int num_bytes;
+ cb_pcidas_ao_load_fifo(dev, s, thisboard->fifo_size / 2);
- /* figure out how many points we are writing to fifo */
- num_points = half_fifo;
- if (cmd->stop_src == TRIG_COUNT &&
- devpriv->ao_count < num_points)
- num_points = devpriv->ao_count;
- num_bytes =
- cfc_read_array_from_buffer(s, devpriv->ao_buffer,
- num_points * sizeof(short));
- num_points = num_bytes / sizeof(short);
-
- if (cmd->stop_src == TRIG_COUNT)
- devpriv->ao_count -= num_points;
- /* write data to board's fifo */
- outsw(devpriv->ao_registers + DACDATA, devpriv->ao_buffer,
- num_points);
/* clear half-full interrupt latch */
spin_lock_irqsave(&dev->spinlock, flags);
outw(devpriv->adc_fifo_bits | DAHFI,
--
2.0.3
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