staging: comedi: cb_pcidas: use comedi_async 'scans_done' to detect AI EOA

Remove the private data member 'count' and use the comedi_async 'scans_done'
member to detect the analog input end-of-acquisition.

Use the comedi_nsamples_left() helper to get the number of samples to actually
add to the async buffer.

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/cb_pcidas.c b/drivers/staging/comedi/drivers/cb_pcidas.c
index 1c38cd5f846c2595a32c16af82836d133846a6c6..e211ef8650c40d82ffb9175c7057ba9ab2d6329d 100644 (file)
--- a/drivers/staging/comedi/drivers/cb_pcidas.c
+++ b/drivers/staging/comedi/drivers/cb_pcidas.c
@@ -346,8 +346,6 @@ struct cb_pcidas_private {
        /* divisors of master clock for analog input pacing */
        unsigned int divisor1;
        unsigned int divisor2;
-       /* number of analog input samples remaining */
-       unsigned int count;
        /* bits to write to registers */
        unsigned int adc_fifo_bits;
        unsigned int s5933_intcsr_bits;
@@ -976,9 +974,6 @@ static int cb_pcidas_ai_cmd(struct comedi_device *dev,
        if (cmd->scan_begin_src == TRIG_TIMER || cmd->convert_src == TRIG_TIMER)
                cb_pcidas_ai_load_counters(dev);
 
-       /*  set number of conversions */
-       if (cmd->stop_src == TRIG_COUNT)
-               devpriv->count = cmd->chanlist_len * cmd->stop_arg;
        /*  enable interrupts */
        spin_lock_irqsave(&dev->spinlock, flags);
        devpriv->adc_fifo_bits |= INTE;
@@ -1352,17 +1347,15 @@ static irqreturn_t cb_pcidas_interrupt(int irq, void *d)
        /*  if fifo half-full */
        if (status & ADHFI) {
                /*  read data */
-               num_samples = half_fifo;
-               if (cmd->stop_src == TRIG_COUNT &&
-                   num_samples > devpriv->count) {
-                       num_samples = devpriv->count;
-               }
+               num_samples = comedi_nsamples_left(s, half_fifo);
                insw(devpriv->adc_fifo + ADCDATA, devpriv->ai_buffer,
                     num_samples);
                comedi_buf_write_samples(s, devpriv->ai_buffer, num_samples);
-               devpriv->count -= num_samples;
-               if (cmd->stop_src == TRIG_COUNT && devpriv->count == 0)
+
+               if (cmd->stop_src == TRIG_COUNT &&
+                   async->scans_done >= cmd->stop_arg)
                        async->events |= COMEDI_CB_EOA;
+
                /*  clear half-full interrupt latch */
                spin_lock_irqsave(&dev->spinlock, flags);
                outw(devpriv->adc_fifo_bits | INT,
@@ -1379,9 +1372,9 @@ static irqreturn_t cb_pcidas_interrupt(int irq, void *d)
                                break;
                        val = inw(devpriv->adc_fifo);
                        comedi_buf_write_samples(s, &val, 1);
+
                        if (cmd->stop_src == TRIG_COUNT &&
-                           --devpriv->count == 0) {
-                               /* end of acquisition */
+                           async->scans_done >= cmd->stop_arg) {
                                async->events |= COMEDI_CB_EOA;
                                break;
                        }