fixed bug with dma transfers not being quite the length I wanted them

to be.

diff --git a/comedi/drivers/das1800.c b/comedi/drivers/das1800.c
index 929949eedc4e4684335b83aca30efe69fb91b5f9..38e2af2ef26fdefa03ae6ff8acbb2252a2a12374 100644 (file)
--- a/comedi/drivers/das1800.c
+++ b/comedi/drivers/das1800.c
@@ -169,6 +169,7 @@ TODO:
 #define   OVF                     0x10
 #define   FHF                     0x20
 #define   FNE                     0x40
+#define   CVEN_MASK               0x40
 #define   CVEN                    0x80
 #define DAS1800_BURST_LENGTH    0x8
 #define DAS1800_BURST_RATE      0x9
@@ -884,7 +885,7 @@ static int das1800_ai_poll(comedi_device *dev,comedi_subdevice *s)
 static void das1800_interrupt(int irq, void *d, struct pt_regs *regs)
 {
        comedi_device *dev = d;
-       int status;
+       unsigned int status;
 
        if(dev->attached == 0)
        {
@@ -897,18 +898,15 @@ static void das1800_interrupt(int irq, void *d, struct pt_regs *regs)
        spin_lock(&dev->spinlock);
        status = inb(dev->iobase + DAS1800_STATUS);
 
-       /* clear interrupt */
-       outb(FNE, dev->iobase + DAS1800_STATUS);
-
        /* if interrupt was not caused by das-1800 */
        if(!(status & INT))
        {
-               comedi_error(dev, "spurious interrupt");
-               rt_printk("status 0x%x\n", status);
                spin_unlock(&dev->spinlock);
                return;
        }
-
+       /* clear the interrupt status bits */
+       outb(CVEN_MASK, dev->iobase + DAS1800_STATUS);
+       // handle interrupt
        das1800_ai_handler(dev, status);
 
        spin_unlock(&dev->spinlock);
@@ -1446,7 +1444,6 @@ static void setup_dma(comedi_device *dev, comedi_cmd cmd)
 
        /* determine a reasonable dma transfer size */
        devpriv->dma_transfer_size = suggest_transfer_size(&cmd);
-
        lock_flags = claim_dma_lock();
        disable_dma(devpriv->dma0);
        /* clear flip-flop to make sure 2-byte registers for
@@ -1748,10 +1745,10 @@ static unsigned int suggest_transfer_size(comedi_cmd *cmd)
        {
                case TRIG_FOLLOW:       // not in burst mode
                        if(cmd->convert_src == TRIG_TIMER)
-                               size = fill_time / cmd->convert_arg;
+                               size = (fill_time / cmd->convert_arg) * sample_size;
                        break;
                case TRIG_TIMER:
-                       size = fill_time / (cmd->scan_begin_arg * cmd->chanlist_len);
+                       size = (fill_time / (cmd->scan_begin_arg * cmd->chanlist_len)) * sample_size;
                        break;
                default:
                        size = DMA_BUF_SIZE;
@@ -1762,11 +1759,11 @@ static unsigned int suggest_transfer_size(comedi_cmd *cmd)
        max_size = DMA_BUF_SIZE;
        // if we are taking limited number of conversions, limit transfer size to that
        if(cmd->stop_src == TRIG_COUNT &&
-               cmd->stop_arg * cmd->chanlist_len < max_size)
-               max_size = cmd->stop_arg * cmd->chanlist_len;
+               cmd->stop_arg * cmd->chanlist_len * sample_size < max_size)
+               max_size = cmd->stop_arg * cmd->chanlist_len * sample_size;
 
        if(size > max_size)
-               size = max_size - max_size % sample_size;
+               size = max_size;
        if(size < sample_size)
                size = sample_size;