The comedi (*insn_read) functions are supposed to do simple one-shot
reading of an analog input channel. Currently this driver enables
interrupts and uses wait_for_completion_interruptible() to allow the
interrupt routine to let the analog input (*insn_read) know that
the end-of-conversion has occured.
Simplify the function by using the comedi_timeout() helper to check
the aux status register to see when the conversion is finished.
Signed-off-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx>
Cc: Ian Abbott <abbotti@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/staging/comedi/drivers/quatech_daqp_cs.c | 59 +++++++++++-------------
1 file changed, 28 insertions(+), 31 deletions(-)
diff --git a/drivers/staging/comedi/drivers/quatech_daqp_cs.c b/drivers/staging/comedi/drivers/quatech_daqp_cs.c
index de28224..dbb8ffc 100644
--- a/drivers/staging/comedi/drivers/quatech_daqp_cs.c
+++ b/drivers/staging/comedi/drivers/quatech_daqp_cs.c
@@ -48,8 +48,6 @@ Devices: [Quatech] DAQP-208 (daqp), DAQP-308
*/
#include <linux/module.h>
-#include <linux/semaphore.h>
-#include <linux/completion.h>
#include "../comedi_pcmcia.h"
@@ -59,8 +57,6 @@ struct daqp_private {
int stop;
enum { semaphore, buffer } interrupt_mode;
-
- struct completion eos;
};
/* The DAQP communicates with the system through a 16 byte I/O window. */
@@ -175,15 +171,6 @@ static int daqp_ai_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
return 0;
}
-/* Interrupt handler
- *
- * Operates in one of two modes. If devpriv->interrupt_mode is
- * 'semaphore', just signal the devpriv->eos completion and return
- * (one-shot mode). Otherwise (continuous mode), read data in from
- * the card, transfer it to the buffer provided by the higher-level
- * comedi kernel module, and signal various comedi callback routines,
- * which run pretty quick.
- */
static enum irqreturn daqp_interrupt(int irq, void *dev_id)
{
struct comedi_device *dev = dev_id;
@@ -198,7 +185,6 @@ static enum irqreturn daqp_interrupt(int irq, void *dev_id)
switch (devpriv->interrupt_mode) {
case semaphore:
- complete(&devpriv->eos);
break;
case buffer:
@@ -270,15 +256,27 @@ static void daqp_ai_set_scanlist(struct comedi_device *dev,
}
}
-/* One-shot analog data acquisition routine */
+static int daqp_ai_eos(struct comedi_device *dev,
+ struct comedi_subdevice *s,
+ struct comedi_insn *insn,
+ unsigned long context)
+{
+ unsigned int status;
+
+ status = inb(dev->iobase + DAQP_AUX);
+ if (status & DAQP_AUX_CONVERSION)
+ return 0;
+ return -EBUSY;
+}
static int daqp_ai_insn_read(struct comedi_device *dev,
struct comedi_subdevice *s,
- struct comedi_insn *insn, unsigned int *data)
+ struct comedi_insn *insn,
+ unsigned int *data)
{
struct daqp_private *devpriv = dev->private;
+ int ret = 0;
int i;
- int v;
int counter = 10000;
if (devpriv->stop)
@@ -296,12 +294,8 @@ static int daqp_ai_insn_read(struct comedi_device *dev,
outb(DAQP_COMMAND_RSTF, dev->iobase + DAQP_COMMAND);
- /* Set trigger */
-
- v = DAQP_CONTROL_TRIGGER_ONESHOT | DAQP_CONTROL_TRIGGER_INTERNAL
- | DAQP_CONTROL_PACER_100kHz | DAQP_CONTROL_EOS_INT_ENABLE;
-
- outb(v, dev->iobase + DAQP_CONTROL);
+ /* one-shot internal trigger, no pacer, no interrupts */
+ outb(0, dev->iobase + DAQP_CONTROL);
/* Reset any pending interrupts (my card has a tendency to require
* require multiple reads on the status register to achieve this)
@@ -316,25 +310,28 @@ static int daqp_ai_insn_read(struct comedi_device *dev,
return -1;
}
- init_completion(&devpriv->eos);
- devpriv->interrupt_mode = semaphore;
-
for (i = 0; i < insn->n; i++) {
/* Start conversion */
outb(DAQP_COMMAND_ARM | DAQP_COMMAND_FIFO_DATA,
dev->iobase + DAQP_COMMAND);
- /* Wait for interrupt service routine to unblock completion */
- /* Maybe could use a timeout here, but it's interruptible */
- if (wait_for_completion_interruptible(&devpriv->eos))
- return -EINTR;
+ ret = comedi_timeout(dev, s, insn, daqp_ai_eos, 0);
+ if (ret)
+ break;
+
+ /* clear the status event flags */
+ inb(dev->iobase + DAQP_STATUS);
data[i] = inb(dev->iobase + DAQP_FIFO);
data[i] |= inb(dev->iobase + DAQP_FIFO) << 8;
data[i] ^= 0x8000;
}
- return insn->n;
+ /* stop any conversions and clear the status event flags */
+ outb(DAQP_COMMAND_STOP, dev->iobase + DAQP_COMMAND);
+ inb(dev->iobase + DAQP_STATUS);
+
+ return ret ? ret : insn->n;
}
/* This function converts ns nanoseconds to a counter value suitable
--
2.5.1
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