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staging: comedi: adv_pci1724: use comedi_timeout() to wait for DAC idle state

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Use the comedi_timeout() helper to wait for the DAC to be idle before
writing to it.

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>
This commit is contained in:
H Hartley Sweeten 2014-11-20 15:10:49 -07:00 committed by Greg Kroah-Hartman
parent dcbd4ed87c
commit e25e22b012
1 changed files with 13 additions and 20 deletions
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33
drivers/staging/comedi/drivers/adv_pci1724.c
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@ -53,7 +53,6 @@ supported PCI devices are configured as comedi devices automatically.
*/
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/pci.h>
#include "../comedidev.h"
@ -123,34 +122,24 @@ static const struct comedi_lrange ao_ranges_1724 = {
}
};
static int wait_for_dac_idle(struct comedi_device *dev)
static int adv_pci1724_dac_idle(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_insn *insn,
unsigned long context)
{
static const int timeout = 10000;
int i;
unsigned int status;
for (i = 0; i < timeout; ++i) {
if ((inl(dev->iobase + SYNC_OUTPUT_REG) & DAC_BUSY) == 0)
break;
udelay(1);
}
if (i == timeout) {
dev_err(dev->class_dev,
"Timed out waiting for dac to become idle\n");
return -EIO;
}
return 0;
status = inl(dev->iobase + SYNC_OUTPUT_REG);
if ((status & DAC_BUSY) == 0)
return 0;
return -EBUSY;
}
static int set_dac(struct comedi_device *dev, unsigned mode, unsigned channel,
unsigned data)
{
int retval;
unsigned control_bits;
retval = wait_for_dac_idle(dev);
if (retval < 0)
return retval;
control_bits = mode;
control_bits |= dac_channel_and_group_select_bits(channel);
control_bits |= dac_data_bits(data);
@ -174,6 +163,10 @@ static int adv_pci1724_insn_write(struct comedi_device *dev,
for (i = 0; i < insn->n; ++i) {
unsigned int val = data[i];
ret = comedi_timeout(dev, s, insn, adv_pci1724_dac_idle, 0);
if (ret)
return ret;
ret = set_dac(dev, mode, chan, val);
if (ret < 0)
return ret;