DECLARE_WAITQUEUE(wait, current);
const unsigned minor = iminor(file->f_dentry->d_inode);
struct comedi_file_info *info = comedi_file_info_from_minor(minor);
- struct comedi_device *dev;
+ struct comedi_device *dev = comedi_dev_from_minor(minor);
- if (info == NULL)
- return -ENODEV;
- dev = info->device;
- if (dev == NULL)
+ if (!dev)
return -ENODEV;
if (!dev->attached) {
DPRINTK("no driver configured on comedi%i\n", dev->minor);
- retval = -ENODEV;
- goto done;
+ return -ENODEV;
}
s = comedi_write_subdevice(info);
- if (s == NULL) {
- retval = -EIO;
- goto done;
- }
+ if (!s)
+ return -EIO;
+
async = s->async;
- if (!nbytes) {
- retval = 0;
- goto done;
- }
- if (!s->busy) {
- retval = 0;
- goto done;
- }
- if (s->busy != file) {
- retval = -EACCES;
- goto done;
- }
+ if (!s->busy || !nbytes)
+ return 0;
+ if (s->busy != file)
+ return -EACCES;
+
add_wait_queue(&async->wait_head, &wait);
while (nbytes > 0 && !retval) {
set_current_state(TASK_INTERRUPTIBLE);
set_current_state(TASK_RUNNING);
remove_wait_queue(&async->wait_head, &wait);
-done:
return count ? count : retval;
}