[PATCH v4] Staging: comedi: convert while loop to timeout in ni_mio_common.c

[Hartley Sweeten]

On Tuesday, January 14, 2014 8:59 PM, Greg KH wrote:
> Sleep for at least 10, as I think that's the smallest time delay you can
> sleep for anyway (meaning it will be that long no matter what number you
> put there less than 10, depending on the hardware used of course.)

A bit off topic here but I have a somewhat related question about timeouts.

There are a number of comedi drivers that do a "wait for end-of-conversion"
as part of the (*insn_read) for an analog input subdevice or (*insn_write) for
an analog output subdevice. These functions return an errno if a timeout occurs.

Currently either -ETIME or -ETIMEDOUT is returned. This errno ends up getting
returned to the user as the result of the unlocked_ioctl file operation. What is
the more appropriate errno? Or is there is better one that should be used?

Regards,
Hartley