diff --git a/drivers/staging/comedi/comedi_buf.c b/drivers/staging/comedi/comedi_buf.c index eb3fecf85b6d..19e7b229d15e 100644 --- a/drivers/staging/comedi/comedi_buf.c +++ b/drivers/staging/comedi/comedi_buf.c @@ -236,6 +236,7 @@ void comedi_buf_reset(struct comedi_subdevice *s) async->buf_read_ptr = 0; async->cur_chan = 0; + async->scans_done = 0; async->scan_progress = 0; async->munge_chan = 0; async->munge_count = 0; diff --git a/drivers/staging/comedi/comedidev.h b/drivers/staging/comedi/comedidev.h index 90af11aaef7e..bff5a581a287 100644 --- a/drivers/staging/comedi/comedidev.h +++ b/drivers/staging/comedi/comedidev.h @@ -121,6 +121,7 @@ struct comedi_buf_map { * @buf_read_ptr: buffer position for reader * @cur_chan: current position in chanlist for scan (for those * drivers that use it) + * @scans_done: the number of scans completed (COMEDI_CB_EOS) * @scan_progress: amount received or sent for current scan (in bytes) * @munge_chan: current position in chanlist for "munging" * @munge_count: "munge" count (in bytes, modulo 2**32) @@ -201,6 +202,7 @@ struct comedi_async { unsigned int buf_write_ptr; unsigned int buf_read_ptr; unsigned int cur_chan; + unsigned int scans_done; unsigned int scan_progress; unsigned int munge_chan; unsigned int munge_count; diff --git a/drivers/staging/comedi/drivers.c b/drivers/staging/comedi/drivers.c index 9a8c5fc8e8fe..02a01baf5cc6 100644 --- a/drivers/staging/comedi/drivers.c +++ b/drivers/staging/comedi/drivers.c @@ -352,6 +352,13 @@ void comedi_inc_scan_progress(struct comedi_subdevice *s, async->scan_progress += num_bytes; if (async->scan_progress >= scan_length) { + unsigned int nscans = async->scan_progress / scan_length; + + if (async->scans_done < (UINT_MAX - nscans)) + async->scans_done += nscans; + else + async->scans_done = UINT_MAX; + async->scan_progress %= scan_length; async->events |= COMEDI_CB_EOS; }