[PATCH v4] staging: comedi: Improved readability of function comedi_nsamples_left.

From: Chris Opperman
Date: Tue Jun 12 2018 - 15:12:02 EST


Changes since v3:
a) Reverted u64 to unsigned long long and u32 to unsigned int.
b) Added patch versioning.
c) Changed type of scans_left to unsigned long long to avoid cast.
d) Clarified and updated changelog.

>8-----------------------------------------------------------------------8<

Improve readability of comedi_nsamples_left:
a) Reduce nesting by using more return statements.
b) Declare variables scans_left and samples_left at start of function.
c) Change type of scans_Left to unsigned long long to avoid cast.

Signed-off-by: Chris Opperman <eklikeroomys@xxxxxxxxx>
---
drivers/staging/comedi/drivers.c | 26 +++++++++++++-------------
1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/drivers/staging/comedi/drivers.c b/drivers/staging/comedi/drivers.c
index 9d73347..57dd63d 100644
--- a/drivers/staging/comedi/drivers.c
+++ b/drivers/staging/comedi/drivers.c
@@ -473,21 +473,21 @@ unsigned int comedi_nsamples_left(struct comedi_subdevice *s,
{
struct comedi_async *async = s->async;
struct comedi_cmd *cmd = &async->cmd;
+ unsigned long long scans_left;
+ unsigned long long samples_left;

- if (cmd->stop_src == TRIG_COUNT) {
- unsigned int scans_left = __comedi_nscans_left(s, cmd->stop_arg);
- unsigned int scan_pos =
- comedi_bytes_to_samples(s, async->scan_progress);
- unsigned long long samples_left = 0;
-
- if (scans_left) {
- samples_left = ((unsigned long long)scans_left *
- cmd->scan_end_arg) - scan_pos;
- }
+ if (cmd->stop_src != TRIG_COUNT)
+ return nsamples;

- if (samples_left < nsamples)
- nsamples = samples_left;
- }
+ scans_left = __comedi_nscans_left(s, cmd->stop_arg);
+ if (!scans_left)
+ return 0;
+
+ samples_left = scans_left * cmd->scan_end_arg -
+ comedi_bytes_to_samples(s, async->scan_progress);
+
+ if (samples_left < nsamples)
+ return samples_left;
return nsamples;
}
EXPORT_SYMBOL_GPL(comedi_nsamples_left);
--
2.1.4