Messages in this thread |  | | | Date | Fri, 6 Mar 2009 15:00:56 -0800 | | From | Andrew Morton <> | | Subject | Re: [PATCH 04/18] Blackfin Serial Driver: Change hardware flowcontrol from poll to interrupt driven. |
| |
On Fri, 6 Mar 2009 17:49:13 -0500 Mike Frysinger <vapier.adi@gmail.com> wrote:
> On Fri, Mar 6, 2009 at 17:38, Andrew Morton wrote: > > On Fri, __6 Mar 2009 14:42:46 +0800 Bryan Wu wrote: > >> From: Sonic Zhang <sonic.zhang@analog.com> > >> > >> Only CTS bit is affected. > >> > >> Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> > >> Signed-off-by: Bryan Wu <cooloney@kernel.org> > > > > Another completely useless changelog. > > the summary, while brief, describes the change: the flowcontrol is > currently implemented by polling, but this changes it to an interrupt > based system
yes, but it doesn't explain why the change was made.
> > Your [PATCH 00/18] email described all these patches as > > needed-in-2.6.29 bugfixes. __As far as I can tell (based on almost zero > > information), this patch is not a bugfix. > > because the current implementation is polling (busy waiting), the > kernel will basically hang when the remote asserts hardware > flowcontrol pins. if this is only asserted for short periods (less > than 1 char time), then it's not really noticed ... but it still > destroys latencies.
That.
Please send through replacement changelogs for all the patches which I complained about. Then I'll pick through it all and see what we can do about a 2.6.29 merge.
|  |