lkml.org 
[lkml]   [2022]   [Jun]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH 4/4] serial: 8250_dw: Rework ->serial_out() LCR write retry logic
On Wed, Jun 29, 2022 at 10:47 AM Ilpo Järvinen
<ilpo.jarvinen@linux.intel.com> wrote:
> On Tue, 28 Jun 2022, Andy Shevchenko wrote:
> > On Tue, Jun 28, 2022 at 3:43 PM Ilpo Järvinen
> > <ilpo.jarvinen@linux.intel.com> wrote:
> > >
> > > Currently dw8250_verify_write() (was dw8250_check_lcr()) nullifies the
> > > benefit from differentiated ->serial_out() by having big if tree to
> > > select correct write type.
> > >
> > > Rework the logic such that the LCR write can be retried within the
> > > relevant ->serial_out() handler:
> > > 1. Move retries counter on the caller level and pass as pointer to
> > > dw8250_verify_write()
> > > 2. Make dw8250_verify_write() return bool
> > > 3. Retry the write on caller level (if needed)
> >
> > I'm wondering if it's possible to utilize one of iopoll.h macro here
> > instead of copying retries and that not-so-obvious IO poll write.
>
> Eh, are you suggesting I should do write as a side-effect inside one of
> the iopoll.h macros? Because those available seem to only read?
>
> Or should I create another macro there which writes too?

It seems to me that it would be a macro on top of iopoll's one which
will take an op read and op write arguments depending on the case.
Note, for that special case you would need a custom write op instead
of simple __raw_writeq().

Try and if it looks better, convert, otherwise it would be nice to
hear why it won't fly in your opinion.

--
With Best Regards,
Andy Shevchenko

\
 
 \ /
  Last update: 2022-06-29 11:36    [W:0.056 / U:0.112 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site