lkml.org 
[lkml]   [2023]   [May]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH v5 4/8] pinctrl: wpcm450: relax return value check for IRQ get
Fri, May 19, 2023 at 02:02:16PM +0300, Matti Vaittinen kirjoitti:
> fwnode_irq_get[_byname]() were changed to not return 0 anymore. The
> special error case where device-tree based IRQ mapping fails can't no
> longer be reliably detected from this return value. This yields a
> functional change in the driver where the mapping failure is treated as
> an error.
>
> The mapping failure can occur for example when the device-tree IRQ
> information translation call-back(s) (xlate) fail, IRQ domain is not
> found, IRQ type conflicts, etc. In most cases this indicates an error in
> the device-tree and special handling is not really required.
>
> One more thing to note is that ACPI APIs do not return zero for any
> failures so this special handling did only apply on device-tree based
> systems.
>
> Drop the special (no error, just skip the IRQ) handling for DT mapping
> failures as these can no longer be separated from other errors at driver
> side.

...

> The commit message does not mention if choosing not to abort the probe
> on device-tree mapping failure (as is done on other errors) was chosen
> because: a) Abort would have broken some existing setup. b) Because skipping
> an IRQ on failure is "the right thing to do", or c) because it sounded like
> a way to minimize risk of breaking something.
>
> If the reason is a) - then I'd appreciate receiving some more
> information and a suggestion how to proceed (if possible). If the reason
> is b), then it might be best to just skip the IRQ instead of aborting
> the probe for all errors on IRQ getting. Finally, in case of c), well,
> by acking this change you will now accept the risk :)

No need to repeat this. As I answered the case c) was in my mind when I made
that change.


--
With Best Regards,
Andy Shevchenko


\
 
 \ /
  Last update: 2023-05-21 19:43    [W:0.336 / U:0.064 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site