lkml.org 
[lkml]   [2016]   [Dec]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v3] dt-bindings: power: supply: bq24735: reverse the polarity of ac-detect
From
Date
On 12/15/2016 05:21 AM, Peter Rosin wrote:
> The ACOK pin on the bq24735 is active-high, of course meaning that when
> AC is OK the pin is high. However, all Tegra dts files have incorrectly
> specified active-high even though the signal is inverted on the Tegra
> boards. This has worked since the Linux driver has also inverted the
> meaning of the GPIO. Fix this situation by simply specifying in the
> bindings what everybody else agrees on; that the ti,ac-detect-gpios is
> active on AC adapter absence.
>
> Signed-off-by: Peter Rosin <peda@axentia.se>
> ---
>
> Hi!
>
> This patch is the result of this discussion:
> http://marc.info/?t=148152531800002
>
> I don't like how it changes the one thing that is seems correct, but
> what to do?

I haven't followed this thread so hopefully what I say is relevant. My
take is:

If the DT binding is correct or reasonable, keep it.

If the Tegra DTs contain incorrect content, and never worked correctly
in this aspect, then fix them. We do need to maintain DT
ABI/compatibility, but I believe only with stuff that actually worked
correctly. If the DT has a bug, just fix it.

That said, if ti,ac-detect-gpios is describing a host GPIO, then it's
entirely arbitrary which polarity it should have, i.e. the polarity is
not something specified by the bq24735 HW. In that case, feel free to
change either the binding to match the DT or the DT to match the
binding. Changing the DT to match the binding might still be better
since there could be other users you're not aware of, and they might
have written their DT correctly, and you don't want to break them.

\
 
 \ /
  Last update: 2016-12-15 18:33    [W:0.093 / U:0.204 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site