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From: Saravana Kannan <saravanak@google.com>
Date: Thu, 29 Feb 2024 14:45:10 -0800
Message-ID: <CAGETcx-sZXeSxgtYMvgbR4GEpSo2g7hDH1KshEoqZBHf9C42fw@mail.gmail.com>
Subject: Re: [PATCH] of: property: fw_devlink: Fix stupid bug in
 remote-endpoint parsing
To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Rob Herring <robh+dt@kernel.org>, Frank Rowand <frowand.list@gmail.com>, 
	=?UTF-8?Q?Herv=C3=A9_Codina?= <herve.codina@bootlin.com>, 
	Luca Ceresoli <luca.ceresoli@bootlin.com>, kernel-team@android.com, 
	Rob Herring <robh@kernel.org>, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
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On Thu, Feb 29, 2024 at 2:11=E2=80=AFAM Geert Uytterhoeven <geert@linux-m68=
k.org> wrote:
>
> Hi Saravana,
>
> On Sat, Feb 24, 2024 at 6:25=E2=80=AFAM Saravana Kannan <saravanak@google=
com> wrote:
> > Introduced a stupid bug in commit 782bfd03c3ae ("of: property: Improve
> > finding the supplier of a remote-endpoint property") due to a last minu=
te
> > incorrect edit of "index !=3D0" into "!index". This patch fixes it to b=
e
> > "index > 0" to match the comment right next to it.
> >
> > Reported-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
> > Link: https://lore.kernel.org/lkml/20240223171849.10f9901d@booty/
> > Fixes: 782bfd03c3ae ("of: property: Improve finding the supplier of a r=
emote-endpoint property")
> > Signed-off-by: Saravana Kannan <saravanak@google.com>
>
> Thanks for your patch!
>
> > --- a/drivers/of/property.c
> > +++ b/drivers/of/property.c
> > @@ -1304,7 +1304,7 @@ static struct device_node *parse_remote_endpoint(=
struct device_node *np,
> >                                                  int index)
> >  {
> >         /* Return NULL for index > 0 to signify end of remote-endpoints=
 */
> > -       if (!index || strcmp(prop_name, "remote-endpoint"))
> > +       if (index > 0 || strcmp(prop_name, "remote-endpoint"))
> >                 return NULL;
> >
> >         return of_graph_get_remote_port_parent(np);
> > --
> > 2.44.0.rc0.258.g7320e95886-goog
>
> After this, the "Fixed dependency cycle" messages I reported to be
> gone in [1] are back.
>
> In fact, they are slightly different, and there are now even more of them=
:
>
> -platform fea80000.csi2: Fixed dependency cycle(s) with
> /soc/video@e6ef7000/ports/port@1/endpoint@0
> -platform fea80000.csi2: Fixed dependency cycle(s) with
> /soc/video@e6ef6000/ports/port@1/endpoint@0
> -platform fea80000.csi2: Fixed dependency cycle(s) with
> /soc/video@e6ef5000/ports/port@1/endpoint@0
> -platform fea80000.csi2: Fixed dependency cycle(s) with
> /soc/video@e6ef4000/ports/port@1/endpoint@0
> -platform fea80000.csi2: Fixed dependency cycle(s) with
> /soc/video@e6ef3000/ports/port@1/endpoint@0
> -platform fea80000.csi2: Fixed dependency cycle(s) with
> /soc/video@e6ef2000/ports/port@1/endpoint@0
> -platform fea80000.csi2: Fixed dependency cycle(s) with
> /soc/video@e6ef1000/ports/port@1/endpoint@0
> -platform fea80000.csi2: Fixed dependency cycle(s) with
> /soc/video@e6ef0000/ports/port@1/endpoint@0
> -platform feaa0000.csi2: Fixed dependency cycle(s) with
> /soc/video@e6ef3000/ports/port@1/endpoint@2
> -platform feaa0000.csi2: Fixed dependency cycle(s) with
> /soc/video@e6ef2000/ports/port@1/endpoint@2
> -platform feaa0000.csi2: Fixed dependency cycle(s) with
> /soc/video@e6ef1000/ports/port@1/endpoint@2
> -platform feaa0000.csi2: Fixed dependency cycle(s) with
> /soc/video@e6ef0000/ports/port@1/endpoint@2
> -platform fead0000.hdmi: Fixed dependency cycle(s) with
> /soc/sound@ec500000/ports/port@1/endpoint
> -platform feae0000.hdmi: Fixed dependency cycle(s) with
> /soc/sound@ec500000/ports/port@2/endpoint
> -platform feb00000.display: Fixed dependency cycle(s) with
> /soc/hdmi@feae0000/ports/port@0/endpoint
> -platform feb00000.display: Fixed dependency cycle(s) with
> /soc/hdmi@fead0000/ports/port@0/endpoint
> -platform hdmi0-out: Fixed dependency cycle(s) with
> /soc/hdmi@fead0000/ports/port@1/endpoint
> -platform hdmi1-out: Fixed dependency cycle(s) with
> /soc/hdmi@feae0000/ports/port@1/endpoint
> -platform vga-encoder: Fixed dependency cycle(s) with /vga/port/endpoint
> -platform vga-encoder: Fixed dependency cycle(s) with
> /soc/display@feb00000/ports/port@0/endpoint
> +platform e6ef0000.video: Fixed dependency cycle(s) with /soc/csi2@feaa00=
00
> +platform e6ef0000.video: Fixed dependency cycle(s) with /soc/csi2@fea800=
00
> +platform e6ef1000.video: Fixed dependency cycle(s) with /soc/csi2@feaa00=
00
> +platform e6ef1000.video: Fixed dependency cycle(s) with /soc/csi2@fea800=
00
> +platform e6ef2000.video: Fixed dependency cycle(s) with /soc/csi2@feaa00=
00
> +platform e6ef2000.video: Fixed dependency cycle(s) with /soc/csi2@fea800=
00
> +platform e6ef3000.video: Fixed dependency cycle(s) with /soc/csi2@feaa00=
00
> +platform e6ef3000.video: Fixed dependency cycle(s) with /soc/csi2@fea800=
00
> +platform e6ef4000.video: Fixed dependency cycle(s) with /soc/csi2@fea800=
00
> +platform e6ef5000.video: Fixed dependency cycle(s) with /soc/csi2@fea800=
00
> +platform e6ef6000.video: Fixed dependency cycle(s) with /soc/csi2@fea800=
00
> +platform e6ef7000.video: Fixed dependency cycle(s) with /soc/csi2@fea800=
00
> +platform ec500000.sound: Fixed dependency cycle(s) with /soc/hdmi@feae00=
00
> +platform ec500000.sound: Fixed dependency cycle(s) with /soc/hdmi@fead00=
00
> +platform ec500000.sound: Fixed dependency cycle(s) with
> /soc/i2c@e6510000/codec@10
> +platform e6ef7000.video: Fixed dependency cycle(s) with /soc/csi2@fea800=
00
> +platform e6ef6000.video: Fixed dependency cycle(s) with /soc/csi2@fea800=
00
> +platform e6ef5000.video: Fixed dependency cycle(s) with /soc/csi2@fea800=
00
> +platform e6ef4000.video: Fixed dependency cycle(s) with /soc/csi2@fea800=
00
> +platform e6ef3000.video: Fixed dependency cycle(s) with /soc/csi2@fea800=
00
> +platform e6ef2000.video: Fixed dependency cycle(s) with /soc/csi2@fea800=
00
> +platform e6ef1000.video: Fixed dependency cycle(s) with /soc/csi2@fea800=
00
> +platform e6ef0000.video: Fixed dependency cycle(s) with /soc/csi2@fea800=
00
> +platform fea80000.csi2: Fixed dependency cycle(s) with /soc/video@e6ef70=
00
> +platform fea80000.csi2: Fixed dependency cycle(s) with /soc/video@e6ef60=
00
> +platform fea80000.csi2: Fixed dependency cycle(s) with /soc/video@e6ef50=
00
> +platform fea80000.csi2: Fixed dependency cycle(s) with /soc/video@e6ef40=
00
> +platform fea80000.csi2: Fixed dependency cycle(s) with /soc/video@e6ef30=
00
> +platform fea80000.csi2: Fixed dependency cycle(s) with /soc/video@e6ef20=
00
> +platform fea80000.csi2: Fixed dependency cycle(s) with /soc/video@e6ef10=
00
> +platform fea80000.csi2: Fixed dependency cycle(s) with /soc/video@e6ef00=
00
> +platform fea80000.csi2: Fixed dependency cycle(s) with
> /soc/i2c@e66d8000/video-receiver@70
> +platform e6ef3000.video: Fixed dependency cycle(s) with /soc/csi2@feaa00=
00
> +platform e6ef2000.video: Fixed dependency cycle(s) with /soc/csi2@feaa00=
00
> +platform e6ef1000.video: Fixed dependency cycle(s) with /soc/csi2@feaa00=
00
> +platform e6ef0000.video: Fixed dependency cycle(s) with /soc/csi2@feaa00=
00
> +platform feaa0000.csi2: Fixed dependency cycle(s) with /soc/video@e6ef30=
00
> +platform feaa0000.csi2: Fixed dependency cycle(s) with /soc/video@e6ef20=
00
> +platform feaa0000.csi2: Fixed dependency cycle(s) with /soc/video@e6ef10=
00
> +platform feaa0000.csi2: Fixed dependency cycle(s) with /soc/video@e6ef00=
00
> +platform feaa0000.csi2: Fixed dependency cycle(s) with
> /soc/i2c@e66d8000/video-receiver@70
> +platform ec500000.sound: Fixed dependency cycle(s) with /soc/hdmi@fead00=
00
> +platform fead0000.hdmi: Fixed dependency cycle(s) with /soc/sound@ec5000=
00
> +platform fead0000.hdmi: Fixed dependency cycle(s) with /soc/display@feb0=
0000
> +platform ec500000.sound: Fixed dependency cycle(s) with /soc/hdmi@feae00=
00
> +platform feae0000.hdmi: Fixed dependency cycle(s) with /soc/sound@ec5000=
00
> +platform feae0000.hdmi: Fixed dependency cycle(s) with /soc/display@feb0=
0000
> +platform feae0000.hdmi: Fixed dependency cycle(s) with /soc/display@feb0=
0000
> +platform fead0000.hdmi: Fixed dependency cycle(s) with /soc/display@feb0=
0000
> +platform feb00000.display: Fixed dependency cycle(s) with /soc/hdmi@feae=
0000
> +platform feb00000.display: Fixed dependency cycle(s) with /soc/hdmi@fead=
0000
> +platform cvbs-in: Fixed dependency cycle(s) with
> /soc/i2c@e66d8000/video-receiver@70
> +platform hdmi-in: Fixed dependency cycle(s) with
> /soc/i2c@e66d8000/video-receiver@70
> +platform fead0000.hdmi: Fixed dependency cycle(s) with /hdmi0-out
> +platform hdmi0-out: Fixed dependency cycle(s) with /soc/hdmi@fead0000
> +platform feae0000.hdmi: Fixed dependency cycle(s) with /hdmi1-out
> +platform hdmi1-out: Fixed dependency cycle(s) with /soc/hdmi@feae0000
> +platform vga: Fixed dependency cycle(s) with /vga-encoder
> +platform feb00000.display: Fixed dependency cycle(s) with /vga-encoder
> +platform vga-encoder: Fixed dependency cycle(s) with /vga
> +platform vga-encoder: Fixed dependency cycle(s) with /soc/display@feb000=
00
>
> -i2c 2-0010: Fixed dependency cycle(s) with
> /soc/sound@ec500000/ports/port@0/endpoint
> +platform ec500000.sound: Fixed dependency cycle(s) with
> /soc/i2c@e6510000/codec@10
>
> -i2c 4-0070: Fixed dependency cycle(s) with
> /soc/csi2@fea80000/ports/port@0/endpoint
> -i2c 4-0070: Fixed dependency cycle(s) with
> /soc/csi2@feaa0000/ports/port@0/endpoint
> -i2c 4-0070: Fixed dependency cycle(s) with /hdmi-in/port/endpoint
> -i2c 4-0070: Fixed dependency cycle(s) with /cvbs-in/port/endpoint
> +platform feaa0000.csi2: Fixed dependency cycle(s) with
> /soc/i2c@e66d8000/video-receiver@70
> +platform fea80000.csi2: Fixed dependency cycle(s) with
> /soc/i2c@e66d8000/video-receiver@70
> +i2c 4-0070: Fixed dependency cycle(s) with /soc/csi2@fea80000
> +i2c 4-0070: Fixed dependency cycle(s) with /soc/csi2@feaa0000
>
> I guess all of that is expected?

I'm assuming all of these cycles are between devices that use
remote-endpoint/port(s)? If so, yes, these are all expected. It's just
logging things more accurately now.

Once post-init-providers lands, you can use that property to break the
cycles and also allow a better probe/suspend/resume ordering between
these devices.

-Saravana

> [1] https://lore.kernel.org/all/CAMuHMdVon3mdivZQ0O6D4+va0nGBrUQbDp23bEq6=
61QD=3D4t7+g@mail.gmail.com/
>
> Gr{oetje,eeting}s,
>
>                         Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m6=
8k.org
>
> In personal conversations with technical people, I call myself a hacker. =
But
> when I'm talking to journalists I just say "programmer" or something like=
 that.
>                                 -- Linus Torvalds