From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Wolfram Sang <wsa@kernel.org>
Cc: "Krzysztof Kozlowski" <krzysztof.kozlowski+dt@linaro.org>,
"Laurent Pinchart" <laurent.pinchart@ideasonboard.com>,
"Geert Uytterhoeven" <geert+renesas@glider.be>,
"Rob Herring" <robh+dt@kernel.org>,
"Conor Dooley" <conor+dt@kernel.org>,
"Andrzej Hajda" <andrzej.hajda@intel.com>,
"Neil Armstrong" <neil.armstrong@linaro.org>,
"Robert Foss" <rfoss@kernel.org>,
"David Airlie" <airlied@gmail.com>,
"Daniel Vetter" <daniel@ffwll.ch>,
"Kieran Bingham" <kieran.bingham@ideasonboard.com>,
"Mauro Carvalho Chehab" <mchehab@kernel.org>,
"Hans Verkuil" <hverkuil-cisco@xs4all.nl>,
"Alessandro Zummo" <a.zummo@towertech.it>,
"Alexandre Belloni" <alexandre.belloni@bootlin.com>,
"Jonas Karlman" <jonas@kwiboo.se>,
"Jernej Skrabec" <jernej.skrabec@gmail.com>,
"Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>,
"Corey Minyard" <cminyard@mvista.com>,
"Marek Behún" <kabel@kernel.org>,
"Jiasheng Jiang" <jiasheng@iscas.ac.cn>,
"Antonio Borneo" <antonio.borneo@foss.st.com>,
"Abhinav Kumar" <quic_abhinavk@quicinc.com>,
"Ahmad Fatoum" <a.fatoum@pengutronix.de>,
"dri-devel@lists.freedesktop.org"
<dri-devel@lists.freedesktop.org>,
"linux-i2c@vger.kernel.org" <linux-i2c@vger.kernel.org>,
"linux-media@vger.kernel.org" <linux-media@vger.kernel.org>,
"Fabrizio Castro" <fabrizio.castro.jz@renesas.com>,
"linux-renesas-soc@vger.kernel.org"
<linux-renesas-soc@vger.kernel.org>,
"Mark Brown" <broonie@kernel.org>
Subject: Re: [PATCH v5 01/11] i2c: Enhance i2c_new_ancillary_device API
Date: Mon, 12 Jun 2023 14:42:19 +0200 [thread overview]
Message-ID: <CAMuHMdV_iwdP+K1us86OB4VtDDqA=P_vNeCP15kqRuXqcYr3hg@mail.gmail.com> (raw)
In-Reply-To: <ZIcRKl3PDy0+yZS9@ninjato>
Hi Wolfram, Laurent,
On Mon, Jun 12, 2023 at 2:36 PM Wolfram Sang <wsa@kernel.org> wrote:
> > DT-Maintainers suggestion:
> > [1]
> > raa215300: pmic@12 {
> > compatible = "renesas,raa215300";
If you go for separate nodes: "renesas,raa215300-pmic".
> > reg = <0x12>, <0x6f>;
> > reg-names = "main", "rtc";
> >
> > clocks = <&x2>;
> > clock-names = "xin";
> > /* Add Optional shared IRQ resource and share it to child and handle it both in parent and child */
> > };
>
> Would this binding allow to not use the RTC if the second reg is
> missing? What are the advantages of not enabling RTC? Saving power?
It doesn't work if there is no clock?
> > Laurent/Wolfram suggestion to split it into two nodes and get rid of this patch:
> > [2]
> > raa215300: pmic @12 {
> > compatible = "renesas,raa215300";
> > reg = <0x12>;
> >
> > /* Add Optional shared IRQ */
> > renesas,raa215300-rtc = <&rtc_raa215300>; /* Parse the handle and Enable RTC , if present.*/
>
> Thinking more about this: DT is hardware description, so the RTC should
> always be described in DT. If the RTC is actually activated is more a
> configuration thing, or? Brainstorming: maybe the PMIC driver could try
> to find the node with reg == 0x6f and see if firmware has enabled it or
> not?
I guess the RTC part would acknowledge anyway?
It is always present, it is just part of the RAA215300.
> > };
> >
> > rtc_raa215300: rtc@6f {
> > compatible = "renesas,raa215300-isl1208";
If you go for separate nodes: "renesas,raa215300-rtc".
> > reg = <0x6f>;
> >
> > /* Add Optional shared IRQ */
> > clocks = <&x2>;
> > clock-names = "xin";
> > renesas,raa215300-pmic = <&pmic>; /* Parse the handle to get PMIC version to check Oscillator bit is inverted or not */
> > };
>
> I have been scratching my head around this and wondered about one thing.
> The RTC driver needs to know if the oscillator bit is inverted. AFAIU
> this depends on the version of the PMIC (which includes the RTC). So,
> can't we simply encode the version in the compatible string?
>
> > compatible = "renesas,raa215300-isl1208-01";
> > compatible = "renesas,raa215300-isl1208-a0";
>
> I dunno the exact versions, but you probably get the idea.
Sure, you can put that in DT. But it's a pity you have to do that,
as the device (the PMIC part) does know the revision...
That's why I suggested to let the PMIC part instantiate an i2c ancillary
device...
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.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
next prev parent reply other threads:[~2023-06-12 12:50 UTC|newest]
Thread overview: 61+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20230522101849.297499-1-biju.das.jz@bp.renesas.com>
2023-05-22 10:18 ` [PATCH v5 01/11] i2c: Enhance i2c_new_ancillary_device API Biju Das
2023-05-23 9:50 ` Hans Verkuil
2023-05-25 16:49 ` Geert Uytterhoeven
2023-05-29 8:05 ` Laurent Pinchart
2023-05-29 9:00 ` Biju Das
2023-05-31 8:59 ` Laurent Pinchart
2023-05-31 9:34 ` Biju Das
2023-05-31 11:41 ` Laurent Pinchart
2023-05-31 12:53 ` Biju Das
2023-05-31 13:35 ` Laurent Pinchart
2023-05-31 13:44 ` Biju Das
2023-06-02 7:40 ` Biju Das
2023-05-31 13:37 ` Geert Uytterhoeven
2023-05-31 13:47 ` Biju Das
2023-05-31 12:51 ` Geert Uytterhoeven
2023-05-31 13:37 ` Laurent Pinchart
2023-05-31 13:39 ` Geert Uytterhoeven
2023-06-05 9:30 ` Wolfram Sang
2023-06-07 8:53 ` Wolfram Sang
2023-06-07 10:58 ` Biju Das
2023-06-08 6:41 ` Biju Das
2023-06-08 10:39 ` Laurent Pinchart
2023-06-08 11:00 ` Biju Das
2023-06-08 12:50 ` Laurent Pinchart
2023-06-08 12:57 ` Biju Das
2023-06-12 9:53 ` Biju Das
2023-06-12 12:23 ` Laurent Pinchart
2023-06-12 12:42 ` Biju Das
2023-06-12 12:54 ` Laurent Pinchart
2023-06-12 13:08 ` Geert Uytterhoeven
2023-06-12 13:19 ` Laurent Pinchart
2023-06-12 12:44 ` Geert Uytterhoeven
2023-06-12 13:02 ` Laurent Pinchart
2023-06-12 12:35 ` Wolfram Sang
2023-06-12 12:42 ` Geert Uytterhoeven [this message]
2023-06-12 12:48 ` Wolfram Sang
2023-06-12 13:00 ` Geert Uytterhoeven
2023-06-12 20:43 ` Wolfram Sang
2023-06-13 7:24 ` Biju Das
2023-06-13 17:57 ` Biju Das
2023-06-13 19:31 ` Biju Das
2023-06-14 8:13 ` Laurent Pinchart
2023-06-14 8:21 ` Biju Das
2023-06-14 9:18 ` Geert Uytterhoeven
2023-06-14 11:04 ` Biju Das
2023-06-15 9:00 ` Geert Uytterhoeven
2023-06-14 9:54 ` Laurent Pinchart
2023-06-14 11:30 ` Biju Das
2023-06-15 9:26 ` Laurent Pinchart
2023-06-20 8:06 ` Biju Das
2023-06-13 7:25 ` Geert Uytterhoeven
2023-06-13 10:45 ` Biju Das
2023-06-13 14:51 ` Geert Uytterhoeven
2023-06-13 16:11 ` Biju Das
2023-06-14 7:53 ` Geert Uytterhoeven
2023-06-14 8:02 ` Biju Das
2023-06-15 8:07 ` Geert Uytterhoeven
2023-06-15 9:23 ` Laurent Pinchart
2023-06-16 6:32 ` Wolfram Sang
2023-06-19 8:17 ` Biju Das
2023-06-12 13:00 ` Biju Das
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='CAMuHMdV_iwdP+K1us86OB4VtDDqA=P_vNeCP15kqRuXqcYr3hg@mail.gmail.com' \
--to=geert@linux-m68k.org \
--cc=a.fatoum@pengutronix.de \
--cc=a.zummo@towertech.it \
--cc=airlied@gmail.com \
--cc=alexandre.belloni@bootlin.com \
--cc=andrzej.hajda@intel.com \
--cc=antonio.borneo@foss.st.com \
--cc=broonie@kernel.org \
--cc=cminyard@mvista.com \
--cc=conor+dt@kernel.org \
--cc=daniel@ffwll.ch \
--cc=dri-devel@lists.freedesktop.org \
--cc=fabrizio.castro.jz@renesas.com \
--cc=geert+renesas@glider.be \
--cc=hverkuil-cisco@xs4all.nl \
--cc=jernej.skrabec@gmail.com \
--cc=jiasheng@iscas.ac.cn \
--cc=jonas@kwiboo.se \
--cc=kabel@kernel.org \
--cc=kieran.bingham@ideasonboard.com \
--cc=krzysztof.kozlowski+dt@linaro.org \
--cc=laurent.pinchart@ideasonboard.com \
--cc=linux-i2c@vger.kernel.org \
--cc=linux-media@vger.kernel.org \
--cc=linux-renesas-soc@vger.kernel.org \
--cc=mchehab@kernel.org \
--cc=neil.armstrong@linaro.org \
--cc=quic_abhinavk@quicinc.com \
--cc=rfoss@kernel.org \
--cc=robh+dt@kernel.org \
--cc=u.kleine-koenig@pengutronix.de \
--cc=wsa@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).