From: Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org>
To: Boris Brezillon
<boris.brezillon-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
Cc: Wolfram Sang <wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org>,
linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
Jonathan Corbet <corbet-T1hC0tSOHrs@public.gmane.org>,
linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
Greg Kroah-Hartman
<gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org>,
Przemyslaw Sroka <psroka-vna1KIf7WgpBDgjK7y7TUQ@public.gmane.org>,
Arkadiusz Golec <agolec-vna1KIf7WgpBDgjK7y7TUQ@public.gmane.org>,
Alan Douglas <adouglas-vna1KIf7WgpBDgjK7y7TUQ@public.gmane.org>,
Bartosz Folta <bfolta-vna1KIf7WgpBDgjK7y7TUQ@public.gmane.org>,
Damian Kos <dkos-vna1KIf7WgpBDgjK7y7TUQ@public.gmane.org>,
Alicja Jurasik-Urbaniak
<alicja-vna1KIf7WgpBDgjK7y7TUQ@public.gmane.org>,
Jan Kotas <jank-vna1KIf7WgpBDgjK7y7TUQ@public.gmane.org>,
Cyprian Wronka <cwronka-vna1KIf7WgpBDgjK7y7TUQ@public.gmane.org>,
Alexandre Belloni
<alexandre.belloni-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>,
Thomas Petazzoni
<thomas.petazzoni-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>,
Nishanth Menon <nm-l0cyMroinI0@public.gmane.org>,
Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>,
Pawel Moll <pawel.moll-5wv7dgnIgG8@public.gmane.org>,
Mark Rutland <mark.rutland-5wv7dgnIgG8@public.gmane.org>,
Ian Campbell
<ijc+devicetree-KcIKpvwj1kUDXYZnReoRVg@public.gmane.org>,
Ku
Subject: Re: [RFC 2/5] i3c: Add core I3C infrastructure
Date: Tue, 1 Aug 2017 22:16:29 +0200 [thread overview]
Message-ID: <CAK8P3a12kUxi1dFPeoMEkDvaoEaV28WiBTvWU+O+m2_CU3W=EQ@mail.gmail.com> (raw)
In-Reply-To: <20170801171434.2bc2aa84@bbrezillon>
On Tue, Aug 1, 2017 at 5:14 PM, Boris Brezillon
<boris.brezillon-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> wrote:
> On Tue, 1 Aug 2017 16:22:21 +0200 Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org> wrote:
>> On Tue, Aug 1, 2017 at 3:58 PM, Boris Brezillon
>> <boris.brezillon-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> wrote:
>> > On Tue, 1 Aug 2017 15:34:14 +0200
>> > Boris Brezillon <boris.brezillon-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> wrote:
>> >> On Tue, 1 Aug 2017 15:11:44 +0200
>> >> Arnd Bergmann <arnd-r2nGTMty4D4@public.gmane.org> wrote:
>> >> > On Tue, Aug 1, 2017 at 2:29 PM, Boris Brezillon
>> >> > <boris.brezillon-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> wrote:
>> > I just realized I forgot to add a "depends on I2C" in the I3C Kconfig
>> > entry. Indeed, I'm unconditionally calling functions provided by the
>> > I2C framework which have no dummy wrapper when I2C support is disabled.
>> > I could of course conditionally compile some portion of the I3C
>> > framework so that it still builds when I2C is disabled but I'm not sure
>> > it's worth the trouble.
>> >
>> > This "depends on I2C" should also solve the I2C+I3C driver issue, since
>> > I2C is necessarily enabled when I3C is.
>> >
>> > Am I missing something?
>>
>> That should solve another part of the problem, as a combined driver then
>> just needs 'depends on I3C'.
>>
>> On top of that, the i3c_driver structure could also contain callback
>> pointers for the i2c subsystem, e.g. i2c_probe(), i2c_remove() etc.
>> When the i2c_probe() callback exists, the i3c layer could construct
>> a 'struct i2c_driver' with those callbacks and register that under the
>> cover. This would mean that combined drivers no longer need to
>> register two driver objects.
>
> That should work. Actually, i2c_driver contains a few more hooks, like
> ->alert(), ->command() and ->detect(). Of course we could assume that
> I3C/I2C drivers do not need them,
I was thinking we can add them as they are needed.
> but I'm wondering if it's not easier
> to just add an i2c_driver pointer inside the i3c_driver struct and let
> the driver populate it if it needs to supports both protocols.
>
> Something like:
>
> struct i3c_driver {
> ...
> struct i2c_driver *i2c_compat;
> ...
> };
>
>
> and then in I3C/I2C drivers:
>
> static struct i2c_driver my_i2c_driver = {
> ...
> };
>
> static struct i3c_driver my_i3c_driver = {
> ...
> .i2c_compat = &my_i2c_driver,
> ...
> };
> module_i3c_driver(my_i3c_driver);
>
>
>
> Of course, you'll have a few fields of ->i2c_compat that would be
> filled by the core (like the driver name which can be extracted from
> my_i3c_driver->driver.name).
Right, that would work too, but it's almost the same as the version
you proposed earlier that would use
module_i2c_i3c_driver(my_i2c_driver, my_i3c_driver);
It's probably a little cleaner this way in the subsystem implementation
compared to my suggestion of adding the i2c callback pointers in
struct i3c_driver, while that would make the drivers look a little nicer
(and save a few lines per driver).
Arnd
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
next prev parent reply other threads:[~2017-08-01 20:16 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-07-31 16:24 [RFC 0/5] Add I3C subsystem Boris Brezillon
2017-07-31 16:24 ` [RFC 1/5] i2c: Export of_i2c_get_board_info() Boris Brezillon
2017-07-31 16:24 ` [RFC 2/5] i3c: Add core I3C infrastructure Boris Brezillon
2017-07-31 19:17 ` Wolfram Sang
2017-07-31 20:46 ` Boris Brezillon
2017-07-31 20:16 ` Arnd Bergmann
[not found] ` <CAK8P3a06GoMdKdn=3Cq0FUwYnjGX0oG+FQLjxfiasVDpbonWRw-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2017-07-31 21:15 ` Boris Brezillon
2017-07-31 21:32 ` Peter Rosin
2017-07-31 21:42 ` Wolfram Sang
2017-08-01 16:47 ` Andrew F. Davis
2017-08-01 17:27 ` Wolfram Sang
2017-08-01 21:47 ` Boris Brezillon
2017-08-02 10:21 ` Wolfram Sang
2017-08-01 12:00 ` Arnd Bergmann
2017-08-01 12:29 ` Boris Brezillon
2017-08-01 13:11 ` Arnd Bergmann
2017-08-01 13:34 ` Boris Brezillon
2017-08-01 13:58 ` Boris Brezillon
2017-08-01 14:22 ` Arnd Bergmann
2017-08-01 15:14 ` Boris Brezillon
2017-08-01 20:16 ` Arnd Bergmann [this message]
2017-08-01 14:12 ` Wolfram Sang
2017-08-01 14:48 ` Boris Brezillon
2017-08-01 15:01 ` Wolfram Sang
2017-08-01 15:20 ` Boris Brezillon
2017-08-03 8:03 ` Boris Brezillon
2017-08-16 21:03 ` Geert Uytterhoeven
2017-08-17 7:48 ` Boris Brezillon
2017-08-01 1:40 ` Greg Kroah-Hartman
[not found] ` <20170801014021.GA20004-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>
2017-08-01 10:48 ` Boris Brezillon
2017-08-01 17:51 ` Greg Kroah-Hartman
2017-08-01 21:30 ` Boris Brezillon
2017-08-02 0:54 ` Greg Kroah-Hartman
2017-08-02 2:13 ` Greg Kroah-Hartman
[not found] ` <20170802021327.GB23033-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org>
2017-12-13 16:20 ` Boris Brezillon
2017-12-13 16:51 ` Greg Kroah-Hartman
2017-08-17 9:03 ` Linus Walleij
2017-08-17 9:28 ` Boris Brezillon
[not found] ` <1501518290-5723-1-git-send-email-boris.brezillon-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>
2017-07-31 16:24 ` [RFC 3/5] dt-bindings: i3c: Document core bindings Boris Brezillon
2017-08-09 23:43 ` Rob Herring
2017-08-10 8:49 ` Boris Brezillon
2017-07-31 16:24 ` [RFC 4/5] i3c: master: Add driver for Cadence IP Boris Brezillon
2017-07-31 16:24 ` [RFC 5/5] dt-bindings: i3c: Document Cadence I3C master bindings Boris Brezillon
2017-07-31 19:17 ` [RFC 0/5] Add I3C subsystem Wolfram Sang
2017-07-31 20:40 ` Boris Brezillon
2017-07-31 20:47 ` Wolfram Sang
2017-12-12 19:58 ` Boris Brezillon
2017-12-12 22:01 ` Wolfram Sang
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='CAK8P3a12kUxi1dFPeoMEkDvaoEaV28WiBTvWU+O+m2_CU3W=EQ@mail.gmail.com' \
--to=arnd-r2ngtmty4d4@public.gmane.org \
--cc=adouglas-vna1KIf7WgpBDgjK7y7TUQ@public.gmane.org \
--cc=agolec-vna1KIf7WgpBDgjK7y7TUQ@public.gmane.org \
--cc=alexandre.belloni-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org \
--cc=alicja-vna1KIf7WgpBDgjK7y7TUQ@public.gmane.org \
--cc=bfolta-vna1KIf7WgpBDgjK7y7TUQ@public.gmane.org \
--cc=boris.brezillon-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org \
--cc=corbet-T1hC0tSOHrs@public.gmane.org \
--cc=cwronka-vna1KIf7WgpBDgjK7y7TUQ@public.gmane.org \
--cc=dkos-vna1KIf7WgpBDgjK7y7TUQ@public.gmane.org \
--cc=gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org \
--cc=ijc+devicetree-KcIKpvwj1kUDXYZnReoRVg@public.gmane.org \
--cc=jank-vna1KIf7WgpBDgjK7y7TUQ@public.gmane.org \
--cc=linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=mark.rutland-5wv7dgnIgG8@public.gmane.org \
--cc=nm-l0cyMroinI0@public.gmane.org \
--cc=pawel.moll-5wv7dgnIgG8@public.gmane.org \
--cc=psroka-vna1KIf7WgpBDgjK7y7TUQ@public.gmane.org \
--cc=robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org \
--cc=thomas.petazzoni-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org \
--cc=wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.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).