From: Sergio Paracuellos <sergio.paracuellos@gmail.com>
To: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: "open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
"Bartosz Golaszewski" <bgolaszewski@baylibre.com>,
"Matthias Brugger" <matthias.bgg@gmail.com>,
"Linus Walleij" <linus.walleij@linaro.org>,
"John Thomson" <git@johnthomson.fastmail.com.au>,
"Linux Kernel Mailing List" <linux-kernel@vger.kernel.org>,
NeilBrown <neil@brown.name>,
"René van Dorst" <opensource@vdorst.com>,
"Nicholas Mc Guire" <hofrat@osadl.org>
Subject: Re: [PATCH v2] gpio: mt7621: support gpio-line-names property
Date: Sun, 27 Jun 2021 15:12:50 +0200 [thread overview]
Message-ID: <CAMhs-H9gw63j98vVo3y0ymW4_6rFNL8u5cYNM2hzyrmkPB3h3w@mail.gmail.com> (raw)
In-Reply-To: <CAHp75VcF-HDZ6mKvXT=zYnBrcPaNJ+SYJ72LQ7s-62zQ5ZqoQg@mail.gmail.com>
Hi Andy,
On Sun, Jun 27, 2021 at 3:01 PM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
>
> On Sun, Jun 27, 2021 at 1:56 PM Sergio Paracuellos
> <sergio.paracuellos@gmail.com> wrote:
> > On Sun, Jun 27, 2021 at 12:51 PM Andy Shevchenko
> > <andy.shevchenko@gmail.com> wrote:
> > > On Sun, Jun 27, 2021 at 12:47 PM Sergio Paracuellos
> > > <sergio.paracuellos@gmail.com> wrote:
> > > > On Sun, Jun 27, 2021 at 11:33 AM Andy Shevchenko
> > > > <andy.shevchenko@gmail.com> wrote:
> > > > > On Sat, Jun 26, 2021 at 7:18 PM Sergio Paracuellos
> > > > > <sergio.paracuellos@gmail.com> wrote:
> > > > > >
> > > > > > The default handling of the gpio-line-names property by the
> > > > > > gpiolib-of implementation does not work with the multiple
> > > > > > gpiochip banks per device structure used by the gpio-mt7621
> > > > > > driver.
> > > > > >
> > > > > > This commit adds driver level support for the device tree
> > > > > > property so that GPIO lines can be assigned friendly names.
> > >
> > > > > > This driver has three gpiochips with 32 gpios each. Core implementation
> > > > >
> > > > > implementation
> > > > >
> > > > >
> > > > > > got gpio's repeated along each gpio chip if chip.names is not assigned.
> > > > > > To avoid this behaviour driver will set this names as empty or
> > > > >
> > > > > the driver
> > > > > these names
> > > > >
> > > > > > with desired friendly line names. Consider the following sample with
> > > > > > minimal entries for the first chip with this patch changes applied:
> > > > >
> > > > > The same comment as per v1:
> > > > >
> > > > > Any idea why it's not a duplicate of
> > > > > https://elixir.bootlin.com/linux/v5.13-rc7/C/ident/devprop_gpiochip_set_names,
> > > > > and why the latter is not called in your case?
> > > >
> > > > The core properly calls this function but not in the way expected.
> > > > This driver implements three banks of 32 gpios each internally using
> > > > one gpiochip per bank, all of them in the same device. So the core
> > > > code you are pointing out here duplicates the same names along the
> > > > three gpiochips which is not the expected behaviour. So implementing
> > > > in this way and setting names at least reserved avoids the core code
> > > > to be run and also avoids the duplication getting expected behaviour
> > > > for all the banks and each line friendly name.
> > >
> > > Isn't it the problem of how we supply fwnode in that case?
> > > Another possibility is to fix DT (although I'm not sure it's now possible).
> >
> > Since the fwnode is the same for all banks of the same device, each bank
> > repeats the first MTK_BANK_WIDTH label names in each bank.
>
> Can you point out the DT in question?
https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git/tree/drivers/staging/mt7621-dts/mt7621.dtsi?h=staging-next
Gpio node:
gpio: gpio@600 {
#gpio-cells = <2>;
#interrupt-cells = <2>;
compatible = "mediatek,mt7621-gpio";
gpio-controller;
gpio-ranges = <&pinctrl 0 0 95>;
interrupt-controller;
reg = <0x600 0x100>;
interrupt-parent = <&gic>;
interrupts = <GIC_SHARED 12 IRQ_TYPE_LEVEL_HIGH>;
};
My overlay:
&gpio {
gpio-line-names = "", "", "", "",
"", "", "SFP LOS", "extcon port5 PoE compat",
"SFP module def0", "LED blue SFP", "SFP tx disable", "",
"switch USB power", "mode", "", "buzzer",
"LED blue pwr", "switch port5 PoE out", "reset";
};
>
> > This commit populates the gc.names member of each bank from the
> > device-tree node within the driver. This overrides the default behavior
> > since devprop_gpiochip_set_names() will only be called if names is NULL.
>
> I believe this commit is not needed in the proposed (i.e. duplication) shape.
> The fwnode supports primary and secondary ones. Thus, we may create a
> pair of fwnodes when they will unify properties per device with
> properties per child together (child is primary and device, i.e.
> parent, is secondary).
There are no child nodes, all the stuff is in the same parent node
and, as I said, belongs to the same device but internally uses three
gpiochips. This case is pretty much the same as the following already
added commit for gpio-brcmstb:
https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git/commit/drivers/gpio/gpio-brcmstb.c?id=5eefcaed501dd9e3933dbff58720244bd75ed90f
Best regards,
Sergio Paracuellos
>
> --
> With Best Regards,
> Andy Shevchenko
next prev parent reply other threads:[~2021-06-27 13:13 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-26 16:18 [PATCH v2] gpio: mt7621: support gpio-line-names property Sergio Paracuellos
2021-06-27 9:33 ` Andy Shevchenko
2021-06-27 9:47 ` Sergio Paracuellos
2021-06-27 10:51 ` Andy Shevchenko
2021-06-27 10:56 ` Sergio Paracuellos
2021-06-27 13:00 ` Andy Shevchenko
2021-06-27 13:12 ` Sergio Paracuellos [this message]
2021-07-02 9:26 ` Andy Shevchenko
2021-07-02 9:40 ` Sergio Paracuellos
2021-07-02 9:56 ` Andy Shevchenko
2021-07-02 10:18 ` Linus Walleij
2021-07-02 11:30 ` Sergio Paracuellos
2021-07-03 11:06 ` Sergio Paracuellos
2021-07-03 11:32 ` Andy Shevchenko
2021-07-03 12:05 ` Sergio Paracuellos
2021-07-03 12:51 ` Sergio Paracuellos
2021-07-03 19:36 ` Andy Shevchenko
2021-07-04 5:57 ` Sergio Paracuellos
2021-07-04 8:06 ` Sergio Paracuellos
2021-07-04 10:04 ` Andy Shevchenko
2021-07-04 11:25 ` Sergio Paracuellos
2021-07-04 11:35 ` Andy Shevchenko
2021-07-04 20:07 ` Sergio Paracuellos
2021-07-04 20:15 ` Sergio Paracuellos
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=CAMhs-H9gw63j98vVo3y0ymW4_6rFNL8u5cYNM2hzyrmkPB3h3w@mail.gmail.com \
--to=sergio.paracuellos@gmail.com \
--cc=andy.shevchenko@gmail.com \
--cc=bgolaszewski@baylibre.com \
--cc=git@johnthomson.fastmail.com.au \
--cc=hofrat@osadl.org \
--cc=linus.walleij@linaro.org \
--cc=linux-gpio@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=matthias.bgg@gmail.com \
--cc=neil@brown.name \
--cc=opensource@vdorst.com \
/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).