Linux-ACPI Archive on lore.kernel.org
 help / color / Atom feed
From: Lukasz Stelmach <l.stelmach@samsung.com>
To: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	Heikki Krogerus <heikki.krogerus@linux.intel.com>,
	Mika Westerberg <mika.westerberg@linux.intel.com>,
	Linus Walleij <linus.walleij@linaro.org>,
	Ard Biesheuvel <ard.biesheuvel@linaro.org>,
	linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org,
	platform-driver-x86@vger.kernel.org,
	Marek Szyprowski <m.szyprowski@samsung.com>,
	Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Subject: Re: [PATCH v8 3/6] software node: implement reference properties
Date: Mon, 09 Nov 2020 20:54:59 +0100
Message-ID: <dleftjr1p2nw4s.fsf%l.stelmach@samsung.com> (raw)
In-Reply-To: <20201109185305.GT1003057@dtor-ws> (Dmitry Torokhov's message of "Mon, 9 Nov 2020 10:53:05 -0800")


[-- Attachment #1: Type: text/plain, Size: 2802 bytes --]

It was <2020-11-09 pon 10:53>, when Dmitry Torokhov wrote:
> On Mon, Nov 09, 2020 at 07:18:37PM +0100, Lukasz Stelmach wrote:
>> It was <2020-11-09 pon 19:24>, when Andy Shevchenko wrote:
>> > On Mon, Nov 09, 2020 at 06:02:29PM +0100, Lukasz Stelmach wrote:
>> >> It was <2019-11-07 czw 20:22>, when Dmitry Torokhov wrote:
>> >> > It is possible to store references to software nodes in the same fashion as
>> >> > other static properties, so that users do not need to define separate
>> >> > structures:
>> >> >
>> >> > static const struct software_node gpio_bank_b_node = {
>> >> > 	.name = "B",
>> >> > };
>> >> >
>> >> > static const struct property_entry simone_key_enter_props[] = {
>> >> > 	PROPERTY_ENTRY_U32("linux,code", KEY_ENTER),
>> >> > 	PROPERTY_ENTRY_STRING("label", "enter"),
>> >> > 	PROPERTY_ENTRY_REF("gpios", &gpio_bank_b_node, 123, GPIO_ACTIVE_LOW),
>> >> > 	{ }
>> >> > };
>> >> >
>> >> > Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
>> >> > ---
>> >> 
>> >> I am writing a piece that needs to provide a list of gpios to a
>> >> diriver. The above example looks like what I need.
>> >
>> > Nope.
>> >
>> > It mustn't be used for GPIOs or PWMs or whatever that either should come via
>> > lookup tables or corresponding firmware interface.
>> >
>> 
>> May I ask why? I've read commit descriptions for drivers/base/swnode.c
>> and the discussion on lkml and I understand software nodes as a way to
>> provide (synthesize) a description for a device that is missing a
>> description in the firmware. Another use case seems to be to replace (in
>> the long run) platform data. That is what I am trying to use it for.
>> 
>> I want my device to be configured with either DT or software_nodes
>> created at run time with configfs. My device is going to use GPIOs
>> described in the DT and it is going to be configured via configfs at run
>> time. I could use platform_data to pass structures from configfs but
>> software nodes would let me save some code in the device driver and use
>> the same paths for both static (DT) and dynamic (configfs)
>> configuration.
>> 
>> Probably I have missed something and I will be greatful, if you tell me
>> where I can find more information about software nodes. There are few
>> users in the kernel and it isn't obvious for me how to use software
>> nodes properly.
>
> Yeah, I disagree with Andy here. The lookup tables are a crutch that we
> have until GPIO and PWM a taught to support software nodes (I need to
> resurrect my patch series for GPIO, if you have time to test that would
> be awesome).

It will be great to help. I am not sure if I have means to test PWMs,
but I can do GPIOs.

-- 
Łukasz Stelmach
Samsung R&D Institute Poland
Samsung Electronics

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 487 bytes --]

  parent reply index

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-08  4:22 [PATCH v8 0/6] software node: add support for " Dmitry Torokhov
2019-11-08  4:22 ` [PATCH v8 1/6] software node: rename is_array to is_inline Dmitry Torokhov
2019-11-08  9:49   ` Rafael J. Wysocki
2019-11-13  6:52   ` Bjørn Mork
2019-11-13  8:08     ` Dmitry Torokhov
     [not found]   ` <CGME20191212111237eucas1p1a278d2d5d2437e3219896367e82604cc@eucas1p1.samsung.com>
2019-12-12 11:12     ` Marek Szyprowski
2019-12-12 11:28       ` Andy Shevchenko
2019-12-12 16:41         ` Rafael J. Wysocki
2019-12-13  6:47           ` Marek Szyprowski
2019-12-13  8:37             ` Rafael J. Wysocki
2019-12-13  1:24       ` Dmitry Torokhov
2019-12-13  6:44         ` Marek Szyprowski
2019-11-08  4:22 ` [PATCH v8 2/6] software node: allow embedding of small arrays into property_entry Dmitry Torokhov
2019-11-08  4:22 ` [PATCH v8 3/6] software node: implement reference properties Dmitry Torokhov
     [not found]   ` <CGME20201109170241eucas1p14c2156334d8c6ef15d52664fa4776f41@eucas1p1.samsung.com>
2020-11-09 17:02     ` Lukasz Stelmach
2020-11-09 17:24       ` Andy Shevchenko
     [not found]         ` <CGME20201109181851eucas1p241de8938e399c0b603c764593b057c41@eucas1p2.samsung.com>
2020-11-09 18:18           ` Lukasz Stelmach
2020-11-09 18:53             ` Dmitry Torokhov
2020-11-09 19:05               ` Andy Shevchenko
2020-11-10 12:39                 ` Heikki Krogerus
2020-11-10 12:46                   ` Rafael J. Wysocki
     [not found]               ` <CGME20201109195504eucas1p19d493c947d8752e39c26202cf0978fc0@eucas1p1.samsung.com>
2020-11-09 19:54                 ` Lukasz Stelmach [this message]
2020-11-09 19:02             ` Andy Shevchenko
     [not found]               ` <CGME20201109194725eucas1p2cc9357486879a14b2ad2f6ef968ff4b2@eucas1p2.samsung.com>
2020-11-09 19:47                 ` Lukasz Stelmach
2020-11-09 21:20                   ` Andy Shevchenko
2019-11-08  4:22 ` [PATCH v8 4/6] platform/x86: intel_cht_int33fe: use inline " Dmitry Torokhov
2019-11-08  4:22 ` [PATCH v8 5/6] software node: remove separate handling of references Dmitry Torokhov
2019-11-08  4:22 ` [PATCH v8 6/6] software node: add basic tests for property entries Dmitry Torokhov

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=dleftjr1p2nw4s.fsf%l.stelmach@samsung.com \
    --to=l.stelmach@samsung.com \
    --cc=andriy.shevchenko@linux.intel.com \
    --cc=ard.biesheuvel@linaro.org \
    --cc=b.zolnierkie@samsung.com \
    --cc=dmitry.torokhov@gmail.com \
    --cc=heikki.krogerus@linux.intel.com \
    --cc=linus.walleij@linaro.org \
    --cc=linux-acpi@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=m.szyprowski@samsung.com \
    --cc=mika.westerberg@linux.intel.com \
    --cc=platform-driver-x86@vger.kernel.org \
    --cc=rafael@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

Linux-ACPI Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-acpi/0 linux-acpi/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-acpi linux-acpi/ https://lore.kernel.org/linux-acpi \
		linux-acpi@vger.kernel.org
	public-inbox-index linux-acpi

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-acpi


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git