From: Jerome Brunet <jbrunet@baylibre.com>
To: Vyacheslav Yurkov <uvv.mail@gmail.com>,
Vyacheslav Yurkov via B4 Relay
<devnull+V.Yurkov.EXT.bruker.com@kernel.org>,
Michael Turquette <mturquette@baylibre.com>,
Stephen Boyd <sboyd@kernel.org>, Rob Herring <robh@kernel.org>,
Krzysztof Kozlowski <krzk+dt@kernel.org>,
Conor Dooley <conor+dt@kernel.org>,
Brian Masney <bmasney@redhat.com>,
Brian Masney <bmasney+clk@redhat.com>,
Jerome Brunet <jbrunet+clk@baylibre.com>,
Jyri Sarha <jsarha@ti.com>
Cc: linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org,
devicetree@vger.kernel.org,
Vyacheslav Yurkov <V.Yurkov.EXT@bruker.com>
Subject: Re: [PATCH v5 2/2] clk: Add gpio-locked fixed clock driver
Date: Fri, 25 Sep 2026 16:22:16 +0200 [thread overview]
Message-ID: <1jzex576nb.fsf@starbuckisacylon.baylibre.com> (raw)
In-Reply-To: <a5e76452-1fa1-4675-9a16-8683702ff4d0@gmail.com>
On ven. 25 sept. 2026 at 15:15, Vyacheslav Yurkov <uvv.mail@gmail.com> wrote:
> On 25.09.2026 13:57, Jerome Brunet wrote:
>> On jeu. 17 sept. 2026 at 19:05, Vyacheslav Yurkov <uvv.mail@gmail.com> wrote:
>>
>>> On 16.09.2026 15:57, Jerome Brunet wrote:
>>>
>>>>>>> +/* We can't enable the clock, but the Common Clock Framework calls only
>>>>>>> + * enable() not is_enabled()
>>>>>>> + */
>>>>>>> +static int gpio_locked_clk_enable(struct clk_hw *hw)
>>>>>>> +{
>>>>>>> + return gpio_locked_clk_is_enabled(hw);
>>>>>>> +}
>>>>
>>>> You need to explain your problem a bit more because this is not OK. Your
>>>> clock should really just provide .is_enabled() AFAICT
>>>
>>> When a peripheral driver uses devm_clk_get_enabled(), this is resolved
>>> to clk_prepare() and clk_enable(). Neither of them check for
>>> .is_enabled(). Is that a flaw in the CCF or expected behavior?
>>>
>>
>> .enable() does return an error on failure. It is up to the provider to
>> return one or not. In your case, it will be probably be necessary to on
>> the gpio a little.
it will probably be necessary to poll on the gpio a little. (sorry)
>
> I'm not sure I understand what you meant.
>> Note that if the GPIO can sleep, interacting with the gpio must happen
>> in prepare (think i2c gpio devices)
>
> In other words, I should only provide prepare/unprepare instead? Do you
> think is_enabled can also be replaced by is_prepared in this case?
It depends on the GPIO API used. have a look at clk-gpio.c
>
> Slava
--
Jerome
prev parent reply other threads:[~2026-09-25 14:22 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-15 9:27 [PATCH v5 0/2] A proposal to add a " Vyacheslav Yurkov via B4 Relay
2026-09-15 9:27 ` [PATCH v5 1/2] dt-bindings: clock: gpio-gate-clock: Add a new compatible string Vyacheslav Yurkov via B4 Relay
2026-09-15 16:35 ` Conor Dooley
2026-09-15 9:27 ` [PATCH v5 2/2] clk: Add gpio-locked fixed clock driver Vyacheslav Yurkov via B4 Relay
2026-09-15 10:09 ` Jerome Brunet
2026-09-15 13:58 ` Vyacheslav Yurkov
2026-09-16 13:57 ` Jerome Brunet
2026-09-17 17:05 ` Vyacheslav Yurkov
2026-09-25 11:57 ` Jerome Brunet
2026-09-25 13:15 ` Vyacheslav Yurkov
2026-09-25 14:22 ` Jerome Brunet [this message]
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=1jzex576nb.fsf@starbuckisacylon.baylibre.com \
--to=jbrunet@baylibre.com \
--cc=V.Yurkov.EXT@bruker.com \
--cc=bmasney+clk@redhat.com \
--cc=bmasney@redhat.com \
--cc=conor+dt@kernel.org \
--cc=devicetree@vger.kernel.org \
--cc=devnull+V.Yurkov.EXT.bruker.com@kernel.org \
--cc=jbrunet+clk@baylibre.com \
--cc=jsarha@ti.com \
--cc=krzk+dt@kernel.org \
--cc=linux-clk@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mturquette@baylibre.com \
--cc=robh@kernel.org \
--cc=sboyd@kernel.org \
--cc=uvv.mail@gmail.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
all inboxes | Powered by JetHome®