From: Stephen Boyd <sboyd@codeaurora.org>
To: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Cc: Russell King - ARM Linux <linux@armlinux.org.uk>,
Rob Herring <robh@kernel.org>,
Linux-ALSA <alsa-devel@alsa-project.org>,
Linux-DT <devicetree@vger.kernel.org>,
Michael Turquette <mturquette@baylibre.com>,
Linux-Kernel <linux-kernel@vger.kernel.org>,
Mark Brown <broonie@kernel.org>,
linux-clk@vger.kernel.org,
Linux-ARM <linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH 2/3] ASoC: simple-card: use devm_get_clk_from_child()
Date: Thu, 8 Dec 2016 16:28:37 -0800 [thread overview]
Message-ID: <20161209002837.GE5423@codeaurora.org> (raw)
In-Reply-To: <877f7aymxu.wl%kuninori.morimoto.gx@renesas.com>
On 12/09, Kuninori Morimoto wrote:
>
> Hi Stephen
>
> > > @@ -111,14 +112,13 @@ int asoc_simple_card_parse_clk(struct device_node *node,
> > > * or "system-clock-frequency = <xxx>"
> > > * or device's module clock.
> > > */
> > > - clk = of_clk_get(node, 0);
> > > + clk = devm_get_clk_from_child(dev, node, NULL);
> > > if (!IS_ERR(clk)) {
> > > simple_dai->sysclk = clk_get_rate(clk);
> > > - simple_dai->clk = clk;
> > > } else if (!of_property_read_u32(node, "system-clock-frequency", &val)) {
> > > simple_dai->sysclk = val;
> > > } else {
> > > - clk = of_clk_get(dai_of_node, 0);
> > > + clk = devm_get_clk_from_child(dev, dai_of_node, NULL);
> >
> >
> > I was confused for a minute about how the second of_clk_get()
> > call with the dai_link node could work. Is that documented
> > anywhere or used by anyone? It seems like it's at least another
> > child node of the sound node (which is dev here) so it seems ok.
>
> Documentation/devicetree/bindings/sound/simple-card.txt
> explains 1st of_clk_get will be used as "if needed",
> 2nd of_clk_get will be used as "not needed pattern".
> 1st pattern will use specific clock, 2nd pattern will use
> "cpu" or "codec" clock.
> 2nd one was added by someone (I forgot), and many driver is
> based on this feature.
>
Can you point to some dts file in the kernel that falls into the
devm_get_clk_from_child(dev, dai_of_node, NULL) part?
--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project
next prev parent reply other threads:[~2016-12-09 0:28 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-12-05 5:22 [PATCH 0/3] clkdev: add devm_get_clk_from_child() Kuninori Morimoto
2016-12-05 5:23 ` [PATCH 1/3] " Kuninori Morimoto
2016-12-09 20:31 ` Russell King - ARM Linux
2016-12-05 5:23 ` [PATCH 2/3] ASoC: simple-card: use devm_get_clk_from_child() Kuninori Morimoto
2016-12-08 22:09 ` Stephen Boyd
2016-12-09 0:20 ` Kuninori Morimoto
2016-12-09 0:28 ` Stephen Boyd [this message]
2016-12-09 0:33 ` Kuninori Morimoto
2017-01-24 18:39 ` Applied "ASoC: simple-card: use devm_get_clk_from_child()" to the asoc tree Mark Brown
2016-12-05 5:23 ` [PATCH 3/3] ASoC: simple-card-utils: enable clocks/clock-names/clock-ranges Kuninori Morimoto
2016-12-08 22:09 ` Stephen Boyd
2016-12-09 0:21 ` Kuninori Morimoto
2016-12-09 0:22 ` Kuninori Morimoto
2016-12-09 0:26 ` Stephen Boyd
2016-12-09 0:55 ` Kuninori Morimoto
2016-12-08 22:08 ` [PATCH 0/3] clkdev: add devm_get_clk_from_child() Stephen Boyd
2016-12-09 0:25 ` Kuninori Morimoto
2016-12-15 12:21 ` Mark Brown
2016-12-16 0:02 ` Kuninori Morimoto
2017-03-29 1:16 ` Question about of_clk_put ? Kuninori Morimoto
2017-03-30 1:46 ` [alsa-devel] " Kuninori Morimoto
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=20161209002837.GE5423@codeaurora.org \
--to=sboyd@codeaurora.org \
--cc=alsa-devel@alsa-project.org \
--cc=broonie@kernel.org \
--cc=devicetree@vger.kernel.org \
--cc=kuninori.morimoto.gx@renesas.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-clk@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@armlinux.org.uk \
--cc=mturquette@baylibre.com \
--cc=robh@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).