All of lore.kernel.org
 help / color / mirror / Atom feed
From: Wolfram Sang <wsa@kernel.org>
To: Alexander Stein <alexander.stein@ew.tq-group.com>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>,
	NXP Linux Team <linux-imx@nxp.com>,
	"A. Sverdlin" <alexander.sverdlin@siemens.com>,
	Dong Aisheng <aisheng.dong@nxp.com>,
	Shawn Guo <shawnguo@kernel.org>,
	Sascha Hauer <s.hauer@pengutronix.de>,
	Pengutronix Kernel Team <kernel@pengutronix.de>,
	Fabio Estevam <festevam@gmail.com>,
	linux-i2c@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3] i2c: lpi2c: cache peripheral clock rate
Date: Sun, 30 Apr 2023 09:05:55 +0200	[thread overview]
Message-ID: <ZE4TU0rCw9MSwrmB@sai> (raw)
In-Reply-To: <4797405.GXAFRqVoOG@steina-w>

[-- Attachment #1: Type: text/plain, Size: 540 bytes --]


> > IIRC this is a general problem^w limitation of the clock framework,
> > clock providers cannot use clocks themselves in certain callback, e.g.
> > set_rate.
> 
> Well, that's essentially impossible when this clock provider is attached via 
> i2c. i2c transfers potentially need to change or prepare clocks.

So, as I get it, this is not a specific lpi2c problem but affecting any
I2C controller driver which uses get_rate() to setup a transfer to a
remote I2C clock provider? And this lockdep warning is a false-positive?


[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

WARNING: multiple messages have this Message-ID (diff)
From: Wolfram Sang <wsa@kernel.org>
To: Alexander Stein <alexander.stein@ew.tq-group.com>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>,
	NXP Linux Team <linux-imx@nxp.com>,
	"A. Sverdlin" <alexander.sverdlin@siemens.com>,
	Dong Aisheng <aisheng.dong@nxp.com>,
	Shawn Guo <shawnguo@kernel.org>,
	Sascha Hauer <s.hauer@pengutronix.de>,
	Pengutronix Kernel Team <kernel@pengutronix.de>,
	Fabio Estevam <festevam@gmail.com>,
	linux-i2c@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3] i2c: lpi2c: cache peripheral clock rate
Date: Sun, 30 Apr 2023 09:05:55 +0200	[thread overview]
Message-ID: <ZE4TU0rCw9MSwrmB@sai> (raw)
In-Reply-To: <4797405.GXAFRqVoOG@steina-w>


[-- Attachment #1.1: Type: text/plain, Size: 540 bytes --]


> > IIRC this is a general problem^w limitation of the clock framework,
> > clock providers cannot use clocks themselves in certain callback, e.g.
> > set_rate.
> 
> Well, that's essentially impossible when this clock provider is attached via 
> i2c. i2c transfers potentially need to change or prepare clocks.

So, as I get it, this is not a specific lpi2c problem but affecting any
I2C controller driver which uses get_rate() to setup a transfer to a
remote I2C clock provider? And this lockdep warning is a false-positive?


[-- Attachment #1.2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

[-- Attachment #2: Type: text/plain, Size: 176 bytes --]

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2023-04-30  7:06 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-10 13:08 [PATCH v3] i2c: lpi2c: cache peripheral clock rate A. Sverdlin
2023-03-10 13:08 ` A. Sverdlin
2023-04-21 13:48 ` Alexander Stein
2023-04-21 13:48   ` Alexander Stein
2023-04-21 13:59   ` Marc Kleine-Budde
2023-04-21 13:59     ` Marc Kleine-Budde
2023-04-24  7:03     ` Alexander Stein
2023-04-24  7:03       ` Alexander Stein
2023-04-30  7:05       ` Wolfram Sang [this message]
2023-04-30  7:05         ` Wolfram Sang
2023-05-02  6:50         ` Alexander Stein
2023-05-02  6:50           ` Alexander Stein
2023-05-02  7:03           ` Marc Kleine-Budde
2023-05-02  7:03             ` Marc Kleine-Budde
2023-04-21 14:10   ` Sverdlin, Alexander
2023-04-21 14:10     ` Sverdlin, Alexander
2023-05-15  9:11   ` Alexander Stein
2023-05-15  9:11     ` Alexander Stein
2023-05-15 12:04     ` Sverdlin, Alexander
2023-05-15 12:04       ` Sverdlin, Alexander
2023-05-15 12:32       ` Alexander Stein
2023-05-15 12:32         ` Alexander Stein
2023-05-15 12:37         ` Sverdlin, Alexander
2023-05-15 12:37           ` Sverdlin, Alexander
2023-05-15 13:11   ` Sverdlin, Alexander
2023-05-15 13:11     ` Sverdlin, Alexander
2023-04-24  8:08 ` Alexander Stein
2023-04-24  8:08   ` Alexander Stein

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=ZE4TU0rCw9MSwrmB@sai \
    --to=wsa@kernel.org \
    --cc=aisheng.dong@nxp.com \
    --cc=alexander.stein@ew.tq-group.com \
    --cc=alexander.sverdlin@siemens.com \
    --cc=festevam@gmail.com \
    --cc=kernel@pengutronix.de \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-i2c@vger.kernel.org \
    --cc=linux-imx@nxp.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mkl@pengutronix.de \
    --cc=s.hauer@pengutronix.de \
    --cc=shawnguo@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.