All of lore.kernel.org
 help / color / mirror / Atom feed
From: Wolfram Sang <wsa@the-dreams.de>
To: Rob Herring <robh@kernel.org>
Cc: Guenter Roeck <linux@roeck-us.net>,
	Wojciech Slenska <wojciech.slenska@gmail.com>,
	Jean Delvare <jdelvare@suse.com>,
	Mark Rutland <mark.rutland@arm.com>,
	Linux HWMON List <linux-hwmon@vger.kernel.org>,
	devicetree@vger.kernel.org, Linux I2C <linux-i2c@vger.kernel.org>
Subject: Re: [PATCH v2] hwmon: (sht3x) add devicetree support
Date: Thu, 18 Oct 2018 20:07:21 +0200	[thread overview]
Message-ID: <20181018180721.GA941@kunai> (raw)
In-Reply-To: <CAL_JsqK62Yi9+w=06LrsiDCgLp9W0WmfYTL9QCv98Qfij7Zbbw@mail.gmail.com>

[-- Attachment #1: Type: text/plain, Size: 962 bytes --]

Hi,

> And here's another device with programmable clock stretching[1]. Lots
> of discussions in searching about masters not supporting clock
> stretching more than I found of slaves which are configurable. At
> least in that case, we should be able to derive it from master
> compatible strings. But for the cases where both ends can support
> stretching or not, seems like we need an i2c property.

I haven't read all this, but regarding clock stretching, this is the
current state:

* clock streching is defined in the I2C specs and thus masters are
  assumed to handle it properly
* if they can't, this is a quirk and we have a flag for it:
  I2C_AQ_NO_CLK_STRETCH
* client drivers can check for quirks and act accordingly:
  i2c_check_quirks(struct i2c_adapter *adap, u64 quirks)

Note: there is currently no user of this feature because mainlining the
client got stuck for some reason. So, I'd be happy if all this is useful
to you.

Regards,

   Wolfram


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

      parent reply	other threads:[~2018-10-18 18:07 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-10-05  5:38 [PATCH v2] hwmon: (sht3x) add devicetree support Wojciech Slenska
2018-10-12 20:28 ` Rob Herring
2018-10-15  5:55   ` Wojciech Sleńska
2018-10-15 19:54     ` Guenter Roeck
2018-10-16 18:02       ` Rob Herring
2018-10-16 23:38         ` Guenter Roeck
2018-10-18 13:47           ` Rob Herring
2018-10-18 14:41             ` Guenter Roeck
2018-10-18 16:06               ` Rob Herring
2018-10-18 16:58                 ` Guenter Roeck
2018-10-18 18:07                 ` Wolfram Sang [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=20181018180721.GA941@kunai \
    --to=wsa@the-dreams.de \
    --cc=devicetree@vger.kernel.org \
    --cc=jdelvare@suse.com \
    --cc=linux-hwmon@vger.kernel.org \
    --cc=linux-i2c@vger.kernel.org \
    --cc=linux@roeck-us.net \
    --cc=mark.rutland@arm.com \
    --cc=robh@kernel.org \
    --cc=wojciech.slenska@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 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.