public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: "Lawrence,Wang" <lawrence.wang@nokia-sbell.com>
Cc: jarkko.nikula@linux.intel.com, mika.westerberg@linux.intel.com,
	linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org,
	Wang@wrlinb193.emea.nsn-net.net
Subject: Re: [PATCH] i2c: designware: Get HCNT/LCNT values from dts
Date: Mon, 15 Nov 2021 12:19:26 +0200	[thread overview]
Message-ID: <YZI0LuDK63+Wb7wi@smile.fi.intel.com> (raw)
In-Reply-To: <20211115093556.7154-1-lawrence.wang@nokia-sbell.com>

On Mon, Nov 15, 2021 at 10:35:55AM +0100, Lawrence,Wang wrote:
> From: "Wang, Lawrence" <lawrence.wang@nokia-sbell.com>
> 
> Current code support config the HCNT/LCNT only via ACPI method. for those
> platform that not support ACPI, will get the HCNT/LCNT value based on input
> clock. But it is not always accuracy. for example in some platform will get
> lower speed(320khz) in fast mode, and get faster speed(105khz/even more) in
> standard mode.
> 
> This patch makes it possible for the non-ACPI platform to pass more optimal
> HCNT/LCNT values to the core driver via dts if they are known beforehand.
> If these are not set we use the calculated values.

Besides the fact it misses DT schema update, why this is needed at all?
What's wrong with the existing DT timings?

So far seems NAK to me.

...

> +	ret = device_property_read_u16_array(dev->dev, "dw-i2c-scl-timing",
> +					(u16 *)&i2c_scl_timing, sizeof(i2c_scl_timing)/sizeof(u16));
> +	if (ret)
> +		return;

No, you have to have one property per each value AFAIU DT schema requirements,
Ask Rob Herring about it.

-- 
With Best Regards,
Andy Shevchenko



  reply	other threads:[~2021-11-15 10:19 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-11-15  9:35 [PATCH] i2c: designware: Get HCNT/LCNT values from dts Lawrence,Wang
2021-11-15 10:19 ` Andy Shevchenko [this message]
2021-11-15 10:28   ` Andy Shevchenko
2021-11-15 10:41     ` Wang, Lawrence (NSB - CN/Hangzhou)
2021-11-15 11:01       ` Andy Shevchenko
2021-11-16  1:43         ` Wang, Lawrence (NSB - CN/Hangzhou)
2021-11-29 19:28 ` Wolfram Sang

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=YZI0LuDK63+Wb7wi@smile.fi.intel.com \
    --to=andriy.shevchenko@linux.intel.com \
    --cc=Wang@wrlinb193.emea.nsn-net.net \
    --cc=jarkko.nikula@linux.intel.com \
    --cc=lawrence.wang@nokia-sbell.com \
    --cc=linux-i2c@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mika.westerberg@linux.intel.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