All of lore.kernel.org
 help / color / mirror / Atom feed
From: Linus Walleij <linus.walleij@linaro.org>
To: Chris Lesiak <chris.lesiak@licor.com>
Cc: Jean Delvare <jdelvare@suse.com>,
	Guenter Roeck <linux@roeck-us.net>,
	"linux-hwmon@vger.kernel.org" <linux-hwmon@vger.kernel.org>,
	Peter Rosin <peda@axentia.se>, Jonathan Cameron <jic23@cam.ac.uk>,
	"linux-iio@vger.kernel.org" <linux-iio@vger.kernel.org>
Subject: Re: [PATCH v2] hwmon: (ntc_thermistor): try reading processed
Date: Sun, 27 Dec 2020 22:47:47 +0100	[thread overview]
Message-ID: <CACRpkdYVruMggRHtOLWZ01N5yYx8GqAK3OtKC13Z=669eznurA@mail.gmail.com> (raw)
In-Reply-To: <SN6PR08MB55654976327EF62990D4DD919ADA0@SN6PR08MB5565.namprd08.prod.outlook.com>

On Sun, Dec 27, 2020 at 7:54 PM Chris Lesiak <chris.lesiak@licor.com> wrote:
> Linus Walleij <linus.walleij@linaro.org> wrote:
> > But do you agree with the general stance that we should
> > give precedence to using iio_read_channel_processed()
> > and multiply the result with 1000? It should work with
> > any driver I think.
>
> In order to preserve resolution of the microVolt value for existing code,

Aha you mean that iio_read_channel_processed() loses
precision when converting raw to scaled?

> I'd prefer a solution similar to the existing implementation of
> iio_read_channel_processed.

That seems like the wrong way to work around a problem in
the core.

If iio_read_channel_processed() loses precision we should
fix iio_read_channel_processed() and not try to work around
the problem in the consumers.

It's fine to fix all the consumers in the kernel.

What about changing the signature of:

int iio_read_channel_processed(struct iio_channel *chan, int *val)

to:

int iio_read_channel_processed(struct iio_channel *chan, int *val,
unsigned int scale)

And just augment all calls to pass 1 except the ntc driver
which then passes 1000 in the last argument?

If Jonathan agrees I can fix a patch to alter all the ~50
call sites like this and include the change to this NTC
driver.

Yours,
Linus Walleij

  reply	other threads:[~2020-12-27 21:48 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-24  1:16 Linus Walleij
2020-12-24  1:39 ` Chris Lesiak
2020-12-24  3:15   ` Chris Lesiak
2020-12-25 23:01     ` Linus Walleij
2020-12-25 22:55   ` Linus Walleij
2020-12-26  1:45     ` Chris Lesiak
2020-12-27 13:46       ` Linus Walleij
2020-12-27 18:54         ` Chris Lesiak
2020-12-27 21:47           ` Linus Walleij [this message]
2020-12-27 22:08             ` Chris Lesiak
2020-12-29 14:25               ` Jonathan Cameron
2020-12-29 16:33                 ` Guenter Roeck
2020-12-29 16:53                   ` Jonathan Cameron

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='CACRpkdYVruMggRHtOLWZ01N5yYx8GqAK3OtKC13Z=669eznurA@mail.gmail.com' \
    --to=linus.walleij@linaro.org \
    --cc=chris.lesiak@licor.com \
    --cc=jdelvare@suse.com \
    --cc=jic23@cam.ac.uk \
    --cc=linux-hwmon@vger.kernel.org \
    --cc=linux-iio@vger.kernel.org \
    --cc=linux@roeck-us.net \
    --cc=peda@axentia.se \
    --subject='Re: [PATCH v2] hwmon: (ntc_thermistor): try reading processed' \
    /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

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.