From: Andy Shevchenko <andy.shevchenko@gmail.com>
To: LI Qingwu <qing-wu.li@leica-geosystems.com.cn>
Cc: Jonathan Cameron <jic23@kernel.org>,
Lars-Peter Clausen <lars@metafoo.de>,
Rob Herring <robh+dt@kernel.org>,
Tomas Melin <tomas.melin@vaisala.com>,
devicetree <devicetree@vger.kernel.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
linux-iio <linux-iio@vger.kernel.org>,
Rob Herring <robh@kernel.org>
Subject: Re: [PATCH V3 3/5] iio: accel: sca3300: modified to support multi chips
Date: Thu, 5 May 2022 20:01:22 +0200 [thread overview]
Message-ID: <CAHp75VcD-UpG=ppuE2Du2SsQK66MYdrwhXvjHksN5=gqcppYqA@mail.gmail.com> (raw)
In-Reply-To: <AM9PR06MB7844C01CA580F046FA570B43D7C29@AM9PR06MB7844.eurprd06.prod.outlook.com>
On Thu, May 5, 2022 at 4:12 PM LI Qingwu
<qing-wu.li@leica-geosystems.com.cn> wrote:
> > -----Original Message-----
> > From: Andy Shevchenko <andy.shevchenko@gmail.com>
> > Sent: Wednesday, May 4, 2022 10:39 PM
> > On Wed, May 4, 2022 at 4:35 PM LI Qingwu
> > <qing-wu.li@leica-geosystems.com.cn> wrote:
> > > > From: Andy Shevchenko <andy.shevchenko@gmail.com>
> > > > Sent: Wednesday, May 4, 2022 10:20 PM On Wed, May 4, 2022 at 3:36 PM
> > > > LI Qingwu <Qing-wu.Li@leica-geosystems.com.cn> wrote:
...
> > > > > +struct sca3300_chip_info {
> > > > > + const struct iio_chan_spec *channels;
> > > > > + const int (*accel_scale_table)[2];
> > > > > + const int *accel_scale_modes_map;
> > > > > + const unsigned long *scan_masks;
> > > > > + const int *avail_modes_table;
> > > > > + const int *freq_modes_map;
> > > > > + const int *freq_table;
> > > > > + const u8 num_accel_scales;
> > > > > + const u8 num_avail_modes;
> > > > > + const u8 num_channels;
> > > > > + const u8 num_freqs;
> > > > > + const u8 chip_id;
> > > >
> > > > Why do you have const qualifier on all members? The last one is
> > > > understandable, but the rest, esp. pointers should be justified.
> > > Because I thought it was static and has fix value for each chip, unacceptable
> > for you?
> >
> > But why const qualifier? What is the point of it for example for u8 members if
> > the entire object is qualified as const below in the same patch?
> >
> > On top of that, please explain what in your opinion the "const ...
> > *foo" gives us, and what we will lose if we remove the "const" part out of them.
>
> Ah, you are right, those const are unnecessary for nonpointer members.
> for the pointers, the contexts that the pointer points to are still writable.
> what about if I remove all the const from nonpointer and keep it for the pointers?
> Like:
> const struct iio_chan_spec *channels;
> const int (*accel_scale_table)[2];
> const int (*incli_scale_table)[2];
> const int *accel_scale_modes_map;
> const int *incli_scale_modes_map;
> const unsigned long *scan_masks;
> const int *avail_modes_table;
> const int *freq_modes_map;
> const int *freq_table;
> const char *name;
> u8 num_accel_scales;
> u8 num_incli_scales;
> u8 num_avail_modes;
> u8 num_channels;
> u8 num_freqs;
> u8 chip_id;
> bool angle;
It's better, but you still need to justify the rest with explanation
in the commit message.
And I leave this to maintainers to say if the const:s are needed or not.
> > > > > + const char *name;
> > > > > +};
--
With Best Regards,
Andy Shevchenko
next prev parent reply other threads:[~2022-05-05 18:02 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-05-04 13:36 [PATCH V3 0/5] iio: accel: sca3300: add compitible for scl3300 LI Qingwu
2022-05-04 13:36 ` [PATCH V3 1/5] dt-bindings: iio: accel: sca3300: Document murata,scl3300 LI Qingwu
2022-05-04 13:36 ` [PATCH V3 2/5] iio: accel: sca3300: add define for temp channel for reuse LI Qingwu
2022-05-04 13:36 ` [PATCH V3 3/5] iio: accel: sca3300: modified to support multi chips LI Qingwu
2022-05-04 14:20 ` Andy Shevchenko
2022-05-04 14:35 ` LI Qingwu
2022-05-04 14:38 ` Andy Shevchenko
2022-05-05 14:12 ` LI Qingwu
2022-05-05 18:01 ` Andy Shevchenko [this message]
2022-05-07 14:42 ` Jonathan Cameron
2022-05-06 20:12 ` Melin Tomas
2022-05-07 3:48 ` LI Qingwu
2022-05-06 20:12 ` Melin Tomas
2022-05-07 14:54 ` Jonathan Cameron
2022-05-04 13:36 ` [PATCH V3 4/5] iio: accel: sca3300: Add support for SCL3300 LI Qingwu
2022-05-04 13:36 ` [PATCH V3 5/5] iio: accel: sca3300: Add inclination channels LI Qingwu
2022-05-04 17:23 ` kernel test robot
2022-05-07 14:46 ` 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='CAHp75VcD-UpG=ppuE2Du2SsQK66MYdrwhXvjHksN5=gqcppYqA@mail.gmail.com' \
--to=andy.shevchenko@gmail.com \
--cc=devicetree@vger.kernel.org \
--cc=jic23@kernel.org \
--cc=lars@metafoo.de \
--cc=linux-iio@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=qing-wu.li@leica-geosystems.com.cn \
--cc=robh+dt@kernel.org \
--cc=robh@kernel.org \
--cc=tomas.melin@vaisala.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;
as well as URLs for NNTP newsgroup(s).