From: Guenter Roeck <linux@roeck-us.net>
To: Marius Zachmann <mail@mariuszachmann.de>
Cc: Jean Delvare <jdelvare@suse.com>,
Jonathan Corbet <corbet@lwn.net>,
linux-hwmon@vger.kernel.org, linux-doc@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] hwmon: corsair-cpro: Change to hid driver
Date: Wed, 15 Jul 2020 07:44:41 -0700 [thread overview]
Message-ID: <20200715144441.GC201840@roeck-us.net> (raw)
In-Reply-To: <1747396.iuIVfOqGsT@marius>
On Wed, Jul 15, 2020 at 08:59:52AM +0200, Marius Zachmann wrote:
> On 15.07.20 at 04:36:22 CEST, Guenter Roeck wrote
> > On Tue, Jul 14, 2020 at 12:52:30PM +0200, Marius Zachmann wrote:
> > > I found a project which uses hidraw to communicate with the device.
> > > Because I do not want to break any existing userspace code, I
> > > changed this to a hid driver, so hidraw can still be used.
> > > Do I need to include the hid maintainers for the undo in hid-quirks?
> > >
> > That changelog needs some improvements. It should state what change
> > was made, and why, but not include any questions or personal statements
> > such as "I found ...".
> >
> > You never really explained why you had changed the driver from hid to
> > usb. Maybe you can explain that decision now ?
> >
> > Thanks,
> > Guenter
> >
>
> This device does not use numbered hid input reports. As far as I know
> it is not possible to determine from which command a response was
> requested. This being a usb driver would not allow any other driver
> to send data to the device.
> In the first (hid) version I did not use hid reports and got
> the usb_device directly from the hid_device which is not intended.
> In this version, requests are made via hid_hw_output_report, waited
> for and received via raw_event.
> If one uses hidraw and this driver at the same time, it still could
> be possible to get switched responses but there is nothing I can
> do about it, as far as I know. This is only about giving the
> possibility to unload the driver and using a userspace driver
> if one chooses.
>
What a mess. Can you add some of this as comment to the top of the driver
to explain the reasoning ?
Thanks,
Guenter
next prev parent reply other threads:[~2020-07-15 14:44 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-14 10:52 [PATCH] hwmon: corsair-cpro: Change to hid driver Marius Zachmann
2020-07-15 2:36 ` Guenter Roeck
2020-07-15 6:59 ` Marius Zachmann
2020-07-15 14:44 ` Guenter Roeck [this message]
2020-07-15 14:39 ` Guenter Roeck
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=20200715144441.GC201840@roeck-us.net \
--to=linux@roeck-us.net \
--cc=corbet@lwn.net \
--cc=jdelvare@suse.com \
--cc=linux-doc@vger.kernel.org \
--cc=linux-hwmon@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mail@mariuszachmann.de \
/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).