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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Andy Shevchenko' <andriy.shevchenko@linux.intel.com>,
        Takashi Iwai <tiwai@suse.de>
CC:     "alsa-devel@alsa-project.org" <alsa-devel@alsa-project.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "Jaroslav Kysela" <perex@perex.cz>, Takashi Iwai <tiwai@suse.com>,
        Dan Williams <dan.j.williams@intel.com>
Subject: RE: [PATCH v1 1/1] ALSA: korg1212: Re-use sockptr_t and respective
 APIs
Thread-Topic: [PATCH v1 1/1] ALSA: korg1212: Re-use sockptr_t and respective
 APIs
Thread-Index: AQHZu8ALiLW3NE9rpEyBJunRSGnWfK/EPjVA
Date:   Fri, 21 Jul 2023 13:58:52 +0000
Message-ID: <b8e6f7ae1e684f85902cb3a787436bd9@AcuMS.aculab.com>
References: <20230721100146.67293-1-andriy.shevchenko@linux.intel.com>
 <878rb9h901.wl-tiwai@suse.de> <ZLphAJG4Tz8zLUSN@smile.fi.intel.com>
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From: Andy Shevchenko
> Sent: 21 July 2023 11:42
> 
> On Fri, Jul 21, 2023 at 12:08:46PM +0200, Takashi Iwai wrote:
> > On Fri, 21 Jul 2023 12:01:46 +0200,
> > Andy Shevchenko wrote:
> > >
> > > The sockptr_t (despite the naming) is a generic type to hold kernel
> > > or user pointer and there are respective APIs to copy data to or
> > > from it. Replace open coded variants in the driver by them.
> >
> > While I see the benefit, I feel this is very confusing.  If we use the
> > API for a generic use, it should be renamed at first.
> >
> > Also, the current function actually follows the call pattern, and we
> > know in the caller side whether it's called for a kernel pointer or a
> > user pointer.  So, if any, the PCM core callbacks should be revised to
> > use a generic pointer instead of fiddling in each driver side.
> 
> Any suggestion for the name?
> And I believe for the bigger series the new callback should be added first.

It would also be better to replace the current sockptr_t with
a structure that contains separate user and kernel addresses
(instead of a union of the pointer types and a flag).

The size of the structure wouldn't change and the code might
even come out better.

There is also scope for adding a length and passing the structure
by reference instead of by value.

	David

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