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Date:   Tue, 25 Jul 2023 08:52:23 +0200
Message-ID: <87fs5cv5y0.wl-tiwai@suse.de>
From:   Takashi Iwai <tiwai@suse.de>
To:     Greg KH <gregkh@linuxfoundation.org>
Cc:     Wesley Cheng <quic_wcheng@quicinc.com>, agross@kernel.org,
        andersson@kernel.org, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org,
        catalin.marinas@arm.com, will@kernel.org, mathias.nyman@intel.com,
        lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz,
        tiwai@suse.com, srinivas.kandagatla@linaro.org,
        bgoswami@quicinc.com, Thinh.Nguyen@synopsys.com,
        linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-usb@vger.kernel.org, alsa-devel@alsa-project.org,
        quic_jackp@quicinc.com, pierre-louis.bossart@linux.intel.com,
        oneukum@suse.com, albertccwang@google.com, o-takashi@sakamocchi.jp
Subject: Re: [PATCH v4 12/32] sound: usb: Export USB SND APIs for modules
In-Reply-To: <2023072542-playtime-charger-dcfc@gregkh>
References: <20230725023416.11205-1-quic_wcheng@quicinc.com>
        <20230725023416.11205-13-quic_wcheng@quicinc.com>
        <2023072542-playtime-charger-dcfc@gregkh>
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On Tue, 25 Jul 2023 07:33:57 +0200,
Greg KH wrote:
> 
> On Mon, Jul 24, 2023 at 07:33:56PM -0700, Wesley Cheng wrote:
> > --- a/sound/usb/pcm.c
> > +++ b/sound/usb/pcm.c
> > @@ -87,7 +87,7 @@ static snd_pcm_uframes_t snd_usb_pcm_pointer(struct snd_pcm_substream *substream
> >  /*
> >   * find a matching audio format
> >   */
> > -static const struct audioformat *
> > +const struct audioformat *
> >  find_format(struct list_head *fmt_list_head, snd_pcm_format_t format,
> >  	    unsigned int rate, unsigned int channels, bool strict_match,
> >  	    struct snd_usb_substream *subs)
> > @@ -147,8 +147,9 @@ find_format(struct list_head *fmt_list_head, snd_pcm_format_t format,
> >  	}
> >  	return found;
> >  }
> > +EXPORT_SYMBOL_GPL(find_format);
> 
> This is a horrible symbol name for a global function, same for the other
> ones in this file.  If you really want to export them, please put them
> in the proper "snd_" prefix namespace, or better yet, use a module
> namespace as well to ensure that we know who is using them.

Yes, please add snd_usb_ prefix for all exported symbols from
USB-audio driver code.

Also, make sure that EXPORT_SYMBOL_GPL() is used for those, too.


thanks,

Takashi