From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lars-Peter Clausen Subject: Re: [alsa-devel] [RFC PATCH] ASoC: Modify check condition of multiple bindings of components Date: Thu, 15 Oct 2015 15:26:17 +0200 Message-ID: <561FA979.6030407@metafoo.de> References: <1444743477-48819-1-git-send-email-koro.chen@mediatek.com> <561D0AA9.5080702@metafoo.de> <1444745902.26493.2.camel@mtksdaap41> <561D1843.1020007@metafoo.de> <1444785549.26493.12.camel@mtksdaap41> <561E1991.1050705@metafoo.de> <20151015121035.GE14956@sirena.org.uk> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="JPKCCjUqCRPjWFBVK5mJN5uJ8IiahrslM" Return-path: In-Reply-To: <20151015121035.GE14956@sirena.org.uk> Sender: linux-kernel-owner@vger.kernel.org To: Mark Brown Cc: Koro Chen , alsa-devel@alsa-project.org, srv_heupstream@mediatek.com, tiwai@suse.de, s.hauer@pengutronix.de, linux-kernel@vger.kernel.org, lgirdwood@gmail.com, linux-mediatek@lists.infradead.org, p.zabel@pengutronix.de, linux-arm-kernel@lists.infradead.org List-Id: alsa-devel@alsa-project.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --JPKCCjUqCRPjWFBVK5mJN5uJ8IiahrslM Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable On 10/15/2015 02:10 PM, Mark Brown wrote: > On Wed, Oct 14, 2015 at 11:00:01AM +0200, Lars-Peter Clausen wrote: >=20 >> It was never intended that it is possible to bind a component to multi= ple >> cards. That it was possible was a bug that was overlooked and some peo= ple >> tried to do it which caused apparently random crashes later on, caused= by >> the data structure corruption. This is why we added the check to catch= this >> kind of mistake early and to avoid the crashes. >=20 > This is true, but I do think it's something that we should have some > story on supporting for some of this hardware that has a bunch of > channels in one IP block that can't really interact with each other. > It's going to make it a lot easier for people to think about the > hardware and how to describe it. I'm not saying we shouldn't support it, just that we can't support it wit= h the current code. And adding support for it will require a fair bit of restructuring. If a hardware block as multiple independent channels the best approach in= my opinion is to register multiple components (Which we can't do at the mome= nt, because there can only be one component per device). From a framework poi= nt of view there is no difference between a single device with multiple independent channels and multiple independent devices with one channel ea= ch. Both have the same logical topology. - Lars --JPKCCjUqCRPjWFBVK5mJN5uJ8IiahrslM Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJWH6l5AAoJEOj3aLScRbOZ0DYP+wQ0qvOkYDWiFoPX3OZY+/Gi ykBQ5X9iOpalWxVsCh0k++4YvisZyGqlPu65mUFtvFLcdAnluv4bADw7wALADV4H BeDtwr0GN2xNab+uYsqae4F2cwqwMM9c7Jn9Tok7k9Hz8pRLNdi628xQOPjrDk5+ SmI231WT8L6RlOOxsESiEMjLpzDLMZDSDNn7KpjkxI6Hlw0kA4UEtjqoSit5rj0n 7X1pI87eWDquceSr/xpXEa7o/Q+qU6DrUnd07cRXrJOoWbVPNeiXJhPyNrALzb3P vM8Dg6VE3ZoXE5aAd7HADIy2d9QxY2VfntbFh6Ttzky353a9boKEbacehHGWHuLp j7UCgM+XJp+kQxD+3QCM/bHEUdzgmljf9LFW7MqDnPO/WT5o6wXjDoH7K6Mg+AKg cou7RnploYjBMon91ZRWTslLRP8U35HzJM95j+BI/aokNfEX6iucQ2+bwr4jHzbm A50eMjaFjQbKhx7pY89A7KutPP6iVOqwcskO8IQl52KQftdnwaxpNM0Uywpzov4m QIdSBt2NtQvJmmDcwi6EhlWnRE8SxqsPt47Ar8mL1CaLI58xtsphxOAVy1pZy8Tj s5brEiNZGRJz0FFT1xWBHZ6FNwJWa9EgQllKyKn4xMxIUPZCCbEgbkMzqy9m/sqJ de27BWIHDp1aD+uiNV34 =o2qz -----END PGP SIGNATURE----- --JPKCCjUqCRPjWFBVK5mJN5uJ8IiahrslM-- From mboxrd@z Thu Jan 1 00:00:00 1970 From: lars@metafoo.de (Lars-Peter Clausen) Date: Thu, 15 Oct 2015 15:26:17 +0200 Subject: [alsa-devel] [RFC PATCH] ASoC: Modify check condition of multiple bindings of components In-Reply-To: <20151015121035.GE14956@sirena.org.uk> References: <1444743477-48819-1-git-send-email-koro.chen@mediatek.com> <561D0AA9.5080702@metafoo.de> <1444745902.26493.2.camel@mtksdaap41> <561D1843.1020007@metafoo.de> <1444785549.26493.12.camel@mtksdaap41> <561E1991.1050705@metafoo.de> <20151015121035.GE14956@sirena.org.uk> Message-ID: <561FA979.6030407@metafoo.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 10/15/2015 02:10 PM, Mark Brown wrote: > On Wed, Oct 14, 2015 at 11:00:01AM +0200, Lars-Peter Clausen wrote: > >> It was never intended that it is possible to bind a component to multiple >> cards. That it was possible was a bug that was overlooked and some people >> tried to do it which caused apparently random crashes later on, caused by >> the data structure corruption. This is why we added the check to catch this >> kind of mistake early and to avoid the crashes. > > This is true, but I do think it's something that we should have some > story on supporting for some of this hardware that has a bunch of > channels in one IP block that can't really interact with each other. > It's going to make it a lot easier for people to think about the > hardware and how to describe it. I'm not saying we shouldn't support it, just that we can't support it with the current code. And adding support for it will require a fair bit of restructuring. If a hardware block as multiple independent channels the best approach in my opinion is to register multiple components (Which we can't do at the moment, because there can only be one component per device). From a framework point of view there is no difference between a single device with multiple independent channels and multiple independent devices with one channel each. Both have the same logical topology. - Lars -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: OpenPGP digital signature URL: