From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wolfram Sang Subject: Re: [PATCH] i2c: sirf: move driver init from module_init to subsys_initcall Date: Mon, 10 Jun 2013 15:45:36 +0200 Message-ID: <20130610134535.GB2987@katana> References: <1368672607-5536-1-git-send-email-Baohua.Song@csr.com> <20130516093846.GA2927@katana> <20130525201032.GD32043@sirena.org.uk> <20130527121658.GA3660@sirena.org.uk> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="Bn2rw/3z4jIqBvZU" Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Barry Song <21cnbao-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> Cc: Mark Brown , workgroup.linux-kQvG35nSl+M@public.gmane.org, Xiaomeng Hou , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Barry Song List-Id: linux-i2c@vger.kernel.org --Bn2rw/3z4jIqBvZU Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, May 27, 2013 at 11:36:14PM +0800, Barry Song wrote: > 2013/5/27 Mark Brown : > > On Mon, May 27, 2013 at 09:54:56AM +0800, Barry Song wrote: > > > >> Mark, the case is not that deferred probing is slow or not. deferred > >> probing is pretty good. > >> the case is that we want to i2c and media connected with i2c probed > >> earlier than other devices. > >> in auto infotainment devices, we actually do some hacking in kernel > >> that makes rear view work earlier than other device driver > >> initialization with a kernel thread which take care of backing-car > >> policy not only mechanism. that means, we make camera work to see > >> backview image even earlier than other drivers' initialization. > >> we don't want media deferred to wait for i2c. we want make some early > >> jobs ready earlier. > > > > So this change makes no practical difference in mainline and exists to > > support out of tree hacks for performance? It doesn't seem like that > > big a patch to carry along with the out of tree stuff... >=20 > yes. but i don't think we are easy to make those out-of-mainline hacks > be in mainline. but this patch is both ok to mainline and local tree. > making local tree and mainline same as many as possible decreases our > maintaince efforts totally. I understand that, yet I agree with Mark. The mainline idea is to use deferred probing to make sure all components come up correctly. In fact, I wish for patches removing subsys_initcall with deferred probing. --Bn2rw/3z4jIqBvZU Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJRtdh/AAoJEBQN5MwUoCm2QN8QAJv/1gsEURIttsuY1ei5DJDF lYDJCnRxkrVjR8FsykzLxWzwGm4E+27ojbc9ClVSpnRcBVcVtNvaGiPEtZr4/l2C y/2hzfP4RU/1pHIfWyQ5u2p0g1kZPX64w2klnQNb5ZT5YlWN2l4xDXF/qZhGxAio AdCVdtKmqog8K/h4QY7+FKa/rGInLX/Em2VTfxHuZT0rFnc/2JqDFmOWkz3GsC7p QHcNRSg+Toh+NfJ7V86RHSU59Y8vAIngGdlWNDeR7xigPOD/T5qwSOUVIiNe2yF4 mYj4HgKkpaLqt2xuxF1wwGhr/Ol3mQaOofYyencVhICx0NQvtj/ZH6hqGGgyoEq/ s88oz45fE+xB2P8JT0aPdrSR6PkrCP/l2eAyDZPqP7ICAi6ZfGfmpKnqGU+Bvs6B H+H6ktuHJ280tX5tOghPo5pRHyVTokrO0EorElf1Hyd4n4p0e2bItADuiNK60yP8 shIVr9XyKKEYff5hbtuM3pUaxjBP4Jc3/KYSJ5sOhmt3rbKWhhx0WeTZhqQ0IrF0 7hBDAsWsApx6qG8ZwXcj7e5Hj2Qi4FlCK3ze1PMhTnAHmvJHF2IjURG3W6lTokuV /cS23NjAvxSqZIlfm/OuXtecpju8Awf12Xzyo3YSEb+xTsK4heSM7Y8Iw8jXNnlb jWKLb4Zw7jsfm23qPkPI =XBh7 -----END PGP SIGNATURE----- --Bn2rw/3z4jIqBvZU--