From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752036AbaEUKZ0 (ORCPT ); Wed, 21 May 2014 06:25:26 -0400 Received: from sauhun.de ([89.238.76.85]:46865 "EHLO pokefinder.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751786AbaEUKZY (ORCPT ); Wed, 21 May 2014 06:25:24 -0400 Date: Wed, 21 May 2014 12:25:15 +0200 From: Wolfram Sang To: Mark Brown Cc: Naveen Krishna Ch , Naveen Krishna Chatradhi , linux-i2c@vger.kernel.org, linux-arm-kernel@lists.infradead.org, "linux-samsung-soc@vger.kernel.org" , sjg@chromium.org, grundler@chromium.org, linux-kernel@vger.kernel.org, cpgs@samsung.com Subject: Re: [PATCH] i2c: exynos5: Initialise Samsung High Speed I2C controller early Message-ID: <20140521102515.GJ2708@katana> References: <1398350916-885-1-git-send-email-ch.naveen@samsung.com> <20140424162558.GB12304@sirena.org.uk> <20140509135153.GM12304@sirena.org.uk> <20140509145425.GP12304@sirena.org.uk> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="pMCBjikF2xGw87uL" Content-Disposition: inline In-Reply-To: <20140509145425.GP12304@sirena.org.uk> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --pMCBjikF2xGw87uL Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, May 09, 2014 at 03:54:25PM +0100, Mark Brown wrote: > On Fri, May 09, 2014 at 08:12:47PM +0530, Naveen Krishna Ch wrote: > > On 9 May 2014 19:21, Mark Brown wrote: > > > On Fri, May 09, 2014 at 05:50:00PM +0530, Naveen Krishna Ch wrote: >=20 > > >> DRM related drivers like DP, FIMD, HDMI, Mixer wants to be probed AS= AP > > >> during the boot. > > >> The real problem comes when, one of these drivers do a regulator_get= (). >=20 > > >> If the physical supply is not enabled/hookedup the regulator_get() = call > > >> assumes that physical supply is present and returns a > > >> "dummy_regulator" (But, not an error). >=20 > > >> Because of which, Display and several other devices fails to work. >=20 > > > These drivers are buggy, if they geniunely expect and handle a missing > > > supply then they should be using regulator_get_optional() to request = the > > > regulator and even if they don't the use of subsys_initcall() is not > > > going to fix anything here - if a dummy regulator is going to be > > > returned the time things are probed won't make a difference. >=20 > ... >=20 > > If all the I2C, SPI, DMA, I2C_TUNNEL, DRM based LCD are all mod_probes() > > DRM drivers are probing a head of the PMIC probe. Which is causing the > > display drivers to get "dummy_regulators" instead of the real supplies. >=20 > No, it really won't - I have no idea what you are doing but it's not > mainline. If you are getting dummy regulators then you don't have a > supply present at all and probe ordering isn't going to make a blind > bit of difference. >=20 > Please provide a specific technical description of the problem you are > seeing in mainline. +1 Unless we have a clear understanding that this is the only acceptable solution in mainline, this is really an out-of-tree patch. --pMCBjikF2xGw87uL Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.15 (GNU/Linux) iQIcBAEBAgAGBQJTfH8LAAoJEBQN5MwUoCm2ucIQALTUkXNNmgTuuIsPE0Wqrfie eJDqbBy5ImwGsGGdAfZBM9Y11kpI9+SHNKMInx0iZCqS5rjodEA0y/cBy+1d6pvZ RcWvGoUTFjkQ22XUQhiSFMioaI4tf0HVrhX+N8XYghGYyw7XlaBbpiWh9IPNxBfG XJigANkBM50p+Gsme2dKk0nKdOwpat3eQF2MbQX1+W99K4tW6KcTFlm57AjfYfdV XESUx1x4JfCNOhag9K9WxANj8kqIg7jwbq6rvpV2xC3z5jLnMlOBbgsGYyB4ATug MBgkWm0LjnSWekIXxKP8mrZtwguhKnvj4eNoaSInBauvXHUk12x5t7ZvA+75jQ0S F1LEzUmlhCbi/JAbVOEXfBmbb0WddcUOHxcM2HLdzU2MaZfR2XpVAE9yrsAGjzhI UT8mMKGhQLmNBULeEuwDtmtA5qbyJst1miHB2WIlTTt3A/azlGzPAhkv+dJDqSqO AGHL64lrWjyl30pcd51EWcstBIWSe+HKtUb326gqFGLxZssMP9QQ/3WhZoC2pHbJ +X+jX9rpxIBOlnNEyDDgnyE5If3zWQR4mSxQtAjoefcO5N5bRRRgq37zXb63YEnt 7358E29wCEHkVXW0PuAR8QlTzwa+D5YpWudUjdOT2SUC/3QHdsEi8Weg6fps0Y/5 oo47lcIJY+Rr1TSq6KZa =V8vQ -----END PGP SIGNATURE----- --pMCBjikF2xGw87uL--