From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934237AbcCNMSp (ORCPT ); Mon, 14 Mar 2016 08:18:45 -0400 Received: from hqemgate14.nvidia.com ([216.228.121.143]:10069 "EHLO hqemgate14.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932148AbcCNMSg (ORCPT ); Mon, 14 Mar 2016 08:18:36 -0400 X-PGP-Universal: processed; by hqnvupgp08.nvidia.com on Mon, 14 Mar 2016 05:17:50 -0700 Date: Mon, 14 Mar 2016 13:18:24 +0100 From: Thierry Reding To: Andy Yan CC: , , , , , , , , , , , Subject: Re: [PATCH 1/2] ARM: multi_v7_defconfig: enable CONFIG_PWM_ROCKCHIP=y Message-ID: <20160314121823.GE22912@ulmo.nvidia.com> References: <1457787029-9168-1-git-send-email-andy.yan@kernel-upstream.org> MIME-Version: 1.0 In-Reply-To: <1457787029-9168-1-git-send-email-andy.yan@kernel-upstream.org> X-NVConfidentiality: public User-Agent: Mutt/1.5.24 (2015-08-30) X-Originating-IP: [10.2.70.46] X-ClientProxiedBy: UKMAIL102.nvidia.com (10.26.138.15) To UKMAIL101.nvidia.com (10.26.138.13) Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="2qXFWqzzG3v1+95a" Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --2qXFWqzzG3v1+95a Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Sat, Mar 12, 2016 at 08:50:29PM +0800, Andy Yan wrote: > All the current rk3066 based boards use pwm modulate vdd_logic > voltage, the board may hang when the system boot and run to a higher > frequency without pwm enabled, so enable it as builtin. I don't understand the rationale here. Surely if the system can't safely switch to a higher frequency because the regulator isn't available, then it should be prevented from switching, shouldn't it? Making this change alone will not prevent users from switching this back to =m on their own. So either you need to add code to prevent a switch to an unsupported frequency in the absence of the regulator, or you need to change the PWM_ROCKCHIP Kconfig option to be bool instead, though the latter is of course a somewhat ugly hack, whereas the former would be a proper fix. Thierry --2qXFWqzzG3v1+95a Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAABCAAGBQJW5qwPAAoJEN0jrNd/PrOhtt4QALiZFFr2nc+JozGycMYVQFIz LJg9B7hC8s8eIYDNjOcJLCO0Msfw+3Tn/lzz92wJtHKQhkO1TiWdnc7Nw044g8UK 6XjW51/+LsBlq8a2vQd48cIwDZpQxn8mZ+newx6lOKAow5EKz3xPPW9+49gsC7g/ 3+W9PAWzsakJxgPlzwLJDKFouRF4VNxs+iMO3DtXB3Agkckd8WWux9tH+ujOx4f2 izPpJwwJca1pczuy2q+ztekiRsoaMR5DRxi0Ji5oCmDN9ZVnYn7oEDSBpkfv7Zeh G7XjL9YAhu2RByUCmG3U+owokHnMsrfgq3IzGQ8QTdP/EutSJjzS6uwwuFQZQqsk 8EPqIgQnd/rh3a+r8YXRNNePutKJE0fh1fdmBK95VwHDdoQl3KY1CMi5TXXsHAby dtTXJG3QdlUvamzIuZe3zzxJf70IO9Rr8ePPBY8jtu7w8sX+nwXLiPD4GW/INJoY TPG3kW05AY2s21xz/IbfsN2ZH9DKvMHTp7+ToLFAd+kUIPzYCCLD1IuDyge5kmJj x1Y6U87dD6dIr6L/goVvI9V57k+cw2BBnIJ8YYt83nz3V5Wjm2YPvqgz8lrph5zj 8fwuNhwD2seY+JYhSwlKsOh04Fkd0OHksDoG3pDa9uzRwX8IruRrOUzdehQrI/73 fGUBZdsTAXznQ5KumqE9 =kKKR -----END PGP SIGNATURE----- --2qXFWqzzG3v1+95a--