From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756570AbcANR1j (ORCPT ); Thu, 14 Jan 2016 12:27:39 -0500 Received: from pandora.arm.linux.org.uk ([78.32.30.218]:37934 "EHLO pandora.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755131AbcANR0P (ORCPT ); Thu, 14 Jan 2016 12:26:15 -0500 Date: Thu, 14 Jan 2016 17:25:49 +0000 From: Russell King - ARM Linux To: Sebastian Reichel Cc: Kishon Vijay Abraham I , Ulf Hansson , ivo.g.dimitrov.75@gmail.com, aaro.koskinen@iki.fi, Tony Lindgren , nsekhar@ti.com, khilman@kernel.org, linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, NeilBrown , pavel@ucw.cz, pali.rohar@gmail.com, linux-omap@vger.kernel.org, patrikbachan@gmail.com, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] mmc: host: omap_hsmmc: add a verbose print to enable CONFIG_REGULATOR_PBIAS Message-ID: <20160114172549.GC5783@n2100.arm.linux.org.uk> References: <1452762920-2588-1-git-send-email-kishon@ti.com> <20160114120706.GA12774@earth> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160114120706.GA12774@earth> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 14, 2016 at 01:07:06PM +0100, Sebastian Reichel wrote: > Hi, > > On Thu, Jan 14, 2016 at 02:45:20PM +0530, Kishon Vijay Abraham I wrote: > > Since v4.3+, CONFIG_REGULATOR_PBIAS should be enabled (for platforms that > > have PBIAS regulator) in order for MMC1 to work. > > > > Add a more verbose print to help enable CONFIG_REGULATOR_PBIAS for users > > using a olddefconfig or a custom .config. > > > > Signed-off-by: Kishon Vijay Abraham I > > --- > > drivers/mmc/host/omap_hsmmc.c | 5 ++++- > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c > > index 7fb0753..7086bd6 100644 > > --- a/drivers/mmc/host/omap_hsmmc.c > > +++ b/drivers/mmc/host/omap_hsmmc.c > > @@ -503,8 +503,11 @@ static int omap_hsmmc_reg_get(struct omap_hsmmc_host *host) > > host->pbias = devm_regulator_get_optional(host->dev, "pbias"); > > if (IS_ERR(host->pbias)) { > > ret = PTR_ERR(host->pbias); > > - if ((ret != -ENODEV) && host->dev->of_node) > > + if ((ret != -ENODEV) && host->dev->of_node) { > > + dev_err(host->dev, > > + "SD card detect fail? enable CONFIG_REGULATOR_PBIAS\n"); > > return ret; > > + } > > dev_dbg(host->dev, "unable to get pbias regulator %ld\n", > > PTR_ERR(host->pbias)); > > host->pbias = NULL; > > > Is there a good reason against adding "depends on REGULATOR_PBIAS" > to MMC_OMAP_HS? There are very good reasons not to do this: that will result in configurations where MMC_OMAP_HS was set but without REGULATOR_PBIAS ending up with MMC_OMAP_HS being disabled. That doesn't help the root problem, which is "why has the kernel boot regressed for my previous working configuration?" The solution proposed here adds a message to the boot which points out fair and square what needs to be done to rectify the boot failure. Adding a dependency just brings up the question "where has my MMC driver gone?" -- RMK's Patch system: http://www.arm.linux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net.