From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751976AbbFDJCi (ORCPT ); Thu, 4 Jun 2015 05:02:38 -0400 Received: from metis.ext.pengutronix.de ([92.198.50.35]:38594 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752102AbbFDJCa (ORCPT ); Thu, 4 Jun 2015 05:02:30 -0400 Date: Thu, 4 Jun 2015 11:02:12 +0200 From: Sascha Hauer To: Chaotian Jing Cc: Rob Herring , Matthias Brugger , Chris Ball , Ulf Hansson , Mark Rutland , James Liao , srv_heupstream@mediatek.com, Arnd Bergmann , devicetree@vger.kernel.org, Hongzhou Yang , Catalin Marinas , bin.zhang@mediatek.com, linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, Will Deacon , linux-gpio@vger.kernel.org, linux-mediatek@lists.infradead.org, Sascha Hauer , "Joe.C" , Eddie Huang , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v4 2/7] mmc: mediatek: Add Mediatek MMC driver Message-ID: <20150604090212.GY6325@pengutronix.de> References: <1432017411-2996-1-git-send-email-chaotian.jing@mediatek.com> <1432017411-2996-3-git-send-email-chaotian.jing@mediatek.com> <20150519111558.GD6325@pengutronix.de> <1433386443.3304.2.camel@mhfsdcap03> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1433386443.3304.2.camel@mhfsdcap03> X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-IRC: #ptxdist @freenode X-Accept-Language: de,en X-Accept-Content-Type: text/plain X-Uptime: 11:01:52 up 79 days, 20:53, 104 users, load average: 0.06, 0.11, 0.13 User-Agent: Mutt/1.5.21 (2010-09-15) X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: sha@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 04, 2015 at 10:54:03AM +0800, Chaotian Jing wrote: > On Tue, 2015-05-19 at 13:15 +0200, Sascha Hauer wrote: > > On Tue, May 19, 2015 at 02:36:46PM +0800, Chaotian Jing wrote: > > > Add Mediatek MMC driver code > > > Support eMMC/SD/SDIO > > > > > > Signed-off-by: Chaotian Jing > > > --- > > > drivers/mmc/host/Kconfig | 8 + > > > drivers/mmc/host/Makefile | 1 + > > > drivers/mmc/host/mtk-sd.c | 1422 +++++++++++++++++++++++++++++++++++++++++++++ > > > 3 files changed, 1431 insertions(+) > > > create mode 100644 drivers/mmc/host/mtk-sd.c > > > > > > + > > > + host->src_clk = devm_clk_get(&pdev->dev, "source"); > > > + if (IS_ERR(host->src_clk)) { > > > + ret = PTR_ERR(host->src_clk); > > > + goto host_free; > > > + } > > > + > > > + host->h_clk = devm_clk_get(&pdev->dev, "hclk"); > > > + if (IS_ERR(host->h_clk)) { > > > + /* host->h_clk is optional, Only for MSDC0/3 at MT8173 */ > > > + dev_dbg(&pdev->dev, > > > + "Invalied hclk from the device tree!\n"); > > > + } > > > > s/Invalied/Invalid/ > > > > According to my reference manual the controller always needs a hclk. It > > seems on some controllers it is just not software controllable. If > > that's the case you should always provide a hclk to the driver and make > > this clock mandatory. > For MT8173, MSDC1, MSDC2's HCLK are in Infra, software cannot control > it. So just set the HCLK to clk_null ? Yes, please. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |