From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757940Ab3BGKrG (ORCPT ); Thu, 7 Feb 2013 05:47:06 -0500 Received: from service87.mimecast.com ([91.220.42.44]:36743 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757316Ab3BGKrC convert rfc822-to-8bit (ORCPT ); Thu, 7 Feb 2013 05:47:02 -0500 Date: Thu, 7 Feb 2013 10:46:56 +0000 From: Mark Rutland To: "Manjunathappa, Prakash" Cc: "linux-mmc@vger.kernel.org" , "mporter@ti.com" , "davinci-linux-open-source@linux.davincidsp.com" , "cjb@laptop.org" , "linux@arm.linux.org.uk" , "linux-doc@vger.kernel.org" , "devicetree-discuss@lists.ozlabs.org" , "nsekhar@ti.com" , "linux-kernel@vger.kernel.org" , "rob.herring@calxeda.com" , "hs@denx.de" , "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH v2 2/3] mmc: davinci_mmc: add DT support Message-ID: <20130207104656.GE16987@e106331-lin.cambridge.arm.com> References: <1360223825-23929-1-git-send-email-prakash.pm@ti.com> <1360223825-23929-3-git-send-email-prakash.pm@ti.com> MIME-Version: 1.0 In-Reply-To: <1360223825-23929-3-git-send-email-prakash.pm@ti.com> User-Agent: Mutt/1.5.20 (2009-06-14) X-OriginalArrivalTime: 07 Feb 2013 10:46:57.0388 (UTC) FILETIME=[736C1AC0:01CE0520] X-MC-Unique: 113020710470005201 Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: 8BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, I have a couple of comments on the dt bindings and the way it's parsed. On Thu, Feb 07, 2013 at 07:57:04AM +0000, Manjunathappa, Prakash wrote: > Adds device tree support for davinci_mmc. Also add binding documentation. > Tested in non-dma PIO mode and without GPIO card_detect/write_protect > option because of dependencies on EDMA and GPIO module DT support. > > Signed-off-by: Manjunathappa, Prakash > Cc: linux-mmc@vger.kernel.org > Cc: linux-arm-kernel@lists.infradead.org > Cc: linux-kernel@vger.kernel.org > Cc: davinci-linux-open-source@linux.davincidsp.com > Cc: devicetree-discuss@lists.ozlabs.org > Cc: cjb@laptop.org > Cc: Sekhar Nori > Cc: mporter@ti.com > --- > Since v1: > Modified DT parse function to take default values and accomodate controller > version in compatible field. > > .../devicetree/bindings/mmc/davinci_mmc.txt | 30 ++++++++ > drivers/mmc/host/davinci_mmc.c | 70 +++++++++++++++++++- > 2 files changed, 99 insertions(+), 1 deletions(-) > create mode 100644 Documentation/devicetree/bindings/mmc/davinci_mmc.txt > > diff --git a/Documentation/devicetree/bindings/mmc/davinci_mmc.txt b/Documentation/devicetree/bindings/mmc/davinci_mmc.txt > new file mode 100644 > index 0000000..6717ab1 > --- /dev/null > +++ b/Documentation/devicetree/bindings/mmc/davinci_mmc.txt > @@ -0,0 +1,30 @@ > +* TI Highspeed MMC host controller for DaVinci > + > +The Highspeed MMC Host Controller on TI DaVinci family > +provides an interface for MMC, SD and SDIO types of memory cards. > + > +This file documents the properties used by the davinci_mmc driver. > + > +Required properties: > +- compatible: > + Should be "ti,davinci-mmc-da830": for da830, da850, dm365 > + Should be "ti,davinci-mmc-dm355": for dm355, dm644x > + > +Optional properties: > +- bus-width: Number of data lines, can be <4>, or <8>, default <1> > +- max-frequency: Maximum operating clock frequency, default 25MHz. > +- mmc-cap-mmc-highspeed: Indicates support for MMC in high speed mode > +- mmc-cap-sd-highspeed: Indicates support for SD in high speed mode I thought the last two were derivable from max-frequency? https://lkml.org/lkml/2012/10/15/231 [...] > +static struct davinci_mmc_config > + *mmc_parse_pdata(struct platform_device *pdev) > { > + struct device_node *np; > struct davinci_mmc_config *pdata = pdev->dev.platform_data; > + const struct of_device_id *match = > + of_match_device(of_match_ptr(davinci_mmc_dt_ids), &pdev->dev); > + u32 data; > + > + np = pdev->dev.of_node; > + if (!np) > + return pdata; > + > + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); > + if (!pdata) { > + dev_err(&pdev->dev, "Failed to allocate memory for struct davinci_mmc_config\n"); > + goto nodata; > + } > + > + if (match->data) > + pdata->version = (u8)((int)match->data); > + > + of_property_read_u32(np, "max-frequency", &pdata->max_freq); > + if (!pdata->max_freq) > + dev_info(&pdev->dev, "'max-frequency' property not specified, defaulting to 25MHz\n"); > + > + if (of_get_property(np, "mmc-cap-mmc-highspeed", NULL)) > + pdata->caps |= MMC_CAP_MMC_HIGHSPEED; > + if (of_get_property(np, "mmc-cap-sd-highspeed", NULL)) > + pdata->caps |= MMC_CAP_SD_HIGHSPEED; If these aren't derivable from max-frequency, you could use of_property_read_bool to make this clearer. > + > + of_property_read_u32(np, "bus-width", &data); > + switch (data) { > + case 0: Judging by the binding doc, should this be 1 rather than 0? > + case 4: > + case 8: > + pdata->wires = data; > + break; > + default: > + pdata->wires = 1; > + dev_info(&pdev->dev, "Unsupported buswidth, defaulting to 1 bit\n"); > + } > +nodata: > + return pdata; > +} > + > +static int __init davinci_mmcsd_probe(struct platform_device *pdev) > +{ > + struct davinci_mmc_config *pdata = NULL; > struct mmc_davinci_host *host = NULL; > struct mmc_host *mmc = NULL; > struct resource *r, *mem = NULL; > int ret = 0, irq = 0; > size_t mem_size; > > + pdata = mmc_parse_pdata(pdev); > + if (pdata == NULL) { > + dev_err(&pdev->dev, "Can not get platform data\n"); > + return -ENOENT; > + } > + > /* REVISIT: when we're fully converted, fail if pdata is NULL */ This comment can presumably disappear judging by the lines above? [...] Thanks, Mark.