From patchwork Sat Feb 16 15:21:16 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guennadi Liakhovetski X-Patchwork-Id: 2151741 Return-Path: X-Original-To: patchwork-linux-sh@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id 99BB33FD4F for ; Sat, 16 Feb 2013 15:21:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753376Ab3BPPVZ (ORCPT ); Sat, 16 Feb 2013 10:21:25 -0500 Received: from moutng.kundenserver.de ([212.227.126.171]:52801 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753322Ab3BPPVY (ORCPT ); Sat, 16 Feb 2013 10:21:24 -0500 Received: from axis700.grange (dslb-188-109-036-115.pools.arcor-ip.net [188.109.36.115]) by mrelayeu.kundenserver.de (node=mreu4) with ESMTP (Nemesis) id 0MUPVW-1UWc990VWc-00R4o8; Sat, 16 Feb 2013 16:21:17 +0100 Received: by axis700.grange (Postfix, from userid 1000) id B08EF40B99; Sat, 16 Feb 2013 16:21:16 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by axis700.grange (Postfix) with ESMTP id A5A6140B98; Sat, 16 Feb 2013 16:21:16 +0100 (CET) Date: Sat, 16 Feb 2013 16:21:16 +0100 (CET) From: Guennadi Liakhovetski X-X-Sender: lyakh@axis700.grange To: linux-mmc@vger.kernel.org cc: devicetree-discuss@lists.ozlabs.org, linux-sh@vger.kernel.org, Magnus Damm , Simon Horman , Arnd Bergmann , Markus Pargmann Subject: [PATCH v5 03/13] mmc: provide a standard MMC device-tree binding parser centrally In-Reply-To: <1360941242-18153-4-git-send-email-g.liakhovetski@gmx.de> Message-ID: References: <1360941242-18153-1-git-send-email-g.liakhovetski@gmx.de> <1360941242-18153-4-git-send-email-g.liakhovetski@gmx.de> MIME-Version: 1.0 X-Provags-ID: V02:K0:KT9vSq4Butn+EUK7vB2BFWq0Ajmu9x2Ws0X0iYZzohz UQNHzThvy9KXIl4YC0P+IixGx2hAe4ZQ1/4miMlKvROxS/K4VW ZGFB+apyL9HFHviKQOhiqX9nbJYVO+/da7gQC+HwU1k2i51IEs 5NhDV5lU57WAzvxuoPiU3xfA3piUWGke1Q77Ru4oDG6dbZGUgV m2DMIgx1Nnu0DVX3YtyU9zCGCHG6gdc4opYMiuoPSIjXFl91Bd SfYTr1SckibAYfZZ4deFDv17XHlskf53ALRKOxSylCcQe61icM kjFuvQVhiVx8U+A5Rfk+6OL82WVVyBV5tSJ2hV8z0ignbc0LkY yGr+IuRWhz79IKZpNgcIzx3POthzK3F56mgA1isa/3kT9gI8w+ re4qcocwjydiw== Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org MMC defines a number of standard DT bindings. Having each driver parse them individually adds code redundancy and is error prone. Provide a standard function to unify the parsing. After all drivers are converted to using it instead of their own parsers, this function can be integrated into mmc_alloc_host(). Signed-off-by: Guennadi Liakhovetski --- v5: 1. fix an uninitialised variable warning. Note, I don't actually know, whether this will fix the error, reported by the kbuild test robot. None of my compilers reports an error there, at most, I've got a warning with one of them, and, surprisingly, it is gone after this change. Surprisingly, because I only add the bus_width initialisation in the error case - exactly as it actually has to be done. In the success case it is assigned set by the function. But the compiler cannot know that! So, I'm surprised... I can only try this version, and see what the robot says now... If it's still unhappy, I'll have to initialise the variable in any case at definition, which I don't want to do, because it isn't really required. 2. replace of_property_read_u32_array(..., 1) with of_property_read_u32() drivers/mmc/core/host.c | 110 ++++++++++++++++++++++++++++++++++++++++++++++ include/linux/mmc/host.h | 1 + 2 files changed, 111 insertions(+), 0 deletions(-) diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index ee2e16b..304e549 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -15,6 +15,8 @@ #include #include #include +#include +#include #include #include #include @@ -23,6 +25,7 @@ #include #include +#include #include "core.h" #include "host.h" @@ -295,6 +298,113 @@ static inline void mmc_host_clk_sysfs_init(struct mmc_host *host) #endif /** + * mmc_of_parse() - parse host's device-tree node + * @host: host, whose node should be parsed. + * + * To keep the rest of the MMC subsystem unaware of the fact, whether DT has + * been used to to instantiate and configure this host instance or not, we + * parse the properties and set respective generic mmc-host flags and + * parameters. + */ +void mmc_of_parse(struct mmc_host *host) +{ + struct device_node *np; + u32 bus_width; + bool explicit_inv_wp, gpio_inv_wp = false; + enum of_gpio_flags flags; + int len, ret, gpio; + + if (!host->parent || !host->parent->of_node) + return; + + np = host->parent->of_node; + + /* "bus-width" is translated to MMC_CAP_*_BIT_DATA flags */ + if (of_property_read_u32(np, "bus-width", &bus_width) < 0) { + dev_dbg(host->parent, + "\"bus-width\" property is missing, assuming 1 bit.\n"); + bus_width = 1; + } + + switch (bus_width) { + case 8: + host->caps |= MMC_CAP_8_BIT_DATA; + /* Hosts, capable of 8-bit transfers can also do 4 bits */ + case 4: + host->caps |= MMC_CAP_4_BIT_DATA; + break; + case 1: + break; + default: + dev_err(host->parent, + "Invalid \"bus-width\" value %ud!\n", bus_width); + } + + /* f_max is obtained from the optional "max-frequency" property */ + of_property_read_u32(np, "max-frequency", &host->f_max); + + /* + * Configure CD and WP pins. They are both by default active low to + * match the SDHCI spec. If GPIOs are provided for CD and / or WP, the + * mmc-gpio helpers are used to attach, configure and use them. If + * polarity inversion is specified in DT, one of MMC_CAP2_CD_ACTIVE_HIGH + * and MMC_CAP2_RO_ACTIVE_HIGH capability-2 flags is set. If the + * "broken-cd" property is provided, the MMC_CAP_NEEDS_POLL capability + * is set. If the "non-removable" property is found, the + * MMC_CAP_NONREMOVABLE capability is set and no card-detection + * configuration is performed. + */ + + /* Parse Card Detection */ + if (of_find_property(np, "non-removable", &len)) { + host->caps |= MMC_CAP_NONREMOVABLE; + } else { + bool explicit_inv_cd, gpio_inv_cd = false; + + explicit_inv_cd = of_property_read_bool(np, "cd-inverted"); + + if (of_find_property(np, "broken-cd", &len)) + host->caps |= MMC_CAP_NEEDS_POLL; + + gpio = of_get_named_gpio_flags(np, "cd-gpios", 0, &flags); + if (gpio_is_valid(gpio)) { + if (!(flags & OF_GPIO_ACTIVE_LOW)) + gpio_inv_cd = true; + + ret = mmc_gpio_request_cd(host, gpio); + if (ret < 0) + dev_err(host->parent, + "Failed to request CD GPIO #%d: %d!\n", + gpio, ret); + else + dev_info(host->parent, "Got CD GPIO #%d.\n", + gpio); + } + + if (explicit_inv_cd ^ gpio_inv_cd) + host->caps2 |= MMC_CAP2_CD_ACTIVE_HIGH; + } + + /* Parse Write Protection */ + explicit_inv_wp = of_property_read_bool(np, "wp-inverted"); + + gpio = of_get_named_gpio_flags(np, "wp-gpios", 0, &flags); + if (gpio_is_valid(gpio)) { + if (!(flags & OF_GPIO_ACTIVE_LOW)) + gpio_inv_wp = true; + + ret = mmc_gpio_request_ro(host, gpio); + if (ret < 0) + dev_err(host->parent, + "Failed to request WP GPIO: %d!\n", ret); + } + if (explicit_inv_wp ^ gpio_inv_wp) + host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH; +} + +EXPORT_SYMBOL(mmc_of_parse); + +/** * mmc_alloc_host - initialise the per-host structure. * @extra: sizeof private data structure * @dev: pointer to host device model structure diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 61a10c1..13c0c8d 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -345,6 +345,7 @@ extern struct mmc_host *mmc_alloc_host(int extra, struct device *); extern int mmc_add_host(struct mmc_host *); extern void mmc_remove_host(struct mmc_host *); extern void mmc_free_host(struct mmc_host *); +void mmc_of_parse(struct mmc_host *host); static inline void *mmc_priv(struct mmc_host *host) {