From patchwork Sun Nov 21 19:17:09 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Philip Rakity X-Patchwork-Id: 346041 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id oALJHUXx012375 for ; Sun, 21 Nov 2010 19:17:31 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754713Ab0KUTR2 (ORCPT ); Sun, 21 Nov 2010 14:17:28 -0500 Received: from na3sys009aog109.obsmtp.com ([74.125.149.201]:49535 "HELO na3sys009aog109.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752790Ab0KUTR1 convert rfc822-to-8bit (ORCPT ); Sun, 21 Nov 2010 14:17:27 -0500 Received: from source ([65.219.4.129]) (using TLSv1) by na3sys009aob109.postini.com ([74.125.148.12]) with SMTP ID DSNKTOlwQgAHtuKGuXjtpR3QNr094CqbV/XJ@postini.com; Sun, 21 Nov 2010 11:17:27 PST Received: from SC-vEXCH3.marvell.com ([10.93.76.133]) by SC-OWA01.marvell.com ([10.93.76.21]) with mapi; Sun, 21 Nov 2010 11:17:11 -0800 From: Philip Rakity To: Chris Ball CC: Wolfram Sang , "linux-mmc@vger.kernel.org" Date: Sun, 21 Nov 2010 11:17:09 -0800 Subject: Re: [RFC] sdhci: 8 bit bus width changes Thread-Topic: [RFC] sdhci: 8 bit bus width changes Thread-Index: AcuJsLKFo85EnBt3TMKeCwVZOUowLg== Message-ID: <06A44983-1A70-4715-86AF-66C08DD381C0@marvell.com> References: <20101119214002.GA19272@void.printf.net> <20101119215333.GB19272@void.printf.net> <20101120123553.GA11936@pengutronix.de> <20101120182423.GA31030@void.printf.net> In-Reply-To: <20101120182423.GA31030@void.printf.net> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US MIME-Version: 1.0 Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter1.kernel.org [140.211.167.41]); Sun, 21 Nov 2010 19:17:31 +0000 (UTC) diff --git a/arch/arm/plat-pxa/include/plat/sdhci.h b/arch/arm/plat-pxa/include/plat/sdhci.h index e49c5b6..e85b58f 100644 --- a/arch/arm/plat-pxa/include/plat/sdhci.h +++ b/arch/arm/plat-pxa/include/plat/sdhci.h @@ -17,6 +17,9 @@ /* Require clock free running */ #define PXA_FLAG_DISABLE_CLOCK_GATING (1<<0) +/* board design supports 8 bit data on SD/SDIO BUS */ +#define PXA_FLAG_SD_8_BIT_CAPABLE_SLOT (1<<2) + /* * struct pxa_sdhci_platdata() - Platform device data for PXA SDHCI * @max_speed: the maximum speed supported diff --git a/drivers/mmc/host/sdhci-pxa.c b/drivers/mmc/host/sdhci-pxa.c index fc406ac..f609f4a 100644 --- a/drivers/mmc/host/sdhci-pxa.c +++ b/drivers/mmc/host/sdhci-pxa.c @@ -141,6 +141,10 @@ static int __devinit sdhci_pxa_probe(struct platform_device *pdev) if (pdata->quirks) host->quirks |= pdata->quirks; + /* if slot design supports 8 bit data - indicate this */ + if (pdata->flags & PXA_FLAG_SD_8_BIT_CAPABLE_SLOT) + host->mmc->caps |= MMC_CAP_8_BIT_DATA; + ret = sdhci_add_host(host); if (ret) { dev_err(&pdev->dev, "failed to add host\n"); diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 154cbf8..03c801b 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -1185,17 +1185,31 @@ static void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) if (host->ops->platform_send_init_74_clocks) host->ops->platform_send_init_74_clocks(host, ios->power_mode); - ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL); - - if (ios->bus_width == MMC_BUS_WIDTH_8) - ctrl |= SDHCI_CTRL_8BITBUS; - else - ctrl &= ~SDHCI_CTRL_8BITBUS; + /* + * If your platform has 8-bit width support but is not a v3 controller, + * or if it requires special setup code, you should implement that in + * platform_8bit_width(). + */ + if (host->ops->platform_8bit_width) + host->ops->platform_8bit_width(host, ios->bus_width); + else { + ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL); + if (ios->bus_width == MMC_BUS_WIDTH_8) { + ctrl &= ~SDHCI_CTRL_4BITBUS; + if (host->version >= SDHCI_SPEC_300) + ctrl |= SDHCI_CTRL_8BITBUS; + } else { + if (host->version >= SDHCI_SPEC_300) + ctrl &= ~SDHCI_CTRL_8BITBUS; + if (ios->bus_width == MMC_BUS_WIDTH_4) + ctrl |= SDHCI_CTRL_4BITBUS; + else + ctrl &= ~SDHCI_CTRL_4BITBUS; + } + sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL); + } - if (ios->bus_width == MMC_BUS_WIDTH_4) - ctrl |= SDHCI_CTRL_4BITBUS; - else - ctrl &= ~SDHCI_CTRL_4BITBUS; + ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL); if ((ios->timing == MMC_TIMING_SD_HS || ios->timing == MMC_TIMING_MMC_HS) @@ -1855,11 +1869,22 @@ int sdhci_add_host(struct sdhci_host *host) mmc->f_min = host->max_clk / SDHCI_MAX_DIV_SPEC_300; else mmc->f_min = host->max_clk / SDHCI_MAX_DIV_SPEC_200; + mmc->f_max = host->max_clk; mmc->caps |= MMC_CAP_SDIO_IRQ; - if (!(host->quirks & SDHCI_QUIRK_FORCE_1_BIT_DATA)) - mmc->caps |= MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA; + /* + * A controller may support 8-bit width, but the board itself + * might not have the pins brought out. So, boards that support + * 8-bit width should set the MMC_CAP_8_BIT_DATA and we won't assume + * that devices without the quirk can use 8-bit width. + * + * set mmc->caps |= MMC_CAP_8_BIT_DATA in platfrom code + * before call for_add_host to enable 8 bit support + */ + if (!(host->quirks & SDHCI_QUIRK_FORCE_1_BIT_DATA)) { + mmc->caps |= MMC_CAP_4_BIT_DATA; + } if (caps & SDHCI_CAN_DO_HISPD) mmc->caps |= MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED; diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h index d52a716..ff18eaa 100644 --- a/drivers/mmc/host/sdhci.h +++ b/drivers/mmc/host/sdhci.h @@ -76,7 +76,7 @@ #define SDHCI_CTRL_ADMA1 0x08 #define SDHCI_CTRL_ADMA32 0x10 #define SDHCI_CTRL_ADMA64 0x18 -#define SDHCI_CTRL_8BITBUS 0x20 +#define SDHCI_CTRL_8BITBUS 0x20 #define SDHCI_POWER_CONTROL 0x29 #define SDHCI_POWER_ON 0x01 @@ -215,6 +215,8 @@ struct sdhci_ops { unsigned int (*get_max_clock)(struct sdhci_host *host); unsigned int (*get_min_clock)(struct sdhci_host *host); unsigned int (*get_timeout_clock)(struct sdhci_host *host); + int (*platform_8bit_width)(struct sdhci_host *host, + int width); void (*platform_send_init_74_clocks)(struct sdhci_host *host, u8 power_mode); unsigned int (*get_ro)(struct sdhci_host *host);