From patchwork Mon Jun 20 23:00:10 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Horman X-Patchwork-Id: 899222 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter2.kernel.org (8.14.4/8.14.4) with ESMTP id p5KN0PO4004498 for ; Mon, 20 Jun 2011 23:00:28 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755995Ab1FTXAZ (ORCPT ); Mon, 20 Jun 2011 19:00:25 -0400 Received: from kirsty.vergenet.net ([202.4.237.240]:60669 "EHLO kirsty.vergenet.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755167Ab1FTXAW (ORCPT ); Mon, 20 Jun 2011 19:00:22 -0400 Received: from joe.akashicho.tokyo.vergenet.net (219-109-213-121.bitcat.net [219.109.213.121]) by kirsty.vergenet.net (Postfix) with ESMTP id 413A624051; Tue, 21 Jun 2011 09:00:18 +1000 (EST) Received: by joe.akashicho.tokyo.vergenet.net (Postfix, from userid 7100) id D3B6328A037; Tue, 21 Jun 2011 08:00:15 +0900 (JST) From: Simon Horman To: linux-mmc@vger.kernel.org, linux-sh@vger.kernel.org Cc: Magnus Damm , Guennadi Liakhovetski , Paul Mundt , Chris Ball , Simon Horman Subject: [PATCH 3/5] mmc: sdhi: Add write16_hook Date: Tue, 21 Jun 2011 08:00:10 +0900 Message-Id: <1308610812-3479-4-git-send-email-horms@verge.net.au> X-Mailer: git-send-email 1.7.4.4 In-Reply-To: <1308610812-3479-1-git-send-email-horms@verge.net.au> References: <1308610812-3479-1-git-send-email-horms@verge.net.au> 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-4.2.6 (demeter2.kernel.org [140.211.167.43]); Mon, 20 Jun 2011 23:00:28 +0000 (UTC) Some controllers require waiting for the bus to become idle before writing to some registers. I have implemented this by adding a hook to sd_ctrl_write16() and implementing a hook for SDHI which waits for the bus to become idle. Cc: Guennadi Liakhovetski Cc: Magnus Damm Signed-off-by: Simon Horman --- Dependencies: "mmc: tmio: Share register access functions" v2: * Include linux/delay.h instead of asm/delay.h * Skip write if sh_mobile_sdhi_wait_idle() times out - The bus will probably be in an inconsistent state and writing may lock up the bus * Only set hook if TMIO_MMC_HAS_IDLE_WAIT is set in platform data rather than checking for TMIO_MMC_HAS_IDLE_WAIT each time the hook is called. --- drivers/mmc/host/sh_mobile_sdhi.c | 36 ++++++++++++++++++++++++++++++++++++ drivers/mmc/host/tmio_mmc.h | 5 +++++ include/linux/mfd/tmio.h | 8 ++++++++ include/linux/mmc/tmio.h | 1 + 4 files changed, 50 insertions(+), 0 deletions(-) diff --git a/drivers/mmc/host/sh_mobile_sdhi.c b/drivers/mmc/host/sh_mobile_sdhi.c index b365429..c8b1f6b 100644 --- a/drivers/mmc/host/sh_mobile_sdhi.c +++ b/drivers/mmc/host/sh_mobile_sdhi.c @@ -26,6 +26,7 @@ #include #include #include +#include #include "tmio_mmc.h" @@ -55,6 +56,39 @@ static int sh_mobile_sdhi_get_cd(struct platform_device *pdev) return -ENOSYS; } +static int sh_mobile_sdhi_wait_idle(struct tmio_mmc_host *host) +{ + int timeout = 1000; + + while (--timeout && !(sd_ctrl_read16(host, CTL_STATUS2) & (1 << 13))) + udelay(1); + + if (!timeout) { + dev_warn(host->pdata->dev, "timeout waiting for SD bus idle\n"); + return -EBUSY; + } + + return 0; +} + +static int sh_mobile_sdhi_write16_hook(struct tmio_mmc_host *host, int addr) +{ + switch (addr) + { + case CTL_SD_CMD: + case CTL_STOP_INTERNAL_ACTION: + case CTL_XFER_BLK_COUNT: + case CTL_SD_CARD_CLK_CTL: + case CTL_SD_XFER_LEN: + case CTL_SD_MEM_CARD_OPT: + case CTL_TRANSACTION_CTL: + case CTL_DMA_ENABLE: + return sh_mobile_sdhi_wait_idle(host); + } + + return 0; +} + static int __devinit sh_mobile_sdhi_probe(struct platform_device *pdev) { struct sh_mobile_sdhi *priv; @@ -86,6 +120,8 @@ static int __devinit sh_mobile_sdhi_probe(struct platform_device *pdev) mmc_data->hclk = clk_get_rate(priv->clk); mmc_data->set_pwr = sh_mobile_sdhi_set_pwr; mmc_data->get_cd = sh_mobile_sdhi_get_cd; + if (mmc_data->flags & TMIO_MMC_HAS_IDLE_WAIT) + mmc_data->write16_hook = sh_mobile_sdhi_write16_hook; mmc_data->capabilities = MMC_CAP_MMC_HIGHSPEED; if (p) { mmc_data->flags = p->tmio_flags; diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h index 0c22df0..211ef6e 100644 --- a/drivers/mmc/host/tmio_mmc.h +++ b/drivers/mmc/host/tmio_mmc.h @@ -153,6 +153,11 @@ static inline u32 sd_ctrl_read32(struct tmio_mmc_host *host, int addr) static inline void sd_ctrl_write16(struct tmio_mmc_host *host, int addr, u16 val) { + /* If there is a hook and it returns non-zero then there + * is an error and the write should be skipped + */ + if (host->pdata->write16_hook && host->pdata->write16_hook(host, addr)) + return; writew(val, host->ctl + (addr << host->bus_shift)); } diff --git a/include/linux/mfd/tmio.h b/include/linux/mfd/tmio.h index 5a90266..0dc9804 100644 --- a/include/linux/mfd/tmio.h +++ b/include/linux/mfd/tmio.h @@ -68,6 +68,11 @@ * controller and report the event to the driver. */ #define TMIO_MMC_HAS_COLD_CD (1 << 3) +/* + * Some controllers require waiting for the SD bus to become + * idle before writing to some registers. + */ +#define TMIO_MMC_HAS_IDLE_WAIT (1 << 4) int tmio_core_mmc_enable(void __iomem *cnf, int shift, unsigned long base); int tmio_core_mmc_resume(void __iomem *cnf, int shift, unsigned long base); @@ -80,6 +85,8 @@ struct tmio_mmc_dma { int alignment_shift; }; +struct tmio_mmc_host; + /* * data for the MMC controller */ @@ -94,6 +101,7 @@ struct tmio_mmc_data { void (*set_pwr)(struct platform_device *host, int state); void (*set_clk_div)(struct platform_device *host, int state); int (*get_cd)(struct platform_device *host); + int (*write16_hook)(struct tmio_mmc_host *host, int addr); }; static inline void tmio_mmc_cd_wakeup(struct tmio_mmc_data *pdata) diff --git a/include/linux/mmc/tmio.h b/include/linux/mmc/tmio.h index 0a6e40d..f235757 100644 --- a/include/linux/mmc/tmio.h +++ b/include/linux/mmc/tmio.h @@ -21,6 +21,7 @@ #define CTL_XFER_BLK_COUNT 0xa #define CTL_RESPONSE 0x0c #define CTL_STATUS 0x1c +#define CTL_STATUS2 0x1e #define CTL_IRQ_MASK 0x20 #define CTL_SD_CARD_CLK_CTL 0x24 #define CTL_SD_XFER_LEN 0x26