From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chunyan Zhang Subject: [PATCH V4 1/7] mmc: sdhci: add sd host v4 mode Date: Mon, 23 Jul 2018 18:08:22 +0800 Message-ID: <1532340508-8749-2-git-send-email-zhang.chunyan@linaro.org> References: <1532340508-8749-1-git-send-email-zhang.chunyan@linaro.org> Return-path: In-Reply-To: <1532340508-8749-1-git-send-email-zhang.chunyan@linaro.org> Sender: linux-kernel-owner@vger.kernel.org To: Ulf Hansson , Adrian Hunter Cc: linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, Orson Zhai , Baolin Wang , Billows Wu , Jason Wu , zhang.lyra@gmail.com List-Id: linux-mmc@vger.kernel.org For SD host controller version 4.00 or later ones, there're two modes of implementation - Version 3.00 compatible mode or Version 4 mode. This patch introduced an interface to enable v4 mode. Signed-off-by: Chunyan Zhang --- drivers/mmc/host/sdhci.c | 28 ++++++++++++++++++++++++++++ drivers/mmc/host/sdhci.h | 5 +++++ 2 files changed, 33 insertions(+) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 1c828e0..cab5350 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -123,6 +123,30 @@ EXPORT_SYMBOL_GPL(sdhci_dumpregs); * * \*****************************************************************************/ +static void sdhci_do_enable_v4_mode(struct sdhci_host *host) +{ + u16 ctrl2; + + ctrl2 = sdhci_readb(host, SDHCI_HOST_CONTROL2); + if (ctrl2 & SDHCI_CTRL_V4_MODE) + return; + + ctrl2 |= SDHCI_CTRL_V4_MODE; + sdhci_writeb(host, ctrl2, SDHCI_HOST_CONTROL); +} + +/* + * Vendor's Host Controller which supports v4 mode can call + * this function to enable v4 mode before calling + * __sdhci_add_host(). + */ +void sdhci_enable_v4_mode(struct sdhci_host *host) +{ + host->v4_mode = true; + sdhci_do_enable_v4_mode(host); +} +EXPORT_SYMBOL_GPL(sdhci_enable_v4_mode); + static inline bool sdhci_data_line_cmd(struct mmc_command *cmd) { return cmd->data || cmd->flags & MMC_RSP_BUSY; @@ -224,6 +248,10 @@ static void sdhci_do_reset(struct sdhci_host *host, u8 mask) /* Resetting the controller clears many */ host->preset_enabled = false; + + if (host->v4_mode) + sdhci_do_enable_v4_mode(host); + } } diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h index 23966f8..519d939 100644 --- a/drivers/mmc/host/sdhci.h +++ b/drivers/mmc/host/sdhci.h @@ -184,6 +184,7 @@ #define SDHCI_CTRL_DRV_TYPE_D 0x0030 #define SDHCI_CTRL_EXEC_TUNING 0x0040 #define SDHCI_CTRL_TUNED_CLK 0x0080 +#define SDHCI_CTRL_V4_MODE 0x1000 #define SDHCI_CTRL_PRESET_VAL_ENABLE 0x8000 #define SDHCI_CAPABILITIES 0x40 @@ -565,6 +566,9 @@ struct sdhci_host { u64 data_timeout; + /* Host Version 4 Enable */ + bool v4_mode; + unsigned long private[0] ____cacheline_aligned; }; @@ -747,5 +751,6 @@ bool sdhci_cqe_irq(struct sdhci_host *host, u32 intmask, int *cmd_error, int *data_error); void sdhci_dumpregs(struct sdhci_host *host); +void sdhci_enable_v4_mode(struct sdhci_host *host); #endif /* __SDHCI_HW_H */ -- 2.7.4