On 23/07/18 13:08, Chunyan Zhang wrote:
> 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 <zhang.chunyan@xxxxxxxxxx>
> ---
> 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);
Instead of sdhci_do_reset() I would rather add this to sdhci_init() and
__sdhci_read_caps()
> +
> }
> }
>
> 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;
Let's put this with the other bools i.e. after bool irq_wake_enabled;
> +
> 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 */
>
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
