Re: [RFC PATCH V3 11/21] mmc: sdhci: UHS-II support, export host operations to core

[Adrian Hunter <adrian.hunter@intel.com>]

On 10/07/20 2:10 pm, Ben Chuang wrote:
> From: AKASHI Takahiro <takahiro.akashi@linaro.org>
> 
> Export sdhci-specific UHS-II operations to core.
> 
> Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> ---
>  drivers/mmc/host/sdhci.c | 70 ++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 70 insertions(+)
> 
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index c2f6923d296c..aaf41954511a 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -2977,6 +2977,70 @@ static void sdhci_card_event(struct mmc_host *mmc)
>  	spin_unlock_irqrestore(&host->lock, flags);
>  }
>  
> +#if IS_ENABLED(CONFIG_MMC_SDHCI_UHS2)
> +static int sdhci_uhs2_detect_init(struct mmc_host *mmc)
> +{
> +	struct sdhci_host *host = mmc_priv(mmc);
> +	int ret;
> +
> +	if (sdhci_uhs2_ops.do_detect_init)
> +		ret = sdhci_uhs2_ops.do_detect_init(host);
> +	else
> +		return 0;
> +
> +	return ret;
> +}
> +
> +static int sdhci_uhs2_set_reg(struct mmc_host *mmc, enum uhs2_act act)
> +{
> +	struct sdhci_host *host = mmc_priv(mmc);
> +	int ret;
> +
> +	if (sdhci_uhs2_ops.do_set_reg)
> +		ret = sdhci_uhs2_ops.do_set_reg(host, act);
> +	else
> +		ret = 0;
> +
> +	return ret;
> +}
> +
> +static void sdhci_uhs2_disable_clk(struct mmc_host *mmc)
> +{
> +	struct sdhci_host *host = mmc_priv(mmc);
> +	u16 clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> +
> +	clk &= ~SDHCI_CLOCK_CARD_EN;
> +	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> +}
> +
> +static void sdhci_uhs2_enable_clk(struct mmc_host *mmc)
> +{
> +	struct sdhci_host *host = mmc_priv(mmc);
> +	u16 clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> +	ktime_t timeout;
> +
> +	clk |= SDHCI_CLOCK_CARD_EN;
> +	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> +
> +	/* Wait max 20 ms */
> +	timeout = ktime_add_ms(ktime_get(), 20);
> +	while (1) {
> +		bool timedout = ktime_after(ktime_get(), timeout);
> +
> +		clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> +		if (clk & SDHCI_CLOCK_INT_STABLE)
> +			break;
> +		if (timedout) {
> +			pr_err("%s: Internal clock never stabilised.\n",
> +			       mmc_hostname(host->mmc));
> +			sdhci_dumpregs(host);
> +			return;
> +		}
> +		udelay(10);
> +	}
> +}
> +#endif /* CONFIG_MMC_SDHCI_UHS2 */

Please put all uhs2 functions in sdhci-uhs2.c and call them through sdhci_ops.

> +
>  static const struct mmc_host_ops sdhci_ops = {
>  	.request	= sdhci_request,
>  	.post_req	= sdhci_post_req,
> @@ -2992,6 +3056,12 @@ static const struct mmc_host_ops sdhci_ops = {
>  	.execute_tuning			= sdhci_execute_tuning,
>  	.card_event			= sdhci_card_event,
>  	.card_busy	= sdhci_card_busy,
> +#if IS_ENABLED(CONFIG_MMC_SDHCI_UHS2)
> +	.uhs2_detect_init	= sdhci_uhs2_detect_init,
> +	.uhs2_set_reg		= sdhci_uhs2_set_reg,
> +	.uhs2_disable_clk	= sdhci_uhs2_disable_clk,
> +	.uhs2_enable_clk	= sdhci_uhs2_enable_clk,
> +#endif /* CONFIG_MMC_SDHCI_UHS2 */
>  };
>  
>  /*****************************************************************************\
>