Commit 887bda8f authored by Aapo Vienamo's avatar Aapo Vienamo Committed by Ulf Hansson
Browse files

mmc: tegra: Disable card clock during pad calibration 



Disable the card clock during automatic pad drive strength calibration
and re-enable it afterwards.

Signed-off-by: default avatarAapo Vienamo <avienamo@nvidia.com>
Acked-by: default avatarThierry Reding <treding@nvidia.com>
Acked-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent 212b0cf1

drivers/mmc/host/sdhci-tegra.c

+26 −0
Original line number Diff line number Diff line
@@ -260,11 +260,35 @@ static void tegra_sdhci_configure_cal_pad(struct sdhci_host *host, bool enable) 
		usleep_range(1, 2);

}



static bool tegra_sdhci_configure_card_clk(struct sdhci_host *host, bool enable)

{

	bool status;

	u32 reg;



	reg = sdhci_readw(host, SDHCI_CLOCK_CONTROL);

	status = !!(reg & SDHCI_CLOCK_CARD_EN);



	if (status == enable)

		return status;



	if (enable)

		reg |= SDHCI_CLOCK_CARD_EN;

	else

		reg &= ~SDHCI_CLOCK_CARD_EN;



	sdhci_writew(host, reg, SDHCI_CLOCK_CONTROL);



	return status;

}



static void tegra_sdhci_pad_autocalib(struct sdhci_host *host)

{

	bool card_clk_enabled;

	u32 reg;

	int ret;



	card_clk_enabled = tegra_sdhci_configure_card_clk(host, false);



	tegra_sdhci_configure_cal_pad(host, true);



	reg = sdhci_readl(host, SDHCI_TEGRA_AUTO_CAL_CONFIG);
@@ -279,6 +303,8 @@ static void tegra_sdhci_pad_autocalib(struct sdhci_host *host) 


	tegra_sdhci_configure_cal_pad(host, false);



	tegra_sdhci_configure_card_clk(host, card_clk_enabled);



	if (ret)

		dev_err(mmc_dev(host->mmc), "Pad autocal timed out\n");

}

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