From 887bda8f21ee78b14678853ee6ecdd6569196054 Mon Sep 17 00:00:00 2001 From: Aapo Vienamo Date: Thu, 30 Aug 2018 18:06:16 +0300 Subject: [PATCH] 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: Aapo Vienamo Acked-by: Thierry Reding Acked-by: Adrian Hunter Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci-tegra.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c index e63cd6b..ec07a3c 100644 --- a/drivers/mmc/host/sdhci-tegra.c +++ b/drivers/mmc/host/sdhci-tegra.c @@ -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"); } -- 2.7.4