[PATCH 16/40] mmc: tegra: Disable card clock during pad calibration
From: Aapo Vienamo <hidden>
Date: 2018-08-01 16:33:34
Also in:
linux-mmc, linux-tegra, lkml
Subsystem:
multimedia card (mmc), secure digital (sd) and sdio subsystem, secure digital host controller interface (sdhci) driver, the rest · Maintainers:
Ulf Hansson, Adrian Hunter, Linus Torvalds
Disable the card clock during automatic pad drive strength calibration and re-enable it afterwards. Signed-off-by: Aapo Vienamo <redacted> --- 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 9e22fec..c2b388b 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) } } +static bool tegra_sdhci_configure_card_clk(struct sdhci_host *host, bool enable) +{ + bool orig_enabled; + u32 reg; + + reg = sdhci_readw(host, SDHCI_CLOCK_CONTROL); + orig_enabled = !!(reg & SDHCI_CLOCK_CARD_EN); + + if (orig_enabled == enable) + return orig_enabled; + + if (enable) + reg |= SDHCI_CLOCK_CARD_EN; + else + reg &= ~SDHCI_CLOCK_CARD_EN; + + sdhci_writew(host, reg, SDHCI_CLOCK_CONTROL); + + return orig_enabled; +} + 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);
@@ -278,6 +302,8 @@ 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