From 61dad40eb955c577ae6a2cefd351c05770d67794 Mon Sep 17 00:00:00 2001 From: Aapo Vienamo Date: Mon, 20 Aug 2018 12:23:33 +0300 Subject: [PATCH] mmc: tegra: Implement periodic pad calibration Rerun the pad calibration procedure before sdhci_request() if the 100 ms recalibration interval has been exceeded. Signed-off-by: Aapo Vienamo Acked-by: Adrian Hunter Acked-by: Thierry Reding Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci-tegra.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c index 88ffc7e..ea56628 100644 --- a/drivers/mmc/host/sdhci-tegra.c +++ b/drivers/mmc/host/sdhci-tegra.c @@ -30,6 +30,7 @@ #include #include #include +#include #include "sdhci-pltfm.h" @@ -122,6 +123,7 @@ struct sdhci_tegra { struct pinctrl_state *pinctrl_state_1v8; struct sdhci_tegra_autocal_offsets autocal_offsets; + ktime_t last_calib; u32 default_tap; u32 default_trim; @@ -555,6 +557,22 @@ static void tegra_sdhci_parse_pad_autocal_dt(struct sdhci_host *host) autocal->pull_down_hs400 = autocal->pull_down_1v8; } +static void tegra_sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq) +{ + struct sdhci_host *host = mmc_priv(mmc); + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host); + ktime_t since_calib = ktime_sub(ktime_get(), tegra_host->last_calib); + + /* 100 ms calibration interval is specified in the TRM */ + if (ktime_to_ms(since_calib) > 100) { + tegra_sdhci_pad_autocalib(host); + tegra_host->last_calib = ktime_get(); + } + + sdhci_request(mmc, mrq); +} + static void tegra_sdhci_parse_tap_and_trim(struct sdhci_host *host) { struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); @@ -1045,6 +1063,10 @@ static int sdhci_tegra_probe(struct platform_device *pdev) sdhci_tegra_start_signal_voltage_switch; } + /* Hook to periodically rerun pad calibration */ + if (soc_data->nvquirks & NVQUIRK_HAS_PADCALIB) + host->mmc_host_ops.request = tegra_sdhci_request; + host->mmc_host_ops.hs400_enhanced_strobe = tegra_sdhci_hs400_enhanced_strobe; -- 2.7.4