[PATCH] mmc: sdhci-of-at91: wait for calibration done before proceed

[Claudiu Beznea]

Datasheet specifies that at the end of calibration the SDMMC_CALCR_EN
bit will be cleared. No commands should be send before calibration is
done.

Fixes: dbdea70f71d67 ("mmc: sdhci-of-at91: fix CALCR register being rewritten")
Fixes: 727d836a375ad ("mmc: sdhci-of-at91: add DT property to enable calibration on full reset")
Signed-off-by: Claudiu Beznea <claudiu.beznea at microchip.com>
---
 drivers/mmc/host/sdhci-of-at91.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/mmc/host/sdhci-of-at91.c b/drivers/mmc/host/sdhci-of-at91.c
index 5564d7b23e7c..2b28711e039d 100644
--- a/drivers/mmc/host/sdhci-of-at91.c
+++ b/drivers/mmc/host/sdhci-of-at91.c
@@ -114,6 +114,8 @@ static void sdhci_at91_reset(struct sdhci_host *host, u8 mask)
 {
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
+	unsigned long timeout = jiffies + msecs_to_jiffies(20);
+	unsigned int tmp;
 
 	sdhci_reset(host, mask);
 
@@ -126,6 +128,14 @@ static void sdhci_at91_reset(struct sdhci_host *host, u8 mask)
 
 		sdhci_writel(host, calcr | SDMMC_CALCR_ALWYSON | SDMMC_CALCR_EN,
 			     SDMMC_CALCR);
+
+		do {
+			tmp = sdhci_readl(host, SDMMC_CALCR);
+		} while (time_before(jiffies, timeout) &&
+			 (tmp & SDMMC_CALCR_EN));
+
+		if (tmp & SDMMC_CALCR_EN)
+			dev_err(mmc_dev(host->mmc), "Failed to calibrate\n");
 	}
 }
 
-- 
2.25.1