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Subject[PATCH] MMC: Add 400ms to CAFE SD controller resume path

The CAFE SD controller takes a long time to completely resume
and w/o this patch, we do not redetect an existing card but
instead detect it as a new one. Even with MMC_UNSAFE_RESUME
enabled, this leads to the partition table on the device being
wiped out.

See http://dev.laptop.org/ticket/6532 for gory details.

Signed-off-by: Deepak Saxena <dsaxena@laptop.org>

---

diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c
index 65be279..9941bb0 100644
--- a/drivers/mmc/host/sdhci-pci.c
+++ b/drivers/mmc/host/sdhci-pci.c
@@ -105,10 +105,26 @@ static const struct sdhci_pci_fixes sdhci_ene_714 = {
SDHCI_QUIRK_BROKEN_DMA,
};

+
+/*
+ * This 400ms timeout is needed to ensure that the chip has proper time to
+ * wake up an redetect an already inserted card. Without this, we end up
+ * corrupting the partition table on the device.
+ *
+ * See http://dev.laptop.org/ticket/6532 for lots of ugly details.
+ */
+static int cafe_resume(struct sdhci_pci_chip *chip)
+{
+ msleep(400);
+
+ return 0;
+}
+
static const struct sdhci_pci_fixes sdhci_cafe = {
.quirks = SDHCI_QUIRK_NO_SIMULT_VDD_AND_POWER |
SDHCI_QUIRK_NO_BUSY_IRQ |
SDHCI_QUIRK_BROKEN_TIMEOUT_VAL,
+ .resume = cafe_resume,
};

static int jmicron_pmos(struct sdhci_pci_chip *chip, int on)

--
In the end, they will not say, "those were dark times," they will ask
"why were their poets silent?" - Bertold Brecht



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