Intel BXT/APL use a card detect GPIO however the host controller
will not enable bus power unless it's card detect also reflects
the presence of a card. Unfortunately those 2 things race which
can result in commands not starting, after which the controller
does nothing and there is a 10 second wait for the driver's
10-second timer to timeout.
That is fixed by having the driver look also at the present state
register to determine if the card is present. Consequently, provide
a 'get_cd' mmc host operation for BXT/APL that does that.
Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v4.4+
---
drivers/mmc/host/sdhci-acpi.c | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)
diff --git a/drivers/mmc/host/sdhci-acpi.c b/drivers/mmc/host/sdhci-acpi.c
index 3d27f2de0054..195ff0853dc8 100644
--- a/drivers/mmc/host/sdhci-acpi.c
+++ b/drivers/mmc/host/sdhci-acpi.c
@@ -146,6 +146,33 @@ static const struct sdhci_acpi_chip sdhci_acpi_chip_int = {
.ops = &sdhci_acpi_ops_int,
};
+static int bxt_get_cd(struct mmc_host *mmc)
+{
+ int gpio_cd = mmc_gpio_get_cd(mmc);
+ struct sdhci_host *host = mmc_priv(mmc);
+ unsigned long flags;
+ int ret = 0;
+
+ if (!gpio_cd)
+ return 0;
+
+ pm_runtime_get_sync(mmc->parent);
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ if (host->flags & SDHCI_DEVICE_DEAD)
+ goto out;
+
+ ret = !!(sdhci_readl(host, SDHCI_PRESENT_STATE) & SDHCI_CARD_PRESENT);
+out:
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ pm_runtime_mark_last_busy(mmc->parent);
+ pm_runtime_put_autosuspend(mmc->parent);
+
+ return ret;
+}
+
static int sdhci_acpi_emmc_probe_slot(struct platform_device *pdev,
const char *hid, const char *uid)
{
@@ -196,6 +223,9 @@ static int sdhci_acpi_sd_probe_slot(struct platform_device *pdev,
/* Platform specific code during sd probe slot goes here */
+ if (hid && !strcmp(hid, "80865ACA"))
+ host->mmc_host_ops.get_cd = bxt_get_cd;
+
return 0;
}
--
1.9.1
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