This patch adds SDHCI_QUIRK_BROKEN_CARD_DETECTION quirk. When specified,
sdhci driver will set MMC_CAP_NEEDS_POLL MMC host capability, and won't
enable card insert/remove interrupts.
This is needed for hosts with unreliable card detection, such as FSL
eSDHC. The original eSDHC driver was tring to "debounce" card-detection
IRQs by reading present state and disabling particular interrupts. But
with this debouncing scheme I noticed that sometimes we miss card
insertion/removal events.
Signed-off-by: Anton Vorontsov <avoront...@ru.mvista.com>
---
drivers/mmc/host/sdhci.c | 17 ++++++++++++++---
drivers/mmc/host/sdhci.h | 2 ++
2 files changed, 16 insertions(+), 3 deletions(-)
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 2728e90..782fb58 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -167,6 +167,9 @@ static void sdhci_set_card_detection(struct sdhci_host
*host, bool enable)
{
u32 irqs = SDHCI_INT_CARD_REMOVE | SDHCI_INT_CARD_INSERT;
+ if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION)
+ return;
+
if (enable)
sdhci_unmask_irqs(host, irqs);
else
@@ -1110,13 +1113,18 @@ static void sdhci_request(struct mmc_host *mmc, struct
mmc_request *mrq)
host->mrq = mrq;
+ if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION)
+ goto send;
+
if (!(sdhci_readl(host, SDHCI_PRESENT_STATE) & SDHCI_CARD_PRESENT)
|| (host->flags & SDHCI_DEVICE_DEAD)) {
host->mrq->cmd->error = -ENOMEDIUM;
tasklet_schedule(&host->finish_tasklet);
- } else
- sdhci_send_command(host, mrq->cmd);
-
+ goto out;
+ }
+send:
+ sdhci_send_command(host, mrq->cmd);
+out:
mmiowb();
spin_unlock_irqrestore(&host->lock, flags);
}
@@ -1742,6 +1750,9 @@ int sdhci_add_host(struct sdhci_host *host)
mmc->f_max = host->max_clk;
mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
+ if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION)
+ mmc->caps |= MMC_CAP_NEEDS_POLL;
+
if ((caps & SDHCI_CAN_DO_HISPD) ||
(host->quirks & SDHCI_QUIRK_FORCE_HIGHSPEED))
mmc->caps |= MMC_CAP_SD_HIGHSPEED;
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 45c8309..b10920d 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -217,6 +217,8 @@ struct sdhci_host {
#define SDHCI_QUIRK_FORCE_HIGHSPEED (1<<14)
/* Controller does not provide transfer-complete interrupt when not busy */
#define SDHCI_QUIRK_NO_BUSY_IRQ (1<<15)
+/* Controller has unreliable card detection */
+#define SDHCI_QUIRK_BROKEN_CARD_DETECTION (1<<16)
int irq; /* Device IRQ */
void __iomem * ioaddr; /* Mapped address */
--
1.5.6.5
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