Polling SDIO_CCCR_INTx could create a fake interrupt with Marvell
SD8797 card. Add a quirk to handle this case. The fixup here is
to issue a dummy CMD52 read to function 0 register 0xff, and this
dummy read must be right after SDIO_CCCR_INTx is read.
Patch has been verified on a dw_mmc controller (Samsung Chromebook)
with MMC_CAP_SDIO_IRQ disabled.
Reviewed-by: Paul Stewart <pstew@xxxxxxxxxxxx>
Reviewed-by: Doug Anderson <dianders@xxxxxxxxxxxx>
Signed-off-by: Bing Zhao <bzhao@xxxxxxxxxxx>
---
drivers/mmc/core/quirks.c | 21 +++++++++++++++++++++
drivers/mmc/core/sdio_irq.c | 5 +++++
include/linux/mmc/card.h | 4 +++-
3 files changed, 29 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/core/quirks.c b/drivers/mmc/core/quirks.c
index 06ee1ae..870bcc3 100644
--- a/drivers/mmc/core/quirks.c
+++ b/drivers/mmc/core/quirks.c
@@ -13,6 +13,9 @@
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/mmc/card.h>
+#include <linux/mmc/sdio_ids.h>
+
+#include "sdio_ops.h"
#ifndef SDIO_VENDOR_ID_TI
#define SDIO_VENDOR_ID_TI 0x0097
@@ -30,6 +33,10 @@
#define SDIO_DEVICE_ID_STE_CW1200 0x2280
#endif
+#ifndef SDIO_DEVICE_ID_MARVELL_8797_F0
+#define SDIO_DEVICE_ID_MARVELL_8797_F0 0x9128
+#endif
+
/*
* This hook just adds a quirk for all sdio devices
*/
@@ -58,6 +65,9 @@ static const struct mmc_fixup mmc_fixup_methods[] = {
SDIO_FIXUP(SDIO_VENDOR_ID_STE, SDIO_DEVICE_ID_STE_CW1200,
add_quirk, MMC_QUIRK_BROKEN_BYTE_MODE_512),
+ SDIO_FIXUP(SDIO_VENDOR_ID_MARVELL, SDIO_DEVICE_ID_MARVELL_8797_F0,
+ add_quirk, MMC_QUIRK_BROKEN_IRQ_POLLING),
+
END_FIXUP
};
@@ -89,3 +99,14 @@ void mmc_fixup_device(struct mmc_card *card, const struct mmc_fixup *table)
}
}
EXPORT_SYMBOL(mmc_fixup_device);
+
+void mmc_fixup_broken_irq_polling(struct mmc_card *card)
+{
+ unsigned char dummy;
+
+ /* A fake interrupt could be created when we poll SDIO_CCCR_INTx
+ * register with a Marvell SD8797 card. A dummy CMD52 read to
+ * function 0 register 0xff can aviod this.
+ */
+ mmc_io_rw_direct(card, 0, 0, 0xff, 0, &dummy);
+}
diff --git a/drivers/mmc/core/sdio_irq.c b/drivers/mmc/core/sdio_irq.c
index 3d8ceb4..afb00e1 100644
--- a/drivers/mmc/core/sdio_irq.c
+++ b/drivers/mmc/core/sdio_irq.c
@@ -47,6 +47,11 @@ static int process_sdio_pending_irqs(struct mmc_host *host)
}
ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_INTx, 0, &pending);
+
+ if (pending && (card->quirks & MMC_QUIRK_BROKEN_IRQ_POLLING) &&
+ !(host->caps & MMC_CAP_SDIO_IRQ))
+ mmc_fixup_broken_irq_polling(card);
+
if (ret) {
pr_debug("%s: error %d reading SDIO_CCCR_INTx\n",
mmc_card_id(card), ret);
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index 176fdf8..08a065b 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -271,9 +271,10 @@ struct mmc_card {
#define MMC_QUIRK_INAND_CMD38 (1<<6) /* iNAND devices have broken CMD38 */
#define MMC_QUIRK_BLK_NO_CMD23 (1<<7) /* Avoid CMD23 for regular multiblock */
#define MMC_QUIRK_BROKEN_BYTE_MODE_512 (1<<8) /* Avoid sending 512 bytes in */
+ /* byte mode */
#define MMC_QUIRK_LONG_READ_TIME (1<<9) /* Data read time > CSD says */
#define MMC_QUIRK_SEC_ERASE_TRIM_BROKEN (1<<10) /* Skip secure for erase/trim */
- /* byte mode */
+#define MMC_QUIRK_BROKEN_IRQ_POLLING (1<<11) /* Polling SDIO_CCCR_INTx could create a fake interrupt */
unsigned int erase_size; /* erase size in sectors */
unsigned int erase_shift; /* if erase unit is power 2 */
@@ -531,5 +532,6 @@ extern void mmc_unregister_driver(struct mmc_driver *);
extern void mmc_fixup_device(struct mmc_card *card,
const struct mmc_fixup *table);
+extern void mmc_fixup_broken_irq_polling(struct mmc_card *card);
#endif /* LINUX_MMC_CARD_H */
--
1.8.0
--
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