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authorBing Zhao2013-11-26 15:39:20 -0800
committerChris Ball2014-01-17 22:55:01 -0500
commite5624054c1726a16c13a89c08b2792aba3df06eb (patch)
tree2f54f5abf6337ed1571e6dd872a2e32164382f70 /drivers
parent2b35bd83467df6f8284b9148d6f768148c3a5e5f (diff)
mmc: sdio: add a quirk for broken SDIO_CCCR_INTx polling
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. Signed-off-by: Bing Zhao <bzhao@marvell.com> Reviewed-by: Paul Stewart <pstew@chromium.org> Reviewed-by: Doug Anderson <dianders@chromium.org> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Chris Ball <chris@printf.net>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/mmc/core/quirks.c8
-rw-r--r--drivers/mmc/core/sdio_irq.c11
2 files changed, 19 insertions, 0 deletions
diff --git a/drivers/mmc/core/quirks.c b/drivers/mmc/core/quirks.c
index 06ee1aeaacec..6c36fccaa1ec 100644
--- a/drivers/mmc/core/quirks.c
+++ b/drivers/mmc/core/quirks.c
@@ -13,6 +13,7 @@
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/mmc/card.h>
+#include <linux/mmc/sdio_ids.h>
#ifndef SDIO_VENDOR_ID_TI
#define SDIO_VENDOR_ID_TI 0x0097
@@ -30,6 +31,10 @@
#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 +63,9 @@ 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
};
diff --git a/drivers/mmc/core/sdio_irq.c b/drivers/mmc/core/sdio_irq.c
index 3d8ceb4084de..aaa90460ed23 100644
--- a/drivers/mmc/core/sdio_irq.c
+++ b/drivers/mmc/core/sdio_irq.c
@@ -53,6 +53,17 @@ static int process_sdio_pending_irqs(struct mmc_host *host)
return ret;
}
+ if (pending && mmc_card_broken_irq_polling(card) &&
+ !(host->caps & MMC_CAP_SDIO_IRQ)) {
+ 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 avoid this.
+ */
+ mmc_io_rw_direct(card, 0, 0, 0xff, 0, &dummy);
+ }
+
count = 0;
for (i = 1; i <= 7; i++) {
if (pending & (1 << i)) {