Commit e5624054 authored by Bing Zhao's avatar Bing Zhao Committed by Chris Ball
Browse files

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: default avatarBing Zhao <bzhao@marvell.com>
Reviewed-by: default avatarPaul Stewart <pstew@chromium.org>
Reviewed-by: default avatarDoug Anderson <dianders@chromium.org>
Acked-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: default avatarChris Ball <chris@printf.net>
parent 2b35bd83

drivers/mmc/core/quirks.c

+8 −0
Original line number Diff line number Diff line
@@ -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

};

drivers/mmc/core/sdio_irq.c

+11 −0
Original line number Diff line number Diff line
@@ -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)) {

include/linux/mmc/card.h

+7 −1
Original line number Diff line number Diff line
@@ -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 */
@@ -505,6 +506,11 @@ static inline int mmc_card_long_read_time(const struct mmc_card *c) 
	return c->quirks & MMC_QUIRK_LONG_READ_TIME;

}



static inline int mmc_card_broken_irq_polling(const struct mmc_card *c)

{

	return c->quirks & MMC_QUIRK_BROKEN_IRQ_POLLING;

}



#define mmc_card_name(c)	((c)->cid.prod_name)

#define mmc_card_id(c)		(dev_name(&(c)->dev))

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