On 26 November 2013 00:53, Bing Zhao <bzhao@xxxxxxxxxxx> wrote:
> 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);
> +}
I would suggest you follow how the other quirks has been implemented,
thus I don't think you need a separate function just for invoking an
extra mmc_io_rw_direct, do directly in sdio_irq.c instead.
> 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) &&
Suggest you add an mmc_card_broken_irq_poll(), in card.h. Like the
other quirks are handled.
> + !(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
>
Otherwise, looks fine!
Kind regards
Ulf Hansson
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