On 28/02/19 9:35 AM, Yinbo Zhu wrote:
> From: Yangbo Lu <yangbo.lu@xxxxxxx>
>
> For some controllers, in Present State Register, Data Line
> Active bit is not reliable for commands (such as CMD6, CMD7,
> CMD12, CMD28, CMD29, or CMD38) with busy signal. DLA affects
> Command with Data Inhibit bit. Therefore, software driver
> may not know the busy status in DLA/CDIHB.
>
> Futunately MMC core driver has already polled card status
> with CMD13 after sending any command with busy signal. So
> we can just ignore CDIHB never released issue for such
> controllers. This patch is to add a quirk to handle this.
>
> Signed-off-by: Yangbo Lu <yangbo.lu@xxxxxxx>
> Signed-off-by: Yinbo Zhu <yinbo.zhu@xxxxxxx>
> ---
> Change in v2:
> Instead masking the bit in esdhc_readl_fixup()
>
> drivers/mmc/host/sdhci-of-esdhc.c | 13 +++++++++++++
> drivers/mmc/host/sdhci.h | 2 +-
> 2 files changed, 14 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-of-esdhc.c b/drivers/mmc/host/sdhci-of-esdhc.c
> index 7e0eae8..8c78ad8 100644
> --- a/drivers/mmc/host/sdhci-of-esdhc.c
> +++ b/drivers/mmc/host/sdhci-of-esdhc.c
> @@ -147,6 +147,19 @@ static u32 esdhc_readl_fixup(struct sdhci_host *host,
> return ret;
> }
>
> + /*
> + * Some controllers have unreliable Data Line Active
> + * bit for commands with busy signal. This affects
> + * Command Inhibit (data) bit. Just ignore it since
> + * MMC core driver has already polled card status
> + * with CMD13 after any command with busy siganl.
> + */
> + if ((spec_reg == SDHCI_PRESENT_STATE) &&
> + (host->quirks2 & SDHCI_QUIRK2_IGNORE_DATA_INHIBIT)) {
Can you do this without adding a new quirk in sdhci.h? Perhaps add a flag
to sdhci_esdhc.
> + ret = value & ~SDHCI_DATA_INHIBIT;
> + return ret;
> + }
> +
> ret = value;
> return ret;
> }
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> index 01002cb..65075b8 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -485,7 +485,7 @@ struct sdhci_host {
> * block count.
> */
> #define SDHCI_QUIRK2_USE_32BIT_BLK_CNT (1<<18)
> -
> +#define SDHCI_QUIRK2_IGNORE_DATA_INHIBIT (1<<19)
> int irq; /* Device IRQ */
> void __iomem *ioaddr; /* Mapped address */
> char *bounce_buffer; /* For packing SDMA reads/writes */
>
