In some Soc'S that integrate Designware mmc host controllers, the HCON register is broken. The hardware configuration is not updated. One specific usecase is the IDMAC. In Exysons5 SoC there exist a internal DMA, but the HCON register's DMA_INTERFACE field is not set to indicate its existance. This quirk can be used in such case to force the existance broken HCON field. Signed-off-by: Girish K S <girish.shivananjappa@xxxxxxxxxx> --- drivers/mmc/host/dw_mmc-pltfm.c | 5 +++++ drivers/mmc/host/dw_mmc.c | 11 ++++++++++- drivers/mmc/host/dw_mmc.h | 1 + include/linux/mmc/host.h | 1 + 4 files changed, 17 insertions(+), 1 deletions(-) diff --git a/drivers/mmc/host/dw_mmc-pltfm.c b/drivers/mmc/host/dw_mmc-pltfm.c index 900f412..24ea485 100644 --- a/drivers/mmc/host/dw_mmc-pltfm.c +++ b/drivers/mmc/host/dw_mmc-pltfm.c @@ -35,9 +35,14 @@ static unsigned long exynos5250_dwmmc_caps[4] = { MMC_CAP_CMD23, }; +static unsigned long exynos5250_dwmmc_caps2[1] = { + MMC_CAP2_CONFIG_BROKEN, +}; + static struct dw_mci_drv_data exynos5250_drv_data = { .ctrl_type = DW_MCI_TYPE_EXYNOS5250, .caps = exynos5250_dwmmc_caps, + .caps2 = exynos5250_dwmmc_caps2, }; static const struct of_device_id dw_mci_pltfm_match[] = { diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c index 1a59a92..030224c 100644 --- a/drivers/mmc/host/dw_mmc.c +++ b/drivers/mmc/host/dw_mmc.c @@ -431,7 +431,13 @@ static int dw_mci_idmac_init(struct dw_mci *host) /* Check if Hardware Configuration Register has support for DMA */ dma_support = (mci_readl(host, HCON) >> 16) & 0x3; - if (!dma_support || dma_support > 2) { + /* + * In Some of the Soc's the HCON Register is broken. Even though the + * Soc's has a internal DMA the HCON register's DMA field doesnt + * show it. So additional quirk is added for such Soc's + */ + if ((!dma_support || dma_support > 2) && + !((u32)host->drv_data->caps2 & MMC_CAP2_CONFIG_BROKEN)) { dev_err(&host->dev, "Host Controller does not support IDMA Tx.\n"); host->dma_ops = NULL; @@ -1957,6 +1963,9 @@ static int __init dw_mci_init_slot(struct dw_mci *host, unsigned int id) if (host->pdata->caps2) mmc->caps2 = host->pdata->caps2; + if (host->drv_data->caps2) + mmc->caps2 |= host->drv_data->caps2[ctrl_id]; + if (host->pdata->get_bus_wd) { if (host->pdata->get_bus_wd(slot->id) >= 4) mmc->caps |= MMC_CAP_4_BIT_DATA; diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h index 6c17282..8c4810a 100644 --- a/drivers/mmc/host/dw_mmc.h +++ b/drivers/mmc/host/dw_mmc.h @@ -203,6 +203,7 @@ extern int dw_mci_resume(struct dw_mci *host); struct dw_mci_drv_data { unsigned long ctrl_type; unsigned long *caps; + unsigned long *caps2; }; #endif /* _DW_MMC_H_ */ diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 65c64ee..ab5c7f9 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -261,6 +261,7 @@ struct mmc_host { #define MMC_CAP2_HC_ERASE_SZ (1 << 9) /* High-capacity erase size */ #define MMC_CAP2_CD_ACTIVE_HIGH (1 << 10) /* Card-detect signal active high */ #define MMC_CAP2_RO_ACTIVE_HIGH (1 << 11) /* Write-protect signal active high */ +#define MMC_CAP2_CONFIG_BROKEN (1 << 12) /* Broken Config Register */ mmc_pm_flag_t pm_caps; /* supported pm features */ unsigned int power_notify_type; -- 1.7.4.1 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html