Hi Girish, On 07/16/2012 05:45 PM, Girish K S wrote: > 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)) { Just caps2? if use the device tree, need to get ctrl_id? It didn't work.. > 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; > -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html