On Fri, 2012-12-14 at 08:33 +0900, Jaehoon Chung wrote: > Hi Dinh, > > According to DesignWare Spec, we need to check which bus-mode use. > You can refer to "https://patchwork.kernel.org/patch/1379521/";. > I know that hold_reg didn't use always, although hold_reg is set. Hi Jaehoon, Thanks for the info. So then my question is what is the correct way to add support for use_hold_reg? Our implementation of the IP is using the use_hold_reg in its default state. The driver taken as is did not work. Should we be adding a similar file dw_mmc-exynos.c to add this? Thanks, Dinh > > Best Regards, > Jaehoon Chung > > On 12/14/2012 05:03 AM, dinguyen@xxxxxxxxxx wrote: > > From: Dinh Nguyen <dinguyen@xxxxxxxxxx> > > > > Add code to read value of the use_hold_reg in the cmd register so that > > the cmdflags can be correct. > > > > Signed-off-by: Dinh Nguyen <dinguyen@xxxxxxxxxx> > > --- > > drivers/mmc/host/dw_mmc.c | 6 ++++++ > > drivers/mmc/host/dw_mmc.h | 1 + > > include/linux/mmc/dw_mmc.h | 3 +++ > > 3 files changed, 10 insertions(+) > > > > diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c > > index 323c502..490490b 100644 > > --- a/drivers/mmc/host/dw_mmc.c > > +++ b/drivers/mmc/host/dw_mmc.c > > @@ -265,6 +265,9 @@ static u32 dw_mci_prepare_command(struct mmc_host *mmc, struct mmc_command *cmd) > > if (drv_data && drv_data->prepare_command) > > drv_data->prepare_command(slot->host, &cmdr); > > > > + if (slot->host->use_hold_reg) > > + cmdr |= SDMMC_CMD_USE_HOLD_REG; > > + > > return cmdr; > > } > > > > @@ -2183,6 +2186,9 @@ int dw_mci_probe(struct dw_mci *host) > > host->data_shift = 2; > > } > > > > + /* Get the USE_HOLD_REG */ > > + host->use_hold_reg = mci_readl(host, CMD) & SDMMC_CMD_USE_HOLD_REG; > > + > > /* Reset all blocks */ > > if (!mci_wait_reset(host->dev, host)) > > return -ENODEV; > > diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h > > index 53b8fd9..6172900 100644 > > --- a/drivers/mmc/host/dw_mmc.h > > +++ b/drivers/mmc/host/dw_mmc.h > > @@ -111,6 +111,7 @@ > > #define SDMMC_INT_ERROR 0xbfc2 > > /* Command register defines */ > > #define SDMMC_CMD_START BIT(31) > > +#define SDMMC_CMD_USE_HOLD_REG BIT(29) > > #define SDMMC_CMD_CCS_EXP BIT(23) > > #define SDMMC_CMD_CEATA_RD BIT(22) > > #define SDMMC_CMD_UPD_CLK BIT(21) > > diff --git a/include/linux/mmc/dw_mmc.h b/include/linux/mmc/dw_mmc.h > > index 34be4f4..36cab8a 100644 > > --- a/include/linux/mmc/dw_mmc.h > > +++ b/include/linux/mmc/dw_mmc.h > > @@ -187,6 +187,9 @@ struct dw_mci { > > struct regulator *vmmc; /* Power regulator */ > > unsigned long irq_flags; /* IRQ flags */ > > int irq; > > + > > + /* Set to one for SDR12 and SDR25 */ > > + unsigned int use_hold_reg; > > }; > > > > /* DMA ops for Internal/External DMAC interface */ > > > > -- 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
