Re: [PATCH] mmc: dw_mmc: add busmode selection support

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On 24 July 2012 18:37, Jae hoon Chung <jh80.chung@xxxxxxxxx> wrote:
> Hi Girish,
>
> Right, it be mentioned about the open-drain mode in synopsys spec.
> But if didn't work on other board, there is some problem.
> We can consider the location of set_busmode() .
may i know the board on which you are testing. i will try to use the
same and simulate the problem
>
> Best Regards,
> Jaehoon Chung
>
> 2012/7/24 Girish K S <girish.shivananjappa@xxxxxxxxxx>:
>> On 24 July 2012 17:06, Girish K S <girish.shivananjappa@xxxxxxxxxx> wrote:
>>> On 24 July 2012 16:39, Jaehoon Chung <jh80.chung@xxxxxxxxxxx> wrote:
>>>> Hi Girish,
>>>>
>>>> Well..just tested on my board.
>>>> this patch didn't work.(eMMC card didn't initialize)
>>>> meaning of ios->bus_mode and synosys's bus_mode is same?
>> Yes it is same. synopsys spec says this is specific to MMC
>> initialization. when the card core sets this mode during
>> initialization. the host has to set this bit
>>>> How did you test this patch?
>>> Tested it on exynos5 board using dt patches of thomas (with some
>>> modification to his patch)
>>>>
>>>> Best Regards,
>>>> Jaehoon Chung
>>>>
>>>> On 07/23/2012 08:16 PM, Girish K S wrote:
>>>>> Synopsis Designware host controller has suppport for open
>>>>> drain mode selection. During the mmc card initialization the
>>>>> host controller can select the open-drain bit to allow the device
>>>>> initialization in the open-drain mode. Once the device enters
>>>>> the standby mode this bit can be reset to enter push-pull mode.
>>>>>
>>>>> Signed-off-by: Girish K S <girish.shivananjappa@xxxxxxxxxx>
>>>>> ---
>>>>>  drivers/mmc/host/dw_mmc.c |   14 ++++++++++++++
>>>>>  drivers/mmc/host/dw_mmc.h |    1 +
>>>>>  2 files changed, 15 insertions(+), 0 deletions(-)
>>>>>
>>>>> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
>>>>> index 72dc3cd..da11e5a 100644
>>>>> --- a/drivers/mmc/host/dw_mmc.c
>>>>> +++ b/drivers/mmc/host/dw_mmc.c
>>>>> @@ -773,6 +773,18 @@ static void dw_mci_request(struct mmc_host *mmc, struct mmc_request *mrq)
>>>>>       spin_unlock_bh(&host->lock);
>>>>>  }
>>>>>
>>>>> +static void dw_mci_set_busmode(struct dw_mci_slot *slot)
>>>>> +{
>>>>> +     struct mmc_ios *ios = &slot->mmc->ios;
>>>>> +     u32 reg;
>>>>> +
>>>>> +     reg = mci_readl(slot->host, CTRL);
>>>>> +     if (ios->bus_mode == MMC_BUSMODE_OPENDRAIN)
>>>>> +             mci_writel(slot->host, CTRL, reg | SDMMC_CTRL_ENABLE_OD);
>>>>> +     else
>>>>> +             mci_writel(slot->host, CTRL, reg & ~SDMMC_CTRL_ENABLE_OD);
>>>>> +}
>>>>> +
>>>>>  static void dw_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
>>>>>  {
>>>>>       struct dw_mci_slot *slot = mmc_priv(mmc);
>>>>> @@ -818,6 +830,8 @@ static void dw_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
>>>>>       default:
>>>>>               break;
>>>>>       }
>>>>> +
>>>>> +     dw_mci_set_busmode(slot);
>>>>>  }
>>>>>
>>>>>  static int dw_mci_get_ro(struct mmc_host *mmc)
>>>>> diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h
>>>>> index 15c27e1..1a53fb2 100644
>>>>> --- a/drivers/mmc/host/dw_mmc.h
>>>>> +++ b/drivers/mmc/host/dw_mmc.h
>>>>> @@ -67,6 +67,7 @@
>>>>>
>>>>>  /* Control register defines */
>>>>>  #define SDMMC_CTRL_USE_IDMAC         BIT(25)
>>>>> +#define SDMMC_CTRL_ENABLE_OD         BIT(24)
>>>>>  #define SDMMC_CTRL_CEATA_INT_EN              BIT(11)
>>>>>  #define SDMMC_CTRL_SEND_AS_CCSD              BIT(10)
>>>>>  #define SDMMC_CTRL_SEND_CCSD         BIT(9)
>>>>>
>>>>
>>>>
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