Re: [PATCH v4 1/2] mmc: sdhci: export sdhci_execute_tuning()
From: Adrian Hunter
Date: Thu Dec 08 2016 - 06:58:11 EST
On 08/12/16 13:49, Adrian Hunter wrote:
> On 05/12/16 04:10, Masahiro Yamada wrote:
>> Some SDHCI-compat controllers support not only SD, but also eMMC,
>> but they use different commands for tuning: CMD19 for SD, CMD21 for
>> eMMC.
>>
>> Due to the difference of the underlying mechanism, some controllers
>> (at least, the Cadence IP is the case) provide their own registers
>> for the eMMC tuning.
>>
>> This commit will be useful when we want to override .execute_tuning
>> callback (for eMMC HS200 tuning), but still let it fall back to
>> sdhci_execute_tuning() for SD timing.
>>
>> Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
>
> Adrian Hunter <adrian.hunter@xxxxxxxxx>
I mean:
Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
>
>> ---
>>
>> I want to use this in the next commit.
>> The Cadence IP supports eMMC as well as SD.
>>
>> I want to re-use the sdhci_execute_tuning() for SD timing.
>>
>> On the other hand, Cadence provides its own way for eMMC HS200 tuning;
>> I need to touch some registers that are specific to Cadence's design.
>>
>>
>> Changes in v4:
>> - export sdhci_execute_tuning() instead of using
>> execute_execute_tuning()
>>
>> Changes in v3: None
>> Changes in v2: None
>>
>> drivers/mmc/host/sdhci.c | 3 ++-
>> drivers/mmc/host/sdhci.h | 1 +
>> 2 files changed, 3 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
>> index 42ef3eb..0c03a89 100644
>> --- a/drivers/mmc/host/sdhci.c
>> +++ b/drivers/mmc/host/sdhci.c
>> @@ -1948,7 +1948,7 @@ static int sdhci_prepare_hs400_tuning(struct mmc_host *mmc, struct mmc_ios *ios)
>> return 0;
>> }
>>
>> -static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode)
>> +int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode)
>> {
>> struct sdhci_host *host = mmc_priv(mmc);
>> u16 ctrl;
>> @@ -2141,6 +2141,7 @@ static int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode)
>> spin_unlock_irqrestore(&host->lock, flags);
>> return err;
>> }
>> +EXPORT_SYMBOL_GPL(sdhci_execute_tuning);
>>
>> static int sdhci_select_drive_strength(struct mmc_card *card,
>> unsigned int max_dtr, int host_drv,
>> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
>> index 9c35776..786eee9 100644
>> --- a/drivers/mmc/host/sdhci.h
>> +++ b/drivers/mmc/host/sdhci.h
>> @@ -689,6 +689,7 @@ void sdhci_set_power_noreg(struct sdhci_host *host, unsigned char mode,
>> void sdhci_set_bus_width(struct sdhci_host *host, int width);
>> void sdhci_reset(struct sdhci_host *host, u8 mask);
>> void sdhci_set_uhs_signaling(struct sdhci_host *host, unsigned timing);
>> +int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode);
>>
>> #ifdef CONFIG_PM
>> extern int sdhci_suspend_host(struct sdhci_host *host);
>>
>
>