[PATCH v2 1/5] mmc: host: sdhci-s3c: Add broken-voltage DT property for broken voltage quirk

Jaehoon Chung jh80.chung at samsung.com
Wed Sep 19 07:02:37 EDT 2012


Hi,

On 09/19/2012 07:47 PM, Chris Ball wrote:
> Hi,
> 
> On Wed, Sep 19 2012, Tomasz Figa wrote:
>> We could just check if the regulator provides the capability to change the 
>> voltage.
>>
>> I don't see any direct way of querying the regulator for provided 
>> capabilities (correct me if I'm just blind), but calling 
>> regulator_count_voltages() on the regulator and checking if the returned 
>> value is 1 should be enough to assume that the regulator is fixed.
> 
> Sounds good, I agree.  Are you able to test that the obvious patch below
> works on your fixed-regulator board?
> 
> Jaehoon and Adrian, can you think of any reason why we shouldn't replace
> MMC_CAP2_BROKEN_VOLTAGE with the regulator_count_voltages() call below?
> Thanks.
I think this is better than using MMC_CAP2_BROKEN_VOLTAGE.
I tested with this..and working fine.

Best Regards,
Jaehoon Chung
> 
> 
> diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> index 044cd01..a3cc740 100644
> --- a/drivers/mmc/core/core.c
> +++ b/drivers/mmc/core/core.c
> @@ -1132,7 +1132,7 @@ int mmc_regulator_set_ocr(struct mmc_host *mmc,
>  		 */
>  		voltage = regulator_get_voltage(supply);
>  
> -		if (mmc->caps2 & MMC_CAP2_BROKEN_VOLTAGE)
> +		if (regulator_count_voltages(supply) == 1)
>  			min_uV = max_uV = voltage;
>  
>  		if (voltage < 0)
> 




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