Re: [PATCH] mmc: host: omap_hsmmc: add a verbose print to enable CONFIG_REGULATOR_PBIAS

From: Kishon Vijay Abraham I
Date: Thu Jan 14 2016 - 07:40:09 EST


Hi,

On Thursday 14 January 2016 05:37 PM, Sebastian Reichel wrote:
> Hi,
>
> On Thu, Jan 14, 2016 at 02:45:20PM +0530, Kishon Vijay Abraham I wrote:
>> Since v4.3+, CONFIG_REGULATOR_PBIAS should be enabled (for platforms that
>> have PBIAS regulator) in order for MMC1 to work.
>>
>> Add a more verbose print to help enable CONFIG_REGULATOR_PBIAS for users
>> using a olddefconfig or a custom .config.
>>
>> Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
>> ---
>> drivers/mmc/host/omap_hsmmc.c | 5 ++++-
>> 1 file changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
>> index 7fb0753..7086bd6 100644
>> --- a/drivers/mmc/host/omap_hsmmc.c
>> +++ b/drivers/mmc/host/omap_hsmmc.c
>> @@ -503,8 +503,11 @@ static int omap_hsmmc_reg_get(struct omap_hsmmc_host *host)
>> host->pbias = devm_regulator_get_optional(host->dev, "pbias");
>> if (IS_ERR(host->pbias)) {
>> ret = PTR_ERR(host->pbias);
>> - if ((ret != -ENODEV) && host->dev->of_node)
>> + if ((ret != -ENODEV) && host->dev->of_node) {
>> + dev_err(host->dev,
>> + "SD card detect fail? enable CONFIG_REGULATOR_PBIAS\n");
>> return ret;
>> + }
>> dev_dbg(host->dev, "unable to get pbias regulator %ld\n",
>> PTR_ERR(host->pbias));
>> host->pbias = NULL;
>
>
> Is there a good reason against adding "depends on REGULATOR_PBIAS"
> to MMC_OMAP_HS? I guess it's required for most systems and the regulator
> driver is just 250 loc. I am aware, that this will disable the
> hsmmc driver for 'make oldconfig', but I guess that will be noticed
> in a similar way your warning is noticed.

hmm.. only MMC1 requires PBIAS so I'm not sure if it's okay to add depends on
REGULATOR_PBIAS for the HSMMC driver as such. And as you said it'll also
disable the hsmmc driver if oldconfig is used. But do we get a warning?

Thanks
Kishon