[U-Boot] [PATCH 1/4] mmc: Retry the switch command

[Jaehoon Chung]

On 11/14/2016 03:50 AM, Hans de Goede wrote:
> Hi,
> 
> On 04-11-16 16:18, Maxime Ripard wrote:
>> Some eMMC will fail at the first switch, but would succeed in a subsequent
>> one.
>>
>> Make sure we try several times to cover those cases. The number of retries
>> (and the behaviour) is currently what is being used in Linux.
>>
>> Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>
> 
> LGTM:
> 
> Reviewed-by: Hans de Goede <hdegoede at redhat.com>
> 
> Pantelis or Tom, can you pick this up please ?

Applied on u-boot-mmc. Thanks!

Best Regards,
Jaehoon Chung

> 
> Regards,
> 
> Hans
> 
> 
>> ---
>>  drivers/mmc/mmc.c | 15 +++++++++++----
>>  1 file changed, 11 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
>> index 4380c7c195a6..d6b7e4f510c9 100644
>> --- a/drivers/mmc/mmc.c
>> +++ b/drivers/mmc/mmc.c
>> @@ -494,6 +494,7 @@ int mmc_switch(struct mmc *mmc, u8 set, u8 index, u8 value)
>>  {
>>      struct mmc_cmd cmd;
>>      int timeout = 1000;
>> +    int retries = 3;
>>      int ret;
>>
>>      cmd.cmdidx = MMC_CMD_SWITCH;
>> @@ -502,11 +503,17 @@ int mmc_switch(struct mmc *mmc, u8 set, u8 index, u8 value)
>>                   (index << 16) |
>>                   (value << 8);
>>
>> -    ret = mmc_send_cmd(mmc, &cmd, NULL);
>> +    while (retries > 0) {
>> +        ret = mmc_send_cmd(mmc, &cmd, NULL);
>>
>> -    /* Waiting for the ready status */
>> -    if (!ret)
>> -        ret = mmc_send_status(mmc, timeout);
>> +        /* Waiting for the ready status */
>> +        if (!ret) {
>> +            ret = mmc_send_status(mmc, timeout);
>> +            return ret;
>> +        }
>> +
>> +        retries--;
>> +    }
>>
>>      return ret;
>>
>>
> 
> 
>