On 9/23/21 7:52 AM, Jaehoon Chung wrote:
> Hi Chritstian,
>
> On 9/16/21 2:59 PM, Christian Löhle wrote:
>> Only wait for DRTO on reads, otherwise the driver hangs.
>>
>> The driver prevents sending CMD12 on response errors like CRCs.
>> According to the comment this is because some cards have problems
>> with this during the UHS tuning sequence.
>> Unfortunately this workaround currently also applies for any command
>> with data.
>> On reads this will set the drto timer which then triggers after a while.
>> On writes this will not set any timer and the tasklet will not be
>> scheduled again.
>> I cannot attest for the UHS workarounds need, but even if so, it should
>> at most apply to reads.
>> I have observed many hangs when CMD25 response contained a CRC error.
>> This patch fixes this without touching the actual UHS tuning workaround.
>
> Sorry for reply too late. I'm checking your patch on my target.
> I will share the result.
>
> Best Regards,
> Jaehoon Chung
>
>>
>> Signed-off-by: Christian Loehle <cloehle@xxxxxxxxxxxxxx>
Reviewed-by: Jaehoon Chung <jh80.chung@xxxxxxxxxxx>
Best Regards,
Jaehoon Chung
>> ---
>> drivers/mmc/host/dw_mmc.c | 3 ++-
>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
>> index 6578cc64ae9e..22cf13dc799b 100644
>> --- a/drivers/mmc/host/dw_mmc.c
>> +++ b/drivers/mmc/host/dw_mmc.c
>> @@ -2081,7 +2081,8 @@ static void dw_mci_tasklet_func(struct tasklet_struct *t)
>> * delayed. Allowing the transfer to take place
>> * avoids races and keeps things simple.
>> */
>> - if (err != -ETIMEDOUT) {
>> + if (err != -ETIMEDOUT &&
>> + host->dir_status == DW_MCI_RECV_STATUS) {
>> state = STATE_SENDING_DATA;
>> continue;
>> }
>>
>
>
