Re: [PATCH] tmio_mmc_pio: prevent endless loop in tmio_mmc_set_clock()

[Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>]

Hello.

On 06/26/2014 11:56 PM, Sergei Shtylyov wrote:

>> I've spent a couple of days with the driver just hanging due to me forgetting
>> to specify the external crystal frequency, so that clk_get_rate() returned 0
>> and thus the loop in tmio_mmc_set_clock() never ended. I don't think that's an
>> acceptable behavior, so I suggest that the minimum frequency is checked for 0
>> in tmio_mmc_host_probe().

>> Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>

>> ---
>> The patch is against Chris Ball's 'mmc.git' repo's 'master' branch.

>     I'm still not seeing this patch applied anywhere in this repo... what's
> the problem with it?

    Chris, Ulf, Ian, what's the issue with this patch? Do you want me to 
rework it?

>>   drivers/mmc/host/tmio_mmc_pio.c |    9 +++++++++
>>   1 file changed, 9 insertions(+)
>
>> Index: mmc/drivers/mmc/host/tmio_mmc_pio.c
>> ===================================================================
>> --- mmc.orig/drivers/mmc/host/tmio_mmc_pio.c
>> +++ mmc/drivers/mmc/host/tmio_mmc_pio.c
>> @@ -1044,6 +1044,15 @@ int tmio_mmc_host_probe(struct tmio_mmc_
>>       }
>>
>>       /*
>> +     * Check the sanity of mmc->f_min to prevent tmio_mmc_set_clock() from
>> +     * looping forever...
>> +     */
>> +    if (mmc->f_min == 0) {
>> +        ret = -EINVAL;
>> +        goto pm_disable;
>> +    }
>> +
>> +    /*
>>        * There are 4 different scenarios for the card detection:
>>        *  1) an external gpio irq handles the cd (best for power savings)
>>        *  2) internal sdhi irq handles the cd

WBR, Sergei