Re: mmc_test.ko usage

[Sheetal <sheetal.tigadoli@gmail.com>]

On Monday 12 October 2015 12:11 PM, Muni Sekhar wrote:
> On Mon, Oct 12, 2015 at 11:40 AM, Sheetal <sheetal.tigadoli@gmail.com> wrote:
>> On Monday 12 October 2015 11:25 AM, Muni Sekhar wrote:
>>> Hi ,
>>>
>>>
>>> I tried to use the MMC host test driver (mmc_test.ko) for testing SD
>>> Host controller hardware. When I load the driver I noticed that
>>> mmc_test_probe() not getting called.
>>>
>>> Could anyone specify the exact usage of mmc_test.ko?
>>>
>> Hello Muni Sekhar,
>>
>> I think the following might help you in using MMC_TEST.KO Module
>>
>> 0. insmod mmc_test.ko
>> 1. unbind the mmc block driver
>> echo mmc0:b368 > /sys/bus/mmc/drivers/mmcblk/unbind
>> 2. bind the mmc_test driver
>> echo mmc0:b368 > /sys/bus/mmc/drivers/mmc_test/bind
>> 3. mount the debugfs if you don't mount for debugfs
>> mount -t debugfs none /sys/kernel/debug
>> 4. After mount, you can see the "/sys/kernel/debug/mmc0/mmc0:b368/test"
>> 5. echo "test number" > /sys/kernel/debug/mmc0/mmc0\:b368/test
>> you can see the "test number" using the "cat
>> /sys/kernel/debug/mmc0/mmc0\:b368/testlist"
>>
>> The above has been copied straigtly from thelink
>> <http://forum.kernelnewbies.org/read.php?12,1991,116405#msg-116405>
>>
>
>
> Hello Sheetal,
>
>
>
> Thanks for the quick reply. I followed the steps but nmcblk unbind
> fails “bash: echo: write error: No such device”. Any idea about this
> failure?
>
>
>
> # echo mmc0:b368 > /sys/bus/mmc/drivers/mmcblk/unbind
>
> bash: echo: write error: No such device
>
>
>
>
> # ls -al /sys/bus/mmc/drivers/mmcblk
>
> total 0
>
> drwxr-xr-x 2 root root    0 Oct 12 11:49 .
>
> drwxr-xr-x 4 root root    0 Oct 12 11:49 ..
>
> --w------- 1 root root 4096 Oct 12 11:52 bind
>
> --w------- 1 root root 4096 Oct 12 11:49 uevent
>
> --w------- 1 root root 4096 Oct 12 11:52 unbind
>
>
>
> --
> Thanks,
> Sekhar
Hello Muni Sekhar,

You have to find the device node that has been created, In the example 
it was "mmc0:b368"
and appropriately modify the echo statement and every other statement 
where it is referenced

Thanks & Regards