Re: [PATCH 3/3] drivers core: allow id match override when manually binding driver

[Michal Suchanek]

On 26 June 2016 at 20:28, Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> On Thu, Jun 23, 2016 at 05:41:20PM -0000, Michal Suchanek wrote:
>> This allows binding spidev on any slave device by hand using sysfs
>> without adding superfluous compatibles or any other needless
>> complication.
>>
>> Note that any slave driver that requires configuration will fail to
>> probe anyway. Only a driver that binds to anything can be bound
>> successfully.
>>
>> Signed-off-by: Michal Suchanek <hramrach@xxxxxxxxx>
>> ---
>>  drivers/base/Kconfig.debug | 14 +++++++++
>>  drivers/base/bus.c         | 72 +++++++++++++++++++++++++++++++++++++++++++++-
>>  lib/Kconfig.debug          |  2 ++
>>  3 files changed, 87 insertions(+), 1 deletion(-)
>>  create mode 100644 drivers/base/Kconfig.debug
>>
>> diff --git a/drivers/base/Kconfig.debug b/drivers/base/Kconfig.debug
>> new file mode 100644
>> index 0000000..e21d3cc
>> --- /dev/null
>> +++ b/drivers/base/Kconfig.debug
>> @@ -0,0 +1,14 @@
>> +menuconfig DRIVER_MATCH_OVERRIDE
>> +     bool "Allow manual driver binding to override id match (DANGEROUS)"
>> +     default n
>> +     help
>> +       When binding a driver manually bypass the check of driver id table
>> +       against device id in driver core. This can be useful for development
>> +       or on buses that don't provide reliable device identification.
>
> Ick, no no no.  Why would you ever want to let this happen?  If you
> really want to override the check, just write things to the 'bind' file
> in sysfs, that will skip the driver id check entirely, right?

Well, it does not. Hence this patch which enables skipping the check.
It's the whole point of it.

Thanks

Michal