Re: [PATCH 10/10] drivers: misc: use module_platform_driver_probe()

[Fabio Porcedda <fabio.porcedda@gmail.com>]

On Thu, Mar 14, 2013 at 3:06 PM, Sascha Hauer <s.hauer@pengutronix.de> wrote:
> On Thu, Mar 14, 2013 at 01:58:05PM +0000, Arnd Bergmann wrote:
>> On Thursday 14 March 2013, Fabio Porcedda wrote:
>> > This patch converts the drivers to use the
>> > module_platform_driver_probe() macro which makes the code smaller and
>> > a bit simpler.
>> >
>> > Signed-off-by: Fabio Porcedda <fabio.porcedda@gmail.com>
>> > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> > Cc: Arnd Bergmann <arnd@arndb.de>
>> > ---
>> >  drivers/misc/atmel_pwm.c  | 12 +-----------
>> >  drivers/misc/ep93xx_pwm.c | 13 +------------
>> >  2 files changed, 2 insertions(+), 23 deletions(-)
>>
>> The patch itself seems fine, but there are two issues around it:
>>
>> * The PWM drivers should really get moved to drivers/pwm and converted to the new
>>   PWM subsystem. I don't know if Hartley or Hans-Christian have plans to do
>>   that already.
>>
>> * Regarding the use of module_platform_driver_probe, I'm a little worried about
>>   the interactions with deferred probing. I don't think there are any regressions,
>>   but we should probably make people aware that one cannot return -EPROBE_DEFER
>>   from a platform_driver_probe function.

The use of module_platform_driver_probe() doesn't change anything about that,
it's exactly the same thing as using "return platform_driver_probe()".
I'm right or I'm missing something? Maybe are you just speaking about
the misuse of "platform_driver_probe"?

Best regards
Fabio Porcedda

>
> I'm worried about this aswell. I think platform_driver_probe shouldn't
> be used anymore. Even if a driver does not explicitly make use of
> -EPROBE_DEFER, it leaks in very quickly if a driver for example uses a
> regulator and just returns the error value from regulator_get.

> Sascha
>
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