On Thu, Mar 14, 2013 at 3:06 PM, Sascha Hauer [off-list ref] wrote:

On Thu, Mar 14, 2013 at 01:58:05PM +0000, Arnd Bergmann wrote:

quoted

On Thursday 14 March 2013, Fabio Porcedda wrote:

quoted

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 <redacted>
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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