Re: [PATCH] pwm: sl28cpld: fix getting driver data in pwm callbacks

[Michael Walle <michael@walle.cc>]

Am 2020-11-24 22:24, schrieb Uwe Kleine-König:
> Currently .get_state() and .apply() use dev_get_drvdata() on the struct
> device related to the pwm chip. This only works after .probe() called
> platform_set_drvdata() which in this driver happens only after
> pwmchip_add() and so comes possibly too late.
> 
> Instead of setting the driver data earlier use the traditional
> container_of approach as this way the driver data is conceptually and
> computational nearer.
> 
> Fixes: 9db33d221efc ("pwm: Add support for sl28cpld PWM controller")
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> ---
> Hello,
> 
> in v4 of the driver Michael still used container_of and then changed to
> use dev_get_drvdata() as Lee suggested. I didn't notice this 
> suggestion,
> otherwise I would have expressed my variance about this already 
> earlier.
> 
> I noticed this problem because Michael contacted me via irc and showed
> me the resulting oops, so I think applying this before 5.10 would be
> good. It's not entirely clear to me why .get_state() is called that
> early in his case, but the theory is clear: The callbacks can be called
> as soon as pwmchip_add() is called.
> 
> Best regards
> Uwe

Ping. Would be nice if this makes it into v5.10.

-michael