Hello Krzysztof, Thanks a lot for your feedback. On 03/27/2015 03:38 PM, Krzysztof Kozlowski wrote: > 2015-03-27 15:21 GMT+01:00 Javier Martinez Canillas > <javier.martinez@xxxxxxxxxxxxxxx>: >> Commit ae43b3289186 ("ARM: 8202/1: dmaengine: pl330: Add runtime Power >> Management support v12") added pm support for the pl330 dma driver but >> it makes the clock for the Exynos5420 MDMA0 DMA controller to be gated >> during suspend and this clock needs to remain enabled in order to make >> the system resume from a system suspend state. >> >> To make sure that the clock is enabled during suspend, enable it prior >> to entering a suspend state and disable it once the system has resumed. >> >> Thanks to Abhilash Kesavan for figuring out that this was the issue. >> >> Fixes: ae43b32 ("ARM: 8202/1: dmaengine: pl330: Add runtime Power Management support v12") >> Signed-off-by: Javier Martinez Canillas <javier.martinez@xxxxxxxxxxxxxxx> > > Hmmm... isn't a real problem elsewhere - like some clock hierarchy is > wrong or incomplete? This rather looks like workaround for the > problem. > That's a very good question, that's why I sent it as an RFC. I didn't find anything relevant in the manual but I could certainly be missing something. >> >> @@ -516,6 +528,9 @@ static void exynos5420_pm_resume(void) >> { >> unsigned long tmp; >> >> + if (!IS_ERR_OR_NULL(clk)) >> + clk_disable_unprepare(clk); >> + > > Missing clk_put() > Yes, Sylwester already pointed it out. Sorry for missing that. > Best regards, > Krzysztof > Best regards, Javier -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html