[PATCH 2/5] dmaengine: Add STM32 DMAMUX driver

Vinod Koul vinod.koul at intel.com
Sun Apr 30 23:03:53 PDT 2017


On Wed, Apr 26, 2017 at 09:17:37AM +0000, Pierre Yves MORDRET wrote:
> >> +
> >> +	ret = of_property_read_u32(node, "dma-channels",
> >> +				   &dmamux->dmamux_channels);
> >
> > can we have property_xxx calls alone, that way driver is not strictly
> > dependent on of
> 
> Can you please explain what you are asking for ? Not sure to understand 
> correctly.

Use device_property_read_u32() which is a generic property API.


> >> +static int __init stm32_dmamux_init(void)
> >> +{
> >> +	return platform_driver_register(&stm32_dmamux_driver);
> >> +}
> >> +arch_initcall(stm32_dmamux_init);
> >
> > why not module init, wouldnt defer probe solve the dependencies
> >
> 
> The reason behind many devices (device_initcall level) rely on DMAs. If 
> init is deferred DMAMUX driver will be probed twice if dependents rely 
> on it. This sounds not a good call. This explains arch_initcall level.

Why not deferred probe was introduced to help with dependencies...

-- 
~Vinod



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