Re: [PATCH 2/4 v4] i.MX31: Image Processing Unit DMA and IRQ drivers

On Tue, Dec 23, 2008 at 05:33:11PM +0100, Guennadi Liakhovetski wrote:

These all are just slightly different variations - with this one you'd 
have to scan dma channels in your dma irq handler, which I currently don't 
have to do.

quoted

That said I'm not sure whether we need a chained interrupt handler at all.
Looking at the remaining interrupts it seems that for example the
CSI_EOF (IPU_INT_STAT3 bit 5) interrupt is redundant to the corresponding
channels interrupt. In the camera driver you already realized that it's
the dma end event you're interested in, not the CSI_EOF event. Not sure
if that holds for the other interrupts though.

I think the version with a lookup table is optimal - it uses standard 
mechanisms for irq handling and doesn't waste RAM. The disadvantage - 
every addition will need driver modification...

But ok, this is taking way too long. Just tell me which way you'd like to 
have it and I'll do it.

Preferably a way which does not involve introducing 100+ unused
interrupts.

Sascha

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