On Mon, Nov 05, 2018 at 04:22:54PM +0200, Andy Shevchenko wrote: > On Sun, Nov 04, 2018 at 06:01:39PM +0100, Christian Lamparter wrote: > > + struct dw_dma *dw = to_dw_dma(dwc->chan.device); > > + size_t chanidx = (size_t)(dwc - dw->chan); > > We have mask field, so, index is a first set bit out of mask, __ffs(mask). > > unsigned int protctl = dw->pdata->protctl[__ffs(mask)]; dwc->mask, of course. Also, it's possible to use (though better to check) dwc->chan.chan_id, though I dunno if it's reliable. -- With Best Regards, Andy Shevchenko
