On Mon, Nov 05, 2018 at 05:06:20PM +0100, Christian Lamparter wrote: > On Monday, November 5, 2018 3:27:41 PM CET Andy Shevchenko wrote: > > 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. > Ok, will do. I'll sent a v2 later this week. > > > Also, it's possible to use (though better to check) dwc->chan.chan_id, > > though I dunno if it's reliable. > dwc->chan.chan_id is subjected to the chan_allocation setting. > So, if it's set to CHAN_ALLOCATION_DESCENDING the dt prop array values > for the protctl would need to be reversed as well in order to match the > other per-channel settings (for example multiblock). > So, let's not do that since this gets very confusing. Yes, that's what I suspected. So, __ffs(dwc->mask) seems feasible approach. -- With Best Regards, Andy Shevchenko
