Messages in this thread | | | Date | Mon, 2 Sep 2013 16:42:00 +0530 | From | Vinod Koul <> | Subject | Re: [PATCH v4 3/3] dma: Add Freescale eDMA engine driver support |
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On Mon, Sep 02, 2013 at 07:32:53AM +0000, Lu Jingchang-B35083 wrote: > > > > > > > + chan->private = fn_param; > > > > > > why do you need to use chan->private? > > > > > [Lu Jingchang] > > > > > The private used here is to store the slot_id information, which > > must > > > > be used > > > > > by the DMAMUX in alloc_chan_resources function. Thanks. > > > > Why dont you pass this in struct dma_slave_config memeber slave_id > > for > > > > this. > > > [Lu Jingchang-b35083] > > > I will drop this private and setup the slave_id directly in the filter > > function. > > why in filter? before calling prepare function you can set the slave > > config > How about change the filter_fn to follow: > static bool fsl_edma_filter_fn(struct dma_chan *chan, void *fn_param) > { > struct fsl_edma_filter_param *fparam = fn_param; > struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan); > unsigned char val; > > if (fsl_chan->edmamux->mux_id != fparam->mux_id) > return false; > > val = EDMAMUX_CHCFG_ENBL | EDMAMUX_CHCFG_SOURCE(fparam->slot_id); > fsl_edmamux_config_chan(fsl_chan, val); > return true; > } > In fact the slot_id isn't need elsewhere, and if the filter return true, > This channel should be to this request. So no need to save the slave id, Right? something like
static bool fsl_edma_filter_fn(struct dma_chan *chan, void *fn_param) { struct fsl_edma_filter_param *fparam = fn_param; struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
if (fsl_chan->edmamux->mux_id != fparam->mux_id) return false; return true; }
in thedriver which calls this:
before prep:
config->slave_id = val;
dma_set_slave_config(chan, slave);
~Vinod
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