Re: [PATCH v6 2/4] dmaengine: tegra: Add tegra gpcdma driver

[Jon Hunter]

On 22/09/2021 15:46, Akhil R wrote:
> > On 17/09/2021 15:11, Akhil R wrote:
> > > +static int tegra_dma_slave_config(struct dma_chan *dc,
> > > +				  struct dma_slave_config *sconfig) {
> > > +	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
> > > +
> > > +	if (tdc->dma_desc) {
> > > +		dev_err(tdc2dev(tdc), "Configuration not allowed\n");
> > > +		return -EBUSY;
> > > +	}
> > > +
> > > +	memcpy(&tdc->dma_sconfig, sconfig, sizeof(*sconfig));
> > > +	if (tdc->slave_id == -1)
> > > +		tdc->slave_id = sconfig->slave_id;
> > > +
> > > +	tdc->config_init = true;
> > > +	return 0;
> > > +}
> >
> > So you have a function to reserve a slave ID, but you don't check here if it is
> > already reserved.
> slave-id is reserved considering the direction as well.
> 'direction' is available only during prep_slave_sg function, I guess.

Sorry I don't understand what you mean by that.

Jon

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