Hi Peter, Thank you for the patch. On Friday 04 Nov 2016 09:58:02 Peter Ujfalusi wrote: > When requesting the DMA channel it was mandatory that we do not have DMA > resource nor valid DMA channel via DT. In this case the > dma_request_slave_channel_compat() would fall back and request any channel > with SW trigger. > > The same can be achieved with the dma_request_chan_by_mask() without the > misleading use of the DMAengine API - implying that the omap3isp does > need to have DMA resource or valid dma binding in DT. > > Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx> > CC: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > CC: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxx> Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> and added to my tree. > --- > Hi, > > Changes sicne v1: > - use dma_request_chan_by_mask() to request the channel as for the histogram > data reading we do not have hw syncronisation. Add comment about this also > to clarify the reason. > > Regards, > Peter > > drivers/media/platform/omap3isp/isphist.c | 28 +++++++++++++++------------- > 1 file changed, 15 insertions(+), 13 deletions(-) > > diff --git a/drivers/media/platform/omap3isp/isphist.c > b/drivers/media/platform/omap3isp/isphist.c index > 7138b043a4aa..a4ed5d140d48 100644 > --- a/drivers/media/platform/omap3isp/isphist.c > +++ b/drivers/media/platform/omap3isp/isphist.c > @@ -18,7 +18,6 @@ > #include <linux/delay.h> > #include <linux/device.h> > #include <linux/dmaengine.h> > -#include <linux/omap-dmaengine.h> > #include <linux/slab.h> > #include <linux/uaccess.h> > > @@ -486,27 +485,30 @@ int omap3isp_hist_init(struct isp_device *isp) > hist->isp = isp; > > if (HIST_CONFIG_DMA) { > - struct platform_device *pdev = to_platform_device(isp->dev); > - struct resource *res; > - unsigned int sig = 0; > dma_cap_mask_t mask; > > + /* > + * We need slave capable channel without DMA request line for > + * reading out the data. > + * For this we can use dma_request_chan_by_mask() as we are > + * happy with any channel as long as it is capable of slave > + * configuration. > + */ > dma_cap_zero(mask); > dma_cap_set(DMA_SLAVE, mask); > + hist->dma_ch = dma_request_chan_by_mask(&mask); > + if (IS_ERR(hist->dma_ch)) { > + ret = PTR_ERR(hist->dma_ch); > + if (ret == -EPROBE_DEFER) > + return ret; > > - res = platform_get_resource_byname(pdev, IORESOURCE_DMA, > - "hist"); > - if (res) > - sig = res->start; > - > - hist->dma_ch = dma_request_slave_channel_compat(mask, > - omap_dma_filter_fn, &sig, isp->dev, "hist"); > - if (!hist->dma_ch) > + hist->dma_ch = NULL; > dev_warn(isp->dev, > "hist: DMA channel request failed, using PIO\n"); > - else > + } else { > dev_dbg(isp->dev, "hist: using DMA channel %s\n", > dma_chan_name(hist->dma_ch)); > + } > } > > hist->ops = &hist_ops; -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html