<!-- Some styling for better description lists --><style type='text/css'>dt { font-weight: bold;float: left;display:inline;margin-right: 1em} dd { display:block; margin-left: 2em}</style>

   montjoie: I convert an old code (zoran) which use virt_to_bus() but I am not sure it is the best way
   ezequielg: <u>montjoie</u>: hello
   <br> how goes?
   <br> let me grep real quick.
   montjoie: goes fine, I finaly made zoran converted to vb2, but sometime crash and ever black/green result
   pinchartl: <u>montjoie</u>: which vb2 allocator do you use ?
   <br> dma-contig or dma-sg ?
   montjoie: vmalloc ?
   pinchartl: with dma-contig, you get the DMA address with vb2_dma_contig_plane_dma_addr() (the DMA address is what you need to program in the device, and can be different from the physical address if there's an IOMMU in your system)
   <br> vmalloc, really ?
   <br> there's no physical address for vmalloc buffers
   <br> they're not contiguous in memory, and generally not suitable for DMA
   montjoie: okay so it explain the random crash
   pinchartl: :-)
   <br> remind me, does the zoran hardware support scatter-gather, or does it require contiguous buffers ?
   montjoie: continuous according to my understanding
   <br> https://github.com/montjoie/linux/tree/zoran-5.3.16
   pinchartl: then you need to use dma-contig, and vb2_dma_contig_plane_dma_addr()
   montjoie: in case you want to saw some horror
   pinchartl: if the hardware supported scatter-gather, dma-sg and vb2_dma_sg_plane_desc()
   montjoie: okay thanks I saw some use of vb2_dma_contig_plane_dma_addr and I was trying to use it
   pinchartl: I've had enough horror for the weekend, thanks :-)
   montjoie: virt_to_bus() seems really bad
   pinchartl: virt_to_bus() is bad indeed
   <br> briefly looking at the code, dma-contig is what you want indeed
   <br> that's the first v4l driver I worked on... I'd be happy seeing it coming back to life :-)
   montjoie: <u>pinchartl</u>: with vb2 it will be much cleaner
   <br> all fh stuff will disappear
   ezequielg: <u>pinchartl</u>: you replied faster than i get my laptop.
   <br> haven't we removed zoran from upstream?
   <br> is it used nowadays?
   pinchartl: it has been removed, yes
   <br> I assume it's used by montjoie at least :-)
   ezequielg: ah, just found the "bringing back" mail.
   <br> nowadays, vb2 makes pci capture drivers _really_ _really_ easy.
   <br> <u>montjoie</u>: good luck with that, shout us if you need help
   -: ezequielg goes back to sunday sun
   montjoie: <u>ezequielg</u>: yes removed and I need it (and learning v4l for fun)
   ezequielg: <u>montjoie</u>: well, have fun :)
   oni: https://github.com/alievk/avatarify
   <br> Not sure if this has been posted. Did what I was thinking of doing with v4l2loopback
   montjoie: converting to dma-cont was eassy, but well crashing the second try...
   ***: awalls has left
   ezequielg: <u>montjoie</u>: have you considered just starting a vb2 driver from scratch?
   <br> might sound crazy, but after the initial learning phase, it might end up being more fun and less painful.