On 21 March 2016 at 08:44, Hans Verkuil <[email protected]> wrote: > Hi Ezequiel, > > On 03/02/2016 03:30 PM, Ezequiel Garcia wrote: >> This commit introduces the support for the Techwell TW686x video >> capture IC. This hardware supports a few DMA modes, including >> scatter-gather and frame (contiguous). >> >> This commit makes little use of the DMA engine and instead has >> a memcpy based implementation. DMA frame and scatter-gather modes >> support may be added in the future. >> >> Currently supported chips: >> - TW6864 (4 video channels), >> - TW6865 (4 video channels, not tested, second generation chip), >> - TW6868 (8 video channels but only 4 first channels using >> built-in video decoder are supported, not tested), >> - TW6869 (8 video channels, second generation chip). >> >> Cc: Krzysztof Hałasa <[email protected]> >> Signed-off-by: Ezequiel Garcia <[email protected]> > > I've tested this with my PCIe tw6869 card (arrived this week). > > Video is fine, but only the first audio input is available. I suspect you > have only one audio input? >
The driver exposes the eight audio channels as subdevices (ALSA substreams) of a single device. $ sudo arecord -l **** List of CAPTURE Hardware Devices **** [..] card 1: tw686x [tw686x], device 0: tw686x [tw686x PCM] Subdevices: 8/8 Subdevice #0: vch0 audio Subdevice #1: vch1 audio Subdevice #2: vch2 audio Subdevice #3: vch3 audio Subdevice #4: vch4 audio Subdevice #5: vch5 audio Subdevice #6: vch6 audio Subdevice #7: vch7 audio > Regarding the memcpy: if you have a patch for me that reverts back to a > non-memcpy > situation, then I can do duration tests for you. > Yes, that would be great. I've just pushed my staging branch: http://git.infradead.org/users/ezequielg/linux/shortlog/refs/heads/tw686x-upstream-for-v4.7 It introduces a dma_mode parameter which let's the user pick the DMA operation. It accepts these values: memcpy, contig, sg. Only "memcpy" and "contig" are working, while "sg" needs more work. Feel free to test it and let me know how it goes. Thanks, -- Ezequiel García, VanguardiaSur www.vanguardiasur.com.ar -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
