On Thu, Sep 15, 2011 at 07:48:36PM +0200, Guennadi Liakhovetski wrote: > On Thu, 15 Sep 2011, Sakari Ailus wrote: > > > javier Martin wrote: > > > Hi, > > > > Hi Javier, > > > > > we are planning to add support to H.264/MPEG4 encoder inside the > > > i.MX27 to v4l2. It is mainly a hardware module that has the following > > > features: > > > > > > - It needs two input buffers (current frame and previous frame). > > > - It produces a third buffer as output, containing the encoded frame, > > > and generates an IRQ when that happens. > > > - Previous three buffers need contiguous physical memory addresses and > > > probably some alignment requirements. > > > > CMA (contiguous memory allocator). This isn't in mainline yet, so so'll > > need to wait a little bit. > > > > > - It needs an external firmware to be loaded in another contiguous > > > memory buffer. > > > > This needs to be loaded using request_firmware(). > > > > > I would like to know what is your opinion on this, what v4l2 framework > > > should we use to deal with it, etc... I guess Multi Format Codec 5.1 > > > driver for s5pv210 and exynos4 SoC is the most similar piece of HW > > > I've found so far but it has not yet entered mainline [1] > > > > It sounds to me like that this device should be supported using the V4L2 > > interface. > > > > > Note that mx2_camera driver is still using soc-camera framework and > > > soc-camera doesn't seem to be ready for integration with pad level API > > > [2]. For that reason we think we could develop this VPU driver > > > separately. > > > > > > [1] http://www.spinics.net/lists/linux-media/msg35040.html > > > [2] http://www.open-technology.de/index.php?/categories/2-SoC-camera > > > > As Guennadi noted, the Media controller framework should be used to > > expose the control of more complex devices to user space than SoC camera > > can support. > > Hm, did I say that? Even more, as I write, I'm testing an soc-camera > extension to use the MC / pad-level API, implementing what I've proposed > here > > http://article.gmane.org/gmane.linux.drivers.video-input-infrastructure/38083 > > > However, it sounds like to me that the video produced by the camera has > > to be written to the system memory before it is processed by the > > H.264/MPEG4 encoder. For this reason, I don't see there would be a need > > to connect the camera driver to the encoder in kernel. Or am I wrong in > > thinking that these two are separate devices? > > Now, that's much more like what I've said here: > > http://article.gmane.org/gmane.linux.drivers.video-input-infrastructure/37826 Thanks for the corrections; they're indeed right I must have read your reply to Javier carelessly. :p -- Sakari Ailus e-mail: sakari.ailus@xxxxxx jabber/XMPP/Gmail: sailus@xxxxxxxxxxxxxx -- 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
