This is the third version of an initial set of patches showing the approach I'm taking in order to fulfill all the MC needs that was discussed on the 3 day MC summit in Helsinki. This version comes with the changes requested at the ML: - added unions at links for source/port0/entity and sink/port1/interface. That avoided adding macros to get the pad from the graph_obj on most places; - removed a wrong initialization for the reserse link at the pad create link function; - merged a fixup patch that was sent in separate by mistake on the previous series. ===== The goal of this patchset is: 1) to create a common struct that will be embedded on all internal structs that represents the comon data that will be used by all kinds of objects; 2) to have an unique object ID for each object in the graph. The object ID will be needed by the userspace API in the future, as discussed during the MC workshop; 3) to create objects to represent Kernel->userspace interfaces; 4) to extend the link support to allow linking interfaces to entities. On version 2, I removed the kref, as some people at the #v4l channel are not convinced about its need. So, let's postpone such discussion when we start introducing patches that will actually do dynamic object removal in runtime. As suggested, I'll be sending incremental patches and avoiding to do a large set of changes into one changeset series. That basically means that those patches aren't tested yet (except for compilation tests). Along this patch series, I'll be calling "object" as any "symbol" that belongs to a media graph, like processing entities, connectors, links, pads, interfaces. As said on the goals of this RFC, on version 2 of this patch series, we're coming with the new concept: interfaces. An interface is a graph object that does the interaction between Kernelspace <===> Userspace. While the code written for interface creation and interface<==>entity link is generic, currently I added support only for the type of interface currently used at the existing MC graphs: device node interfaces. We should add other types of interfaces in a future patchset. For example, we need to add support for network interfaces in order to fulfill the needs of the DVB subsystem. We'll also need to add support for sysfs interfaces in order to support IIO and remote controllers. Those API changes are aligned with the RFC for the userspace API proposed by Hans Verkuil: http://www.spinics.net/lists/linux-media/msg92166.html The only difference is that I'm using a single counter to generate an unique object ID, while Hans proposal is to use one per object type. As explained on my comments on the last patch series, the rationale is to simply simplify the code, helping to make the internal API changes clearer. We can change this latter before adding support for the userspace API. I suspect that we'll also need another type to represent groups of objects, but this will be covered on future patches if/when needed. No userspace API changes here, just changes at the internal structs that contains the media graph objects and some new helper functions. =========== Future work =========== I think that, after changing the MC core to support the new proposed API, a next step would be to simplify the internal representation of the media objects, in order to make it easier to be reused on other subsystems like IIO and to spend less memory. With that regards, I think that we can get rid of some fields at the existing structures: struct media_link.reverse - Currently we create two copies of the same link, in order to use at the graph traversal. I think we can remove it and use just one copy; struct media_entity - well, there are several things that we can get hid there: - parent - we're already storing it at the objects; - id - we have already an unique ID at the objects; - type - this should be replaced by properties; - revision - not used, afaikt; - group_id - groups should really be a new object type that will have the list of object IDs that belong to the group. - num_links/num_backlinks - those are used only at the userspace interface, but we need to track link creation/removal just to feed those things. I would remove those and add a logic at media_device.c to count; - num_pads - if we convert pads to lists (with seems to be the best thing, as not all entities need pads), then we can get rid of this too; - union info - this should be retrieved via the interface, and not via the entity. Yet, the above are suggestions for some future next steps. I won't probably address the above, except if needed in order to support the DVB or ALSA needs. Mauro Carvalho Chehab (16): media: Add some fields to store graph objects media: Add a common embeed struct for all media graph objects media: add functions to inialize media_graph_obj media: ensure that entities will have an object ID media: initialize PAD objects media: initialize the graph object inside the media links media: get rid of unused "extra_links" param on media_entity_init() media: convert links from array to list media: use media_graph_obj for link endpoints media: rename link source/sink to pad0_source/pad1_sink media: rename the function that create pad links media: move __media_entity_remove_link to avoid prototype media: make the internal function to create links more generic media: add a generic function to remove a link media: rename media_entity_remove_foo functions media: add functions to allow creating interfaces Documentation/media-framework.txt | 2 +- Documentation/video4linux/v4l2-framework.txt | 4 +- Documentation/zh_CN/video4linux/v4l2-framework.txt | 4 +- drivers/media/dvb-core/dvb_frontend.c | 10 +- drivers/media/dvb-core/dvbdev.c | 10 +- drivers/media/i2c/ad9389b.c | 2 +- drivers/media/i2c/adp1653.c | 2 +- drivers/media/i2c/adv7180.c | 2 +- drivers/media/i2c/adv7511.c | 2 +- drivers/media/i2c/adv7604.c | 2 +- drivers/media/i2c/adv7842.c | 2 +- drivers/media/i2c/as3645a.c | 2 +- drivers/media/i2c/cx25840/cx25840-core.c | 2 +- drivers/media/i2c/lm3560.c | 2 +- drivers/media/i2c/lm3646.c | 2 +- drivers/media/i2c/m5mols/m5mols_core.c | 2 +- drivers/media/i2c/mt9m032.c | 2 +- drivers/media/i2c/mt9p031.c | 2 +- drivers/media/i2c/mt9t001.c | 2 +- drivers/media/i2c/mt9v032.c | 2 +- drivers/media/i2c/noon010pc30.c | 2 +- drivers/media/i2c/ov2659.c | 2 +- drivers/media/i2c/ov9650.c | 2 +- drivers/media/i2c/s5c73m3/s5c73m3-core.c | 8 +- drivers/media/i2c/s5k4ecgx.c | 2 +- drivers/media/i2c/s5k5baf.c | 6 +- drivers/media/i2c/s5k6a3.c | 2 +- drivers/media/i2c/s5k6aa.c | 2 +- drivers/media/i2c/smiapp/smiapp-core.c | 8 +- drivers/media/i2c/tc358743.c | 2 +- drivers/media/i2c/tvp514x.c | 2 +- drivers/media/i2c/tvp7002.c | 2 +- drivers/media/media-device.c | 47 ++- drivers/media/media-entity.c | 363 ++++++++++++++------- drivers/media/platform/exynos4-is/fimc-capture.c | 4 +- drivers/media/platform/exynos4-is/fimc-isp-video.c | 2 +- drivers/media/platform/exynos4-is/fimc-isp.c | 2 +- drivers/media/platform/exynos4-is/fimc-lite.c | 4 +- drivers/media/platform/exynos4-is/fimc-m2m.c | 2 +- drivers/media/platform/exynos4-is/media-dev.c | 18 +- drivers/media/platform/exynos4-is/mipi-csis.c | 2 +- drivers/media/platform/omap3isp/isp.c | 22 +- drivers/media/platform/omap3isp/ispccdc.c | 6 +- drivers/media/platform/omap3isp/ispccp2.c | 4 +- drivers/media/platform/omap3isp/ispcsi2.c | 4 +- drivers/media/platform/omap3isp/isppreview.c | 6 +- drivers/media/platform/omap3isp/ispresizer.c | 6 +- drivers/media/platform/omap3isp/ispstat.c | 2 +- drivers/media/platform/omap3isp/ispvideo.c | 2 +- drivers/media/platform/s3c-camif/camif-capture.c | 4 +- drivers/media/platform/s3c-camif/camif-core.c | 4 +- drivers/media/platform/vsp1/vsp1_drv.c | 4 +- drivers/media/platform/vsp1/vsp1_entity.c | 2 +- drivers/media/platform/vsp1/vsp1_rpf.c | 2 +- drivers/media/platform/vsp1/vsp1_video.c | 2 +- drivers/media/platform/vsp1/vsp1_wpf.c | 2 +- drivers/media/platform/xilinx/xilinx-dma.c | 2 +- drivers/media/platform/xilinx/xilinx-tpg.c | 2 +- drivers/media/platform/xilinx/xilinx-vipp.c | 4 +- drivers/media/usb/cx231xx/cx231xx-cards.c | 6 +- drivers/media/usb/cx231xx/cx231xx-video.c | 18 +- drivers/media/usb/uvc/uvc_entity.c | 6 +- drivers/media/v4l2-core/tuner-core.c | 2 +- drivers/media/v4l2-core/v4l2-device.c | 2 +- drivers/media/v4l2-core/v4l2-flash-led-class.c | 2 +- drivers/media/v4l2-core/v4l2-subdev.c | 6 +- drivers/staging/media/davinci_vpfe/dm365_ipipe.c | 2 +- drivers/staging/media/davinci_vpfe/dm365_ipipeif.c | 4 +- drivers/staging/media/davinci_vpfe/dm365_isif.c | 4 +- drivers/staging/media/davinci_vpfe/dm365_resizer.c | 14 +- .../staging/media/davinci_vpfe/vpfe_mc_capture.c | 10 +- drivers/staging/media/davinci_vpfe/vpfe_video.c | 2 +- drivers/staging/media/omap4iss/iss.c | 20 +- drivers/staging/media/omap4iss/iss_csi2.c | 6 +- drivers/staging/media/omap4iss/iss_ipipe.c | 2 +- drivers/staging/media/omap4iss/iss_ipipeif.c | 4 +- drivers/staging/media/omap4iss/iss_resizer.c | 4 +- drivers/staging/media/omap4iss/iss_video.c | 2 +- include/media/media-device.h | 4 + include/media/media-entity.h | 139 +++++++- 80 files changed, 577 insertions(+), 306 deletions(-) -- 2.4.3 -- 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
