On Thu, Dec 23, 2010 at 6:55 AM, Manjunath Hadli <manjunath.hadli@xxxxxx> wrote: > Please refer to this file for detailed documentation of > davinci vpbe v4l2 driver > > Signed-off-by: Manjunath Hadli <manjunath.hadli@xxxxxx> > Acked-by: Muralidharan Karicheri <m-karicheri2@xxxxxx> > Acked-by: Hans Verkuil <hverkuil@xxxxxxxxx> > --- > Documentation/video4linux/README.davinci-vpbe | 93 +++++++++++++++++++++++++ > 1 files changed, 93 insertions(+), 0 deletions(-) > create mode 100644 Documentation/video4linux/README.davinci-vpbe > > diff --git a/Documentation/video4linux/README.davinci-vpbe b/Documentation/video4linux/README.davinci-vpbe > new file mode 100644 > index 0000000..7a460b0 > --- /dev/null > +++ b/Documentation/video4linux/README.davinci-vpbe > @@ -0,0 +1,93 @@ > + > + VPBE V4L2 driver design > + ====================================================================== > + > + File partitioning > + ----------------- > + V4L2 display device driver > + drivers/media/video/davinci/vpbe_display.c > + drivers/media/video/davinci/vpbe_display.h > + > + VPBE display controller > + drivers/media/video/davinci/vpbe.c > + drivers/media/video/davinci/vpbe.h > + > + VPBE venc sub device driver > + drivers/media/video/davinci/vpbe_venc.c > + drivers/media/video/davinci/vpbe_venc.h > + drivers/media/video/davinci/vpbe_venc_regs.h > + > + VPBE osd driver > + drivers/media/video/davinci/vpbe_osd.c > + drivers/media/video/davinci/vpbe_osd.h > + drivers/media/video/davinci/vpbe_osd_regs.h > + > + Functional partitioning > + ----------------------- > + > + Consists of the following (in the same order as the list under file > + partitioning):- > + > + 1. V4L2 display driver > + Implements creation of video2 and video3 device nodes and > + provides v4l2 device interface to manage VID0 and VID1 layers. > + > + 2. Display controller > + Loads up VENC, OSD and external encoders such as ths8200. It provides > + a set of API calls to V4L2 drivers to set the output/standards > + in the VENC or external sub devices. It also provides > + a device object to access the services from OSD subdevice > + using sub device ops. The connection of external encoders to VENC LCD > + controller port is done at init time based on default output and standard > + selection or at run time when application change the output through > + V4L2 IOCTLs. > + > + When connected to an external encoder, vpbe controller is also responsible > + for setting up the interface between VENC and external encoders based on > + board specific settings (specified in board-xxx-evm.c). This allows > + interfacing external encoders such as ths8200. The setup_if_config() > + is implemented for this as well as configure_venc() (part of the next patch) > + API to set timings in VENC for a specific display resolution. As of this > + patch series, the interconnection and enabling and setting of the external > + encoders is not present, and would be a part of the next patch series. > + > + 3. VENC subdevice module > + Responsible for setting outputs provided through internal DACs and also > + setting timings at LCD controller port when external encoders are connected > + at the port or LCD panel timings required. When external encoder/LCD panel > + is connected, the timings for a specific standard/preset is retrieved from > + the board specific table and the values are used to set the timings in > + venc using non-standard timing mode. > + > + Support LCD Panel displays using the VENC. For example to support a Logic > + PD display, it requires setting up the LCD controller port with a set of > + timings for the resolution supported and setting the dot clock. So we could > + add the available outputs as a board specific entry (i.e add the "LogicPD" > + output name to board-xxx-evm.c). A table of timings for various LCDs > + supported can be maintained in the board specific setup file to support > + various LCD displays.As of this patch a basic driver is present, and this > + support for external encoders and displays forms a part of the next > + patch series. > + For 2. and 3., any plans to eventually migrate to a KMS interface? It seems like a lot of device specific controls here. Alex > + 4. OSD module > + OSD module implements all OSD layer management and hardware specific > + features. The VPBE module interacts with the OSD for enabling and > + disabling appropriate features of the OSD. > + > + Current status:- > + > + A fully functional working version of the V4L2 driver is available. This > + driver has been tested with NTSC and PAL standards and buffer streaming. > + > + Following are TBDs. > + > + vpbe display controller > + - Add support for external encoders. > + - add support for selecting external encoder as default at probe time. > + > + vpbe venc sub device > + - add timings for supporting ths8200 > + - add support for LogicPD LCD. > + > + FB drivers > + - Add support for fbdev drivers.- Ready and part of subsequent patches. > -- > 1.6.2.4 > > -- > 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 > -- 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
