On Thu, May 19, 2011 at 06:13:28PM +0300, Alex Gershgorin wrote: > Hi Michael, > > I liked the idea of a driver that returns fixed format and frame size. > It certainly could solve my problem. > On the other hand, from your correspondence to Laurent, I realized that it was already done work on improving V4L2 subdevs. > Michael patch of which you speak will help solve my problem without writing a special driver? > Advise in what direction to go in my case? Hi Alex, You still need a driver, but with the patches you can easily implement that as a driver for a platform device. The driver itself wouldn't have to do much more than to return a fixed format and size when queried. > > Regards, > > Alex Gershgorin > > > > -----Original Message----- > From: Laurent Pinchart [mailto:laurent.pinchart@xxxxxxxxxxxxxxxx] > Sent: Thursday, May 19, 2011 5:27 PM > To: Michael Jones > Cc: Alex Gershgorin; 'linux-media@xxxxxxxxxxxxxxx'; 'sakari.ailus@xxxxxx'; 'agersh@xxxxxxxxxx' > Subject: Re: FW: OMAP 3 ISP > > Hi Michael, > > On Thursday 19 May 2011 16:24:29 Michael Jones wrote: > > On 05/19/2011 03:56 PM, Laurent Pinchart wrote: > > > On Thursday 19 May 2011 15:44:18 Michael Jones wrote: > > >> On 05/19/2011 03:02 PM, Laurent Pinchart wrote: > > >>> On Thursday 19 May 2011 14:51:16 Alex Gershgorin wrote: > > >>>> Thanks Laurent, > > >>>> > > >>>> My video source is not the video camera and performs many other > > >>>> functions. For this purpose I have RS232 port. > > >>>> As for the video, it runs continuously and is not subject to control > > >>>> except for the power supply. > > >>> > > >>> As a quick hack, you can create an I2C driver for your video source > > >>> that doesn't access the device and just returns fixed format and frame > > >>> size. > > >>> > > >>> The correct fix is to implement support for platform subdevs in the > > >>> V4L2 core. > > >> > > >> I recently implemented support for platform V4L2 subdevs. Now that it > > >> sounds like others would be interested in this, I will try to polish it > > >> up and submit the patch for review in the next week or so. > > > > > > Great. This has been discussed during the V4L meeting in Warsaw, here are > > > a couple of pointers, to make sure we're going in the same direction. > > > > > > Bridge drivers should not care whether the subdev sits on an I2C, SPI, > > > platform or other bus. To achieve that, an abstraction layer must be > > > provided by the V4L2 core. Here's what I got in one of my trees: > > > > > > /* V4L2 core */ > > > > > > struct v4l2_subdev_i2c_board_info { > > > > > > struct i2c_board_info *board_info; > > > int i2c_adapter_id; > > > > > > }; > > > > > > enum v4l2_subdev_bus_type { > > > > > > V4L2_SUBDEV_BUS_TYPE_NONE, > > > V4L2_SUBDEV_BUS_TYPE_I2C, > > > V4L2_SUBDEV_BUS_TYPE_SPI, > > > > > > }; > > > > > > struct v4l2_subdev_board_info { > > > > > > enum v4l2_subdev_bus_type type; > > > union { > > > > > > struct v4l2_subdev_i2c_board_info i2c; > > > struct spi_board_info *spi; > > > > > > } info; > > > > > > }; > > > > > > /* OMAP3 ISP */ > > > > > > struct isp_v4l2_subdevs_group { > > > > > > struct v4l2_subdev_board_info *subdevs; > > > enum isp_interface_type interface; > > > union { > > > > > > struct isp_parallel_platform_data parallel; > > > struct isp_ccp2_platform_data ccp2; > > > struct isp_csi2_platform_data csi2; > > > > > > } bus; /* gcc < 4.6.0 chokes on anonymous union initializers */ > > > > > > }; > > > > > > struct isp_platform_data { > > > > > > struct isp_v4l2_subdevs_group *subdevs; > > > > > > }; > > > > > > The V4L2 core would need to provide a function to register a subdev based > > > on a v4l2_subdev_board_info structure. > > > > > > Is that in line with what you've done ? I can provide a patch that > > > implements this for I2C and SPI, and let you add platform subdevs if > > > that can help you. > > > > Hi Laurent, > > > > Yes, that looks very similar to what I've done. I was going to submit > > SPI support, too, which I also have, but it sounds like you've already > > done that? I'm currently still using a 2.6.38 tree based on an older > > media branch of yours, so I'm not familiar with any new changes there yet. > > > > I just need to know what I should use as my baseline. > > Please use mainline, now that the OMAP3 ISP driver has been merged :-) > > > I don't need to step on toes and submit something you've already done, so > > maybe you want to point me to a branch with the SPI stuff, and I'll just put > > the platform stuff on top of it? > > I'll send the SPI support patches to linux-media, as they haven't been > reviewed publicly yet. > > -- > Regards, > > Laurent Pinchart > > > __________ Information from ESET NOD32 Antivirus, version of virus signature database 6135 (20110519) __________ > > The message was checked by ESET NOD32 Antivirus. > > http://www.eset.com > > > > __________ Information from ESET NOD32 Antivirus, version of virus signature database 6135 (20110519) __________ > > The message was checked by ESET NOD32 Antivirus. > > http://www.eset.com > -- Sakari Ailus sakari dot ailus at iki dot fi -- 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
