On Wed, 11 Jan 2012, Bhupesh SHARMA wrote: > Hi Guennadi, > > > -----Original Message----- > > From: Guennadi Liakhovetski [mailto:g.liakhovetski@xxxxxx] > > Sent: Wednesday, January 11, 2012 5:18 PM > > To: Bhupesh SHARMA > > Cc: linux-media@xxxxxxxxxxxxxxx > > Subject: Re: Purpose of .init and .release methods in soc_camera > > framework > > > > Hi Bhupesh > > > > On Wed, 11 Jan 2012, Bhupesh SHARMA wrote: > > > > > Hi Guennadi, > > > > > > I was reading the latest soc_camera framework documentation (see > > [1]). > > > I can see on line 71 to 73 the following text: > > > > > > " .add and .remove methods are called when a sensor is attached to or > > detached > > > from the host, apart from performing host-internal tasks they shall > > also call > > > sensor driver's .init and .release methods respectively." > > > > > > Now, I was puzzled on seeing that none of the soc_camera bridge > > drivers ( > > > like PXA and SH Mobile) call the sensor's .init and .release from > > their > > > .add and .remove methods respectively. > > > > .init() and .release() methods were a part of the soc-camera client > > API. > > It has been removed with the migration to the v4l2-subdev API. > > Ok. So, can the documentation be updated to reflect the same. That documentation has more problems, than just that. It shall be updated at some point, yes... > > > Also I cannot trace these calls in soc_camera.c layer > > > > > > Actually, I am working on a camera sensor that requires certain > > > patches to be written to it before it can start working: > > > > > > - Now, if I write these patches in the _probe_ of the sensor driver > > (similar > > > to the ST VS6624 driver here : [2]), my sensor can work well for the > > 1st run > > > of the user-space application. But, if I launch the application again > > the patches > > > need to be written to the sensor again as I have implemented an 'icl- > > >power' routine > > > which basically turns ON and OFF the sensor by toggling its CE (chip > > enable pin). > > > > > > - As the soc_camera layer provides no explicit call to the camera > > sensor driver > > > when an _open_ is invoked from the userland, when and how should I > > write the > > > patch registers. > > > > > > I can only think of using the .init routine to initialize the sensor > > patch registers > > > in such a case. > > > > Why don't you perform that initialisation in your .power() method? > > You mean in the icl->power method? No, I mean the v4l2-subdev struct v4l2_subdev_core_ops::s_power() method, sorry for confusion. Thanks Guennadi --- Guennadi Liakhovetski, Ph.D. Freelance Open-Source Software Developer http://www.open-technology.de/ -- 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
