On Tue, Jul 18, 2017 at 12:53:12PM +0000, Hugues FRUCHET wrote: > > > On 07/18/2017 02:17 PM, H. Nikolaus Schaller wrote: > > Hi, > > > >> Am 18.07.2017 um 13:59 schrieb Hans Verkuil <hverkuil@xxxxxxxxx>: > >> > >> On 12/07/17 22:01, Sylwester Nawrocki wrote: > >>> Hi Hugues, > >>> > >>> On 07/03/2017 11:16 AM, Hugues Fruchet wrote: > >>>> This patchset enables OV9655 camera support. > >>>> > >>>> OV9655 support has been tested using STM32F4DIS-CAM extension board > >>>> plugged on connector P1 of STM32F746G-DISCO board. > >>>> Due to lack of OV9650/52 hardware support, the modified related code > >>>> could not have been checked for non-regression. > >>>> > >>>> First patches upgrade current support of OV9650/52 to prepare then > >>>> introduction of OV9655 variant patch. > >>>> Because of OV9655 register set slightly different from OV9650/9652, > >>>> not all of the driver features are supported (controls). Supported > >>>> resolutions are limited to VGA, QVGA, QQVGA. > >>>> Supported format is limited to RGB565. > >>>> Controls are limited to color bar test pattern for test purpose. > >>> > >>> I appreciate your efforts towards making a common driver but IMO it would be > >>> better to create a separate driver for the OV9655 sensor. The original driver > >>> is 1576 lines of code, your patch set adds half of that (816). There are > >>> significant differences in the feature set of both sensors, there are > >>> differences in the register layout. I would go for a separate driver, we > >>> would then have code easier to follow and wouldn't need to worry about possible > >>> regressions. I'm afraid I have lost the camera module and won't be able > >>> to test the patch set against regressions. > >>> > >>> IMHO from maintenance POV it's better to make a separate driver. In the end > >>> of the day we wouldn't be adding much more code than it is being done now. > >> > >> I agree. We do not have great experiences in the past with trying to support > >> multiple variants in a single driver (unless the diffs are truly small). > > > > Well, > > IMHO the diffs in ov965x are smaller (but untestable because nobody seems > > to have an ov9650/52 board) than within the bq27xxx chips, but I can dig out > > an old pdata based separate ov9655 driver and extend that to become DT compatible. > > > > I had abandoned that separate approach in favour of extending the ov965x driver. > > > > Have to discuss with Hugues how to proceed. > > > > BR and thanks, > > Nikolaus > > > > As Sylwester and Hans, I'm also in flavour of a separate driver, the > fact that register set seems similar but in fact is not and that we > cannot test for non-regression of 9650/52 are killer for me to continue > on a single driver. > We can now restart from a new fresh state of the art sensor driver > getting rid of legacy (pdata, old gpio, etc...). Agreed. I bet the result will look cleaner indeed although this wasn't one of the complex drivers. It'd be nice that someone was able to test the ov9650/2, too, drivers that are never used tend to break... -- Sakari Ailus e-mail: sakari.ailus@xxxxxx XMPP: sailus@xxxxxxxxxxxxxx
