On 5/28/19 4:11 AM, Tomi Valkeinen wrote: > Hi, > > On 10/05/2019 22:42, Adam Ford wrote: >> Currently the source code is compiled using hard-coded values >> from CONFIG_OMAP2_DSS_MIN_FCK_PER_PCK. This patch allows this >> clock divider value to be moved to the device tree and be changed >> without having to recompile the kernel. >> >> Signed-off-by: Adam Ford <aford173@xxxxxxxxx> > > I understand why you want to do this, but I'm not sure it's a good idea. > It's really something the driver should figure out, and if we add it to > the DT, it effectively becomes an ABI. > > That said... I'm not sure how good of a job the driver could ever do, as > it can't know the future scaling needs of the userspace at the time it > is configuring the clock. And so, I'm not nacking this patch, but I > don't feel very good about this patch... > > The setting also affects all outputs (exluding venc), which may not be > what the user wants. Then again, I think this setting is really only > needed on OMAP2 & 3, which have only a single output. But that's the > same with the current kconfig option, of course. > > So, the current CONFIG_OMAP2_DSS_MIN_FCK_PER_PCK is an ugly hack, in my > opinion, and moving it to DT makes it a worse hack =). But I don't have > any good suggestions either. > Module param? Andrew > Tomi >
