On Wed, Feb 29, 2012 at 4:48 AM, Florian Tobias Schandinat <FlorianSchandinat@xxxxxx> wrote: > Hi Tomi, > > On 02/29/2012 10:30 AM, Tomi Valkeinen wrote: >> On Wed, 2012-02-29 at 10:13 +0000, Florian Tobias Schandinat wrote: >>> On 02/29/2012 08:48 AM, Tomi Valkeinen wrote: >>>> ovl->enable/disable are meant to be synchronous so that they can handle >>>> the configuration of fifo sizes. The current kernel doesn't configure >>>> fifo sizes yet, and so the code doesn't need to block to function (from >>>> omapdss driver's perspective). >>>> >>>> However, for the users of omapdss a non-blocking ovl->disable is >>>> confusing, because they don't know when the memory area is not used >>>> any more. >>>> >>>> Furthermore, when the fifo size configuration is added in the next merge >>>> window, the change from non-blocking to blocking could cause side >>>> effects to the users of omapdss. So by making the functions block >>>> already will keep them behaving in the same manner. >>> >>> Is there any difference to doing it now? >>> I agree that this should be fixed but if we can't avoid breaking users I'd >>> prefer to break them in a merge window not in late rc stage. Or did we introduce >>> these functions just in the last merge window? >> >> Yes, these were introduced in the merge window. And I explicitly said >> the functions are blocking so that they can perform their job. And just >> to clarify, the functions already use a mutex, so in that sense they are >> blocking. They just don't currently wait until the HW has finished with >> the overlay. > > okay, than I'll apply this patch as is. I was just worried about asking Linus to > pull something that is labled as "Breaks existing users" now, but that doesn't > look like an issue here. > I don't expect this change should break any existing users.. I think it is safe to call this a bug fix BR, -R > Best regards, > > Florian Tobias Schandinat > >> >> The problem was raised by Rob Clark, who's writing the omapdrm driver, >> as he doesn't have a way to ensure that the overlay has been truly >> disabled and the memory is is no longer in use. >> >> (I forgot to cc him for the patch, adding him now). >> >> Tomi >> > > -- > To unsubscribe from this list: send the line "unsubscribe linux-omap" 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-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
