On Thu, 24 Jul 2014, Greg Kroah-Hartman wrote: > On Fri, Jul 25, 2014 at 12:04:58AM +0900, Alexandre Courbot wrote: > > The huge majority of GPIOs have their direction and initial value set > > right after being obtained by one of the gpiod_get() functions. The > > integer GPIO API had gpio_request_one() that took a convenience flags > > parameter allowing to specify an direction and value applied to the > > returned GPIO. This feature greatly simplifies client code and ensures > > errors are always handled properly. > > > > A similar feature has been requested for the gpiod API. Since GPIOs need > > a direction to be used anyway, we prefer to extend the existing > > functions instead of introducing new functions that would raise the > > number of gpiod getters to 16 (!). > > > > The drawback of this approach is that all gpiod clients need to be > > updated, but there aren't that many and the moment and this results in > > smaller (and hopefully safer) code. > > > > Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxx> > > --- > > This change will be difficult to apply without breaking things, but > > let's try to do it right. Hopefully the benefit will outweight the > > disturbance. > > > > This is a patch against -next to list and update all current gpiod > > consumers. Updates are trivial at first sight, but it would be nice to > > get as many acks as possible from the respective subsystem maintainers. > > > > I'm not sure how this could be applied harmlessly though - maybe through > > a dedicated branch for -next? Problem is that a lot of new code is not > > yet merged into mainline, and conflicts are very likely to occur. Linus, > > do you have any suggestion as to how this can be done without blood being > > spilled? > > Do this in 3 steps, not all at once. > > Make a new function that takes the new argument, get that merged > > Submit patches that convert drivers over to use the new function. > > Once all of those are merged, remove the old function. > > That way there are no "flag days" needed, and everyone is happy you > don't send out emails with 40+ people in the To: and Cc: lines :) +99999 -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel