On Mon, Feb 26, 2024 at 04:23:15AM +0200, Andy Shevchenko wrote: > On Sun, Feb 25, 2024 at 11:34 PM Chris Packham > <chris.packham@xxxxxxxxxxxxxxxxxxx> wrote: > > > > This series adds a driver for a 7 segment LED display. > > > > I'd like to get some feedback on how this could be extended to support >1 > > character. The driver as presented is sufficient for my hardware which only has > > a single character display but I can see that for this to be generically useful > > supporting more characters would be desireable. > > > > Earlier I posted an idea that the characters could be represended by > > sub-nodes[1] but there doesn't seem to be a way of having that and keeping the > > convenience of using devm_gpiod_get_array() (unless I've missed something). > > It seems you didn't know that the tree for auxdisplay has been changed. > Can you rebase your stuff on top of > https://git.kernel.org/pub/scm/linux/kernel/git/andy/linux-auxdisplay.git/log/?h=for-next? > It will reduce your code base by ~50%. I have just updated the branch so it adds one patch that changes the prototype of linedisp_register(). > WRT subnodes, you can go with device_for_each_child_node() and > retrieve gpio array per digit. It means you will have an array of > arrays of GPIOs. Btw, as Geert proposed for another 7-segment driver, we might gain from the display-width-chars property. But I think this property has to be parsed on top of line display library, no need to have it in each affected driver. > > [1] - https://lore.kernel.org/lkml/2a8d19ee-b18b-4b7c-869f-7d601cea30b6@xxxxxxxxxxxxxxxxxxx/ -- With Best Regards, Andy Shevchenko