On Wed, Dec 14, 2016 at 01:45:30PM +0100, Thomas Petazzoni wrote: > Hello, > > On Tue, 13 Dec 2016 23:55:00 -0800, Jaghathiswari Rankappagounder > Natarajan wrote: > > > Documentation for the binding which provides an interface for adding clock, > > data and clear signal GPIO lines to control seven segment display. > > > > The platform device driver provides an API for displaying on two 7-segment > > displays, and implements the required bit-banging. The hardware assumed is > > 74HC164 wired to two 7-segment displays. > > > > The character device driver implements the user-space API for letting a user > > write to two 7-segment displays including any conversion methods necessary > > to map the user input to two 7-segment displays. > > > > Adding clock, data and clear signal GPIO lines in the devicetree to control > > seven segment display on zaius platform. > > > > The platform driver matches on the device tree node; the platform driver also > > initializes the character device. > > > > Tested that the seven segment display works properly by writing to the > > character device file on a EVB AST2500 board which also has 74HC164 wired > > to two 7-segment displays. > > FWIW, I proposed a driver for seven segment displays back in 2013: > > http://lists.infradead.org/pipermail/linux-arm-kernel/2013-January/139986.html > > And the feedback from Greg KH was: we don't need a driver for that, do > it from userspace. See: > > http://lists.infradead.org/pipermail/linux-arm-kernel/2013-January/139992.html > > So: good luck :-) Did anyone ever write a library for this type of thing? Again, I don't want to see one-off drivers for random devices like this that should be able to all be controlled from userspace in a common manner. Much like we did for fingerprint readers a long long time ago... thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
