Hi! > Here's a simple example. Start with: > * the altera-gpio driver built in to the kernel but not in the > device tree. > * raw fpga image at /lib/firmware/soc_system.rbf > * Load appropriate device tree overlay in configfs by doing > $ mkdir /config/device-tree/overlays/1 > $ echo socfpga_overlay.dtbo > /config/device-tree/overlays/1/path > * This results in the FPGA getting programmed and the altera > gpio driver getting probed. Nice! > +/* Find the fpga manager that is pointed to by a phandle */ > +struct fpga_manager *of_fpga_mgr_dev_lookup(struct device_node *node, > + const char *mgr_property, > + int *ret) > +{ > + struct fpga_manager *mgr; > + struct device_node *mgr_node; > + > + mgr_node = of_parse_phandle(node, mgr_property, 0); > + > + if (!mgr_node) { > + *ret = -ENODEV; > + return NULL; Could IS_ERR_OR_NULL() and friends be used to get reasonable calling convention? Thanks, Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- 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