Hi Marek, We used to use of_reserved_mem_device_init() in such a context in GPU drivers: -------------------->8------------------- /* Get the optional framebuffer memory resource */ ret = of_reserved_mem_device_init(drm->dev); if (ret && ret != -ENODEV) return ret; -------------------->8-------------------
The point is we may have a dedicated reserved memory area or may not have (depends on a particular .dts). Our expectation is if reserved memory area is missing then of_reserved_mem_device_init() just returns -ENODEV and it used to work like this. Now with your commit 59ce4039727e "of: reserved_mem: add support for using more than one region for given device" behavior is different. of_reserved_mem_device_init_by_idx() has this: -------------------->8------------------- target = of_parse_phandle(np, "memory-region", idx); if (!target) return -EINVAL; -------------------->8------------------- So I'm wondering which part should be fixed:  1) of_reserved_mem itself or  2) users of of_reserved_mem_device_init() Any thoughts? Regards, Alexey