On Tue, 20 May 2014 13:30:02 -0500, Rob Herring <robherring2@xxxxxxxxx> wrote: > On Tue, May 20, 2014 at 1:50 AM, Grant Likely <grant.likely@xxxxxxxxxxxx> wrote: > > On Sun, 18 May 2014 18:11:07 -0500, Rob Herring <robherring2@xxxxxxxxx> wrote: > >> On Sun, May 18, 2014 at 12:01 PM, Ezequiel Garcia > >> <ezequiel@xxxxxxxxxxxxxxxxxxxx> wrote: > >> > When creating a device object for a devicetree node, the device name > >> > is created by using the node name and the 'reg' property, to make a name > >> > such as "a000.foo_device". > >> > > >> > For certain devices without an associated address, and hence no 'reg' property, > >> > the current code attempts to make a unique name, by using a global integer. > >> > Names look like "foo_device.1", "bar_device.2", and so on. > >> > Examples of such devices are: gpio-keys', backlights and rotary-encoders. > >> > > >> > The system cannot know such devices name before hand, given they are determined > >> > by the kernel probe order and by the nodes present in the devicetree. This can > >> > be problematic, on systems that are tied to the device's name, e.g. when > >> > catching hotplug events. > > > > The device's uevent file in sysfs contains both the ->name and > > ->full_name values for a node. Does that help you? > > > > The big problem is not the structure under /sys/devices, but rather the > > symlinks to devices that appear under /sys/bus/*/devices. If two leaf > > nodes have the same name, then they will conflict when they get added to > > a bus_type's array of devices. > > > > Another way to handle it is to only add the suffix when a conflict > > actually occurs. That requires checking first whether or not a name will > > conflict and ammending it only when that happens. I don't know if that > > can be done nicely. I'll take a look. > > That was my idea as well and to move to a local number so you have > something like deviceA, deviceA.1, deviceB, deviceB.1 (maybe the > number is always appended). Perhaps a random number instead so no one > expects the names to be an ABI. ;) Another idea: how about fix the name to alwasy be the final component of the path name, followed by phandle. Anything that doesn't have a phandle can be assigned one at boot. That would guarantee uniqueness without the cost of trying to find duplicates. for example: uart@10043000:0012 g. -- 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
