On 23 July 2014 13:55, Simon Glass sjg@chromium.org wrote:
In U-Boot it is pretty common to number devices from 0 and access them on the command line using this numbering. While it may come to pass that we will move away from this numbering, the possibility seems remote at present.
Given that devices within a uclass will have an implied numbering, it makes sense to build this into driver model as a core feature. The cost is fairly small in terms of code and data space.
With each uclass having numbered devices we can ask for SPI port 0 or serial port 1 and receive a single device.
Devices typically request a sequence number using aliases in the device tree. These are resolved when the device is probed, to deal with conflicts. Sequence numbers need not be sequential and holes are permitted.
At present there is no support for sequence numbers using static platform data. It could easily be added to 'struct driver_info' if needed, but it seems better to add features as we find a use for them, and the use of -1 to mean 'no sequence' makes the default value somewhat painful.
Signed-off-by: Simon Glass sjg@chromium.org
Applied to dm/master.