linux/include
Stephen Warren 5d61b165c8 of: Allow busses with #size-cells=0
It's quite legitimate for a DT node to specify #size-cells=0. One example
is a node that's used to collect a number of non-memory-mapped devices.
In that scenario, there may be multiple child nodes with the same name
(type) thus necessitating the use of unit addresses in node names, and
reg properties:

/ {
	regulators {
		compatible = "simple-bus";
		#address-cells = <1>;
		#size-cells = <0>;

		regulator@0 {
			compatible = "regulator-fixed";
			reg = <0>;
			...
		};

		regulator@1 {
			compatible = "regulator-fixed";
			reg = <1>;
			...
		};

		...
	};
};

However, #size-cells=0 prevents translation of reg property values into
the parent node's address space. In turn, this triggers the kernel to
emit error messages during boot, such as:

    prom_parse: Bad cell count for /regulators/regulator@0

To prevent printing these error messages for legitimate DT content, a
number of changes are made:

1) of_get_address()/of_get_pci_address() are modified only to validate
   the value of #address-cells, and not #size-cells.

2) of_can_translate_address() is added to indicate whether address
   translation is possible.

3) of_device_make_bus_id() is modified to name devices based on the
   translated address only where possible, and otherwise fall back to
   using the (first cell of the) raw untranslated address.

4) of_device_alloc() is modified to create memory resources for a device
   only if the address can be translated into the CPU's address space.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2012-08-03 08:01:46 -05:00
..
acpi Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux 2012-07-26 14:28:55 -07:00
asm-generic Merge branch 'akpm' (Andrew's patch-bomb) 2012-07-30 17:25:34 -07:00
crypto
drm drm/exynos: add property for plane zpos 2012-07-27 11:13:54 +09:00
keys
linux of: Allow busses with #size-cells=0 2012-08-03 08:01:46 -05:00
math-emu
media [media] v4l2: add core support for the new VIDIOC_ENUM_FREQ_BANDS ioctl 2012-07-30 20:23:05 -03:00
memory
misc
mtd
net Merge branch 'akpm' (Andrew's patch-bomb) 2012-07-31 19:25:39 -07:00
pcmcia
ras
rdma Merge branches 'cma', 'cxgb4', 'misc', 'mlx4-sriov', 'mlx-cleanups', 'ocrdma' and 'qib' into for-linus 2012-07-22 23:26:17 -07:00
rxrpc
scsi Merge branch 'master' [vanilla Linus master] into libata-dev.git/upstream 2012-07-25 15:58:48 -04:00
sound Sound fixes for 3.6-rc1 2012-08-01 10:42:26 -07:00
target target: Allow for target_submit_cmd() returning errors 2012-07-17 17:05:05 -07:00
trace Merge branch 'akpm' (Andrew's patch-bomb) 2012-07-31 19:25:39 -07:00
video video: da8xx-fb: configure FIFO threshold to reduce underflow errors 2012-07-29 01:11:09 +00:00
xen xen PVonHVM: move shared_info to MMIO before kexec 2012-07-19 15:52:05 -04:00
Kbuild