hwrng: timeriomem - relax check on memory resource size (2a4bfd02) · Commits · 戴 / test

The timeriomem_rng driver only accesses the first 4 bytes of the given memory area and currently, it also forces that memory resource to be exactly 4 bytes in size. This, however, is problematic when used with device-trees that are generated from things like FPGA toolchains, where the minimum size of an exposed memory block may be something like 4k. Hence, let's only check for what's needed for the driver to operate properly; namely that we have enough memory available to read the random data from. Signed-off-by:

Daniel Mack <daniel@zonque.org> Signed-off-by:

Herbert Xu <herbert@gondor.apana.org.au>

Documentation/devicetree/bindings/rng/timeriomem_rng.txt

+1 −1

Original line number	Diff line number	Diff line
		@@ -12,7 +12,7 @@ Optional properties:
		which disables using this rng to automatically fill the kernel's
		entropy pool.

		N.B. currently 'reg' must be four bytes wide and aligned
		N.B. currently 'reg' must be at least four bytes wide and 32-bit aligned

		Example:

drivers/char/hw_random/timeriomem-rng.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -117,9 +117,9 @@ static int timeriomem_rng_probe(struct platform_device *pdev)
		if (!res)
		return -ENXIO;

		if (res->start % 4 != 0 \|\| resource_size(res) != 4) {
		if (res->start % 4 != 0 \|\| resource_size(res) < 4) {
		dev_err(&pdev->dev,
		"address must be four bytes wide and aligned\n");
		"address must be at least four bytes wide and 32-bit aligned\n");
		return -EINVAL;
		}

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