tree 908e4ca051d1936ec6dbdca0f300165cd061cfcc
parent 0d7412ed1f5dc0858eb4f29650a8c9c5cce8b285
author Boris Brezillon <boris.brezillon@bootlin.com> 1523400270 +0200
committer Mark Brown <broonie@kernel.org> 1524747209 +0100
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spi: Check presence the of ->transfer[_xxx]() before registering a controller

Right now, no checks are done on the presence of a ->transfer[_xxx]()
method, which can lead to a NULL pointer dereference when someone
starts sending something on the bus.

Do the check at registration time and refuse to add the controller if
all ->transfer[_xxx]() pointers are NULL.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>