[PATCH] spi: tegra: don't treat NULL clk as an error

Russell King - ARM Linux linux at arm.linux.org.uk
Mon Jan 10 17:25:24 EST 2011


On Mon, Jan 10, 2011 at 10:18:02PM +0000, Russell King - ARM Linux wrote:
> On Mon, Jan 10, 2011 at 01:58:12PM -0700, Grant Likely wrote:
> > On Mon, Jan 10, 2011 at 4:05 AM, Jamie Iles <jamie at jamieiles.com> wrote:
> > > Some platforms have been known to return NULL from clk_get() if they
> > > support only a single struct clk.  Whilst tegra doesn't do this, make
> > > the drivers consistent with others.
> > >
> > > Cc: Erik Gilling <konkers at android.com>
> > > Signed-off-by: Jamie Iles <jamie at jamieiles.com>
> > 
> > Hi James,
> > 
> > If NULL does get returned, say due to a future change to the clock
> > code, then this change causes the driver to oops.  I'm not going to
> > apply this patch.
> 
> Please apply it - the clock API just defines struct clk as a cookie
> where errors are IS_ERR/PTR_ERR.  Other values must be considered by
> drivers as perfectly valid, including NULL.

Also note that drivers have no business ever dereferencing struct clks.
So if they oops, that's their own fault for dereferencing something
that they shouldn't.



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