On Wed, Mar 21, 2012 at 2:07 AM, Russell King - ARM Linux
[off-list ref] wrote:

On Tue, Mar 20, 2012 at 10:45:36PM -0700, Turquette, Mike wrote:

quoted

IIRC, that discussion was with respect to the .parent member of struct
clk. ?It was decided that having .parent = NULL does not imply that a
clock is a root clock, but instead we rely on the CLK_IS_ROOT flag. ?I
can't think of any other instance where a NULL clk when returned from
a registration function would be useful.

No. ?What I've been saying is that in _drivers_ which use clk_get(),
the error range is defined by IS_ERR(clk). ?Every other value of
clk must be assumed by the driver to be valid, no ifs or buts.

Drivers certainly might make calls to clk_register_foo, despite it
being outside of the traditional clock api.  For the sake of
consistency I'll convert the clk_register_foo functions to return
error codes.

Regards,
Mike