the setup before the change was
- arch/powerpc/Kconfig had the PPC_CLOCK option, off by default
- depending on the PPC_CLOCK option the arch/powerpc/kernel/clock.c file
was built, which implements the clk.h API but always returns -ENOSYS
unless a platform registers specific callbacks
- the MPC52xx platform selected PPC_CLOCK but did not register any
callbacks, thus all clk.h API calls keep resulting in -ENOSYS errors
(which is OK, all peripheral drivers deal with the situation)
- the MPC512x platform selected PPC_CLOCK and registered specific
callbacks implemented in arch/powerpc/platforms/512x/clock.c, thus
provided real support for the clock API
- no other powerpc platform did select PPC_CLOCK
the situation after the change is
- the MPC512x platform implements the COMMON_CLK interface, and thus the
PPC_CLOCK approach in arch/powerpc/platforms/512x/clock.c has become
obsolete
- the MPC52xx platform still lacks genuine support for the clk.h API
while this is not a change against the previous situation (the error
code returned from COMMON_CLK stubs differs but every call still
results in an error)
- with all references gone, the arch/powerpc/kernel/clock.c wrapper and
the PPC_CLOCK option have become obsolete, as did the clk_interface.h
header file
the switch from PPC_CLOCK to COMMON_CLK is done for all platforms within
the same commit such that multiplatform kernels (the combination of 512x
and 52xx within one executable) keep working
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
7d71d5b2e8