clocksource: dw_apb_timer_of: return EPROBE_DEFER if no clock available

commit ("b0fc70ce1f02 arm64: berlin: Select DW_APB_TIMER_OF") added the
support for the dw_apb_timer into the arm64 defconfig. However, for some
platforms like the Intel Stratix10 and Agilex, the clock manager doesn't
get loaded until after the timer driver get loaded. Thus, the driver hits
the panic "No clock nor clock-frequency property for" because it cannot
properly get the clock.

This patch adds support for EPROBE_DEFER so the kernel can come back to
finish loading this timer driver.

Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
1 file changed