Hi Greg,

On 2021/2/5 17:53, Greg KH wrote:

On Fri, Feb 05, 2021 at 05:44:12PM +0800, Yicong Yang wrote:

quoted

From: Junhao He <redacted>

Use subdir-ccflags-* instead of ccflags-* to inherit the debug
settings from Kconfig when traversing subdirectories.

That says what you do, but not _why_ you are doing it.

i'll illustrate the reason and reword the commit.

What does this offer in benefit of the existing way?  What is it fixing?
Why do this "churn"?

currently we have added ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG in the Makefile
of driver/base and driver/base/power, but not in the subdirectory
driver/base/firmware_loader. we cannot turn the debug on for subdirectory
firmware_loader if we config DEBUG_DRIVER and there is no kconfig option
for the it.

as there is no other debug config in the subdirectory of driver/base,
CONFIG_DEBUG_DRIVER may also mean turn on the debug in the subdirectories, so use
subdir-ccflags-* instead for the -DDEBUG will allow us to enable debug for all
the subdirectories.

Thanks,
Yicong

thanks,

greg k-h

.