On Tuesday, July 21, 2015 04:28:43 PM Sudeep Holla wrote:

Hi Rafael,

On 21/07/15 15:34, Rafael J. Wysocki wrote:

quoted

Hi Sudeep,

On Tue, Jul 21, 2015 at 11:23 AM, Sudeep Holla [off-list ref] wrote:

quoted

On 20/07/15 23:04, Rafael J. Wysocki wrote:

quoted

On Monday, July 20, 2015 03:22:37 PM Sudeep Holla wrote:

quoted

On 09/07/15 19:04, Ashwin Chaugule wrote:

quoted

CPPC is the first client to make use of the PCC Mailbox channel. So
enable it only when CPPC is also enabled.

This sounds like a reverse dependency to me. So if there's some client
unrelated to CPPC using PCC, CPPC_LIB needs to be selected to enable PCC
?

No.  The other client will need to select PCC too.

Yes the PCC users/clients selecting PCC is fine and that's already
done(i.e. ACPI_CPPC_LIB selects PCC). I still don't understand the need
for this change, also how will other clients possibly select PCC which
now depends on CPPC_LIB ? e.g. if we have

config ACPI_XYZ_LIB
         select PCC

config ACPI_XYZ
         select ACPI_XYZ_LIB

Won't this shout warning: (ACPI_XYZ_LIB && ACPI_CPPC_LIB) selects PCC
which has unmet direct dependencies (MAILBOX && ACPI && ACPI_CPPC_LIB)
if ACPI_CPPC_LIB is not selected ?

That depends on the "depends on" clauses used.  Selecting itself
doesn't cause any dependencies to appear.

Agreed and I am absolutely fine with that. But if you look at this 
patch, it does

config PCC
	bool "Platform Communication Channel Driver"
	depends on ACPI && ACPI_CPPC_LIB

My bad, I've evidently overlooked that.

If PPC is selected from ACPI_CPPC_LIB, the "depends on" above is
obviously not needed.

I am fine with ACPI_CPPC_LIB selecting PCC which is already done in
earlier patch. I am against making PCC depend on ACPI_CPPC_LIB.

OK, makes sense.  Sorry for the misunderstanding.

Thanks,
Rafael