On 21 July 2015 at 21:28, Rafael J. Wysocki [off-list ref] wrote:

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

quoted

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.

Thanks Sudeep.
So I'll take this dependency out and default PCC to 'n'. Think that
should work for all cases. Agree?

Thanks,
Ashwin.