mfd: core: redo ACPI matching of the children devices

There is at least one board on the market, i.e. Intel Galileo Gen2, that uses
_ADR to distinguish the devices under one actual device. Due to this we have to
improve the quirk in the MFD core to handle that board.

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

1 files changed, 8 insertions, 3 deletions

diff --git a/Documentation/acpi/enumeration.txt b/Documentation/acpi/enumeration.txt
index b731b292e812..a91ec5af52df 100644
--- a/Documentation/acpi/enumeration.txt
+++ b/Documentation/acpi/enumeration.txt
@@ -347,13 +347,18 @@ For the first case, the MFD drivers do not need to do anything. The
 resulting child platform device will have its ACPI_COMPANION() set to point
 to the parent device.
 
-If the ACPI namespace has a device that we can match using an ACPI id,
-the id should be set like:
+If the ACPI namespace has a device that we can match using an ACPI id or ACPI
+adr, the cell should be set like:
+
+        static struct mfd_cell_acpi_match my_subdevice_cell_acpi_match = {
+                .pnpid = "XYZ0001",
+                .adr = 0,
+        };
 
         static struct mfd_cell my_subdevice_cell = {
                 .name = "my_subdevice",
                 /* set the resources relative to the parent */
-                .acpi_pnpid = "XYZ0001",
+                .acpi_match = &my_subdevice_cell_acpi_match,
         };
 
 The ACPI id "XYZ0001" is then used to lookup an ACPI device directly under