mfd: core: propagate device properties to sub devices drivers

BugLink: http://bugs.launchpad.net/bugs/1533035

In the similar way like we do for the platform data we propagate the device
properties. For example, in case of Intel LPSS drivers we may provide a
specific property to tell the actual device driver an additional information
such as platform name.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
(cherry picked from commit 4d215cab)
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

drivers/mfd/mfd-core.c

@@ -14,6 +14,7 @@
 #include <linux/kernel.h>
 #include <linux/platform_device.h>
 #include <linux/acpi.h>
+#include <linux/property.h>
 #include <linux/mfd/core.h>
 #include <linux/pm_runtime.h>
 #include <linux/slab.h>
@@ -192,6 +193,12 @@ static int mfd_add_device(struct device *parent, int id,
 			goto fail_alias;
 	}
 
+	if (cell->pset) {
+		ret = platform_device_add_properties(pdev, cell->pset);
+		if (ret)
+			goto fail_alias;
+	}
+
 	ret = mfd_platform_add_cell(pdev, cell, usage_count);
 	if (ret)
 		goto fail_alias;

include/linux/mfd/core.h

@@ -17,6 +17,7 @@
 #include <linux/platform_device.h>
 
 struct irq_domain;
+struct property_set;
 
 /* Matches ACPI PNP id, either _HID or _CID, or ACPI _ADR */
 struct mfd_cell_acpi_match {
@@ -44,6 +45,10 @@ struct mfd_cell {
 	/* platform data passed to the sub devices drivers */
 	void			*platform_data;
 	size_t			pdata_size;
+
+	/* device properties passed to the sub devices drivers */
+	const struct property_set *pset;
+
 	/*
 	 * Device Tree compatible string
 	 * See: Documentation/devicetree/usage-model.txt Chapter 2.2 for details