platform: introduce OF style 'modalias' support for platform bus

Fix a problem that, the platform bus supports the OF style modalias
in .uevent() call, but not in its device 'modalias' sysfs attribute.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index 2f4aea2428b2..bc78848dd59a 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -679,6 +679,10 @@ static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
         struct platform_device  *pdev = to_platform_device(dev);
         int len;
 
+        len = of_device_get_modalias(dev, buf, PAGE_SIZE -1);
+        if (len != -ENODEV)
+                return len;
+
         len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
         if (len != -ENODEV)
                 return len;