On Tue, 9 Oct 2018 at 11:39, Rafael J. Wysocki [off-list ref] wrote:

On Tue, Oct 9, 2018 at 7:27 PM Mathieu Poirier
[off-list ref] wrote:

quoted

Hi Silesh,

On Tue, Oct 09, 2018 at 03:47:24PM +0530, Silesh C V wrote:

quoted

Some drivers need to find the device on a bus having a specific firmware
node. Currently, such drivers have their own implementations to do this.
Provide a helper similar to bus_find_device_by_name so that each driver
does not have to reinvent this.

Signed-off-by: Silesh C V <redacted>
---
Changes since v2:
      - make use of dev_fwnode in match_fwnode.

 drivers/base/bus.c     | 20 ++++++++++++++++++++
 include/linux/device.h |  3 +++
 2 files changed, 23 insertions(+)

diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index 8bfd27e..a2f39db 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c

@@ -17,6 +17,7 @@
 #include <linux/string.h>
 #include <linux/mutex.h>
 #include <linux/sysfs.h>
+#include <linux/property.h>
 #include "base.h"
 #include "power/power.h"

@@ -373,6 +374,25 @@ struct device *bus_find_device_by_name(struct bus_type *bus,
 }
 EXPORT_SYMBOL_GPL(bus_find_device_by_name);

+static int match_fwnode(struct device *dev, void *fwnode)
+{
+     return dev_fwnode(dev) == fwnode;
+}
+
+/**
+ * bus_find_device_by_fwnode - device iterator for locating a particular device
+ * having a specific firmware node
+ * @bus: bus type
+ * @start: Device to begin with
+ * @fwnode: firmware node of the device to match
+ */
+struct device *bus_find_device_by_fwnode(struct bus_type *bus, struct device *start,
+                                     struct fwnode_handle *fwnode)

I get the following when running checkpatch on your set:

mpoirier at xps15:~/work/linaro/coresight/kernel-maint$ ./scripts/checkpatch.pl
0001-Driver-core-add-bus_find_device_by_fwnode.patch
WARNING: line over 80 characters

Lines longer than 80 chars often are legitimate.  No need to send
extra reports about those cases in general.

In this case I don't see a reason not to abide to the guideline.
Wrapping the function declaration to 80 characters would be easy
without effecting code readability.

Mathieu

Thanks,
Rafael