media: v4l2-core: introduce a helper to unregister a spi subdev

Introduce a new video4linux2 spi helper, to unregister a subdev.
This allows to get rid of some more ifdefs.

Signed-off-by: Ezequiel Garcia <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/v4l2-core/v4l2-device.c

···
 #include <linux/module.h>
 #include <linux/i2c.h>
 #include <linux/slab.h>
-#if defined(CONFIG_SPI)
-#include <linux/spi/spi.h>
-#endif
 #include <linux/videodev2.h>
 #include <media/v4l2-device.h>
 #include <media/v4l2-ctrls.h>
···
 			continue;
 		}
 #endif
-#if defined(CONFIG_SPI)
-		if (sd->flags & V4L2_SUBDEV_FL_IS_SPI) {
-			struct spi_device *spi = v4l2_get_subdevdata(sd);
-
-			if (spi && !spi->dev.of_node && !spi->dev.fwnode)
-				spi_unregister_device(spi);
-			continue;
-		}
-#endif
+		else if (sd->flags & V4L2_SUBDEV_FL_IS_SPI)
+			v4l2_spi_subdev_unregister(sd);
 	}
 	/* Mark as unregistered, thus preventing duplicate unregistrations */
 	v4l2_dev->name[0] = '\0';

drivers/media/v4l2-core/v4l2-spi.c

···
 #include <media/v4l2-common.h>
 #include <media/v4l2-device.h>
 
+void v4l2_spi_subdev_unregister(struct v4l2_subdev *sd)
+{
+	struct spi_device *spi = v4l2_get_subdevdata(sd);
+
+	if (spi && !spi->dev.of_node && !spi->dev.fwnode)
+		spi_unregister_device(spi);
+}
+
 void v4l2_spi_subdev_init(struct v4l2_subdev *sd, struct spi_device *spi,
 		const struct v4l2_subdev_ops *ops)
 {

include/media/v4l2-common.h

···
 void v4l2_spi_subdev_init(struct v4l2_subdev *sd, struct spi_device *spi,
 		const struct v4l2_subdev_ops *ops);
 
+/**
+ * v4l2_spi_subdev_unregister - Unregister a v4l2_subdev
+ *
+ * @sd: pointer to &struct v4l2_subdev
+ */
+void v4l2_spi_subdev_unregister(struct v4l2_subdev *sd);
+
 #else
 
 static inline struct v4l2_subdev *
···
 		     const struct v4l2_subdev_ops *ops)
 {}
 
+static inline void v4l2_spi_subdev_unregister(struct v4l2_subdev *sd)
+{}
 #endif
 
 /* ------------------------------------------------------------------------- */