soc: fsl: dpio: add a device_link at dpaa2_io_service_register

Automatically add a device link between the actual device requesting the
dpaa2_io_service_register and the underlying dpaa2_io used. This link
will ensure that when a DPIO device, which is indirectly used by other
devices, is unbound any consumer devices will be also unbound from their
drivers.

For example, any DPNI, bound to the dpaa2-eth driver, which is using
DPIO devices will be unbound before its supplier device.

Also, add a new parameter to the dpaa2_io_service_[de]register functions
to specify the requesting device (ie the consumer).

Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Reviewed-by: Horia Geanta <horia.geanta@nxp.com>
Reviewed-by: Ioana Radulescu <ruxandra.radulescu@nxp.com>
Signed-off-by: Li Yang <leoyang.li@nxp.com>

1 files changed, 14 insertions, 2 deletions

diff --git a/drivers/soc/fsl/dpio/dpio-service.c b/drivers/soc/fsl/dpio/dpio-service.c
index 52d800aa4774..bc801934602a 100644
--- a/drivers/soc/fsl/dpio/dpio-service.c
+++ b/drivers/soc/fsl/dpio/dpio-service.c
@@ -237,6 +237,7 @@ EXPORT_SYMBOL(dpaa2_io_get_cpu);
  *                               notifications on the given DPIO service.
  * @d:   the given DPIO service.
  * @ctx: the notification context.
+ * @dev: the device that requests the register
  *
  * The caller should make the MC command to attach a DPAA2 object to
  * a DPIO after this function completes successfully.  In that way:
@@ -251,14 +252,20 @@ EXPORT_SYMBOL(dpaa2_io_get_cpu);
  * Return 0 for success, or -ENODEV for failure.
  */
 int dpaa2_io_service_register(struct dpaa2_io *d,
-			      struct dpaa2_io_notification_ctx *ctx)
+			      struct dpaa2_io_notification_ctx *ctx,
+			      struct device *dev)
 {
+	struct device_link *link;
 	unsigned long irqflags;
 
 	d = service_select_by_cpu(d, ctx->desired_cpu);
 	if (!d)
 		return -ENODEV;
 
+	link = device_link_add(dev, d->dev, DL_FLAG_AUTOREMOVE_CONSUMER);
+	if (!link)
+		return -EINVAL;
+
 	ctx->dpio_id = d->dpio_desc.dpio_id;
 	ctx->qman64 = (u64)(uintptr_t)ctx;
 	ctx->dpio_private = d;
@@ -279,12 +286,14 @@ EXPORT_SYMBOL_GPL(dpaa2_io_service_register);
  * dpaa2_io_service_deregister - The opposite of 'register'.
  * @service: the given DPIO service.
  * @ctx: the notification context.
+ * @dev: the device that requests to be deregistered
  *
  * This function should be called only after sending the MC command to
  * to detach the notification-producing device from the DPIO.
  */
 void dpaa2_io_service_deregister(struct dpaa2_io *service,
-				 struct dpaa2_io_notification_ctx *ctx)
+				 struct dpaa2_io_notification_ctx *ctx,
+				 struct device *dev)
 {
 	struct dpaa2_io *d = ctx->dpio_private;
 	unsigned long irqflags;
@@ -295,6 +304,9 @@ void dpaa2_io_service_deregister(struct dpaa2_io *service,
 	spin_lock_irqsave(&d->lock_notifications, irqflags);
 	list_del(&ctx->node);
 	spin_unlock_irqrestore(&d->lock_notifications, irqflags);
+
+	if (dev)
+		device_link_remove(dev, d->dev);
 }
 EXPORT_SYMBOL_GPL(dpaa2_io_service_deregister);