platform/surface: aggregator_cdev: Allow enabling of events from user-space

While events can already be enabled and disabled via the generic request
IOCTL, this bypasses the internal reference counting mechanism of the
controller. Due to that, disabling an event will turn it off regardless
of any other client having requested said event, which may break
functionality of that client.

To solve this, add IOCTLs wrapping the ssam_controller_event_enable()
and ssam_controller_event_disable() functions, which have been
previously introduced for this specific purpose.

Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210604134755.535590-6-luzmaximilian@gmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

1 files changed, 58 insertions, 0 deletions

diff --git a/drivers/platform/surface/surface_aggregator_cdev.c b/drivers/platform/surface/surface_aggregator_cdev.c
index dcda377896b7..7b86b36eaaa0 100644
--- a/drivers/platform/surface/surface_aggregator_cdev.c
+++ b/drivers/platform/surface/surface_aggregator_cdev.c
@@ -387,6 +387,58 @@ static long ssam_cdev_notif_unregister(struct ssam_cdev_client *client,
 	return ssam_cdev_notifier_unregister(client, desc.target_category);
 }
 
+static long ssam_cdev_event_enable(struct ssam_cdev_client *client,
+				   const struct ssam_cdev_event_desc __user *d)
+{
+	struct ssam_cdev_event_desc desc;
+	struct ssam_event_registry reg;
+	struct ssam_event_id id;
+	long ret;
+
+	/* Read descriptor from user-space. */
+	ret = copy_struct_from_user(&desc, sizeof(desc), d, sizeof(*d));
+	if (ret)
+		return ret;
+
+	/* Translate descriptor. */
+	reg.target_category = desc.reg.target_category;
+	reg.target_id = desc.reg.target_id;
+	reg.cid_enable = desc.reg.cid_enable;
+	reg.cid_disable = desc.reg.cid_disable;
+
+	id.target_category = desc.id.target_category;
+	id.instance = desc.id.instance;
+
+	/* Disable event. */
+	return ssam_controller_event_enable(client->cdev->ctrl, reg, id, desc.flags);
+}
+
+static long ssam_cdev_event_disable(struct ssam_cdev_client *client,
+				    const struct ssam_cdev_event_desc __user *d)
+{
+	struct ssam_cdev_event_desc desc;
+	struct ssam_event_registry reg;
+	struct ssam_event_id id;
+	long ret;
+
+	/* Read descriptor from user-space. */
+	ret = copy_struct_from_user(&desc, sizeof(desc), d, sizeof(*d));
+	if (ret)
+		return ret;
+
+	/* Translate descriptor. */
+	reg.target_category = desc.reg.target_category;
+	reg.target_id = desc.reg.target_id;
+	reg.cid_enable = desc.reg.cid_enable;
+	reg.cid_disable = desc.reg.cid_disable;
+
+	id.target_category = desc.id.target_category;
+	id.instance = desc.id.instance;
+
+	/* Disable event. */
+	return ssam_controller_event_disable(client->cdev->ctrl, reg, id, desc.flags);
+}
+
 
 /* -- File operations. ------------------------------------------------------ */
 
@@ -473,6 +525,12 @@ static long __ssam_cdev_device_ioctl(struct ssam_cdev_client *client, unsigned i
 		return ssam_cdev_notif_unregister(client,
 						  (struct ssam_cdev_notifier_desc __user *)arg);
 
+	case SSAM_CDEV_EVENT_ENABLE:
+		return ssam_cdev_event_enable(client, (struct ssam_cdev_event_desc __user *)arg);
+
+	case SSAM_CDEV_EVENT_DISABLE:
+		return ssam_cdev_event_disable(client, (struct ssam_cdev_event_desc __user *)arg);
+
 	default:
 		return -ENOTTY;
 	}