staging: most: remove device from interface structure

This patch makes the adapter drivers use their own device structures
when registering a most interface with the core module.
With this the module that actually operates the physical device is the
owner of the device.

Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
Link: https://lore.kernel.org/r/1579793906-5054-2-git-send-email-christian.gromm@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

4 files changed, 38 insertions, 33 deletions

diff --git a/drivers/staging/most/core.c b/drivers/staging/most/core.c
index bcad2525d94b..d0fe873ce67a 100644
--- a/drivers/staging/most/core.c
+++ b/drivers/staging/most/core.c
@@ -402,7 +402,7 @@ static ssize_t description_show(struct device *dev,
 				struct device_attribute *attr,
 				char *buf)
 {
-	struct most_interface *iface = to_most_interface(dev);
+	struct most_interface *iface = dev_get_drvdata(dev);
 
 	return snprintf(buf, PAGE_SIZE, "%s\n", iface->description);
 }
@@ -411,7 +411,7 @@ static ssize_t interface_show(struct device *dev,
 			      struct device_attribute *attr,
 			      char *buf)
 {
-	struct most_interface *iface = to_most_interface(dev);
+	struct most_interface *iface = dev_get_drvdata(dev);
 
 	switch (iface->interface) {
 	case ITYPE_LOOPBACK:
@@ -476,7 +476,7 @@ static int print_links(struct device *dev, void *data)
 	int offs = d->offs;
 	char *buf = d->buf;
 	struct most_channel *c;
-	struct most_interface *iface = to_most_interface(dev);
+	struct most_interface *iface = dev_get_drvdata(dev);
 
 	list_for_each_entry(c, &iface->p->channel_list, list) {
 		if (c->pipe0.comp) {
@@ -484,7 +484,7 @@ static int print_links(struct device *dev, void *data)
 					 PAGE_SIZE - offs,
 					 "%s:%s:%s\n",
 					 c->pipe0.comp->name,
-					 dev_name(&iface->dev),
+					 dev_name(iface->dev),
 					 dev_name(&c->dev));
 		}
 		if (c->pipe1.comp) {
@@ -492,7 +492,7 @@ static int print_links(struct device *dev, void *data)
 					 PAGE_SIZE - offs,
 					 "%s:%s:%s\n",
 					 c->pipe1.comp->name,
-					 dev_name(&iface->dev),
+					 dev_name(iface->dev),
 					 dev_name(&c->dev));
 		}
 	}
@@ -534,7 +534,7 @@ static struct most_channel *get_channel(char *mdev, char *mdev_ch)
 	dev = bus_find_device_by_name(&mc.bus, NULL, mdev);
 	if (!dev)
 		return NULL;
-	iface = to_most_interface(dev);
+	iface = dev_get_drvdata(dev);
 	list_for_each_entry_safe(c, tmp, &iface->p->channel_list, list) {
 		if (!strcmp(dev_name(&c->dev), mdev_ch))
 			return c;
@@ -1232,7 +1232,7 @@ static int disconnect_channels(struct device *dev, void *data)
 	struct most_channel *c, *tmp;
 	struct most_component *comp = data;
 
-	iface = to_most_interface(dev);
+	iface = dev_get_drvdata(dev);
 	list_for_each_entry_safe(c, tmp, &iface->p->channel_list, list) {
 		if (c->pipe0.comp == comp || c->pipe1.comp == comp)
 			comp->disconnect_channel(c->iface, c->channel_id);
@@ -1261,14 +1261,11 @@ int most_deregister_component(struct most_component *comp)
 }
 EXPORT_SYMBOL_GPL(most_deregister_component);
 
-static void release_interface(struct device *dev)
-{
-	dev_info(&mc.dev, "releasing interface dev %s...\n", dev_name(dev));
-}
-
 static void release_channel(struct device *dev)
 {
-	dev_info(&mc.dev, "releasing channel dev %s...\n", dev_name(dev));
+	struct most_channel *c = to_channel(dev);
+
+	kfree(c);
 }
 
 /**
@@ -1305,14 +1302,14 @@ int most_register_interface(struct most_interface *iface)
 	INIT_LIST_HEAD(&iface->p->channel_list);
 	iface->p->dev_id = id;
 	strscpy(iface->p->name, iface->description, sizeof(iface->p->name));
-	iface->dev.init_name = iface->p->name;
-	iface->dev.bus = &mc.bus;
-	iface->dev.parent = &mc.dev;
-	iface->dev.groups = interface_attr_groups;
-	iface->dev.release = release_interface;
-	if (device_register(&iface->dev)) {
+	iface->dev->bus = &mc.bus;
+	iface->dev->parent = &mc.dev;
+	iface->dev->groups = interface_attr_groups;
+	dev_set_drvdata(iface->dev, iface);
+	if (device_register(iface->dev)) {
 		dev_err(&mc.dev, "registering iface->dev failed\n");
 		kfree(iface->p);
+		put_device(iface->dev);
 		ida_simple_remove(&mdev_id, id);
 		return -ENOMEM;
 	}
@@ -1328,7 +1325,7 @@ int most_register_interface(struct most_interface *iface)
 		else
 			snprintf(c->name, STRING_SIZE, "%s", name_suffix);
 		c->dev.init_name = c->name;
-		c->dev.parent = &iface->dev;
+		c->dev.parent = iface->dev;
 		c->dev.groups = channel_attr_groups;
 		c->dev.release = release_channel;
 		iface->p->channel[i] = c;
@@ -1362,16 +1359,15 @@ int most_register_interface(struct most_interface *iface)
 	return 0;
 
 err_free_most_channel:
-	kfree(c);
+	put_device(&c->dev);
 
 err_free_resources:
 	while (i > 0) {
 		c = iface->p->channel[--i];
 		device_unregister(&c->dev);
-		kfree(c);
 	}
 	kfree(iface->p);
-	device_unregister(&iface->dev);
+	device_unregister(iface->dev);
 	ida_simple_remove(&mdev_id, id);
 	return -ENOMEM;
 }
@@ -1401,12 +1397,11 @@ void most_deregister_interface(struct most_interface *iface)
 		c->pipe1.comp = NULL;
 		list_del(&c->list);
 		device_unregister(&c->dev);
-		kfree(c);
 	}
 
 	ida_simple_remove(&mdev_id, iface->p->dev_id);
 	kfree(iface->p);
-	device_unregister(&iface->dev);
+	device_unregister(iface->dev);
 }
 EXPORT_SYMBOL_GPL(most_deregister_interface);
 
diff --git a/drivers/staging/most/dim2/dim2.c b/drivers/staging/most/dim2/dim2.c
index 15c6aa8fa1ea..fb704be6f4f8 100644
--- a/drivers/staging/most/dim2/dim2.c
+++ b/drivers/staging/most/dim2/dim2.c
@@ -854,8 +854,8 @@ static int dim2_probe(struct platform_device *pdev)
 	dev->most_iface.poison_channel = poison_channel;
 	dev->most_iface.request_netinfo = request_netinfo;
 	dev->most_iface.driver_dev = &pdev->dev;
+	dev->most_iface.dev = &dev->dev;
 	dev->dev.init_name = "dim2_state";
-	dev->dev.parent = &dev->most_iface.dev;
 
 	ret = most_register_interface(&dev->most_iface);
 	if (ret) {
diff --git a/drivers/staging/most/most.h b/drivers/staging/most/most.h
index d93c6cea3a17..232e01b7f5d2 100644
--- a/drivers/staging/most/most.h
+++ b/drivers/staging/most/most.h
@@ -229,7 +229,7 @@ struct mbo {
  * @priv Private field used by mostcore to store context information.
  */
 struct most_interface {
-	struct device dev;
+	struct device *dev;
 	struct device *driver_dev;
 	struct module *mod;
 	enum most_interface_type interface;
@@ -251,8 +251,6 @@ struct most_interface {
 	struct interface_private *p;
 };
 
-#define to_most_interface(d) container_of(d, struct most_interface, dev)
-
 /**
  * struct most_component - identifies a loadable component for the mostcore
  * @list: list_head
diff --git a/drivers/staging/most/usb/usb.c b/drivers/staging/most/usb/usb.c
index 35217ca65cbb..dcc78cd870b8 100644
--- a/drivers/staging/most/usb/usb.c
+++ b/drivers/staging/most/usb/usb.c
@@ -102,6 +102,7 @@ struct clear_hold_work {
  * @poll_work_obj: work for polling link status
  */
 struct most_dev {
+	struct device dev;
 	struct usb_device *usb_device;
 	struct most_interface iface;
 	struct most_channel_capability *cap;
@@ -123,6 +124,7 @@ struct most_dev {
 };
 
 #define to_mdev(d) container_of(d, struct most_dev, iface)
+#define to_mdev_from_dev(d) container_of(d, struct most_dev, dev)
 #define to_mdev_from_work(w) container_of(w, struct most_dev, poll_work_obj)
 
 static void wq_clear_halt(struct work_struct *wq_obj);
@@ -1023,6 +1025,12 @@ static void release_dci(struct device *dev)
 	kfree(dci);
 }
 
+static void release_mdev(struct device *dev)
+{
+	struct most_dev *mdev = to_mdev_from_dev(dev);
+
+	kfree(mdev);
+}
 /**
  * hdm_probe - probe function of USB device driver
  * @interface: Interface of the attached USB device
@@ -1061,6 +1069,7 @@ hdm_probe(struct usb_interface *interface, const struct usb_device_id *id)
 	mdev->link_stat_timer.expires = jiffies + (2 * HZ);
 
 	mdev->iface.mod = hdm_usb_fops.owner;
+	mdev->iface.dev = &mdev->dev;
 	mdev->iface.driver_dev = &interface->dev;
 	mdev->iface.interface = ITYPE_USB;
 	mdev->iface.configure = hdm_configure_channel;
@@ -1079,6 +1088,9 @@ hdm_probe(struct usb_interface *interface, const struct usb_device_id *id)
 		 usb_dev->config->desc.bConfigurationValue,
 		 usb_iface_desc->desc.bInterfaceNumber);
 
+	mdev->dev.init_name = mdev->description;
+	mdev->dev.parent = &interface->dev;
+	mdev->dev.release = release_mdev;
 	mdev->conf = kcalloc(num_endpoints, sizeof(*mdev->conf), GFP_KERNEL);
 	if (!mdev->conf)
 		goto err_free_mdev;
@@ -1152,7 +1164,7 @@ hdm_probe(struct usb_interface *interface, const struct usb_device_id *id)
 		}
 
 		mdev->dci->dev.init_name = "dci";
-		mdev->dci->dev.parent = &mdev->iface.dev;
+		mdev->dci->dev.parent = get_device(mdev->iface.dev);
 		mdev->dci->dev.groups = dci_attr_groups;
 		mdev->dci->dev.release = release_dci;
 		if (device_register(&mdev->dci->dev)) {
@@ -1166,7 +1178,7 @@ hdm_probe(struct usb_interface *interface, const struct usb_device_id *id)
 	mutex_unlock(&mdev->io_mutex);
 	return 0;
 err_free_dci:
-	kfree(mdev->dci);
+	put_device(&mdev->dci->dev);
 err_free_busy_urbs:
 	kfree(mdev->busy_urbs);
 err_free_ep_address:
@@ -1176,7 +1188,7 @@ err_free_cap:
 err_free_conf:
 	kfree(mdev->conf);
 err_free_mdev:
-	kfree(mdev);
+	put_device(&mdev->dev);
 err_out_of_memory:
 	if (ret == 0 || ret == -ENOMEM) {
 		ret = -ENOMEM;
@@ -1213,7 +1225,7 @@ static void hdm_disconnect(struct usb_interface *interface)
 	kfree(mdev->cap);
 	kfree(mdev->conf);
 	kfree(mdev->ep_address);
-	kfree(mdev);
+	put_device(&mdev->dev);
 }
 
 static struct usb_driver hdm_usb = {