fpga: mgr: Use standard dev_release for class driver

The FPGA manager class driver data structure is being treated as a
managed resource instead of using the standard dev_release call-back
function to release the class data structure. This change removes
the managed resource code for the freeing of the class data structure
and combines the create() and register() functions into a single
register() or register_full() function.

The register_full() function accepts an info data structure to provide
flexibility in passing optional parameters. The register() function
supports the current parameter list for users that don't require the
use of optional parameters.

The devm_fpga_mgr_register() function is retained, and the
devm_fpga_mgr_register_full() function is added.

Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Xu Yilun <yilun.xu@intel.com>
Acked-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Moritz Fischer <mdf@kernel.org>

1 files changed, 91 insertions, 124 deletions

diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
index aa30889e2320..d49a9ce34568 100644
--- a/drivers/fpga/fpga-mgr.c
+++ b/drivers/fpga/fpga-mgr.c
@@ -592,49 +592,49 @@ void fpga_mgr_unlock(struct fpga_manager *mgr)
 EXPORT_SYMBOL_GPL(fpga_mgr_unlock);
 
 /**
- * fpga_mgr_create - create and initialize an FPGA manager struct
+ * fpga_mgr_register_full - create and register an FPGA Manager device
  * @parent:	fpga manager device from pdev
- * @name:	fpga manager name
- * @mops:	pointer to structure of fpga manager ops
- * @priv:	fpga manager private data
+ * @info:	parameters for fpga manager
  *
- * The caller of this function is responsible for freeing the struct with
- * fpga_mgr_free().  Using devm_fpga_mgr_create() instead is recommended.
+ * The caller of this function is responsible for calling fpga_mgr_unregister().
+ * Using devm_fpga_mgr_register_full() instead is recommended.
  *
- * Return: pointer to struct fpga_manager or NULL
+ * Return: pointer to struct fpga_manager pointer or ERR_PTR()
  */
-struct fpga_manager *fpga_mgr_create(struct device *parent, const char *name,
-				     const struct fpga_manager_ops *mops,
-				     void *priv)
+struct fpga_manager *
+fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *info)
 {
+	const struct fpga_manager_ops *mops = info->mops;
 	struct fpga_manager *mgr;
 	int id, ret;
 
 	if (!mops) {
 		dev_err(parent, "Attempt to register without fpga_manager_ops\n");
-		return NULL;
+		return ERR_PTR(-EINVAL);
 	}
 
-	if (!name || !strlen(name)) {
+	if (!info->name || !strlen(info->name)) {
 		dev_err(parent, "Attempt to register with no name!\n");
-		return NULL;
+		return ERR_PTR(-EINVAL);
 	}
 
 	mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
 	if (!mgr)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	id = ida_simple_get(&fpga_mgr_ida, 0, 0, GFP_KERNEL);
-	if (id < 0)
+	if (id < 0) {
+		ret = id;
 		goto error_kfree;
+	}
 
 	mutex_init(&mgr->ref_mutex);
 
-	mgr->name = name;
-	mgr->mops = mops;
-	mgr->priv = priv;
+	mgr->name = info->name;
+	mgr->mops = info->mops;
+	mgr->priv = info->priv;
+	mgr->compat_id = info->compat_id;
 
-	device_initialize(&mgr->dev);
 	mgr->dev.class = fpga_mgr_class;
 	mgr->dev.groups = mops->groups;
 	mgr->dev.parent = parent;
@@ -645,6 +645,19 @@ struct fpga_manager *fpga_mgr_create(struct device *parent, const char *name,
 	if (ret)
 		goto error_device;
 
+	/*
+	 * Initialize framework state by requesting low level driver read state
+	 * from device.  FPGA may be in reset mode or may have been programmed
+	 * by bootloader or EEPROM.
+	 */
+	mgr->state = fpga_mgr_state(mgr);
+
+	ret = device_register(&mgr->dev);
+	if (ret) {
+		put_device(&mgr->dev);
+		return ERR_PTR(ret);
+	}
+
 	return mgr;
 
 error_device:
@@ -652,96 +665,36 @@ error_device:
 error_kfree:
 	kfree(mgr);
 
-	return NULL;
+	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL_GPL(fpga_mgr_create);
+EXPORT_SYMBOL_GPL(fpga_mgr_register_full);
 
 /**
- * fpga_mgr_free - free an FPGA manager created with fpga_mgr_create()
- * @mgr:	fpga manager struct
- */
-void fpga_mgr_free(struct fpga_manager *mgr)
-{
-	ida_simple_remove(&fpga_mgr_ida, mgr->dev.id);
-	kfree(mgr);
-}
-EXPORT_SYMBOL_GPL(fpga_mgr_free);
-
-static void devm_fpga_mgr_release(struct device *dev, void *res)
-{
-	struct fpga_mgr_devres *dr = res;
-
-	fpga_mgr_free(dr->mgr);
-}
-
-/**
- * devm_fpga_mgr_create - create and initialize a managed FPGA manager struct
+ * fpga_mgr_register - create and register an FPGA Manager device
  * @parent:	fpga manager device from pdev
  * @name:	fpga manager name
  * @mops:	pointer to structure of fpga manager ops
  * @priv:	fpga manager private data
  *
- * This function is intended for use in an FPGA manager driver's probe function.
- * After the manager driver creates the manager struct with
- * devm_fpga_mgr_create(), it should register it with fpga_mgr_register().  The
- * manager driver's remove function should call fpga_mgr_unregister().  The
- * manager struct allocated with this function will be freed automatically on
- * driver detach.  This includes the case of a probe function returning error
- * before calling fpga_mgr_register(), the struct will still get cleaned up.
+ * The caller of this function is responsible for calling fpga_mgr_unregister().
+ * Using devm_fpga_mgr_register() instead is recommended. This simple
+ * version of the register function should be sufficient for most users. The
+ * fpga_mgr_register_full() function is available for users that need to pass
+ * additional, optional parameters.
  *
- * Return: pointer to struct fpga_manager or NULL
+ * Return: pointer to struct fpga_manager pointer or ERR_PTR()
  */
-struct fpga_manager *devm_fpga_mgr_create(struct device *parent, const char *name,
-					  const struct fpga_manager_ops *mops,
-					  void *priv)
+struct fpga_manager *
+fpga_mgr_register(struct device *parent, const char *name,
+		  const struct fpga_manager_ops *mops, void *priv)
 {
-	struct fpga_mgr_devres *dr;
+	struct fpga_manager_info info = { 0 };
 
-	dr = devres_alloc(devm_fpga_mgr_release, sizeof(*dr), GFP_KERNEL);
-	if (!dr)
-		return NULL;
+	info.name = name;
+	info.mops = mops;
+	info.priv = priv;
 
-	dr->mgr = fpga_mgr_create(parent, name, mops, priv);
-	if (!dr->mgr) {
-		devres_free(dr);
-		return NULL;
-	}
-
-	devres_add(parent, dr);
-
-	return dr->mgr;
-}
-EXPORT_SYMBOL_GPL(devm_fpga_mgr_create);
-
-/**
- * fpga_mgr_register - register an FPGA manager
- * @mgr: fpga manager struct
- *
- * Return: 0 on success, negative error code otherwise.
- */
-int fpga_mgr_register(struct fpga_manager *mgr)
-{
-	int ret;
-
-	/*
-	 * Initialize framework state by requesting low level driver read state
-	 * from device.  FPGA may be in reset mode or may have been programmed
-	 * by bootloader or EEPROM.
-	 */
-	mgr->state = fpga_mgr_state(mgr);
-
-	ret = device_add(&mgr->dev);
-	if (ret)
-		goto error_device;
-
-	dev_info(&mgr->dev, "%s registered\n", mgr->name);
-
-	return 0;
-
-error_device:
-	ida_simple_remove(&fpga_mgr_ida, mgr->dev.id);
-
-	return ret;
+	return fpga_mgr_register_full(parent, &info);
 }
 EXPORT_SYMBOL_GPL(fpga_mgr_register);
 
@@ -765,14 +718,6 @@ void fpga_mgr_unregister(struct fpga_manager *mgr)
 }
 EXPORT_SYMBOL_GPL(fpga_mgr_unregister);
 
-static int fpga_mgr_devres_match(struct device *dev, void *res,
-				 void *match_data)
-{
-	struct fpga_mgr_devres *dr = res;
-
-	return match_data == dr->mgr;
-}
-
 static void devm_fpga_mgr_unregister(struct device *dev, void *res)
 {
 	struct fpga_mgr_devres *dr = res;
@@ -781,45 +726,67 @@ static void devm_fpga_mgr_unregister(struct device *dev, void *res)
 }
 
 /**
- * devm_fpga_mgr_register - resource managed variant of fpga_mgr_register()
- * @dev: managing device for this FPGA manager
- * @mgr: fpga manager struct
+ * devm_fpga_mgr_register_full - resource managed variant of fpga_mgr_register()
+ * @parent:	fpga manager device from pdev
+ * @info:	parameters for fpga manager
  *
- * This is the devres variant of fpga_mgr_register() for which the unregister
+ * This is the devres variant of fpga_mgr_register_full() for which the unregister
  * function will be called automatically when the managing device is detached.
  */
-int devm_fpga_mgr_register(struct device *dev, struct fpga_manager *mgr)
+struct fpga_manager *
+devm_fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *info)
 {
 	struct fpga_mgr_devres *dr;
-	int ret;
-
-	/*
-	 * Make sure that the struct fpga_manager * that is passed in is
-	 * managed itself.
-	 */
-	if (WARN_ON(!devres_find(dev, devm_fpga_mgr_release,
-				 fpga_mgr_devres_match, mgr)))
-		return -EINVAL;
+	struct fpga_manager *mgr;
 
 	dr = devres_alloc(devm_fpga_mgr_unregister, sizeof(*dr), GFP_KERNEL);
 	if (!dr)
-		return -ENOMEM;
+		return ERR_PTR(-ENOMEM);
 
-	ret = fpga_mgr_register(mgr);
-	if (ret) {
+	mgr = fpga_mgr_register_full(parent, info);
+	if (IS_ERR(mgr)) {
 		devres_free(dr);
-		return ret;
+		return mgr;
 	}
 
 	dr->mgr = mgr;
-	devres_add(dev, dr);
+	devres_add(parent, dr);
 
-	return 0;
+	return mgr;
+}
+EXPORT_SYMBOL_GPL(devm_fpga_mgr_register_full);
+
+/**
+ * devm_fpga_mgr_register - resource managed variant of fpga_mgr_register()
+ * @parent:	fpga manager device from pdev
+ * @name:	fpga manager name
+ * @mops:	pointer to structure of fpga manager ops
+ * @priv:	fpga manager private data
+ *
+ * This is the devres variant of fpga_mgr_register() for which the
+ * unregister function will be called automatically when the managing
+ * device is detached.
+ */
+struct fpga_manager *
+devm_fpga_mgr_register(struct device *parent, const char *name,
+		       const struct fpga_manager_ops *mops, void *priv)
+{
+	struct fpga_manager_info info = { 0 };
+
+	info.name = name;
+	info.mops = mops;
+	info.priv = priv;
+
+	return devm_fpga_mgr_register_full(parent, &info);
 }
 EXPORT_SYMBOL_GPL(devm_fpga_mgr_register);
 
 static void fpga_mgr_dev_release(struct device *dev)
 {
+	struct fpga_manager *mgr = to_fpga_manager(dev);
+
+	ida_simple_remove(&fpga_mgr_ida, mgr->dev.id);
+	kfree(mgr);
 }
 
 static int __init fpga_mgr_class_init(void)