[PATCH v3 0/8] fpga: Populate dev_release functions

[PATCH v3 0/8] fpga: Populate dev_release functions

[Russ Weight]

The FPGA framework has a convention of using managed resource functions
to allow parent drivers to manage the data structures allocated by the
class drivers. They use an empty *_dev_release() function to satisfy the
class driver.

This is inconsistent with linux driver model.

These changes populate the class dev_release callback functions while
maintaining the current API.  Additional changes are made to maintain
consistency with the driver model.

For more context on these changes, refer to this email thread:

https://marc.info/?l=linux-fpga&m=162127412218557&w=2

Changelog v2 -> v3:
  - Added Reviewed-by tags
  - Moved a "dev" to "parent" rename in the comment header for
    devm_fpga_region_create() from patch 8 to patch 5.

Changelog v1 -> v2:
  - Moved the renaming of "dev" to "parent" into a separate patch each for
    fpga-mgr, fpga-bridge, fpga-region.
  - Restored the call to fpga_mgr_free() in devm_*_mgr_release() instead of 
    changing it to put_device().
  - Replaced patch "fpga: altera-pr-ip: Remove function alt_pr_unregister"
    with "fpga: altera-pr-ip: Remove function alt_pr_unregister". This patch
    removes the alt_pr_unregister() function altogether, instead of just
    removing portions of it.

Russ Weight (8):
  fpga: altera-pr-ip: Remove function alt_pr_unregister
  fpga: stratix10-soc: Add missing fpga_mgr_free() call
  fpga: mgr: Rename dev to parent for parent device
  fpga: bridge: Rename dev to parent for parent device
  fpga: region: Rename dev to parent for parent device
  fpga: mgr: Use standard dev_release for class driver
  fpga: bridge: Use standard dev_release for class driver
  fpga: region: Use standard dev_release for class driver

 drivers/fpga/altera-pr-ip-core.c       | 10 -----
 drivers/fpga/fpga-bridge.c             | 46 ++++++++++-----------
 drivers/fpga/fpga-mgr.c                | 55 ++++++++++++--------------
 drivers/fpga/fpga-region.c             | 44 ++++++++++-----------
 drivers/fpga/stratix10-soc.c           |  1 +
 include/linux/fpga/altera-pr-ip-core.h |  1 -
 6 files changed, 71 insertions(+), 86 deletions(-)

-- 
2.25.1

[PATCH v3 1/8] fpga: altera-pr-ip: Remove function alt_pr_unregister

[Russ Weight]

Remove the alt_pr_unregister() function; it is no longer used.

Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Xu Yilun <yilun.xu@intel.com>
---
v3:
  - Added Reviewed-by tag
v2:
  - The first version of this patch was entitled:
    "fpga: altera-pr-ip: Remove function alt_pr_unregister". This version of the
    patch removes the alt_pr_unregister() function altogether, instead of just
    removing portions of it.
---
 drivers/fpga/altera-pr-ip-core.c       | 10 ----------
 include/linux/fpga/altera-pr-ip-core.h |  1 -
 2 files changed, 11 deletions(-)

diff --git a/drivers/fpga/altera-pr-ip-core.c b/drivers/fpga/altera-pr-ip-core.c
index 5b130c4d9882..dfdf21ed34c4 100644
--- a/drivers/fpga/altera-pr-ip-core.c
+++ b/drivers/fpga/altera-pr-ip-core.c
@@ -199,16 +199,6 @@ int alt_pr_register(struct device *dev, void __iomem *reg_base)
 }
 EXPORT_SYMBOL_GPL(alt_pr_register);
 
-void alt_pr_unregister(struct device *dev)
-{
-	struct fpga_manager *mgr = dev_get_drvdata(dev);
-
-	dev_dbg(dev, "%s\n", __func__);
-
-	fpga_mgr_unregister(mgr);
-}
-EXPORT_SYMBOL_GPL(alt_pr_unregister);
-
 MODULE_AUTHOR("Matthew Gerlach <matthew.gerlach@linux.intel.com>");
 MODULE_DESCRIPTION("Altera Partial Reconfiguration IP Core");
 MODULE_LICENSE("GPL v2");
diff --git a/include/linux/fpga/altera-pr-ip-core.h b/include/linux/fpga/altera-pr-ip-core.h
index 0b08ac20ab16..a6b4c07858cc 100644
--- a/include/linux/fpga/altera-pr-ip-core.h
+++ b/include/linux/fpga/altera-pr-ip-core.h
@@ -13,6 +13,5 @@
 #include <linux/io.h>
 
 int alt_pr_register(struct device *dev, void __iomem *reg_base);
-void alt_pr_unregister(struct device *dev);
 
 #endif /* _ALT_PR_IP_CORE_H */
-- 
2.25.1

[PATCH v3 2/8] fpga: stratix10-soc: Add missing fpga_mgr_free() call

[Russ Weight]

The stratix10-soc driver uses fpga_mgr_create() function and is therefore
responsible to call fpga_mgr_free() to release the class driver resources.
Add a missing call to fpga_mgr_free in the s10_remove() function.

Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Xu Yilun <yilun.xu@intel.com>
---
v3:
  - No change
v2:
  - Added reviewed-by tag
---
 drivers/fpga/stratix10-soc.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/fpga/stratix10-soc.c b/drivers/fpga/stratix10-soc.c
index 657a70c5fc99..9e34bbbce26e 100644
--- a/drivers/fpga/stratix10-soc.c
+++ b/drivers/fpga/stratix10-soc.c
@@ -454,6 +454,7 @@ static int s10_remove(struct platform_device *pdev)
 	struct s10_priv *priv = mgr->priv;
 
 	fpga_mgr_unregister(mgr);
+	fpga_mgr_free(mgr);
 	stratix10_svc_free_channel(priv->chan);
 
 	return 0;
-- 
2.25.1

[PATCH v3 3/8] fpga: mgr: Rename dev to parent for parent device

[Russ Weight]

Rename variable "dev" to "parent" in cases where it represents the parent
device.

Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Xu Yilun <yilun.xu@intel.com>
---
v3:
  - Added Reviewed-by tag
v2:
  - This patch contains the renaming of "dev" to "parent" that was previously
    part of the patch: "fpga: mgr: Use standard dev_release for class driver"
---
 drivers/fpga/fpga-mgr.c | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
index b85bc47c91a9..42ddc0844781 100644
--- a/drivers/fpga/fpga-mgr.c
+++ b/drivers/fpga/fpga-mgr.c
@@ -551,7 +551,7 @@ EXPORT_SYMBOL_GPL(fpga_mgr_unlock);
 
 /**
  * fpga_mgr_create - create and initialize a FPGA manager struct
- * @dev:	fpga manager device from pdev
+ * @parent:	fpga manager device from pdev
  * @name:	fpga manager name
  * @mops:	pointer to structure of fpga manager ops
  * @priv:	fpga manager private data
@@ -561,7 +561,7 @@ EXPORT_SYMBOL_GPL(fpga_mgr_unlock);
  *
  * Return: pointer to struct fpga_manager or NULL
  */
-struct fpga_manager *fpga_mgr_create(struct device *dev, const char *name,
+struct fpga_manager *fpga_mgr_create(struct device *parent, const char *name,
 				     const struct fpga_manager_ops *mops,
 				     void *priv)
 {
@@ -571,12 +571,12 @@ struct fpga_manager *fpga_mgr_create(struct device *dev, const char *name,
 	if (!mops || !mops->write_complete || !mops->state ||
 	    !mops->write_init || (!mops->write && !mops->write_sg) ||
 	    (mops->write && mops->write_sg)) {
-		dev_err(dev, "Attempt to register without fpga_manager_ops\n");
+		dev_err(parent, "Attempt to register without fpga_manager_ops\n");
 		return NULL;
 	}
 
 	if (!name || !strlen(name)) {
-		dev_err(dev, "Attempt to register with no name!\n");
+		dev_err(parent, "Attempt to register with no name!\n");
 		return NULL;
 	}
 
@@ -597,8 +597,8 @@ struct fpga_manager *fpga_mgr_create(struct device *dev, const char *name,
 	device_initialize(&mgr->dev);
 	mgr->dev.class = fpga_mgr_class;
 	mgr->dev.groups = mops->groups;
-	mgr->dev.parent = dev;
-	mgr->dev.of_node = dev->of_node;
+	mgr->dev.parent = parent;
+	mgr->dev.of_node = parent->of_node;
 	mgr->dev.id = id;
 
 	ret = dev_set_name(&mgr->dev, "fpga%d", id);
@@ -636,7 +636,7 @@ static void devm_fpga_mgr_release(struct device *dev, void *res)
 
 /**
  * devm_fpga_mgr_create - create and initialize a managed FPGA manager struct
- * @dev:	fpga manager device from pdev
+ * @parent:	fpga manager device from pdev
  * @name:	fpga manager name
  * @mops:	pointer to structure of fpga manager ops
  * @priv:	fpga manager private data
@@ -651,7 +651,7 @@ static void devm_fpga_mgr_release(struct device *dev, void *res)
  *
  * Return: pointer to struct fpga_manager or NULL
  */
-struct fpga_manager *devm_fpga_mgr_create(struct device *dev, const char *name,
+struct fpga_manager *devm_fpga_mgr_create(struct device *parent, const char *name,
 					  const struct fpga_manager_ops *mops,
 					  void *priv)
 {
@@ -661,13 +661,13 @@ struct fpga_manager *devm_fpga_mgr_create(struct device *dev, const char *name,
 	if (!dr)
 		return NULL;
 
-	dr->mgr = fpga_mgr_create(dev, name, mops, priv);
+	dr->mgr = fpga_mgr_create(parent, name, mops, priv);
 	if (!dr->mgr) {
 		devres_free(dr);
 		return NULL;
 	}
 
-	devres_add(dev, dr);
+	devres_add(parent, dr);
 
 	return dr->mgr;
 }
-- 
2.25.1

[PATCH v3 4/8] fpga: bridge: Rename dev to parent for parent device

[Russ Weight]

Rename variable "dev" to "parent" in cases where it represents the parent
device.

Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Xu Yilun <yilun.xu@intel.com>
---
v3:
  - Added Reviewed-by tag
v2:
  - This patch contains the renaming of "dev" to "parent" that was previously
    part of the patch: "fpga: bridge: Use standard dev_release for class driver"
---
 drivers/fpga/fpga-bridge.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/fpga/fpga-bridge.c b/drivers/fpga/fpga-bridge.c
index 05c6d4f2d043..6c56afc66a6d 100644
--- a/drivers/fpga/fpga-bridge.c
+++ b/drivers/fpga/fpga-bridge.c
@@ -313,7 +313,7 @@ ATTRIBUTE_GROUPS(fpga_bridge);
 
 /**
  * fpga_bridge_create - create and initialize a struct fpga_bridge
- * @dev:	FPGA bridge device from pdev
+ * @parent:	FPGA bridge device from pdev
  * @name:	FPGA bridge name
  * @br_ops:	pointer to structure of fpga bridge ops
  * @priv:	FPGA bridge private data
@@ -323,7 +323,7 @@ ATTRIBUTE_GROUPS(fpga_bridge);
  *
  * Return: struct fpga_bridge or NULL
  */
-struct fpga_bridge *fpga_bridge_create(struct device *dev, const char *name,
+struct fpga_bridge *fpga_bridge_create(struct device *parent, const char *name,
 				       const struct fpga_bridge_ops *br_ops,
 				       void *priv)
 {
@@ -331,7 +331,7 @@ struct fpga_bridge *fpga_bridge_create(struct device *dev, const char *name,
 	int id, ret;
 
 	if (!name || !strlen(name)) {
-		dev_err(dev, "Attempt to register with no name!\n");
+		dev_err(parent, "Attempt to register with no name!\n");
 		return NULL;
 	}
 
@@ -353,8 +353,8 @@ struct fpga_bridge *fpga_bridge_create(struct device *dev, const char *name,
 	device_initialize(&bridge->dev);
 	bridge->dev.groups = br_ops->groups;
 	bridge->dev.class = fpga_bridge_class;
-	bridge->dev.parent = dev;
-	bridge->dev.of_node = dev->of_node;
+	bridge->dev.parent = parent;
+	bridge->dev.of_node = parent->of_node;
 	bridge->dev.id = id;
 
 	ret = dev_set_name(&bridge->dev, "br%d", id);
@@ -392,7 +392,7 @@ static void devm_fpga_bridge_release(struct device *dev, void *res)
 
 /**
  * devm_fpga_bridge_create - create and init a managed struct fpga_bridge
- * @dev:	FPGA bridge device from pdev
+ * @parent:	FPGA bridge device from pdev
  * @name:	FPGA bridge name
  * @br_ops:	pointer to structure of fpga bridge ops
  * @priv:	FPGA bridge private data
@@ -408,7 +408,7 @@ static void devm_fpga_bridge_release(struct device *dev, void *res)
  *  Return: struct fpga_bridge or NULL
  */
 struct fpga_bridge
-*devm_fpga_bridge_create(struct device *dev, const char *name,
+*devm_fpga_bridge_create(struct device *parent, const char *name,
 			 const struct fpga_bridge_ops *br_ops, void *priv)
 {
 	struct fpga_bridge **ptr, *bridge;
@@ -417,12 +417,12 @@ struct fpga_bridge
 	if (!ptr)
 		return NULL;
 
-	bridge = fpga_bridge_create(dev, name, br_ops, priv);
+	bridge = fpga_bridge_create(parent, name, br_ops, priv);
 	if (!bridge) {
 		devres_free(ptr);
 	} else {
 		*ptr = bridge;
-		devres_add(dev, ptr);
+		devres_add(parent, ptr);
 	}
 
 	return bridge;
-- 
2.25.1

[PATCH v3 5/8] fpga: region: Rename dev to parent for parent device

[Russ Weight]

Rename variable "dev" to "parent" in cases where it represents the parent
device.

Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Xu Yilun <yilun.xu@intel.com>
---
v3:
  - Added a "dev" to "parent" rename in the comment header for
    devm_fpga_region_create() that was missed in the first verion.
  - Added Reviewed-by tag
v2:
  - This patch contains the renaming of "dev" to "parent" that was previously
    part of the patch: "fpga: region: Use standard dev_release for class driver"
---
 drivers/fpga/fpga-region.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index c3134b89c3fe..4d60d643cada 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -181,7 +181,7 @@ ATTRIBUTE_GROUPS(fpga_region);
 
 /**
  * fpga_region_create - alloc and init a struct fpga_region
- * @dev: device parent
+ * @parent: device parent
  * @mgr: manager that programs this region
  * @get_bridges: optional function to get bridges to a list
  *
@@ -192,7 +192,7 @@ ATTRIBUTE_GROUPS(fpga_region);
  * Return: struct fpga_region or NULL
  */
 struct fpga_region
-*fpga_region_create(struct device *dev,
+*fpga_region_create(struct device *parent,
 		    struct fpga_manager *mgr,
 		    int (*get_bridges)(struct fpga_region *))
 {
@@ -214,8 +214,8 @@ struct fpga_region
 
 	device_initialize(&region->dev);
 	region->dev.class = fpga_region_class;
-	region->dev.parent = dev;
-	region->dev.of_node = dev->of_node;
+	region->dev.parent = parent;
+	region->dev.of_node = parent->of_node;
 	region->dev.id = id;
 
 	ret = dev_set_name(&region->dev, "region%d", id);
@@ -253,7 +253,7 @@ static void devm_fpga_region_release(struct device *dev, void *res)
 
 /**
  * devm_fpga_region_create - create and initialize a managed FPGA region struct
- * @dev: device parent
+ * @parent: device parent
  * @mgr: manager that programs this region
  * @get_bridges: optional function to get bridges to a list
  *
@@ -268,7 +268,7 @@ static void devm_fpga_region_release(struct device *dev, void *res)
  * Return: struct fpga_region or NULL
  */
 struct fpga_region
-*devm_fpga_region_create(struct device *dev,
+*devm_fpga_region_create(struct device *parent,
 			 struct fpga_manager *mgr,
 			 int (*get_bridges)(struct fpga_region *))
 {
@@ -278,12 +278,12 @@ struct fpga_region
 	if (!ptr)
 		return NULL;
 
-	region = fpga_region_create(dev, mgr, get_bridges);
+	region = fpga_region_create(parent, mgr, get_bridges);
 	if (!region) {
 		devres_free(ptr);
 	} else {
 		*ptr = region;
-		devres_add(dev, ptr);
+		devres_add(parent, ptr);
 	}
 
 	return region;
-- 
2.25.1

[PATCH v3 6/8] fpga: mgr: Use standard dev_release for class driver

[Russ Weight]

The FPGA manager class driver data structure is being treated as a
managed resource instead of using the class.dev_release call-back
function to release the class data structure. This change populates
the class.dev_release function, changes the fpga_mgr_free() function
to call put_device() and changes the fpga_mgr_unregister() function
to call device_del() instead of device_unregister().

Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Xu Yilun <yilun.xu@intel.com>
---
v3:
  - Added Reviewed-by tag
v2:
  - Moved the renaming of "dev" to "parent" to a separate patch
  - Call fpga_mgr_free() in devm_fpga_mgr_release() instead of put_device()
---
 drivers/fpga/fpga-mgr.c | 35 +++++++++++++++--------------------
 1 file changed, 15 insertions(+), 20 deletions(-)

diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
index 42ddc0844781..9f6c3760b6ff 100644
--- a/drivers/fpga/fpga-mgr.c
+++ b/drivers/fpga/fpga-mgr.c
@@ -585,8 +585,10 @@ struct fpga_manager *fpga_mgr_create(struct device *parent, const char *name,
 		return NULL;
 
 	id = ida_simple_get(&fpga_mgr_ida, 0, 0, GFP_KERNEL);
-	if (id < 0)
-		goto error_kfree;
+	if (id < 0) {
+		kfree(mgr);
+		return NULL;
+	}
 
 	mutex_init(&mgr->ref_mutex);
 
@@ -602,17 +604,12 @@ struct fpga_manager *fpga_mgr_create(struct device *parent, const char *name,
 	mgr->dev.id = id;
 
 	ret = dev_set_name(&mgr->dev, "fpga%d", id);
-	if (ret)
-		goto error_device;
+	if (ret) {
+		put_device(&mgr->dev);
+		return NULL;
+	}
 
 	return mgr;
-
-error_device:
-	ida_simple_remove(&fpga_mgr_ida, id);
-error_kfree:
-	kfree(mgr);
-
-	return NULL;
 }
 EXPORT_SYMBOL_GPL(fpga_mgr_create);
 
@@ -622,8 +619,7 @@ EXPORT_SYMBOL_GPL(fpga_mgr_create);
  */
 void fpga_mgr_free(struct fpga_manager *mgr)
 {
-	ida_simple_remove(&fpga_mgr_ida, mgr->dev.id);
-	kfree(mgr);
+	put_device(&mgr->dev);
 }
 EXPORT_SYMBOL_GPL(fpga_mgr_free);
 
@@ -692,16 +688,11 @@ int fpga_mgr_register(struct fpga_manager *mgr)
 
 	ret = device_add(&mgr->dev);
 	if (ret)
-		goto error_device;
+		return ret;
 
 	dev_info(&mgr->dev, "%s registered\n", mgr->name);
 
 	return 0;
-
-error_device:
-	ida_simple_remove(&fpga_mgr_ida, mgr->dev.id);
-
-	return ret;
 }
 EXPORT_SYMBOL_GPL(fpga_mgr_register);
 
@@ -722,7 +713,7 @@ void fpga_mgr_unregister(struct fpga_manager *mgr)
 	if (mgr->mops->fpga_remove)
 		mgr->mops->fpga_remove(mgr);
 
-	device_unregister(&mgr->dev);
+	device_del(&mgr->dev);
 }
 EXPORT_SYMBOL_GPL(fpga_mgr_unregister);
 
@@ -781,6 +772,10 @@ 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)
-- 
2.25.1

[PATCH v3 7/8] fpga: bridge: Use standard dev_release for class driver

[Russ Weight]

The FPGA bridge class driver data structure is being treated as a managed
resource instead of using standard dev_release call-back to release the
class data structure. This change populates the class.dev_release function
and changes the fpga_bridge_free() function to call put_device(). It also
changes fpga_bridge_unregister() to call device_del() instead of
device_unregister().

Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Xu Yilun <yilun.xu@intel.com>
---
v3:
  - Added Reviewed-by tag
v2:
  - Moved the renaming of "dev" to "parent" to a separate patch
  - Call fpga_bridge_free() in devm_fpga_bridge_release() instead of
    put_device()
---
 drivers/fpga/fpga-bridge.c | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/drivers/fpga/fpga-bridge.c b/drivers/fpga/fpga-bridge.c
index 6c56afc66a6d..b40f4b4228e7 100644
--- a/drivers/fpga/fpga-bridge.c
+++ b/drivers/fpga/fpga-bridge.c
@@ -340,8 +340,10 @@ struct fpga_bridge *fpga_bridge_create(struct device *parent, const char *name,
 		return NULL;
 
 	id = ida_simple_get(&fpga_bridge_ida, 0, 0, GFP_KERNEL);
-	if (id < 0)
-		goto error_kfree;
+	if (id < 0) {
+		kfree(bridge);
+		return NULL;
+	}
 
 	mutex_init(&bridge->mutex);
 	INIT_LIST_HEAD(&bridge->node);
@@ -358,17 +360,12 @@ struct fpga_bridge *fpga_bridge_create(struct device *parent, const char *name,
 	bridge->dev.id = id;
 
 	ret = dev_set_name(&bridge->dev, "br%d", id);
-	if (ret)
-		goto error_device;
+	if (ret) {
+		put_device(&bridge->dev);
+		return NULL;
+	}
 
 	return bridge;
-
-error_device:
-	ida_simple_remove(&fpga_bridge_ida, id);
-error_kfree:
-	kfree(bridge);
-
-	return NULL;
 }
 EXPORT_SYMBOL_GPL(fpga_bridge_create);
 
@@ -378,8 +375,7 @@ EXPORT_SYMBOL_GPL(fpga_bridge_create);
  */
 void fpga_bridge_free(struct fpga_bridge *bridge)
 {
-	ida_simple_remove(&fpga_bridge_ida, bridge->dev.id);
-	kfree(bridge);
+	put_device(&bridge->dev);
 }
 EXPORT_SYMBOL_GPL(fpga_bridge_free);
 
@@ -469,12 +465,16 @@ void fpga_bridge_unregister(struct fpga_bridge *bridge)
 	if (bridge->br_ops && bridge->br_ops->fpga_bridge_remove)
 		bridge->br_ops->fpga_bridge_remove(bridge);
 
-	device_unregister(&bridge->dev);
+	device_del(&bridge->dev);
 }
 EXPORT_SYMBOL_GPL(fpga_bridge_unregister);
 
 static void fpga_bridge_dev_release(struct device *dev)
 {
+	struct fpga_bridge *bridge = to_fpga_bridge(dev);
+
+	ida_simple_remove(&fpga_bridge_ida, bridge->dev.id);
+	kfree(bridge);
 }
 
 static int __init fpga_bridge_dev_init(void)
-- 
2.25.1

[PATCH v3 8/8] fpga: region: Use standard dev_release for class driver

[Russ Weight]

The FPGA region class driver data structure is being treated as a managed
resource instead of using standard dev_release call-back to release the
class data structure. This change populates the class.dev_release function
and changes the fpga_region_free() function to call put_device().
It also changes fpga_region_unregister() to call device_del() instead
of device_unregister().

Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Reviewed-by: Xu Yilun <yilun.xu@intel.com>
---
v3:
  - moved a "dev" to "parent" rename in the comment header for
    devm_fpga_region_create() to the appropriate patch.
  - Added Reviewed-by tag
v2:
  - Moved the renaming of "dev" to "parent" to a separate patch
  - Call fpga_region_free() in devm_fpga_region_release() instead of put_device()
---
 drivers/fpga/fpga-region.c | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index 4d60d643cada..bdc15fab60c0 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -204,8 +204,10 @@ struct fpga_region
 		return NULL;
 
 	id = ida_simple_get(&fpga_region_ida, 0, 0, GFP_KERNEL);
-	if (id < 0)
-		goto err_free;
+	if (id < 0) {
+		kfree(region);
+		return NULL;
+	}
 
 	region->mgr = mgr;
 	region->get_bridges = get_bridges;
@@ -219,17 +221,12 @@ struct fpga_region
 	region->dev.id = id;
 
 	ret = dev_set_name(&region->dev, "region%d", id);
-	if (ret)
-		goto err_remove;
+	if (ret) {
+		put_device(&region->dev);
+		return NULL;
+	}
 
 	return region;
-
-err_remove:
-	ida_simple_remove(&fpga_region_ida, id);
-err_free:
-	kfree(region);
-
-	return NULL;
 }
 EXPORT_SYMBOL_GPL(fpga_region_create);
 
@@ -239,8 +236,7 @@ EXPORT_SYMBOL_GPL(fpga_region_create);
  */
 void fpga_region_free(struct fpga_region *region)
 {
-	ida_simple_remove(&fpga_region_ida, region->dev.id);
-	kfree(region);
+	put_device(&region->dev);
 }
 EXPORT_SYMBOL_GPL(fpga_region_free);
 
@@ -310,12 +306,16 @@ EXPORT_SYMBOL_GPL(fpga_region_register);
  */
 void fpga_region_unregister(struct fpga_region *region)
 {
-	device_unregister(&region->dev);
+	device_del(&region->dev);
 }
 EXPORT_SYMBOL_GPL(fpga_region_unregister);
 
 static void fpga_region_dev_release(struct device *dev)
 {
+	struct fpga_region *region = to_fpga_region(dev);
+
+	ida_simple_remove(&fpga_region_ida, region->dev.id);
+	kfree(region);
 }
 
 /**
-- 
2.25.1

Re: [PATCH v3 0/8] fpga: Populate dev_release functions

[Russ Weight]

I think this version of the patch is ready to go. If you agree, please
provide a Reviewed-by or Tested-by tag.

Thanks,
- Russ

On 6/10/21 12:34 PM, Russ Weight wrote:
> The FPGA framework has a convention of using managed resource functions
> to allow parent drivers to manage the data structures allocated by the
> class drivers. They use an empty *_dev_release() function to satisfy the
> class driver.
>
> This is inconsistent with linux driver model.
>
> These changes populate the class dev_release callback functions while
> maintaining the current API.  Additional changes are made to maintain
> consistency with the driver model.
>
> For more context on these changes, refer to this email thread:
>
> https://marc.info/?l=linux-fpga&m=162127412218557&w=2
>
> Changelog v2 -> v3:
>   - Added Reviewed-by tags
>   - Moved a "dev" to "parent" rename in the comment header for
>     devm_fpga_region_create() from patch 8 to patch 5.
>
> Changelog v1 -> v2:
>   - Moved the renaming of "dev" to "parent" into a separate patch each for
>     fpga-mgr, fpga-bridge, fpga-region.
>   - Restored the call to fpga_mgr_free() in devm_*_mgr_release() instead of 
>     changing it to put_device().
>   - Replaced patch "fpga: altera-pr-ip: Remove function alt_pr_unregister"
>     with "fpga: altera-pr-ip: Remove function alt_pr_unregister". This patch
>     removes the alt_pr_unregister() function altogether, instead of just
>     removing portions of it.
>
> Russ Weight (8):
>   fpga: altera-pr-ip: Remove function alt_pr_unregister
>   fpga: stratix10-soc: Add missing fpga_mgr_free() call
>   fpga: mgr: Rename dev to parent for parent device
>   fpga: bridge: Rename dev to parent for parent device
>   fpga: region: Rename dev to parent for parent device
>   fpga: mgr: Use standard dev_release for class driver
>   fpga: bridge: Use standard dev_release for class driver
>   fpga: region: Use standard dev_release for class driver
>
>  drivers/fpga/altera-pr-ip-core.c       | 10 -----
>  drivers/fpga/fpga-bridge.c             | 46 ++++++++++-----------
>  drivers/fpga/fpga-mgr.c                | 55 ++++++++++++--------------
>  drivers/fpga/fpga-region.c             | 44 ++++++++++-----------
>  drivers/fpga/stratix10-soc.c           |  1 +
>  include/linux/fpga/altera-pr-ip-core.h |  1 -
>  6 files changed, 71 insertions(+), 86 deletions(-)
>

Re: [PATCH v3 0/8] fpga: Populate dev_release functions

[Moritz Fischer]

On Thu, Jun 10, 2021 at 12:38:17PM -0700, Russ Weight wrote:
> I think this version of the patch is ready to go. If you agree, please
> provide a Reviewed-by or Tested-by tag.
> 
> Thanks,
> - Russ
> 
> On 6/10/21 12:34 PM, Russ Weight wrote:
> > The FPGA framework has a convention of using managed resource functions
> > to allow parent drivers to manage the data structures allocated by the
> > class drivers. They use an empty *_dev_release() function to satisfy the
> > class driver.
> >
> > This is inconsistent with linux driver model.
> >
> > These changes populate the class dev_release callback functions while
> > maintaining the current API.  Additional changes are made to maintain
> > consistency with the driver model.
> >
> > For more context on these changes, refer to this email thread:
> >
> > https://marc.info/?l=linux-fpga&m=162127412218557&w=2
> >
> > Changelog v2 -> v3:
> >   - Added Reviewed-by tags
> >   - Moved a "dev" to "parent" rename in the comment header for
> >     devm_fpga_region_create() from patch 8 to patch 5.
> >
> > Changelog v1 -> v2:
> >   - Moved the renaming of "dev" to "parent" into a separate patch each for
> >     fpga-mgr, fpga-bridge, fpga-region.
> >   - Restored the call to fpga_mgr_free() in devm_*_mgr_release() instead of 
> >     changing it to put_device().
> >   - Replaced patch "fpga: altera-pr-ip: Remove function alt_pr_unregister"
> >     with "fpga: altera-pr-ip: Remove function alt_pr_unregister". This patch
> >     removes the alt_pr_unregister() function altogether, instead of just
> >     removing portions of it.
> >
> > Russ Weight (8):
> >   fpga: altera-pr-ip: Remove function alt_pr_unregister
> >   fpga: stratix10-soc: Add missing fpga_mgr_free() call
> >   fpga: mgr: Rename dev to parent for parent device
> >   fpga: bridge: Rename dev to parent for parent device
> >   fpga: region: Rename dev to parent for parent device
> >   fpga: mgr: Use standard dev_release for class driver
> >   fpga: bridge: Use standard dev_release for class driver
> >   fpga: region: Use standard dev_release for class driver
> >
> >  drivers/fpga/altera-pr-ip-core.c       | 10 -----
> >  drivers/fpga/fpga-bridge.c             | 46 ++++++++++-----------
> >  drivers/fpga/fpga-mgr.c                | 55 ++++++++++++--------------
> >  drivers/fpga/fpga-region.c             | 44 ++++++++++-----------
> >  drivers/fpga/stratix10-soc.c           |  1 +
> >  include/linux/fpga/altera-pr-ip-core.h |  1 -
> >  6 files changed, 71 insertions(+), 86 deletions(-)
> >
> 

Series looks good to me now, I'll wait for others to chime in and pick
it up tomorrow if nobody speaks up.

Thanks for doing the work!

- Moritz