[PATCH v1 3/3] fpga: region: Use standard dev_release for class driver

From: Russ Weight
Date: Thu May 20 2021 - 21:04:24 EST

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 removes the
managed resource code and combines the create() and register()
functions into a single register() function.

Signed-off-by: Russ Weight <russell.h.weight@xxxxxxxxx>
---
drivers/fpga/dfl-fme-region.c | 10 +---
drivers/fpga/dfl.c | 10 +---
drivers/fpga/fpga-region.c | 97 ++++++--------------------------
drivers/fpga/of-fpga-region.c | 10 +---
include/linux/fpga/fpga-region.h | 12 +---
5 files changed, 28 insertions(+), 111 deletions(-)

diff --git a/drivers/fpga/dfl-fme-region.c b/drivers/fpga/dfl-fme-region.c
index 1eeb42af1012..631c8ce160e3 100644
--- a/drivers/fpga/dfl-fme-region.c
+++ b/drivers/fpga/dfl-fme-region.c
@@ -39,9 +39,9 @@ static int fme_region_probe(struct platform_device *pdev)
if (IS_ERR(mgr))
return -EPROBE_DEFER;

- region = devm_fpga_region_create(dev, mgr, fme_region_get_bridges);
- if (!region) {
- ret = -ENOMEM;
+ region = fpga_region_register(dev, mgr, fme_region_get_bridges);
+ if (IS_ERR(region)) {
+ ret = PTR_ERR(region);
goto eprobe_mgr_put;
}

@@ -49,10 +49,6 @@ static int fme_region_probe(struct platform_device *pdev)
region->compat_id = mgr->compat_id;
platform_set_drvdata(pdev, region);

- ret = fpga_region_register(region);
- if (ret)
- goto eprobe_mgr_put;
-
dev_dbg(dev, "DFL FME FPGA Region probed\n");

return 0;
diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c
index 511b20ff35a3..2fb3a5bfe4df 100644
--- a/drivers/fpga/dfl.c
+++ b/drivers/fpga/dfl.c
@@ -1400,9 +1400,9 @@ dfl_fpga_feature_devs_enumerate(struct dfl_fpga_enum_info *info)
if (!cdev)
return ERR_PTR(-ENOMEM);

- cdev->region = devm_fpga_region_create(info->dev, NULL, NULL);
- if (!cdev->region) {
- ret = -ENOMEM;
+ cdev->region = fpga_region_register(info->dev, NULL, NULL);
+ if (IS_ERR(cdev->region)) {
+ ret = PTR_ERR(cdev->region);
goto free_cdev_exit;
}

@@ -1410,10 +1410,6 @@ dfl_fpga_feature_devs_enumerate(struct dfl_fpga_enum_info *info)
mutex_init(&cdev->lock);
INIT_LIST_HEAD(&cdev->port_dev_list);

- ret = fpga_region_register(cdev->region);
- if (ret)
- goto free_cdev_exit;
-
/* create and init build info for enumeration */
binfo = devm_kzalloc(info->dev, sizeof(*binfo), GFP_KERNEL);
if (!binfo) {
diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index c3134b89c3fe..622b9d598758 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -185,23 +185,18 @@ ATTRIBUTE_GROUPS(fpga_region);
* @mgr: manager that programs this region
* @get_bridges: optional function to get bridges to a list
*
- * The caller of this function is responsible for freeing the resulting region
- * struct with fpga_region_free(). Using devm_fpga_region_create() instead is
- * recommended.
- *
- * Return: struct fpga_region or NULL
+ * Returns a struct fpga_region pointer on success, or ERR_PTR() on error.
*/
-struct fpga_region
-*fpga_region_create(struct device *dev,
- struct fpga_manager *mgr,
- int (*get_bridges)(struct fpga_region *))
+struct fpga_region *
+fpga_region_register(struct device *dev, struct fpga_manager *mgr,
+ int (*get_bridges)(struct fpga_region *))
{
struct fpga_region *region;
int id, ret = 0;

region = kzalloc(sizeof(*region), GFP_KERNEL);
if (!region)
- return NULL;
+ return ERR_PTR(-ENOMEM);

id = ida_simple_get(&fpga_region_ida, 0, 0, GFP_KERNEL);
if (id < 0)
@@ -212,7 +207,6 @@ struct fpga_region
mutex_init(&region->mutex);
INIT_LIST_HEAD(&region->bridge_list);

- device_initialize(&region->dev);
region->dev.class = fpga_region_class;
region->dev.parent = dev;
region->dev.of_node = dev->of_node;
@@ -222,6 +216,12 @@ struct fpga_region
if (ret)
goto err_remove;

+ ret = device_register(&region->dev);
+ if (ret) {
+ put_device(&region->dev);
+ return ERR_PTR(ret);
+ }
+
return region;

err_remove:
@@ -229,76 +229,7 @@ struct fpga_region
err_free:
kfree(region);

- return NULL;
-}
-EXPORT_SYMBOL_GPL(fpga_region_create);
-
-/**
- * fpga_region_free - free a FPGA region created by fpga_region_create()
- * @region: FPGA region
- */
-void fpga_region_free(struct fpga_region *region)
-{
- ida_simple_remove(&fpga_region_ida, region->dev.id);
- kfree(region);
-}
-EXPORT_SYMBOL_GPL(fpga_region_free);
-
-static void devm_fpga_region_release(struct device *dev, void *res)
-{
- struct fpga_region *region = *(struct fpga_region **)res;
-
- fpga_region_free(region);
-}
-
-/**
- * devm_fpga_region_create - create and initialize a managed FPGA region struct
- * @dev: device parent
- * @mgr: manager that programs this region
- * @get_bridges: optional function to get bridges to a list
- *
- * This function is intended for use in a FPGA region driver's probe function.
- * After the region driver creates the region struct with
- * devm_fpga_region_create(), it should register it with fpga_region_register().
- * The region driver's remove function should call fpga_region_unregister().
- * The region 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_region_register(), the struct will still get cleaned up.
- *
- * Return: struct fpga_region or NULL
- */
-struct fpga_region
-*devm_fpga_region_create(struct device *dev,
- struct fpga_manager *mgr,
- int (*get_bridges)(struct fpga_region *))
-{
- struct fpga_region **ptr, *region;
-
- ptr = devres_alloc(devm_fpga_region_release, sizeof(*ptr), GFP_KERNEL);
- if (!ptr)
- return NULL;
-
- region = fpga_region_create(dev, mgr, get_bridges);
- if (!region) {
- devres_free(ptr);
- } else {
- *ptr = region;
- devres_add(dev, ptr);
- }
-
- return region;
-}
-EXPORT_SYMBOL_GPL(devm_fpga_region_create);
-
-/**
- * fpga_region_register - register a FPGA region
- * @region: FPGA region
- *
- * Return: 0 or -errno
- */
-int fpga_region_register(struct fpga_region *region)
-{
- return device_add(&region->dev);
+ return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(fpga_region_register);

@@ -316,6 +247,10 @@ 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);
}

/**
diff --git a/drivers/fpga/of-fpga-region.c b/drivers/fpga/of-fpga-region.c
index e405309baadc..466e083654ae 100644
--- a/drivers/fpga/of-fpga-region.c
+++ b/drivers/fpga/of-fpga-region.c
@@ -405,16 +405,12 @@ static int of_fpga_region_probe(struct platform_device *pdev)
if (IS_ERR(mgr))
return -EPROBE_DEFER;

- region = devm_fpga_region_create(dev, mgr, of_fpga_region_get_bridges);
- if (!region) {
- ret = -ENOMEM;
+ region = fpga_region_register(dev, mgr, of_fpga_region_get_bridges);
+ if (IS_ERR(region)) {
+ ret = PTR_ERR(region);
goto eprobe_mgr_put;
}

- ret = fpga_region_register(region);
- if (ret)
- goto eprobe_mgr_put;
-
of_platform_populate(np, fpga_region_of_match, NULL, &region->dev);
platform_set_drvdata(pdev, region);

diff --git a/include/linux/fpga/fpga-region.h b/include/linux/fpga/fpga-region.h
index 27cb706275db..ca793f43af14 100644
--- a/include/linux/fpga/fpga-region.h
+++ b/include/linux/fpga/fpga-region.h
@@ -37,15 +37,9 @@ struct fpga_region *fpga_region_class_find(

int fpga_region_program_fpga(struct fpga_region *region);

-struct fpga_region
-*fpga_region_create(struct device *dev, struct fpga_manager *mgr,
- int (*get_bridges)(struct fpga_region *));
-void fpga_region_free(struct fpga_region *region);
-int fpga_region_register(struct fpga_region *region);
+struct fpga_region *
+fpga_region_register(struct device *dev, struct fpga_manager *mgr,
+ int (*get_bridges)(struct fpga_region *));
void fpga_region_unregister(struct fpga_region *region);

-struct fpga_region
-*devm_fpga_region_create(struct device *dev, struct fpga_manager *mgr,
- int (*get_bridges)(struct fpga_region *));
-
#endif /* _FPGA_REGION_H */
--
2.25.1