[PATCH v3 2/4] fpga: bridge: add devm_fpga_bridge_create
From: Alan Tull
Date: Wed Sep 26 2018 - 12:12:34 EST
Add devm_fpga_bridge_create() which is the managed
version of fpga_bridge_create().
Change current bridge drivers to use
devm_fpga_bridge_create().
Signed-off-by: Alan Tull <atull@xxxxxxxxxx>
Suggested-by: Federico Vaga <federico.vaga@xxxxxxx>
Acked-by: Moritz Fischer <mdf@xxxxxxxxxx>
---
v2: add suggested-by
v3: remove some unclear documentation about fpga_bridge_unregister
add Acked-by
---
Documentation/driver-api/fpga/fpga-bridge.rst | 3 ++
drivers/fpga/altera-fpga2sdram.c | 8 ++--
drivers/fpga/altera-freeze-bridge.c | 13 ++---
drivers/fpga/altera-hps2fpga.c | 7 ++-
drivers/fpga/dfl-fme-br.c | 11 ++---
drivers/fpga/fpga-bridge.c | 68 +++++++++++++++++++++++----
drivers/fpga/xilinx-pr-decoupler.c | 4 +-
include/linux/fpga/fpga-bridge.h | 4 ++
8 files changed, 80 insertions(+), 38 deletions(-)
diff --git a/Documentation/driver-api/fpga/fpga-bridge.rst b/Documentation/driver-api/fpga/fpga-bridge.rst
index 2c2aaca..ebbcbde 100644
--- a/Documentation/driver-api/fpga/fpga-bridge.rst
+++ b/Documentation/driver-api/fpga/fpga-bridge.rst
@@ -11,6 +11,9 @@ API to implement a new FPGA bridge
:functions: fpga_bridge_ops
.. kernel-doc:: drivers/fpga/fpga-bridge.c
+ :functions: devm_fpga_bridge_create
+
+.. kernel-doc:: drivers/fpga/fpga-bridge.c
:functions: fpga_bridge_create
.. kernel-doc:: drivers/fpga/fpga-bridge.c
diff --git a/drivers/fpga/altera-fpga2sdram.c b/drivers/fpga/altera-fpga2sdram.c
index 23660cc..a78e49c 100644
--- a/drivers/fpga/altera-fpga2sdram.c
+++ b/drivers/fpga/altera-fpga2sdram.c
@@ -121,18 +121,16 @@ static int alt_fpga_bridge_probe(struct platform_device *pdev)
/* Get f2s bridge configuration saved in handoff register */
regmap_read(sysmgr, SYSMGR_ISWGRP_HANDOFF3, &priv->mask);
- br = fpga_bridge_create(dev, F2S_BRIDGE_NAME,
- &altera_fpga2sdram_br_ops, priv);
+ br = devm_fpga_bridge_create(dev, F2S_BRIDGE_NAME,
+ &altera_fpga2sdram_br_ops, priv);
if (!br)
return -ENOMEM;
platform_set_drvdata(pdev, br);
ret = fpga_bridge_register(br);
- if (ret) {
- fpga_bridge_free(br);
+ if (ret)
return ret;
- }
dev_info(dev, "driver initialized with handoff %08x\n", priv->mask);
diff --git a/drivers/fpga/altera-freeze-bridge.c b/drivers/fpga/altera-freeze-bridge.c
index ffd586c..dd58c4a 100644
--- a/drivers/fpga/altera-freeze-bridge.c
+++ b/drivers/fpga/altera-freeze-bridge.c
@@ -213,7 +213,6 @@ static int altera_freeze_br_probe(struct platform_device *pdev)
struct fpga_bridge *br;
struct resource *res;
u32 status, revision;
- int ret;
if (!np)
return -ENODEV;
@@ -245,20 +244,14 @@ static int altera_freeze_br_probe(struct platform_device *pdev)
priv->base_addr = base_addr;
- br = fpga_bridge_create(dev, FREEZE_BRIDGE_NAME,
- &altera_freeze_br_br_ops, priv);
+ br = devm_fpga_bridge_create(dev, FREEZE_BRIDGE_NAME,
+ &altera_freeze_br_br_ops, priv);
if (!br)
return -ENOMEM;
platform_set_drvdata(pdev, br);
- ret = fpga_bridge_register(br);
- if (ret) {
- fpga_bridge_free(br);
- return ret;
- }
-
- return 0;
+ return fpga_bridge_register(br);
}
static int altera_freeze_br_remove(struct platform_device *pdev)
diff --git a/drivers/fpga/altera-hps2fpga.c b/drivers/fpga/altera-hps2fpga.c
index a974d3f..77b95f2 100644
--- a/drivers/fpga/altera-hps2fpga.c
+++ b/drivers/fpga/altera-hps2fpga.c
@@ -180,7 +180,8 @@ static int alt_fpga_bridge_probe(struct platform_device *pdev)
}
}
- br = fpga_bridge_create(dev, priv->name, &altera_hps2fpga_br_ops, priv);
+ br = devm_fpga_bridge_create(dev, priv->name,
+ &altera_hps2fpga_br_ops, priv);
if (!br) {
ret = -ENOMEM;
goto err;
@@ -190,12 +191,10 @@ static int alt_fpga_bridge_probe(struct platform_device *pdev)
ret = fpga_bridge_register(br);
if (ret)
- goto err_free;
+ goto err;
return 0;
-err_free:
- fpga_bridge_free(br);
err:
clk_disable_unprepare(priv->clk);
diff --git a/drivers/fpga/dfl-fme-br.c b/drivers/fpga/dfl-fme-br.c
index 7cc041d..3ff9f3a 100644
--- a/drivers/fpga/dfl-fme-br.c
+++ b/drivers/fpga/dfl-fme-br.c
@@ -61,7 +61,6 @@ static int fme_br_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct fme_br_priv *priv;
struct fpga_bridge *br;
- int ret;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
@@ -69,18 +68,14 @@ static int fme_br_probe(struct platform_device *pdev)
priv->pdata = dev_get_platdata(dev);
- br = fpga_bridge_create(dev, "DFL FPGA FME Bridge",
- &fme_bridge_ops, priv);
+ br = devm_fpga_bridge_create(dev, "DFL FPGA FME Bridge",
+ &fme_bridge_ops, priv);
if (!br)
return -ENOMEM;
platform_set_drvdata(pdev, br);
- ret = fpga_bridge_register(br);
- if (ret)
- fpga_bridge_free(br);
-
- return ret;
+ return fpga_bridge_register(br);
}
static int fme_br_remove(struct platform_device *pdev)
diff --git a/drivers/fpga/fpga-bridge.c b/drivers/fpga/fpga-bridge.c
index c983dac..80bd8f1 100644
--- a/drivers/fpga/fpga-bridge.c
+++ b/drivers/fpga/fpga-bridge.c
@@ -324,6 +324,9 @@ ATTRIBUTE_GROUPS(fpga_bridge);
* @br_ops: pointer to structure of fpga bridge ops
* @priv: FPGA bridge private data
*
+ * The caller of this function is responsible for freeing the bridge with
+ * fpga_bridge_free(). Using devm_fpga_bridge_create() instead is recommended.
+ *
* Return: struct fpga_bridge or NULL
*/
struct fpga_bridge *fpga_bridge_create(struct device *dev, const char *name,
@@ -378,8 +381,8 @@ struct fpga_bridge *fpga_bridge_create(struct device *dev, const char *name,
EXPORT_SYMBOL_GPL(fpga_bridge_create);
/**
- * fpga_bridge_free - free a fpga bridge and its id
- * @bridge: FPGA bridge struct created by fpga_bridge_create
+ * fpga_bridge_free - free a fpga bridge created by fpga_bridge_create()
+ * @bridge: FPGA bridge struct
*/
void fpga_bridge_free(struct fpga_bridge *bridge)
{
@@ -388,9 +391,56 @@ void fpga_bridge_free(struct fpga_bridge *bridge)
}
EXPORT_SYMBOL_GPL(fpga_bridge_free);
+static void devm_fpga_bridge_release(struct device *dev, void *res)
+{
+ struct fpga_bridge *bridge = *(struct fpga_bridge **)res;
+
+ fpga_bridge_free(bridge);
+}
+
/**
- * fpga_bridge_register - register a fpga bridge
- * @bridge: FPGA bridge struct created by fpga_bridge_create
+ * devm_fpga_bridge_create - create and init a managed struct fpga_bridge
+ * @dev: FPGA bridge device from pdev
+ * @name: FPGA bridge name
+ * @br_ops: pointer to structure of fpga bridge ops
+ * @priv: FPGA bridge private data
+ *
+ * This function is intended for use in a FPGA bridge driver's probe function.
+ * After the bridge driver creates the struct with devm_fpga_bridge_create(), it
+ * should register the bridge with fpga_bridge_register(). The bridge driver's
+ * remove function should call fpga_bridge_unregister(). The bridge 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_bridge_register(), the struct will still get cleaned up.
+ *
+ * Return: struct fpga_bridge or NULL
+ */
+struct fpga_bridge
+*devm_fpga_bridge_create(struct device *dev, const char *name,
+ const struct fpga_bridge_ops *br_ops, void *priv)
+{
+ struct fpga_bridge **ptr, *bridge;
+
+ ptr = devres_alloc(devm_fpga_bridge_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return NULL;
+
+ bridge = fpga_bridge_create(dev, name, br_ops, priv);
+ if (!bridge) {
+ devres_free(ptr);
+ } else {
+ *ptr = bridge;
+ devres_add(dev, ptr);
+ }
+
+ return bridge;
+}
+EXPORT_SYMBOL_GPL(devm_fpga_bridge_create);
+
+/**
+ * fpga_bridge_register - register a FPGA bridge
+ *
+ * @bridge: FPGA bridge struct
*
* Return: 0 for success, error code otherwise.
*/
@@ -412,8 +462,11 @@ int fpga_bridge_register(struct fpga_bridge *bridge)
EXPORT_SYMBOL_GPL(fpga_bridge_register);
/**
- * fpga_bridge_unregister - unregister and free a fpga bridge
- * @bridge: FPGA bridge struct created by fpga_bridge_create
+ * fpga_bridge_unregister - unregister a FPGA bridge
+ *
+ * @bridge: FPGA bridge struct
+ *
+ * This function is intended for use in a FPGA bridge driver's remove function.
*/
void fpga_bridge_unregister(struct fpga_bridge *bridge)
{
@@ -430,9 +483,6 @@ EXPORT_SYMBOL_GPL(fpga_bridge_unregister);
static void fpga_bridge_dev_release(struct device *dev)
{
- struct fpga_bridge *bridge = to_fpga_bridge(dev);
-
- fpga_bridge_free(bridge);
}
static int __init fpga_bridge_dev_init(void)
diff --git a/drivers/fpga/xilinx-pr-decoupler.c b/drivers/fpga/xilinx-pr-decoupler.c
index 07ba153..6410361 100644
--- a/drivers/fpga/xilinx-pr-decoupler.c
+++ b/drivers/fpga/xilinx-pr-decoupler.c
@@ -121,8 +121,8 @@ static int xlnx_pr_decoupler_probe(struct platform_device *pdev)
clk_disable(priv->clk);
- br = fpga_bridge_create(&pdev->dev, "Xilinx PR Decoupler",
- &xlnx_pr_decoupler_br_ops, priv);
+ br = devm_fpga_bridge_create(&pdev->dev, "Xilinx PR Decoupler",
+ &xlnx_pr_decoupler_br_ops, priv);
if (!br) {
err = -ENOMEM;
goto err_clk;
diff --git a/include/linux/fpga/fpga-bridge.h b/include/linux/fpga/fpga-bridge.h
index ce550fc..817600a 100644
--- a/include/linux/fpga/fpga-bridge.h
+++ b/include/linux/fpga/fpga-bridge.h
@@ -69,4 +69,8 @@ void fpga_bridge_free(struct fpga_bridge *br);
int fpga_bridge_register(struct fpga_bridge *br);
void fpga_bridge_unregister(struct fpga_bridge *br);
+struct fpga_bridge
+*devm_fpga_bridge_create(struct device *dev, const char *name,
+ const struct fpga_bridge_ops *br_ops, void *priv);
+
#endif /* _LINUX_FPGA_BRIDGE_H */
--
2.7.4