Re: [PATCH v3 1/3] fpga: mgr: Use standard dev_release for class driver

[Russ Weight <russell.h.weight@intel.com>]

Moritz,

On 5/24/21 4:07 PM, Russ Weight wrote:
>
> On 5/24/21 3:39 PM, Moritz Fischer wrote:
>> On Mon, May 24, 2021 at 11:50:47AM -0700, Russ Weight wrote:
>>> The FPGA manager 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 for the freeing of the class data structure
>>> and combines the create() and register() functions into a single
>>> register() function.
>>>
>>> The devm_fpga_mgr_register() function is retained.
>> Should this be maybe called devm_fpga_mgr_create_and_register() ?
> Yes - I think that is more descriptive. I'll make that change.

Before I make the change, consider this:

The core device_register() function is defined as:

> int device_register(struct device *dev)
> {
>         device_initialize(dev); # called by previous fpga-mgr-create()
>         return device_add(dev); # called by previous fpga_mgr_register()
> }
> EXPORT_SYMBOL_GPL(device_register);

In a sense, our prior naming convention was inconsistent with the driver
core, where the register() function encompasses both the both initialization
of the device and addition into the driver core.

It is true that we are allocating the data structure as well in the merged
registration function, but that could may be considered part of the
initialization step.

What do you think? Would it be OK to stick with the shorter name of
devm_fpga_mgr_register()?

- Russ

>
> - Russ
>
>>> Signed-off-by: Russ Weight <russell.h.weight@intel.com>
>>> ---
>>> v3:
>>>   - Cleaned up comment header for fpga_mgr_register()
>>>   - Fix error return on ida_simple_get() failure
>>> v2:
>>>   - Restored devm_fpga_mgr_register() functionality, adapted for the combined
>>>     create/register functionality.
>>>   - All previous callers of devm_fpga_mgr_register() will continue to call
>>>     devm_fpga_mgr_register().
>>>   - replaced unnecessary ternary operators in return statements with standard
>>>     if conditions.
>>> ---
>>>  drivers/fpga/altera-cvp.c        |  12 +--
>>>  drivers/fpga/altera-pr-ip-core.c |   8 +-
>>>  drivers/fpga/altera-ps-spi.c     |  10 +-
>>>  drivers/fpga/dfl-fme-mgr.c       |  10 +-
>>>  drivers/fpga/fpga-mgr.c          | 163 ++++++++-----------------------
>>>  drivers/fpga/ice40-spi.c         |  10 +-
>>>  drivers/fpga/machxo2-spi.c       |  10 +-
>>>  drivers/fpga/socfpga-a10.c       |  16 ++-
>>>  drivers/fpga/socfpga.c           |  10 +-
>>>  drivers/fpga/stratix10-soc.c     |  15 +--
>>>  drivers/fpga/ts73xx-fpga.c       |  10 +-
>>>  drivers/fpga/xilinx-spi.c        |  12 +--
>>>  drivers/fpga/zynq-fpga.c         |  16 ++-
>>>  drivers/fpga/zynqmp-fpga.c       |  10 +-
>>>  include/linux/fpga/fpga-mgr.h    |  17 ++--
>>>  15 files changed, 112 insertions(+), 217 deletions(-)
>>>
>>> diff --git a/drivers/fpga/altera-cvp.c b/drivers/fpga/altera-cvp.c
>>> index 4e0edb60bfba..b61020ceb0a1 100644
>>> --- a/drivers/fpga/altera-cvp.c
>>> +++ b/drivers/fpga/altera-cvp.c
>>> @@ -652,19 +652,15 @@ static int altera_cvp_probe(struct pci_dev *pdev,
>>>  	snprintf(conf->mgr_name, sizeof(conf->mgr_name), "%s @%s",
>>>  		 ALTERA_CVP_MGR_NAME, pci_name(pdev));
>>>  
>>> -	mgr = devm_fpga_mgr_create(&pdev->dev, conf->mgr_name,
>>> -				   &altera_cvp_ops, conf);
>>> -	if (!mgr) {
>>> -		ret = -ENOMEM;
>>> +	mgr = fpga_mgr_register(&pdev->dev, conf->mgr_name,
>>> +				&altera_cvp_ops, conf);
>>> +	if (IS_ERR(mgr)) {
>>> +		ret = PTR_ERR(mgr);
>>>  		goto err_unmap;
>>>  	}
>>>  
>>>  	pci_set_drvdata(pdev, mgr);
>>>  
>>> -	ret = fpga_mgr_register(mgr);
>>> -	if (ret)
>>> -		goto err_unmap;
>>> -
>>>  	return 0;
>>>  
>>>  err_unmap:
>>> diff --git a/drivers/fpga/altera-pr-ip-core.c b/drivers/fpga/altera-pr-ip-core.c
>>> index 5b130c4d9882..0980e134cc43 100644
>>> --- a/drivers/fpga/altera-pr-ip-core.c
>>> +++ b/drivers/fpga/altera-pr-ip-core.c
>>> @@ -191,11 +191,11 @@ int alt_pr_register(struct device *dev, void __iomem *reg_base)
>>>  		(val & ALT_PR_CSR_STATUS_MSK) >> ALT_PR_CSR_STATUS_SFT,
>>>  		(int)(val & ALT_PR_CSR_PR_START));
>>>  
>>> -	mgr = devm_fpga_mgr_create(dev, dev_name(dev), &alt_pr_ops, priv);
>>> -	if (!mgr)
>>> -		return -ENOMEM;
>>> +	mgr = devm_fpga_mgr_register(dev, dev_name(dev), &alt_pr_ops, priv);
>>> +	if (IS_ERR(mgr))
>>> +		return PTR_ERR(mgr);
>>>  
>>> -	return devm_fpga_mgr_register(dev, mgr);
>>> +	return 0;
>>>  }
>>>  EXPORT_SYMBOL_GPL(alt_pr_register);
>>>  
>>> diff --git a/drivers/fpga/altera-ps-spi.c b/drivers/fpga/altera-ps-spi.c
>>> index 23bfd4d1ad0f..d3f77b0312b2 100644
>>> --- a/drivers/fpga/altera-ps-spi.c
>>> +++ b/drivers/fpga/altera-ps-spi.c
>>> @@ -302,12 +302,12 @@ static int altera_ps_probe(struct spi_device *spi)
>>>  	snprintf(conf->mgr_name, sizeof(conf->mgr_name), "%s %s",
>>>  		 dev_driver_string(&spi->dev), dev_name(&spi->dev));
>>>  
>>> -	mgr = devm_fpga_mgr_create(&spi->dev, conf->mgr_name,
>>> -				   &altera_ps_ops, conf);
>>> -	if (!mgr)
>>> -		return -ENOMEM;
>>> +	mgr = devm_fpga_mgr_register(&spi->dev, conf->mgr_name,
>>> +				     &altera_ps_ops, conf);
>>> +	if (IS_ERR(mgr))
>>> +		return PTR_ERR(mgr);
>>>  
>>> -	return devm_fpga_mgr_register(&spi->dev, mgr);
>>> +	return 0;
>>>  }
>>>  
>>>  static const struct spi_device_id altera_ps_spi_ids[] = {
>>> diff --git a/drivers/fpga/dfl-fme-mgr.c b/drivers/fpga/dfl-fme-mgr.c
>>> index d5861d13b306..d71eba817b3b 100644
>>> --- a/drivers/fpga/dfl-fme-mgr.c
>>> +++ b/drivers/fpga/dfl-fme-mgr.c
>>> @@ -308,14 +308,14 @@ static int fme_mgr_probe(struct platform_device *pdev)
>>>  
>>>  	fme_mgr_get_compat_id(priv->ioaddr, compat_id);
>>>  
>>> -	mgr = devm_fpga_mgr_create(dev, "DFL FME FPGA Manager",
>>> -				   &fme_mgr_ops, priv);
>>> -	if (!mgr)
>>> -		return -ENOMEM;
>>> +	mgr = devm_fpga_mgr_register(dev, "DFL FME FPGA Manager",
>>> +				     &fme_mgr_ops, priv);
>>> +	if (IS_ERR(mgr))
>>> +		return PTR_ERR(mgr);
>>>  
>>>  	mgr->compat_id = compat_id;
>>>  
>>> -	return devm_fpga_mgr_register(dev, mgr);
>>> +	return 0;
>>>  }
>>>  
>>>  static struct platform_driver fme_mgr_driver = {
>>> diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
>>> index b85bc47c91a9..22f0dd5c2834 100644
>>> --- a/drivers/fpga/fpga-mgr.c
>>> +++ b/drivers/fpga/fpga-mgr.c
>>> @@ -550,20 +550,20 @@ void fpga_mgr_unlock(struct fpga_manager *mgr)
>>>  EXPORT_SYMBOL_GPL(fpga_mgr_unlock);
>>>  
>>>  /**
>>> - * fpga_mgr_create - create and initialize a FPGA manager struct
>>> + * fpga_mgr_register - create and register a FPGA Manager device
>>>   * @dev:	fpga manager device from pdev
>>>   * @name:	fpga manager name
>>>   * @mops:	pointer to structure of fpga manager ops
>>>   * @priv:	fpga manager private data
>>>   *
>>> - * 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 instead is recommended.
>>>   *
>>> - * Return: pointer to struct fpga_manager or NULL
>>> + * Returns a struct fpga_manager pointer on success, or ERR_PTR() on error.
>>>   */
>>> -struct fpga_manager *fpga_mgr_create(struct device *dev, const char *name,
>>> -				     const struct fpga_manager_ops *mops,
>>> -				     void *priv)
>>> +struct fpga_manager *
>>> +fpga_mgr_register(struct device *dev, const char *name,
>>> +		  const struct fpga_manager_ops *mops, void *priv)
>>>  {
>>>  	struct fpga_manager *mgr;
>>>  	int id, ret;
>>> @@ -572,21 +572,23 @@ struct fpga_manager *fpga_mgr_create(struct device *dev, const char *name,
>>>  	    !mops->write_init || (!mops->write && !mops->write_sg) ||
>>>  	    (mops->write && mops->write_sg)) {
>>>  		dev_err(dev, "Attempt to register without fpga_manager_ops\n");
>>> -		return NULL;
>>> +		return ERR_PTR(-EINVAL);
>>>  	}
>>>  
>>>  	if (!name || !strlen(name)) {
>>>  		dev_err(dev, "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);
>>>  
>>> @@ -594,7 +596,6 @@ struct fpga_manager *fpga_mgr_create(struct device *dev, const char *name,
>>>  	mgr->mops = mops;
>>>  	mgr->priv = priv;
>>>  
>>> -	device_initialize(&mgr->dev);
>>>  	mgr->dev.class = fpga_mgr_class;
>>>  	mgr->dev.groups = mops->groups;
>>>  	mgr->dev.parent = dev;
>>> @@ -605,84 +606,6 @@ struct fpga_manager *fpga_mgr_create(struct device *dev, const char *name,
>>>  	if (ret)
>>>  		goto error_device;
>>>  
>>> -	return mgr;
>>> -
>>> -error_device:
>>> -	ida_simple_remove(&fpga_mgr_ida, id);
>>> -error_kfree:
>>> -	kfree(mgr);
>>> -
>>> -	return NULL;
>>> -}
>>> -EXPORT_SYMBOL_GPL(fpga_mgr_create);
>>> -
>>> -/**
>>> - * fpga_mgr_free - free a 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
>>> - * @dev:	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 a 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.
>>> - *
>>> - * Return: pointer to struct fpga_manager or NULL
>>> - */
>>> -struct fpga_manager *devm_fpga_mgr_create(struct device *dev, const char *name,
>>> -					  const struct fpga_manager_ops *mops,
>>> -					  void *priv)
>>> -{
>>> -	struct fpga_mgr_devres *dr;
>>> -
>>> -	dr = devres_alloc(devm_fpga_mgr_release, sizeof(*dr), GFP_KERNEL);
>>> -	if (!dr)
>>> -		return NULL;
>>> -
>>> -	dr->mgr = fpga_mgr_create(dev, name, mops, priv);
>>> -	if (!dr->mgr) {
>>> -		devres_free(dr);
>>> -		return NULL;
>>> -	}
>>> -
>>> -	devres_add(dev, dr);
>>> -
>>> -	return dr->mgr;
>>> -}
>>> -EXPORT_SYMBOL_GPL(devm_fpga_mgr_create);
>>> -
>>> -/**
>>> - * fpga_mgr_register - register a 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
>>> @@ -690,18 +613,20 @@ int fpga_mgr_register(struct fpga_manager *mgr)
>>>  	 */
>>>  	mgr->state = mgr->mops->state(mgr);
>>>  
>>> -	ret = device_add(&mgr->dev);
>>> -	if (ret)
>>> -		goto error_device;
>>> -
>>> -	dev_info(&mgr->dev, "%s registered\n", mgr->name);
>>> +	ret = device_register(&mgr->dev);
>>> +	if (ret) {
>>> +		put_device(&mgr->dev);
>>> +		return ERR_PTR(ret);
>>> +	}
>>>  
>>> -	return 0;
>>> +	return mgr;
>>>  
>>>  error_device:
>>> -	ida_simple_remove(&fpga_mgr_ida, mgr->dev.id);
>>> +	ida_simple_remove(&fpga_mgr_ida, id);
>>> +error_kfree:
>>> +	kfree(mgr);
>>>  
>>> -	return ret;
>>> +	return ERR_PTR(ret);
>>>  }
>>>  EXPORT_SYMBOL_GPL(fpga_mgr_register);
>>>  
>>> @@ -726,14 +651,6 @@ 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;
>>> @@ -743,44 +660,44 @@ 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
>>> + * @dev:	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.
>>>   */
>>> -int devm_fpga_mgr_register(struct device *dev, struct fpga_manager *mgr)
>>> +struct fpga_manager *
>>> +devm_fpga_mgr_register(struct device *dev, const char *name,
>>> +		       const struct fpga_manager_ops *mops, void *priv)
>>>  {
>>>  	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(dev, name, mops, priv);
>>> +	if (IS_ERR(mgr)) {
>>>  		devres_free(dr);
>>> -		return ret;
>>> +		return mgr;
>>>  	}
>>>  
>>>  	dr->mgr = mgr;
>>>  	devres_add(dev, dr);
>>>  
>>> -	return 0;
>>> +	return mgr;
>>>  }
>>>  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)
>>> diff --git a/drivers/fpga/ice40-spi.c b/drivers/fpga/ice40-spi.c
>>> index 69dec5af23c3..91ac25f339f3 100644
>>> --- a/drivers/fpga/ice40-spi.c
>>> +++ b/drivers/fpga/ice40-spi.c
>>> @@ -178,12 +178,12 @@ static int ice40_fpga_probe(struct spi_device *spi)
>>>  		return ret;
>>>  	}
>>>  
>>> -	mgr = devm_fpga_mgr_create(dev, "Lattice iCE40 FPGA Manager",
>>> -				   &ice40_fpga_ops, priv);
>>> -	if (!mgr)
>>> -		return -ENOMEM;
>>> +	mgr = devm_fpga_mgr_register(dev, "Lattice iCE40 FPGA Manager",
>>> +				     &ice40_fpga_ops, priv);
>>> +	if (IS_ERR(mgr))
>>> +		return PTR_ERR(mgr);
>>>  
>>> -	return devm_fpga_mgr_register(dev, mgr);
>>> +	return 0;
>>>  }
>>>  
>>>  static const struct of_device_id ice40_fpga_of_match[] = {
>>> diff --git a/drivers/fpga/machxo2-spi.c b/drivers/fpga/machxo2-spi.c
>>> index 114a64d2b7a4..0137c1e2e706 100644
>>> --- a/drivers/fpga/machxo2-spi.c
>>> +++ b/drivers/fpga/machxo2-spi.c
>>> @@ -366,12 +366,12 @@ static int machxo2_spi_probe(struct spi_device *spi)
>>>  		return -EINVAL;
>>>  	}
>>>  
>>> -	mgr = devm_fpga_mgr_create(dev, "Lattice MachXO2 SPI FPGA Manager",
>>> -				   &machxo2_ops, spi);
>>> -	if (!mgr)
>>> -		return -ENOMEM;
>>> +	mgr = devm_fpga_mgr_register(dev, "Lattice MachXO2 SPI FPGA Manager",
>>> +				     &machxo2_ops, spi);
>>> +	if (IS_ERR(mgr))
>>> +		return PTR_ERR(mgr);
>>>  
>>> -	return devm_fpga_mgr_register(dev, mgr);
>>> +	return 0;
>>>  }
>>>  
>>>  static const struct of_device_id of_match[] = {
>>> diff --git a/drivers/fpga/socfpga-a10.c b/drivers/fpga/socfpga-a10.c
>>> index 573d88bdf730..ac8e89b8a5cc 100644
>>> --- a/drivers/fpga/socfpga-a10.c
>>> +++ b/drivers/fpga/socfpga-a10.c
>>> @@ -508,19 +508,15 @@ static int socfpga_a10_fpga_probe(struct platform_device *pdev)
>>>  		return -EBUSY;
>>>  	}
>>>  
>>> -	mgr = devm_fpga_mgr_create(dev, "SoCFPGA Arria10 FPGA Manager",
>>> -				   &socfpga_a10_fpga_mgr_ops, priv);
>>> -	if (!mgr)
>>> -		return -ENOMEM;
>>> -
>>> -	platform_set_drvdata(pdev, mgr);
>>> -
>>> -	ret = fpga_mgr_register(mgr);
>>> -	if (ret) {
>>> +	mgr = fpga_mgr_register(dev, "SoCFPGA Arria10 FPGA Manager",
>>> +				&socfpga_a10_fpga_mgr_ops, priv);
>>> +	if (IS_ERR(mgr)) {
>>>  		clk_disable_unprepare(priv->clk);
>>> -		return ret;
>>> +		return PTR_ERR(mgr);
>>>  	}
>>>  
>>> +	platform_set_drvdata(pdev, mgr);
>>> +
>>>  	return 0;
>>>  }
>>>  
>>> diff --git a/drivers/fpga/socfpga.c b/drivers/fpga/socfpga.c
>>> index 1f467173fc1f..ebfa9f4d24ef 100644
>>> --- a/drivers/fpga/socfpga.c
>>> +++ b/drivers/fpga/socfpga.c
>>> @@ -571,12 +571,12 @@ static int socfpga_fpga_probe(struct platform_device *pdev)
>>>  	if (ret)
>>>  		return ret;
>>>  
>>> -	mgr = devm_fpga_mgr_create(dev, "Altera SOCFPGA FPGA Manager",
>>> -				   &socfpga_fpga_ops, priv);
>>> -	if (!mgr)
>>> -		return -ENOMEM;
>>> +	mgr = devm_fpga_mgr_register(dev, "Altera SOCFPGA FPGA Manager",
>>> +				     &socfpga_fpga_ops, priv);
>>> +	if (IS_ERR(mgr))
>>> +		return PTR_ERR(mgr);
>>>  
>>> -	return devm_fpga_mgr_register(dev, mgr);
>>> +	return 0;
>>>  }
>>>  
>>>  #ifdef CONFIG_OF
>>> diff --git a/drivers/fpga/stratix10-soc.c b/drivers/fpga/stratix10-soc.c
>>> index 657a70c5fc99..e0bd91b3f7f8 100644
>>> --- a/drivers/fpga/stratix10-soc.c
>>> +++ b/drivers/fpga/stratix10-soc.c
>>> @@ -425,18 +425,11 @@ static int s10_probe(struct platform_device *pdev)
>>>  
>>>  	init_completion(&priv->status_return_completion);
>>>  
>>> -	mgr = fpga_mgr_create(dev, "Stratix10 SOC FPGA Manager",
>>> -			      &s10_ops, priv);
>>> -	if (!mgr) {
>>> -		dev_err(dev, "unable to create FPGA manager\n");
>>> -		ret = -ENOMEM;
>>> -		goto probe_err;
>>> -	}
>>> -
>>> -	ret = fpga_mgr_register(mgr);
>>> -	if (ret) {
>>> +	mgr = fpga_mgr_register(dev, "Stratix10 SOC FPGA Manager",
>>> +				&s10_ops, priv);
>>> +	if (IS_ERR(mgr)) {
>>>  		dev_err(dev, "unable to register FPGA manager\n");
>>> -		fpga_mgr_free(mgr);
>>> +		ret = PTR_ERR(mgr);
>>>  		goto probe_err;
>>>  	}
>>>  
>>> diff --git a/drivers/fpga/ts73xx-fpga.c b/drivers/fpga/ts73xx-fpga.c
>>> index 101f016c6ed8..5efbec2b9f9f 100644
>>> --- a/drivers/fpga/ts73xx-fpga.c
>>> +++ b/drivers/fpga/ts73xx-fpga.c
>>> @@ -122,12 +122,12 @@ static int ts73xx_fpga_probe(struct platform_device *pdev)
>>>  	if (IS_ERR(priv->io_base))
>>>  		return PTR_ERR(priv->io_base);
>>>  
>>> -	mgr = devm_fpga_mgr_create(kdev, "TS-73xx FPGA Manager",
>>> -				   &ts73xx_fpga_ops, priv);
>>> -	if (!mgr)
>>> -		return -ENOMEM;
>>> +	mgr = devm_fpga_mgr_register(kdev, "TS-73xx FPGA Manager",
>>> +				     &ts73xx_fpga_ops, priv);
>>> +	if (IS_ERR(mgr))
>>> +		return PTR_ERR(mgr);
>>>  
>>> -	return devm_fpga_mgr_register(kdev, mgr);
>>> +	return 0;
>>>  }
>>>  
>>>  static struct platform_driver ts73xx_fpga_driver = {
>>> diff --git a/drivers/fpga/xilinx-spi.c b/drivers/fpga/xilinx-spi.c
>>> index fee4d0abf6bf..efda475f7a98 100644
>>> --- a/drivers/fpga/xilinx-spi.c
>>> +++ b/drivers/fpga/xilinx-spi.c
>>> @@ -247,13 +247,13 @@ static int xilinx_spi_probe(struct spi_device *spi)
>>>  		return dev_err_probe(&spi->dev, PTR_ERR(conf->done),
>>>  				     "Failed to get DONE gpio\n");
>>>  
>>> -	mgr = devm_fpga_mgr_create(&spi->dev,
>>> -				   "Xilinx Slave Serial FPGA Manager",
>>> -				   &xilinx_spi_ops, conf);
>>> -	if (!mgr)
>>> -		return -ENOMEM;
>>> +	mgr = devm_fpga_mgr_register(&spi->dev,
>>> +				     "Xilinx Slave Serial FPGA Manager",
>>> +				     &xilinx_spi_ops, conf);
>>> +	if (IS_ERR(mgr))
>>> +		return PTR_ERR(mgr);
>>>  
>>> -	return devm_fpga_mgr_register(&spi->dev, mgr);
>>> +	return 0;
>>>  }
>>>  
>>>  static const struct of_device_id xlnx_spi_of_match[] = {
>>> diff --git a/drivers/fpga/zynq-fpga.c b/drivers/fpga/zynq-fpga.c
>>> index 07fa8d9ec675..74bbb9710f4e 100644
>>> --- a/drivers/fpga/zynq-fpga.c
>>> +++ b/drivers/fpga/zynq-fpga.c
>>> @@ -609,20 +609,16 @@ static int zynq_fpga_probe(struct platform_device *pdev)
>>>  
>>>  	clk_disable(priv->clk);
>>>  
>>> -	mgr = devm_fpga_mgr_create(dev, "Xilinx Zynq FPGA Manager",
>>> -				   &zynq_fpga_ops, priv);
>>> -	if (!mgr)
>>> -		return -ENOMEM;
>>> -
>>> -	platform_set_drvdata(pdev, mgr);
>>> -
>>> -	err = fpga_mgr_register(mgr);
>>> -	if (err) {
>>> +	mgr = fpga_mgr_register(dev, "Xilinx Zynq FPGA Manager",
>>> +				&zynq_fpga_ops, priv);
>>> +	if (IS_ERR(mgr)) {
>>>  		dev_err(dev, "unable to register FPGA manager\n");
>>>  		clk_unprepare(priv->clk);
>>> -		return err;
>>> +		return PTR_ERR(mgr);
>>>  	}
>>>  
>>> +	platform_set_drvdata(pdev, mgr);
>>> +
>>>  	return 0;
>>>  }
>>>  
>>> diff --git a/drivers/fpga/zynqmp-fpga.c b/drivers/fpga/zynqmp-fpga.c
>>> index 125743c9797f..1a6d520985be 100644
>>> --- a/drivers/fpga/zynqmp-fpga.c
>>> +++ b/drivers/fpga/zynqmp-fpga.c
>>> @@ -102,12 +102,12 @@ static int zynqmp_fpga_probe(struct platform_device *pdev)
>>>  
>>>  	priv->dev = dev;
>>>  
>>> -	mgr = devm_fpga_mgr_create(dev, "Xilinx ZynqMP FPGA Manager",
>>> -				   &zynqmp_fpga_ops, priv);
>>> -	if (!mgr)
>>> -		return -ENOMEM;
>>> +	mgr = devm_fpga_mgr_register(dev, "Xilinx ZynqMP FPGA Manager",
>>> +				     &zynqmp_fpga_ops, priv);
>>> +	if (IS_ERR(mgr))
>>> +		return PTR_ERR(mgr);
>>>  
>>> -	return devm_fpga_mgr_register(dev, mgr);
>>> +	return 0;
>>>  }
>>>  
>>>  static const struct of_device_id zynqmp_fpga_of_match[] = {
>>> diff --git a/include/linux/fpga/fpga-mgr.h b/include/linux/fpga/fpga-mgr.h
>>> index 2bc3030a69e5..d1ccf8f8c38a 100644
>>> --- a/include/linux/fpga/fpga-mgr.h
>>> +++ b/include/linux/fpga/fpga-mgr.h
>>> @@ -191,17 +191,14 @@ struct fpga_manager *fpga_mgr_get(struct device *dev);
>>>  
>>>  void fpga_mgr_put(struct fpga_manager *mgr);
>>>  
>>> -struct fpga_manager *fpga_mgr_create(struct device *dev, const char *name,
>>> -				     const struct fpga_manager_ops *mops,
>>> -				     void *priv);
>>> -void fpga_mgr_free(struct fpga_manager *mgr);
>>> -int fpga_mgr_register(struct fpga_manager *mgr);
>>> +struct fpga_manager *fpga_mgr_register(struct device *dev, const char *name,
>>> +				       const struct fpga_manager_ops *mops,
>>> +				       void *priv);
>>>  void fpga_mgr_unregister(struct fpga_manager *mgr);
>>>  
>>> -int devm_fpga_mgr_register(struct device *dev, struct fpga_manager *mgr);
>>> -
>>> -struct fpga_manager *devm_fpga_mgr_create(struct device *dev, const char *name,
>>> -					  const struct fpga_manager_ops *mops,
>>> -					  void *priv);
>>> +struct fpga_manager *
>>> +devm_fpga_mgr_register(struct device *dev, const char *name,
>>> +		       const struct fpga_manager_ops *mops,
>>> +		       void *priv);
>>>  
>>>  #endif /*_LINUX_FPGA_MGR_H */
>>> -- 
>>> 2.25.1
>>>
>> Moritz