Re: [PATCH v5 1/3] fpga: mgr: Use standard dev_release for class driver

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

On 6/18/21 1:39 PM, Tom Rix wrote:
>
> On 6/18/21 10:58 AM, Russ Weight wrote:
>>
>> On 6/18/21 9:03 AM, Russ Weight wrote:
>>> On 6/18/21 8:45 AM, Xu Yilun wrote:
>>>> On Wed, Jun 16, 2021 at 03:57:38PM -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.
>>>>>
>>>>> Signed-off-by: Russ Weight <russell.h.weight@intel.com>
>>>>> ---
>>>>> v5:
>>>>>    - Rebased on top of recently accepted patches.
>>>>>    - Removed compat_id from the fpga_mgr_register() parameter list
>>>>>      and added it to the fpga_manager_ops structure. This also required
>>>> My reason for this change is, we could avoid further change of the
>>>> fpga_mgr_register() API if we add new input parameters later on.
>>> With this patchset, changes are only required for the callers
>>> that use the new parameters.
>>>
>>>>>      dynamically allocating the dfl-fme-ops structure in order to add
>>>>>      the appropriate compat_id.
>>>> But enforcing the dynamical allocation of the parameters is not prefered
>>>> to me. How about a dedicated structure that wraps all the needed
>>>> parameters:
>>>>
>>>> struct fpga_mgr_info {
>>>>     const char *name;
>>>>     const struct fpga_manager_ops *mops;
>>>>     const struct fpga_compat_id *compat_id;
>>>>     const void *priv;
>>>> };
>>>>
>>>> Then We can simply define a local variable of this struct for
>>>> fpga_mgr_register().
>>>>
>>>> more details inline.
>>> I agree the at the dynamic allocation is not preferred, but it is only
>>> required if compat_id is used. In all other cases, the static structure
>>> can continue to be used. In otherwords, only one caller is affected.
>>>>> v4:
>>>>>    - Added the compat_id parameter to fpga_mgr_register() and
>>>>>      devm_fpga_mgr_register() to ensure that the compat_id is set before
>>>>>      the device_register() call.
>>>>> 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       |  52 ++++++----
>>>>>   drivers/fpga/dfl-fme-region.c    |   2 +-
>>>>>   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     |  16 +--
>>>>>   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    |  43 ++++----
>>>>>   16 files changed, 153 insertions(+), 247 deletions(-)
>>>>>
>>>>> diff --git a/drivers/fpga/altera-cvp.c b/drivers/fpga/altera-cvp.c
>>>>> index ccf4546eff29..4ffb9da537d8 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 dfdf21ed34c4..17babf974852 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..1b93bc292dbe 100644
>>>>> --- a/drivers/fpga/dfl-fme-mgr.c
>>>>> +++ b/drivers/fpga/dfl-fme-mgr.c
>>>>> @@ -264,14 +264,6 @@ static u64 fme_mgr_status(struct fpga_manager *mgr)
>>>>>       return pr_error_to_mgr_status(priv->pr_error);
>>>>>   }
>>>>>   -static const struct fpga_manager_ops fme_mgr_ops = {
>>>>> -    .write_init = fme_mgr_write_init,
>>>>> -    .write = fme_mgr_write,
>>>>> -    .write_complete = fme_mgr_write_complete,
>>>>> -    .state = fme_mgr_state,
>>>>> -    .status = fme_mgr_status,
>>>>> -};
>>>>> -
>>>>>   static void fme_mgr_get_compat_id(void __iomem *fme_pr,
>>>>>                     struct fpga_compat_id *id)
>>>>>   {
>>>>> @@ -279,10 +271,34 @@ static void fme_mgr_get_compat_id(void __iomem *fme_pr,
>>>>>       id->id_h = readq(fme_pr + FME_PR_INTFC_ID_H);
>>>>>   }
>>>>>   +static struct fpga_manager_ops *fme_mgr_get_ops(struct device *dev,
>>>>> +                        struct fme_mgr_priv *priv)
>>>>> +{
>>>>> +    struct fpga_manager_ops *ops;
>>>>> +
>>>>> +    ops = devm_kzalloc(dev, sizeof(*ops), GFP_KERNEL);
>>>>> +    if (!ops)
>>>>> +        return NULL;
>>>>> +
>>>>> +    ops->compat_id = devm_kzalloc(dev, sizeof(struct fpga_compat_id),
>>>>> +                      GFP_KERNEL);
>>>>> +    if (!ops->compat_id)
>>>>> +        return NULL;
>>>>> +
>>>>> +    fme_mgr_get_compat_id(priv->ioaddr, ops->compat_id);
>>>>> +    ops->write_init = fme_mgr_write_init;
>>>>> +    ops->write = fme_mgr_write;
>>>>> +    ops->write_complete = fme_mgr_write_complete;
>>>>> +    ops->state = fme_mgr_state;
>>>>> +    ops->status = fme_mgr_status;
>>>>> +
>>>>> +    return ops;
>>>>> +}
>> What do other's think? Is it better to dynamically allocate the ops structure
>> for users of compat_id (just one user at this time)? Or better to create an
>> info structure on the stack for all callers? See above for an example of a
>> dynamically allocated the ops structure.
>>
>> To me, using the ops structure seems more standard, and the dynamic allocation,
>> while not optimal, does not require much more space or complexity than the static
>> allocation. At this time it only affects one caller.
>>
>> Adding the info structure as a parameter to the register() functions adds a
>> little more complexity to all callers, whether or not they use the dynamic
>> elements of the structure.
>
> Looks like dfl is the only user of compat_id.
>
> A board specific value does not belong in a common structure, it belongs in a board structure
>
> Move compat_id out of fpga-mgr.h and into dfl.h
>
> In dfl- you can do whatever you want.

Yilun - is this a correct explanation of the use of compat_id?

I believe the compat_id is used to verify whether or not an AFU is compatible with the Static Region. When the FPGA Manager is created (for PR purposes) the compat_id is read from the Static Region and stored in the FPGA Manager. When the region is created (containing the PR region), the same compat_id is then associated with the FPGA Region. The compat_id is exported by the region via syfs to allow userspace to verify compatibility between an AFU and the static region.

And I suppose the FPGA Manager _could_ be associated with multiple regions?

So I think compat_id _is_ (optionally) an attribute of the FPGA manager and the Region.

- Russ

>
> And leave the others' ops as-is.
>
>
> Tom
>
>>
>> - Russ
>>
>>>>> +
>>>>>   static int fme_mgr_probe(struct platform_device *pdev)
>>>>>   {
>>>>>       struct dfl_fme_mgr_pdata *pdata = dev_get_platdata(&pdev->dev);
>>>>> -    struct fpga_compat_id *compat_id;
>>>>> +    struct fpga_manager_ops *fme_mgr_ops;
>>>>>       struct device *dev = &pdev->dev;
>>>>>       struct fme_mgr_priv *priv;
>>>>>       struct fpga_manager *mgr;
>>>>> @@ -302,20 +318,16 @@ static int fme_mgr_probe(struct platform_device *pdev)
>>>>>               return PTR_ERR(priv->ioaddr);
>>>>>       }
>>>>>   -    compat_id = devm_kzalloc(dev, sizeof(*compat_id), GFP_KERNEL);
>>>>> -    if (!compat_id)
>>>>> -        return -ENOMEM;
>>>>> -
>>>>> -    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)
>>>>> +    fme_mgr_ops = fme_mgr_get_ops(dev, priv);
>>>>> +    if (!fme_mgr_ops)
>>>>>           return -ENOMEM;
>>>>>   -    mgr->compat_id = compat_id;
>>>>> +    mgr = devm_fpga_mgr_register(dev, "DFL FME FPGA Manager",
>>>>> +                     fme_mgr_ops, priv);
>>>>> +    if (IS_ERR(mgr))
>>>>> +        return PTR_ERR(mgr);
>>>> With structure fpga_mgr_info, we don't need the dynamical allocation
>>>> anymore:
>>>>
>>>>     struct fpga_mgr_info minfo = { 0 };
>>>>
>>>>     minfo.name = "DFL FME FPGA Manager";
>>>>     minfo.mops = &fme_mgr_ops;
>>>>     minfo.compat_id = compat_id;
>>>>     minfo.priv = priv;
>>>>
>>>>     mgr = devm_fpga_mgr_register(dev, &minfo);
>>>>
>>>> Drivers could also leaves minfo.compat_id zero if they don't care.
>>>>
>>>> I also expect more opinions.
>>>>
>>>>>   -    return devm_fpga_mgr_register(dev, mgr);
>>>>> +    return 0;
>>>>>   }
>>>>>     static struct platform_driver fme_mgr_driver = {
>>>>> diff --git a/drivers/fpga/dfl-fme-region.c b/drivers/fpga/dfl-fme-region.c
>>>>> index 1eeb42af1012..a64c13e198a0 100644
>>>>> --- a/drivers/fpga/dfl-fme-region.c
>>>>> +++ b/drivers/fpga/dfl-fme-region.c
>>>>> @@ -46,7 +46,7 @@ static int fme_region_probe(struct platform_device *pdev)
>>>>>       }
>>>>>         region->priv = pdata;
>>>>> -    region->compat_id = mgr->compat_id;
>>>>> +    region->compat_id = mgr->mops->compat_id;
>>>> The changes should be in Patch #3, is it?
>>> This is the patch that moves compat_id out of mgr and into mgr->mops.
>>> In order to be able to compile, this patch needs the change.
>>>
>>>>>       platform_set_drvdata(pdev, region);
>>>>>         ret = fpga_region_register(region);
>>>>> diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
>>>>> index ecb4c3c795fa..9aecfea432c8 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 an 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
>>>>>    *
>>>>> - * 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
>>>>> + * 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(struct device *parent, const char *name,
>>>>> +          const struct fpga_manager_ops *mops, void *priv)
>>>> fpga_mgr_register(struct device *parent, struct fpga_mgr_info *minfo)
>>>>
>>>>>   {
>>>>>       struct fpga_manager *mgr;
>>>>>       int id, ret;
>>>>> @@ -572,21 +572,23 @@ struct fpga_manager *fpga_mgr_create(struct device *parent, const char *name,
>>>>>           !mops->write_init || (!mops->write && !mops->write_sg) ||
>>>>>           (mops->write && mops->write_sg)) {
>>>>>           dev_err(parent, "Attempt to register without fpga_manager_ops\n");
>>>>> -        return NULL;
>>>>> +        return ERR_PTR(-EINVAL);
>>>>>       }
>>>>>         if (!name || !strlen(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);
>>>>>   @@ -594,7 +596,6 @@ struct fpga_manager *fpga_mgr_create(struct device *parent, const char *name,
>>>>>       mgr->mops = mops;
>>>>>       mgr->priv = priv;
>>>>     mgr->name = minfo->name;
>>>>     mgr->mops = minfo->mops;
>>>>     mgr->priv = minfo->priv;
>>>>     mgr->compat_id = minfo->compat_id;
>>>>
>>>>>   -    device_initialize(&mgr->dev);
>>>>>       mgr->dev.class = fpga_mgr_class;
>>>>>       mgr->dev.groups = mops->groups;
>>>>>       mgr->dev.parent = parent;
>>>>> @@ -605,84 +606,6 @@ struct fpga_manager *fpga_mgr_create(struct device *parent, 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 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
>>>>> - * @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.
>>>>> - *
>>>>> - * Return: pointer to struct fpga_manager or NULL
>>>>> - */
>>>>> -struct fpga_manager *devm_fpga_mgr_create(struct device *parent, 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(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
>>>>> @@ -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,
>>>>     devm_fpga_mgr_register(struct device *parent,
>>> Yes - thanks for catching that.
>>>
>>> - Russ
>>>
>>>>> +               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 a2cea500f7cc..9155e888a133 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;
>>>>>       }
>>>>>   @@ -454,7 +447,6 @@ 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;
>>>>> 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 9b75bd4f93d8..426aa34c6a0d 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 474c1f506307..d3c6f0153457 100644
>>>>> --- a/include/linux/fpga/fpga-mgr.h
>>>>> +++ b/include/linux/fpga/fpga-mgr.h
>>>>> @@ -105,6 +105,17 @@ struct fpga_image_info {
>>>>>   #endif
>>>>>   };
>>>>>   +/**
>>>>> + * struct fpga_compat_id - id for compatibility check
>>>>> + *
>>>>> + * @id_h: high 64bit of the compat_id
>>>>> + * @id_l: low 64bit of the compat_id
>>>>> + */
>>>>> +struct fpga_compat_id {
>>>>> +    u64 id_h;
>>>>> +    u64 id_l;
>>>>> +};
>>>>> +
>>>>>   /**
>>>>>    * struct fpga_manager_ops - ops for low level fpga manager drivers
>>>>>    * @initial_header_size: Maximum number of bytes that should be passed into write_init
>>>>> @@ -116,6 +127,7 @@ struct fpga_image_info {
>>>>>    * @write_complete: set FPGA to operating state after writing is done
>>>>>    * @fpga_remove: optional: Set FPGA into a specific state during driver remove
>>>>>    * @groups: optional attribute groups.
>>>>> + * @compat_id: optional: FPGA manager id for compatibility check.
>>>>>    *
>>>>>    * fpga_manager_ops are the low level functions implemented by a specific
>>>>>    * fpga manager driver.  The optional ones are tested for NULL before being
>>>>> @@ -134,6 +146,7 @@ struct fpga_manager_ops {
>>>>>                     struct fpga_image_info *info);
>>>>>       void (*fpga_remove)(struct fpga_manager *mgr);
>>>>>       const struct attribute_group **groups;
>>>>> +    struct fpga_compat_id *compat_id;
>>>> We don't have to move compat_id here, keep it in struct fpga_mgr
>>>>
>>>> Thanks,
>>>> Yilun
>>>>
>>>>>   };
>>>>>     /* FPGA manager status: Partial/Full Reconfiguration errors */
>>>>> @@ -143,24 +156,12 @@ struct fpga_manager_ops {
>>>>>   #define FPGA_MGR_STATUS_IP_PROTOCOL_ERR        BIT(3)
>>>>>   #define FPGA_MGR_STATUS_FIFO_OVERFLOW_ERR    BIT(4)
>>>>>   -/**
>>>>> - * struct fpga_compat_id - id for compatibility check
>>>>> - *
>>>>> - * @id_h: high 64bit of the compat_id
>>>>> - * @id_l: low 64bit of the compat_id
>>>>> - */
>>>>> -struct fpga_compat_id {
>>>>> -    u64 id_h;
>>>>> -    u64 id_l;
>>>>> -};
>>>>> -
>>>>>   /**
>>>>>    * struct fpga_manager - fpga manager structure
>>>>>    * @name: name of low level fpga manager
>>>>>    * @dev: fpga manager device
>>>>>    * @ref_mutex: only allows one reference to fpga manager
>>>>>    * @state: state of fpga manager
>>>>> - * @compat_id: FPGA manager id for compatibility check.
>>>>>    * @mops: pointer to struct of fpga manager ops
>>>>>    * @priv: low level driver private date
>>>>>    */
>>>>> @@ -169,7 +170,6 @@ struct fpga_manager {
>>>>>       struct device dev;
>>>>>       struct mutex ref_mutex;
>>>>>       enum fpga_mgr_states state;
>>>>> -    struct fpga_compat_id *compat_id;
>>>>>       const struct fpga_manager_ops *mops;
>>>>>       void *priv;
>>>>>   };
>>>>> @@ -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
>