From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D4CE7C07E96 for ; Wed, 7 Jul 2021 03:07:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A920561CBA for ; Wed, 7 Jul 2021 03:07:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229996AbhGGDJp (ORCPT ); Tue, 6 Jul 2021 23:09:45 -0400 Received: from mga06.intel.com ([134.134.136.31]:18700 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229992AbhGGDJp (ORCPT ); Tue, 6 Jul 2021 23:09:45 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10037"; a="270349455" X-IronPort-AV: E=Sophos;i="5.83,330,1616482800"; d="scan'208";a="270349455" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Jul 2021 20:07:04 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.83,330,1616482800"; d="scan'208";a="486649808" Received: from yilunxu-optiplex-7050.sh.intel.com (HELO localhost) ([10.239.159.162]) by FMSMGA003.fm.intel.com with ESMTP; 06 Jul 2021 20:07:01 -0700 Date: Wed, 7 Jul 2021 11:01:37 +0800 From: Xu Yilun To: Russ Weight Cc: Tom Rix , mdf@kernel.org, linux-fpga@vger.kernel.org, lgoncalv@redhat.com, hao.wu@intel.com, matthew.gerlach@intel.com, richard.gong@intel.com Subject: Re: [PATCH v9 1/3] fpga: mgr: Use standard dev_release for class driver Message-ID: <20210707030137.GB21457@yilunxu-OptiPlex-7050> References: <20210701013733.75483-1-russell.h.weight@intel.com> <20210701013733.75483-2-russell.h.weight@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-fpga@vger.kernel.org On Tue, Jul 06, 2021 at 02:02:20PM -0700, Russ Weight wrote: > > > On 7/6/21 12:04 PM, Tom Rix wrote: > > Russ, > > > > My two big concerns are. > > > > compat_id does not belong in fpga_mgr_info, it belongs in fme_mgr_priv. > > fpga_mgr_info is a temporary structure on the stack that contains the > parameters only long enough to pass them in and have them added to the > fpga_manager structure. Do you have a concern about it being on the > fpga_manager structure. > > > > > there are two register functions, there should be one. > > I get what you are saying. I don't really like the idea of forcing the > complexity of the temporary structure on all callers, since only a > couple require it, but we can do that if that is the concensus. > > What do others think? The _register_full() function takes care of everything, but it do adds the complexity for all callers. A simpler version makes their life easier. 2 register functions is OK to me, as there are some examples in other subsystems, some of them even have 3 or more register functions. Thanks, Yilun > > > > > On 6/30/21 6:37 PM, Russ Weight wrote: > >> The FPGA manager class driver data structure is being treated as a > >> managed resource instead of using the standard dev_release call-back > >> function 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() or register_simple() function. > >> > >> The register() function accepts an info data structure to provide > >> flexibility in passing optional parameters. The register_simple() > >> function supports the current parameter list for users that don't > >> require the use of optional parameters. > >> > >> The devm_fpga_mgr_register() function is retained, and the > >> devm_fpga_mgr_register_simple() function is added. > >> > >> Signed-off-by: Russ Weight > >> Reviewed-by: Xu Yilun > >> --- > >> v9: > >>    - Cleaned up documentation for the FPGA Manager register functions > >>    - Renamed fpga_mgr_register() to fpga_mgr_register_full() > >>    - Renamed fpga_mgr_register_simple() to fpga_mgr_register() > >>    - Renamed devm_fpga_mgr_register() to devm_fpga_mgr_register_full() > >>    - Renamed devm_fpga_mgr_register_simple() to devm_fpga_mgr_register() > >> v8: > >>    - Added reviewed-by tag. > >>    - Updated Documentation/driver-api/fpga/fpga-mgr.rst documentation. > >> v7: > >>    - Update the commit message to describe the new parameters for the > >>      *fpga_mgr_register() functions and to mention the > >>      *fpga_mgr_register_simple() functions. > >>    - Fix function prototypes in header file to rename dev to parent. > >>    - Make use of the PTR_ERR_OR_ZERO() macro when possible. > >>    - Some cleanup of comments. > >>    - Update function defintions/prototypes to apply const to the new info > >>      parameter. > >> v6: > >>    - Moved FPGA manager optional parameters out of the ops structure and > >>      back into the FPGA manager structure. > >>    - Changed fpga_mgr_register()/devm_fpga_mgr_register() parameters to > >>      accept an info data structure to provide flexibility in passing optional > >>      parameters. > >>    - Added fpga_mgr_register_simple()/devm_fpga_mgr_register_simple() > >>      functions to support current parameters for users that don't require > >>      the use of optional parameters. > >> 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 > >>      dynamically allocating the dfl-fme-ops structure in order to add > >>      the appropriate compat_id. > >> 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. > >> --- > >>   Documentation/driver-api/fpga/fpga-mgr.rst |  34 +++- > >>   drivers/fpga/altera-cvp.c                  |  12 +- > >>   drivers/fpga/altera-pr-ip-core.c           |   7 +- > >>   drivers/fpga/altera-ps-spi.c               |   9 +- > >>   drivers/fpga/dfl-fme-mgr.c                 |  22 +-- > >>   drivers/fpga/fpga-mgr.c                    | 215 +++++++++------------ > >>   drivers/fpga/ice40-spi.c                   |   9 +- > >>   drivers/fpga/machxo2-spi.c                 |   9 +- > >>   drivers/fpga/socfpga-a10.c                 |  16 +- > >>   drivers/fpga/socfpga.c                     |   9 +- > >>   drivers/fpga/stratix10-soc.c               |  16 +- > >>   drivers/fpga/ts73xx-fpga.c                 |   9 +- > >>   drivers/fpga/xilinx-spi.c                  |  11 +- > >>   drivers/fpga/zynq-fpga.c                   |  16 +- > >>   drivers/fpga/zynqmp-fpga.c                 |   9 +- > >>   include/linux/fpga/fpga-mgr.h              |  62 ++++-- > >>   16 files changed, 210 insertions(+), 255 deletions(-) > >> > >> diff --git a/Documentation/driver-api/fpga/fpga-mgr.rst b/Documentation/driver-api/fpga/fpga-mgr.rst > >> index 4d926b452cb3..826ed8dc9210 100644 > >> --- a/Documentation/driver-api/fpga/fpga-mgr.rst > >> +++ b/Documentation/driver-api/fpga/fpga-mgr.rst > >> @@ -24,7 +24,7 @@ How to support a new FPGA device > >>   -------------------------------- > >>     To add another FPGA manager, write a driver that implements a set of ops.  The > >> -probe function calls fpga_mgr_register(), such as:: > >> +probe function calls fpga_mgr_register() or fpga_mgr_register_full(), such as:: > >>         static const struct fpga_manager_ops socfpga_fpga_ops = { > >>           .write_init = socfpga_fpga_ops_configure_init, > >> @@ -49,14 +49,14 @@ probe function calls fpga_mgr_register(), such as:: > >>            * them in priv > >>            */ > >>   -        mgr = devm_fpga_mgr_create(dev, "Altera SOCFPGA FPGA Manager", > >> -                       &socfpga_fpga_ops, priv); > >> -        if (!mgr) > >> -            return -ENOMEM; > >> +        mgr = fpga_mgr_register(dev, "Altera SOCFPGA FPGA Manager", > >> +                    &socfpga_fpga_ops, priv); > >> +        if (IS_ERR(mgr)) > >> +            return PTR_ERR(mgr); > >>             platform_set_drvdata(pdev, mgr); > >>   -        return fpga_mgr_register(mgr); > >> +        return 0; > >>       } > >>         static int socfpga_fpga_remove(struct platform_device *pdev) > >> @@ -68,6 +68,11 @@ probe function calls fpga_mgr_register(), such as:: > >>           return 0; > >>       } > >>   +Alternatively, the probe function could call one of the resource managed > >> +register functions, devm_fpga_mgr_register() or devm_fpga_mgr_register_full(). > >> +When these functions are used, the parameter syntax is the same, but the call > >> +to fpga_mgr_unregister() should be removed. In the above example, the > >> +socfpga_fpga_remove() function would not be required. > >>     The ops will implement whatever device specific register writes are needed to > >>   do the programming sequence for this particular FPGA.  These ops return 0 for > >> @@ -104,8 +109,13 @@ API for implementing a new FPGA Manager driver > >>   * ``fpga_mgr_states`` -  Values for :c:expr:`fpga_manager->state`. > >>   * struct fpga_manager -  the FPGA manager struct > >>   * struct fpga_manager_ops -  Low level FPGA manager driver ops > >> -* devm_fpga_mgr_create() -  Allocate and init a manager struct > >> -* fpga_mgr_register() -  Register an FPGA manager > >> +* fpga_mgr_register_full() -  Create and register an FPGA manager using the > >> +  fpga_mgr_info structure to provide the full flexibility of options > >> +* fpga_mgr_register() -  Create and register an FPGA manager using standard > >> +  arguments > >> +* devm_fpga_mgr_register_full() -  Resource managed version of > >> +  fpga_mgr_register_full() > >> +* devm_fpga_mgr_register() -  Resource managed version of fpga_mgr_register() > >>   * fpga_mgr_unregister() -  Unregister an FPGA manager > >>     .. kernel-doc:: include/linux/fpga/fpga-mgr.h > >> @@ -118,10 +128,16 @@ API for implementing a new FPGA Manager driver > >>      :functions: fpga_manager_ops > >>     .. kernel-doc:: drivers/fpga/fpga-mgr.c > >> -   :functions: devm_fpga_mgr_create > >> +   :functions: fpga_mgr_register_full > >>     .. kernel-doc:: drivers/fpga/fpga-mgr.c > >>      :functions: fpga_mgr_register > >>   +.. kernel-doc:: drivers/fpga/fpga-mgr.c > >> +   :functions: devm_fpga_mgr_register_full > >> + > >> +.. kernel-doc:: drivers/fpga/fpga-mgr.c > >> +   :functions: devm_fpga_mgr_register > >> + > >>   .. kernel-doc:: drivers/fpga/fpga-mgr.c > >>      :functions: fpga_mgr_unregister > >> 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..be0667968d33 100644 > >> --- a/drivers/fpga/altera-pr-ip-core.c > >> +++ b/drivers/fpga/altera-pr-ip-core.c > >> @@ -191,11 +191,8 @@ 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; > >> - > >> -    return devm_fpga_mgr_register(dev, mgr); > >> +    mgr = devm_fpga_mgr_register(dev, dev_name(dev), &alt_pr_ops, priv); > >> +    return PTR_ERR_OR_ZERO(mgr); > >>   } > >>   EXPORT_SYMBOL_GPL(alt_pr_register); > >>   diff --git a/drivers/fpga/altera-ps-spi.c b/drivers/fpga/altera-ps-spi.c > >> index 23bfd4d1ad0f..5e1e009dba89 100644 > >> --- a/drivers/fpga/altera-ps-spi.c > >> +++ b/drivers/fpga/altera-ps-spi.c > >> @@ -302,12 +302,9 @@ 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; > >> - > >> -    return devm_fpga_mgr_register(&spi->dev, mgr); > >> +    mgr = devm_fpga_mgr_register(&spi->dev, conf->mgr_name, > >> +                     &altera_ps_ops, conf); > >> +    return PTR_ERR_OR_ZERO(mgr); > >>   } > >>     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..620e7874ab53 100644 > >> --- a/drivers/fpga/dfl-fme-mgr.c > >> +++ b/drivers/fpga/dfl-fme-mgr.c > >> @@ -282,7 +282,7 @@ static void fme_mgr_get_compat_id(void __iomem *fme_pr, > >>   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_info info = { 0 }; > >>       struct device *dev = &pdev->dev; > >>       struct fme_mgr_priv *priv; > >>       struct fpga_manager *mgr; > >> @@ -302,20 +302,16 @@ 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) > >> +    info.name = "DFL FME FPGA Manager"; > >> +    info.mops = &fme_mgr_ops; > >> +    info.priv = priv; > >> +    info.compat_id = devm_kzalloc(dev, sizeof(*info.compat_id), GFP_KERNEL); > >> +    if (!info.compat_id) > >>           return -ENOMEM; > > could we limp along instead of failing ? > > The compat_id is used to verify compatibility between the static region and > the partial reconfiguration. If there is insufficient memory for the small > data structure, I think it is best to fail here. This is also consistent > current implementation. >   > >>   -    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->compat_id = compat_id; > >> - > >> -    return devm_fpga_mgr_register(dev, mgr); > >> +    fme_mgr_get_compat_id(priv->ioaddr, info.compat_id); > >> +    mgr = devm_fpga_mgr_register_full(dev, &info); > >> +    return PTR_ERR_OR_ZERO(mgr); > >>   } > >>     static struct platform_driver fme_mgr_driver = { > >> diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c > >> index ecb4c3c795fa..5a913aa649fd 100644 > >> --- a/drivers/fpga/fpga-mgr.c > >> +++ b/drivers/fpga/fpga-mgr.c > >> @@ -550,21 +550,19 @@ 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_full - 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 > >> + * @info:    parameters for fpga manager > >>    * > >> - * 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_full() 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_full(struct device *parent, const struct fpga_manager_info *info) > >>   { > >> +    const struct fpga_manager_ops *mops = info->mops; > >>       struct fpga_manager *mgr; > >>       int id, ret; > >>   @@ -572,29 +570,31 @@ 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)) { > >> +    if (!info->name || !strlen(info->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); > >>   -    mgr->name = name; > >> -    mgr->mops = mops; > >> -    mgr->priv = priv; > >> +    mgr->name = info->name; > >> +    mgr->mops = info->mops; > >> +    mgr->priv = info->priv; > >> +    mgr->compat_id = info->compat_id; > >>   -    device_initialize(&mgr->dev); > >>       mgr->dev.class = fpga_mgr_class; > >>       mgr->dev.groups = mops->groups; > >>       mgr->dev.parent = parent; > >> @@ -605,6 +605,19 @@ struct fpga_manager *fpga_mgr_create(struct device *parent, const char *name, > >>       if (ret) > >>           goto error_device; > >>   +    /* > >> +     * Initialize framework state by requesting low level driver read state > >> +     * from device.  FPGA may be in reset mode or may have been programmed > >> +     * by bootloader or EEPROM. > >> +     */ > >> +    mgr->state = mgr->mops->state(mgr); > > > > This is existing code, but it seems wrong. > > > > A side effect of state() should not be to initialize. > > > > An init() should be added to mops > > I think this is just capturing the state of the underlying device an > reflecting it in the fpga-manager state? Maybe someone else can comment > on this. It seems outside the scope of these patches. > > > > >> + > >> +    ret = device_register(&mgr->dev); > >> +    if (ret) { > >> +        put_device(&mgr->dev); > >> +        return ERR_PTR(ret); > >> +    } > >> + > >>       return mgr; > >>     error_device: > >> @@ -612,96 +625,36 @@ struct fpga_manager *fpga_mgr_create(struct device *parent, const char *name, > >>   error_kfree: > >>       kfree(mgr); > >>   -    return NULL; > >> +    return ERR_PTR(ret); > >>   } > >> -EXPORT_SYMBOL_GPL(fpga_mgr_create); > >> +EXPORT_SYMBOL_GPL(fpga_mgr_register_full); > >>     /** > >> - * 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 > >> + * 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 > >>    * > >> - * 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. > >> + * The caller of this function is responsible for calling fpga_mgr_unregister(). > >> + * Using devm_fpga_mgr_register() instead is recommended. This simple > >> + * version of the register function should be sufficient for most users. The > >> + * fpga_mgr_register_full() function is available for users that need to pass > >> + * additional, optional parameters. > >>    * > >> - * Return: pointer to struct fpga_manager or NULL > >> + * Return: pointer to struct fpga_manager pointer or ERR_PTR() > >>    */ > >> -struct fpga_manager *devm_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) > >>   { > >> -    struct fpga_mgr_devres *dr; > >> +    struct fpga_manager_info info = { 0 }; > >>   -    dr = devres_alloc(devm_fpga_mgr_release, sizeof(*dr), GFP_KERNEL); > >> -    if (!dr) > >> -        return NULL; > >> +    info.name = name; > >> +    info.mops = mops; > >> +    info.priv = priv; > >>   -    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 > >> -     * by bootloader or EEPROM. > >> -     */ > >> -    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); > >> - > >> -    return 0; > >> - > >> -error_device: > >> -    ida_simple_remove(&fpga_mgr_ida, mgr->dev.id); > >> - > >> -    return ret; > >> +    return fpga_mgr_register_full(parent, &info); > >>   } > >>   EXPORT_SYMBOL_GPL(fpga_mgr_register); > >>   @@ -726,14 +679,6 @@ 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; > >> @@ -742,45 +687,67 @@ 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 > >> + * devm_fpga_mgr_register_full - resource managed variant of fpga_mgr_register() > >> + * @parent:    fpga manager device from pdev > >> + * @info:    parameters for fpga manager > >>    * > >> - * This is the devres variant of fpga_mgr_register() for which the unregister > >> + * This is the devres variant of fpga_mgr_register_full() 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_full(struct device *parent, const struct fpga_manager_info *info) > >>   { > >>       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_full(parent, info); > >> +    if (IS_ERR(mgr)) { > >>           devres_free(dr); > >> -        return ret; > >> +        return mgr; > >>       } > >>         dr->mgr = mgr; > >> -    devres_add(dev, dr); > >> +    devres_add(parent, dr); > >>   -    return 0; > >> +    return mgr; > >> +} > >> +EXPORT_SYMBOL_GPL(devm_fpga_mgr_register_full); > >> + > >> +/** > >> + * devm_fpga_mgr_register - resource managed variant of fpga_mgr_register() > >> + * @parent:    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. > >> + */ > >> +struct fpga_manager * > >> +devm_fpga_mgr_register(struct device *parent, const char *name, > >> +               const struct fpga_manager_ops *mops, void *priv) > >> +{ > >> +    struct fpga_manager_info info = { 0 }; > >> + > >> +    info.name = name; > >> +    info.mops = mops; > >> +    info.priv = priv; > >> + > >> +    return devm_fpga_mgr_register_full(parent, &info); > >>   } > >>   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..b7591912248f 100644 > >> --- a/drivers/fpga/ice40-spi.c > >> +++ b/drivers/fpga/ice40-spi.c > >> @@ -178,12 +178,9 @@ 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; > >> - > >> -    return devm_fpga_mgr_register(dev, mgr); > >> +    mgr = devm_fpga_mgr_register(dev, "Lattice iCE40 FPGA Manager", > >> +                     &ice40_fpga_ops, priv); > >> +    return PTR_ERR_OR_ZERO(mgr); > >>   } > >>     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 1afb41aa20d7..8469dfb5dd21 100644 > >> --- a/drivers/fpga/machxo2-spi.c > >> +++ b/drivers/fpga/machxo2-spi.c > >> @@ -366,12 +366,9 @@ 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; > >> - > >> -    return devm_fpga_mgr_register(dev, mgr); > >> +    mgr = devm_fpga_mgr_register(dev, "Lattice MachXO2 SPI FPGA Manager", > >> +                     &machxo2_ops, spi); > >> +    return PTR_ERR_OR_ZERO(mgr); > >>   } > >>     #ifdef CONFIG_OF > >> 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..7e0741f99696 100644 > >> --- a/drivers/fpga/socfpga.c > >> +++ b/drivers/fpga/socfpga.c > >> @@ -571,12 +571,9 @@ 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; > >> - > >> -    return devm_fpga_mgr_register(dev, mgr); > >> +    mgr = devm_fpga_mgr_register(dev, "Altera SOCFPGA FPGA Manager", > >> +                     &socfpga_fpga_ops, priv); > >> +    return PTR_ERR_OR_ZERO(mgr); > >>   } > >>     #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..fd52de20ddb2 100644 > >> --- a/drivers/fpga/ts73xx-fpga.c > >> +++ b/drivers/fpga/ts73xx-fpga.c > >> @@ -122,12 +122,9 @@ 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; > >> - > >> -    return devm_fpga_mgr_register(kdev, mgr); > >> +    mgr = devm_fpga_mgr_register(kdev, "TS-73xx FPGA Manager", > >> +                     &ts73xx_fpga_ops, priv); > >> +    return PTR_ERR_OR_ZERO(mgr); > >>   } > >>     static struct platform_driver ts73xx_fpga_driver = { > >> diff --git a/drivers/fpga/xilinx-spi.c b/drivers/fpga/xilinx-spi.c > >> index fee4d0abf6bf..db23626f9ab2 100644 > >> --- a/drivers/fpga/xilinx-spi.c > >> +++ b/drivers/fpga/xilinx-spi.c > >> @@ -247,13 +247,10 @@ 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; > >> - > >> -    return devm_fpga_mgr_register(&spi->dev, mgr); > >> +    mgr = devm_fpga_mgr_register(&spi->dev, > >> +                     "Xilinx Slave Serial FPGA Manager", > >> +                     &xilinx_spi_ops, conf); > >> +    return PTR_ERR_OR_ZERO(mgr); > >>   } > >>     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..975bdc4d0a65 100644 > >> --- a/drivers/fpga/zynqmp-fpga.c > >> +++ b/drivers/fpga/zynqmp-fpga.c > >> @@ -102,12 +102,9 @@ 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; > >> - > >> -    return devm_fpga_mgr_register(dev, mgr); > >> +    mgr = devm_fpga_mgr_register(dev, "Xilinx ZynqMP FPGA Manager", > >> +                     &zynqmp_fpga_ops, priv); > >> +    return PTR_ERR_OR_ZERO(mgr); > >>   } > >>     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..ac3ddaf2903c 100644 > >> --- a/include/linux/fpga/fpga-mgr.h > >> +++ b/include/linux/fpga/fpga-mgr.h > >> @@ -105,6 +105,36 @@ 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; > >> +}; > >> + > > > > There are two register functions are to handle this dfl only structure. > > > > This really needs to be moved fme_mgr_priv. > > > >> +/** > >> + * struct fpga_manager_info - collection of parameters for an FPGA Manager > >> + * @name: fpga manager name > >> + * @compat_id: FPGA manager id for compatibility check. > >> + * @mops: pointer to structure of fpga manager ops > >> + * @priv: fpga manager private data > >> + * > >> + * fpga_manager_info contains parameters for the register function. These > >> + * are separated into an info structure because they some are optional > >> + * others could be added to in the future. The info structure facilitates > >> + * maintaining a stable API. > >> + */ > >> +struct fpga_manager_info { > >> +    const char *name; > >> +    struct fpga_compat_id *compat_id; > >> +    const struct fpga_manager_ops *mops; > >> +    void *priv; > >> +}; > >> + > >>   /** > >>    * 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 > >> @@ -143,17 +173,6 @@ 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 > >> @@ -191,17 +210,18 @@ 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); > > > > removing these should cause any oot driver to fail to load. > > > > so an oops is unlikely. > > > > I'm ok with with api change. > > > >> -int fpga_mgr_register(struct fpga_manager *mgr); > >> -void fpga_mgr_unregister(struct fpga_manager *mgr); > >> +struct fpga_manager * > >> +fpga_mgr_register_full(struct device *parent, const struct fpga_manager_info *info); > >>   -int devm_fpga_mgr_register(struct device *dev, struct fpga_manager *mgr); > >> +struct fpga_manager * > >> +fpga_mgr_register(struct device *parent, const char *name, > >> +          const struct fpga_manager_ops *mops, void *priv); > > > > having 2 ways to do the same thing is not great. > > > > this should be reduced down to 1. > > > > My preference is for the *info one as it's api will be durable. > > I would like to see if other's agree. > > > > > Tom > > > >> +void fpga_mgr_unregister(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_full(struct device *parent, const struct fpga_manager_info *info); > >> +struct fpga_manager * > >> +devm_fpga_mgr_register(struct device *parent, const char *name, > >> +               const struct fpga_manager_ops *mops, void *priv); > >>     #endif /*_LINUX_FPGA_MGR_H */ > >