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 A0E8BC11F64 for ; Thu, 1 Jul 2021 06:32:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7BBE46145A for ; Thu, 1 Jul 2021 06:32:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234268AbhGAGev (ORCPT ); Thu, 1 Jul 2021 02:34:51 -0400 Received: from mga14.intel.com ([192.55.52.115]:57694 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233878AbhGAGev (ORCPT ); Thu, 1 Jul 2021 02:34:51 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10031"; a="208301649" X-IronPort-AV: E=Sophos;i="5.83,313,1616482800"; d="scan'208";a="208301649" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Jun 2021 23:32:18 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.83,313,1616482800"; d="scan'208";a="476548672" Received: from yilunxu-optiplex-7050.sh.intel.com (HELO localhost) ([10.239.159.162]) by fmsmga004.fm.intel.com with ESMTP; 30 Jun 2021 23:32:16 -0700 Date: Thu, 1 Jul 2021 14:26:55 +0800 From: Xu Yilun To: Russ Weight Cc: mdf@kernel.org, linux-fpga@vger.kernel.org, trix@redhat.com, lgoncalv@redhat.com, hao.wu@intel.com, matthew.gerlach@intel.com, richard.gong@intel.com Subject: Re: [PATCH v9 2/3] fpga: bridge: Use standard dev_release for class driver Message-ID: <20210701062655.GD96355@yilunxu-OptiPlex-7050> References: <20210701013733.75483-1-russell.h.weight@intel.com> <20210701013733.75483-3-russell.h.weight@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210701013733.75483-3-russell.h.weight@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-fpga@vger.kernel.org On Wed, Jun 30, 2021 at 06:37:32PM -0700, Russ Weight wrote: > The FPGA bridge 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 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. > > Signed-off-by: Russ Weight > Reviewed-by: Xu Yilun > --- > v9: > - Cleaned up documentation for the FPGA Bridge register functions > - Renamed fpga_bridge_register() to fpga_bridge_register_full() > - Renamed fpga_bridge_register_simple() to fpga_bridge_register() Now we come back to the fpga_XXX_register for normal cases and fpga_XXX_register_full for extra parameters. But the fpga_bridge_register_full has no use case yet, should we implement it when it is really needed? Thanks, Yilun > v8: > - Added reviewed-by tag. > - Updated Documentation/driver-api/fpga/fpga-bridge.rst documentation. > v7: > - Update the commit message to describe the new parameters for the > fpga_bridge_register() function and to mention the > fpga_bridge_register_simple() function. > - Fix function prototypes in header file to rename dev to parent. > - Some cleanup of comments. > - Update function defintions/prototypes to apply const to the new info > parameter. > - Verify that info->br_ops is non-null in register functions. > v6: > - Changed fpga_bridge_register() parameters to accept an info data > structure to provide flexibility in passing optional parameters. > - Added fpga_bridge_register_simple() function to support current > parameters for users that don't require the use of optional > parameters. > v5: > - Rebased on top of recently accepted patches. > v4: > - Restore the previous format for the Return value in the comment header > for fpga_bridge_register() > v3: > - Cleaned up comment header for fpga_bridge_register() > - Fix error return values for fpga_bridge_register() > v2: > - No changes > --- > Documentation/driver-api/fpga/fpga-bridge.rst | 8 +- > drivers/fpga/altera-fpga2sdram.c | 12 +- > drivers/fpga/altera-freeze-bridge.c | 10 +- > drivers/fpga/altera-hps2fpga.c | 12 +- > drivers/fpga/dfl-fme-br.c | 10 +- > drivers/fpga/fpga-bridge.c | 137 ++++++------------ > drivers/fpga/xilinx-pr-decoupler.c | 17 +-- > include/linux/fpga/fpga-bridge.h | 33 +++-- > 8 files changed, 101 insertions(+), 138 deletions(-) > > diff --git a/Documentation/driver-api/fpga/fpga-bridge.rst b/Documentation/driver-api/fpga/fpga-bridge.rst > index 8d650b4e2ce6..38e3bac8e877 100644 > --- a/Documentation/driver-api/fpga/fpga-bridge.rst > +++ b/Documentation/driver-api/fpga/fpga-bridge.rst > @@ -6,8 +6,10 @@ API to implement a new FPGA bridge > > * struct fpga_bridge - The FPGA Bridge structure > * struct fpga_bridge_ops - Low level Bridge driver ops > -* devm_fpga_bridge_create() - Allocate and init a bridge struct > -* fpga_bridge_register() - Register a bridge > +* fpga_bridge_register_full() - Create and register a bridge using the > + fpga_bridge_info structure to provide the full flexibility of options > +* fpga_bridge_register() - Create and register a bridge using standard > + arguments > * fpga_bridge_unregister() - Unregister a bridge > > .. kernel-doc:: include/linux/fpga/fpga-bridge.h > @@ -17,7 +19,7 @@ API to implement a new FPGA bridge > :functions: fpga_bridge_ops > > .. kernel-doc:: drivers/fpga/fpga-bridge.c > - :functions: devm_fpga_bridge_create > + :functions: fpga_bridge_register_full > > .. kernel-doc:: drivers/fpga/fpga-bridge.c > :functions: fpga_bridge_register > diff --git a/drivers/fpga/altera-fpga2sdram.c b/drivers/fpga/altera-fpga2sdram.c > index a78e49c63c64..66063507116b 100644 > --- a/drivers/fpga/altera-fpga2sdram.c > +++ b/drivers/fpga/altera-fpga2sdram.c > @@ -121,17 +121,13 @@ static int alt_fpga_bridge_probe(struct platform_device *pdev) > /* Get f2s bridge configuration saved in handoff register */ > regmap_read(sysmgr, SYSMGR_ISWGRP_HANDOFF3, &priv->mask); > > - br = devm_fpga_bridge_create(dev, F2S_BRIDGE_NAME, > - &altera_fpga2sdram_br_ops, priv); > - if (!br) > - return -ENOMEM; > + br = fpga_bridge_register(dev, F2S_BRIDGE_NAME, > + &altera_fpga2sdram_br_ops, priv); > + if (IS_ERR(br)) > + return PTR_ERR(mgr); > > platform_set_drvdata(pdev, br); > > - ret = fpga_bridge_register(br); > - if (ret) > - return ret; > - > dev_info(dev, "driver initialized with handoff %08x\n", priv->mask); > > if (!of_property_read_u32(dev->of_node, "bridge-enable", &enable)) { > diff --git a/drivers/fpga/altera-freeze-bridge.c b/drivers/fpga/altera-freeze-bridge.c > index dd58c4aea92e..bfbfa43cd05b 100644 > --- a/drivers/fpga/altera-freeze-bridge.c > +++ b/drivers/fpga/altera-freeze-bridge.c > @@ -244,14 +244,14 @@ static int altera_freeze_br_probe(struct platform_device *pdev) > > priv->base_addr = base_addr; > > - br = devm_fpga_bridge_create(dev, FREEZE_BRIDGE_NAME, > - &altera_freeze_br_br_ops, priv); > - if (!br) > - return -ENOMEM; > + br = fpga_bridge_register(dev, FREEZE_BRIDGE_NAME, > + &altera_freeze_br_br_ops, priv); > + if (IS_ERR(br)) > + return PTR_ERR(br); > > platform_set_drvdata(pdev, br); > > - return fpga_bridge_register(br); > + return 0; > } > > static int altera_freeze_br_remove(struct platform_device *pdev) > diff --git a/drivers/fpga/altera-hps2fpga.c b/drivers/fpga/altera-hps2fpga.c > index 77b95f251821..aa758426c22b 100644 > --- a/drivers/fpga/altera-hps2fpga.c > +++ b/drivers/fpga/altera-hps2fpga.c > @@ -180,19 +180,15 @@ static int alt_fpga_bridge_probe(struct platform_device *pdev) > } > } > > - br = devm_fpga_bridge_create(dev, priv->name, > - &altera_hps2fpga_br_ops, priv); > - if (!br) { > - ret = -ENOMEM; > + br = fpga_bridge_register(dev, priv->name, > + &altera_hps2fpga_br_ops, priv); > + if (IS_ERR(br)) { > + ret = PTR_ERR(br); > goto err; > } > > platform_set_drvdata(pdev, br); > > - ret = fpga_bridge_register(br); > - if (ret) > - goto err; > - > return 0; > > err: > diff --git a/drivers/fpga/dfl-fme-br.c b/drivers/fpga/dfl-fme-br.c > index 3ff9f3a687ce..808d1f4d76df 100644 > --- a/drivers/fpga/dfl-fme-br.c > +++ b/drivers/fpga/dfl-fme-br.c > @@ -68,14 +68,14 @@ static int fme_br_probe(struct platform_device *pdev) > > priv->pdata = dev_get_platdata(dev); > > - br = devm_fpga_bridge_create(dev, "DFL FPGA FME Bridge", > - &fme_bridge_ops, priv); > - if (!br) > - return -ENOMEM; > + br = fpga_bridge_register(dev, "DFL FPGA FME Bridge", > + &fme_bridge_ops, priv); > + if (IS_ERR(br)) > + return PTR_ERR(br); > > platform_set_drvdata(pdev, br); > > - return fpga_bridge_register(br); > + return 0; > } > > static int fme_br_remove(struct platform_device *pdev) > diff --git a/drivers/fpga/fpga-bridge.c b/drivers/fpga/fpga-bridge.c > index 798f55670646..e6d98be8531b 100644 > --- a/drivers/fpga/fpga-bridge.c > +++ b/drivers/fpga/fpga-bridge.c > @@ -312,55 +312,63 @@ static struct attribute *fpga_bridge_attrs[] = { > ATTRIBUTE_GROUPS(fpga_bridge); > > /** > - * fpga_bridge_create - create and initialize a struct fpga_bridge > + * fpga_bridge_register_full - create and register an FPGA Bridge device > * @parent: FPGA bridge device from pdev > - * @name: FPGA bridge name > - * @br_ops: pointer to structure of fpga bridge ops > - * @priv: FPGA bridge private data > + * @info: parameters for FPGA Bridge > * > - * The caller of this function is responsible for freeing the bridge with > - * fpga_bridge_free(). Using devm_fpga_bridge_create() instead is recommended. > - * > - * Return: struct fpga_bridge or NULL > + * Return: struct fpga_bridge pointer or ERR_PTR() > */ > -struct fpga_bridge *fpga_bridge_create(struct device *parent, const char *name, > - const struct fpga_bridge_ops *br_ops, > - void *priv) > +struct fpga_bridge * > +fpga_bridge_register_full(struct device *parent, > + const struct fpga_bridge_info *info) > { > struct fpga_bridge *bridge; > int id, ret; > > - if (!name || !strlen(name)) { > + if (!info->br_ops) { > + dev_err(parent, "Attempt to register without fpga_bridge_ops\n"); > + return ERR_PTR(-EINVAL); > + } > + > + if (!info->name || !strlen(info->name)) { > dev_err(parent, "Attempt to register with no name!\n"); > - return NULL; > + return ERR_PTR(-EINVAL); > } > > bridge = kzalloc(sizeof(*bridge), GFP_KERNEL); > if (!bridge) > - return NULL; > + return ERR_PTR(-ENOMEM); > > id = ida_simple_get(&fpga_bridge_ida, 0, 0, GFP_KERNEL); > - if (id < 0) > + if (id < 0) { > + ret = id; > goto error_kfree; > + } > > mutex_init(&bridge->mutex); > INIT_LIST_HEAD(&bridge->node); > > - bridge->name = name; > - bridge->br_ops = br_ops; > - bridge->priv = priv; > + bridge->name = info->name; > + bridge->br_ops = info->br_ops; > + bridge->priv = info->priv; > > - device_initialize(&bridge->dev); > - bridge->dev.groups = br_ops->groups; > + bridge->dev.groups = info->br_ops->groups; > bridge->dev.class = fpga_bridge_class; > bridge->dev.parent = parent; > bridge->dev.of_node = parent->of_node; > bridge->dev.id = id; > + of_platform_populate(bridge->dev.of_node, NULL, NULL, &bridge->dev); > > ret = dev_set_name(&bridge->dev, "br%d", id); > if (ret) > goto error_device; > > + ret = device_register(&bridge->dev); > + if (ret) { > + put_device(&bridge->dev); > + return ERR_PTR(ret); > + } > + > return bridge; > > error_device: > @@ -368,88 +376,35 @@ struct fpga_bridge *fpga_bridge_create(struct device *parent, const char *name, > error_kfree: > kfree(bridge); > > - return NULL; > -} > -EXPORT_SYMBOL_GPL(fpga_bridge_create); > - > -/** > - * fpga_bridge_free - free an fpga bridge created by fpga_bridge_create() > - * @bridge: FPGA bridge struct > - */ > -void fpga_bridge_free(struct fpga_bridge *bridge) > -{ > - ida_simple_remove(&fpga_bridge_ida, bridge->dev.id); > - kfree(bridge); > -} > -EXPORT_SYMBOL_GPL(fpga_bridge_free); > - > -static void devm_fpga_bridge_release(struct device *dev, void *res) > -{ > - struct fpga_bridge *bridge = *(struct fpga_bridge **)res; > - > - fpga_bridge_free(bridge); > + return ERR_PTR(ret); > } > +EXPORT_SYMBOL_GPL(fpga_bridge_register_full); > > /** > - * devm_fpga_bridge_create - create and init a managed struct fpga_bridge > + * fpga_bridge_register - create and register an FPGA Bridge device > * @parent: FPGA bridge device from pdev > * @name: FPGA bridge name > * @br_ops: pointer to structure of fpga bridge ops > * @priv: FPGA bridge private data > * > - * This function is intended for use in an FPGA bridge driver's probe function. > - * After the bridge driver creates the struct with devm_fpga_bridge_create(), it > - * should register the bridge with fpga_bridge_register(). The bridge driver's > - * remove function should call fpga_bridge_unregister(). The bridge struct > - * allocated with this function will be freed automatically on driver detach. > - * This includes the case of a probe function returning error before calling > - * fpga_bridge_register(), the struct will still get cleaned up. > + * This simple version of the register should be sufficient for most users. > + * The fpga_bridge_register_full() function is available for users that need to pass > + * additional, optional parameters. > * > - * Return: struct fpga_bridge or NULL > + * Return: struct fpga_bridge pointer or ERR_PTR() > */ > -struct fpga_bridge > -*devm_fpga_bridge_create(struct device *parent, const char *name, > - const struct fpga_bridge_ops *br_ops, void *priv) > +struct fpga_bridge * > +fpga_bridge_register(struct device *parent, const char *name, > + const struct fpga_bridge_ops *br_ops, > + void *priv) > { > - struct fpga_bridge **ptr, *bridge; > - > - ptr = devres_alloc(devm_fpga_bridge_release, sizeof(*ptr), GFP_KERNEL); > - if (!ptr) > - return NULL; > - > - bridge = fpga_bridge_create(parent, name, br_ops, priv); > - if (!bridge) { > - devres_free(ptr); > - } else { > - *ptr = bridge; > - devres_add(parent, ptr); > - } > + struct fpga_bridge_info info = { 0 }; > > - return bridge; > -} > -EXPORT_SYMBOL_GPL(devm_fpga_bridge_create); > + info.name = name; > + info.br_ops = br_ops; > + info.priv = priv; > > -/** > - * fpga_bridge_register - register an FPGA bridge > - * > - * @bridge: FPGA bridge struct > - * > - * Return: 0 for success, error code otherwise. > - */ > -int fpga_bridge_register(struct fpga_bridge *bridge) > -{ > - struct device *dev = &bridge->dev; > - int ret; > - > - ret = device_add(dev); > - if (ret) > - return ret; > - > - of_platform_populate(dev->of_node, NULL, NULL, dev); > - > - dev_info(dev->parent, "fpga bridge [%s] registered\n", bridge->name); > - > - return 0; > + return fpga_bridge_register_full(parent, &info); > } > EXPORT_SYMBOL_GPL(fpga_bridge_register); > > @@ -475,6 +430,10 @@ EXPORT_SYMBOL_GPL(fpga_bridge_unregister); > > static void fpga_bridge_dev_release(struct device *dev) > { > + struct fpga_bridge *bridge = to_fpga_bridge(dev); > + > + ida_simple_remove(&fpga_bridge_ida, bridge->dev.id); > + kfree(bridge); > } > > static int __init fpga_bridge_dev_init(void) > diff --git a/drivers/fpga/xilinx-pr-decoupler.c b/drivers/fpga/xilinx-pr-decoupler.c > index ea2bde6e5bc4..c004e52b9464 100644 > --- a/drivers/fpga/xilinx-pr-decoupler.c > +++ b/drivers/fpga/xilinx-pr-decoupler.c > @@ -138,22 +138,17 @@ static int xlnx_pr_decoupler_probe(struct platform_device *pdev) > > clk_disable(priv->clk); > > - br = devm_fpga_bridge_create(&pdev->dev, priv->ipconfig->name, > - &xlnx_pr_decoupler_br_ops, priv); > - if (!br) { > - err = -ENOMEM; > - goto err_clk; > - } > - > - platform_set_drvdata(pdev, br); > - > - err = fpga_bridge_register(br); > - if (err) { > + br = fpga_bridge_register(&pdev->dev, priv->ipconfig->name, > + &xlnx_pr_decoupler_br_ops, priv); > + if (IS_ERR(br)) { > + err = PTR_ERR(br); > dev_err(&pdev->dev, "unable to register %s", > priv->ipconfig->name); > goto err_clk; > } > > + platform_set_drvdata(pdev, br); > + > return 0; > > err_clk: > diff --git a/include/linux/fpga/fpga-bridge.h b/include/linux/fpga/fpga-bridge.h > index 6c3c28806ff1..f0a4d99d9c8e 100644 > --- a/include/linux/fpga/fpga-bridge.h > +++ b/include/linux/fpga/fpga-bridge.h > @@ -22,6 +22,23 @@ struct fpga_bridge_ops { > const struct attribute_group **groups; > }; > > +/** > + * struct fpga_bridge_info - collection of parameters an FPGA Bridge > + * @name: fpga bridge name > + * @br_ops: pointer to structure of fpga bridge ops > + * @priv: fpga bridge private data > + * > + * fpga_bridge_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_bridge_info { > + const char *name; > + const struct fpga_bridge_ops *br_ops; > + void *priv; > +}; > + > /** > * struct fpga_bridge - FPGA bridge structure > * @name: name of low level FPGA bridge > @@ -62,15 +79,13 @@ int of_fpga_bridge_get_to_list(struct device_node *np, > struct fpga_image_info *info, > struct list_head *bridge_list); > > -struct fpga_bridge *fpga_bridge_create(struct device *dev, const char *name, > - const struct fpga_bridge_ops *br_ops, > - void *priv); > -void fpga_bridge_free(struct fpga_bridge *br); > -int fpga_bridge_register(struct fpga_bridge *br); > -void fpga_bridge_unregister(struct fpga_bridge *br); > +struct fpga_bridge * > +fpga_bridge_register_full(struct device *parent, const struct fpga_bridge_info *info); > > -struct fpga_bridge > -*devm_fpga_bridge_create(struct device *dev, const char *name, > - const struct fpga_bridge_ops *br_ops, void *priv); > +struct fpga_bridge * > +fpga_bridge_register(struct device *parent, const char *name, > + const struct fpga_bridge_ops *br_ops, > + void *priv); > +void fpga_bridge_unregister(struct fpga_bridge *br); > > #endif /* _LINUX_FPGA_BRIDGE_H */ > -- > 2.25.1