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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 0A51DC07E96 for ; Tue, 6 Jul 2021 23:08:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DAE4461CAA for ; Tue, 6 Jul 2021 23:08:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229910AbhGFXLT (ORCPT ); Tue, 6 Jul 2021 19:11:19 -0400 Received: from mga18.intel.com ([134.134.136.126]:32478 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229891AbhGFXLT (ORCPT ); Tue, 6 Jul 2021 19:11:19 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10037"; a="196490406" X-IronPort-AV: E=Sophos;i="5.83,330,1616482800"; d="scan'208";a="196490406" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Jul 2021 16:08:40 -0700 X-IronPort-AV: E=Sophos;i="5.83,330,1616482800"; d="scan'208";a="457240167" Received: from rhweight-mobl2.amr.corp.intel.com (HELO [10.0.2.4]) ([10.209.123.96]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Jul 2021 16:08:39 -0700 Subject: Re: [PATCH v9 2/3] fpga: bridge: Use standard dev_release for class driver To: Xu Yilun 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 References: <20210701013733.75483-1-russell.h.weight@intel.com> <20210701013733.75483-3-russell.h.weight@intel.com> <20210701062655.GD96355@yilunxu-OptiPlex-7050> From: Russ Weight Message-ID: Date: Tue, 6 Jul 2021 16:08:27 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: <20210701062655.GD96355@yilunxu-OptiPlex-7050> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: linux-fpga@vger.kernel.org On 6/30/21 11:26 PM, Xu Yilun wrote: > 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? I was just trying to maintain consistency throughout the framework. I can remove the unused fpga_bridge_register_full() function. - Russ > > 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