diff --git a/Documentation/driver-api/fpga/fpga-bridge.rst b/Documentation/driver-api/fpga/fpga-bridge.rst index 198aadafd3e7d353423fb92f2ca4b4edbb373a2c..da08605a3a11f05a4e1c893a37a3189cc1072530 100644 --- a/Documentation/driver-api/fpga/fpga-bridge.rst +++ b/Documentation/driver-api/fpga/fpga-bridge.rst @@ -6,10 +6,12 @@ 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() — Create and register a bridge * fpga_bridge_unregister() — Unregister a bridge +The helper macro ``fpga_bridge_register()`` automatically sets +the module that registers the FPGA bridge as the owner. + .. kernel-doc:: include/linux/fpga/fpga-bridge.h :functions: fpga_bridge @@ -17,10 +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 - -.. kernel-doc:: drivers/fpga/fpga-bridge.c - :functions: fpga_bridge_register + :functions: __fpga_bridge_register .. kernel-doc:: drivers/fpga/fpga-bridge.c :functions: fpga_bridge_unregister diff --git a/drivers/fpga/altera-fpga2sdram.c b/drivers/fpga/altera-fpga2sdram.c index a78e49c63c640d3fb8313d6015bd6af9f0607e80..ff3a646fd9e32fab30acef6a4a4e373c85a7c697 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(br); 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 dd58c4aea92ea6c7c33ea70c628d1642c28d4df7..bfbfa43cd05bc2496cfeff0a37e94f892e577c9c 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 77b95f2518216863bdba6c80c38e329c51912cc5..aa758426c22bcd5fec39dc9c31c8b2991a043dee 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 3ff9f3a687ce52b3399b5c06ce4a1b91eec52621..808d1f4d76df8f3f69569f598cc6ad1c9b73c47d 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 851debe32bf0f557832362efec3684bd7323633a..0896db7f9ab32d61f0271d79f57664662ba7e334 100644 --- a/drivers/fpga/fpga-bridge.c +++ b/drivers/fpga/fpga-bridge.c @@ -30,7 +30,7 @@ int fpga_bridge_enable(struct fpga_bridge *bridge) { dev_dbg(&bridge->dev, "enable\n"); - if (bridge->br_ops && bridge->br_ops->enable_set) + if (bridge->br_ops->enable_set) return bridge->br_ops->enable_set(bridge, 1); return 0; @@ -48,40 +48,33 @@ int fpga_bridge_disable(struct fpga_bridge *bridge) { dev_dbg(&bridge->dev, "disable\n"); - if (bridge->br_ops && bridge->br_ops->enable_set) + if (bridge->br_ops->enable_set) return bridge->br_ops->enable_set(bridge, 0); return 0; } EXPORT_SYMBOL_GPL(fpga_bridge_disable); -static struct fpga_bridge *__fpga_bridge_get(struct device *dev, +static struct fpga_bridge *__fpga_bridge_get(struct device *bridge_dev, struct fpga_image_info *info) { struct fpga_bridge *bridge; - int ret = -ENODEV; - bridge = to_fpga_bridge(dev); + bridge = to_fpga_bridge(bridge_dev); bridge->info = info; - if (!mutex_trylock(&bridge->mutex)) { - ret = -EBUSY; - goto err_dev; - } + if (!mutex_trylock(&bridge->mutex)) + return ERR_PTR(-EBUSY); - if (!try_module_get(dev->parent->driver->owner)) - goto err_ll_mod; + if (!try_module_get(bridge->br_ops_owner)) { + mutex_unlock(&bridge->mutex); + return ERR_PTR(-ENODEV); + } dev_dbg(&bridge->dev, "get\n"); return bridge; - -err_ll_mod: - mutex_unlock(&bridge->mutex); -err_dev: - put_device(dev); - return ERR_PTR(ret); } /** @@ -97,13 +90,18 @@ static struct fpga_bridge *__fpga_bridge_get(struct device *dev, struct fpga_bridge *of_fpga_bridge_get(struct device_node *np, struct fpga_image_info *info) { - struct device *dev; + struct fpga_bridge *bridge; + struct device *bridge_dev; - dev = class_find_device_by_of_node(fpga_bridge_class, np); - if (!dev) + bridge_dev = class_find_device_by_of_node(fpga_bridge_class, np); + if (!bridge_dev) return ERR_PTR(-ENODEV); - return __fpga_bridge_get(dev, info); + bridge = __fpga_bridge_get(bridge_dev, info); + if (IS_ERR(bridge)) + put_device(bridge_dev); + + return bridge; } EXPORT_SYMBOL_GPL(of_fpga_bridge_get); @@ -124,6 +122,7 @@ static int fpga_bridge_dev_match(struct device *dev, const void *data) struct fpga_bridge *fpga_bridge_get(struct device *dev, struct fpga_image_info *info) { + struct fpga_bridge *bridge; struct device *bridge_dev; bridge_dev = class_find_device(fpga_bridge_class, NULL, dev, @@ -131,7 +130,11 @@ struct fpga_bridge *fpga_bridge_get(struct device *dev, if (!bridge_dev) return ERR_PTR(-ENODEV); - return __fpga_bridge_get(bridge_dev, info); + bridge = __fpga_bridge_get(bridge_dev, info); + if (IS_ERR(bridge)) + put_device(bridge_dev); + + return bridge; } EXPORT_SYMBOL_GPL(fpga_bridge_get); @@ -145,7 +148,7 @@ void fpga_bridge_put(struct fpga_bridge *bridge) dev_dbg(&bridge->dev, "put\n"); bridge->info = NULL; - module_put(bridge->dev.parent->driver->owner); + module_put(bridge->br_ops_owner); mutex_unlock(&bridge->mutex); put_device(&bridge->dev); } @@ -295,7 +298,7 @@ static ssize_t state_show(struct device *dev, struct fpga_bridge *bridge = to_fpga_bridge(dev); int enable = 1; - if (bridge->br_ops && bridge->br_ops->enable_show) + if (bridge->br_ops->enable_show) enable = bridge->br_ops->enable_show(bridge); return sprintf(buf, "%s\n", enable ? "enabled" : "disabled"); @@ -312,55 +315,69 @@ static struct attribute *fpga_bridge_attrs[] = { ATTRIBUTE_GROUPS(fpga_bridge); /** - * fpga_bridge_create - create and initialize a struct fpga_bridge - * @dev: FPGA bridge device from pdev + * __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 + * @owner: owner module containing the br_ops * - * 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 *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, struct module *owner) { struct fpga_bridge *bridge; int id, ret; + if (!br_ops) { + dev_err(parent, "Attempt to register without fpga_bridge_ops\n"); + return ERR_PTR(-EINVAL); + } + if (!name || !strlen(name)) { - dev_err(dev, "Attempt to register with no name!\n"); - return NULL; + dev_err(parent, "Attempt to register with no name!\n"); + 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->br_ops_owner = owner; bridge->priv = priv; - device_initialize(&bridge->dev); bridge->dev.groups = br_ops->groups; bridge->dev.class = fpga_bridge_class; - bridge->dev.parent = dev; - bridge->dev.of_node = dev->of_node; + bridge->dev.parent = parent; + bridge->dev.of_node = parent->of_node; bridge->dev.id = id; 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); + } + + of_platform_populate(bridge->dev.of_node, NULL, NULL, &bridge->dev); + return bridge; error_device: @@ -368,90 +385,9 @@ struct fpga_bridge *fpga_bridge_create(struct device *dev, const char *name, error_kfree: kfree(bridge); - return NULL; -} -EXPORT_SYMBOL_GPL(fpga_bridge_create); - -/** - * fpga_bridge_free - free a 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); -} - -/** - * devm_fpga_bridge_create - create and init a managed struct fpga_bridge - * @dev: 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 a 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. - * - * Return: struct fpga_bridge or NULL - */ -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 **ptr, *bridge; - - ptr = devres_alloc(devm_fpga_bridge_release, sizeof(*ptr), GFP_KERNEL); - if (!ptr) - return NULL; - - bridge = fpga_bridge_create(dev, name, br_ops, priv); - if (!bridge) { - devres_free(ptr); - } else { - *ptr = bridge; - devres_add(dev, ptr); - } - - return bridge; -} -EXPORT_SYMBOL_GPL(devm_fpga_bridge_create); - -/** - * fpga_bridge_register - register a 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 ERR_PTR(ret); } -EXPORT_SYMBOL_GPL(fpga_bridge_register); +EXPORT_SYMBOL_GPL(__fpga_bridge_register); /** * fpga_bridge_unregister - unregister a FPGA bridge @@ -466,7 +402,7 @@ void fpga_bridge_unregister(struct fpga_bridge *bridge) * If the low level driver provides a method for putting bridge into * a desired state upon unregister, do it. */ - if (bridge->br_ops && bridge->br_ops->fpga_bridge_remove) + if (bridge->br_ops->fpga_bridge_remove) bridge->br_ops->fpga_bridge_remove(bridge); device_unregister(&bridge->dev); @@ -475,6 +411,10 @@ 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 7d69af23056773136fa4611d0dd7d178ee2e4567..4a2bcb148d5dbf2d1c80065a32bb9f43c44d77f4 100644 --- a/drivers/fpga/xilinx-pr-decoupler.c +++ b/drivers/fpga/xilinx-pr-decoupler.c @@ -114,21 +114,16 @@ static int xlnx_pr_decoupler_probe(struct platform_device *pdev) clk_disable(priv->clk); - br = devm_fpga_bridge_create(&pdev->dev, "Xilinx PR Decoupler", + br = fpga_bridge_register(&pdev->dev, "Xilinx PR Decoupler", &xlnx_pr_decoupler_br_ops, priv); - if (!br) { - err = -ENOMEM; + if (IS_ERR(br)) { + err = PTR_ERR(br); + dev_err(&pdev->dev, "unable to register Xilinx PR Decoupler"); goto err_clk; } platform_set_drvdata(pdev, br); - err = fpga_bridge_register(br); - if (err) { - dev_err(&pdev->dev, "unable to register Xilinx PR Decoupler"); - goto err_clk; - } - return 0; err_clk: diff --git a/include/linux/fpga/fpga-bridge.h b/include/linux/fpga/fpga-bridge.h index 817600a32c935568fd9ffdbbcb13dd392b5ba3e2..36363207d9f13854a9fc81e4da303e85ef9a600a 100644 --- a/include/linux/fpga/fpga-bridge.h +++ b/include/linux/fpga/fpga-bridge.h @@ -22,12 +22,30 @@ 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 * @dev: FPGA bridge device * @mutex: enforces exclusive reference to bridge * @br_ops: pointer to struct of FPGA bridge ops + * @br_ops_owner: module containing the br_ops * @info: fpga image specific information * @node: FPGA bridge list node * @priv: low level driver private date @@ -37,6 +55,7 @@ struct fpga_bridge { struct device dev; struct mutex mutex; /* for exclusive reference to bridge */ const struct fpga_bridge_ops *br_ops; + struct module *br_ops_owner; struct fpga_image_info *info; struct list_head node; void *priv; @@ -62,15 +81,12 @@ 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); +#define fpga_bridge_register(parent, name, br_ops, priv) \ + __fpga_bridge_register(parent, name, br_ops, priv, THIS_MODULE) +struct fpga_bridge * +__fpga_bridge_register(struct device *parent, const char *name, + const struct fpga_bridge_ops *br_ops, void *priv, + struct module *owner); void fpga_bridge_unregister(struct fpga_bridge *br); -struct fpga_bridge -*devm_fpga_bridge_create(struct device *dev, const char *name, - const struct fpga_bridge_ops *br_ops, void *priv); - #endif /* _LINUX_FPGA_BRIDGE_H */