From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- drivers/fpga/fpga-bridge.c | 441 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 441 insertions(+) create mode 100644 drivers/fpga/fpga-bridge.c (limited to 'drivers/fpga/fpga-bridge.c') diff --git a/drivers/fpga/fpga-bridge.c b/drivers/fpga/fpga-bridge.c new file mode 100644 index 0000000000..a024be2b84 --- /dev/null +++ b/drivers/fpga/fpga-bridge.c @@ -0,0 +1,441 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * FPGA Bridge Framework Driver + * + * Copyright (C) 2013-2016 Altera Corporation, All Rights Reserved. + * Copyright (C) 2017 Intel Corporation + */ +#include +#include +#include +#include +#include +#include +#include + +static DEFINE_IDA(fpga_bridge_ida); +static const struct class fpga_bridge_class; + +/* Lock for adding/removing bridges to linked lists*/ +static DEFINE_SPINLOCK(bridge_list_lock); + +/** + * fpga_bridge_enable - Enable transactions on the bridge + * + * @bridge: FPGA bridge + * + * Return: 0 for success, error code otherwise. + */ +int fpga_bridge_enable(struct fpga_bridge *bridge) +{ + dev_dbg(&bridge->dev, "enable\n"); + + if (bridge->br_ops && bridge->br_ops->enable_set) + return bridge->br_ops->enable_set(bridge, 1); + + return 0; +} +EXPORT_SYMBOL_GPL(fpga_bridge_enable); + +/** + * fpga_bridge_disable - Disable transactions on the bridge + * + * @bridge: FPGA bridge + * + * Return: 0 for success, error code otherwise. + */ +int fpga_bridge_disable(struct fpga_bridge *bridge) +{ + dev_dbg(&bridge->dev, "disable\n"); + + if (bridge->br_ops && 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, + struct fpga_image_info *info) +{ + struct fpga_bridge *bridge; + int ret = -ENODEV; + + bridge = to_fpga_bridge(dev); + + bridge->info = info; + + if (!mutex_trylock(&bridge->mutex)) { + ret = -EBUSY; + goto err_dev; + } + + if (!try_module_get(dev->parent->driver->owner)) + goto err_ll_mod; + + dev_dbg(&bridge->dev, "get\n"); + + return bridge; + +err_ll_mod: + mutex_unlock(&bridge->mutex); +err_dev: + put_device(dev); + return ERR_PTR(ret); +} + +/** + * of_fpga_bridge_get - get an exclusive reference to an fpga bridge + * + * @np: node pointer of an FPGA bridge. + * @info: fpga image specific information. + * + * Return: + * * fpga_bridge struct pointer if successful. + * * -EBUSY if someone already has a reference to the bridge. + * * -ENODEV if @np is not an FPGA Bridge or can't take parent driver refcount. + */ +struct fpga_bridge *of_fpga_bridge_get(struct device_node *np, + struct fpga_image_info *info) +{ + struct device *dev; + + dev = class_find_device_by_of_node(&fpga_bridge_class, np); + if (!dev) + return ERR_PTR(-ENODEV); + + return __fpga_bridge_get(dev, info); +} +EXPORT_SYMBOL_GPL(of_fpga_bridge_get); + +static int fpga_bridge_dev_match(struct device *dev, const void *data) +{ + return dev->parent == data; +} + +/** + * fpga_bridge_get - get an exclusive reference to an fpga bridge + * @dev: parent device that fpga bridge was registered with + * @info: fpga image specific information + * + * Given a device, get an exclusive reference to an fpga bridge. + * + * Return: fpga bridge struct or IS_ERR() condition containing error code. + */ +struct fpga_bridge *fpga_bridge_get(struct device *dev, + struct fpga_image_info *info) +{ + struct device *bridge_dev; + + bridge_dev = class_find_device(&fpga_bridge_class, NULL, dev, + fpga_bridge_dev_match); + if (!bridge_dev) + return ERR_PTR(-ENODEV); + + return __fpga_bridge_get(bridge_dev, info); +} +EXPORT_SYMBOL_GPL(fpga_bridge_get); + +/** + * fpga_bridge_put - release a reference to a bridge + * + * @bridge: FPGA bridge + */ +void fpga_bridge_put(struct fpga_bridge *bridge) +{ + dev_dbg(&bridge->dev, "put\n"); + + bridge->info = NULL; + module_put(bridge->dev.parent->driver->owner); + mutex_unlock(&bridge->mutex); + put_device(&bridge->dev); +} +EXPORT_SYMBOL_GPL(fpga_bridge_put); + +/** + * fpga_bridges_enable - enable bridges in a list + * @bridge_list: list of FPGA bridges + * + * Enable each bridge in the list. If list is empty, do nothing. + * + * Return: 0 for success or empty bridge list or an error code otherwise. + */ +int fpga_bridges_enable(struct list_head *bridge_list) +{ + struct fpga_bridge *bridge; + int ret; + + list_for_each_entry(bridge, bridge_list, node) { + ret = fpga_bridge_enable(bridge); + if (ret) + return ret; + } + + return 0; +} +EXPORT_SYMBOL_GPL(fpga_bridges_enable); + +/** + * fpga_bridges_disable - disable bridges in a list + * + * @bridge_list: list of FPGA bridges + * + * Disable each bridge in the list. If list is empty, do nothing. + * + * Return: 0 for success or empty bridge list or an error code otherwise. + */ +int fpga_bridges_disable(struct list_head *bridge_list) +{ + struct fpga_bridge *bridge; + int ret; + + list_for_each_entry(bridge, bridge_list, node) { + ret = fpga_bridge_disable(bridge); + if (ret) + return ret; + } + + return 0; +} +EXPORT_SYMBOL_GPL(fpga_bridges_disable); + +/** + * fpga_bridges_put - put bridges + * + * @bridge_list: list of FPGA bridges + * + * For each bridge in the list, put the bridge and remove it from the list. + * If list is empty, do nothing. + */ +void fpga_bridges_put(struct list_head *bridge_list) +{ + struct fpga_bridge *bridge, *next; + unsigned long flags; + + list_for_each_entry_safe(bridge, next, bridge_list, node) { + fpga_bridge_put(bridge); + + spin_lock_irqsave(&bridge_list_lock, flags); + list_del(&bridge->node); + spin_unlock_irqrestore(&bridge_list_lock, flags); + } +} +EXPORT_SYMBOL_GPL(fpga_bridges_put); + +/** + * of_fpga_bridge_get_to_list - get a bridge, add it to a list + * + * @np: node pointer of an FPGA bridge + * @info: fpga image specific information + * @bridge_list: list of FPGA bridges + * + * Get an exclusive reference to the bridge and it to the list. + * + * Return: 0 for success, error code from of_fpga_bridge_get() otherwise. + */ +int of_fpga_bridge_get_to_list(struct device_node *np, + struct fpga_image_info *info, + struct list_head *bridge_list) +{ + struct fpga_bridge *bridge; + unsigned long flags; + + bridge = of_fpga_bridge_get(np, info); + if (IS_ERR(bridge)) + return PTR_ERR(bridge); + + spin_lock_irqsave(&bridge_list_lock, flags); + list_add(&bridge->node, bridge_list); + spin_unlock_irqrestore(&bridge_list_lock, flags); + + return 0; +} +EXPORT_SYMBOL_GPL(of_fpga_bridge_get_to_list); + +/** + * fpga_bridge_get_to_list - given device, get a bridge, add it to a list + * + * @dev: FPGA bridge device + * @info: fpga image specific information + * @bridge_list: list of FPGA bridges + * + * Get an exclusive reference to the bridge and it to the list. + * + * Return: 0 for success, error code from fpga_bridge_get() otherwise. + */ +int fpga_bridge_get_to_list(struct device *dev, + struct fpga_image_info *info, + struct list_head *bridge_list) +{ + struct fpga_bridge *bridge; + unsigned long flags; + + bridge = fpga_bridge_get(dev, info); + if (IS_ERR(bridge)) + return PTR_ERR(bridge); + + spin_lock_irqsave(&bridge_list_lock, flags); + list_add(&bridge->node, bridge_list); + spin_unlock_irqrestore(&bridge_list_lock, flags); + + return 0; +} +EXPORT_SYMBOL_GPL(fpga_bridge_get_to_list); + +static ssize_t name_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct fpga_bridge *bridge = to_fpga_bridge(dev); + + return sprintf(buf, "%s\n", bridge->name); +} + +static ssize_t state_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct fpga_bridge *bridge = to_fpga_bridge(dev); + int state = 1; + + if (bridge->br_ops && bridge->br_ops->enable_show) { + state = bridge->br_ops->enable_show(bridge); + if (state < 0) + return state; + } + + return sysfs_emit(buf, "%s\n", state ? "enabled" : "disabled"); +} + +static DEVICE_ATTR_RO(name); +static DEVICE_ATTR_RO(state); + +static struct attribute *fpga_bridge_attrs[] = { + &dev_attr_name.attr, + &dev_attr_state.attr, + NULL, +}; +ATTRIBUTE_GROUPS(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 + * + * Return: struct fpga_bridge pointer or ERR_PTR() + */ +struct fpga_bridge * +fpga_bridge_register(struct device *parent, const char *name, + const struct fpga_bridge_ops *br_ops, + void *priv) +{ + 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(parent, "Attempt to register with no name!\n"); + return ERR_PTR(-EINVAL); + } + + bridge = kzalloc(sizeof(*bridge), GFP_KERNEL); + if (!bridge) + return ERR_PTR(-ENOMEM); + + id = ida_alloc(&fpga_bridge_ida, GFP_KERNEL); + 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->dev.groups = br_ops->groups; + bridge->dev.class = &fpga_bridge_class; + 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: + ida_free(&fpga_bridge_ida, id); +error_kfree: + kfree(bridge); + + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(fpga_bridge_register); + +/** + * fpga_bridge_unregister - unregister an FPGA bridge + * + * @bridge: FPGA bridge struct + * + * This function is intended for use in an FPGA bridge driver's remove function. + */ +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) + bridge->br_ops->fpga_bridge_remove(bridge); + + device_unregister(&bridge->dev); +} +EXPORT_SYMBOL_GPL(fpga_bridge_unregister); + +static void fpga_bridge_dev_release(struct device *dev) +{ + struct fpga_bridge *bridge = to_fpga_bridge(dev); + + ida_free(&fpga_bridge_ida, bridge->dev.id); + kfree(bridge); +} + +static const struct class fpga_bridge_class = { + .name = "fpga_bridge", + .dev_groups = fpga_bridge_groups, + .dev_release = fpga_bridge_dev_release, +}; + +static int __init fpga_bridge_dev_init(void) +{ + return class_register(&fpga_bridge_class); +} + +static void __exit fpga_bridge_dev_exit(void) +{ + class_unregister(&fpga_bridge_class); + ida_destroy(&fpga_bridge_ida); +} + +MODULE_DESCRIPTION("FPGA Bridge Driver"); +MODULE_AUTHOR("Alan Tull "); +MODULE_LICENSE("GPL v2"); + +subsys_initcall(fpga_bridge_dev_init); +module_exit(fpga_bridge_dev_exit); -- cgit v1.2.3