// SPDX-License-Identifier: GPL-2.0 /* * Copyright (c) 2011-2017, The Linux Foundation */ #include <linux/kernel.h> #include <linux/errno.h> #include <linux/slab.h> #include <linux/init.h> #include <linux/idr.h> #include <linux/of.h> #include <linux/of_device.h> #include <linux/pm_runtime.h> #include <linux/slimbus.h> #include "slimbus.h" static DEFINE_IDA(ctrl_ida); static const struct slim_device_id *slim_match(const struct slim_device_id *id, const struct slim_device *sbdev) { while (id->manf_id != 0 || id->prod_code != 0) { if (id->manf_id == sbdev->e_addr.manf_id && id->prod_code == sbdev->e_addr.prod_code && id->dev_index == sbdev->e_addr.dev_index && id->instance == sbdev->e_addr.instance) return id; id++; } return NULL; } static int slim_device_match(struct device *dev, struct device_driver *drv) { struct slim_device *sbdev = to_slim_device(dev); struct slim_driver *sbdrv = to_slim_driver(drv); /* Attempt an OF style match first */ if (of_driver_match_device(dev, drv)) return 1; return !!slim_match(sbdrv->id_table, sbdev); } static void slim_device_update_status(struct slim_device *sbdev, enum slim_device_status status) { struct slim_driver *sbdrv; if (sbdev->status == status) return; sbdev->status = status; if (!sbdev->dev.driver) return; sbdrv = to_slim_driver(sbdev->dev.driver); if (sbdrv->device_status) sbdrv->device_status(sbdev, sbdev->status); } static int slim_device_probe(struct device *dev) { struct slim_device *sbdev = to_slim_device(dev); struct slim_driver *sbdrv = to_slim_driver(dev->driver); int ret; ret = sbdrv->probe(sbdev); if (ret) return ret; /* try getting the logical address after probe */ ret = slim_get_logical_addr(sbdev); if (!ret) { slim_device_update_status(sbdev, SLIM_DEVICE_STATUS_UP); } else { dev_err(&sbdev->dev, "Failed to get logical address\n"); ret = -EPROBE_DEFER; } return ret; } static int slim_device_remove(struct device *dev) { struct slim_device *sbdev = to_slim_device(dev); struct slim_driver *sbdrv; if (dev->driver) { sbdrv = to_slim_driver(dev->driver); if (sbdrv->remove) sbdrv->remove(sbdev); } return 0; } static int slim_device_uevent(struct device *dev, struct kobj_uevent_env *env) { struct slim_device *sbdev = to_slim_device(dev); return add_uevent_var(env, "MODALIAS=slim:%s", dev_name(&sbdev->dev)); } struct bus_type slimbus_bus = { .name = "slimbus", .match = slim_device_match, .probe = slim_device_probe, .remove = slim_device_remove, .uevent = slim_device_uevent, }; EXPORT_SYMBOL_GPL(slimbus_bus); /* * __slim_driver_register() - Client driver registration with SLIMbus * * @drv:Client driver to be associated with client-device. * @owner: owning module/driver * * This API will register the client driver with the SLIMbus * It is called from the driver's module-init function. */ int __slim_driver_register(struct slim_driver *drv, struct module *owner) { /* ID table and probe are mandatory */ if (!(drv->driver.of_match_table || drv->id_table) || !drv->probe) return -EINVAL; drv->driver.bus = &slimbus_bus; drv->driver.owner = owner; return driver_register(&drv->driver); } EXPORT_SYMBOL_GPL(__slim_driver_register); /* * slim_driver_unregister() - Undo effect of slim_driver_register * * @drv: Client driver to be unregistered */ void slim_driver_unregister(struct slim_driver *drv) { driver_unregister(&drv->driver); } EXPORT_SYMBOL_GPL(slim_driver_unregister); static void slim_dev_release(struct device *dev) { struct slim_device *sbdev = to_slim_device(dev); kfree(sbdev); } static int slim_add_device(struct slim_controller *ctrl, struct slim_device *sbdev, struct device_node *node) { sbdev->dev.bus = &slimbus_bus; sbdev->dev.parent = ctrl->dev; sbdev->dev.release = slim_dev_release; sbdev->dev.driver = NULL; sbdev->ctrl = ctrl; INIT_LIST_HEAD(&sbdev->stream_list); spin_lock_init(&sbdev->stream_list_lock); sbdev->dev.of_node = of_node_get(node); sbdev->dev.fwnode = of_fwnode_handle(node); dev_set_name(&sbdev->dev, "%x:%x:%x:%x", sbdev->e_addr.manf_id, sbdev->e_addr.prod_code, sbdev->e_addr.dev_index, sbdev->e_addr.instance); return device_register(&sbdev->dev); } static struct slim_device *slim_alloc_device(struct slim_controller *ctrl, struct slim_eaddr *eaddr, struct device_node *node) { struct slim_device *sbdev; int ret; sbdev = kzalloc(sizeof(*sbdev), GFP_KERNEL); if (!sbdev) return NULL; sbdev->e_addr = *eaddr; ret = slim_add_device(ctrl, sbdev, node); if (ret) { put_device(&sbdev->dev); return NULL; } return sbdev; } static void of_register_slim_devices(struct slim_controller *ctrl) { struct device *dev = ctrl->dev; struct device_node *node; if (!ctrl->dev->of_node) return; for_each_child_of_node(ctrl->dev->of_node, node) { struct slim_device *sbdev; struct slim_eaddr e_addr; const char *compat = NULL; int reg[2], ret; int manf_id, prod_code; compat = of_get_property(node, "compatible", NULL); if (!compat) continue; ret = sscanf(compat, "slim%x,%x", &manf_id, &prod_code); if (ret != 2) { dev_err(dev, "Manf ID & Product code not found %s\n", compat); continue; } ret = of_property_read_u32_array(node, "reg", reg, 2); if (ret) { dev_err(dev, "Device and Instance id not found:%d\n", ret); continue; } e_addr.dev_index = reg[0]; e_addr.instance = reg[1]; e_addr.manf_id = manf_id; e_addr.prod_code = prod_code; sbdev = slim_alloc_device(ctrl, &e_addr, node); if (!sbdev) continue; } } /* * slim_register_controller() - Controller bring-up and registration. * * @ctrl: Controller to be registered. * * A controller is registered with the framework using this API. * If devices on a controller were registered before controller, * this will make sure that they get probed when controller is up */ int slim_register_controller(struct slim_controller *ctrl) { int id; id = ida_simple_get(&ctrl_ida, 0, 0, GFP_KERNEL); if (id < 0) return id; ctrl->id = id; if (!ctrl->min_cg) ctrl->min_cg = SLIM_MIN_CLK_GEAR; if (!ctrl->max_cg) ctrl->max_cg = SLIM_MAX_CLK_GEAR; ida_init(&ctrl->laddr_ida); idr_init(&ctrl->tid_idr); mutex_init(&ctrl->lock); mutex_init(&ctrl->sched.m_reconf); init_completion(&ctrl->sched.pause_comp); spin_lock_init(&ctrl->txn_lock); dev_dbg(ctrl->dev, "Bus [%s] registered:dev:%p\n", ctrl->name, ctrl->dev); of_register_slim_devices(ctrl); return 0; } EXPORT_SYMBOL_GPL(slim_register_controller); /* slim_remove_device: Remove the effect of slim_add_device() */ static void slim_remove_device(struct slim_device *sbdev) { of_node_put(sbdev->dev.of_node); device_unregister(&sbdev->dev); } static int slim_ctrl_remove_device(struct device *dev, void *null) { slim_remove_device(to_slim_device(dev)); return 0; } /** * slim_unregister_controller() - Controller tear-down. * * @ctrl: Controller to tear-down. */ int slim_unregister_controller(struct slim_controller *ctrl) { /* Remove all clients */ device_for_each_child(ctrl->dev, NULL, slim_ctrl_remove_device); ida_simple_remove(&ctrl_ida, ctrl->id); return 0; } EXPORT_SYMBOL_GPL(slim_unregister_controller); /** * slim_report_absent() - Controller calls this function when a device * reports absent, OR when the device cannot be communicated with * * @sbdev: Device that cannot be reached, or sent report absent */ void slim_report_absent(struct slim_device *sbdev) { struct slim_controller *ctrl = sbdev->ctrl; if (!ctrl) return; /* invalidate logical addresses */ mutex_lock(&ctrl->lock); sbdev->is_laddr_valid = false; mutex_unlock(&ctrl->lock); if (!ctrl->get_laddr) ida_simple_remove(&ctrl->laddr_ida, sbdev->laddr); slim_device_update_status(sbdev, SLIM_DEVICE_STATUS_DOWN); } EXPORT_SYMBOL_GPL(slim_report_absent); static bool slim_eaddr_equal(struct slim_eaddr *a, struct slim_eaddr *b) { return (a->manf_id == b->manf_id && a->prod_code == b->prod_code && a->dev_index == b->dev_index && a->instance == b->instance); } static int slim_match_dev(struct device *dev, void *data) { struct slim_eaddr *e_addr = data; struct slim_device *sbdev = to_slim_device(dev); return slim_eaddr_equal(&sbdev->e_addr, e_addr); } static struct slim_device *find_slim_device(struct slim_controller *ctrl, struct slim_eaddr *eaddr) { struct slim_device *sbdev; struct device *dev; dev = device_find_child(ctrl->dev, eaddr, slim_match_dev); if (dev) { sbdev = to_slim_device(dev); return sbdev; } return NULL; } /** * slim_get_device() - get handle to a device. * * @ctrl: Controller on which this device will be added/queried * @e_addr: Enumeration address of the device to be queried * * Return: pointer to a device if it has already reported. Creates a new * device and returns pointer to it if the device has not yet enumerated. */ struct slim_device *slim_get_device(struct slim_controller *ctrl, struct slim_eaddr *e_addr) { struct slim_device *sbdev; sbdev = find_slim_device(ctrl, e_addr); if (!sbdev) { sbdev = slim_alloc_device(ctrl, e_addr, NULL); if (!sbdev) return ERR_PTR(-ENOMEM); } return sbdev; } EXPORT_SYMBOL_GPL(slim_get_device); static int of_slim_match_dev(struct device *dev, void *data) { struct device_node *np = data; struct slim_device *sbdev = to_slim_device(dev); return (sbdev->dev.of_node == np); } static struct slim_device *of_find_slim_device(struct slim_controller *ctrl, struct device_node *np) { struct slim_device *sbdev; struct device *dev; dev = device_find_child(ctrl->dev, np, of_slim_match_dev); if (dev) { sbdev = to_slim_device(dev); return sbdev; } return NULL; } /** * of_slim_get_device() - get handle to a device using dt node. * * @ctrl: Controller on which this device will be added/queried * @np: node pointer to device * * Return: pointer to a device if it has already reported. Creates a new * device and returns pointer to it if the device has not yet enumerated. */ struct slim_device *of_slim_get_device(struct slim_controller *ctrl, struct device_node *np) { return of_find_slim_device(ctrl, np); } EXPORT_SYMBOL_GPL(of_slim_get_device); static int slim_device_alloc_laddr(struct slim_device *sbdev, bool report_present) { struct slim_controller *ctrl = sbdev->ctrl; u8 laddr; int ret; mutex_lock(&ctrl->lock); if (ctrl->get_laddr) { ret = ctrl->get_laddr(ctrl, &sbdev->e_addr, &laddr); if (ret < 0) goto err; } else if (report_present) { ret = ida_simple_get(&ctrl->laddr_ida, 0, SLIM_LA_MANAGER - 1, GFP_KERNEL); if (ret < 0) goto err; laddr = ret; } else { ret = -EINVAL; goto err; } if (ctrl->set_laddr) { ret = ctrl->set_laddr(ctrl, &sbdev->e_addr, laddr); if (ret) { ret = -EINVAL; goto err; } } sbdev->laddr = laddr; sbdev->is_laddr_valid = true; mutex_unlock(&ctrl->lock); slim_device_update_status(sbdev, SLIM_DEVICE_STATUS_UP); dev_dbg(ctrl->dev, "setting slimbus l-addr:%x, ea:%x,%x,%x,%x\n", laddr, sbdev->e_addr.manf_id, sbdev->e_addr.prod_code, sbdev->e_addr.dev_index, sbdev->e_addr.instance); return 0; err: mutex_unlock(&ctrl->lock); return ret; } /** * slim_device_report_present() - Report enumerated device. * * @ctrl: Controller with which device is enumerated. * @e_addr: Enumeration address of the device. * @laddr: Return logical address (if valid flag is false) * * Called by controller in response to REPORT_PRESENT. Framework will assign * a logical address to this enumeration address. * Function returns -EXFULL to indicate that all logical addresses are already * taken. */ int slim_device_report_present(struct slim_controller *ctrl, struct slim_eaddr *e_addr, u8 *laddr) { struct slim_device *sbdev; int ret; ret = pm_runtime_get_sync(ctrl->dev); if (ctrl->sched.clk_state != SLIM_CLK_ACTIVE) { dev_err(ctrl->dev, "slim ctrl not active,state:%d, ret:%d\n", ctrl->sched.clk_state, ret); goto slimbus_not_active; } sbdev = slim_get_device(ctrl, e_addr); if (IS_ERR(sbdev)) return -ENODEV; if (sbdev->is_laddr_valid) { *laddr = sbdev->laddr; return 0; } ret = slim_device_alloc_laddr(sbdev, true); slimbus_not_active: pm_runtime_mark_last_busy(ctrl->dev); pm_runtime_put_autosuspend(ctrl->dev); return ret; } EXPORT_SYMBOL_GPL(slim_device_report_present); /** * slim_get_logical_addr() - get/allocate logical address of a SLIMbus device. * * @sbdev: client handle requesting the address. * * Return: zero if a logical address is valid or a new logical address * has been assigned. error code in case of error. */ int slim_get_logical_addr(struct slim_device *sbdev) { if (!sbdev->is_laddr_valid) return slim_device_alloc_laddr(sbdev, false); return 0; } EXPORT_SYMBOL_GPL(slim_get_logical_addr); static void __exit slimbus_exit(void) { bus_unregister(&slimbus_bus); } module_exit(slimbus_exit); static int __init slimbus_init(void) { return bus_register(&slimbus_bus); } postcore_initcall(slimbus_init); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("SLIMbus core");