// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) // Copyright(c) 2015-17 Intel Corporation. #include <linux/acpi.h> #include <linux/soundwire/sdw.h> #include <linux/soundwire/sdw_type.h> #include "bus.h" static void sdw_slave_release(struct device *dev) { struct sdw_slave *slave = dev_to_sdw_dev(dev); kfree(slave); } static int sdw_slave_add(struct sdw_bus *bus, struct sdw_slave_id *id, struct fwnode_handle *fwnode) { struct sdw_slave *slave; int ret; slave = kzalloc(sizeof(*slave), GFP_KERNEL); if (!slave) return -ENOMEM; /* Initialize data structure */ memcpy(&slave->id, id, sizeof(*id)); slave->dev.parent = bus->dev; slave->dev.fwnode = fwnode; /* name shall be sdw:link:mfg:part:class:unique */ dev_set_name(&slave->dev, "sdw:%x:%x:%x:%x:%x", bus->link_id, id->mfg_id, id->part_id, id->class_id, id->unique_id); slave->dev.release = sdw_slave_release; slave->dev.bus = &sdw_bus_type; slave->bus = bus; slave->status = SDW_SLAVE_UNATTACHED; slave->dev_num = 0; mutex_lock(&bus->bus_lock); list_add_tail(&slave->node, &bus->slaves); mutex_unlock(&bus->bus_lock); ret = device_register(&slave->dev); if (ret) { dev_err(bus->dev, "Failed to add slave: ret %d\n", ret); /* * On err, don't free but drop ref as this will be freed * when release method is invoked. */ mutex_lock(&bus->bus_lock); list_del(&slave->node); mutex_unlock(&bus->bus_lock); put_device(&slave->dev); } return ret; } #if IS_ENABLED(CONFIG_ACPI) /* * sdw_acpi_find_slaves() - Find Slave devices in Master ACPI node * @bus: SDW bus instance * * Scans Master ACPI node for SDW child Slave devices and registers it. */ int sdw_acpi_find_slaves(struct sdw_bus *bus) { struct acpi_device *adev, *parent; parent = ACPI_COMPANION(bus->dev); if (!parent) { dev_err(bus->dev, "Can't find parent for acpi bind\n"); return -ENODEV; } list_for_each_entry(adev, &parent->children, node) { unsigned long long addr; struct sdw_slave_id id; unsigned int link_id; acpi_status status; status = acpi_evaluate_integer(adev->handle, METHOD_NAME__ADR, NULL, &addr); if (ACPI_FAILURE(status)) { dev_err(bus->dev, "_ADR resolution failed: %x\n", status); return status; } /* Extract link id from ADR, Bit 51 to 48 (included) */ link_id = (addr >> 48) & GENMASK(3, 0); /* Check for link_id match */ if (link_id != bus->link_id) continue; sdw_extract_slave_id(bus, addr, &id); /* * don't error check for sdw_slave_add as we want to continue * adding Slaves */ sdw_slave_add(bus, &id, acpi_fwnode_handle(adev)); } return 0; } #endif