diff options
Diffstat (limited to 'drivers/soundwire/slave.c')
| -rw-r--r-- | drivers/soundwire/slave.c | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/drivers/soundwire/slave.c b/drivers/soundwire/slave.c new file mode 100644 index 000000000..a08f4081c --- /dev/null +++ b/drivers/soundwire/slave.c @@ -0,0 +1,243 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +// Copyright(c) 2015-17 Intel Corporation. + +#include <linux/acpi.h> +#include <linux/of.h> +#include <linux/soundwire/sdw.h> +#include <linux/soundwire/sdw_type.h> +#include "bus.h" +#include "sysfs_local.h" + +static void sdw_slave_release(struct device *dev) +{ + struct sdw_slave *slave = dev_to_sdw_dev(dev); + + kfree(slave); +} + +struct device_type sdw_slave_type = { + .name = "sdw_slave", + .release = sdw_slave_release, + .uevent = sdw_slave_uevent, +}; + +int sdw_slave_add(struct sdw_bus *bus, + struct sdw_slave_id *id, struct fwnode_handle *fwnode) +{ + struct sdw_slave *slave; + int ret; + int i; + + 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; + + if (id->unique_id == SDW_IGNORED_UNIQUE_ID) { + /* name shall be sdw:link:mfg:part:class */ + dev_set_name(&slave->dev, "sdw:%x:%x:%x:%x", + bus->link_id, id->mfg_id, id->part_id, + id->class_id); + } else { + /* 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.bus = &sdw_bus_type; + slave->dev.of_node = of_node_get(to_of_node(fwnode)); + slave->dev.type = &sdw_slave_type; + slave->dev.groups = sdw_slave_status_attr_groups; + slave->bus = bus; + slave->status = SDW_SLAVE_UNATTACHED; + init_completion(&slave->enumeration_complete); + init_completion(&slave->initialization_complete); + slave->dev_num = 0; + init_completion(&slave->probe_complete); + slave->probed = false; + slave->first_interrupt_done = false; + + for (i = 0; i < SDW_MAX_PORTS; i++) + init_completion(&slave->port_ready[i]); + + 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; + } + sdw_slave_debugfs_init(slave); + + return ret; +} + +#if IS_ENABLED(CONFIG_ACPI) + +static bool find_slave(struct sdw_bus *bus, + struct acpi_device *adev, + struct sdw_slave_id *id) +{ + unsigned long long addr; + 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 false; + } + + /* Extract link id from ADR, Bit 51 to 48 (included) */ + link_id = SDW_DISCO_LINK_ID(addr); + + /* Check for link_id match */ + if (link_id != bus->link_id) + return false; + + sdw_extract_slave_id(bus, addr, id); + + return true; +} + +/* + * 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; + struct acpi_device *adev2, *parent2; + + 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) { + struct sdw_slave_id id; + struct sdw_slave_id id2; + bool ignore_unique_id = true; + + if (!find_slave(bus, adev, &id)) + continue; + + /* brute-force O(N^2) search for duplicates */ + parent2 = parent; + list_for_each_entry(adev2, &parent2->children, node) { + + if (adev == adev2) + continue; + + if (!find_slave(bus, adev2, &id2)) + continue; + + if (id.sdw_version != id2.sdw_version || + id.mfg_id != id2.mfg_id || + id.part_id != id2.part_id || + id.class_id != id2.class_id) + continue; + + if (id.unique_id != id2.unique_id) { + dev_dbg(bus->dev, + "Valid unique IDs %x %x for Slave mfg %x part %d\n", + id.unique_id, id2.unique_id, + id.mfg_id, id.part_id); + ignore_unique_id = false; + } else { + dev_err(bus->dev, + "Invalid unique IDs %x %x for Slave mfg %x part %d\n", + id.unique_id, id2.unique_id, + id.mfg_id, id.part_id); + return -ENODEV; + } + } + + if (ignore_unique_id) + id.unique_id = SDW_IGNORED_UNIQUE_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 + +/* + * sdw_of_find_slaves() - Find Slave devices in master device tree node + * @bus: SDW bus instance + * + * Scans Master DT node for SDW child Slave devices and registers it. + */ +int sdw_of_find_slaves(struct sdw_bus *bus) +{ + struct device *dev = bus->dev; + struct device_node *node; + + for_each_child_of_node(bus->dev->of_node, node) { + int link_id, ret, len; + unsigned int sdw_version; + const char *compat = NULL; + struct sdw_slave_id id; + const __be32 *addr; + + compat = of_get_property(node, "compatible", NULL); + if (!compat) + continue; + + ret = sscanf(compat, "sdw%01x%04hx%04hx%02hhx", &sdw_version, + &id.mfg_id, &id.part_id, &id.class_id); + + if (ret != 4) { + dev_err(dev, "Invalid compatible string found %s\n", + compat); + continue; + } + + addr = of_get_property(node, "reg", &len); + if (!addr || (len < 2 * sizeof(u32))) { + dev_err(dev, "Invalid Link and Instance ID\n"); + continue; + } + + link_id = be32_to_cpup(addr++); + id.unique_id = be32_to_cpup(addr); + id.sdw_version = sdw_version; + + /* Check for link_id match */ + if (link_id != bus->link_id) + continue; + + sdw_slave_add(bus, &id, of_fwnode_handle(node)); + } + + return 0; +} |