diff --git a/drivers/soundwire/Makefile b/drivers/soundwire/Makefile index d1281def7662..c875e434f8b3 100644 --- a/drivers/soundwire/Makefile +++ b/drivers/soundwire/Makefile @@ -3,5 +3,5 @@ # #Bus Objs -soundwire-bus-objs := bus_type.o +soundwire-bus-objs := bus_type.o bus.o slave.o obj-$(CONFIG_SOUNDWIRE_BUS) += soundwire-bus.o diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c new file mode 100644 index 000000000000..bc72c3d58bbf --- /dev/null +++ b/drivers/soundwire/bus.c @@ -0,0 +1,124 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +// Copyright(c) 2015-17 Intel Corporation. + +#include +#include +#include +#include "bus.h" + +/** + * sdw_add_bus_master() - add a bus Master instance + * @bus: bus instance + * + * Initializes the bus instance, read properties and create child + * devices. + */ +int sdw_add_bus_master(struct sdw_bus *bus) +{ + int ret; + + if (!bus->dev) { + pr_err("SoundWire bus has no device"); + return -ENODEV; + } + + mutex_init(&bus->bus_lock); + INIT_LIST_HEAD(&bus->slaves); + + /* + * Device numbers in SoundWire are 0 thru 15. Enumeration device + * number (0), Broadcast device number (15), Group numbers (12 and + * 13) and Master device number (14) are not used for assignment so + * mask these and other higher bits. + */ + + /* Set higher order bits */ + *bus->assigned = ~GENMASK(SDW_BROADCAST_DEV_NUM, SDW_ENUM_DEV_NUM); + + /* Set enumuration device number and broadcast device number */ + set_bit(SDW_ENUM_DEV_NUM, bus->assigned); + set_bit(SDW_BROADCAST_DEV_NUM, bus->assigned); + + /* Set group device numbers and master device number */ + set_bit(SDW_GROUP12_DEV_NUM, bus->assigned); + set_bit(SDW_GROUP13_DEV_NUM, bus->assigned); + set_bit(SDW_MASTER_DEV_NUM, bus->assigned); + + /* + * SDW is an enumerable bus, but devices can be powered off. So, + * they won't be able to report as present. + * + * Create Slave devices based on Slaves described in + * the respective firmware (ACPI/DT) + */ + if (IS_ENABLED(CONFIG_ACPI) && ACPI_HANDLE(bus->dev)) + ret = sdw_acpi_find_slaves(bus); + else + ret = -ENOTSUPP; /* No ACPI/DT so error out */ + + if (ret) { + dev_err(bus->dev, "Finding slaves failed:%d\n", ret); + return ret; + } + + return 0; +} +EXPORT_SYMBOL(sdw_add_bus_master); + +static int sdw_delete_slave(struct device *dev, void *data) +{ + struct sdw_slave *slave = dev_to_sdw_dev(dev); + struct sdw_bus *bus = slave->bus; + + mutex_lock(&bus->bus_lock); + + if (slave->dev_num) /* clear dev_num if assigned */ + clear_bit(slave->dev_num, bus->assigned); + + list_del_init(&slave->node); + mutex_unlock(&bus->bus_lock); + + device_unregister(dev); + return 0; +} + +/** + * sdw_delete_bus_master() - delete the bus master instance + * @bus: bus to be deleted + * + * Remove the instance, delete the child devices. + */ +void sdw_delete_bus_master(struct sdw_bus *bus) +{ + device_for_each_child(bus->dev, NULL, sdw_delete_slave); +} +EXPORT_SYMBOL(sdw_delete_bus_master); + +void sdw_extract_slave_id(struct sdw_bus *bus, + u64 addr, struct sdw_slave_id *id) +{ + dev_dbg(bus->dev, "SDW Slave Addr: %llx", addr); + + /* + * Spec definition + * Register Bit Contents + * DevId_0 [7:4] 47:44 sdw_version + * DevId_0 [3:0] 43:40 unique_id + * DevId_1 39:32 mfg_id [15:8] + * DevId_2 31:24 mfg_id [7:0] + * DevId_3 23:16 part_id [15:8] + * DevId_4 15:08 part_id [7:0] + * DevId_5 07:00 class_id + */ + id->sdw_version = (addr >> 44) & GENMASK(3, 0); + id->unique_id = (addr >> 40) & GENMASK(3, 0); + id->mfg_id = (addr >> 24) & GENMASK(15, 0); + id->part_id = (addr >> 8) & GENMASK(15, 0); + id->class_id = addr & GENMASK(7, 0); + + dev_dbg(bus->dev, + "SDW Slave class_id %x, part_id %x, mfg_id %x, unique_id %x, version %x", + id->class_id, id->part_id, id->mfg_id, + id->unique_id, id->sdw_version); + +} diff --git a/drivers/soundwire/bus.h b/drivers/soundwire/bus.h new file mode 100644 index 000000000000..a54921825ce0 --- /dev/null +++ b/drivers/soundwire/bus.h @@ -0,0 +1,19 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +// Copyright(c) 2015-17 Intel Corporation. + +#ifndef __SDW_BUS_H +#define __SDW_BUS_H + +#if IS_ENABLED(CONFIG_ACPI) +int sdw_acpi_find_slaves(struct sdw_bus *bus); +#else +static inline int sdw_acpi_find_slaves(struct sdw_bus *bus) +{ + return -ENOTSUPP; +} +#endif + +void sdw_extract_slave_id(struct sdw_bus *bus, + u64 addr, struct sdw_slave_id *id); + +#endif /* __SDW_BUS_H */ diff --git a/drivers/soundwire/slave.c b/drivers/soundwire/slave.c new file mode 100644 index 000000000000..ac103bd0c176 --- /dev/null +++ b/drivers/soundwire/slave.c @@ -0,0 +1,114 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +// Copyright(c) 2015-17 Intel Corporation. + +#include +#include +#include +#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 diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h index 869d7041d9fc..3bfa7f1e2b47 100644 --- a/include/linux/soundwire/sdw.h +++ b/include/linux/soundwire/sdw.h @@ -7,6 +7,21 @@ struct sdw_bus; struct sdw_slave; +/* SDW spec defines and enums, as defined by MIPI 1.1. Spec */ + +/* SDW Broadcast Device Number */ +#define SDW_BROADCAST_DEV_NUM 15 + +/* SDW Enumeration Device Number */ +#define SDW_ENUM_DEV_NUM 0 + +/* SDW Group Device Numbers */ +#define SDW_GROUP12_DEV_NUM 12 +#define SDW_GROUP13_DEV_NUM 13 + +/* SDW Master Device Number, not supported yet */ +#define SDW_MASTER_DEV_NUM 14 + #define SDW_MAX_DEVICES 11 /** @@ -105,4 +120,7 @@ struct sdw_bus { struct mutex bus_lock; }; +int sdw_add_bus_master(struct sdw_bus *bus); +void sdw_delete_bus_master(struct sdw_bus *bus); + #endif /* __SOUNDWIRE_H */