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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/soundwire/slave.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/soundwire/slave.c')
-rw-r--r-- | drivers/soundwire/slave.c | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/drivers/soundwire/slave.c b/drivers/soundwire/slave.c new file mode 100644 index 000000000..ac103bd0c --- /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 <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 |