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-rw-r--r--drivers/soundwire/slave.c266
1 files changed, 266 insertions, 0 deletions
diff --git a/drivers/soundwire/slave.c b/drivers/soundwire/slave.c
new file mode 100644
index 000000000..c1c1a2ac2
--- /dev/null
+++ b/drivers/soundwire/slave.c
@@ -0,0 +1,266 @@
+// 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);
+
+ mutex_destroy(&slave->sdw_dev_lock);
+ 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:%01x:%04x:%04x:%02x",
+ 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:%01x:%04x:%04x:%02x:%01x",
+ 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;
+ slave->probed = false;
+ slave->first_interrupt_done = false;
+ mutex_init(&slave->sdw_dev_lock);
+
+ 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;
+}
+EXPORT_SYMBOL(sdw_slave_add);
+
+#if IS_ENABLED(CONFIG_ACPI)
+
+static bool find_slave(struct sdw_bus *bus,
+ struct acpi_device *adev,
+ struct sdw_slave_id *id)
+{
+ u64 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;
+ }
+
+ if (bus->ops->override_adr)
+ addr = bus->ops->override_adr(bus, addr);
+
+ if (!addr)
+ 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;
+}
+
+struct sdw_acpi_child_walk_data {
+ struct sdw_bus *bus;
+ struct acpi_device *adev;
+ struct sdw_slave_id id;
+ bool ignore_unique_id;
+};
+
+static int sdw_acpi_check_duplicate(struct acpi_device *adev, void *data)
+{
+ struct sdw_acpi_child_walk_data *cwd = data;
+ struct sdw_bus *bus = cwd->bus;
+ struct sdw_slave_id id;
+
+ if (adev == cwd->adev)
+ return 0;
+
+ if (!find_slave(bus, adev, &id))
+ return 0;
+
+ if (cwd->id.sdw_version != id.sdw_version || cwd->id.mfg_id != id.mfg_id ||
+ cwd->id.part_id != id.part_id || cwd->id.class_id != id.class_id)
+ return 0;
+
+ if (cwd->id.unique_id != id.unique_id) {
+ dev_dbg(bus->dev,
+ "Valid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n",
+ cwd->id.unique_id, id.unique_id, cwd->id.mfg_id,
+ cwd->id.part_id);
+ cwd->ignore_unique_id = false;
+ return 0;
+ }
+
+ dev_err(bus->dev,
+ "Invalid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n",
+ cwd->id.unique_id, id.unique_id, cwd->id.mfg_id, cwd->id.part_id);
+ return -ENODEV;
+}
+
+static int sdw_acpi_find_one(struct acpi_device *adev, void *data)
+{
+ struct sdw_bus *bus = data;
+ struct sdw_acpi_child_walk_data cwd = {
+ .bus = bus,
+ .adev = adev,
+ .ignore_unique_id = true,
+ };
+ int ret;
+
+ if (!find_slave(bus, adev, &cwd.id))
+ return 0;
+
+ /* Brute-force O(N^2) search for duplicates. */
+ ret = acpi_dev_for_each_child(ACPI_COMPANION(bus->dev),
+ sdw_acpi_check_duplicate, &cwd);
+ if (ret)
+ return ret;
+
+ if (cwd.ignore_unique_id)
+ cwd.id.unique_id = SDW_IGNORED_UNIQUE_ID;
+
+ /* Ignore errors and continue. */
+ sdw_slave_add(bus, &cwd.id, acpi_fwnode_handle(adev));
+ return 0;
+}
+
+/*
+ * 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 *parent;
+
+ parent = ACPI_COMPANION(bus->dev);
+ if (!parent) {
+ dev_err(bus->dev, "Can't find parent for acpi bind\n");
+ return -ENODEV;
+ }
+
+ return acpi_dev_for_each_child(parent, sdw_acpi_find_one, bus);
+}
+
+#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;
+}