1// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
  2// Copyright(c) 2015-17 Intel Corporation.
  3
  4#include <linux/acpi.h>
  5#include <linux/of.h>
  6#include <linux/soundwire/sdw.h>
  7#include <linux/soundwire/sdw_type.h>
  8#include "bus.h"
  9#include "sysfs_local.h"
 10
 11static void sdw_slave_release(struct device *dev)
 12{
 13	struct sdw_slave *slave = dev_to_sdw_dev(dev);
 14
 15	mutex_destroy(&slave->sdw_dev_lock);
 16	kfree(slave);
 17}
 18
 19struct device_type sdw_slave_type = {
 20	.name =		"sdw_slave",
 21	.release =	sdw_slave_release,
 22	.uevent =	sdw_slave_uevent,
 23};
 24
 25int sdw_slave_add(struct sdw_bus *bus,
 26		  struct sdw_slave_id *id, struct fwnode_handle *fwnode)
 27{
 28	struct sdw_slave *slave;
 29	int ret;
 30	int i;
 31
 32	slave = kzalloc(sizeof(*slave), GFP_KERNEL);
 33	if (!slave)
 34		return -ENOMEM;
 35
 36	/* Initialize data structure */
 37	memcpy(&slave->id, id, sizeof(*id));
 38	slave->dev.parent = bus->dev;
 39	slave->dev.fwnode = fwnode;
 40
 41	if (id->unique_id == SDW_IGNORED_UNIQUE_ID) {
 42		/* name shall be sdw:ctrl:link:mfg:part:class */
 43		dev_set_name(&slave->dev, "sdw:%01x:%01x:%04x:%04x:%02x",
 44			     bus->controller_id, bus->link_id, id->mfg_id, id->part_id,
 45			     id->class_id);
 46	} else {
 47		/* name shall be sdw:ctrl:link:mfg:part:class:unique */
 48		dev_set_name(&slave->dev, "sdw:%01x:%01x:%04x:%04x:%02x:%01x",
 49			     bus->controller_id, bus->link_id, id->mfg_id, id->part_id,
 50			     id->class_id, id->unique_id);
 51	}
 52
 53	slave->dev.bus = &sdw_bus_type;
 54	slave->dev.of_node = of_node_get(to_of_node(fwnode));
 55	slave->dev.type = &sdw_slave_type;
 56	slave->dev.groups = sdw_slave_status_attr_groups;
 57	slave->bus = bus;
 58	slave->status = SDW_SLAVE_UNATTACHED;
 59	init_completion(&slave->enumeration_complete);
 60	init_completion(&slave->initialization_complete);
 61	slave->dev_num = 0;
 62	slave->probed = false;
 63	slave->first_interrupt_done = false;
 64	mutex_init(&slave->sdw_dev_lock);
 65
 66	for (i = 0; i < SDW_MAX_PORTS; i++)
 67		init_completion(&slave->port_ready[i]);
 68
 69	mutex_lock(&bus->bus_lock);
 70	list_add_tail(&slave->node, &bus->slaves);
 71	mutex_unlock(&bus->bus_lock);
 72
 73	ret = device_register(&slave->dev);
 74	if (ret) {
 75		dev_err(bus->dev, "Failed to add slave: ret %d\n", ret);
 76
 77		/*
 78		 * On err, don't free but drop ref as this will be freed
 79		 * when release method is invoked.
 80		 */
 81		mutex_lock(&bus->bus_lock);
 82		list_del(&slave->node);
 83		mutex_unlock(&bus->bus_lock);
 84		put_device(&slave->dev);
 85
 86		return ret;
 87	}
 88	sdw_slave_debugfs_init(slave);
 89
 90	return ret;
 91}
 92EXPORT_SYMBOL(sdw_slave_add);
 93
 94#if IS_ENABLED(CONFIG_ACPI)
 95
 96static bool find_slave(struct sdw_bus *bus,
 97		       struct acpi_device *adev,
 98		       struct sdw_slave_id *id)
 99{
100	u64 addr;
101	unsigned int link_id;
102	acpi_status status;
103
104	status = acpi_evaluate_integer(adev->handle,
105				       METHOD_NAME__ADR, NULL, &addr);
106
107	if (ACPI_FAILURE(status)) {
108		dev_err(bus->dev, "_ADR resolution failed: %x\n",
109			status);
110		return false;
111	}
112
113	if (bus->ops->override_adr)
114		addr = bus->ops->override_adr(bus, addr);
115
116	if (!addr)
117		return false;
118
119	/* Extract link id from ADR, Bit 51 to 48 (included) */
120	link_id = SDW_DISCO_LINK_ID(addr);
121
122	/* Check for link_id match */
123	if (link_id != bus->link_id)
124		return false;
125
126	sdw_extract_slave_id(bus, addr, id);
127
128	return true;
129}
130
131struct sdw_acpi_child_walk_data {
132	struct sdw_bus *bus;
133	struct acpi_device *adev;
134	struct sdw_slave_id id;
135	bool ignore_unique_id;
136};
137
138static int sdw_acpi_check_duplicate(struct acpi_device *adev, void *data)
139{
140	struct sdw_acpi_child_walk_data *cwd = data;
141	struct sdw_bus *bus = cwd->bus;
142	struct sdw_slave_id id;
143
144	if (adev == cwd->adev)
145		return 0;
146
147	if (!find_slave(bus, adev, &id))
148		return 0;
149
150	if (cwd->id.sdw_version != id.sdw_version || cwd->id.mfg_id != id.mfg_id ||
151	    cwd->id.part_id != id.part_id || cwd->id.class_id != id.class_id)
152		return 0;
153
154	if (cwd->id.unique_id != id.unique_id) {
155		dev_dbg(bus->dev,
156			"Valid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n",
157			cwd->id.unique_id, id.unique_id, cwd->id.mfg_id,
158			cwd->id.part_id);
159		cwd->ignore_unique_id = false;
160		return 0;
161	}
162
163	dev_err(bus->dev,
164		"Invalid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n",
165		cwd->id.unique_id, id.unique_id, cwd->id.mfg_id, cwd->id.part_id);
166	return -ENODEV;
167}
168
169static int sdw_acpi_find_one(struct acpi_device *adev, void *data)
170{
171	struct sdw_bus *bus = data;
172	struct sdw_acpi_child_walk_data cwd = {
173		.bus = bus,
174		.adev = adev,
175		.ignore_unique_id = true,
176	};
177	int ret;
178
179	if (!find_slave(bus, adev, &cwd.id))
180		return 0;
181
182	/* Brute-force O(N^2) search for duplicates. */
183	ret = acpi_dev_for_each_child(ACPI_COMPANION(bus->dev),
184				      sdw_acpi_check_duplicate, &cwd);
185	if (ret)
186		return ret;
187
188	if (cwd.ignore_unique_id)
189		cwd.id.unique_id = SDW_IGNORED_UNIQUE_ID;
190
191	/* Ignore errors and continue. */
192	sdw_slave_add(bus, &cwd.id, acpi_fwnode_handle(adev));
193	return 0;
194}
195
196/*
197 * sdw_acpi_find_slaves() - Find Slave devices in Master ACPI node
198 * @bus: SDW bus instance
199 *
200 * Scans Master ACPI node for SDW child Slave devices and registers it.
201 */
202int sdw_acpi_find_slaves(struct sdw_bus *bus)
203{
204	struct acpi_device *parent;
205
206	parent = ACPI_COMPANION(bus->dev);
207	if (!parent) {
208		dev_err(bus->dev, "Can't find parent for acpi bind\n");
209		return -ENODEV;
210	}
211
212	return acpi_dev_for_each_child(parent, sdw_acpi_find_one, bus);
213}
214
215#endif
216
217/*
218 * sdw_of_find_slaves() - Find Slave devices in master device tree node
219 * @bus: SDW bus instance
220 *
221 * Scans Master DT node for SDW child Slave devices and registers it.
222 */
223int sdw_of_find_slaves(struct sdw_bus *bus)
224{
225	struct device *dev = bus->dev;
226	struct device_node *node;
227
228	for_each_child_of_node(bus->dev->of_node, node) {
229		int link_id, ret, len;
230		unsigned int sdw_version;
231		const char *compat = NULL;
232		struct sdw_slave_id id;
233		const __be32 *addr;
234
235		compat = of_get_property(node, "compatible", NULL);
236		if (!compat)
237			continue;
238
239		ret = sscanf(compat, "sdw%01x%04hx%04hx%02hhx", &sdw_version,
240			     &id.mfg_id, &id.part_id, &id.class_id);
241
242		if (ret != 4) {
243			dev_err(dev, "Invalid compatible string found %s\n",
244				compat);
245			continue;
246		}
247
248		addr = of_get_property(node, "reg", &len);
249		if (!addr || (len < 2 * sizeof(u32))) {
250			dev_err(dev, "Invalid Link and Instance ID\n");
251			continue;
252		}
253
254		link_id = be32_to_cpup(addr++);
255		id.unique_id = be32_to_cpup(addr);
256		id.sdw_version = sdw_version;
257
258		/* Check for link_id match */
259		if (link_id != bus->link_id)
260			continue;
261
262		sdw_slave_add(bus, &id, of_fwnode_handle(node));
263	}
264
265	return 0;
266}