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 <sound/sdca.h>
9 #include "bus.h"
10 #include "sysfs_local.h"
11 
sdw_slave_release(struct device * dev)12 static void sdw_slave_release(struct device *dev)
13 {
14 	struct sdw_slave *slave = dev_to_sdw_dev(dev);
15 
16 	of_node_put(slave->dev.of_node);
17 	mutex_destroy(&slave->sdw_dev_lock);
18 	kfree(slave);
19 }
20 
21 const struct device_type sdw_slave_type = {
22 	.name =		"sdw_slave",
23 	.release =	sdw_slave_release,
24 	.uevent =	sdw_slave_uevent,
25 };
26 
sdw_slave_add(struct sdw_bus * bus,struct sdw_slave_id * id,struct fwnode_handle * fwnode)27 int sdw_slave_add(struct sdw_bus *bus,
28 		  struct sdw_slave_id *id, struct fwnode_handle *fwnode)
29 {
30 	struct sdw_slave *slave;
31 	int ret;
32 	int i;
33 
34 	slave = kzalloc(sizeof(*slave), GFP_KERNEL);
35 	if (!slave)
36 		return -ENOMEM;
37 
38 	/* Initialize data structure */
39 	memcpy(&slave->id, id, sizeof(*id));
40 	slave->dev.parent = bus->dev;
41 	slave->dev.fwnode = fwnode;
42 
43 	if (id->unique_id == SDW_IGNORED_UNIQUE_ID) {
44 		/* name shall be sdw:ctrl:link:mfg:part:class */
45 		dev_set_name(&slave->dev, "sdw:%01x:%01x:%04x:%04x:%02x",
46 			     bus->controller_id, bus->link_id, id->mfg_id, id->part_id,
47 			     id->class_id);
48 	} else {
49 		/* name shall be sdw:ctrl:link:mfg:part:class:unique */
50 		dev_set_name(&slave->dev, "sdw:%01x:%01x:%04x:%04x:%02x:%01x",
51 			     bus->controller_id, bus->link_id, id->mfg_id, id->part_id,
52 			     id->class_id, id->unique_id);
53 	}
54 
55 	slave->dev.bus = &sdw_bus_type;
56 	slave->dev.of_node = of_node_get(to_of_node(fwnode));
57 	slave->dev.type = &sdw_slave_type;
58 	slave->dev.groups = sdw_slave_status_attr_groups;
59 	slave->bus = bus;
60 	slave->status = SDW_SLAVE_UNATTACHED;
61 	init_completion(&slave->enumeration_complete);
62 	init_completion(&slave->initialization_complete);
63 	slave->dev_num = 0;
64 	slave->probed = false;
65 	slave->first_interrupt_done = false;
66 	mutex_init(&slave->sdw_dev_lock);
67 
68 	for (i = 0; i < SDW_MAX_PORTS; i++)
69 		init_completion(&slave->port_ready[i]);
70 
71 	mutex_lock(&bus->bus_lock);
72 	list_add_tail(&slave->node, &bus->slaves);
73 	mutex_unlock(&bus->bus_lock);
74 
75 	/*
76 	 * The Soundwire driver probe may optionally register SDCA
77 	 * sub-devices, one per Function. This means the information
78 	 * on the SDCA revision and the number/type of Functions need
79 	 * to be extracted from platform firmware before the SoundWire
80 	 * driver probe, and as a consequence before the SoundWire
81 	 * device_register() below.
82 	 */
83 	sdca_lookup_interface_revision(slave);
84 	sdca_lookup_functions(slave);
85 
86 	ret = device_register(&slave->dev);
87 	if (ret) {
88 		dev_err(bus->dev, "Failed to add slave: ret %d\n", ret);
89 
90 		/*
91 		 * On err, don't free but drop ref as this will be freed
92 		 * when release method is invoked.
93 		 */
94 		mutex_lock(&bus->bus_lock);
95 		list_del(&slave->node);
96 		mutex_unlock(&bus->bus_lock);
97 		put_device(&slave->dev);
98 
99 		return ret;
100 	}
101 	sdw_slave_debugfs_init(slave);
102 
103 	return ret;
104 }
105 EXPORT_SYMBOL(sdw_slave_add);
106 
107 #if IS_ENABLED(CONFIG_ACPI)
108 
find_slave(struct sdw_bus * bus,struct acpi_device * adev,struct sdw_slave_id * id)109 static bool find_slave(struct sdw_bus *bus,
110 		       struct acpi_device *adev,
111 		       struct sdw_slave_id *id)
112 {
113 	unsigned int link_id;
114 	u64 addr;
115 	int ret;
116 
117 	ret = acpi_get_local_u64_address(adev->handle, &addr);
118 	if (ret < 0)
119 		return false;
120 
121 	if (bus->ops->override_adr)
122 		addr = bus->ops->override_adr(bus, addr);
123 
124 	if (!addr)
125 		return false;
126 
127 	/* Extract link id from ADR, Bit 51 to 48 (included) */
128 	link_id = SDW_DISCO_LINK_ID(addr);
129 
130 	/* Check for link_id match */
131 	if (link_id != bus->link_id)
132 		return false;
133 
134 	sdw_extract_slave_id(bus, addr, id);
135 
136 	return true;
137 }
138 
139 struct sdw_acpi_child_walk_data {
140 	struct sdw_bus *bus;
141 	struct acpi_device *adev;
142 	struct sdw_slave_id id;
143 	bool ignore_unique_id;
144 };
145 
sdw_acpi_check_duplicate(struct acpi_device * adev,void * data)146 static int sdw_acpi_check_duplicate(struct acpi_device *adev, void *data)
147 {
148 	struct sdw_acpi_child_walk_data *cwd = data;
149 	struct sdw_bus *bus = cwd->bus;
150 	struct sdw_slave_id id;
151 
152 	if (adev == cwd->adev)
153 		return 0;
154 
155 	if (!find_slave(bus, adev, &id))
156 		return 0;
157 
158 	if (cwd->id.sdw_version != id.sdw_version || cwd->id.mfg_id != id.mfg_id ||
159 	    cwd->id.part_id != id.part_id || cwd->id.class_id != id.class_id)
160 		return 0;
161 
162 	if (cwd->id.unique_id != id.unique_id) {
163 		dev_dbg(bus->dev,
164 			"Valid 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,
166 			cwd->id.part_id);
167 		cwd->ignore_unique_id = false;
168 		return 0;
169 	}
170 
171 	dev_err(bus->dev,
172 		"Invalid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n",
173 		cwd->id.unique_id, id.unique_id, cwd->id.mfg_id, cwd->id.part_id);
174 	return -ENODEV;
175 }
176 
sdw_acpi_find_one(struct acpi_device * adev,void * data)177 static int sdw_acpi_find_one(struct acpi_device *adev, void *data)
178 {
179 	struct sdw_bus *bus = data;
180 	struct sdw_acpi_child_walk_data cwd = {
181 		.bus = bus,
182 		.adev = adev,
183 		.ignore_unique_id = true,
184 	};
185 	int ret;
186 
187 	if (!find_slave(bus, adev, &cwd.id))
188 		return 0;
189 
190 	/* Brute-force O(N^2) search for duplicates. */
191 	ret = acpi_dev_for_each_child(ACPI_COMPANION(bus->dev),
192 				      sdw_acpi_check_duplicate, &cwd);
193 	if (ret)
194 		return ret;
195 
196 	if (cwd.ignore_unique_id)
197 		cwd.id.unique_id = SDW_IGNORED_UNIQUE_ID;
198 
199 	/* Ignore errors and continue. */
200 	sdw_slave_add(bus, &cwd.id, acpi_fwnode_handle(adev));
201 	return 0;
202 }
203 
204 /*
205  * sdw_acpi_find_slaves() - Find Slave devices in Master ACPI node
206  * @bus: SDW bus instance
207  *
208  * Scans Master ACPI node for SDW child Slave devices and registers it.
209  */
sdw_acpi_find_slaves(struct sdw_bus * bus)210 int sdw_acpi_find_slaves(struct sdw_bus *bus)
211 {
212 	struct acpi_device *parent;
213 
214 	parent = ACPI_COMPANION(bus->dev);
215 	if (!parent) {
216 		dev_err(bus->dev, "Can't find parent for acpi bind\n");
217 		return -ENODEV;
218 	}
219 
220 	return acpi_dev_for_each_child(parent, sdw_acpi_find_one, bus);
221 }
222 
223 #endif
224 
225 /*
226  * sdw_of_find_slaves() - Find Slave devices in master device tree node
227  * @bus: SDW bus instance
228  *
229  * Scans Master DT node for SDW child Slave devices and registers it.
230  */
sdw_of_find_slaves(struct sdw_bus * bus)231 int sdw_of_find_slaves(struct sdw_bus *bus)
232 {
233 	struct device *dev = bus->dev;
234 	struct device_node *node;
235 
236 	for_each_child_of_node(bus->dev->of_node, node) {
237 		int link_id, ret, len;
238 		unsigned int sdw_version;
239 		const char *compat = NULL;
240 		struct sdw_slave_id id;
241 		const __be32 *addr;
242 
243 		compat = of_get_property(node, "compatible", NULL);
244 		if (!compat)
245 			continue;
246 
247 		ret = sscanf(compat, "sdw%01x%04hx%04hx%02hhx", &sdw_version,
248 			     &id.mfg_id, &id.part_id, &id.class_id);
249 
250 		if (ret != 4) {
251 			dev_err(dev, "Invalid compatible string found %s\n",
252 				compat);
253 			continue;
254 		}
255 
256 		addr = of_get_property(node, "reg", &len);
257 		if (!addr || (len < 2 * sizeof(u32))) {
258 			dev_err(dev, "Invalid Link and Instance ID\n");
259 			continue;
260 		}
261 
262 		link_id = be32_to_cpup(addr++);
263 		id.unique_id = be32_to_cpup(addr);
264 		id.sdw_version = sdw_version;
265 
266 		/* Check for link_id match */
267 		if (link_id != bus->link_id)
268 			continue;
269 
270 		sdw_slave_add(bus, &id, of_fwnode_handle(node));
271 	}
272 
273 	return 0;
274 }
275 
276 MODULE_IMPORT_NS("SND_SOC_SDCA");
277