1// SPDX-License-Identifier: GPL-2.0
2// Copyright(c) 2015-17 Intel Corporation.
3
4#include <linux/module.h>
5#include <linux/mod_devicetable.h>
6#include <linux/pm_domain.h>
7#include <linux/soundwire/sdw.h>
8#include <linux/soundwire/sdw_type.h>
9#include "bus.h"
10#include "irq.h"
11#include "sysfs_local.h"
12
13/**
14 * sdw_get_device_id - find the matching SoundWire device id
15 * @slave: SoundWire Slave Device
16 * @drv: SoundWire Slave Driver
17 *
18 * The match is done by comparing the mfg_id and part_id from the
19 * struct sdw_device_id.
20 */
21static const struct sdw_device_id *
22sdw_get_device_id(struct sdw_slave *slave, struct sdw_driver *drv)
23{
24 const struct sdw_device_id *id;
25
26 for (id = drv->id_table; id && id->mfg_id; id++)
27 if (slave->id.mfg_id == id->mfg_id &&
28 slave->id.part_id == id->part_id &&
29 (!id->sdw_version ||
30 slave->id.sdw_version == id->sdw_version) &&
31 (!id->class_id ||
32 slave->id.class_id == id->class_id))
33 return id;
34
35 return NULL;
36}
37
38static int sdw_bus_match(struct device *dev, struct device_driver *ddrv)
39{
40 struct sdw_slave *slave;
41 struct sdw_driver *drv;
42 int ret = 0;
43
44 if (is_sdw_slave(dev)) {
45 slave = dev_to_sdw_dev(dev);
46 drv = drv_to_sdw_driver(ddrv);
47
48 ret = !!sdw_get_device_id(slave, drv);
49 }
50 return ret;
51}
52
53int sdw_slave_modalias(const struct sdw_slave *slave, char *buf, size_t size)
54{
55 /* modalias is sdw:m<mfg_id>p<part_id>v<version>c<class_id> */
56
57 return snprintf(buf, size, fmt: "sdw:m%04Xp%04Xv%02Xc%02X\n",
58 slave->id.mfg_id, slave->id.part_id,
59 slave->id.sdw_version, slave->id.class_id);
60}
61
62int sdw_slave_uevent(const struct device *dev, struct kobj_uevent_env *env)
63{
64 const struct sdw_slave *slave = dev_to_sdw_dev(dev);
65 char modalias[32];
66
67 sdw_slave_modalias(slave, buf: modalias, size: sizeof(modalias));
68
69 if (add_uevent_var(env, format: "MODALIAS=%s", modalias))
70 return -ENOMEM;
71
72 return 0;
73}
74
75const struct bus_type sdw_bus_type = {
76 .name = "soundwire",
77 .match = sdw_bus_match,
78};
79EXPORT_SYMBOL_GPL(sdw_bus_type);
80
81static int sdw_drv_probe(struct device *dev)
82{
83 struct sdw_slave *slave = dev_to_sdw_dev(dev);
84 struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
85 const struct sdw_device_id *id;
86 const char *name;
87 int ret;
88
89 /*
90 * fw description is mandatory to bind
91 */
92 if (!dev->fwnode)
93 return -ENODEV;
94
95 if (!IS_ENABLED(CONFIG_ACPI) && !dev->of_node)
96 return -ENODEV;
97
98 id = sdw_get_device_id(slave, drv);
99 if (!id)
100 return -ENODEV;
101
102 /*
103 * attach to power domain but don't turn on (last arg)
104 */
105 ret = dev_pm_domain_attach(dev, power_on: false);
106 if (ret)
107 return ret;
108
109 ret = drv->probe(slave, id);
110 if (ret) {
111 name = drv->name;
112 if (!name)
113 name = drv->driver.name;
114
115 dev_err(dev, "Probe of %s failed: %d\n", name, ret);
116 dev_pm_domain_detach(dev, power_off: false);
117 return ret;
118 }
119
120 mutex_lock(&slave->sdw_dev_lock);
121
122 /* device is probed so let's read the properties now */
123 if (drv->ops && drv->ops->read_prop)
124 drv->ops->read_prop(slave);
125
126 if (slave->prop.use_domain_irq)
127 sdw_irq_create_mapping(slave);
128
129 /* init the sysfs as we have properties now */
130 ret = sdw_slave_sysfs_init(slave);
131 if (ret < 0)
132 dev_warn(dev, "Slave sysfs init failed:%d\n", ret);
133
134 /*
135 * Check for valid clk_stop_timeout, use DisCo worst case value of
136 * 300ms
137 *
138 * TODO: check the timeouts and driver removal case
139 */
140 if (slave->prop.clk_stop_timeout == 0)
141 slave->prop.clk_stop_timeout = 300;
142
143 slave->bus->clk_stop_timeout = max_t(u32, slave->bus->clk_stop_timeout,
144 slave->prop.clk_stop_timeout);
145
146 slave->probed = true;
147
148 /*
149 * if the probe happened after the bus was started, notify the codec driver
150 * of the current hardware status to e.g. start the initialization.
151 * Errors are only logged as warnings to avoid failing the probe.
152 */
153 if (drv->ops && drv->ops->update_status) {
154 ret = drv->ops->update_status(slave, slave->status);
155 if (ret < 0)
156 dev_warn(dev, "%s: update_status failed with status %d\n", __func__, ret);
157 }
158
159 mutex_unlock(lock: &slave->sdw_dev_lock);
160
161 dev_dbg(dev, "probe complete\n");
162
163 return 0;
164}
165
166static int sdw_drv_remove(struct device *dev)
167{
168 struct sdw_slave *slave = dev_to_sdw_dev(dev);
169 struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
170 int ret = 0;
171
172 mutex_lock(&slave->sdw_dev_lock);
173
174 slave->probed = false;
175
176 if (slave->prop.use_domain_irq)
177 sdw_irq_dispose_mapping(slave);
178
179 mutex_unlock(lock: &slave->sdw_dev_lock);
180
181 if (drv->remove)
182 ret = drv->remove(slave);
183
184 dev_pm_domain_detach(dev, power_off: false);
185
186 return ret;
187}
188
189static void sdw_drv_shutdown(struct device *dev)
190{
191 struct sdw_slave *slave = dev_to_sdw_dev(dev);
192 struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
193
194 if (drv->shutdown)
195 drv->shutdown(slave);
196}
197
198/**
199 * __sdw_register_driver() - register a SoundWire Slave driver
200 * @drv: driver to register
201 * @owner: owning module/driver
202 *
203 * Return: zero on success, else a negative error code.
204 */
205int __sdw_register_driver(struct sdw_driver *drv, struct module *owner)
206{
207 const char *name;
208
209 drv->driver.bus = &sdw_bus_type;
210
211 if (!drv->probe) {
212 name = drv->name;
213 if (!name)
214 name = drv->driver.name;
215
216 pr_err("driver %s didn't provide SDW probe routine\n", name);
217 return -EINVAL;
218 }
219
220 drv->driver.owner = owner;
221 drv->driver.probe = sdw_drv_probe;
222 drv->driver.remove = sdw_drv_remove;
223 drv->driver.shutdown = sdw_drv_shutdown;
224
225 return driver_register(drv: &drv->driver);
226}
227EXPORT_SYMBOL_GPL(__sdw_register_driver);
228
229/**
230 * sdw_unregister_driver() - unregisters the SoundWire Slave driver
231 * @drv: driver to unregister
232 */
233void sdw_unregister_driver(struct sdw_driver *drv)
234{
235 driver_unregister(drv: &drv->driver);
236}
237EXPORT_SYMBOL_GPL(sdw_unregister_driver);
238
239static int __init sdw_bus_init(void)
240{
241 sdw_debugfs_init();
242 return bus_register(bus: &sdw_bus_type);
243}
244
245static void __exit sdw_bus_exit(void)
246{
247 sdw_debugfs_exit();
248 bus_unregister(bus: &sdw_bus_type);
249}
250
251postcore_initcall(sdw_bus_init);
252module_exit(sdw_bus_exit);
253
254MODULE_DESCRIPTION("SoundWire bus");
255MODULE_LICENSE("GPL v2");
256

source code of linux/drivers/soundwire/bus_type.c