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 */ 21 static const struct sdw_device_id * 22 sdw_get_device_id(struct sdw_slave *slave, const 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 38 static int sdw_bus_match(struct device *dev, const struct device_driver *ddrv) 39 { 40 struct sdw_slave *slave; 41 const 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 53 int 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, "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 62 int 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, modalias, sizeof(modalias)); 68 69 if (add_uevent_var(env, "MODALIAS=%s", modalias)) 70 return -ENOMEM; 71 72 return 0; 73 } 74 75 const struct bus_type sdw_bus_type = { 76 .name = "soundwire", 77 .match = sdw_bus_match, 78 }; 79 EXPORT_SYMBOL_GPL(sdw_bus_type); 80 81 static 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 int ret; 87 88 /* 89 * fw description is mandatory to bind 90 */ 91 if (!dev->fwnode) 92 return -ENODEV; 93 94 if (!IS_ENABLED(CONFIG_ACPI) && !dev->of_node) 95 return -ENODEV; 96 97 id = sdw_get_device_id(slave, drv); 98 if (!id) 99 return -ENODEV; 100 101 /* 102 * attach to power domain but don't turn on (last arg) 103 */ 104 ret = dev_pm_domain_attach(dev, false); 105 if (ret) 106 return ret; 107 108 ret = drv->probe(slave, id); 109 if (ret) { 110 dev_pm_domain_detach(dev, false); 111 return ret; 112 } 113 114 mutex_lock(&slave->sdw_dev_lock); 115 116 /* device is probed so let's read the properties now */ 117 if (drv->ops && drv->ops->read_prop) 118 drv->ops->read_prop(slave); 119 120 if (slave->prop.use_domain_irq) 121 sdw_irq_create_mapping(slave); 122 123 /* init the dynamic sysfs attributes we need */ 124 ret = sdw_slave_sysfs_dpn_init(slave); 125 if (ret < 0) 126 dev_warn(dev, "failed to initialise sysfs: %d\n", ret); 127 128 /* 129 * Check for valid clk_stop_timeout, use DisCo worst case value of 130 * 300ms 131 * 132 * TODO: check the timeouts and driver removal case 133 */ 134 if (slave->prop.clk_stop_timeout == 0) 135 slave->prop.clk_stop_timeout = 300; 136 137 slave->bus->clk_stop_timeout = max_t(u32, slave->bus->clk_stop_timeout, 138 slave->prop.clk_stop_timeout); 139 140 slave->probed = true; 141 142 /* 143 * if the probe happened after the bus was started, notify the codec driver 144 * of the current hardware status to e.g. start the initialization. 145 * Errors are only logged as warnings to avoid failing the probe. 146 */ 147 if (drv->ops && drv->ops->update_status) { 148 ret = drv->ops->update_status(slave, slave->status); 149 if (ret < 0) 150 dev_warn(dev, "failed to update status at probe: %d\n", ret); 151 } 152 153 mutex_unlock(&slave->sdw_dev_lock); 154 155 dev_dbg(dev, "probe complete\n"); 156 157 return 0; 158 } 159 160 static int sdw_drv_remove(struct device *dev) 161 { 162 struct sdw_slave *slave = dev_to_sdw_dev(dev); 163 struct sdw_driver *drv = drv_to_sdw_driver(dev->driver); 164 int ret = 0; 165 166 mutex_lock(&slave->sdw_dev_lock); 167 168 slave->probed = false; 169 170 mutex_unlock(&slave->sdw_dev_lock); 171 172 if (drv->remove) 173 ret = drv->remove(slave); 174 175 dev_pm_domain_detach(dev, false); 176 177 return ret; 178 } 179 180 static void sdw_drv_shutdown(struct device *dev) 181 { 182 struct sdw_slave *slave = dev_to_sdw_dev(dev); 183 struct sdw_driver *drv = drv_to_sdw_driver(dev->driver); 184 185 if (drv->shutdown) 186 drv->shutdown(slave); 187 } 188 189 /** 190 * __sdw_register_driver() - register a SoundWire Slave driver 191 * @drv: driver to register 192 * @owner: owning module/driver 193 * 194 * Return: zero on success, else a negative error code. 195 */ 196 int __sdw_register_driver(struct sdw_driver *drv, struct module *owner) 197 { 198 drv->driver.bus = &sdw_bus_type; 199 200 if (!drv->probe) { 201 pr_err("driver %s didn't provide SDW probe routine\n", 202 drv->driver.name); 203 return -EINVAL; 204 } 205 206 drv->driver.owner = owner; 207 drv->driver.probe = sdw_drv_probe; 208 drv->driver.remove = sdw_drv_remove; 209 drv->driver.shutdown = sdw_drv_shutdown; 210 drv->driver.dev_groups = sdw_attr_groups; 211 212 return driver_register(&drv->driver); 213 } 214 EXPORT_SYMBOL_GPL(__sdw_register_driver); 215 216 /** 217 * sdw_unregister_driver() - unregisters the SoundWire Slave driver 218 * @drv: driver to unregister 219 */ 220 void sdw_unregister_driver(struct sdw_driver *drv) 221 { 222 driver_unregister(&drv->driver); 223 } 224 EXPORT_SYMBOL_GPL(sdw_unregister_driver); 225 226 static int __init sdw_bus_init(void) 227 { 228 sdw_debugfs_init(); 229 return bus_register(&sdw_bus_type); 230 } 231 232 static void __exit sdw_bus_exit(void) 233 { 234 sdw_debugfs_exit(); 235 bus_unregister(&sdw_bus_type); 236 } 237 238 postcore_initcall(sdw_bus_init); 239 module_exit(sdw_bus_exit); 240 241 MODULE_DESCRIPTION("SoundWire bus"); 242 MODULE_LICENSE("GPL v2"); 243