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1// SPDX-License-Identifier: GPL-2.02// 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 id15 * @slave: SoundWire Slave Device16 * @drv: SoundWire Slave Driver17 *18 * The match is done by comparing the mfg_id and part_id from the19 * struct sdw_device_id.20 */21static const struct sdw_device_id *22sdw_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 38static 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 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, "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, modalias, sizeof(modalias));68 69	if (add_uevent_var(env, "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	int ret;87 88	/*89	 * fw description is mandatory to bind90	 */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 of130	 * 300ms131	 *132	 * TODO: check the timeouts and driver removal case133	 */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 driver144	 * 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 160static 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	if (slave->prop.use_domain_irq)171		sdw_irq_dispose_mapping(slave);172 173	mutex_unlock(&slave->sdw_dev_lock);174 175	if (drv->remove)176		ret = drv->remove(slave);177 178	dev_pm_domain_detach(dev, false);179 180	return ret;181}182 183static void sdw_drv_shutdown(struct device *dev)184{185	struct sdw_slave *slave = dev_to_sdw_dev(dev);186	struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);187 188	if (drv->shutdown)189		drv->shutdown(slave);190}191 192/**193 * __sdw_register_driver() - register a SoundWire Slave driver194 * @drv: driver to register195 * @owner: owning module/driver196 *197 * Return: zero on success, else a negative error code.198 */199int __sdw_register_driver(struct sdw_driver *drv, struct module *owner)200{201	drv->driver.bus = &sdw_bus_type;202 203	if (!drv->probe) {204		pr_err("driver %s didn't provide SDW probe routine\n",205				drv->driver.name);206		return -EINVAL;207	}208 209	drv->driver.owner = owner;210	drv->driver.probe = sdw_drv_probe;211	drv->driver.remove = sdw_drv_remove;212	drv->driver.shutdown = sdw_drv_shutdown;213	drv->driver.dev_groups = sdw_attr_groups;214 215	return driver_register(&drv->driver);216}217EXPORT_SYMBOL_GPL(__sdw_register_driver);218 219/**220 * sdw_unregister_driver() - unregisters the SoundWire Slave driver221 * @drv: driver to unregister222 */223void sdw_unregister_driver(struct sdw_driver *drv)224{225	driver_unregister(&drv->driver);226}227EXPORT_SYMBOL_GPL(sdw_unregister_driver);228 229static int __init sdw_bus_init(void)230{231	sdw_debugfs_init();232	return bus_register(&sdw_bus_type);233}234 235static void __exit sdw_bus_exit(void)236{237	sdw_debugfs_exit();238	bus_unregister(&sdw_bus_type);239}240 241postcore_initcall(sdw_bus_init);242module_exit(sdw_bus_exit);243 244MODULE_DESCRIPTION("SoundWire bus");245MODULE_LICENSE("GPL v2");246