soundwire: Add SoundWire bus type (9251345d) · Commits · e / devices / android_kernel_fairphone_FP5

drivers/Kconfig

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		@@ -153,6 +153,8 @@ source "drivers/remoteproc/Kconfig"

		source "drivers/rpmsg/Kconfig"

		source "drivers/soundwire/Kconfig"

		source "drivers/soc/Kconfig"

		source "drivers/devfreq/Kconfig"

drivers/Makefile

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		@@ -158,6 +158,7 @@ obj-$(CONFIG_MAILBOX) += mailbox/
		obj-$(CONFIG_HWSPINLOCK) += hwspinlock/
		obj-$(CONFIG_REMOTEPROC) += remoteproc/
		obj-$(CONFIG_RPMSG) += rpmsg/
		obj-$(CONFIG_SOUNDWIRE) += soundwire/

		# Virtualization drivers
		obj-$(CONFIG_VIRT_DRIVERS) += virt/

drivers/soundwire/Kconfig

0 → 100644

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		#
		# SoundWire subsystem configuration
		#

		menuconfig SOUNDWIRE
		bool "SoundWire support"
		---help---
		SoundWire is a 2-Pin interface with data and clock line ratified
		by the MIPI Alliance. SoundWire is used for transporting data
		typically related to audio functions. SoundWire interface is
		optimized to integrate audio devices in mobile or mobile inspired
		systems. Say Y to enable this subsystem, N if you do not have such
		a device

		if SOUNDWIRE

		comment "SoundWire Devices"

		config SOUNDWIRE_BUS
		tristate

		endif

drivers/soundwire/Makefile

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		#
		# Makefile for soundwire core
		#

		#Bus Objs
		soundwire-bus-objs := bus_type.o
		obj-$(CONFIG_SOUNDWIRE_BUS) += soundwire-bus.o

drivers/soundwire/bus_type.c

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		// SPDX-License-Identifier: GPL-2.0
		// Copyright(c) 2015-17 Intel Corporation.

		#include <linux/module.h>
		#include <linux/mod_devicetable.h>
		#include <linux/pm_domain.h>
		#include <linux/soundwire/sdw.h>
		#include <linux/soundwire/sdw_type.h>

		/**
		* sdw_get_device_id - find the matching SoundWire device id
		* @slave: SoundWire Slave Device
		* @drv: SoundWire Slave Driver
		*
		* The match is done by comparing the mfg_id and part_id from the
		* struct sdw_device_id.
		*/
		static const struct sdw_device_id *
		sdw_get_device_id(struct sdw_slave slave, struct sdw_driver drv)
		{
		const struct sdw_device_id *id = drv->id_table;

		while (id && id->mfg_id) {
		if (slave->id.mfg_id == id->mfg_id &&
		slave->id.part_id == id->part_id)
		return id;
		id++;
		}

		return NULL;
		}

		static int sdw_bus_match(struct device dev, struct device_driver ddrv)
		{
		struct sdw_slave *slave = dev_to_sdw_dev(dev);
		struct sdw_driver *drv = drv_to_sdw_driver(ddrv);

		return !!sdw_get_device_id(slave, drv);
		}

		int sdw_slave_modalias(const struct sdw_slave slave, char buf, size_t size)
		{
		/* modalias is sdw:m<mfg_id>p<part_id> */

		return snprintf(buf, size, "sdw:m%04Xp%04X\n",
		slave->id.mfg_id, slave->id.part_id);
		}

		static int sdw_uevent(struct device dev, struct kobj_uevent_env env)
		{
		struct sdw_slave *slave = dev_to_sdw_dev(dev);
		char modalias[32];

		sdw_slave_modalias(slave, modalias, sizeof(modalias));

		if (add_uevent_var(env, "MODALIAS=%s", modalias))
		return -ENOMEM;

		return 0;
		}

		struct bus_type sdw_bus_type = {
		.name = "soundwire",
		.match = sdw_bus_match,
		.uevent = sdw_uevent,
		};
		EXPORT_SYMBOL_GPL(sdw_bus_type);

		static int sdw_drv_probe(struct device *dev)
		{
		struct sdw_slave *slave = dev_to_sdw_dev(dev);
		struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
		const struct sdw_device_id *id;
		int ret;

		id = sdw_get_device_id(slave, drv);
		if (!id)
		return -ENODEV;

		/*
		* attach to power domain but don't turn on (last arg)
		*/
		ret = dev_pm_domain_attach(dev, false);
		if (ret != -EPROBE_DEFER) {
		ret = drv->probe(slave, id);
		if (ret) {
		dev_err(dev, "Probe of %s failed: %d\n", drv->name, ret);
		dev_pm_domain_detach(dev, false);
		}
		}

		return ret;
		}

		static int sdw_drv_remove(struct device *dev)
		{
		struct sdw_slave *slave = dev_to_sdw_dev(dev);
		struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
		int ret = 0;

		if (drv->remove)
		ret = drv->remove(slave);

		dev_pm_domain_detach(dev, false);

		return ret;
		}

		static void sdw_drv_shutdown(struct device *dev)
		{
		struct sdw_slave *slave = dev_to_sdw_dev(dev);
		struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);

		if (drv->shutdown)
		drv->shutdown(slave);
		}

		/**
		* __sdw_register_driver() - register a SoundWire Slave driver
		* @drv: driver to register
		* @owner: owning module/driver
		*
		* Return: zero on success, else a negative error code.
		*/
		int __sdw_register_driver(struct sdw_driver drv, struct module owner)
		{
		drv->driver.bus = &sdw_bus_type;

		if (!drv->probe) {
		pr_err("driver %s didn't provide SDW probe routine\n",
		drv->name);
		return -EINVAL;
		}

		drv->driver.owner = owner;
		drv->driver.probe = sdw_drv_probe;

		if (drv->remove)
		drv->driver.remove = sdw_drv_remove;

		if (drv->shutdown)
		drv->driver.shutdown = sdw_drv_shutdown;

		return driver_register(&drv->driver);
		}
		EXPORT_SYMBOL_GPL(__sdw_register_driver);

		/**
		* sdw_unregister_driver() - unregisters the SoundWire Slave driver
		* @drv: driver to unregister
		*/
		void sdw_unregister_driver(struct sdw_driver *drv)
		{
		driver_unregister(&drv->driver);
		}
		EXPORT_SYMBOL_GPL(sdw_unregister_driver);

		static int __init sdw_bus_init(void)
		{
		return bus_register(&sdw_bus_type);
		}

		static void __exit sdw_bus_exit(void)
		{
		bus_unregister(&sdw_bus_type);
		}

		postcore_initcall(sdw_bus_init);
		module_exit(sdw_bus_exit);

		MODULE_DESCRIPTION("SoundWire bus");
		MODULE_LICENSE("GPL v2");