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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (c) 2012-2015, The Linux Foundation. All rights reserved.4 */5#include <linux/kernel.h>6#include <linux/errno.h>7#include <linux/idr.h>8#include <linux/slab.h>9#include <linux/module.h>10#include <linux/of.h>11#include <linux/of_device.h>12#include <linux/platform_device.h>13#include <linux/spmi.h>14#include <linux/pm_runtime.h>15 16#include <dt-bindings/spmi/spmi.h>17#define CREATE_TRACE_POINTS18#include <trace/events/spmi.h>19 20static bool is_registered;21static DEFINE_IDA(ctrl_ida);22 23static void spmi_dev_release(struct device *dev)24{25	struct spmi_device *sdev = to_spmi_device(dev);26 27	kfree(sdev);28}29 30static const struct device_type spmi_dev_type = {31	.release	= spmi_dev_release,32};33 34static void spmi_ctrl_release(struct device *dev)35{36	struct spmi_controller *ctrl = to_spmi_controller(dev);37 38	ida_free(&ctrl_ida, ctrl->nr);39	kfree(ctrl);40}41 42static const struct device_type spmi_ctrl_type = {43	.release	= spmi_ctrl_release,44};45 46static int spmi_device_match(struct device *dev, const struct device_driver *drv)47{48	if (of_driver_match_device(dev, drv))49		return 1;50 51	if (drv->name)52		return strncmp(dev_name(dev), drv->name,53			       SPMI_NAME_SIZE) == 0;54 55	return 0;56}57 58/**59 * spmi_device_add() - add a device previously constructed via spmi_device_alloc()60 * @sdev:	spmi_device to be added61 */62int spmi_device_add(struct spmi_device *sdev)63{64	struct spmi_controller *ctrl = sdev->ctrl;65	int err;66 67	dev_set_name(&sdev->dev, "%d-%02x", ctrl->nr, sdev->usid);68 69	err = device_add(&sdev->dev);70	if (err < 0) {71		dev_err(&sdev->dev, "Can't add %s, status %d\n",72			dev_name(&sdev->dev), err);73		goto err_device_add;74	}75 76	dev_dbg(&sdev->dev, "device %s registered\n", dev_name(&sdev->dev));77 78err_device_add:79	return err;80}81EXPORT_SYMBOL_GPL(spmi_device_add);82 83/**84 * spmi_device_remove(): remove an SPMI device85 * @sdev:	spmi_device to be removed86 */87void spmi_device_remove(struct spmi_device *sdev)88{89	device_unregister(&sdev->dev);90}91EXPORT_SYMBOL_GPL(spmi_device_remove);92 93static inline int94spmi_cmd(struct spmi_controller *ctrl, u8 opcode, u8 sid)95{96	int ret;97 98	if (!ctrl || !ctrl->cmd || ctrl->dev.type != &spmi_ctrl_type)99		return -EINVAL;100 101	ret = ctrl->cmd(ctrl, opcode, sid);102	trace_spmi_cmd(opcode, sid, ret);103	return ret;104}105 106static inline int spmi_read_cmd(struct spmi_controller *ctrl, u8 opcode,107				u8 sid, u16 addr, u8 *buf, size_t len)108{109	int ret;110 111	if (!ctrl || !ctrl->read_cmd || ctrl->dev.type != &spmi_ctrl_type)112		return -EINVAL;113 114	trace_spmi_read_begin(opcode, sid, addr);115	ret = ctrl->read_cmd(ctrl, opcode, sid, addr, buf, len);116	trace_spmi_read_end(opcode, sid, addr, ret, len, buf);117	return ret;118}119 120static inline int spmi_write_cmd(struct spmi_controller *ctrl, u8 opcode,121				 u8 sid, u16 addr, const u8 *buf, size_t len)122{123	int ret;124 125	if (!ctrl || !ctrl->write_cmd || ctrl->dev.type != &spmi_ctrl_type)126		return -EINVAL;127 128	trace_spmi_write_begin(opcode, sid, addr, len, buf);129	ret = ctrl->write_cmd(ctrl, opcode, sid, addr, buf, len);130	trace_spmi_write_end(opcode, sid, addr, ret);131	return ret;132}133 134/**135 * spmi_register_read() - register read136 * @sdev:	SPMI device.137 * @addr:	slave register address (5-bit address).138 * @buf:	buffer to be populated with data from the Slave.139 *140 * Reads 1 byte of data from a Slave device register.141 */142int spmi_register_read(struct spmi_device *sdev, u8 addr, u8 *buf)143{144	/* 5-bit register address */145	if (addr > 0x1F)146		return -EINVAL;147 148	return spmi_read_cmd(sdev->ctrl, SPMI_CMD_READ, sdev->usid, addr,149			     buf, 1);150}151EXPORT_SYMBOL_GPL(spmi_register_read);152 153/**154 * spmi_ext_register_read() - extended register read155 * @sdev:	SPMI device.156 * @addr:	slave register address (8-bit address).157 * @buf:	buffer to be populated with data from the Slave.158 * @len:	the request number of bytes to read (up to 16 bytes).159 *160 * Reads up to 16 bytes of data from the extended register space on a161 * Slave device.162 */163int spmi_ext_register_read(struct spmi_device *sdev, u8 addr, u8 *buf,164			   size_t len)165{166	/* 8-bit register address, up to 16 bytes */167	if (len == 0 || len > 16)168		return -EINVAL;169 170	return spmi_read_cmd(sdev->ctrl, SPMI_CMD_EXT_READ, sdev->usid, addr,171			     buf, len);172}173EXPORT_SYMBOL_GPL(spmi_ext_register_read);174 175/**176 * spmi_ext_register_readl() - extended register read long177 * @sdev:	SPMI device.178 * @addr:	slave register address (16-bit address).179 * @buf:	buffer to be populated with data from the Slave.180 * @len:	the request number of bytes to read (up to 8 bytes).181 *182 * Reads up to 8 bytes of data from the extended register space on a183 * Slave device using 16-bit address.184 */185int spmi_ext_register_readl(struct spmi_device *sdev, u16 addr, u8 *buf,186			    size_t len)187{188	/* 16-bit register address, up to 8 bytes */189	if (len == 0 || len > 8)190		return -EINVAL;191 192	return spmi_read_cmd(sdev->ctrl, SPMI_CMD_EXT_READL, sdev->usid, addr,193			     buf, len);194}195EXPORT_SYMBOL_GPL(spmi_ext_register_readl);196 197/**198 * spmi_register_write() - register write199 * @sdev:	SPMI device200 * @addr:	slave register address (5-bit address).201 * @data:	buffer containing the data to be transferred to the Slave.202 *203 * Writes 1 byte of data to a Slave device register.204 */205int spmi_register_write(struct spmi_device *sdev, u8 addr, u8 data)206{207	/* 5-bit register address */208	if (addr > 0x1F)209		return -EINVAL;210 211	return spmi_write_cmd(sdev->ctrl, SPMI_CMD_WRITE, sdev->usid, addr,212			      &data, 1);213}214EXPORT_SYMBOL_GPL(spmi_register_write);215 216/**217 * spmi_register_zero_write() - register zero write218 * @sdev:	SPMI device.219 * @data:	the data to be written to register 0 (7-bits).220 *221 * Writes data to register 0 of the Slave device.222 */223int spmi_register_zero_write(struct spmi_device *sdev, u8 data)224{225	return spmi_write_cmd(sdev->ctrl, SPMI_CMD_ZERO_WRITE, sdev->usid, 0,226			      &data, 1);227}228EXPORT_SYMBOL_GPL(spmi_register_zero_write);229 230/**231 * spmi_ext_register_write() - extended register write232 * @sdev:	SPMI device.233 * @addr:	slave register address (8-bit address).234 * @buf:	buffer containing the data to be transferred to the Slave.235 * @len:	the request number of bytes to read (up to 16 bytes).236 *237 * Writes up to 16 bytes of data to the extended register space of a238 * Slave device.239 */240int spmi_ext_register_write(struct spmi_device *sdev, u8 addr, const u8 *buf,241			    size_t len)242{243	/* 8-bit register address, up to 16 bytes */244	if (len == 0 || len > 16)245		return -EINVAL;246 247	return spmi_write_cmd(sdev->ctrl, SPMI_CMD_EXT_WRITE, sdev->usid, addr,248			      buf, len);249}250EXPORT_SYMBOL_GPL(spmi_ext_register_write);251 252/**253 * spmi_ext_register_writel() - extended register write long254 * @sdev:	SPMI device.255 * @addr:	slave register address (16-bit address).256 * @buf:	buffer containing the data to be transferred to the Slave.257 * @len:	the request number of bytes to read (up to 8 bytes).258 *259 * Writes up to 8 bytes of data to the extended register space of a260 * Slave device using 16-bit address.261 */262int spmi_ext_register_writel(struct spmi_device *sdev, u16 addr, const u8 *buf,263			     size_t len)264{265	/* 4-bit Slave Identifier, 16-bit register address, up to 8 bytes */266	if (len == 0 || len > 8)267		return -EINVAL;268 269	return spmi_write_cmd(sdev->ctrl, SPMI_CMD_EXT_WRITEL, sdev->usid,270			      addr, buf, len);271}272EXPORT_SYMBOL_GPL(spmi_ext_register_writel);273 274/**275 * spmi_command_reset() - sends RESET command to the specified slave276 * @sdev:	SPMI device.277 *278 * The Reset command initializes the Slave and forces all registers to279 * their reset values. The Slave shall enter the STARTUP state after280 * receiving a Reset command.281 */282int spmi_command_reset(struct spmi_device *sdev)283{284	return spmi_cmd(sdev->ctrl, SPMI_CMD_RESET, sdev->usid);285}286EXPORT_SYMBOL_GPL(spmi_command_reset);287 288/**289 * spmi_command_sleep() - sends SLEEP command to the specified SPMI device290 * @sdev:	SPMI device.291 *292 * The Sleep command causes the Slave to enter the user defined SLEEP state.293 */294int spmi_command_sleep(struct spmi_device *sdev)295{296	return spmi_cmd(sdev->ctrl, SPMI_CMD_SLEEP, sdev->usid);297}298EXPORT_SYMBOL_GPL(spmi_command_sleep);299 300/**301 * spmi_command_wakeup() - sends WAKEUP command to the specified SPMI device302 * @sdev:	SPMI device.303 *304 * The Wakeup command causes the Slave to move from the SLEEP state to305 * the ACTIVE state.306 */307int spmi_command_wakeup(struct spmi_device *sdev)308{309	return spmi_cmd(sdev->ctrl, SPMI_CMD_WAKEUP, sdev->usid);310}311EXPORT_SYMBOL_GPL(spmi_command_wakeup);312 313/**314 * spmi_command_shutdown() - sends SHUTDOWN command to the specified SPMI device315 * @sdev:	SPMI device.316 *317 * The Shutdown command causes the Slave to enter the SHUTDOWN state.318 */319int spmi_command_shutdown(struct spmi_device *sdev)320{321	return spmi_cmd(sdev->ctrl, SPMI_CMD_SHUTDOWN, sdev->usid);322}323EXPORT_SYMBOL_GPL(spmi_command_shutdown);324 325static int spmi_drv_probe(struct device *dev)326{327	const struct spmi_driver *sdrv = to_spmi_driver(dev->driver);328	struct spmi_device *sdev = to_spmi_device(dev);329	int err;330 331	pm_runtime_get_noresume(dev);332	pm_runtime_set_active(dev);333	pm_runtime_enable(dev);334 335	err = sdrv->probe(sdev);336	if (err)337		goto fail_probe;338 339	return 0;340 341fail_probe:342	pm_runtime_disable(dev);343	pm_runtime_set_suspended(dev);344	pm_runtime_put_noidle(dev);345	return err;346}347 348static void spmi_drv_remove(struct device *dev)349{350	const struct spmi_driver *sdrv = to_spmi_driver(dev->driver);351 352	pm_runtime_get_sync(dev);353	if (sdrv->remove)354		sdrv->remove(to_spmi_device(dev));355	pm_runtime_put_noidle(dev);356 357	pm_runtime_disable(dev);358	pm_runtime_set_suspended(dev);359	pm_runtime_put_noidle(dev);360}361 362static void spmi_drv_shutdown(struct device *dev)363{364	const struct spmi_driver *sdrv = to_spmi_driver(dev->driver);365 366	if (sdrv && sdrv->shutdown)367		sdrv->shutdown(to_spmi_device(dev));368}369 370static int spmi_drv_uevent(const struct device *dev, struct kobj_uevent_env *env)371{372	int ret;373 374	ret = of_device_uevent_modalias(dev, env);375	if (ret != -ENODEV)376		return ret;377 378	return 0;379}380 381static const struct bus_type spmi_bus_type = {382	.name		= "spmi",383	.match		= spmi_device_match,384	.probe		= spmi_drv_probe,385	.remove		= spmi_drv_remove,386	.shutdown	= spmi_drv_shutdown,387	.uevent		= spmi_drv_uevent,388};389 390/**391 * spmi_find_device_by_of_node() - look up an SPMI device from a device node392 *393 * @np:		device node394 *395 * Takes a reference to the embedded struct device which needs to be dropped396 * after use.397 *398 * Returns the struct spmi_device associated with a device node or NULL.399 */400struct spmi_device *spmi_find_device_by_of_node(struct device_node *np)401{402	struct device *dev = bus_find_device_by_of_node(&spmi_bus_type, np);403 404	if (dev)405		return to_spmi_device(dev);406	return NULL;407}408EXPORT_SYMBOL_GPL(spmi_find_device_by_of_node);409 410/**411 * spmi_device_alloc() - Allocate a new SPMI device412 * @ctrl:	associated controller413 *414 * Caller is responsible for either calling spmi_device_add() to add the415 * newly allocated controller, or calling spmi_device_put() to discard it.416 */417struct spmi_device *spmi_device_alloc(struct spmi_controller *ctrl)418{419	struct spmi_device *sdev;420 421	sdev = kzalloc(sizeof(*sdev), GFP_KERNEL);422	if (!sdev)423		return NULL;424 425	sdev->ctrl = ctrl;426	device_initialize(&sdev->dev);427	sdev->dev.parent = &ctrl->dev;428	sdev->dev.bus = &spmi_bus_type;429	sdev->dev.type = &spmi_dev_type;430	return sdev;431}432EXPORT_SYMBOL_GPL(spmi_device_alloc);433 434/**435 * spmi_controller_alloc() - Allocate a new SPMI controller436 * @parent:	parent device437 * @size:	size of private data438 *439 * Caller is responsible for either calling spmi_controller_add() to add the440 * newly allocated controller, or calling spmi_controller_put() to discard it.441 * The allocated private data region may be accessed via442 * spmi_controller_get_drvdata()443 */444struct spmi_controller *spmi_controller_alloc(struct device *parent,445					      size_t size)446{447	struct spmi_controller *ctrl;448	int id;449 450	if (WARN_ON(!parent))451		return ERR_PTR(-EINVAL);452 453	ctrl = kzalloc(sizeof(*ctrl) + size, GFP_KERNEL);454	if (!ctrl)455		return ERR_PTR(-ENOMEM);456 457	device_initialize(&ctrl->dev);458	ctrl->dev.type = &spmi_ctrl_type;459	ctrl->dev.bus = &spmi_bus_type;460	ctrl->dev.parent = parent;461	ctrl->dev.of_node = parent->of_node;462	spmi_controller_set_drvdata(ctrl, &ctrl[1]);463 464	id = ida_alloc(&ctrl_ida, GFP_KERNEL);465	if (id < 0) {466		dev_err(parent,467			"unable to allocate SPMI controller identifier.\n");468		spmi_controller_put(ctrl);469		return ERR_PTR(id);470	}471 472	ctrl->nr = id;473	dev_set_name(&ctrl->dev, "spmi-%d", id);474 475	dev_dbg(&ctrl->dev, "allocated controller 0x%p id %d\n", ctrl, id);476	return ctrl;477}478EXPORT_SYMBOL_GPL(spmi_controller_alloc);479 480static void of_spmi_register_devices(struct spmi_controller *ctrl)481{482	struct device_node *node;483	int err;484 485	if (!ctrl->dev.of_node)486		return;487 488	for_each_available_child_of_node(ctrl->dev.of_node, node) {489		struct spmi_device *sdev;490		u32 reg[2];491 492		dev_dbg(&ctrl->dev, "adding child %pOF\n", node);493 494		err = of_property_read_u32_array(node, "reg", reg, 2);495		if (err) {496			dev_err(&ctrl->dev,497				"node %pOF err (%d) does not have 'reg' property\n",498				node, err);499			continue;500		}501 502		if (reg[1] != SPMI_USID) {503			dev_err(&ctrl->dev,504				"node %pOF contains unsupported 'reg' entry\n",505				node);506			continue;507		}508 509		if (reg[0] >= SPMI_MAX_SLAVE_ID) {510			dev_err(&ctrl->dev, "invalid usid on node %pOF\n", node);511			continue;512		}513 514		dev_dbg(&ctrl->dev, "read usid %02x\n", reg[0]);515 516		sdev = spmi_device_alloc(ctrl);517		if (!sdev)518			continue;519 520		sdev->dev.of_node = node;521		sdev->usid = (u8)reg[0];522 523		err = spmi_device_add(sdev);524		if (err) {525			dev_err(&sdev->dev,526				"failure adding device. status %d\n", err);527			spmi_device_put(sdev);528		}529	}530}531 532/**533 * spmi_controller_add() - Add an SPMI controller534 * @ctrl:	controller to be registered.535 *536 * Register a controller previously allocated via spmi_controller_alloc() with537 * the SPMI core.538 */539int spmi_controller_add(struct spmi_controller *ctrl)540{541	int ret;542 543	/* Can't register until after driver model init */544	if (WARN_ON(!is_registered))545		return -EAGAIN;546 547	ret = device_add(&ctrl->dev);548	if (ret)549		return ret;550 551	if (IS_ENABLED(CONFIG_OF))552		of_spmi_register_devices(ctrl);553 554	dev_dbg(&ctrl->dev, "spmi-%d registered: dev:%p\n",555		ctrl->nr, &ctrl->dev);556 557	return 0;558};559EXPORT_SYMBOL_GPL(spmi_controller_add);560 561/* Remove a device associated with a controller */562static int spmi_ctrl_remove_device(struct device *dev, void *data)563{564	struct spmi_device *spmidev = to_spmi_device(dev);565 566	if (dev->type == &spmi_dev_type)567		spmi_device_remove(spmidev);568	return 0;569}570 571/**572 * spmi_controller_remove(): remove an SPMI controller573 * @ctrl:	controller to remove574 *575 * Remove a SPMI controller.  Caller is responsible for calling576 * spmi_controller_put() to discard the allocated controller.577 */578void spmi_controller_remove(struct spmi_controller *ctrl)579{580	if (!ctrl)581		return;582 583	device_for_each_child(&ctrl->dev, NULL, spmi_ctrl_remove_device);584	device_del(&ctrl->dev);585}586EXPORT_SYMBOL_GPL(spmi_controller_remove);587 588/**589 * __spmi_driver_register() - Register client driver with SPMI core590 * @sdrv:	client driver to be associated with client-device.591 * @owner:	module owner592 *593 * This API will register the client driver with the SPMI framework.594 * It is typically called from the driver's module-init function.595 */596int __spmi_driver_register(struct spmi_driver *sdrv, struct module *owner)597{598	sdrv->driver.bus = &spmi_bus_type;599	sdrv->driver.owner = owner;600	return driver_register(&sdrv->driver);601}602EXPORT_SYMBOL_GPL(__spmi_driver_register);603 604static void __exit spmi_exit(void)605{606	bus_unregister(&spmi_bus_type);607}608module_exit(spmi_exit);609 610static int __init spmi_init(void)611{612	int ret;613 614	ret = bus_register(&spmi_bus_type);615	if (ret)616		return ret;617 618	is_registered = true;619	return 0;620}621postcore_initcall(spmi_init);622 623MODULE_LICENSE("GPL v2");624MODULE_DESCRIPTION("SPMI module");625MODULE_ALIAS("platform:spmi");626