2 * Copyright (C) 2016-2017 Linaro Ltd., Rob Herring <robh@kernel.org>
4 * Based on drivers/spmi/spmi.c:
5 * Copyright (c) 2012-2015, The Linux Foundation. All rights reserved.
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 and
9 * only version 2 as published by the Free Software Foundation.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
17 #include <linux/errno.h>
18 #include <linux/idr.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
22 #include <linux/of_device.h>
23 #include <linux/serdev.h>
24 #include <linux/slab.h>
26 static bool is_registered;
27 static DEFINE_IDA(ctrl_ida);
29 static void serdev_device_release(struct device *dev)
31 struct serdev_device *serdev = to_serdev_device(dev);
35 static const struct device_type serdev_device_type = {
36 .release = serdev_device_release,
39 static void serdev_ctrl_release(struct device *dev)
41 struct serdev_controller *ctrl = to_serdev_controller(dev);
42 ida_simple_remove(&ctrl_ida, ctrl->nr);
46 static const struct device_type serdev_ctrl_type = {
47 .release = serdev_ctrl_release,
50 static int serdev_device_match(struct device *dev, struct device_driver *drv)
52 /* TODO: ACPI and platform matching */
53 return of_driver_match_device(dev, drv);
56 static int serdev_uevent(struct device *dev, struct kobj_uevent_env *env)
58 /* TODO: ACPI and platform modalias */
59 return of_device_uevent_modalias(dev, env);
63 * serdev_device_add() - add a device previously constructed via serdev_device_alloc()
64 * @serdev: serdev_device to be added
66 int serdev_device_add(struct serdev_device *serdev)
68 struct serdev_controller *ctrl = serdev->ctrl;
69 struct device *parent = serdev->dev.parent;
72 dev_set_name(&serdev->dev, "%s-%d", dev_name(parent), serdev->nr);
74 /* Only a single slave device is currently supported. */
76 dev_err(&serdev->dev, "controller busy\n");
79 ctrl->serdev = serdev;
81 err = device_add(&serdev->dev);
83 dev_err(&serdev->dev, "Can't add %s, status %d\n",
84 dev_name(&serdev->dev), err);
85 goto err_clear_serdev;
88 dev_dbg(&serdev->dev, "device %s registered\n", dev_name(&serdev->dev));
96 EXPORT_SYMBOL_GPL(serdev_device_add);
99 * serdev_device_remove(): remove an serdev device
100 * @serdev: serdev_device to be removed
102 void serdev_device_remove(struct serdev_device *serdev)
104 struct serdev_controller *ctrl = serdev->ctrl;
106 device_unregister(&serdev->dev);
109 EXPORT_SYMBOL_GPL(serdev_device_remove);
111 int serdev_device_open(struct serdev_device *serdev)
113 struct serdev_controller *ctrl = serdev->ctrl;
115 if (!ctrl || !ctrl->ops->open)
118 return ctrl->ops->open(ctrl);
120 EXPORT_SYMBOL_GPL(serdev_device_open);
122 void serdev_device_close(struct serdev_device *serdev)
124 struct serdev_controller *ctrl = serdev->ctrl;
126 if (!ctrl || !ctrl->ops->close)
129 ctrl->ops->close(ctrl);
131 EXPORT_SYMBOL_GPL(serdev_device_close);
133 void serdev_device_write_wakeup(struct serdev_device *serdev)
135 complete(&serdev->write_comp);
137 EXPORT_SYMBOL_GPL(serdev_device_write_wakeup);
139 int serdev_device_write_buf(struct serdev_device *serdev,
140 const unsigned char *buf, size_t count)
142 struct serdev_controller *ctrl = serdev->ctrl;
144 if (!ctrl || !ctrl->ops->write_buf)
147 return ctrl->ops->write_buf(ctrl, buf, count);
149 EXPORT_SYMBOL_GPL(serdev_device_write_buf);
151 int serdev_device_write(struct serdev_device *serdev,
152 const unsigned char *buf, size_t count,
153 unsigned long timeout)
155 struct serdev_controller *ctrl = serdev->ctrl;
158 if (!ctrl || !ctrl->ops->write_buf ||
159 (timeout && !serdev->ops->write_wakeup))
162 mutex_lock(&serdev->write_lock);
164 reinit_completion(&serdev->write_comp);
166 ret = ctrl->ops->write_buf(ctrl, buf, count);
174 (timeout = wait_for_completion_timeout(&serdev->write_comp,
176 mutex_unlock(&serdev->write_lock);
177 return ret < 0 ? ret : (count ? -ETIMEDOUT : 0);
179 EXPORT_SYMBOL_GPL(serdev_device_write);
181 void serdev_device_write_flush(struct serdev_device *serdev)
183 struct serdev_controller *ctrl = serdev->ctrl;
185 if (!ctrl || !ctrl->ops->write_flush)
188 ctrl->ops->write_flush(ctrl);
190 EXPORT_SYMBOL_GPL(serdev_device_write_flush);
192 int serdev_device_write_room(struct serdev_device *serdev)
194 struct serdev_controller *ctrl = serdev->ctrl;
196 if (!ctrl || !ctrl->ops->write_room)
199 return serdev->ctrl->ops->write_room(ctrl);
201 EXPORT_SYMBOL_GPL(serdev_device_write_room);
203 unsigned int serdev_device_set_baudrate(struct serdev_device *serdev, unsigned int speed)
205 struct serdev_controller *ctrl = serdev->ctrl;
207 if (!ctrl || !ctrl->ops->set_baudrate)
210 return ctrl->ops->set_baudrate(ctrl, speed);
213 EXPORT_SYMBOL_GPL(serdev_device_set_baudrate);
215 void serdev_device_set_flow_control(struct serdev_device *serdev, bool enable)
217 struct serdev_controller *ctrl = serdev->ctrl;
219 if (!ctrl || !ctrl->ops->set_flow_control)
222 ctrl->ops->set_flow_control(ctrl, enable);
224 EXPORT_SYMBOL_GPL(serdev_device_set_flow_control);
226 void serdev_device_wait_until_sent(struct serdev_device *serdev, long timeout)
228 struct serdev_controller *ctrl = serdev->ctrl;
230 if (!ctrl || !ctrl->ops->wait_until_sent)
233 ctrl->ops->wait_until_sent(ctrl, timeout);
235 EXPORT_SYMBOL_GPL(serdev_device_wait_until_sent);
237 int serdev_device_get_tiocm(struct serdev_device *serdev)
239 struct serdev_controller *ctrl = serdev->ctrl;
241 if (!ctrl || !ctrl->ops->get_tiocm)
244 return ctrl->ops->get_tiocm(ctrl);
246 EXPORT_SYMBOL_GPL(serdev_device_get_tiocm);
248 int serdev_device_set_tiocm(struct serdev_device *serdev, int set, int clear)
250 struct serdev_controller *ctrl = serdev->ctrl;
252 if (!ctrl || !ctrl->ops->set_tiocm)
255 return ctrl->ops->set_tiocm(ctrl, set, clear);
257 EXPORT_SYMBOL_GPL(serdev_device_set_tiocm);
259 static int serdev_drv_probe(struct device *dev)
261 const struct serdev_device_driver *sdrv = to_serdev_device_driver(dev->driver);
263 return sdrv->probe(to_serdev_device(dev));
266 static int serdev_drv_remove(struct device *dev)
268 const struct serdev_device_driver *sdrv = to_serdev_device_driver(dev->driver);
270 sdrv->remove(to_serdev_device(dev));
274 static ssize_t modalias_show(struct device *dev,
275 struct device_attribute *attr, char *buf)
277 return of_device_modalias(dev, buf, PAGE_SIZE);
279 DEVICE_ATTR_RO(modalias);
281 static struct attribute *serdev_device_attrs[] = {
282 &dev_attr_modalias.attr,
285 ATTRIBUTE_GROUPS(serdev_device);
287 static struct bus_type serdev_bus_type = {
289 .match = serdev_device_match,
290 .probe = serdev_drv_probe,
291 .remove = serdev_drv_remove,
292 .uevent = serdev_uevent,
293 .dev_groups = serdev_device_groups,
297 * serdev_controller_alloc() - Allocate a new serdev device
298 * @ctrl: associated controller
300 * Caller is responsible for either calling serdev_device_add() to add the
301 * newly allocated controller, or calling serdev_device_put() to discard it.
303 struct serdev_device *serdev_device_alloc(struct serdev_controller *ctrl)
305 struct serdev_device *serdev;
307 serdev = kzalloc(sizeof(*serdev), GFP_KERNEL);
312 device_initialize(&serdev->dev);
313 serdev->dev.parent = &ctrl->dev;
314 serdev->dev.bus = &serdev_bus_type;
315 serdev->dev.type = &serdev_device_type;
316 init_completion(&serdev->write_comp);
317 mutex_init(&serdev->write_lock);
320 EXPORT_SYMBOL_GPL(serdev_device_alloc);
323 * serdev_controller_alloc() - Allocate a new serdev controller
324 * @parent: parent device
325 * @size: size of private data
327 * Caller is responsible for either calling serdev_controller_add() to add the
328 * newly allocated controller, or calling serdev_controller_put() to discard it.
329 * The allocated private data region may be accessed via
330 * serdev_controller_get_drvdata()
332 struct serdev_controller *serdev_controller_alloc(struct device *parent,
335 struct serdev_controller *ctrl;
338 if (WARN_ON(!parent))
341 ctrl = kzalloc(sizeof(*ctrl) + size, GFP_KERNEL);
345 device_initialize(&ctrl->dev);
346 ctrl->dev.type = &serdev_ctrl_type;
347 ctrl->dev.bus = &serdev_bus_type;
348 ctrl->dev.parent = parent;
349 ctrl->dev.of_node = parent->of_node;
350 serdev_controller_set_drvdata(ctrl, &ctrl[1]);
352 id = ida_simple_get(&ctrl_ida, 0, 0, GFP_KERNEL);
355 "unable to allocate serdev controller identifier.\n");
356 serdev_controller_put(ctrl);
361 dev_set_name(&ctrl->dev, "serial%d", id);
363 dev_dbg(&ctrl->dev, "allocated controller 0x%p id %d\n", ctrl, id);
366 EXPORT_SYMBOL_GPL(serdev_controller_alloc);
368 static int of_serdev_register_devices(struct serdev_controller *ctrl)
370 struct device_node *node;
371 struct serdev_device *serdev = NULL;
375 for_each_available_child_of_node(ctrl->dev.of_node, node) {
376 if (!of_get_property(node, "compatible", NULL))
379 dev_dbg(&ctrl->dev, "adding child %pOF\n", node);
381 serdev = serdev_device_alloc(ctrl);
385 serdev->dev.of_node = node;
387 err = serdev_device_add(serdev);
389 dev_err(&serdev->dev,
390 "failure adding device. status %d\n", err);
391 serdev_device_put(serdev);
402 * serdev_controller_add() - Add an serdev controller
403 * @ctrl: controller to be registered.
405 * Register a controller previously allocated via serdev_controller_alloc() with
408 int serdev_controller_add(struct serdev_controller *ctrl)
412 /* Can't register until after driver model init */
413 if (WARN_ON(!is_registered))
416 ret = device_add(&ctrl->dev);
420 ret = of_serdev_register_devices(ctrl);
424 dev_dbg(&ctrl->dev, "serdev%d registered: dev:%p\n",
425 ctrl->nr, &ctrl->dev);
429 device_del(&ctrl->dev);
432 EXPORT_SYMBOL_GPL(serdev_controller_add);
434 /* Remove a device associated with a controller */
435 static int serdev_remove_device(struct device *dev, void *data)
437 struct serdev_device *serdev = to_serdev_device(dev);
438 if (dev->type == &serdev_device_type)
439 serdev_device_remove(serdev);
444 * serdev_controller_remove(): remove an serdev controller
445 * @ctrl: controller to remove
447 * Remove a serdev controller. Caller is responsible for calling
448 * serdev_controller_put() to discard the allocated controller.
450 void serdev_controller_remove(struct serdev_controller *ctrl)
457 dummy = device_for_each_child(&ctrl->dev, NULL,
458 serdev_remove_device);
459 device_del(&ctrl->dev);
461 EXPORT_SYMBOL_GPL(serdev_controller_remove);
464 * serdev_driver_register() - Register client driver with serdev core
465 * @sdrv: client driver to be associated with client-device.
467 * This API will register the client driver with the serdev framework.
468 * It is typically called from the driver's module-init function.
470 int __serdev_device_driver_register(struct serdev_device_driver *sdrv, struct module *owner)
472 sdrv->driver.bus = &serdev_bus_type;
473 sdrv->driver.owner = owner;
475 /* force drivers to async probe so I/O is possible in probe */
476 sdrv->driver.probe_type = PROBE_PREFER_ASYNCHRONOUS;
478 return driver_register(&sdrv->driver);
480 EXPORT_SYMBOL_GPL(__serdev_device_driver_register);
482 static void __exit serdev_exit(void)
484 bus_unregister(&serdev_bus_type);
485 ida_destroy(&ctrl_ida);
487 module_exit(serdev_exit);
489 static int __init serdev_init(void)
493 ret = bus_register(&serdev_bus_type);
497 is_registered = true;
500 /* Must be before serial drivers register */
501 postcore_initcall(serdev_init);
503 MODULE_AUTHOR("Rob Herring <robh@kernel.org>");
504 MODULE_LICENSE("GPL v2");
505 MODULE_DESCRIPTION("Serial attached device bus");