1 // SPDX-License-Identifier: GPL-2.0
3 * ulpi.c - USB ULPI PHY bus
5 * Copyright (C) 2015 Intel Corporation
7 * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
10 #include <linux/ulpi/interface.h>
11 #include <linux/ulpi/driver.h>
12 #include <linux/ulpi/regs.h>
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/acpi.h>
17 #include <linux/of_device.h>
18 #include <linux/clk/clk-conf.h>
20 /* -------------------------------------------------------------------------- */
22 int ulpi_read(struct ulpi *ulpi, u8 addr)
24 return ulpi->ops->read(ulpi->dev.parent, addr);
26 EXPORT_SYMBOL_GPL(ulpi_read);
28 int ulpi_write(struct ulpi *ulpi, u8 addr, u8 val)
30 return ulpi->ops->write(ulpi->dev.parent, addr, val);
32 EXPORT_SYMBOL_GPL(ulpi_write);
34 /* -------------------------------------------------------------------------- */
36 static int ulpi_match(struct device *dev, struct device_driver *driver)
38 struct ulpi_driver *drv = to_ulpi_driver(driver);
39 struct ulpi *ulpi = to_ulpi_dev(dev);
40 const struct ulpi_device_id *id;
43 * Some ULPI devices don't have a vendor id
44 * or provide an id_table so rely on OF match.
46 if (ulpi->id.vendor == 0 || !drv->id_table)
47 return of_driver_match_device(dev, driver);
49 for (id = drv->id_table; id->vendor; id++)
50 if (id->vendor == ulpi->id.vendor &&
51 id->product == ulpi->id.product)
57 static int ulpi_uevent(struct device *dev, struct kobj_uevent_env *env)
59 struct ulpi *ulpi = to_ulpi_dev(dev);
62 ret = of_device_uevent_modalias(dev, env);
66 if (add_uevent_var(env, "MODALIAS=ulpi:v%04xp%04x",
67 ulpi->id.vendor, ulpi->id.product))
72 static int ulpi_probe(struct device *dev)
74 struct ulpi_driver *drv = to_ulpi_driver(dev->driver);
77 ret = of_clk_set_defaults(dev->of_node, false);
81 return drv->probe(to_ulpi_dev(dev));
84 static int ulpi_remove(struct device *dev)
86 struct ulpi_driver *drv = to_ulpi_driver(dev->driver);
89 drv->remove(to_ulpi_dev(dev));
94 static struct bus_type ulpi_bus = {
97 .uevent = ulpi_uevent,
99 .remove = ulpi_remove,
102 /* -------------------------------------------------------------------------- */
104 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
108 struct ulpi *ulpi = to_ulpi_dev(dev);
110 len = of_device_modalias(dev, buf, PAGE_SIZE);
114 return sprintf(buf, "ulpi:v%04xp%04x\n",
115 ulpi->id.vendor, ulpi->id.product);
117 static DEVICE_ATTR_RO(modalias);
119 static struct attribute *ulpi_dev_attrs[] = {
120 &dev_attr_modalias.attr,
124 static struct attribute_group ulpi_dev_attr_group = {
125 .attrs = ulpi_dev_attrs,
128 static const struct attribute_group *ulpi_dev_attr_groups[] = {
129 &ulpi_dev_attr_group,
133 static void ulpi_dev_release(struct device *dev)
135 of_node_put(dev->of_node);
136 kfree(to_ulpi_dev(dev));
139 static const struct device_type ulpi_dev_type = {
140 .name = "ulpi_device",
141 .groups = ulpi_dev_attr_groups,
142 .release = ulpi_dev_release,
145 /* -------------------------------------------------------------------------- */
148 * ulpi_register_driver - register a driver with the ULPI bus
149 * @drv: driver being registered
150 * @module: ends up being THIS_MODULE
152 * Registers a driver with the ULPI bus.
154 int __ulpi_register_driver(struct ulpi_driver *drv, struct module *module)
159 drv->driver.owner = module;
160 drv->driver.bus = &ulpi_bus;
162 return driver_register(&drv->driver);
164 EXPORT_SYMBOL_GPL(__ulpi_register_driver);
167 * ulpi_unregister_driver - unregister a driver with the ULPI bus
168 * @drv: driver to unregister
170 * Unregisters a driver with the ULPI bus.
172 void ulpi_unregister_driver(struct ulpi_driver *drv)
174 driver_unregister(&drv->driver);
176 EXPORT_SYMBOL_GPL(ulpi_unregister_driver);
178 /* -------------------------------------------------------------------------- */
180 static int ulpi_of_register(struct ulpi *ulpi)
182 struct device_node *np = NULL, *child;
183 struct device *parent;
185 /* Find a ulpi bus underneath the parent or the grandparent */
186 parent = ulpi->dev.parent;
188 np = of_get_child_by_name(parent->of_node, "ulpi");
189 else if (parent->parent && parent->parent->of_node)
190 np = of_get_child_by_name(parent->parent->of_node, "ulpi");
194 child = of_get_next_available_child(np, NULL);
199 ulpi->dev.of_node = child;
204 static int ulpi_read_id(struct ulpi *ulpi)
208 /* Test the interface */
209 ret = ulpi_write(ulpi, ULPI_SCRATCH, 0xaa);
213 ret = ulpi_read(ulpi, ULPI_SCRATCH);
220 ulpi->id.vendor = ulpi_read(ulpi, ULPI_VENDOR_ID_LOW);
221 ulpi->id.vendor |= ulpi_read(ulpi, ULPI_VENDOR_ID_HIGH) << 8;
223 ulpi->id.product = ulpi_read(ulpi, ULPI_PRODUCT_ID_LOW);
224 ulpi->id.product |= ulpi_read(ulpi, ULPI_PRODUCT_ID_HIGH) << 8;
226 /* Some ULPI devices don't have a vendor id so rely on OF match */
227 if (ulpi->id.vendor == 0)
230 request_module("ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product);
233 of_device_request_module(&ulpi->dev);
237 static int ulpi_register(struct device *dev, struct ulpi *ulpi)
241 ulpi->dev.parent = dev; /* needed early for ops */
242 ulpi->dev.bus = &ulpi_bus;
243 ulpi->dev.type = &ulpi_dev_type;
244 dev_set_name(&ulpi->dev, "%s.ulpi", dev_name(dev));
246 ACPI_COMPANION_SET(&ulpi->dev, ACPI_COMPANION(dev));
248 ret = ulpi_of_register(ulpi);
252 ret = ulpi_read_id(ulpi);
254 of_node_put(ulpi->dev.of_node);
258 ret = device_register(&ulpi->dev);
260 put_device(&ulpi->dev);
264 dev_dbg(&ulpi->dev, "registered ULPI PHY: vendor %04x, product %04x\n",
265 ulpi->id.vendor, ulpi->id.product);
271 * ulpi_register_interface - instantiate new ULPI device
272 * @dev: USB controller's device interface
273 * @ops: ULPI register access
275 * Allocates and registers a ULPI device and an interface for it. Called from
276 * the USB controller that provides the ULPI interface.
278 struct ulpi *ulpi_register_interface(struct device *dev,
279 const struct ulpi_ops *ops)
284 ulpi = kzalloc(sizeof(*ulpi), GFP_KERNEL);
286 return ERR_PTR(-ENOMEM);
290 ret = ulpi_register(dev, ulpi);
298 EXPORT_SYMBOL_GPL(ulpi_register_interface);
301 * ulpi_unregister_interface - unregister ULPI interface
302 * @ulpi: struct ulpi_interface
304 * Unregisters a ULPI device and it's interface that was created with
305 * ulpi_create_interface().
307 void ulpi_unregister_interface(struct ulpi *ulpi)
309 device_unregister(&ulpi->dev);
311 EXPORT_SYMBOL_GPL(ulpi_unregister_interface);
313 /* -------------------------------------------------------------------------- */
315 static int __init ulpi_init(void)
317 return bus_register(&ulpi_bus);
319 subsys_initcall(ulpi_init);
321 static void __exit ulpi_exit(void)
323 bus_unregister(&ulpi_bus);
325 module_exit(ulpi_exit);
327 MODULE_AUTHOR("Intel Corporation");
328 MODULE_LICENSE("GPL v2");
329 MODULE_DESCRIPTION("USB ULPI PHY bus");