summaryrefslogtreecommitdiffstats
path: root/drivers/usb/common/ulpi.c
blob: ce5e6f6711f795e49c1c78ccac0770f5790ae9c0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
// SPDX-License-Identifier: GPL-2.0
/*
 * ulpi.c - USB ULPI PHY bus
 *
 * Copyright (C) 2015 Intel Corporation
 *
 * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
 */

#include <linux/ulpi/interface.h>
#include <linux/ulpi/driver.h>
#include <linux/ulpi/regs.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/acpi.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/clk/clk-conf.h>

/* -------------------------------------------------------------------------- */

int ulpi_read(struct ulpi *ulpi, u8 addr)
{
	return ulpi->ops->read(ulpi->dev.parent, addr);
}
EXPORT_SYMBOL_GPL(ulpi_read);

int ulpi_write(struct ulpi *ulpi, u8 addr, u8 val)
{
	return ulpi->ops->write(ulpi->dev.parent, addr, val);
}
EXPORT_SYMBOL_GPL(ulpi_write);

/* -------------------------------------------------------------------------- */

static int ulpi_match(struct device *dev, struct device_driver *driver)
{
	struct ulpi_driver *drv = to_ulpi_driver(driver);
	struct ulpi *ulpi = to_ulpi_dev(dev);
	const struct ulpi_device_id *id;

	/* Some ULPI devices don't have a vendor id so rely on OF match */
	if (ulpi->id.vendor == 0)
		return of_driver_match_device(dev, driver);

	for (id = drv->id_table; id->vendor; id++)
		if (id->vendor == ulpi->id.vendor &&
		    id->product == ulpi->id.product)
			return 1;

	return 0;
}

static int ulpi_uevent(struct device *dev, struct kobj_uevent_env *env)
{
	struct ulpi *ulpi = to_ulpi_dev(dev);
	int ret;

	ret = of_device_uevent_modalias(dev, env);
	if (ret != -ENODEV)
		return ret;

	if (add_uevent_var(env, "MODALIAS=ulpi:v%04xp%04x",
			   ulpi->id.vendor, ulpi->id.product))
		return -ENOMEM;
	return 0;
}

static int ulpi_probe(struct device *dev)
{
	struct ulpi_driver *drv = to_ulpi_driver(dev->driver);
	int ret;

	ret = of_clk_set_defaults(dev->of_node, false);
	if (ret < 0)
		return ret;

	return drv->probe(to_ulpi_dev(dev));
}

static int ulpi_remove(struct device *dev)
{
	struct ulpi_driver *drv = to_ulpi_driver(dev->driver);

	if (drv->remove)
		drv->remove(to_ulpi_dev(dev));

	return 0;
}

static struct bus_type ulpi_bus = {
	.name = "ulpi",
	.match = ulpi_match,
	.uevent = ulpi_uevent,
	.probe = ulpi_probe,
	.remove = ulpi_remove,
};

/* -------------------------------------------------------------------------- */

static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
			     char *buf)
{
	int len;
	struct ulpi *ulpi = to_ulpi_dev(dev);

	len = of_device_modalias(dev, buf, PAGE_SIZE);
	if (len != -ENODEV)
		return len;

	return sprintf(buf, "ulpi:v%04xp%04x\n",
		       ulpi->id.vendor, ulpi->id.product);
}
static DEVICE_ATTR_RO(modalias);

static struct attribute *ulpi_dev_attrs[] = {
	&dev_attr_modalias.attr,
	NULL
};

static const struct attribute_group ulpi_dev_attr_group = {
	.attrs = ulpi_dev_attrs,
};

static const struct attribute_group *ulpi_dev_attr_groups[] = {
	&ulpi_dev_attr_group,
	NULL
};

static void ulpi_dev_release(struct device *dev)
{
	kfree(to_ulpi_dev(dev));
}

static const struct device_type ulpi_dev_type = {
	.name = "ulpi_device",
	.groups = ulpi_dev_attr_groups,
	.release = ulpi_dev_release,
};

/* -------------------------------------------------------------------------- */

/**
 * ulpi_register_driver - register a driver with the ULPI bus
 * @drv: driver being registered
 * @module: ends up being THIS_MODULE
 *
 * Registers a driver with the ULPI bus.
 */
int __ulpi_register_driver(struct ulpi_driver *drv, struct module *module)
{
	if (!drv->probe)
		return -EINVAL;

	drv->driver.owner = module;
	drv->driver.bus = &ulpi_bus;

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

/**
 * ulpi_unregister_driver - unregister a driver with the ULPI bus
 * @drv: driver to unregister
 *
 * Unregisters a driver with the ULPI bus.
 */
void ulpi_unregister_driver(struct ulpi_driver *drv)
{
	driver_unregister(&drv->driver);
}
EXPORT_SYMBOL_GPL(ulpi_unregister_driver);

/* -------------------------------------------------------------------------- */

static int ulpi_of_register(struct ulpi *ulpi)
{
	struct device_node *np = NULL, *child;
	struct device *parent;

	/* Find a ulpi bus underneath the parent or the grandparent */
	parent = ulpi->dev.parent;
	if (parent->of_node)
		np = of_get_child_by_name(parent->of_node, "ulpi");
	else if (parent->parent && parent->parent->of_node)
		np = of_get_child_by_name(parent->parent->of_node, "ulpi");
	if (!np)
		return 0;

	child = of_get_next_available_child(np, NULL);
	of_node_put(np);
	if (!child)
		return -EINVAL;

	ulpi->dev.of_node = child;

	return 0;
}

static int ulpi_read_id(struct ulpi *ulpi)
{
	int ret;

	/* Test the interface */
	ret = ulpi_write(ulpi, ULPI_SCRATCH, 0xaa);
	if (ret < 0)
		goto err;

	ret = ulpi_read(ulpi, ULPI_SCRATCH);
	if (ret < 0)
		return ret;

	if (ret != 0xaa)
		goto err;

	ulpi->id.vendor = ulpi_read(ulpi, ULPI_VENDOR_ID_LOW);
	ulpi->id.vendor |= ulpi_read(ulpi, ULPI_VENDOR_ID_HIGH) << 8;

	ulpi->id.product = ulpi_read(ulpi, ULPI_PRODUCT_ID_LOW);
	ulpi->id.product |= ulpi_read(ulpi, ULPI_PRODUCT_ID_HIGH) << 8;

	/* Some ULPI devices don't have a vendor id so rely on OF match */
	if (ulpi->id.vendor == 0)
		goto err;

	request_module("ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product);
	return 0;
err:
	of_device_request_module(&ulpi->dev);
	return 0;
}

static int ulpi_register(struct device *dev, struct ulpi *ulpi)
{
	int ret;

	ulpi->dev.parent = dev; /* needed early for ops */
	ulpi->dev.bus = &ulpi_bus;
	ulpi->dev.type = &ulpi_dev_type;
	dev_set_name(&ulpi->dev, "%s.ulpi", dev_name(dev));

	ACPI_COMPANION_SET(&ulpi->dev, ACPI_COMPANION(dev));

	ret = ulpi_of_register(ulpi);
	if (ret)
		return ret;

	ret = ulpi_read_id(ulpi);
	if (ret)
		return ret;

	ret = device_register(&ulpi->dev);
	if (ret)
		return ret;

	dev_dbg(&ulpi->dev, "registered ULPI PHY: vendor %04x, product %04x\n",
		ulpi->id.vendor, ulpi->id.product);

	return 0;
}

/**
 * ulpi_register_interface - instantiate new ULPI device
 * @dev: USB controller's device interface
 * @ops: ULPI register access
 *
 * Allocates and registers a ULPI device and an interface for it. Called from
 * the USB controller that provides the ULPI interface.
 */
struct ulpi *ulpi_register_interface(struct device *dev,
				     const struct ulpi_ops *ops)
{
	struct ulpi *ulpi;
	int ret;

	ulpi = kzalloc(sizeof(*ulpi), GFP_KERNEL);
	if (!ulpi)
		return ERR_PTR(-ENOMEM);

	ulpi->ops = ops;

	ret = ulpi_register(dev, ulpi);
	if (ret) {
		kfree(ulpi);
		return ERR_PTR(ret);
	}

	return ulpi;
}
EXPORT_SYMBOL_GPL(ulpi_register_interface);

/**
 * ulpi_unregister_interface - unregister ULPI interface
 * @ulpi: struct ulpi_interface
 *
 * Unregisters a ULPI device and it's interface that was created with
 * ulpi_create_interface().
 */
void ulpi_unregister_interface(struct ulpi *ulpi)
{
	of_node_put(ulpi->dev.of_node);
	device_unregister(&ulpi->dev);
}
EXPORT_SYMBOL_GPL(ulpi_unregister_interface);

/* -------------------------------------------------------------------------- */

static int __init ulpi_init(void)
{
	return bus_register(&ulpi_bus);
}
subsys_initcall(ulpi_init);

static void __exit ulpi_exit(void)
{
	bus_unregister(&ulpi_bus);
}
module_exit(ulpi_exit);

MODULE_AUTHOR("Intel Corporation");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("USB ULPI PHY bus");