summaryrefslogtreecommitdiff
path: root/drivers/usb/misc/usb3503.c
blob: ae7e1206ca541aa90dcca8b9c15b601fa4fc1d78 (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
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
/*
 * Driver for SMSC USB3503 USB 2.0 hub controller driver
 *
 * Copyright (c) 2012-2013 Dongjin Kim (tobetter@gmail.com)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/clk.h>
#include <linux/i2c.h>
#include <linux/gpio.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/of_gpio.h>
#include <linux/platform_device.h>
#include <linux/platform_data/usb3503.h>
#include <linux/regmap.h>

#define USB3503_VIDL		0x00
#define USB3503_VIDM		0x01
#define USB3503_PIDL		0x02
#define USB3503_PIDM		0x03
#define USB3503_DIDL		0x04
#define USB3503_DIDM		0x05

#define USB3503_CFG1		0x06
#define USB3503_SELF_BUS_PWR	(1 << 7)

#define USB3503_CFG2		0x07
#define USB3503_CFG3		0x08
#define USB3503_NRD		0x09

#define USB3503_PDS		0x0a

#define USB3503_SP_ILOCK	0xe7
#define USB3503_SPILOCK_CONNECT	(1 << 1)
#define USB3503_SPILOCK_CONFIG	(1 << 0)

#define USB3503_CFGP		0xee
#define USB3503_CLKSUSP		(1 << 7)

#define USB3503_RESET		0xff

struct usb3503 {
	enum usb3503_mode	mode;
	struct regmap		*regmap;
	struct device		*dev;
	struct clk		*clk;
	u8	port_off_mask;
	int	gpio_intn;
	int	gpio_reset;
	int	gpio_connect;
	bool	secondary_ref_clk;
};

static int usb3503_reset(struct usb3503 *hub, int state)
{
	if (!state && gpio_is_valid(hub->gpio_connect))
		gpio_set_value_cansleep(hub->gpio_connect, 0);

	if (gpio_is_valid(hub->gpio_reset))
		gpio_set_value_cansleep(hub->gpio_reset, state);

	/* Wait T_HUBINIT == 4ms for hub logic to stabilize */
	if (state)
		usleep_range(4000, 10000);

	return 0;
}

static int usb3503_connect(struct usb3503 *hub)
{
	struct device *dev = hub->dev;
	int err;

	usb3503_reset(hub, 1);

	if (hub->regmap) {
		/* SP_ILOCK: set connect_n, config_n for config */
		err = regmap_write(hub->regmap, USB3503_SP_ILOCK,
			   (USB3503_SPILOCK_CONNECT
				 | USB3503_SPILOCK_CONFIG));
		if (err < 0) {
			dev_err(dev, "SP_ILOCK failed (%d)\n", err);
			return err;
		}

		/* PDS : Set the ports which are disabled in self-powered mode. */
		if (hub->port_off_mask) {
			err = regmap_update_bits(hub->regmap, USB3503_PDS,
					hub->port_off_mask,
					hub->port_off_mask);
			if (err < 0) {
				dev_err(dev, "PDS failed (%d)\n", err);
				return err;
			}
		}

		/* CFG1 : Set SELF_BUS_PWR, this enables self-powered operation. */
		err = regmap_update_bits(hub->regmap, USB3503_CFG1,
					 USB3503_SELF_BUS_PWR,
					 USB3503_SELF_BUS_PWR);
		if (err < 0) {
			dev_err(dev, "CFG1 failed (%d)\n", err);
			return err;
		}

		/* SP_LOCK: clear connect_n, config_n for hub connect */
		err = regmap_update_bits(hub->regmap, USB3503_SP_ILOCK,
					 (USB3503_SPILOCK_CONNECT
					  | USB3503_SPILOCK_CONFIG), 0);
		if (err < 0) {
			dev_err(dev, "SP_ILOCK failed (%d)\n", err);
			return err;
		}
	}

	if (gpio_is_valid(hub->gpio_connect))
		gpio_set_value_cansleep(hub->gpio_connect, 1);

	hub->mode = USB3503_MODE_HUB;
	dev_info(dev, "switched to HUB mode\n");

	return 0;
}

static int usb3503_switch_mode(struct usb3503 *hub, enum usb3503_mode mode)
{
	struct device *dev = hub->dev;
	int err = 0;

	switch (mode) {
	case USB3503_MODE_HUB:
		err = usb3503_connect(hub);
		break;

	case USB3503_MODE_STANDBY:
		usb3503_reset(hub, 0);
		dev_info(dev, "switched to STANDBY mode\n");
		break;

	default:
		dev_err(dev, "unknown mode is requested\n");
		err = -EINVAL;
		break;
	}

	return err;
}

static const struct regmap_config usb3503_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,

	.max_register = USB3503_RESET,
};

static int usb3503_probe(struct usb3503 *hub)
{
	struct device *dev = hub->dev;
	struct usb3503_platform_data *pdata = dev_get_platdata(dev);
	struct device_node *np = dev->of_node;
	int err;
	u32 mode = USB3503_MODE_HUB;
	const u32 *property;
	int len;

	if (pdata) {
		hub->port_off_mask	= pdata->port_off_mask;
		hub->gpio_intn		= pdata->gpio_intn;
		hub->gpio_connect	= pdata->gpio_connect;
		hub->gpio_reset		= pdata->gpio_reset;
		hub->mode		= pdata->initial_mode;
	} else if (np) {
		struct clk *clk;
		hub->port_off_mask = 0;

		clk = devm_clk_get(dev, "refclk");
		if (IS_ERR(clk) && PTR_ERR(clk) != -ENOENT) {
			dev_err(dev, "unable to request refclk (%ld)\n",
					PTR_ERR(clk));
			return PTR_ERR(clk);
		}

		if (!IS_ERR(clk)) {
			u32 rate = 0;
			hub->clk = clk;

			if (!of_property_read_u32(np, "refclk-frequency",
						 &rate)) {

				switch (rate) {
				case 38400000:
				case 26000000:
				case 19200000:
				case 12000000:
					hub->secondary_ref_clk = 0;
					break;
				case 24000000:
				case 27000000:
				case 25000000:
				case 50000000:
					hub->secondary_ref_clk = 1;
					break;
				default:
					dev_err(dev,
						"unsupported reference clock rate (%d)\n",
						(int) rate);
					return -EINVAL;
				}
				err = clk_set_rate(hub->clk, rate);
				if (err) {
					dev_err(dev,
						"unable to set reference clock rate to %d\n",
						(int) rate);
					return err;
				}
			}

			err = clk_prepare_enable(hub->clk);
			if (err) {
				dev_err(dev,
					"unable to enable reference clock\n");
				return err;
			}
		}

		property = of_get_property(np, "disabled-ports", &len);
		if (property && (len / sizeof(u32)) > 0) {
			int i;
			for (i = 0; i < len / sizeof(u32); i++) {
				u32 port = be32_to_cpu(property[i]);
				if ((1 <= port) && (port <= 3))
					hub->port_off_mask |= (1 << port);
			}
		}

		hub->gpio_intn	= of_get_named_gpio(np, "intn-gpios", 0);
		if (hub->gpio_intn == -EPROBE_DEFER)
			return -EPROBE_DEFER;
		hub->gpio_connect = of_get_named_gpio(np, "connect-gpios", 0);
		if (hub->gpio_connect == -EPROBE_DEFER)
			return -EPROBE_DEFER;
		hub->gpio_reset = of_get_named_gpio(np, "reset-gpios", 0);
		if (hub->gpio_reset == -EPROBE_DEFER)
			return -EPROBE_DEFER;
		of_property_read_u32(np, "initial-mode", &mode);
		hub->mode = mode;
	}

	if (hub->port_off_mask && !hub->regmap)
		dev_err(dev, "Ports disabled with no control interface\n");

	if (gpio_is_valid(hub->gpio_intn)) {
		int val = hub->secondary_ref_clk ? GPIOF_OUT_INIT_LOW :
						   GPIOF_OUT_INIT_HIGH;
		err = devm_gpio_request_one(dev, hub->gpio_intn, val,
					    "usb3503 intn");
		if (err) {
			dev_err(dev,
				"unable to request GPIO %d as interrupt pin (%d)\n",
				hub->gpio_intn, err);
			return err;
		}
	}

	if (gpio_is_valid(hub->gpio_connect)) {
		err = devm_gpio_request_one(dev, hub->gpio_connect,
				GPIOF_OUT_INIT_LOW, "usb3503 connect");
		if (err) {
			dev_err(dev,
				"unable to request GPIO %d as connect pin (%d)\n",
				hub->gpio_connect, err);
			return err;
		}
	}

	if (gpio_is_valid(hub->gpio_reset)) {
		err = devm_gpio_request_one(dev, hub->gpio_reset,
				GPIOF_OUT_INIT_LOW, "usb3503 reset");
		if (err) {
			dev_err(dev,
				"unable to request GPIO %d as reset pin (%d)\n",
				hub->gpio_reset, err);
			return err;
		}
	}

	usb3503_switch_mode(hub, hub->mode);

	dev_info(dev, "%s: probed in %s mode\n", __func__,
			(hub->mode == USB3503_MODE_HUB) ? "hub" : "standby");

	return 0;
}

static int usb3503_i2c_probe(struct i2c_client *i2c,
			     const struct i2c_device_id *id)
{
	struct usb3503 *hub;
	int err;

	hub = devm_kzalloc(&i2c->dev, sizeof(struct usb3503), GFP_KERNEL);
	if (!hub) {
		dev_err(&i2c->dev, "private data alloc fail\n");
		return -ENOMEM;
	}

	i2c_set_clientdata(i2c, hub);
	hub->regmap = devm_regmap_init_i2c(i2c, &usb3503_regmap_config);
	if (IS_ERR(hub->regmap)) {
		err = PTR_ERR(hub->regmap);
		dev_err(&i2c->dev, "Failed to initialise regmap: %d\n", err);
		return err;
	}
	hub->dev = &i2c->dev;

	return usb3503_probe(hub);
}

static int usb3503_platform_probe(struct platform_device *pdev)
{
	struct usb3503 *hub;

	hub = devm_kzalloc(&pdev->dev, sizeof(struct usb3503), GFP_KERNEL);
	if (!hub) {
		dev_err(&pdev->dev, "private data alloc fail\n");
		return -ENOMEM;
	}
	hub->dev = &pdev->dev;

	return usb3503_probe(hub);
}

#ifdef CONFIG_PM_SLEEP
static int usb3503_i2c_suspend(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct usb3503 *hub = i2c_get_clientdata(client);

	usb3503_switch_mode(hub, USB3503_MODE_STANDBY);

	if (hub->clk)
		clk_disable_unprepare(hub->clk);

	return 0;
}

static int usb3503_i2c_resume(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct usb3503 *hub = i2c_get_clientdata(client);

	if (hub->clk)
		clk_prepare_enable(hub->clk);

	usb3503_switch_mode(hub, hub->mode);

	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(usb3503_i2c_pm_ops, usb3503_i2c_suspend,
		usb3503_i2c_resume);

static const struct i2c_device_id usb3503_id[] = {
	{ USB3503_I2C_NAME, 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, usb3503_id);

#ifdef CONFIG_OF
static const struct of_device_id usb3503_of_match[] = {
	{ .compatible = "smsc,usb3503", },
	{ .compatible = "smsc,usb3503a", },
	{},
};
MODULE_DEVICE_TABLE(of, usb3503_of_match);
#endif

static struct i2c_driver usb3503_i2c_driver = {
	.driver = {
		.name = USB3503_I2C_NAME,
		.pm = &usb3503_i2c_pm_ops,
		.of_match_table = of_match_ptr(usb3503_of_match),
	},
	.probe		= usb3503_i2c_probe,
	.id_table	= usb3503_id,
};

static struct platform_driver usb3503_platform_driver = {
	.driver = {
		.name = USB3503_I2C_NAME,
		.of_match_table = of_match_ptr(usb3503_of_match),
		.owner = THIS_MODULE,
	},
	.probe		= usb3503_platform_probe,
};

static int __init usb3503_init(void)
{
	int err;

	err = i2c_register_driver(THIS_MODULE, &usb3503_i2c_driver);
	if (err != 0)
		pr_err("usb3503: Failed to register I2C driver: %d\n", err);

	err = platform_driver_register(&usb3503_platform_driver);
	if (err != 0)
		pr_err("usb3503: Failed to register platform driver: %d\n",
		       err);

	return 0;
}
module_init(usb3503_init);

static void __exit usb3503_exit(void)
{
	platform_driver_unregister(&usb3503_platform_driver);
	i2c_del_driver(&usb3503_i2c_driver);
}
module_exit(usb3503_exit);

MODULE_AUTHOR("Dongjin Kim <tobetter@gmail.com>");
MODULE_DESCRIPTION("USB3503 USB HUB driver");
MODULE_LICENSE("GPL");