Loading...
Note: File does not exist in v3.1.
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Driver for SMSC USB3503 USB 2.0 hub controller driver
4 *
5 * Copyright (c) 2012-2013 Dongjin Kim (tobetter@gmail.com)
6 */
7
8#include <linux/clk.h>
9#include <linux/i2c.h>
10#include <linux/gpio.h>
11#include <linux/delay.h>
12#include <linux/slab.h>
13#include <linux/module.h>
14#include <linux/of_gpio.h>
15#include <linux/platform_device.h>
16#include <linux/platform_data/usb3503.h>
17#include <linux/regmap.h>
18
19#define USB3503_VIDL 0x00
20#define USB3503_VIDM 0x01
21#define USB3503_PIDL 0x02
22#define USB3503_PIDM 0x03
23#define USB3503_DIDL 0x04
24#define USB3503_DIDM 0x05
25
26#define USB3503_CFG1 0x06
27#define USB3503_SELF_BUS_PWR (1 << 7)
28
29#define USB3503_CFG2 0x07
30#define USB3503_CFG3 0x08
31#define USB3503_NRD 0x09
32
33#define USB3503_PDS 0x0a
34
35#define USB3503_SP_ILOCK 0xe7
36#define USB3503_SPILOCK_CONNECT (1 << 1)
37#define USB3503_SPILOCK_CONFIG (1 << 0)
38
39#define USB3503_CFGP 0xee
40#define USB3503_CLKSUSP (1 << 7)
41
42#define USB3503_RESET 0xff
43
44struct usb3503 {
45 enum usb3503_mode mode;
46 struct regmap *regmap;
47 struct device *dev;
48 struct clk *clk;
49 u8 port_off_mask;
50 int gpio_intn;
51 int gpio_reset;
52 int gpio_connect;
53 bool secondary_ref_clk;
54};
55
56static int usb3503_reset(struct usb3503 *hub, int state)
57{
58 if (!state && gpio_is_valid(hub->gpio_connect))
59 gpio_set_value_cansleep(hub->gpio_connect, 0);
60
61 if (gpio_is_valid(hub->gpio_reset))
62 gpio_set_value_cansleep(hub->gpio_reset, state);
63
64 /* Wait T_HUBINIT == 4ms for hub logic to stabilize */
65 if (state)
66 usleep_range(4000, 10000);
67
68 return 0;
69}
70
71static int usb3503_connect(struct usb3503 *hub)
72{
73 struct device *dev = hub->dev;
74 int err;
75
76 usb3503_reset(hub, 1);
77
78 if (hub->regmap) {
79 /* SP_ILOCK: set connect_n, config_n for config */
80 err = regmap_write(hub->regmap, USB3503_SP_ILOCK,
81 (USB3503_SPILOCK_CONNECT
82 | USB3503_SPILOCK_CONFIG));
83 if (err < 0) {
84 dev_err(dev, "SP_ILOCK failed (%d)\n", err);
85 return err;
86 }
87
88 /* PDS : Set the ports which are disabled in self-powered mode. */
89 if (hub->port_off_mask) {
90 err = regmap_update_bits(hub->regmap, USB3503_PDS,
91 hub->port_off_mask,
92 hub->port_off_mask);
93 if (err < 0) {
94 dev_err(dev, "PDS failed (%d)\n", err);
95 return err;
96 }
97 }
98
99 /* CFG1 : Set SELF_BUS_PWR, this enables self-powered operation. */
100 err = regmap_update_bits(hub->regmap, USB3503_CFG1,
101 USB3503_SELF_BUS_PWR,
102 USB3503_SELF_BUS_PWR);
103 if (err < 0) {
104 dev_err(dev, "CFG1 failed (%d)\n", err);
105 return err;
106 }
107
108 /* SP_LOCK: clear connect_n, config_n for hub connect */
109 err = regmap_update_bits(hub->regmap, USB3503_SP_ILOCK,
110 (USB3503_SPILOCK_CONNECT
111 | USB3503_SPILOCK_CONFIG), 0);
112 if (err < 0) {
113 dev_err(dev, "SP_ILOCK failed (%d)\n", err);
114 return err;
115 }
116 }
117
118 if (gpio_is_valid(hub->gpio_connect))
119 gpio_set_value_cansleep(hub->gpio_connect, 1);
120
121 hub->mode = USB3503_MODE_HUB;
122 dev_info(dev, "switched to HUB mode\n");
123
124 return 0;
125}
126
127static int usb3503_switch_mode(struct usb3503 *hub, enum usb3503_mode mode)
128{
129 struct device *dev = hub->dev;
130 int err = 0;
131
132 switch (mode) {
133 case USB3503_MODE_HUB:
134 err = usb3503_connect(hub);
135 break;
136
137 case USB3503_MODE_STANDBY:
138 usb3503_reset(hub, 0);
139 dev_info(dev, "switched to STANDBY mode\n");
140 break;
141
142 default:
143 dev_err(dev, "unknown mode is requested\n");
144 err = -EINVAL;
145 break;
146 }
147
148 return err;
149}
150
151static const struct regmap_config usb3503_regmap_config = {
152 .reg_bits = 8,
153 .val_bits = 8,
154
155 .max_register = USB3503_RESET,
156};
157
158static int usb3503_probe(struct usb3503 *hub)
159{
160 struct device *dev = hub->dev;
161 struct usb3503_platform_data *pdata = dev_get_platdata(dev);
162 struct device_node *np = dev->of_node;
163 int err;
164 u32 mode = USB3503_MODE_HUB;
165 const u32 *property;
166 int len;
167
168 if (pdata) {
169 hub->port_off_mask = pdata->port_off_mask;
170 hub->gpio_intn = pdata->gpio_intn;
171 hub->gpio_connect = pdata->gpio_connect;
172 hub->gpio_reset = pdata->gpio_reset;
173 hub->mode = pdata->initial_mode;
174 } else if (np) {
175 struct clk *clk;
176 u32 rate = 0;
177 hub->port_off_mask = 0;
178
179 if (!of_property_read_u32(np, "refclk-frequency", &rate)) {
180 switch (rate) {
181 case 38400000:
182 case 26000000:
183 case 19200000:
184 case 12000000:
185 hub->secondary_ref_clk = 0;
186 break;
187 case 24000000:
188 case 27000000:
189 case 25000000:
190 case 50000000:
191 hub->secondary_ref_clk = 1;
192 break;
193 default:
194 dev_err(dev,
195 "unsupported reference clock rate (%d)\n",
196 (int) rate);
197 return -EINVAL;
198 }
199 }
200
201 clk = devm_clk_get(dev, "refclk");
202 if (IS_ERR(clk) && PTR_ERR(clk) != -ENOENT) {
203 dev_err(dev, "unable to request refclk (%ld)\n",
204 PTR_ERR(clk));
205 return PTR_ERR(clk);
206 }
207
208 if (!IS_ERR(clk)) {
209 hub->clk = clk;
210
211 if (rate != 0) {
212 err = clk_set_rate(hub->clk, rate);
213 if (err) {
214 dev_err(dev,
215 "unable to set reference clock rate to %d\n",
216 (int) rate);
217 return err;
218 }
219 }
220
221 err = clk_prepare_enable(hub->clk);
222 if (err) {
223 dev_err(dev,
224 "unable to enable reference clock\n");
225 return err;
226 }
227 }
228
229 property = of_get_property(np, "disabled-ports", &len);
230 if (property && (len / sizeof(u32)) > 0) {
231 int i;
232 for (i = 0; i < len / sizeof(u32); i++) {
233 u32 port = be32_to_cpu(property[i]);
234 if ((1 <= port) && (port <= 3))
235 hub->port_off_mask |= (1 << port);
236 }
237 }
238
239 hub->gpio_intn = of_get_named_gpio(np, "intn-gpios", 0);
240 if (hub->gpio_intn == -EPROBE_DEFER)
241 return -EPROBE_DEFER;
242 hub->gpio_connect = of_get_named_gpio(np, "connect-gpios", 0);
243 if (hub->gpio_connect == -EPROBE_DEFER)
244 return -EPROBE_DEFER;
245 hub->gpio_reset = of_get_named_gpio(np, "reset-gpios", 0);
246 if (hub->gpio_reset == -EPROBE_DEFER)
247 return -EPROBE_DEFER;
248 of_property_read_u32(np, "initial-mode", &mode);
249 hub->mode = mode;
250 }
251
252 if (hub->port_off_mask && !hub->regmap)
253 dev_err(dev, "Ports disabled with no control interface\n");
254
255 if (gpio_is_valid(hub->gpio_intn)) {
256 int val = hub->secondary_ref_clk ? GPIOF_OUT_INIT_LOW :
257 GPIOF_OUT_INIT_HIGH;
258 err = devm_gpio_request_one(dev, hub->gpio_intn, val,
259 "usb3503 intn");
260 if (err) {
261 dev_err(dev,
262 "unable to request GPIO %d as interrupt pin (%d)\n",
263 hub->gpio_intn, err);
264 return err;
265 }
266 }
267
268 if (gpio_is_valid(hub->gpio_connect)) {
269 err = devm_gpio_request_one(dev, hub->gpio_connect,
270 GPIOF_OUT_INIT_LOW, "usb3503 connect");
271 if (err) {
272 dev_err(dev,
273 "unable to request GPIO %d as connect pin (%d)\n",
274 hub->gpio_connect, err);
275 return err;
276 }
277 }
278
279 if (gpio_is_valid(hub->gpio_reset)) {
280 err = devm_gpio_request_one(dev, hub->gpio_reset,
281 GPIOF_OUT_INIT_LOW, "usb3503 reset");
282 /* Datasheet defines a hardware reset to be at least 100us */
283 usleep_range(100, 10000);
284 if (err) {
285 dev_err(dev,
286 "unable to request GPIO %d as reset pin (%d)\n",
287 hub->gpio_reset, err);
288 return err;
289 }
290 }
291
292 usb3503_switch_mode(hub, hub->mode);
293
294 dev_info(dev, "%s: probed in %s mode\n", __func__,
295 (hub->mode == USB3503_MODE_HUB) ? "hub" : "standby");
296
297 return 0;
298}
299
300static int usb3503_i2c_probe(struct i2c_client *i2c,
301 const struct i2c_device_id *id)
302{
303 struct usb3503 *hub;
304 int err;
305
306 hub = devm_kzalloc(&i2c->dev, sizeof(struct usb3503), GFP_KERNEL);
307 if (!hub)
308 return -ENOMEM;
309
310 i2c_set_clientdata(i2c, hub);
311 hub->regmap = devm_regmap_init_i2c(i2c, &usb3503_regmap_config);
312 if (IS_ERR(hub->regmap)) {
313 err = PTR_ERR(hub->regmap);
314 dev_err(&i2c->dev, "Failed to initialise regmap: %d\n", err);
315 return err;
316 }
317 hub->dev = &i2c->dev;
318
319 return usb3503_probe(hub);
320}
321
322static int usb3503_i2c_remove(struct i2c_client *i2c)
323{
324 struct usb3503 *hub;
325
326 hub = i2c_get_clientdata(i2c);
327 if (hub->clk)
328 clk_disable_unprepare(hub->clk);
329
330 return 0;
331}
332
333static int usb3503_platform_probe(struct platform_device *pdev)
334{
335 struct usb3503 *hub;
336
337 hub = devm_kzalloc(&pdev->dev, sizeof(struct usb3503), GFP_KERNEL);
338 if (!hub)
339 return -ENOMEM;
340 hub->dev = &pdev->dev;
341 platform_set_drvdata(pdev, hub);
342
343 return usb3503_probe(hub);
344}
345
346static int usb3503_platform_remove(struct platform_device *pdev)
347{
348 struct usb3503 *hub;
349
350 hub = platform_get_drvdata(pdev);
351 if (hub->clk)
352 clk_disable_unprepare(hub->clk);
353
354 return 0;
355}
356
357#ifdef CONFIG_PM_SLEEP
358static int usb3503_i2c_suspend(struct device *dev)
359{
360 struct i2c_client *client = to_i2c_client(dev);
361 struct usb3503 *hub = i2c_get_clientdata(client);
362
363 usb3503_switch_mode(hub, USB3503_MODE_STANDBY);
364
365 if (hub->clk)
366 clk_disable_unprepare(hub->clk);
367
368 return 0;
369}
370
371static int usb3503_i2c_resume(struct device *dev)
372{
373 struct i2c_client *client = to_i2c_client(dev);
374 struct usb3503 *hub = i2c_get_clientdata(client);
375
376 if (hub->clk)
377 clk_prepare_enable(hub->clk);
378
379 usb3503_switch_mode(hub, hub->mode);
380
381 return 0;
382}
383#endif
384
385static SIMPLE_DEV_PM_OPS(usb3503_i2c_pm_ops, usb3503_i2c_suspend,
386 usb3503_i2c_resume);
387
388static const struct i2c_device_id usb3503_id[] = {
389 { USB3503_I2C_NAME, 0 },
390 { }
391};
392MODULE_DEVICE_TABLE(i2c, usb3503_id);
393
394#ifdef CONFIG_OF
395static const struct of_device_id usb3503_of_match[] = {
396 { .compatible = "smsc,usb3503", },
397 { .compatible = "smsc,usb3503a", },
398 {},
399};
400MODULE_DEVICE_TABLE(of, usb3503_of_match);
401#endif
402
403static struct i2c_driver usb3503_i2c_driver = {
404 .driver = {
405 .name = USB3503_I2C_NAME,
406 .pm = &usb3503_i2c_pm_ops,
407 .of_match_table = of_match_ptr(usb3503_of_match),
408 },
409 .probe = usb3503_i2c_probe,
410 .remove = usb3503_i2c_remove,
411 .id_table = usb3503_id,
412};
413
414static struct platform_driver usb3503_platform_driver = {
415 .driver = {
416 .name = USB3503_I2C_NAME,
417 .of_match_table = of_match_ptr(usb3503_of_match),
418 },
419 .probe = usb3503_platform_probe,
420 .remove = usb3503_platform_remove,
421};
422
423static int __init usb3503_init(void)
424{
425 int err;
426
427 err = i2c_add_driver(&usb3503_i2c_driver);
428 if (err != 0)
429 pr_err("usb3503: Failed to register I2C driver: %d\n", err);
430
431 err = platform_driver_register(&usb3503_platform_driver);
432 if (err != 0)
433 pr_err("usb3503: Failed to register platform driver: %d\n",
434 err);
435
436 return 0;
437}
438module_init(usb3503_init);
439
440static void __exit usb3503_exit(void)
441{
442 platform_driver_unregister(&usb3503_platform_driver);
443 i2c_del_driver(&usb3503_i2c_driver);
444}
445module_exit(usb3503_exit);
446
447MODULE_AUTHOR("Dongjin Kim <tobetter@gmail.com>");
448MODULE_DESCRIPTION("USB3503 USB HUB driver");
449MODULE_LICENSE("GPL");