xref: /openbmc/linux/drivers/usb/misc/usb251xb.c (revision 2fa5ebe3)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Driver for Microchip USB251xB USB 2.0 Hi-Speed Hub Controller
4  * Configuration via SMBus.
5  *
6  * Copyright (c) 2017 SKIDATA AG
7  *
8  * This work is based on the USB3503 driver by Dongjin Kim and
9  * a not-accepted patch by Fabien Lahoudere, see:
10  * https://patchwork.kernel.org/patch/9257715/
11  */
12 
13 #include <linux/delay.h>
14 #include <linux/gpio/consumer.h>
15 #include <linux/gpio/driver.h>
16 #include <linux/i2c.h>
17 #include <linux/module.h>
18 #include <linux/nls.h>
19 #include <linux/of_device.h>
20 #include <linux/regulator/consumer.h>
21 #include <linux/slab.h>
22 
23 /* Internal Register Set Addresses & Default Values acc. to DS00001692C */
24 #define USB251XB_ADDR_VENDOR_ID_LSB	0x00
25 #define USB251XB_ADDR_VENDOR_ID_MSB	0x01
26 #define USB251XB_DEF_VENDOR_ID		0x0424
27 
28 #define USB251XB_ADDR_PRODUCT_ID_LSB	0x02
29 #define USB251XB_ADDR_PRODUCT_ID_MSB	0x03
30 
31 #define USB251XB_ADDR_DEVICE_ID_LSB	0x04
32 #define USB251XB_ADDR_DEVICE_ID_MSB	0x05
33 #define USB251XB_DEF_DEVICE_ID		0x0BB3
34 
35 #define USB251XB_ADDR_CONFIG_DATA_1	0x06
36 #define USB251XB_DEF_CONFIG_DATA_1	0x9B
37 #define USB251XB_ADDR_CONFIG_DATA_2	0x07
38 #define USB251XB_DEF_CONFIG_DATA_2	0x20
39 #define USB251XB_ADDR_CONFIG_DATA_3	0x08
40 #define USB251XB_DEF_CONFIG_DATA_3	0x02
41 
42 #define USB251XB_ADDR_NON_REMOVABLE_DEVICES	0x09
43 #define USB251XB_DEF_NON_REMOVABLE_DEVICES	0x00
44 
45 #define USB251XB_ADDR_PORT_DISABLE_SELF	0x0A
46 #define USB251XB_DEF_PORT_DISABLE_SELF	0x00
47 #define USB251XB_ADDR_PORT_DISABLE_BUS	0x0B
48 #define USB251XB_DEF_PORT_DISABLE_BUS	0x00
49 
50 #define USB251XB_ADDR_MAX_POWER_SELF	0x0C
51 #define USB251XB_DEF_MAX_POWER_SELF	0x01
52 #define USB251XB_ADDR_MAX_POWER_BUS	0x0D
53 #define USB251XB_DEF_MAX_POWER_BUS	0x32
54 
55 #define USB251XB_ADDR_MAX_CURRENT_SELF	0x0E
56 #define USB251XB_DEF_MAX_CURRENT_SELF	0x01
57 #define USB251XB_ADDR_MAX_CURRENT_BUS	0x0F
58 #define USB251XB_DEF_MAX_CURRENT_BUS	0x32
59 
60 #define USB251XB_ADDR_POWER_ON_TIME	0x10
61 #define USB251XB_DEF_POWER_ON_TIME	0x32
62 
63 #define USB251XB_ADDR_LANGUAGE_ID_HIGH	0x11
64 #define USB251XB_ADDR_LANGUAGE_ID_LOW	0x12
65 #define USB251XB_DEF_LANGUAGE_ID	0x0000
66 
67 #define USB251XB_STRING_BUFSIZE			62
68 #define USB251XB_ADDR_MANUFACTURER_STRING_LEN	0x13
69 #define USB251XB_ADDR_MANUFACTURER_STRING	0x16
70 #define USB251XB_DEF_MANUFACTURER_STRING	"Microchip"
71 
72 #define USB251XB_ADDR_PRODUCT_STRING_LEN	0x14
73 #define USB251XB_ADDR_PRODUCT_STRING		0x54
74 
75 #define USB251XB_ADDR_SERIAL_STRING_LEN		0x15
76 #define USB251XB_ADDR_SERIAL_STRING		0x92
77 #define USB251XB_DEF_SERIAL_STRING		""
78 
79 #define USB251XB_ADDR_BATTERY_CHARGING_ENABLE	0xD0
80 #define USB251XB_DEF_BATTERY_CHARGING_ENABLE	0x00
81 
82 #define USB251XB_ADDR_BOOST_UP	0xF6
83 #define USB251XB_DEF_BOOST_UP	0x00
84 #define USB251XB_ADDR_BOOST_57	0xF7
85 #define USB251XB_DEF_BOOST_57	0x00
86 #define USB251XB_ADDR_BOOST_14	0xF8
87 #define USB251XB_DEF_BOOST_14	0x00
88 
89 #define USB251XB_ADDR_PORT_SWAP	0xFA
90 #define USB251XB_DEF_PORT_SWAP	0x00
91 
92 #define USB251XB_ADDR_PORT_MAP_12	0xFB
93 #define USB251XB_DEF_PORT_MAP_12	0x00
94 #define USB251XB_ADDR_PORT_MAP_34	0xFC
95 #define USB251XB_DEF_PORT_MAP_34	0x00 /* USB251{3B/i,4B/i,7/i} only */
96 #define USB251XB_ADDR_PORT_MAP_56	0xFD
97 #define USB251XB_DEF_PORT_MAP_56	0x00 /* USB2517/i only */
98 #define USB251XB_ADDR_PORT_MAP_7	0xFE
99 #define USB251XB_DEF_PORT_MAP_7		0x00 /* USB2517/i only */
100 
101 #define USB251XB_ADDR_STATUS_COMMAND		0xFF
102 #define USB251XB_STATUS_COMMAND_SMBUS_DOWN	0x04
103 #define USB251XB_STATUS_COMMAND_RESET		0x02
104 #define USB251XB_STATUS_COMMAND_ATTACH		0x01
105 
106 #define USB251XB_I2C_REG_SZ	0x100
107 #define USB251XB_I2C_WRITE_SZ	0x10
108 
109 #define DRIVER_NAME	"usb251xb"
110 #define DRIVER_DESC	"Microchip USB 2.0 Hi-Speed Hub Controller"
111 
112 struct usb251xb {
113 	struct device *dev;
114 	struct i2c_client *i2c;
115 	struct regulator *vdd;
116 	u8 skip_config;
117 	struct gpio_desc *gpio_reset;
118 	u16 vendor_id;
119 	u16 product_id;
120 	u16 device_id;
121 	u8  conf_data1;
122 	u8  conf_data2;
123 	u8  conf_data3;
124 	u8  non_rem_dev;
125 	u8  port_disable_sp;
126 	u8  port_disable_bp;
127 	u8  max_power_sp;
128 	u8  max_power_bp;
129 	u8  max_current_sp;
130 	u8  max_current_bp;
131 	u8  power_on_time;
132 	u16 lang_id;
133 	u8 manufacturer_len;
134 	u8 product_len;
135 	u8 serial_len;
136 	char manufacturer[USB251XB_STRING_BUFSIZE];
137 	char product[USB251XB_STRING_BUFSIZE];
138 	char serial[USB251XB_STRING_BUFSIZE];
139 	u8  bat_charge_en;
140 	u8  boost_up;
141 	u8  boost_57;
142 	u8  boost_14;
143 	u8  port_swap;
144 	u8  port_map12;
145 	u8  port_map34;
146 	u8  port_map56;
147 	u8  port_map7;
148 	u8  status;
149 };
150 
151 struct usb251xb_data {
152 	u16 product_id;
153 	u8 port_cnt;
154 	bool led_support;
155 	bool bat_support;
156 	char product_str[USB251XB_STRING_BUFSIZE / 2]; /* ASCII string */
157 };
158 
159 static const struct usb251xb_data usb2422_data = {
160 	.product_id = 0x2422,
161 	.port_cnt = 2,
162 	.led_support = false,
163 	.bat_support = true,
164 	.product_str = "USB2422",
165 };
166 
167 static const struct usb251xb_data usb2512b_data = {
168 	.product_id = 0x2512,
169 	.port_cnt = 2,
170 	.led_support = false,
171 	.bat_support = true,
172 	.product_str = "USB2512B",
173 };
174 
175 static const struct usb251xb_data usb2512bi_data = {
176 	.product_id = 0x2512,
177 	.port_cnt = 2,
178 	.led_support = false,
179 	.bat_support = true,
180 	.product_str = "USB2512Bi",
181 };
182 
183 static const struct usb251xb_data usb2513b_data = {
184 	.product_id = 0x2513,
185 	.port_cnt = 3,
186 	.led_support = false,
187 	.bat_support = true,
188 	.product_str = "USB2513B",
189 };
190 
191 static const struct usb251xb_data usb2513bi_data = {
192 	.product_id = 0x2513,
193 	.port_cnt = 3,
194 	.led_support = false,
195 	.bat_support = true,
196 	.product_str = "USB2513Bi",
197 };
198 
199 static const struct usb251xb_data usb2514b_data = {
200 	.product_id = 0x2514,
201 	.port_cnt = 4,
202 	.led_support = false,
203 	.bat_support = true,
204 	.product_str = "USB2514B",
205 };
206 
207 static const struct usb251xb_data usb2514bi_data = {
208 	.product_id = 0x2514,
209 	.port_cnt = 4,
210 	.led_support = false,
211 	.bat_support = true,
212 	.product_str = "USB2514Bi",
213 };
214 
215 static const struct usb251xb_data usb2517_data = {
216 	.product_id = 0x2517,
217 	.port_cnt = 7,
218 	.led_support = true,
219 	.bat_support = false,
220 	.product_str = "USB2517",
221 };
222 
223 static const struct usb251xb_data usb2517i_data = {
224 	.product_id = 0x2517,
225 	.port_cnt = 7,
226 	.led_support = true,
227 	.bat_support = false,
228 	.product_str = "USB2517i",
229 };
230 
231 #ifdef CONFIG_GPIOLIB
232 static int usb251xb_check_dev_children(struct device *dev, void *child)
233 {
234 	if (dev->type == &i2c_adapter_type) {
235 		return device_for_each_child(dev, child,
236 					     usb251xb_check_dev_children);
237 	}
238 
239 	return (dev == child);
240 }
241 
242 static int usb251x_check_gpio_chip(struct usb251xb *hub)
243 {
244 	struct gpio_chip *gc = gpiod_to_chip(hub->gpio_reset);
245 	struct i2c_adapter *adap = hub->i2c->adapter;
246 	int ret;
247 
248 	if (!hub->gpio_reset)
249 		return 0;
250 
251 	if (!gc)
252 		return -EINVAL;
253 
254 	ret = usb251xb_check_dev_children(&adap->dev, gc->parent);
255 	if (ret) {
256 		dev_err(hub->dev, "Reset GPIO chip is at the same i2c-bus\n");
257 		return -EINVAL;
258 	}
259 
260 	return 0;
261 }
262 #else
263 static int usb251x_check_gpio_chip(struct usb251xb *hub)
264 {
265 	return 0;
266 }
267 #endif
268 
269 static void usb251xb_reset(struct usb251xb *hub)
270 {
271 	if (!hub->gpio_reset)
272 		return;
273 
274 	i2c_lock_bus(hub->i2c->adapter, I2C_LOCK_SEGMENT);
275 
276 	gpiod_set_value_cansleep(hub->gpio_reset, 1);
277 	usleep_range(1, 10);	/* >=1us RESET_N asserted */
278 	gpiod_set_value_cansleep(hub->gpio_reset, 0);
279 
280 	/* wait for hub recovery/stabilization */
281 	usleep_range(500, 750);	/* >=500us after RESET_N deasserted */
282 
283 	i2c_unlock_bus(hub->i2c->adapter, I2C_LOCK_SEGMENT);
284 }
285 
286 static int usb251xb_connect(struct usb251xb *hub)
287 {
288 	struct device *dev = hub->dev;
289 	int err, i;
290 	char i2c_wb[USB251XB_I2C_REG_SZ];
291 
292 	memset(i2c_wb, 0, USB251XB_I2C_REG_SZ);
293 
294 	if (hub->skip_config) {
295 		dev_info(dev, "Skip hub configuration, only attach.\n");
296 		i2c_wb[0] = 0x01;
297 		i2c_wb[1] = USB251XB_STATUS_COMMAND_ATTACH;
298 
299 		usb251xb_reset(hub);
300 
301 		err = i2c_smbus_write_i2c_block_data(hub->i2c,
302 				USB251XB_ADDR_STATUS_COMMAND, 2, i2c_wb);
303 		if (err) {
304 			dev_err(dev, "attaching hub failed: %d\n", err);
305 			return err;
306 		}
307 		return 0;
308 	}
309 
310 	i2c_wb[USB251XB_ADDR_VENDOR_ID_MSB]     = (hub->vendor_id >> 8) & 0xFF;
311 	i2c_wb[USB251XB_ADDR_VENDOR_ID_LSB]     = hub->vendor_id & 0xFF;
312 	i2c_wb[USB251XB_ADDR_PRODUCT_ID_MSB]    = (hub->product_id >> 8) & 0xFF;
313 	i2c_wb[USB251XB_ADDR_PRODUCT_ID_LSB]    = hub->product_id & 0xFF;
314 	i2c_wb[USB251XB_ADDR_DEVICE_ID_MSB]     = (hub->device_id >> 8) & 0xFF;
315 	i2c_wb[USB251XB_ADDR_DEVICE_ID_LSB]     = hub->device_id & 0xFF;
316 	i2c_wb[USB251XB_ADDR_CONFIG_DATA_1]     = hub->conf_data1;
317 	i2c_wb[USB251XB_ADDR_CONFIG_DATA_2]     = hub->conf_data2;
318 	i2c_wb[USB251XB_ADDR_CONFIG_DATA_3]     = hub->conf_data3;
319 	i2c_wb[USB251XB_ADDR_NON_REMOVABLE_DEVICES] = hub->non_rem_dev;
320 	i2c_wb[USB251XB_ADDR_PORT_DISABLE_SELF] = hub->port_disable_sp;
321 	i2c_wb[USB251XB_ADDR_PORT_DISABLE_BUS]  = hub->port_disable_bp;
322 	i2c_wb[USB251XB_ADDR_MAX_POWER_SELF]    = hub->max_power_sp;
323 	i2c_wb[USB251XB_ADDR_MAX_POWER_BUS]     = hub->max_power_bp;
324 	i2c_wb[USB251XB_ADDR_MAX_CURRENT_SELF]  = hub->max_current_sp;
325 	i2c_wb[USB251XB_ADDR_MAX_CURRENT_BUS]   = hub->max_current_bp;
326 	i2c_wb[USB251XB_ADDR_POWER_ON_TIME]     = hub->power_on_time;
327 	i2c_wb[USB251XB_ADDR_LANGUAGE_ID_HIGH]  = (hub->lang_id >> 8) & 0xFF;
328 	i2c_wb[USB251XB_ADDR_LANGUAGE_ID_LOW]   = hub->lang_id & 0xFF;
329 	i2c_wb[USB251XB_ADDR_MANUFACTURER_STRING_LEN] = hub->manufacturer_len;
330 	i2c_wb[USB251XB_ADDR_PRODUCT_STRING_LEN]      = hub->product_len;
331 	i2c_wb[USB251XB_ADDR_SERIAL_STRING_LEN]       = hub->serial_len;
332 	memcpy(&i2c_wb[USB251XB_ADDR_MANUFACTURER_STRING], hub->manufacturer,
333 	       USB251XB_STRING_BUFSIZE);
334 	memcpy(&i2c_wb[USB251XB_ADDR_SERIAL_STRING], hub->serial,
335 	       USB251XB_STRING_BUFSIZE);
336 	memcpy(&i2c_wb[USB251XB_ADDR_PRODUCT_STRING], hub->product,
337 	       USB251XB_STRING_BUFSIZE);
338 	i2c_wb[USB251XB_ADDR_BATTERY_CHARGING_ENABLE] = hub->bat_charge_en;
339 	i2c_wb[USB251XB_ADDR_BOOST_UP]          = hub->boost_up;
340 	i2c_wb[USB251XB_ADDR_BOOST_57]          = hub->boost_57;
341 	i2c_wb[USB251XB_ADDR_BOOST_14]          = hub->boost_14;
342 	i2c_wb[USB251XB_ADDR_PORT_SWAP]         = hub->port_swap;
343 	i2c_wb[USB251XB_ADDR_PORT_MAP_12]       = hub->port_map12;
344 	i2c_wb[USB251XB_ADDR_PORT_MAP_34]       = hub->port_map34;
345 	i2c_wb[USB251XB_ADDR_PORT_MAP_56]       = hub->port_map56;
346 	i2c_wb[USB251XB_ADDR_PORT_MAP_7]        = hub->port_map7;
347 	i2c_wb[USB251XB_ADDR_STATUS_COMMAND] = USB251XB_STATUS_COMMAND_ATTACH;
348 
349 	usb251xb_reset(hub);
350 
351 	/* write registers */
352 	for (i = 0; i < (USB251XB_I2C_REG_SZ / USB251XB_I2C_WRITE_SZ); i++) {
353 		int offset = i * USB251XB_I2C_WRITE_SZ;
354 		char wbuf[USB251XB_I2C_WRITE_SZ + 1];
355 
356 		/* The first data byte transferred tells the hub how many data
357 		 * bytes will follow (byte count).
358 		 */
359 		wbuf[0] = USB251XB_I2C_WRITE_SZ;
360 		memcpy(&wbuf[1], &i2c_wb[offset], USB251XB_I2C_WRITE_SZ);
361 
362 		dev_dbg(dev, "writing %d byte block %d to 0x%02X\n",
363 			USB251XB_I2C_WRITE_SZ, i, offset);
364 
365 		err = i2c_smbus_write_i2c_block_data(hub->i2c, offset,
366 						     USB251XB_I2C_WRITE_SZ + 1,
367 						     wbuf);
368 		if (err)
369 			goto out_err;
370 	}
371 
372 	dev_info(dev, "Hub configuration was successful.\n");
373 	return 0;
374 
375 out_err:
376 	dev_err(dev, "configuring block %d failed: %d\n", i, err);
377 	return err;
378 }
379 
380 #ifdef CONFIG_OF
381 static void usb251xb_get_ports_field(struct usb251xb *hub,
382 				    const char *prop_name, u8 port_cnt,
383 				    bool ds_only, u8 *fld)
384 {
385 	struct device *dev = hub->dev;
386 	struct property *prop;
387 	const __be32 *p;
388 	u32 port;
389 
390 	of_property_for_each_u32(dev->of_node, prop_name, prop, p, port) {
391 		if ((port >= ds_only ? 1 : 0) && (port <= port_cnt))
392 			*fld |= BIT(port);
393 		else
394 			dev_warn(dev, "port %u doesn't exist\n", port);
395 	}
396 }
397 
398 static int usb251xb_get_ofdata(struct usb251xb *hub,
399 			       const struct usb251xb_data *data)
400 {
401 	struct device *dev = hub->dev;
402 	struct device_node *np = dev->of_node;
403 	int len;
404 	u32 property_u32 = 0;
405 	const char *cproperty_char;
406 	char str[USB251XB_STRING_BUFSIZE / 2];
407 
408 	if (!np) {
409 		dev_err(dev, "failed to get ofdata\n");
410 		return -ENODEV;
411 	}
412 
413 	if (of_get_property(np, "skip-config", NULL))
414 		hub->skip_config = 1;
415 	else
416 		hub->skip_config = 0;
417 
418 	hub->gpio_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
419 	if (IS_ERR(hub->gpio_reset))
420 		return dev_err_probe(dev, PTR_ERR(hub->gpio_reset),
421 				     "unable to request GPIO reset pin\n");
422 
423 	if (of_property_read_u16_array(np, "vendor-id", &hub->vendor_id, 1))
424 		hub->vendor_id = USB251XB_DEF_VENDOR_ID;
425 
426 	if (of_property_read_u16_array(np, "product-id",
427 				       &hub->product_id, 1))
428 		hub->product_id = data->product_id;
429 
430 	if (of_property_read_u16_array(np, "device-id", &hub->device_id, 1))
431 		hub->device_id = USB251XB_DEF_DEVICE_ID;
432 
433 	hub->conf_data1 = USB251XB_DEF_CONFIG_DATA_1;
434 	if (of_get_property(np, "self-powered", NULL)) {
435 		hub->conf_data1 |= BIT(7);
436 
437 		/* Configure Over-Current sens when self-powered */
438 		hub->conf_data1 &= ~BIT(2);
439 		if (of_get_property(np, "ganged-sensing", NULL))
440 			hub->conf_data1 &= ~BIT(1);
441 		else if (of_get_property(np, "individual-sensing", NULL))
442 			hub->conf_data1 |= BIT(1);
443 	} else if (of_get_property(np, "bus-powered", NULL)) {
444 		hub->conf_data1 &= ~BIT(7);
445 
446 		/* Disable Over-Current sense when bus-powered */
447 		hub->conf_data1 |= BIT(2);
448 	}
449 
450 	if (of_get_property(np, "disable-hi-speed", NULL))
451 		hub->conf_data1 |= BIT(5);
452 
453 	if (of_get_property(np, "multi-tt", NULL))
454 		hub->conf_data1 |= BIT(4);
455 	else if (of_get_property(np, "single-tt", NULL))
456 		hub->conf_data1 &= ~BIT(4);
457 
458 	if (of_get_property(np, "disable-eop", NULL))
459 		hub->conf_data1 |= BIT(3);
460 
461 	if (of_get_property(np, "individual-port-switching", NULL))
462 		hub->conf_data1 |= BIT(0);
463 	else if (of_get_property(np, "ganged-port-switching", NULL))
464 		hub->conf_data1 &= ~BIT(0);
465 
466 	hub->conf_data2 = USB251XB_DEF_CONFIG_DATA_2;
467 	if (of_get_property(np, "dynamic-power-switching", NULL))
468 		hub->conf_data2 |= BIT(7);
469 
470 	if (!of_property_read_u32(np, "oc-delay-us", &property_u32)) {
471 		if (property_u32 == 100) {
472 			/* 100 us*/
473 			hub->conf_data2 &= ~BIT(5);
474 			hub->conf_data2 &= ~BIT(4);
475 		} else if (property_u32 == 4000) {
476 			/* 4 ms */
477 			hub->conf_data2 &= ~BIT(5);
478 			hub->conf_data2 |= BIT(4);
479 		} else if (property_u32 == 16000) {
480 			/* 16 ms */
481 			hub->conf_data2 |= BIT(5);
482 			hub->conf_data2 |= BIT(4);
483 		} else {
484 			/* 8 ms (DEFAULT) */
485 			hub->conf_data2 |= BIT(5);
486 			hub->conf_data2 &= ~BIT(4);
487 		}
488 	}
489 
490 	if (of_get_property(np, "compound-device", NULL))
491 		hub->conf_data2 |= BIT(3);
492 
493 	hub->conf_data3 = USB251XB_DEF_CONFIG_DATA_3;
494 	if (of_get_property(np, "port-mapping-mode", NULL))
495 		hub->conf_data3 |= BIT(3);
496 
497 	if (data->led_support && of_get_property(np, "led-usb-mode", NULL))
498 		hub->conf_data3 &= ~BIT(1);
499 
500 	if (of_get_property(np, "string-support", NULL))
501 		hub->conf_data3 |= BIT(0);
502 
503 	hub->non_rem_dev = USB251XB_DEF_NON_REMOVABLE_DEVICES;
504 	usb251xb_get_ports_field(hub, "non-removable-ports", data->port_cnt,
505 				 true, &hub->non_rem_dev);
506 
507 	hub->port_disable_sp = USB251XB_DEF_PORT_DISABLE_SELF;
508 	usb251xb_get_ports_field(hub, "sp-disabled-ports", data->port_cnt,
509 				 true, &hub->port_disable_sp);
510 
511 	hub->port_disable_bp = USB251XB_DEF_PORT_DISABLE_BUS;
512 	usb251xb_get_ports_field(hub, "bp-disabled-ports", data->port_cnt,
513 				 true, &hub->port_disable_bp);
514 
515 	hub->max_power_sp = USB251XB_DEF_MAX_POWER_SELF;
516 	if (!of_property_read_u32(np, "sp-max-total-current-microamp",
517 	    &property_u32))
518 		hub->max_power_sp = min_t(u8, property_u32 / 2000, 50);
519 
520 	hub->max_power_bp = USB251XB_DEF_MAX_POWER_BUS;
521 	if (!of_property_read_u32(np, "bp-max-total-current-microamp",
522 	    &property_u32))
523 		hub->max_power_bp = min_t(u8, property_u32 / 2000, 255);
524 
525 	hub->max_current_sp = USB251XB_DEF_MAX_CURRENT_SELF;
526 	if (!of_property_read_u32(np, "sp-max-removable-current-microamp",
527 	    &property_u32))
528 		hub->max_current_sp = min_t(u8, property_u32 / 2000, 50);
529 
530 	hub->max_current_bp = USB251XB_DEF_MAX_CURRENT_BUS;
531 	if (!of_property_read_u32(np, "bp-max-removable-current-microamp",
532 	    &property_u32))
533 		hub->max_current_bp = min_t(u8, property_u32 / 2000, 255);
534 
535 	hub->power_on_time = USB251XB_DEF_POWER_ON_TIME;
536 	if (!of_property_read_u32(np, "power-on-time-ms", &property_u32))
537 		hub->power_on_time = min_t(u8, property_u32 / 2, 255);
538 
539 	if (of_property_read_u16_array(np, "language-id", &hub->lang_id, 1))
540 		hub->lang_id = USB251XB_DEF_LANGUAGE_ID;
541 
542 	if (of_property_read_u8(np, "boost-up", &hub->boost_up))
543 		hub->boost_up = USB251XB_DEF_BOOST_UP;
544 
545 	cproperty_char = of_get_property(np, "manufacturer", NULL);
546 	strscpy(str, cproperty_char ? : USB251XB_DEF_MANUFACTURER_STRING,
547 		sizeof(str));
548 	hub->manufacturer_len = strlen(str) & 0xFF;
549 	memset(hub->manufacturer, 0, USB251XB_STRING_BUFSIZE);
550 	len = min_t(size_t, USB251XB_STRING_BUFSIZE / 2, strlen(str));
551 	len = utf8s_to_utf16s(str, len, UTF16_LITTLE_ENDIAN,
552 			      (wchar_t *)hub->manufacturer,
553 			      USB251XB_STRING_BUFSIZE);
554 
555 	cproperty_char = of_get_property(np, "product", NULL);
556 	strscpy(str, cproperty_char ? : data->product_str, sizeof(str));
557 	hub->product_len = strlen(str) & 0xFF;
558 	memset(hub->product, 0, USB251XB_STRING_BUFSIZE);
559 	len = min_t(size_t, USB251XB_STRING_BUFSIZE / 2, strlen(str));
560 	len = utf8s_to_utf16s(str, len, UTF16_LITTLE_ENDIAN,
561 			      (wchar_t *)hub->product,
562 			      USB251XB_STRING_BUFSIZE);
563 
564 	cproperty_char = of_get_property(np, "serial", NULL);
565 	strscpy(str, cproperty_char ? : USB251XB_DEF_SERIAL_STRING,
566 		sizeof(str));
567 	hub->serial_len = strlen(str) & 0xFF;
568 	memset(hub->serial, 0, USB251XB_STRING_BUFSIZE);
569 	len = min_t(size_t, USB251XB_STRING_BUFSIZE / 2, strlen(str));
570 	len = utf8s_to_utf16s(str, len, UTF16_LITTLE_ENDIAN,
571 			      (wchar_t *)hub->serial,
572 			      USB251XB_STRING_BUFSIZE);
573 
574 	/*
575 	 * The datasheet documents the register as 'Port Swap' but in real the
576 	 * register controls the USB DP/DM signal swapping for each port.
577 	 */
578 	hub->port_swap = USB251XB_DEF_PORT_SWAP;
579 	usb251xb_get_ports_field(hub, "swap-dx-lanes", data->port_cnt,
580 				 false, &hub->port_swap);
581 
582 	/* The following parameters are currently not exposed to devicetree, but
583 	 * may be as soon as needed.
584 	 */
585 	hub->bat_charge_en = USB251XB_DEF_BATTERY_CHARGING_ENABLE;
586 	hub->boost_57 = USB251XB_DEF_BOOST_57;
587 	hub->boost_14 = USB251XB_DEF_BOOST_14;
588 	hub->port_map12 = USB251XB_DEF_PORT_MAP_12;
589 	hub->port_map34 = USB251XB_DEF_PORT_MAP_34;
590 	hub->port_map56 = USB251XB_DEF_PORT_MAP_56;
591 	hub->port_map7  = USB251XB_DEF_PORT_MAP_7;
592 
593 	return 0;
594 }
595 
596 static const struct of_device_id usb251xb_of_match[] = {
597 	{
598 		.compatible = "microchip,usb2422",
599 		.data = &usb2422_data,
600 	}, {
601 		.compatible = "microchip,usb2512b",
602 		.data = &usb2512b_data,
603 	}, {
604 		.compatible = "microchip,usb2512bi",
605 		.data = &usb2512bi_data,
606 	}, {
607 		.compatible = "microchip,usb2513b",
608 		.data = &usb2513b_data,
609 	}, {
610 		.compatible = "microchip,usb2513bi",
611 		.data = &usb2513bi_data,
612 	}, {
613 		.compatible = "microchip,usb2514b",
614 		.data = &usb2514b_data,
615 	}, {
616 		.compatible = "microchip,usb2514bi",
617 		.data = &usb2514bi_data,
618 	}, {
619 		.compatible = "microchip,usb2517",
620 		.data = &usb2517_data,
621 	}, {
622 		.compatible = "microchip,usb2517i",
623 		.data = &usb2517i_data,
624 	}, {
625 		/* sentinel */
626 	}
627 };
628 MODULE_DEVICE_TABLE(of, usb251xb_of_match);
629 #else /* CONFIG_OF */
630 static int usb251xb_get_ofdata(struct usb251xb *hub,
631 			       const struct usb251xb_data *data)
632 {
633 	return 0;
634 }
635 #endif /* CONFIG_OF */
636 
637 static void usb251xb_regulator_disable_action(void *data)
638 {
639 	struct usb251xb *hub = data;
640 
641 	regulator_disable(hub->vdd);
642 }
643 
644 static int usb251xb_probe(struct usb251xb *hub)
645 {
646 	struct device *dev = hub->dev;
647 	struct device_node *np = dev->of_node;
648 	const struct usb251xb_data *usb_data = of_device_get_match_data(dev);
649 	int err;
650 
651 	if (np && usb_data) {
652 		err = usb251xb_get_ofdata(hub, usb_data);
653 		if (err) {
654 			dev_err(dev, "failed to get ofdata: %d\n", err);
655 			return err;
656 		}
657 	}
658 
659 	/*
660 	 * usb251x SMBus-slave SCL lane is muxed with CFG_SEL0 pin. So if anyone
661 	 * tries to work with the bus at the moment the hub reset is released,
662 	 * it may cause an invalid config being latched by usb251x. Particularly
663 	 * one of the config modes makes the hub loading a default registers
664 	 * value without SMBus-slave interface activation. If the hub
665 	 * accidentally gets this mode, this will cause the driver SMBus-
666 	 * functions failure. Normally we could just lock the SMBus-segment the
667 	 * hub i2c-interface resides for the device-specific reset timing. But
668 	 * the GPIO controller, which is used to handle the hub reset, might be
669 	 * placed at the same i2c-bus segment. In this case an error should be
670 	 * returned since we can't safely use the GPIO controller to clear the
671 	 * reset state (it may affect the hub configuration) and we can't lock
672 	 * the i2c-bus segment (it will cause a deadlock).
673 	 */
674 	err = usb251x_check_gpio_chip(hub);
675 	if (err)
676 		return err;
677 
678 	hub->vdd = devm_regulator_get(dev, "vdd");
679 	if (IS_ERR(hub->vdd))
680 		return PTR_ERR(hub->vdd);
681 
682 	err = regulator_enable(hub->vdd);
683 	if (err)
684 		return err;
685 
686 	err = devm_add_action_or_reset(dev,
687 				       usb251xb_regulator_disable_action, hub);
688 	if (err)
689 		return err;
690 
691 	err = usb251xb_connect(hub);
692 	if (err) {
693 		dev_err(dev, "Failed to connect hub (%d)\n", err);
694 		return err;
695 	}
696 
697 	dev_info(dev, "Hub probed successfully\n");
698 
699 	return 0;
700 }
701 
702 static int usb251xb_i2c_probe(struct i2c_client *i2c)
703 {
704 	struct usb251xb *hub;
705 
706 	hub = devm_kzalloc(&i2c->dev, sizeof(struct usb251xb), GFP_KERNEL);
707 	if (!hub)
708 		return -ENOMEM;
709 
710 	i2c_set_clientdata(i2c, hub);
711 	hub->dev = &i2c->dev;
712 	hub->i2c = i2c;
713 
714 	return usb251xb_probe(hub);
715 }
716 
717 static int __maybe_unused usb251xb_suspend(struct device *dev)
718 {
719 	struct i2c_client *client = to_i2c_client(dev);
720 	struct usb251xb *hub = i2c_get_clientdata(client);
721 
722 	return regulator_disable(hub->vdd);
723 }
724 
725 static int __maybe_unused usb251xb_resume(struct device *dev)
726 {
727 	struct i2c_client *client = to_i2c_client(dev);
728 	struct usb251xb *hub = i2c_get_clientdata(client);
729 	int err;
730 
731 	err = regulator_enable(hub->vdd);
732 	if (err)
733 		return err;
734 
735 	return usb251xb_connect(hub);
736 }
737 
738 static SIMPLE_DEV_PM_OPS(usb251xb_pm_ops, usb251xb_suspend, usb251xb_resume);
739 
740 static const struct i2c_device_id usb251xb_id[] = {
741 	{ "usb2422", 0 },
742 	{ "usb2512b", 0 },
743 	{ "usb2512bi", 0 },
744 	{ "usb2513b", 0 },
745 	{ "usb2513bi", 0 },
746 	{ "usb2514b", 0 },
747 	{ "usb2514bi", 0 },
748 	{ "usb2517", 0 },
749 	{ "usb2517i", 0 },
750 	{ /* sentinel */ }
751 };
752 MODULE_DEVICE_TABLE(i2c, usb251xb_id);
753 
754 static struct i2c_driver usb251xb_i2c_driver = {
755 	.driver = {
756 		.name = DRIVER_NAME,
757 		.of_match_table = of_match_ptr(usb251xb_of_match),
758 		.pm = &usb251xb_pm_ops,
759 	},
760 	.probe_new = usb251xb_i2c_probe,
761 	.id_table = usb251xb_id,
762 };
763 
764 module_i2c_driver(usb251xb_i2c_driver);
765 
766 MODULE_AUTHOR("Richard Leitner <richard.leitner@skidata.com>");
767 MODULE_DESCRIPTION("USB251x/xBi USB 2.0 Hub Controller Driver");
768 MODULE_LICENSE("GPL");
769