xref: /openbmc/linux/drivers/usb/misc/usb251xb.c (revision b830f94f)
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/slab.h>
21 
22 /* Internal Register Set Addresses & Default Values acc. to DS00001692C */
23 #define USB251XB_ADDR_VENDOR_ID_LSB	0x00
24 #define USB251XB_ADDR_VENDOR_ID_MSB	0x01
25 #define USB251XB_DEF_VENDOR_ID		0x0424
26 
27 #define USB251XB_ADDR_PRODUCT_ID_LSB	0x02
28 #define USB251XB_ADDR_PRODUCT_ID_MSB	0x03
29 #define USB251XB_DEF_PRODUCT_ID_12	0x2512 /* USB2512B/12Bi */
30 #define USB251XB_DEF_PRODUCT_ID_13	0x2513 /* USB2513B/13Bi */
31 #define USB251XB_DEF_PRODUCT_ID_14	0x2514 /* USB2514B/14Bi */
32 #define USB251XB_DEF_PRODUCT_ID_17	0x2517 /* USB2517/17i */
33 
34 #define USB251XB_ADDR_DEVICE_ID_LSB	0x04
35 #define USB251XB_ADDR_DEVICE_ID_MSB	0x05
36 #define USB251XB_DEF_DEVICE_ID		0x0BB3
37 
38 #define USB251XB_ADDR_CONFIG_DATA_1	0x06
39 #define USB251XB_DEF_CONFIG_DATA_1	0x9B
40 #define USB251XB_ADDR_CONFIG_DATA_2	0x07
41 #define USB251XB_DEF_CONFIG_DATA_2	0x20
42 #define USB251XB_ADDR_CONFIG_DATA_3	0x08
43 #define USB251XB_DEF_CONFIG_DATA_3	0x02
44 
45 #define USB251XB_ADDR_NON_REMOVABLE_DEVICES	0x09
46 #define USB251XB_DEF_NON_REMOVABLE_DEVICES	0x00
47 
48 #define USB251XB_ADDR_PORT_DISABLE_SELF	0x0A
49 #define USB251XB_DEF_PORT_DISABLE_SELF	0x00
50 #define USB251XB_ADDR_PORT_DISABLE_BUS	0x0B
51 #define USB251XB_DEF_PORT_DISABLE_BUS	0x00
52 
53 #define USB251XB_ADDR_MAX_POWER_SELF	0x0C
54 #define USB251XB_DEF_MAX_POWER_SELF	0x01
55 #define USB251XB_ADDR_MAX_POWER_BUS	0x0D
56 #define USB251XB_DEF_MAX_POWER_BUS	0x32
57 
58 #define USB251XB_ADDR_MAX_CURRENT_SELF	0x0E
59 #define USB251XB_DEF_MAX_CURRENT_SELF	0x01
60 #define USB251XB_ADDR_MAX_CURRENT_BUS	0x0F
61 #define USB251XB_DEF_MAX_CURRENT_BUS	0x32
62 
63 #define USB251XB_ADDR_POWER_ON_TIME	0x10
64 #define USB251XB_DEF_POWER_ON_TIME	0x32
65 
66 #define USB251XB_ADDR_LANGUAGE_ID_HIGH	0x11
67 #define USB251XB_ADDR_LANGUAGE_ID_LOW	0x12
68 #define USB251XB_DEF_LANGUAGE_ID	0x0000
69 
70 #define USB251XB_STRING_BUFSIZE			62
71 #define USB251XB_ADDR_MANUFACTURER_STRING_LEN	0x13
72 #define USB251XB_ADDR_MANUFACTURER_STRING	0x16
73 #define USB251XB_DEF_MANUFACTURER_STRING	"Microchip"
74 
75 #define USB251XB_ADDR_PRODUCT_STRING_LEN	0x14
76 #define USB251XB_ADDR_PRODUCT_STRING		0x54
77 #define USB251XB_DEF_PRODUCT_STRING		"USB251xB/xBi/7i"
78 
79 #define USB251XB_ADDR_SERIAL_STRING_LEN		0x15
80 #define USB251XB_ADDR_SERIAL_STRING		0x92
81 #define USB251XB_DEF_SERIAL_STRING		""
82 
83 #define USB251XB_ADDR_BATTERY_CHARGING_ENABLE	0xD0
84 #define USB251XB_DEF_BATTERY_CHARGING_ENABLE	0x00
85 
86 #define USB251XB_ADDR_BOOST_UP	0xF6
87 #define USB251XB_DEF_BOOST_UP	0x00
88 #define USB251XB_ADDR_BOOST_57	0xF7
89 #define USB251XB_DEF_BOOST_57	0x00
90 #define USB251XB_ADDR_BOOST_14	0xF8
91 #define USB251XB_DEF_BOOST_14	0x00
92 
93 #define USB251XB_ADDR_PORT_SWAP	0xFA
94 #define USB251XB_DEF_PORT_SWAP	0x00
95 
96 #define USB251XB_ADDR_PORT_MAP_12	0xFB
97 #define USB251XB_DEF_PORT_MAP_12	0x00
98 #define USB251XB_ADDR_PORT_MAP_34	0xFC
99 #define USB251XB_DEF_PORT_MAP_34	0x00 /* USB251{3B/i,4B/i,7/i} only */
100 #define USB251XB_ADDR_PORT_MAP_56	0xFD
101 #define USB251XB_DEF_PORT_MAP_56	0x00 /* USB2517/i only */
102 #define USB251XB_ADDR_PORT_MAP_7	0xFE
103 #define USB251XB_DEF_PORT_MAP_7		0x00 /* USB2517/i only */
104 
105 #define USB251XB_ADDR_STATUS_COMMAND		0xFF
106 #define USB251XB_STATUS_COMMAND_SMBUS_DOWN	0x04
107 #define USB251XB_STATUS_COMMAND_RESET		0x02
108 #define USB251XB_STATUS_COMMAND_ATTACH		0x01
109 
110 #define USB251XB_I2C_REG_SZ	0x100
111 #define USB251XB_I2C_WRITE_SZ	0x10
112 
113 #define DRIVER_NAME	"usb251xb"
114 #define DRIVER_DESC	"Microchip USB 2.0 Hi-Speed Hub Controller"
115 
116 struct usb251xb {
117 	struct device *dev;
118 	struct i2c_client *i2c;
119 	u8 skip_config;
120 	struct gpio_desc *gpio_reset;
121 	u16 vendor_id;
122 	u16 product_id;
123 	u16 device_id;
124 	u8  conf_data1;
125 	u8  conf_data2;
126 	u8  conf_data3;
127 	u8  non_rem_dev;
128 	u8  port_disable_sp;
129 	u8  port_disable_bp;
130 	u8  max_power_sp;
131 	u8  max_power_bp;
132 	u8  max_current_sp;
133 	u8  max_current_bp;
134 	u8  power_on_time;
135 	u16 lang_id;
136 	u8 manufacturer_len;
137 	u8 product_len;
138 	u8 serial_len;
139 	char manufacturer[USB251XB_STRING_BUFSIZE];
140 	char product[USB251XB_STRING_BUFSIZE];
141 	char serial[USB251XB_STRING_BUFSIZE];
142 	u8  bat_charge_en;
143 	u8  boost_up;
144 	u8  boost_57;
145 	u8  boost_14;
146 	u8  port_swap;
147 	u8  port_map12;
148 	u8  port_map34;
149 	u8  port_map56;
150 	u8  port_map7;
151 	u8  status;
152 };
153 
154 struct usb251xb_data {
155 	u16 product_id;
156 	u8 port_cnt;
157 	bool led_support;
158 	bool bat_support;
159 	char product_str[USB251XB_STRING_BUFSIZE / 2]; /* ASCII string */
160 };
161 
162 static const struct usb251xb_data usb2512b_data = {
163 	.product_id = 0x2512,
164 	.port_cnt = 2,
165 	.led_support = false,
166 	.bat_support = true,
167 	.product_str = "USB2512B",
168 };
169 
170 static const struct usb251xb_data usb2512bi_data = {
171 	.product_id = 0x2512,
172 	.port_cnt = 2,
173 	.led_support = false,
174 	.bat_support = true,
175 	.product_str = "USB2512Bi",
176 };
177 
178 static const struct usb251xb_data usb2513b_data = {
179 	.product_id = 0x2513,
180 	.port_cnt = 3,
181 	.led_support = false,
182 	.bat_support = true,
183 	.product_str = "USB2513B",
184 };
185 
186 static const struct usb251xb_data usb2513bi_data = {
187 	.product_id = 0x2513,
188 	.port_cnt = 3,
189 	.led_support = false,
190 	.bat_support = true,
191 	.product_str = "USB2513Bi",
192 };
193 
194 static const struct usb251xb_data usb2514b_data = {
195 	.product_id = 0x2514,
196 	.port_cnt = 4,
197 	.led_support = false,
198 	.bat_support = true,
199 	.product_str = "USB2514B",
200 };
201 
202 static const struct usb251xb_data usb2514bi_data = {
203 	.product_id = 0x2514,
204 	.port_cnt = 4,
205 	.led_support = false,
206 	.bat_support = true,
207 	.product_str = "USB2514Bi",
208 };
209 
210 static const struct usb251xb_data usb2517_data = {
211 	.product_id = 0x2517,
212 	.port_cnt = 7,
213 	.led_support = true,
214 	.bat_support = false,
215 	.product_str = "USB2517",
216 };
217 
218 static const struct usb251xb_data usb2517i_data = {
219 	.product_id = 0x2517,
220 	.port_cnt = 7,
221 	.led_support = true,
222 	.bat_support = false,
223 	.product_str = "USB2517i",
224 };
225 
226 #ifdef CONFIG_GPIOLIB
227 static int usb251xb_check_dev_children(struct device *dev, void *child)
228 {
229 	if (dev->type == &i2c_adapter_type) {
230 		return device_for_each_child(dev, child,
231 					     usb251xb_check_dev_children);
232 	}
233 
234 	return (dev == child);
235 }
236 
237 static int usb251x_check_gpio_chip(struct usb251xb *hub)
238 {
239 	struct gpio_chip *gc = gpiod_to_chip(hub->gpio_reset);
240 	struct i2c_adapter *adap = hub->i2c->adapter;
241 	int ret;
242 
243 	if (!hub->gpio_reset)
244 		return 0;
245 
246 	if (!gc)
247 		return -EINVAL;
248 
249 	ret = usb251xb_check_dev_children(&adap->dev, gc->parent);
250 	if (ret) {
251 		dev_err(hub->dev, "Reset GPIO chip is at the same i2c-bus\n");
252 		return -EINVAL;
253 	}
254 
255 	return 0;
256 }
257 #else
258 static int usb251x_check_gpio_chip(struct usb251xb *hub)
259 {
260 	return 0;
261 }
262 #endif
263 
264 static void usb251xb_reset(struct usb251xb *hub, int state)
265 {
266 	if (!hub->gpio_reset)
267 		return;
268 
269 	i2c_lock_bus(hub->i2c->adapter, I2C_LOCK_SEGMENT);
270 
271 	gpiod_set_value_cansleep(hub->gpio_reset, state);
272 
273 	/* wait for hub recovery/stabilization */
274 	if (!state)
275 		usleep_range(500, 750);	/* >=500us at power on */
276 	else
277 		usleep_range(1, 10);	/* >=1us at power down */
278 
279 	i2c_unlock_bus(hub->i2c->adapter, I2C_LOCK_SEGMENT);
280 }
281 
282 static int usb251xb_connect(struct usb251xb *hub)
283 {
284 	struct device *dev = hub->dev;
285 	int err, i;
286 	char i2c_wb[USB251XB_I2C_REG_SZ];
287 
288 	memset(i2c_wb, 0, USB251XB_I2C_REG_SZ);
289 
290 	if (hub->skip_config) {
291 		dev_info(dev, "Skip hub configuration, only attach.\n");
292 		i2c_wb[0] = 0x01;
293 		i2c_wb[1] = USB251XB_STATUS_COMMAND_ATTACH;
294 
295 		usb251xb_reset(hub, 0);
296 
297 		err = i2c_smbus_write_i2c_block_data(hub->i2c,
298 				USB251XB_ADDR_STATUS_COMMAND, 2, i2c_wb);
299 		if (err) {
300 			dev_err(dev, "attaching hub failed: %d\n", err);
301 			return err;
302 		}
303 		return 0;
304 	}
305 
306 	i2c_wb[USB251XB_ADDR_VENDOR_ID_MSB]     = (hub->vendor_id >> 8) & 0xFF;
307 	i2c_wb[USB251XB_ADDR_VENDOR_ID_LSB]     = hub->vendor_id & 0xFF;
308 	i2c_wb[USB251XB_ADDR_PRODUCT_ID_MSB]    = (hub->product_id >> 8) & 0xFF;
309 	i2c_wb[USB251XB_ADDR_PRODUCT_ID_LSB]    = hub->product_id & 0xFF;
310 	i2c_wb[USB251XB_ADDR_DEVICE_ID_MSB]     = (hub->device_id >> 8) & 0xFF;
311 	i2c_wb[USB251XB_ADDR_DEVICE_ID_LSB]     = hub->device_id & 0xFF;
312 	i2c_wb[USB251XB_ADDR_CONFIG_DATA_1]     = hub->conf_data1;
313 	i2c_wb[USB251XB_ADDR_CONFIG_DATA_2]     = hub->conf_data2;
314 	i2c_wb[USB251XB_ADDR_CONFIG_DATA_3]     = hub->conf_data3;
315 	i2c_wb[USB251XB_ADDR_NON_REMOVABLE_DEVICES] = hub->non_rem_dev;
316 	i2c_wb[USB251XB_ADDR_PORT_DISABLE_SELF] = hub->port_disable_sp;
317 	i2c_wb[USB251XB_ADDR_PORT_DISABLE_BUS]  = hub->port_disable_bp;
318 	i2c_wb[USB251XB_ADDR_MAX_POWER_SELF]    = hub->max_power_sp;
319 	i2c_wb[USB251XB_ADDR_MAX_POWER_BUS]     = hub->max_power_bp;
320 	i2c_wb[USB251XB_ADDR_MAX_CURRENT_SELF]  = hub->max_current_sp;
321 	i2c_wb[USB251XB_ADDR_MAX_CURRENT_BUS]   = hub->max_current_bp;
322 	i2c_wb[USB251XB_ADDR_POWER_ON_TIME]     = hub->power_on_time;
323 	i2c_wb[USB251XB_ADDR_LANGUAGE_ID_HIGH]  = (hub->lang_id >> 8) & 0xFF;
324 	i2c_wb[USB251XB_ADDR_LANGUAGE_ID_LOW]   = hub->lang_id & 0xFF;
325 	i2c_wb[USB251XB_ADDR_MANUFACTURER_STRING_LEN] = hub->manufacturer_len;
326 	i2c_wb[USB251XB_ADDR_PRODUCT_STRING_LEN]      = hub->product_len;
327 	i2c_wb[USB251XB_ADDR_SERIAL_STRING_LEN]       = hub->serial_len;
328 	memcpy(&i2c_wb[USB251XB_ADDR_MANUFACTURER_STRING], hub->manufacturer,
329 	       USB251XB_STRING_BUFSIZE);
330 	memcpy(&i2c_wb[USB251XB_ADDR_SERIAL_STRING], hub->serial,
331 	       USB251XB_STRING_BUFSIZE);
332 	memcpy(&i2c_wb[USB251XB_ADDR_PRODUCT_STRING], hub->product,
333 	       USB251XB_STRING_BUFSIZE);
334 	i2c_wb[USB251XB_ADDR_BATTERY_CHARGING_ENABLE] = hub->bat_charge_en;
335 	i2c_wb[USB251XB_ADDR_BOOST_UP]          = hub->boost_up;
336 	i2c_wb[USB251XB_ADDR_BOOST_57]          = hub->boost_57;
337 	i2c_wb[USB251XB_ADDR_BOOST_14]          = hub->boost_14;
338 	i2c_wb[USB251XB_ADDR_PORT_SWAP]         = hub->port_swap;
339 	i2c_wb[USB251XB_ADDR_PORT_MAP_12]       = hub->port_map12;
340 	i2c_wb[USB251XB_ADDR_PORT_MAP_34]       = hub->port_map34;
341 	i2c_wb[USB251XB_ADDR_PORT_MAP_56]       = hub->port_map56;
342 	i2c_wb[USB251XB_ADDR_PORT_MAP_7]        = hub->port_map7;
343 	i2c_wb[USB251XB_ADDR_STATUS_COMMAND] = USB251XB_STATUS_COMMAND_ATTACH;
344 
345 	usb251xb_reset(hub, 0);
346 
347 	/* write registers */
348 	for (i = 0; i < (USB251XB_I2C_REG_SZ / USB251XB_I2C_WRITE_SZ); i++) {
349 		int offset = i * USB251XB_I2C_WRITE_SZ;
350 		char wbuf[USB251XB_I2C_WRITE_SZ + 1];
351 
352 		/* The first data byte transferred tells the hub how many data
353 		 * bytes will follow (byte count).
354 		 */
355 		wbuf[0] = USB251XB_I2C_WRITE_SZ;
356 		memcpy(&wbuf[1], &i2c_wb[offset], USB251XB_I2C_WRITE_SZ);
357 
358 		dev_dbg(dev, "writing %d byte block %d to 0x%02X\n",
359 			USB251XB_I2C_WRITE_SZ, i, offset);
360 
361 		err = i2c_smbus_write_i2c_block_data(hub->i2c, offset,
362 						     USB251XB_I2C_WRITE_SZ + 1,
363 						     wbuf);
364 		if (err)
365 			goto out_err;
366 	}
367 
368 	dev_info(dev, "Hub configuration was successful.\n");
369 	return 0;
370 
371 out_err:
372 	dev_err(dev, "configuring block %d failed: %d\n", i, err);
373 	return err;
374 }
375 
376 #ifdef CONFIG_OF
377 static void usb251xb_get_ports_field(struct usb251xb *hub,
378 				    const char *prop_name, u8 port_cnt, u8 *fld)
379 {
380 	struct device *dev = hub->dev;
381 	struct property *prop;
382 	const __be32 *p;
383 	u32 port;
384 
385 	of_property_for_each_u32(dev->of_node, prop_name, prop, p, port) {
386 		if ((port >= 1) && (port <= port_cnt))
387 			*fld |= BIT(port);
388 		else
389 			dev_warn(dev, "port %u doesn't exist\n", port);
390 	}
391 }
392 
393 static int usb251xb_get_ofdata(struct usb251xb *hub,
394 			       struct usb251xb_data *data)
395 {
396 	struct device *dev = hub->dev;
397 	struct device_node *np = dev->of_node;
398 	int len, err;
399 	u32 property_u32 = 0;
400 	const char *cproperty_char;
401 	char str[USB251XB_STRING_BUFSIZE / 2];
402 
403 	if (!np) {
404 		dev_err(dev, "failed to get ofdata\n");
405 		return -ENODEV;
406 	}
407 
408 	if (of_get_property(np, "skip-config", NULL))
409 		hub->skip_config = 1;
410 	else
411 		hub->skip_config = 0;
412 
413 	hub->gpio_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
414 	if (PTR_ERR(hub->gpio_reset) == -EPROBE_DEFER) {
415 		return -EPROBE_DEFER;
416 	} else if (IS_ERR(hub->gpio_reset)) {
417 		err = PTR_ERR(hub->gpio_reset);
418 		dev_err(dev, "unable to request GPIO reset pin (%d)\n", err);
419 		return err;
420 	}
421 
422 	if (of_property_read_u16_array(np, "vendor-id", &hub->vendor_id, 1))
423 		hub->vendor_id = USB251XB_DEF_VENDOR_ID;
424 
425 	if (of_property_read_u16_array(np, "product-id",
426 				       &hub->product_id, 1))
427 		hub->product_id = data->product_id;
428 
429 	if (of_property_read_u16_array(np, "device-id", &hub->device_id, 1))
430 		hub->device_id = USB251XB_DEF_DEVICE_ID;
431 
432 	hub->conf_data1 = USB251XB_DEF_CONFIG_DATA_1;
433 	if (of_get_property(np, "self-powered", NULL)) {
434 		hub->conf_data1 |= BIT(7);
435 
436 		/* Configure Over-Current sens when self-powered */
437 		hub->conf_data1 &= ~BIT(2);
438 		if (of_get_property(np, "ganged-sensing", NULL))
439 			hub->conf_data1 &= ~BIT(1);
440 		else if (of_get_property(np, "individual-sensing", NULL))
441 			hub->conf_data1 |= BIT(1);
442 	} else if (of_get_property(np, "bus-powered", NULL)) {
443 		hub->conf_data1 &= ~BIT(7);
444 
445 		/* Disable Over-Current sense when bus-powered */
446 		hub->conf_data1 |= BIT(2);
447 	}
448 
449 	if (of_get_property(np, "disable-hi-speed", NULL))
450 		hub->conf_data1 |= BIT(5);
451 
452 	if (of_get_property(np, "multi-tt", NULL))
453 		hub->conf_data1 |= BIT(4);
454 	else if (of_get_property(np, "single-tt", NULL))
455 		hub->conf_data1 &= ~BIT(4);
456 
457 	if (of_get_property(np, "disable-eop", NULL))
458 		hub->conf_data1 |= BIT(3);
459 
460 	if (of_get_property(np, "individual-port-switching", NULL))
461 		hub->conf_data1 |= BIT(0);
462 	else if (of_get_property(np, "ganged-port-switching", NULL))
463 		hub->conf_data1 &= ~BIT(0);
464 
465 	hub->conf_data2 = USB251XB_DEF_CONFIG_DATA_2;
466 	if (of_get_property(np, "dynamic-power-switching", NULL))
467 		hub->conf_data2 |= BIT(7);
468 
469 	if (!of_property_read_u32(np, "oc-delay-us", &property_u32)) {
470 		if (property_u32 == 100) {
471 			/* 100 us*/
472 			hub->conf_data2 &= ~BIT(5);
473 			hub->conf_data2 &= ~BIT(4);
474 		} else if (property_u32 == 4000) {
475 			/* 4 ms */
476 			hub->conf_data2 &= ~BIT(5);
477 			hub->conf_data2 |= BIT(4);
478 		} else if (property_u32 == 16000) {
479 			/* 16 ms */
480 			hub->conf_data2 |= BIT(5);
481 			hub->conf_data2 |= BIT(4);
482 		} else {
483 			/* 8 ms (DEFAULT) */
484 			hub->conf_data2 |= BIT(5);
485 			hub->conf_data2 &= ~BIT(4);
486 		}
487 	}
488 
489 	if (of_get_property(np, "compound-device", NULL))
490 		hub->conf_data2 |= BIT(3);
491 
492 	hub->conf_data3 = USB251XB_DEF_CONFIG_DATA_3;
493 	if (of_get_property(np, "port-mapping-mode", NULL))
494 		hub->conf_data3 |= BIT(3);
495 
496 	if (data->led_support && of_get_property(np, "led-usb-mode", NULL))
497 		hub->conf_data3 &= ~BIT(1);
498 
499 	if (of_get_property(np, "string-support", NULL))
500 		hub->conf_data3 |= BIT(0);
501 
502 	hub->non_rem_dev = USB251XB_DEF_NON_REMOVABLE_DEVICES;
503 	usb251xb_get_ports_field(hub, "non-removable-ports", data->port_cnt,
504 				 &hub->non_rem_dev);
505 
506 	hub->port_disable_sp = USB251XB_DEF_PORT_DISABLE_SELF;
507 	usb251xb_get_ports_field(hub, "sp-disabled-ports", data->port_cnt,
508 				 &hub->port_disable_sp);
509 
510 	hub->port_disable_bp = USB251XB_DEF_PORT_DISABLE_BUS;
511 	usb251xb_get_ports_field(hub, "bp-disabled-ports", data->port_cnt,
512 				 &hub->port_disable_bp);
513 
514 	hub->max_power_sp = USB251XB_DEF_MAX_POWER_SELF;
515 	if (!of_property_read_u32(np, "sp-max-total-current-microamp",
516 	    &property_u32))
517 		hub->max_power_sp = min_t(u8, property_u32 / 2000, 50);
518 
519 	hub->max_power_bp = USB251XB_DEF_MAX_POWER_BUS;
520 	if (!of_property_read_u32(np, "bp-max-total-current-microamp",
521 	    &property_u32))
522 		hub->max_power_bp = min_t(u8, property_u32 / 2000, 255);
523 
524 	hub->max_current_sp = USB251XB_DEF_MAX_CURRENT_SELF;
525 	if (!of_property_read_u32(np, "sp-max-removable-current-microamp",
526 	    &property_u32))
527 		hub->max_current_sp = min_t(u8, property_u32 / 2000, 50);
528 
529 	hub->max_current_bp = USB251XB_DEF_MAX_CURRENT_BUS;
530 	if (!of_property_read_u32(np, "bp-max-removable-current-microamp",
531 	    &property_u32))
532 		hub->max_current_bp = min_t(u8, property_u32 / 2000, 255);
533 
534 	hub->power_on_time = USB251XB_DEF_POWER_ON_TIME;
535 	if (!of_property_read_u32(np, "power-on-time-ms", &property_u32))
536 		hub->power_on_time = min_t(u8, property_u32 / 2, 255);
537 
538 	if (of_property_read_u16_array(np, "language-id", &hub->lang_id, 1))
539 		hub->lang_id = USB251XB_DEF_LANGUAGE_ID;
540 
541 	cproperty_char = of_get_property(np, "manufacturer", NULL);
542 	strlcpy(str, cproperty_char ? : USB251XB_DEF_MANUFACTURER_STRING,
543 		sizeof(str));
544 	hub->manufacturer_len = strlen(str) & 0xFF;
545 	memset(hub->manufacturer, 0, USB251XB_STRING_BUFSIZE);
546 	len = min_t(size_t, USB251XB_STRING_BUFSIZE / 2, strlen(str));
547 	len = utf8s_to_utf16s(str, len, UTF16_LITTLE_ENDIAN,
548 			      (wchar_t *)hub->manufacturer,
549 			      USB251XB_STRING_BUFSIZE);
550 
551 	cproperty_char = of_get_property(np, "product", NULL);
552 	strlcpy(str, cproperty_char ? : data->product_str, sizeof(str));
553 	hub->product_len = strlen(str) & 0xFF;
554 	memset(hub->product, 0, USB251XB_STRING_BUFSIZE);
555 	len = min_t(size_t, USB251XB_STRING_BUFSIZE / 2, strlen(str));
556 	len = utf8s_to_utf16s(str, len, UTF16_LITTLE_ENDIAN,
557 			      (wchar_t *)hub->product,
558 			      USB251XB_STRING_BUFSIZE);
559 
560 	cproperty_char = of_get_property(np, "serial", NULL);
561 	strlcpy(str, cproperty_char ? : USB251XB_DEF_SERIAL_STRING,
562 		sizeof(str));
563 	hub->serial_len = strlen(str) & 0xFF;
564 	memset(hub->serial, 0, USB251XB_STRING_BUFSIZE);
565 	len = min_t(size_t, USB251XB_STRING_BUFSIZE / 2, strlen(str));
566 	len = utf8s_to_utf16s(str, len, UTF16_LITTLE_ENDIAN,
567 			      (wchar_t *)hub->serial,
568 			      USB251XB_STRING_BUFSIZE);
569 
570 	/*
571 	 * The datasheet documents the register as 'Port Swap' but in real the
572 	 * register controls the USB DP/DM signal swapping for each port.
573 	 */
574 	hub->port_swap = USB251XB_DEF_PORT_SWAP;
575 	usb251xb_get_ports_field(hub, "swap-dx-lanes", data->port_cnt,
576 				 &hub->port_swap);
577 	if (of_get_property(np, "swap-us-lanes", NULL))
578 		hub->port_swap |= BIT(0);
579 
580 	/* The following parameters are currently not exposed to devicetree, but
581 	 * may be as soon as needed.
582 	 */
583 	hub->bat_charge_en = USB251XB_DEF_BATTERY_CHARGING_ENABLE;
584 	hub->boost_up = USB251XB_DEF_BOOST_UP;
585 	hub->boost_57 = USB251XB_DEF_BOOST_57;
586 	hub->boost_14 = USB251XB_DEF_BOOST_14;
587 	hub->port_map12 = USB251XB_DEF_PORT_MAP_12;
588 	hub->port_map34 = USB251XB_DEF_PORT_MAP_34;
589 	hub->port_map56 = USB251XB_DEF_PORT_MAP_56;
590 	hub->port_map7  = USB251XB_DEF_PORT_MAP_7;
591 
592 	return 0;
593 }
594 
595 static const struct of_device_id usb251xb_of_match[] = {
596 	{
597 		.compatible = "microchip,usb2512b",
598 		.data = &usb2512b_data,
599 	}, {
600 		.compatible = "microchip,usb2512bi",
601 		.data = &usb2512bi_data,
602 	}, {
603 		.compatible = "microchip,usb2513b",
604 		.data = &usb2513b_data,
605 	}, {
606 		.compatible = "microchip,usb2513bi",
607 		.data = &usb2513bi_data,
608 	}, {
609 		.compatible = "microchip,usb2514b",
610 		.data = &usb2514b_data,
611 	}, {
612 		.compatible = "microchip,usb2514bi",
613 		.data = &usb2514bi_data,
614 	}, {
615 		.compatible = "microchip,usb2517",
616 		.data = &usb2517_data,
617 	}, {
618 		.compatible = "microchip,usb2517i",
619 		.data = &usb2517i_data,
620 	}, {
621 		/* sentinel */
622 	}
623 };
624 MODULE_DEVICE_TABLE(of, usb251xb_of_match);
625 #else /* CONFIG_OF */
626 static int usb251xb_get_ofdata(struct usb251xb *hub,
627 			       struct usb251xb_data *data)
628 {
629 	return 0;
630 }
631 #endif /* CONFIG_OF */
632 
633 static int usb251xb_probe(struct usb251xb *hub)
634 {
635 	struct device *dev = hub->dev;
636 	struct device_node *np = dev->of_node;
637 	const struct of_device_id *of_id = of_match_device(usb251xb_of_match,
638 							   dev);
639 	int err;
640 
641 	if (np && of_id) {
642 		err = usb251xb_get_ofdata(hub,
643 					  (struct usb251xb_data *)of_id->data);
644 		if (err) {
645 			dev_err(dev, "failed to get ofdata: %d\n", err);
646 			return err;
647 		}
648 	}
649 
650 	/*
651 	 * usb251x SMBus-slave SCL lane is muxed with CFG_SEL0 pin. So if anyone
652 	 * tries to work with the bus at the moment the hub reset is released,
653 	 * it may cause an invalid config being latched by usb251x. Particularly
654 	 * one of the config modes makes the hub loading a default registers
655 	 * value without SMBus-slave interface activation. If the hub
656 	 * accidentally gets this mode, this will cause the driver SMBus-
657 	 * functions failure. Normally we could just lock the SMBus-segment the
658 	 * hub i2c-interface resides for the device-specific reset timing. But
659 	 * the GPIO controller, which is used to handle the hub reset, might be
660 	 * placed at the same i2c-bus segment. In this case an error should be
661 	 * returned since we can't safely use the GPIO controller to clear the
662 	 * reset state (it may affect the hub configuration) and we can't lock
663 	 * the i2c-bus segment (it will cause a deadlock).
664 	 */
665 	err = usb251x_check_gpio_chip(hub);
666 	if (err)
667 		return err;
668 
669 	err = usb251xb_connect(hub);
670 	if (err) {
671 		dev_err(dev, "Failed to connect hub (%d)\n", err);
672 		return err;
673 	}
674 
675 	dev_info(dev, "Hub probed successfully\n");
676 
677 	return 0;
678 }
679 
680 static int usb251xb_i2c_probe(struct i2c_client *i2c,
681 			      const struct i2c_device_id *id)
682 {
683 	struct usb251xb *hub;
684 
685 	hub = devm_kzalloc(&i2c->dev, sizeof(struct usb251xb), GFP_KERNEL);
686 	if (!hub)
687 		return -ENOMEM;
688 
689 	i2c_set_clientdata(i2c, hub);
690 	hub->dev = &i2c->dev;
691 	hub->i2c = i2c;
692 
693 	return usb251xb_probe(hub);
694 }
695 
696 static const struct i2c_device_id usb251xb_id[] = {
697 	{ "usb2512b", 0 },
698 	{ "usb2512bi", 0 },
699 	{ "usb2513b", 0 },
700 	{ "usb2513bi", 0 },
701 	{ "usb2514b", 0 },
702 	{ "usb2514bi", 0 },
703 	{ "usb2517", 0 },
704 	{ "usb2517i", 0 },
705 	{ /* sentinel */ }
706 };
707 MODULE_DEVICE_TABLE(i2c, usb251xb_id);
708 
709 static struct i2c_driver usb251xb_i2c_driver = {
710 	.driver = {
711 		.name = DRIVER_NAME,
712 		.of_match_table = of_match_ptr(usb251xb_of_match),
713 	},
714 	.probe    = usb251xb_i2c_probe,
715 	.id_table = usb251xb_id,
716 };
717 
718 module_i2c_driver(usb251xb_i2c_driver);
719 
720 MODULE_AUTHOR("Richard Leitner <richard.leitner@skidata.com>");
721 MODULE_DESCRIPTION("USB251x/xBi USB 2.0 Hub Controller Driver");
722 MODULE_LICENSE("GPL");
723