1 /*
2 * ISP1704 USB Charger Detection driver
3 *
4 * Copyright (C) 2010 Nokia Corporation
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/err.h>
24 #include <linux/init.h>
25 #include <linux/types.h>
26 #include <linux/device.h>
27 #include <linux/sysfs.h>
28 #include <linux/platform_device.h>
29 #include <linux/power_supply.h>
30 #include <linux/delay.h>
31
32 #include <linux/usb/otg.h>
33 #include <linux/usb/ulpi.h>
34 #include <linux/usb/ch9.h>
35 #include <linux/usb/gadget.h>
36 #include <linux/power/isp1704_charger.h>
37
38 /* Vendor specific Power Control register */
39 #define ISP1704_PWR_CTRL 0x3d
40 #define ISP1704_PWR_CTRL_SWCTRL (1 << 0)
41 #define ISP1704_PWR_CTRL_DET_COMP (1 << 1)
42 #define ISP1704_PWR_CTRL_BVALID_RISE (1 << 2)
43 #define ISP1704_PWR_CTRL_BVALID_FALL (1 << 3)
44 #define ISP1704_PWR_CTRL_DP_WKPU_EN (1 << 4)
45 #define ISP1704_PWR_CTRL_VDAT_DET (1 << 5)
46 #define ISP1704_PWR_CTRL_DPVSRC_EN (1 << 6)
47 #define ISP1704_PWR_CTRL_HWDETECT (1 << 7)
48
49 #define NXP_VENDOR_ID 0x04cc
50
51 static u16 isp170x_id[] = {
52 0x1704,
53 0x1707,
54 };
55
56 struct isp1704_charger {
57 struct device *dev;
58 struct power_supply psy;
59 struct otg_transceiver *otg;
60 struct notifier_block nb;
61 struct work_struct work;
62
63 /* properties */
64 char model[8];
65 unsigned present:1;
66 unsigned online:1;
67 unsigned current_max;
68
69 /* temp storage variables */
70 unsigned long event;
71 unsigned max_power;
72 };
73
74 /*
75 * Disable/enable the power from the isp1704 if a function for it
76 * has been provided with platform data.
77 */
isp1704_charger_set_power(struct isp1704_charger * isp,bool on)78 static void isp1704_charger_set_power(struct isp1704_charger *isp, bool on)
79 {
80 struct isp1704_charger_data *board = isp->dev->platform_data;
81
82 if (board && board->set_power)
83 board->set_power(on);
84 }
85
86 /*
87 * Determine is the charging port DCP (dedicated charger) or CDP (Host/HUB
88 * chargers).
89 *
90 * REVISIT: The method is defined in Battery Charging Specification and is
91 * applicable to any ULPI transceiver. Nothing isp170x specific here.
92 */
isp1704_charger_type(struct isp1704_charger * isp)93 static inline int isp1704_charger_type(struct isp1704_charger *isp)
94 {
95 u8 reg;
96 u8 func_ctrl;
97 u8 otg_ctrl;
98 int type = POWER_SUPPLY_TYPE_USB_DCP;
99
100 func_ctrl = otg_io_read(isp->otg, ULPI_FUNC_CTRL);
101 otg_ctrl = otg_io_read(isp->otg, ULPI_OTG_CTRL);
102
103 /* disable pulldowns */
104 reg = ULPI_OTG_CTRL_DM_PULLDOWN | ULPI_OTG_CTRL_DP_PULLDOWN;
105 otg_io_write(isp->otg, ULPI_CLR(ULPI_OTG_CTRL), reg);
106
107 /* full speed */
108 otg_io_write(isp->otg, ULPI_CLR(ULPI_FUNC_CTRL),
109 ULPI_FUNC_CTRL_XCVRSEL_MASK);
110 otg_io_write(isp->otg, ULPI_SET(ULPI_FUNC_CTRL),
111 ULPI_FUNC_CTRL_FULL_SPEED);
112
113 /* Enable strong pull-up on DP (1.5K) and reset */
114 reg = ULPI_FUNC_CTRL_TERMSELECT | ULPI_FUNC_CTRL_RESET;
115 otg_io_write(isp->otg, ULPI_SET(ULPI_FUNC_CTRL), reg);
116 usleep_range(1000, 2000);
117
118 reg = otg_io_read(isp->otg, ULPI_DEBUG);
119 if ((reg & 3) != 3)
120 type = POWER_SUPPLY_TYPE_USB_CDP;
121
122 /* recover original state */
123 otg_io_write(isp->otg, ULPI_FUNC_CTRL, func_ctrl);
124 otg_io_write(isp->otg, ULPI_OTG_CTRL, otg_ctrl);
125
126 return type;
127 }
128
129 /*
130 * ISP1704 detects PS/2 adapters as charger. To make sure the detected charger
131 * is actually a dedicated charger, the following steps need to be taken.
132 */
isp1704_charger_verify(struct isp1704_charger * isp)133 static inline int isp1704_charger_verify(struct isp1704_charger *isp)
134 {
135 int ret = 0;
136 u8 r;
137
138 /* Reset the transceiver */
139 r = otg_io_read(isp->otg, ULPI_FUNC_CTRL);
140 r |= ULPI_FUNC_CTRL_RESET;
141 otg_io_write(isp->otg, ULPI_FUNC_CTRL, r);
142 usleep_range(1000, 2000);
143
144 /* Set normal mode */
145 r &= ~(ULPI_FUNC_CTRL_RESET | ULPI_FUNC_CTRL_OPMODE_MASK);
146 otg_io_write(isp->otg, ULPI_FUNC_CTRL, r);
147
148 /* Clear the DP and DM pull-down bits */
149 r = ULPI_OTG_CTRL_DP_PULLDOWN | ULPI_OTG_CTRL_DM_PULLDOWN;
150 otg_io_write(isp->otg, ULPI_CLR(ULPI_OTG_CTRL), r);
151
152 /* Enable strong pull-up on DP (1.5K) and reset */
153 r = ULPI_FUNC_CTRL_TERMSELECT | ULPI_FUNC_CTRL_RESET;
154 otg_io_write(isp->otg, ULPI_SET(ULPI_FUNC_CTRL), r);
155 usleep_range(1000, 2000);
156
157 /* Read the line state */
158 if (!otg_io_read(isp->otg, ULPI_DEBUG)) {
159 /* Disable strong pull-up on DP (1.5K) */
160 otg_io_write(isp->otg, ULPI_CLR(ULPI_FUNC_CTRL),
161 ULPI_FUNC_CTRL_TERMSELECT);
162 return 1;
163 }
164
165 /* Is it a charger or PS/2 connection */
166
167 /* Enable weak pull-up resistor on DP */
168 otg_io_write(isp->otg, ULPI_SET(ISP1704_PWR_CTRL),
169 ISP1704_PWR_CTRL_DP_WKPU_EN);
170
171 /* Disable strong pull-up on DP (1.5K) */
172 otg_io_write(isp->otg, ULPI_CLR(ULPI_FUNC_CTRL),
173 ULPI_FUNC_CTRL_TERMSELECT);
174
175 /* Enable weak pull-down resistor on DM */
176 otg_io_write(isp->otg, ULPI_SET(ULPI_OTG_CTRL),
177 ULPI_OTG_CTRL_DM_PULLDOWN);
178
179 /* It's a charger if the line states are clear */
180 if (!(otg_io_read(isp->otg, ULPI_DEBUG)))
181 ret = 1;
182
183 /* Disable weak pull-up resistor on DP */
184 otg_io_write(isp->otg, ULPI_CLR(ISP1704_PWR_CTRL),
185 ISP1704_PWR_CTRL_DP_WKPU_EN);
186
187 return ret;
188 }
189
isp1704_charger_detect(struct isp1704_charger * isp)190 static inline int isp1704_charger_detect(struct isp1704_charger *isp)
191 {
192 unsigned long timeout;
193 u8 pwr_ctrl;
194 int ret = 0;
195
196 pwr_ctrl = otg_io_read(isp->otg, ISP1704_PWR_CTRL);
197
198 /* set SW control bit in PWR_CTRL register */
199 otg_io_write(isp->otg, ISP1704_PWR_CTRL,
200 ISP1704_PWR_CTRL_SWCTRL);
201
202 /* enable manual charger detection */
203 otg_io_write(isp->otg, ULPI_SET(ISP1704_PWR_CTRL),
204 ISP1704_PWR_CTRL_SWCTRL
205 | ISP1704_PWR_CTRL_DPVSRC_EN);
206 usleep_range(1000, 2000);
207
208 timeout = jiffies + msecs_to_jiffies(300);
209 do {
210 /* Check if there is a charger */
211 if (otg_io_read(isp->otg, ISP1704_PWR_CTRL)
212 & ISP1704_PWR_CTRL_VDAT_DET) {
213 ret = isp1704_charger_verify(isp);
214 break;
215 }
216 } while (!time_after(jiffies, timeout) && isp->online);
217
218 /* recover original state */
219 otg_io_write(isp->otg, ISP1704_PWR_CTRL, pwr_ctrl);
220
221 return ret;
222 }
223
isp1704_charger_work(struct work_struct * data)224 static void isp1704_charger_work(struct work_struct *data)
225 {
226 int detect;
227 unsigned long event;
228 unsigned power;
229 struct isp1704_charger *isp =
230 container_of(data, struct isp1704_charger, work);
231 static DEFINE_MUTEX(lock);
232
233 event = isp->event;
234 power = isp->max_power;
235
236 mutex_lock(&lock);
237
238 if (event != USB_EVENT_NONE)
239 isp1704_charger_set_power(isp, 1);
240
241 switch (event) {
242 case USB_EVENT_VBUS:
243 isp->online = true;
244
245 /* detect charger */
246 detect = isp1704_charger_detect(isp);
247
248 if (detect) {
249 isp->present = detect;
250 isp->psy.type = isp1704_charger_type(isp);
251 }
252
253 switch (isp->psy.type) {
254 case POWER_SUPPLY_TYPE_USB_DCP:
255 isp->current_max = 1800;
256 break;
257 case POWER_SUPPLY_TYPE_USB_CDP:
258 /*
259 * Only 500mA here or high speed chirp
260 * handshaking may break
261 */
262 isp->current_max = 500;
263 /* FALLTHROUGH */
264 case POWER_SUPPLY_TYPE_USB:
265 default:
266 /* enable data pullups */
267 if (isp->otg->gadget)
268 usb_gadget_connect(isp->otg->gadget);
269 }
270 break;
271 case USB_EVENT_NONE:
272 isp->online = false;
273 isp->current_max = 0;
274 isp->present = 0;
275 isp->current_max = 0;
276 isp->psy.type = POWER_SUPPLY_TYPE_USB;
277
278 /*
279 * Disable data pullups. We need to prevent the controller from
280 * enumerating.
281 *
282 * FIXME: This is here to allow charger detection with Host/HUB
283 * chargers. The pullups may be enabled elsewhere, so this can
284 * not be the final solution.
285 */
286 if (isp->otg->gadget)
287 usb_gadget_disconnect(isp->otg->gadget);
288
289 isp1704_charger_set_power(isp, 0);
290 break;
291 case USB_EVENT_ENUMERATED:
292 if (isp->present)
293 isp->current_max = 1800;
294 else
295 isp->current_max = power;
296 break;
297 default:
298 goto out;
299 }
300
301 power_supply_changed(&isp->psy);
302 out:
303 mutex_unlock(&lock);
304 }
305
isp1704_notifier_call(struct notifier_block * nb,unsigned long event,void * power)306 static int isp1704_notifier_call(struct notifier_block *nb,
307 unsigned long event, void *power)
308 {
309 struct isp1704_charger *isp =
310 container_of(nb, struct isp1704_charger, nb);
311
312 isp->event = event;
313
314 if (power)
315 isp->max_power = *((unsigned *)power);
316
317 schedule_work(&isp->work);
318
319 return NOTIFY_OK;
320 }
321
isp1704_charger_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)322 static int isp1704_charger_get_property(struct power_supply *psy,
323 enum power_supply_property psp,
324 union power_supply_propval *val)
325 {
326 struct isp1704_charger *isp =
327 container_of(psy, struct isp1704_charger, psy);
328
329 switch (psp) {
330 case POWER_SUPPLY_PROP_PRESENT:
331 val->intval = isp->present;
332 break;
333 case POWER_SUPPLY_PROP_ONLINE:
334 val->intval = isp->online;
335 break;
336 case POWER_SUPPLY_PROP_CURRENT_MAX:
337 val->intval = isp->current_max;
338 break;
339 case POWER_SUPPLY_PROP_MODEL_NAME:
340 val->strval = isp->model;
341 break;
342 case POWER_SUPPLY_PROP_MANUFACTURER:
343 val->strval = "NXP";
344 break;
345 default:
346 return -EINVAL;
347 }
348 return 0;
349 }
350
351 static enum power_supply_property power_props[] = {
352 POWER_SUPPLY_PROP_PRESENT,
353 POWER_SUPPLY_PROP_ONLINE,
354 POWER_SUPPLY_PROP_CURRENT_MAX,
355 POWER_SUPPLY_PROP_MODEL_NAME,
356 POWER_SUPPLY_PROP_MANUFACTURER,
357 };
358
isp1704_test_ulpi(struct isp1704_charger * isp)359 static inline int isp1704_test_ulpi(struct isp1704_charger *isp)
360 {
361 int vendor;
362 int product;
363 int i;
364 int ret = -ENODEV;
365
366 /* Test ULPI interface */
367 ret = otg_io_write(isp->otg, ULPI_SCRATCH, 0xaa);
368 if (ret < 0)
369 return ret;
370
371 ret = otg_io_read(isp->otg, ULPI_SCRATCH);
372 if (ret < 0)
373 return ret;
374
375 if (ret != 0xaa)
376 return -ENODEV;
377
378 /* Verify the product and vendor id matches */
379 vendor = otg_io_read(isp->otg, ULPI_VENDOR_ID_LOW);
380 vendor |= otg_io_read(isp->otg, ULPI_VENDOR_ID_HIGH) << 8;
381 if (vendor != NXP_VENDOR_ID)
382 return -ENODEV;
383
384 product = otg_io_read(isp->otg, ULPI_PRODUCT_ID_LOW);
385 product |= otg_io_read(isp->otg, ULPI_PRODUCT_ID_HIGH) << 8;
386
387 for (i = 0; i < ARRAY_SIZE(isp170x_id); i++) {
388 if (product == isp170x_id[i]) {
389 sprintf(isp->model, "isp%x", product);
390 return product;
391 }
392 }
393
394 dev_err(isp->dev, "product id %x not matching known ids", product);
395
396 return -ENODEV;
397 }
398
isp1704_charger_probe(struct platform_device * pdev)399 static int __devinit isp1704_charger_probe(struct platform_device *pdev)
400 {
401 struct isp1704_charger *isp;
402 int ret = -ENODEV;
403
404 isp = kzalloc(sizeof *isp, GFP_KERNEL);
405 if (!isp)
406 return -ENOMEM;
407
408 isp->otg = otg_get_transceiver();
409 if (!isp->otg)
410 goto fail0;
411
412 isp->dev = &pdev->dev;
413 platform_set_drvdata(pdev, isp);
414
415 isp1704_charger_set_power(isp, 1);
416
417 ret = isp1704_test_ulpi(isp);
418 if (ret < 0)
419 goto fail1;
420
421 isp->psy.name = "isp1704";
422 isp->psy.type = POWER_SUPPLY_TYPE_USB;
423 isp->psy.properties = power_props;
424 isp->psy.num_properties = ARRAY_SIZE(power_props);
425 isp->psy.get_property = isp1704_charger_get_property;
426
427 ret = power_supply_register(isp->dev, &isp->psy);
428 if (ret)
429 goto fail1;
430
431 /*
432 * REVISIT: using work in order to allow the otg notifications to be
433 * made atomically in the future.
434 */
435 INIT_WORK(&isp->work, isp1704_charger_work);
436
437 isp->nb.notifier_call = isp1704_notifier_call;
438
439 ret = otg_register_notifier(isp->otg, &isp->nb);
440 if (ret)
441 goto fail2;
442
443 dev_info(isp->dev, "registered with product id %s\n", isp->model);
444
445 /*
446 * Taking over the D+ pullup.
447 *
448 * FIXME: The device will be disconnected if it was already
449 * enumerated. The charger driver should be always loaded before any
450 * gadget is loaded.
451 */
452 if (isp->otg->gadget)
453 usb_gadget_disconnect(isp->otg->gadget);
454
455 /* Detect charger if VBUS is valid (the cable was already plugged). */
456 ret = otg_io_read(isp->otg, ULPI_USB_INT_STS);
457 isp1704_charger_set_power(isp, 0);
458 if ((ret & ULPI_INT_VBUS_VALID) && !isp->otg->default_a) {
459 isp->event = USB_EVENT_VBUS;
460 schedule_work(&isp->work);
461 }
462
463 return 0;
464 fail2:
465 power_supply_unregister(&isp->psy);
466 fail1:
467 otg_put_transceiver(isp->otg);
468 fail0:
469 kfree(isp);
470
471 dev_err(&pdev->dev, "failed to register isp1704 with error %d\n", ret);
472
473 return ret;
474 }
475
isp1704_charger_remove(struct platform_device * pdev)476 static int __devexit isp1704_charger_remove(struct platform_device *pdev)
477 {
478 struct isp1704_charger *isp = platform_get_drvdata(pdev);
479
480 otg_unregister_notifier(isp->otg, &isp->nb);
481 power_supply_unregister(&isp->psy);
482 otg_put_transceiver(isp->otg);
483 isp1704_charger_set_power(isp, 0);
484 kfree(isp);
485
486 return 0;
487 }
488
489 static struct platform_driver isp1704_charger_driver = {
490 .driver = {
491 .name = "isp1704_charger",
492 },
493 .probe = isp1704_charger_probe,
494 .remove = __devexit_p(isp1704_charger_remove),
495 };
496
497 module_platform_driver(isp1704_charger_driver);
498
499 MODULE_ALIAS("platform:isp1704_charger");
500 MODULE_AUTHOR("Nokia Corporation");
501 MODULE_DESCRIPTION("ISP170x USB Charger driver");
502 MODULE_LICENSE("GPL");
503