Merge tag 'spi-v4.1-rc1' into spi-linus
[firefly-linux-kernel-4.4.55.git] / drivers / power / isp1704_charger.c
1 /*
2  * ISP1704 USB Charger Detection driver
3  *
4  * Copyright (C) 2010 Nokia Corporation
5  * Copyright (C) 2012 - 2013 Pali Rohár <pali.rohar@gmail.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20  */
21
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/err.h>
25 #include <linux/init.h>
26 #include <linux/types.h>
27 #include <linux/device.h>
28 #include <linux/sysfs.h>
29 #include <linux/platform_device.h>
30 #include <linux/power_supply.h>
31 #include <linux/delay.h>
32 #include <linux/of.h>
33 #include <linux/of_gpio.h>
34
35 #include <linux/usb/otg.h>
36 #include <linux/usb/ulpi.h>
37 #include <linux/usb/ch9.h>
38 #include <linux/usb/gadget.h>
39 #include <linux/power/isp1704_charger.h>
40
41 /* Vendor specific Power Control register */
42 #define ISP1704_PWR_CTRL                0x3d
43 #define ISP1704_PWR_CTRL_SWCTRL         (1 << 0)
44 #define ISP1704_PWR_CTRL_DET_COMP       (1 << 1)
45 #define ISP1704_PWR_CTRL_BVALID_RISE    (1 << 2)
46 #define ISP1704_PWR_CTRL_BVALID_FALL    (1 << 3)
47 #define ISP1704_PWR_CTRL_DP_WKPU_EN     (1 << 4)
48 #define ISP1704_PWR_CTRL_VDAT_DET       (1 << 5)
49 #define ISP1704_PWR_CTRL_DPVSRC_EN      (1 << 6)
50 #define ISP1704_PWR_CTRL_HWDETECT       (1 << 7)
51
52 #define NXP_VENDOR_ID                   0x04cc
53
54 static u16 isp170x_id[] = {
55         0x1704,
56         0x1707,
57 };
58
59 struct isp1704_charger {
60         struct device                   *dev;
61         struct power_supply             *psy;
62         struct power_supply_desc        psy_desc;
63         struct usb_phy                  *phy;
64         struct notifier_block           nb;
65         struct work_struct              work;
66
67         /* properties */
68         char                    model[8];
69         unsigned                present:1;
70         unsigned                online:1;
71         unsigned                current_max;
72 };
73
74 static inline int isp1704_read(struct isp1704_charger *isp, u32 reg)
75 {
76         return usb_phy_io_read(isp->phy, reg);
77 }
78
79 static inline int isp1704_write(struct isp1704_charger *isp, u32 val, u32 reg)
80 {
81         return usb_phy_io_write(isp->phy, val, reg);
82 }
83
84 /*
85  * Disable/enable the power from the isp1704 if a function for it
86  * has been provided with platform data.
87  */
88 static void isp1704_charger_set_power(struct isp1704_charger *isp, bool on)
89 {
90         struct isp1704_charger_data     *board = isp->dev->platform_data;
91
92         if (board && board->set_power)
93                 board->set_power(on);
94         else if (board)
95                 gpio_set_value(board->enable_gpio, on);
96 }
97
98 /*
99  * Determine is the charging port DCP (dedicated charger) or CDP (Host/HUB
100  * chargers).
101  *
102  * REVISIT: The method is defined in Battery Charging Specification and is
103  * applicable to any ULPI transceiver. Nothing isp170x specific here.
104  */
105 static inline int isp1704_charger_type(struct isp1704_charger *isp)
106 {
107         u8 reg;
108         u8 func_ctrl;
109         u8 otg_ctrl;
110         int type = POWER_SUPPLY_TYPE_USB_DCP;
111
112         func_ctrl = isp1704_read(isp, ULPI_FUNC_CTRL);
113         otg_ctrl = isp1704_read(isp, ULPI_OTG_CTRL);
114
115         /* disable pulldowns */
116         reg = ULPI_OTG_CTRL_DM_PULLDOWN | ULPI_OTG_CTRL_DP_PULLDOWN;
117         isp1704_write(isp, ULPI_CLR(ULPI_OTG_CTRL), reg);
118
119         /* full speed */
120         isp1704_write(isp, ULPI_CLR(ULPI_FUNC_CTRL),
121                         ULPI_FUNC_CTRL_XCVRSEL_MASK);
122         isp1704_write(isp, ULPI_SET(ULPI_FUNC_CTRL),
123                         ULPI_FUNC_CTRL_FULL_SPEED);
124
125         /* Enable strong pull-up on DP (1.5K) and reset */
126         reg = ULPI_FUNC_CTRL_TERMSELECT | ULPI_FUNC_CTRL_RESET;
127         isp1704_write(isp, ULPI_SET(ULPI_FUNC_CTRL), reg);
128         usleep_range(1000, 2000);
129
130         reg = isp1704_read(isp, ULPI_DEBUG);
131         if ((reg & 3) != 3)
132                 type = POWER_SUPPLY_TYPE_USB_CDP;
133
134         /* recover original state */
135         isp1704_write(isp, ULPI_FUNC_CTRL, func_ctrl);
136         isp1704_write(isp, ULPI_OTG_CTRL, otg_ctrl);
137
138         return type;
139 }
140
141 /*
142  * ISP1704 detects PS/2 adapters as charger. To make sure the detected charger
143  * is actually a dedicated charger, the following steps need to be taken.
144  */
145 static inline int isp1704_charger_verify(struct isp1704_charger *isp)
146 {
147         int     ret = 0;
148         u8      r;
149
150         /* Reset the transceiver */
151         r = isp1704_read(isp, ULPI_FUNC_CTRL);
152         r |= ULPI_FUNC_CTRL_RESET;
153         isp1704_write(isp, ULPI_FUNC_CTRL, r);
154         usleep_range(1000, 2000);
155
156         /* Set normal mode */
157         r &= ~(ULPI_FUNC_CTRL_RESET | ULPI_FUNC_CTRL_OPMODE_MASK);
158         isp1704_write(isp, ULPI_FUNC_CTRL, r);
159
160         /* Clear the DP and DM pull-down bits */
161         r = ULPI_OTG_CTRL_DP_PULLDOWN | ULPI_OTG_CTRL_DM_PULLDOWN;
162         isp1704_write(isp, ULPI_CLR(ULPI_OTG_CTRL), r);
163
164         /* Enable strong pull-up on DP (1.5K) and reset */
165         r = ULPI_FUNC_CTRL_TERMSELECT | ULPI_FUNC_CTRL_RESET;
166         isp1704_write(isp, ULPI_SET(ULPI_FUNC_CTRL), r);
167         usleep_range(1000, 2000);
168
169         /* Read the line state */
170         if (!isp1704_read(isp, ULPI_DEBUG)) {
171                 /* Disable strong pull-up on DP (1.5K) */
172                 isp1704_write(isp, ULPI_CLR(ULPI_FUNC_CTRL),
173                                 ULPI_FUNC_CTRL_TERMSELECT);
174                 return 1;
175         }
176
177         /* Is it a charger or PS/2 connection */
178
179         /* Enable weak pull-up resistor on DP */
180         isp1704_write(isp, ULPI_SET(ISP1704_PWR_CTRL),
181                         ISP1704_PWR_CTRL_DP_WKPU_EN);
182
183         /* Disable strong pull-up on DP (1.5K) */
184         isp1704_write(isp, ULPI_CLR(ULPI_FUNC_CTRL),
185                         ULPI_FUNC_CTRL_TERMSELECT);
186
187         /* Enable weak pull-down resistor on DM */
188         isp1704_write(isp, ULPI_SET(ULPI_OTG_CTRL),
189                         ULPI_OTG_CTRL_DM_PULLDOWN);
190
191         /* It's a charger if the line states are clear */
192         if (!(isp1704_read(isp, ULPI_DEBUG)))
193                 ret = 1;
194
195         /* Disable weak pull-up resistor on DP */
196         isp1704_write(isp, ULPI_CLR(ISP1704_PWR_CTRL),
197                         ISP1704_PWR_CTRL_DP_WKPU_EN);
198
199         return ret;
200 }
201
202 static inline int isp1704_charger_detect(struct isp1704_charger *isp)
203 {
204         unsigned long   timeout;
205         u8              pwr_ctrl;
206         int             ret = 0;
207
208         pwr_ctrl = isp1704_read(isp, ISP1704_PWR_CTRL);
209
210         /* set SW control bit in PWR_CTRL register */
211         isp1704_write(isp, ISP1704_PWR_CTRL,
212                         ISP1704_PWR_CTRL_SWCTRL);
213
214         /* enable manual charger detection */
215         isp1704_write(isp, ULPI_SET(ISP1704_PWR_CTRL),
216                         ISP1704_PWR_CTRL_SWCTRL
217                         | ISP1704_PWR_CTRL_DPVSRC_EN);
218         usleep_range(1000, 2000);
219
220         timeout = jiffies + msecs_to_jiffies(300);
221         do {
222                 /* Check if there is a charger */
223                 if (isp1704_read(isp, ISP1704_PWR_CTRL)
224                                 & ISP1704_PWR_CTRL_VDAT_DET) {
225                         ret = isp1704_charger_verify(isp);
226                         break;
227                 }
228         } while (!time_after(jiffies, timeout) && isp->online);
229
230         /* recover original state */
231         isp1704_write(isp, ISP1704_PWR_CTRL, pwr_ctrl);
232
233         return ret;
234 }
235
236 static inline int isp1704_charger_detect_dcp(struct isp1704_charger *isp)
237 {
238         if (isp1704_charger_detect(isp) &&
239                         isp1704_charger_type(isp) == POWER_SUPPLY_TYPE_USB_DCP)
240                 return true;
241         else
242                 return false;
243 }
244
245 static void isp1704_charger_work(struct work_struct *data)
246 {
247         struct isp1704_charger  *isp =
248                 container_of(data, struct isp1704_charger, work);
249         static DEFINE_MUTEX(lock);
250
251         mutex_lock(&lock);
252
253         switch (isp->phy->last_event) {
254         case USB_EVENT_VBUS:
255                 /* do not call wall charger detection more times */
256                 if (!isp->present) {
257                         isp->online = true;
258                         isp->present = 1;
259                         isp1704_charger_set_power(isp, 1);
260
261                         /* detect wall charger */
262                         if (isp1704_charger_detect_dcp(isp)) {
263                                 isp->psy_desc.type = POWER_SUPPLY_TYPE_USB_DCP;
264                                 isp->current_max = 1800;
265                         } else {
266                                 isp->psy_desc.type = POWER_SUPPLY_TYPE_USB;
267                                 isp->current_max = 500;
268                         }
269
270                         /* enable data pullups */
271                         if (isp->phy->otg->gadget)
272                                 usb_gadget_connect(isp->phy->otg->gadget);
273                 }
274
275                 if (isp->psy_desc.type != POWER_SUPPLY_TYPE_USB_DCP) {
276                         /*
277                          * Only 500mA here or high speed chirp
278                          * handshaking may break
279                          */
280                         if (isp->current_max > 500)
281                                 isp->current_max = 500;
282
283                         if (isp->current_max > 100)
284                                 isp->psy_desc.type = POWER_SUPPLY_TYPE_USB_CDP;
285                 }
286                 break;
287         case USB_EVENT_NONE:
288                 isp->online = false;
289                 isp->present = 0;
290                 isp->current_max = 0;
291                 isp->psy_desc.type = POWER_SUPPLY_TYPE_USB;
292
293                 /*
294                  * Disable data pullups. We need to prevent the controller from
295                  * enumerating.
296                  *
297                  * FIXME: This is here to allow charger detection with Host/HUB
298                  * chargers. The pullups may be enabled elsewhere, so this can
299                  * not be the final solution.
300                  */
301                 if (isp->phy->otg->gadget)
302                         usb_gadget_disconnect(isp->phy->otg->gadget);
303
304                 isp1704_charger_set_power(isp, 0);
305                 break;
306         default:
307                 goto out;
308         }
309
310         power_supply_changed(isp->psy);
311 out:
312         mutex_unlock(&lock);
313 }
314
315 static int isp1704_notifier_call(struct notifier_block *nb,
316                 unsigned long val, void *v)
317 {
318         struct isp1704_charger *isp =
319                 container_of(nb, struct isp1704_charger, nb);
320
321         schedule_work(&isp->work);
322
323         return NOTIFY_OK;
324 }
325
326 static int isp1704_charger_get_property(struct power_supply *psy,
327                                 enum power_supply_property psp,
328                                 union power_supply_propval *val)
329 {
330         struct isp1704_charger *isp = power_supply_get_drvdata(psy);
331
332         switch (psp) {
333         case POWER_SUPPLY_PROP_PRESENT:
334                 val->intval = isp->present;
335                 break;
336         case POWER_SUPPLY_PROP_ONLINE:
337                 val->intval = isp->online;
338                 break;
339         case POWER_SUPPLY_PROP_CURRENT_MAX:
340                 val->intval = isp->current_max;
341                 break;
342         case POWER_SUPPLY_PROP_MODEL_NAME:
343                 val->strval = isp->model;
344                 break;
345         case POWER_SUPPLY_PROP_MANUFACTURER:
346                 val->strval = "NXP";
347                 break;
348         default:
349                 return -EINVAL;
350         }
351         return 0;
352 }
353
354 static enum power_supply_property power_props[] = {
355         POWER_SUPPLY_PROP_PRESENT,
356         POWER_SUPPLY_PROP_ONLINE,
357         POWER_SUPPLY_PROP_CURRENT_MAX,
358         POWER_SUPPLY_PROP_MODEL_NAME,
359         POWER_SUPPLY_PROP_MANUFACTURER,
360 };
361
362 static inline int isp1704_test_ulpi(struct isp1704_charger *isp)
363 {
364         int vendor;
365         int product;
366         int i;
367         int ret = -ENODEV;
368
369         /* Test ULPI interface */
370         ret = isp1704_write(isp, ULPI_SCRATCH, 0xaa);
371         if (ret < 0)
372                 return ret;
373
374         ret = isp1704_read(isp, ULPI_SCRATCH);
375         if (ret < 0)
376                 return ret;
377
378         if (ret != 0xaa)
379                 return -ENODEV;
380
381         /* Verify the product and vendor id matches */
382         vendor = isp1704_read(isp, ULPI_VENDOR_ID_LOW);
383         vendor |= isp1704_read(isp, ULPI_VENDOR_ID_HIGH) << 8;
384         if (vendor != NXP_VENDOR_ID)
385                 return -ENODEV;
386
387         product = isp1704_read(isp, ULPI_PRODUCT_ID_LOW);
388         product |= isp1704_read(isp, ULPI_PRODUCT_ID_HIGH) << 8;
389
390         for (i = 0; i < ARRAY_SIZE(isp170x_id); i++) {
391                 if (product == isp170x_id[i]) {
392                         sprintf(isp->model, "isp%x", product);
393                         return product;
394                 }
395         }
396
397         dev_err(isp->dev, "product id %x not matching known ids", product);
398
399         return -ENODEV;
400 }
401
402 static int isp1704_charger_probe(struct platform_device *pdev)
403 {
404         struct isp1704_charger  *isp;
405         int                     ret = -ENODEV;
406         struct power_supply_config psy_cfg = {};
407
408         struct isp1704_charger_data *pdata = dev_get_platdata(&pdev->dev);
409         struct device_node *np = pdev->dev.of_node;
410
411         if (np) {
412                 int gpio = of_get_named_gpio(np, "nxp,enable-gpio", 0);
413
414                 if (gpio < 0)
415                         return gpio;
416
417                 pdata = devm_kzalloc(&pdev->dev,
418                         sizeof(struct isp1704_charger_data), GFP_KERNEL);
419                 pdata->enable_gpio = gpio;
420
421                 dev_info(&pdev->dev, "init gpio %d\n", pdata->enable_gpio);
422
423                 ret = devm_gpio_request_one(&pdev->dev, pdata->enable_gpio,
424                                         GPIOF_OUT_INIT_HIGH, "isp1704_reset");
425                 if (ret)
426                         goto fail0;
427         }
428
429         if (!pdata) {
430                 dev_err(&pdev->dev, "missing platform data!\n");
431                 return -ENODEV;
432         }
433
434
435         isp = devm_kzalloc(&pdev->dev, sizeof(*isp), GFP_KERNEL);
436         if (!isp)
437                 return -ENOMEM;
438
439         if (np)
440                 isp->phy = devm_usb_get_phy_by_phandle(&pdev->dev, "usb-phy", 0);
441         else
442                 isp->phy = devm_usb_get_phy(&pdev->dev, USB_PHY_TYPE_USB2);
443
444         if (IS_ERR(isp->phy)) {
445                 ret = PTR_ERR(isp->phy);
446                 goto fail0;
447         }
448
449         isp->dev = &pdev->dev;
450         platform_set_drvdata(pdev, isp);
451
452         isp1704_charger_set_power(isp, 1);
453
454         ret = isp1704_test_ulpi(isp);
455         if (ret < 0)
456                 goto fail1;
457
458         isp->psy_desc.name              = "isp1704";
459         isp->psy_desc.type              = POWER_SUPPLY_TYPE_USB;
460         isp->psy_desc.properties        = power_props;
461         isp->psy_desc.num_properties    = ARRAY_SIZE(power_props);
462         isp->psy_desc.get_property      = isp1704_charger_get_property;
463
464         psy_cfg.drv_data                = isp;
465
466         isp->psy = power_supply_register(isp->dev, &isp->psy_desc, &psy_cfg);
467         if (IS_ERR(isp->psy)) {
468                 ret = PTR_ERR(isp->psy);
469                 goto fail1;
470         }
471
472         /*
473          * REVISIT: using work in order to allow the usb notifications to be
474          * made atomically in the future.
475          */
476         INIT_WORK(&isp->work, isp1704_charger_work);
477
478         isp->nb.notifier_call = isp1704_notifier_call;
479
480         ret = usb_register_notifier(isp->phy, &isp->nb);
481         if (ret)
482                 goto fail2;
483
484         dev_info(isp->dev, "registered with product id %s\n", isp->model);
485
486         /*
487          * Taking over the D+ pullup.
488          *
489          * FIXME: The device will be disconnected if it was already
490          * enumerated. The charger driver should be always loaded before any
491          * gadget is loaded.
492          */
493         if (isp->phy->otg->gadget)
494                 usb_gadget_disconnect(isp->phy->otg->gadget);
495
496         if (isp->phy->last_event == USB_EVENT_NONE)
497                 isp1704_charger_set_power(isp, 0);
498
499         /* Detect charger if VBUS is valid (the cable was already plugged). */
500         if (isp->phy->last_event == USB_EVENT_VBUS &&
501                         !isp->phy->otg->default_a)
502                 schedule_work(&isp->work);
503
504         return 0;
505 fail2:
506         power_supply_unregister(isp->psy);
507 fail1:
508         isp1704_charger_set_power(isp, 0);
509 fail0:
510         dev_err(&pdev->dev, "failed to register isp1704 with error %d\n", ret);
511
512         return ret;
513 }
514
515 static int isp1704_charger_remove(struct platform_device *pdev)
516 {
517         struct isp1704_charger *isp = platform_get_drvdata(pdev);
518
519         usb_unregister_notifier(isp->phy, &isp->nb);
520         power_supply_unregister(isp->psy);
521         isp1704_charger_set_power(isp, 0);
522
523         return 0;
524 }
525
526 #ifdef CONFIG_OF
527 static const struct of_device_id omap_isp1704_of_match[] = {
528         { .compatible = "nxp,isp1704", },
529         {},
530 };
531 MODULE_DEVICE_TABLE(of, omap_isp1704_of_match);
532 #endif
533
534 static struct platform_driver isp1704_charger_driver = {
535         .driver = {
536                 .name = "isp1704_charger",
537                 .of_match_table = of_match_ptr(omap_isp1704_of_match),
538         },
539         .probe = isp1704_charger_probe,
540         .remove = isp1704_charger_remove,
541 };
542
543 module_platform_driver(isp1704_charger_driver);
544
545 MODULE_ALIAS("platform:isp1704_charger");
546 MODULE_AUTHOR("Nokia Corporation");
547 MODULE_DESCRIPTION("ISP170x USB Charger driver");
548 MODULE_LICENSE("GPL");