1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * ISP1704 USB Charger Detection driver |
4 | * |
5 | * Copyright (C) 2010 Nokia Corporation |
6 | * Copyright (C) 2012 - 2013 Pali Rohár <pali@kernel.org> |
7 | */ |
8 | |
9 | #include <linux/kernel.h> |
10 | #include <linux/module.h> |
11 | #include <linux/err.h> |
12 | #include <linux/init.h> |
13 | #include <linux/types.h> |
14 | #include <linux/device.h> |
15 | #include <linux/sysfs.h> |
16 | #include <linux/platform_device.h> |
17 | #include <linux/power_supply.h> |
18 | #include <linux/delay.h> |
19 | #include <linux/of.h> |
20 | |
21 | #include <linux/gpio/consumer.h> |
22 | #include <linux/usb/otg.h> |
23 | #include <linux/usb/ulpi.h> |
24 | #include <linux/usb/ch9.h> |
25 | #include <linux/usb/gadget.h> |
26 | |
27 | /* Vendor specific Power Control register */ |
28 | #define ISP1704_PWR_CTRL 0x3d |
29 | #define ISP1704_PWR_CTRL_SWCTRL (1 << 0) |
30 | #define ISP1704_PWR_CTRL_DET_COMP (1 << 1) |
31 | #define ISP1704_PWR_CTRL_BVALID_RISE (1 << 2) |
32 | #define ISP1704_PWR_CTRL_BVALID_FALL (1 << 3) |
33 | #define ISP1704_PWR_CTRL_DP_WKPU_EN (1 << 4) |
34 | #define ISP1704_PWR_CTRL_VDAT_DET (1 << 5) |
35 | #define ISP1704_PWR_CTRL_DPVSRC_EN (1 << 6) |
36 | #define ISP1704_PWR_CTRL_HWDETECT (1 << 7) |
37 | |
38 | #define NXP_VENDOR_ID 0x04cc |
39 | |
40 | static u16 isp170x_id[] = { |
41 | 0x1704, |
42 | 0x1707, |
43 | }; |
44 | |
45 | struct isp1704_charger { |
46 | struct device *dev; |
47 | struct power_supply *psy; |
48 | struct power_supply_desc psy_desc; |
49 | struct gpio_desc *enable_gpio; |
50 | struct usb_phy *phy; |
51 | struct notifier_block nb; |
52 | struct work_struct work; |
53 | |
54 | /* properties */ |
55 | char model[8]; |
56 | unsigned present:1; |
57 | unsigned online:1; |
58 | unsigned current_max; |
59 | }; |
60 | |
61 | static inline int isp1704_read(struct isp1704_charger *isp, u32 reg) |
62 | { |
63 | return usb_phy_io_read(x: isp->phy, reg); |
64 | } |
65 | |
66 | static inline int isp1704_write(struct isp1704_charger *isp, u32 reg, u32 val) |
67 | { |
68 | return usb_phy_io_write(x: isp->phy, val, reg); |
69 | } |
70 | |
71 | static void isp1704_charger_set_power(struct isp1704_charger *isp, bool on) |
72 | { |
73 | gpiod_set_value(desc: isp->enable_gpio, value: on); |
74 | } |
75 | |
76 | /* |
77 | * Determine is the charging port DCP (dedicated charger) or CDP (Host/HUB |
78 | * chargers). |
79 | * |
80 | * REVISIT: The method is defined in Battery Charging Specification and is |
81 | * applicable to any ULPI transceiver. Nothing isp170x specific here. |
82 | */ |
83 | static inline int isp1704_charger_type(struct isp1704_charger *isp) |
84 | { |
85 | u8 reg; |
86 | u8 func_ctrl; |
87 | u8 otg_ctrl; |
88 | int type = POWER_SUPPLY_TYPE_USB_DCP; |
89 | |
90 | func_ctrl = isp1704_read(isp, ULPI_FUNC_CTRL); |
91 | otg_ctrl = isp1704_read(isp, ULPI_OTG_CTRL); |
92 | |
93 | /* disable pulldowns */ |
94 | reg = ULPI_OTG_CTRL_DM_PULLDOWN | ULPI_OTG_CTRL_DP_PULLDOWN; |
95 | isp1704_write(isp, ULPI_CLR(ULPI_OTG_CTRL), val: reg); |
96 | |
97 | /* full speed */ |
98 | isp1704_write(isp, ULPI_CLR(ULPI_FUNC_CTRL), |
99 | ULPI_FUNC_CTRL_XCVRSEL_MASK); |
100 | isp1704_write(isp, ULPI_SET(ULPI_FUNC_CTRL), |
101 | ULPI_FUNC_CTRL_FULL_SPEED); |
102 | |
103 | /* Enable strong pull-up on DP (1.5K) and reset */ |
104 | reg = ULPI_FUNC_CTRL_TERMSELECT | ULPI_FUNC_CTRL_RESET; |
105 | isp1704_write(isp, ULPI_SET(ULPI_FUNC_CTRL), val: reg); |
106 | usleep_range(min: 1000, max: 2000); |
107 | |
108 | reg = isp1704_read(isp, ULPI_DEBUG); |
109 | if ((reg & 3) != 3) |
110 | type = POWER_SUPPLY_TYPE_USB_CDP; |
111 | |
112 | /* recover original state */ |
113 | isp1704_write(isp, ULPI_FUNC_CTRL, val: func_ctrl); |
114 | isp1704_write(isp, ULPI_OTG_CTRL, val: otg_ctrl); |
115 | |
116 | return type; |
117 | } |
118 | |
119 | /* |
120 | * ISP1704 detects PS/2 adapters as charger. To make sure the detected charger |
121 | * is actually a dedicated charger, the following steps need to be taken. |
122 | */ |
123 | static inline int isp1704_charger_verify(struct isp1704_charger *isp) |
124 | { |
125 | int ret = 0; |
126 | u8 r; |
127 | |
128 | /* Reset the transceiver */ |
129 | r = isp1704_read(isp, ULPI_FUNC_CTRL); |
130 | r |= ULPI_FUNC_CTRL_RESET; |
131 | isp1704_write(isp, ULPI_FUNC_CTRL, val: r); |
132 | usleep_range(min: 1000, max: 2000); |
133 | |
134 | /* Set normal mode */ |
135 | r &= ~(ULPI_FUNC_CTRL_RESET | ULPI_FUNC_CTRL_OPMODE_MASK); |
136 | isp1704_write(isp, ULPI_FUNC_CTRL, val: r); |
137 | |
138 | /* Clear the DP and DM pull-down bits */ |
139 | r = ULPI_OTG_CTRL_DP_PULLDOWN | ULPI_OTG_CTRL_DM_PULLDOWN; |
140 | isp1704_write(isp, ULPI_CLR(ULPI_OTG_CTRL), val: r); |
141 | |
142 | /* Enable strong pull-up on DP (1.5K) and reset */ |
143 | r = ULPI_FUNC_CTRL_TERMSELECT | ULPI_FUNC_CTRL_RESET; |
144 | isp1704_write(isp, ULPI_SET(ULPI_FUNC_CTRL), val: r); |
145 | usleep_range(min: 1000, max: 2000); |
146 | |
147 | /* Read the line state */ |
148 | if (!isp1704_read(isp, ULPI_DEBUG)) { |
149 | /* Disable strong pull-up on DP (1.5K) */ |
150 | isp1704_write(isp, ULPI_CLR(ULPI_FUNC_CTRL), |
151 | ULPI_FUNC_CTRL_TERMSELECT); |
152 | return 1; |
153 | } |
154 | |
155 | /* Is it a charger or PS/2 connection */ |
156 | |
157 | /* Enable weak pull-up resistor on DP */ |
158 | isp1704_write(isp, ULPI_SET(ISP1704_PWR_CTRL), |
159 | ISP1704_PWR_CTRL_DP_WKPU_EN); |
160 | |
161 | /* Disable strong pull-up on DP (1.5K) */ |
162 | isp1704_write(isp, ULPI_CLR(ULPI_FUNC_CTRL), |
163 | ULPI_FUNC_CTRL_TERMSELECT); |
164 | |
165 | /* Enable weak pull-down resistor on DM */ |
166 | isp1704_write(isp, ULPI_SET(ULPI_OTG_CTRL), |
167 | ULPI_OTG_CTRL_DM_PULLDOWN); |
168 | |
169 | /* It's a charger if the line states are clear */ |
170 | if (!(isp1704_read(isp, ULPI_DEBUG))) |
171 | ret = 1; |
172 | |
173 | /* Disable weak pull-up resistor on DP */ |
174 | isp1704_write(isp, ULPI_CLR(ISP1704_PWR_CTRL), |
175 | ISP1704_PWR_CTRL_DP_WKPU_EN); |
176 | |
177 | return ret; |
178 | } |
179 | |
180 | static inline int isp1704_charger_detect(struct isp1704_charger *isp) |
181 | { |
182 | unsigned long timeout; |
183 | u8 pwr_ctrl; |
184 | int ret = 0; |
185 | |
186 | pwr_ctrl = isp1704_read(isp, ISP1704_PWR_CTRL); |
187 | |
188 | /* set SW control bit in PWR_CTRL register */ |
189 | isp1704_write(isp, ISP1704_PWR_CTRL, |
190 | ISP1704_PWR_CTRL_SWCTRL); |
191 | |
192 | /* enable manual charger detection */ |
193 | isp1704_write(isp, ULPI_SET(ISP1704_PWR_CTRL), |
194 | ISP1704_PWR_CTRL_SWCTRL |
195 | | ISP1704_PWR_CTRL_DPVSRC_EN); |
196 | usleep_range(min: 1000, max: 2000); |
197 | |
198 | timeout = jiffies + msecs_to_jiffies(m: 300); |
199 | do { |
200 | /* Check if there is a charger */ |
201 | if (isp1704_read(isp, ISP1704_PWR_CTRL) |
202 | & ISP1704_PWR_CTRL_VDAT_DET) { |
203 | ret = isp1704_charger_verify(isp); |
204 | break; |
205 | } |
206 | } while (!time_after(jiffies, timeout) && isp->online); |
207 | |
208 | /* recover original state */ |
209 | isp1704_write(isp, ISP1704_PWR_CTRL, val: pwr_ctrl); |
210 | |
211 | return ret; |
212 | } |
213 | |
214 | static inline int isp1704_charger_detect_dcp(struct isp1704_charger *isp) |
215 | { |
216 | if (isp1704_charger_detect(isp) && |
217 | isp1704_charger_type(isp) == POWER_SUPPLY_TYPE_USB_DCP) |
218 | return true; |
219 | else |
220 | return false; |
221 | } |
222 | |
223 | static void isp1704_charger_work(struct work_struct *data) |
224 | { |
225 | struct isp1704_charger *isp = |
226 | container_of(data, struct isp1704_charger, work); |
227 | static DEFINE_MUTEX(lock); |
228 | |
229 | mutex_lock(&lock); |
230 | |
231 | switch (isp->phy->last_event) { |
232 | case USB_EVENT_VBUS: |
233 | /* do not call wall charger detection more times */ |
234 | if (!isp->present) { |
235 | isp->online = true; |
236 | isp->present = 1; |
237 | isp1704_charger_set_power(isp, on: 1); |
238 | |
239 | /* detect wall charger */ |
240 | if (isp1704_charger_detect_dcp(isp)) { |
241 | isp->psy_desc.type = POWER_SUPPLY_TYPE_USB_DCP; |
242 | isp->current_max = 1800; |
243 | } else { |
244 | isp->psy_desc.type = POWER_SUPPLY_TYPE_USB; |
245 | isp->current_max = 500; |
246 | } |
247 | |
248 | /* enable data pullups */ |
249 | if (isp->phy->otg->gadget) |
250 | usb_gadget_connect(gadget: isp->phy->otg->gadget); |
251 | } |
252 | |
253 | if (isp->psy_desc.type != POWER_SUPPLY_TYPE_USB_DCP) { |
254 | /* |
255 | * Only 500mA here or high speed chirp |
256 | * handshaking may break |
257 | */ |
258 | if (isp->current_max > 500) |
259 | isp->current_max = 500; |
260 | |
261 | if (isp->current_max > 100) |
262 | isp->psy_desc.type = POWER_SUPPLY_TYPE_USB_CDP; |
263 | } |
264 | break; |
265 | case USB_EVENT_NONE: |
266 | isp->online = false; |
267 | isp->present = 0; |
268 | isp->current_max = 0; |
269 | isp->psy_desc.type = POWER_SUPPLY_TYPE_USB; |
270 | |
271 | /* |
272 | * Disable data pullups. We need to prevent the controller from |
273 | * enumerating. |
274 | * |
275 | * FIXME: This is here to allow charger detection with Host/HUB |
276 | * chargers. The pullups may be enabled elsewhere, so this can |
277 | * not be the final solution. |
278 | */ |
279 | if (isp->phy->otg->gadget) |
280 | usb_gadget_disconnect(gadget: isp->phy->otg->gadget); |
281 | |
282 | isp1704_charger_set_power(isp, on: 0); |
283 | break; |
284 | default: |
285 | goto out; |
286 | } |
287 | |
288 | power_supply_changed(psy: isp->psy); |
289 | out: |
290 | mutex_unlock(lock: &lock); |
291 | } |
292 | |
293 | static int isp1704_notifier_call(struct notifier_block *nb, |
294 | unsigned long val, void *v) |
295 | { |
296 | struct isp1704_charger *isp = |
297 | container_of(nb, struct isp1704_charger, nb); |
298 | |
299 | schedule_work(work: &isp->work); |
300 | |
301 | return NOTIFY_OK; |
302 | } |
303 | |
304 | static int isp1704_charger_get_property(struct power_supply *psy, |
305 | enum power_supply_property psp, |
306 | union power_supply_propval *val) |
307 | { |
308 | struct isp1704_charger *isp = power_supply_get_drvdata(psy); |
309 | |
310 | switch (psp) { |
311 | case POWER_SUPPLY_PROP_PRESENT: |
312 | val->intval = isp->present; |
313 | break; |
314 | case POWER_SUPPLY_PROP_ONLINE: |
315 | val->intval = isp->online; |
316 | break; |
317 | case POWER_SUPPLY_PROP_CURRENT_MAX: |
318 | val->intval = isp->current_max; |
319 | break; |
320 | case POWER_SUPPLY_PROP_MODEL_NAME: |
321 | val->strval = isp->model; |
322 | break; |
323 | case POWER_SUPPLY_PROP_MANUFACTURER: |
324 | val->strval = "NXP" ; |
325 | break; |
326 | default: |
327 | return -EINVAL; |
328 | } |
329 | return 0; |
330 | } |
331 | |
332 | static enum power_supply_property power_props[] = { |
333 | POWER_SUPPLY_PROP_PRESENT, |
334 | POWER_SUPPLY_PROP_ONLINE, |
335 | POWER_SUPPLY_PROP_CURRENT_MAX, |
336 | POWER_SUPPLY_PROP_MODEL_NAME, |
337 | POWER_SUPPLY_PROP_MANUFACTURER, |
338 | }; |
339 | |
340 | static inline int isp1704_test_ulpi(struct isp1704_charger *isp) |
341 | { |
342 | int vendor; |
343 | int product; |
344 | int i; |
345 | int ret; |
346 | |
347 | /* Test ULPI interface */ |
348 | ret = isp1704_write(isp, ULPI_SCRATCH, val: 0xaa); |
349 | if (ret < 0) |
350 | return ret; |
351 | |
352 | ret = isp1704_read(isp, ULPI_SCRATCH); |
353 | if (ret < 0) |
354 | return ret; |
355 | |
356 | if (ret != 0xaa) |
357 | return -ENODEV; |
358 | |
359 | /* Verify the product and vendor id matches */ |
360 | vendor = isp1704_read(isp, ULPI_VENDOR_ID_LOW); |
361 | vendor |= isp1704_read(isp, ULPI_VENDOR_ID_HIGH) << 8; |
362 | if (vendor != NXP_VENDOR_ID) |
363 | return -ENODEV; |
364 | |
365 | product = isp1704_read(isp, ULPI_PRODUCT_ID_LOW); |
366 | product |= isp1704_read(isp, ULPI_PRODUCT_ID_HIGH) << 8; |
367 | |
368 | for (i = 0; i < ARRAY_SIZE(isp170x_id); i++) { |
369 | if (product == isp170x_id[i]) { |
370 | sprintf(buf: isp->model, fmt: "isp%x" , product); |
371 | return product; |
372 | } |
373 | } |
374 | |
375 | dev_err(isp->dev, "product id %x not matching known ids" , product); |
376 | |
377 | return -ENODEV; |
378 | } |
379 | |
380 | static int isp1704_charger_probe(struct platform_device *pdev) |
381 | { |
382 | struct isp1704_charger *isp; |
383 | int ret = -ENODEV; |
384 | struct power_supply_config psy_cfg = {}; |
385 | |
386 | isp = devm_kzalloc(dev: &pdev->dev, size: sizeof(*isp), GFP_KERNEL); |
387 | if (!isp) |
388 | return -ENOMEM; |
389 | |
390 | isp->enable_gpio = devm_gpiod_get(dev: &pdev->dev, con_id: "nxp,enable" , |
391 | flags: GPIOD_OUT_HIGH); |
392 | if (IS_ERR(ptr: isp->enable_gpio)) { |
393 | ret = PTR_ERR(ptr: isp->enable_gpio); |
394 | dev_err(&pdev->dev, "Could not get reset gpio: %d\n" , ret); |
395 | return ret; |
396 | } |
397 | |
398 | if (pdev->dev.of_node) |
399 | isp->phy = devm_usb_get_phy_by_phandle(dev: &pdev->dev, phandle: "usb-phy" , index: 0); |
400 | else |
401 | isp->phy = devm_usb_get_phy(dev: &pdev->dev, type: USB_PHY_TYPE_USB2); |
402 | |
403 | if (IS_ERR(ptr: isp->phy)) { |
404 | ret = PTR_ERR(ptr: isp->phy); |
405 | dev_err(&pdev->dev, "usb_get_phy failed\n" ); |
406 | goto fail0; |
407 | } |
408 | |
409 | isp->dev = &pdev->dev; |
410 | platform_set_drvdata(pdev, data: isp); |
411 | |
412 | isp1704_charger_set_power(isp, on: 1); |
413 | |
414 | ret = isp1704_test_ulpi(isp); |
415 | if (ret < 0) { |
416 | dev_err(&pdev->dev, "isp1704_test_ulpi failed\n" ); |
417 | goto fail1; |
418 | } |
419 | |
420 | isp->psy_desc.name = "isp1704" ; |
421 | isp->psy_desc.type = POWER_SUPPLY_TYPE_USB; |
422 | isp->psy_desc.properties = power_props; |
423 | isp->psy_desc.num_properties = ARRAY_SIZE(power_props); |
424 | isp->psy_desc.get_property = isp1704_charger_get_property; |
425 | |
426 | psy_cfg.drv_data = isp; |
427 | |
428 | isp->psy = power_supply_register(parent: isp->dev, desc: &isp->psy_desc, cfg: &psy_cfg); |
429 | if (IS_ERR(ptr: isp->psy)) { |
430 | ret = PTR_ERR(ptr: isp->psy); |
431 | dev_err(&pdev->dev, "power_supply_register failed\n" ); |
432 | goto fail1; |
433 | } |
434 | |
435 | /* |
436 | * REVISIT: using work in order to allow the usb notifications to be |
437 | * made atomically in the future. |
438 | */ |
439 | INIT_WORK(&isp->work, isp1704_charger_work); |
440 | |
441 | isp->nb.notifier_call = isp1704_notifier_call; |
442 | |
443 | ret = usb_register_notifier(x: isp->phy, nb: &isp->nb); |
444 | if (ret) { |
445 | dev_err(&pdev->dev, "usb_register_notifier failed\n" ); |
446 | goto fail2; |
447 | } |
448 | |
449 | dev_info(isp->dev, "registered with product id %s\n" , isp->model); |
450 | |
451 | /* |
452 | * Taking over the D+ pullup. |
453 | * |
454 | * FIXME: The device will be disconnected if it was already |
455 | * enumerated. The charger driver should be always loaded before any |
456 | * gadget is loaded. |
457 | */ |
458 | if (isp->phy->otg->gadget) |
459 | usb_gadget_disconnect(gadget: isp->phy->otg->gadget); |
460 | |
461 | if (isp->phy->last_event == USB_EVENT_NONE) |
462 | isp1704_charger_set_power(isp, on: 0); |
463 | |
464 | /* Detect charger if VBUS is valid (the cable was already plugged). */ |
465 | if (isp->phy->last_event == USB_EVENT_VBUS && |
466 | !isp->phy->otg->default_a) |
467 | schedule_work(work: &isp->work); |
468 | |
469 | return 0; |
470 | fail2: |
471 | power_supply_unregister(psy: isp->psy); |
472 | fail1: |
473 | isp1704_charger_set_power(isp, on: 0); |
474 | fail0: |
475 | dev_err(&pdev->dev, "failed to register isp1704 with error %d\n" , ret); |
476 | |
477 | return ret; |
478 | } |
479 | |
480 | static void isp1704_charger_remove(struct platform_device *pdev) |
481 | { |
482 | struct isp1704_charger *isp = platform_get_drvdata(pdev); |
483 | |
484 | usb_unregister_notifier(x: isp->phy, nb: &isp->nb); |
485 | power_supply_unregister(psy: isp->psy); |
486 | isp1704_charger_set_power(isp, on: 0); |
487 | } |
488 | |
489 | #ifdef CONFIG_OF |
490 | static const struct of_device_id omap_isp1704_of_match[] = { |
491 | { .compatible = "nxp,isp1704" , }, |
492 | { .compatible = "nxp,isp1707" , }, |
493 | {}, |
494 | }; |
495 | MODULE_DEVICE_TABLE(of, omap_isp1704_of_match); |
496 | #endif |
497 | |
498 | static struct platform_driver isp1704_charger_driver = { |
499 | .driver = { |
500 | .name = "isp1704_charger" , |
501 | .of_match_table = of_match_ptr(omap_isp1704_of_match), |
502 | }, |
503 | .probe = isp1704_charger_probe, |
504 | .remove_new = isp1704_charger_remove, |
505 | }; |
506 | |
507 | module_platform_driver(isp1704_charger_driver); |
508 | |
509 | MODULE_ALIAS("platform:isp1704_charger" ); |
510 | MODULE_AUTHOR("Nokia Corporation" ); |
511 | MODULE_DESCRIPTION("ISP170x USB Charger driver" ); |
512 | MODULE_LICENSE("GPL" ); |
513 | |