1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * extcon-axp288.c - X-Power AXP288 PMIC extcon cable detection driver
4 *
5 * Copyright (c) 2017-2018 Hans de Goede <hdegoede@redhat.com>
6 * Copyright (C) 2015 Intel Corporation
7 * Author: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
8 */
9
10 #include <linux/acpi.h>
11 #include <linux/module.h>
12 #include <linux/kernel.h>
13 #include <linux/io.h>
14 #include <linux/slab.h>
15 #include <linux/interrupt.h>
16 #include <linux/platform_device.h>
17 #include <linux/property.h>
18 #include <linux/notifier.h>
19 #include <linux/extcon-provider.h>
20 #include <linux/regmap.h>
21 #include <linux/mfd/axp20x.h>
22 #include <linux/usb/role.h>
23 #include <linux/workqueue.h>
24
25 #include <asm/cpu_device_id.h>
26 #include <asm/intel-family.h>
27 #include <asm/iosf_mbi.h>
28
29 /* Power source status register */
30 #define PS_STAT_VBUS_TRIGGER BIT(0)
31 #define PS_STAT_BAT_CHRG_DIR BIT(2)
32 #define PS_STAT_VBUS_ABOVE_VHOLD BIT(3)
33 #define PS_STAT_VBUS_VALID BIT(4)
34 #define PS_STAT_VBUS_PRESENT BIT(5)
35
36 /* BC module global register */
37 #define BC_GLOBAL_RUN BIT(0)
38 #define BC_GLOBAL_DET_STAT BIT(2)
39 #define BC_GLOBAL_DBP_TOUT BIT(3)
40 #define BC_GLOBAL_VLGC_COM_SEL BIT(4)
41 #define BC_GLOBAL_DCD_TOUT_MASK (BIT(6)|BIT(5))
42 #define BC_GLOBAL_DCD_TOUT_300MS 0
43 #define BC_GLOBAL_DCD_TOUT_100MS 1
44 #define BC_GLOBAL_DCD_TOUT_500MS 2
45 #define BC_GLOBAL_DCD_TOUT_900MS 3
46 #define BC_GLOBAL_DCD_DET_SEL BIT(7)
47
48 /* BC module vbus control and status register */
49 #define VBUS_CNTL_DPDM_PD_EN BIT(4)
50 #define VBUS_CNTL_DPDM_FD_EN BIT(5)
51 #define VBUS_CNTL_FIRST_PO_STAT BIT(6)
52
53 /* BC USB status register */
54 #define USB_STAT_BUS_STAT_MASK (BIT(3)|BIT(2)|BIT(1)|BIT(0))
55 #define USB_STAT_BUS_STAT_SHIFT 0
56 #define USB_STAT_BUS_STAT_ATHD 0
57 #define USB_STAT_BUS_STAT_CONN 1
58 #define USB_STAT_BUS_STAT_SUSP 2
59 #define USB_STAT_BUS_STAT_CONF 3
60 #define USB_STAT_USB_SS_MODE BIT(4)
61 #define USB_STAT_DEAD_BAT_DET BIT(6)
62 #define USB_STAT_DBP_UNCFG BIT(7)
63
64 /* BC detect status register */
65 #define DET_STAT_MASK (BIT(7)|BIT(6)|BIT(5))
66 #define DET_STAT_SHIFT 5
67 #define DET_STAT_SDP 1
68 #define DET_STAT_CDP 2
69 #define DET_STAT_DCP 3
70
71 enum axp288_extcon_reg {
72 AXP288_PS_STAT_REG = 0x00,
73 AXP288_PS_BOOT_REASON_REG = 0x02,
74 AXP288_BC_GLOBAL_REG = 0x2c,
75 AXP288_BC_VBUS_CNTL_REG = 0x2d,
76 AXP288_BC_USB_STAT_REG = 0x2e,
77 AXP288_BC_DET_STAT_REG = 0x2f,
78 };
79
80 enum axp288_extcon_irq {
81 VBUS_FALLING_IRQ = 0,
82 VBUS_RISING_IRQ,
83 MV_CHNG_IRQ,
84 BC_USB_CHNG_IRQ,
85 EXTCON_IRQ_END,
86 };
87
88 static const unsigned int axp288_extcon_cables[] = {
89 EXTCON_CHG_USB_SDP,
90 EXTCON_CHG_USB_CDP,
91 EXTCON_CHG_USB_DCP,
92 EXTCON_USB,
93 EXTCON_NONE,
94 };
95
96 struct axp288_extcon_info {
97 struct device *dev;
98 struct regmap *regmap;
99 struct regmap_irq_chip_data *regmap_irqc;
100 struct usb_role_switch *role_sw;
101 struct work_struct role_work;
102 int irq[EXTCON_IRQ_END];
103 struct extcon_dev *edev;
104 struct extcon_dev *id_extcon;
105 struct notifier_block id_nb;
106 unsigned int previous_cable;
107 bool vbus_attach;
108 };
109
110 static const struct x86_cpu_id cherry_trail_cpu_ids[] = {
111 X86_MATCH_VFM(INTEL_ATOM_AIRMONT, NULL),
112 {}
113 };
114
115 /* Power up/down reason string array */
116 static const char * const axp288_pwr_up_down_info[] = {
117 "Last wake caused by user pressing the power button",
118 "Last wake caused by a charger insertion",
119 "Last wake caused by a battery insertion",
120 "Last wake caused by SOC initiated global reset",
121 "Last wake caused by cold reset",
122 "Last shutdown caused by PMIC UVLO threshold",
123 "Last shutdown caused by SOC initiated cold off",
124 "Last shutdown caused by user pressing the power button",
125 };
126
127 /*
128 * Decode and log the given "reset source indicator" (rsi)
129 * register and then clear it.
130 */
axp288_extcon_log_rsi(struct axp288_extcon_info * info)131 static void axp288_extcon_log_rsi(struct axp288_extcon_info *info)
132 {
133 unsigned int val, i, clear_mask = 0;
134 unsigned long bits;
135 int ret;
136
137 ret = regmap_read(info->regmap, AXP288_PS_BOOT_REASON_REG, &val);
138 if (ret < 0) {
139 dev_err(info->dev, "failed to read reset source indicator\n");
140 return;
141 }
142
143 bits = val & GENMASK(ARRAY_SIZE(axp288_pwr_up_down_info) - 1, 0);
144 for_each_set_bit(i, &bits, ARRAY_SIZE(axp288_pwr_up_down_info))
145 dev_dbg(info->dev, "%s\n", axp288_pwr_up_down_info[i]);
146 clear_mask = bits;
147
148 /* Clear the register value for next reboot (write 1 to clear bit) */
149 regmap_write(info->regmap, AXP288_PS_BOOT_REASON_REG, clear_mask);
150 }
151
152 /*
153 * The below code to control the USB role-switch on devices with an AXP288
154 * may seem out of place, but there are 2 reasons why this is the best place
155 * to control the USB role-switch on such devices:
156 * 1) On many devices the USB role is controlled by AML code, but the AML code
157 * only switches between the host and none roles, because of Windows not
158 * really using device mode. To make device mode work we need to toggle
159 * between the none/device roles based on Vbus presence, and this driver
160 * gets interrupts on Vbus insertion / removal.
161 * 2) In order for our BC1.2 charger detection to work properly the role
162 * mux must be properly set to device mode before we do the detection.
163 */
164
165 /* Returns the id-pin value, note pulled low / false == host-mode */
axp288_get_id_pin(struct axp288_extcon_info * info)166 static bool axp288_get_id_pin(struct axp288_extcon_info *info)
167 {
168 enum usb_role role;
169
170 if (info->id_extcon)
171 return extcon_get_state(info->id_extcon, EXTCON_USB_HOST) <= 0;
172
173 /* We cannot access the id-pin, see what mode the AML code has set */
174 role = usb_role_switch_get_role(info->role_sw);
175 return role != USB_ROLE_HOST;
176 }
177
axp288_usb_role_work(struct work_struct * work)178 static void axp288_usb_role_work(struct work_struct *work)
179 {
180 struct axp288_extcon_info *info =
181 container_of(work, struct axp288_extcon_info, role_work);
182 enum usb_role role;
183 bool id_pin;
184 int ret;
185
186 id_pin = axp288_get_id_pin(info);
187 if (!id_pin)
188 role = USB_ROLE_HOST;
189 else if (info->vbus_attach)
190 role = USB_ROLE_DEVICE;
191 else
192 role = USB_ROLE_NONE;
193
194 ret = usb_role_switch_set_role(info->role_sw, role);
195 if (ret)
196 dev_err(info->dev, "failed to set role: %d\n", ret);
197 }
198
axp288_get_vbus_attach(struct axp288_extcon_info * info)199 static bool axp288_get_vbus_attach(struct axp288_extcon_info *info)
200 {
201 int ret, pwr_stat;
202
203 ret = regmap_read(info->regmap, AXP288_PS_STAT_REG, &pwr_stat);
204 if (ret < 0) {
205 dev_err(info->dev, "failed to read vbus status\n");
206 return false;
207 }
208
209 return !!(pwr_stat & PS_STAT_VBUS_VALID);
210 }
211
axp288_handle_chrg_det_event(struct axp288_extcon_info * info)212 static int axp288_handle_chrg_det_event(struct axp288_extcon_info *info)
213 {
214 int ret, stat, cfg;
215 u8 chrg_type;
216 unsigned int cable = info->previous_cable;
217 bool vbus_attach = false;
218
219 ret = iosf_mbi_block_punit_i2c_access();
220 if (ret < 0)
221 return ret;
222
223 vbus_attach = axp288_get_vbus_attach(info);
224 if (!vbus_attach)
225 goto no_vbus;
226
227 /* Check charger detection completion status */
228 ret = regmap_read(info->regmap, AXP288_BC_GLOBAL_REG, &cfg);
229 if (ret < 0)
230 goto dev_det_ret;
231 if (cfg & BC_GLOBAL_DET_STAT) {
232 dev_dbg(info->dev, "can't complete the charger detection\n");
233 goto dev_det_ret;
234 }
235
236 ret = regmap_read(info->regmap, AXP288_BC_DET_STAT_REG, &stat);
237 if (ret < 0)
238 goto dev_det_ret;
239
240 chrg_type = (stat & DET_STAT_MASK) >> DET_STAT_SHIFT;
241
242 switch (chrg_type) {
243 case DET_STAT_SDP:
244 dev_dbg(info->dev, "sdp cable is connected\n");
245 cable = EXTCON_CHG_USB_SDP;
246 break;
247 case DET_STAT_CDP:
248 dev_dbg(info->dev, "cdp cable is connected\n");
249 cable = EXTCON_CHG_USB_CDP;
250 break;
251 case DET_STAT_DCP:
252 dev_dbg(info->dev, "dcp cable is connected\n");
253 cable = EXTCON_CHG_USB_DCP;
254 break;
255 default:
256 dev_warn(info->dev, "unknown (reserved) bc detect result\n");
257 cable = EXTCON_CHG_USB_SDP;
258 }
259
260 no_vbus:
261 iosf_mbi_unblock_punit_i2c_access();
262
263 extcon_set_state_sync(info->edev, info->previous_cable, false);
264 if (info->previous_cable == EXTCON_CHG_USB_SDP)
265 extcon_set_state_sync(info->edev, EXTCON_USB, false);
266
267 if (vbus_attach) {
268 extcon_set_state_sync(info->edev, cable, vbus_attach);
269 if (cable == EXTCON_CHG_USB_SDP)
270 extcon_set_state_sync(info->edev, EXTCON_USB,
271 vbus_attach);
272
273 info->previous_cable = cable;
274 }
275
276 if (info->role_sw && info->vbus_attach != vbus_attach) {
277 info->vbus_attach = vbus_attach;
278 /* Setting the role can take a while */
279 queue_work(system_long_wq, &info->role_work);
280 }
281
282 return 0;
283
284 dev_det_ret:
285 iosf_mbi_unblock_punit_i2c_access();
286
287 if (ret < 0)
288 dev_err(info->dev, "failed to detect BC Mod\n");
289
290 return ret;
291 }
292
axp288_extcon_id_evt(struct notifier_block * nb,unsigned long event,void * param)293 static int axp288_extcon_id_evt(struct notifier_block *nb,
294 unsigned long event, void *param)
295 {
296 struct axp288_extcon_info *info =
297 container_of(nb, struct axp288_extcon_info, id_nb);
298
299 /* We may not sleep and setting the role can take a while */
300 queue_work(system_long_wq, &info->role_work);
301
302 return NOTIFY_OK;
303 }
304
axp288_extcon_isr(int irq,void * data)305 static irqreturn_t axp288_extcon_isr(int irq, void *data)
306 {
307 struct axp288_extcon_info *info = data;
308 int ret;
309
310 ret = axp288_handle_chrg_det_event(info);
311 if (ret < 0)
312 dev_err(info->dev, "failed to handle the interrupt\n");
313
314 return IRQ_HANDLED;
315 }
316
axp288_extcon_enable(struct axp288_extcon_info * info)317 static int axp288_extcon_enable(struct axp288_extcon_info *info)
318 {
319 int ret = 0;
320
321 ret = iosf_mbi_block_punit_i2c_access();
322 if (ret < 0)
323 return ret;
324
325 regmap_update_bits(info->regmap, AXP288_BC_GLOBAL_REG,
326 BC_GLOBAL_RUN, 0);
327 /* Enable the charger detection logic */
328 regmap_update_bits(info->regmap, AXP288_BC_GLOBAL_REG,
329 BC_GLOBAL_RUN, BC_GLOBAL_RUN);
330
331 iosf_mbi_unblock_punit_i2c_access();
332
333 return ret;
334 }
335
axp288_put_role_sw(void * data)336 static void axp288_put_role_sw(void *data)
337 {
338 struct axp288_extcon_info *info = data;
339
340 cancel_work_sync(&info->role_work);
341 usb_role_switch_put(info->role_sw);
342 }
343
axp288_extcon_find_role_sw(struct axp288_extcon_info * info)344 static int axp288_extcon_find_role_sw(struct axp288_extcon_info *info)
345 {
346 const struct software_node *swnode;
347 struct fwnode_handle *fwnode;
348
349 if (!x86_match_cpu(cherry_trail_cpu_ids))
350 return 0;
351
352 swnode = software_node_find_by_name(NULL, "intel-xhci-usb-sw");
353 if (!swnode)
354 return -EPROBE_DEFER;
355
356 fwnode = software_node_fwnode(swnode);
357 info->role_sw = usb_role_switch_find_by_fwnode(fwnode);
358 fwnode_handle_put(fwnode);
359
360 return info->role_sw ? 0 : -EPROBE_DEFER;
361 }
362
axp288_extcon_probe(struct platform_device * pdev)363 static int axp288_extcon_probe(struct platform_device *pdev)
364 {
365 struct axp288_extcon_info *info;
366 struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
367 struct device *dev = &pdev->dev;
368 struct acpi_device *adev;
369 int ret, i, pirq;
370
371 info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
372 if (!info)
373 return -ENOMEM;
374
375 info->dev = &pdev->dev;
376 info->regmap = axp20x->regmap;
377 info->regmap_irqc = axp20x->regmap_irqc;
378 info->previous_cable = EXTCON_NONE;
379 INIT_WORK(&info->role_work, axp288_usb_role_work);
380 info->id_nb.notifier_call = axp288_extcon_id_evt;
381
382 platform_set_drvdata(pdev, info);
383
384 ret = axp288_extcon_find_role_sw(info);
385 if (ret)
386 return ret;
387
388 if (info->role_sw) {
389 ret = devm_add_action_or_reset(dev, axp288_put_role_sw, info);
390 if (ret)
391 return ret;
392
393 adev = acpi_dev_get_first_match_dev("INT3496", NULL, -1);
394 if (adev) {
395 info->id_extcon = extcon_get_extcon_dev(acpi_dev_name(adev));
396 acpi_dev_put(adev);
397 if (IS_ERR(info->id_extcon))
398 return PTR_ERR(info->id_extcon);
399
400 dev_info(dev, "controlling USB role\n");
401 } else {
402 dev_info(dev, "controlling USB role based on Vbus presence\n");
403 }
404 }
405
406 ret = iosf_mbi_block_punit_i2c_access();
407 if (ret < 0)
408 return ret;
409
410 info->vbus_attach = axp288_get_vbus_attach(info);
411
412 axp288_extcon_log_rsi(info);
413
414 iosf_mbi_unblock_punit_i2c_access();
415
416 /* Initialize extcon device */
417 info->edev = devm_extcon_dev_allocate(&pdev->dev,
418 axp288_extcon_cables);
419 if (IS_ERR(info->edev)) {
420 dev_err(&pdev->dev, "failed to allocate memory for extcon\n");
421 return PTR_ERR(info->edev);
422 }
423
424 /* Register extcon device */
425 ret = devm_extcon_dev_register(&pdev->dev, info->edev);
426 if (ret) {
427 dev_err(&pdev->dev, "failed to register extcon device\n");
428 return ret;
429 }
430
431 for (i = 0; i < EXTCON_IRQ_END; i++) {
432 pirq = platform_get_irq(pdev, i);
433 if (pirq < 0)
434 return pirq;
435
436 info->irq[i] = regmap_irq_get_virq(info->regmap_irqc, pirq);
437 if (info->irq[i] < 0) {
438 dev_err(&pdev->dev,
439 "failed to get virtual interrupt=%d\n", pirq);
440 ret = info->irq[i];
441 return ret;
442 }
443
444 ret = devm_request_threaded_irq(&pdev->dev, info->irq[i],
445 NULL, axp288_extcon_isr,
446 IRQF_ONESHOT | IRQF_NO_SUSPEND,
447 pdev->name, info);
448 if (ret) {
449 dev_err(&pdev->dev, "failed to request interrupt=%d\n",
450 info->irq[i]);
451 return ret;
452 }
453 }
454
455 if (info->id_extcon) {
456 ret = devm_extcon_register_notifier_all(dev, info->id_extcon,
457 &info->id_nb);
458 if (ret)
459 return ret;
460 }
461
462 /* Make sure the role-sw is set correctly before doing BC detection */
463 if (info->role_sw) {
464 queue_work(system_long_wq, &info->role_work);
465 flush_work(&info->role_work);
466 }
467
468 /* Start charger cable type detection */
469 ret = axp288_extcon_enable(info);
470 if (ret < 0)
471 return ret;
472
473 device_init_wakeup(dev, true);
474 platform_set_drvdata(pdev, info);
475
476 return 0;
477 }
478
axp288_extcon_suspend(struct device * dev)479 static int __maybe_unused axp288_extcon_suspend(struct device *dev)
480 {
481 struct axp288_extcon_info *info = dev_get_drvdata(dev);
482
483 if (device_may_wakeup(dev))
484 enable_irq_wake(info->irq[VBUS_RISING_IRQ]);
485
486 return 0;
487 }
488
axp288_extcon_resume(struct device * dev)489 static int __maybe_unused axp288_extcon_resume(struct device *dev)
490 {
491 struct axp288_extcon_info *info = dev_get_drvdata(dev);
492
493 /*
494 * Wakeup when a charger is connected to do charger-type
495 * connection and generate an extcon event which makes the
496 * axp288 charger driver set the input current limit.
497 */
498 if (device_may_wakeup(dev))
499 disable_irq_wake(info->irq[VBUS_RISING_IRQ]);
500
501 return 0;
502 }
503
504 static SIMPLE_DEV_PM_OPS(axp288_extcon_pm_ops, axp288_extcon_suspend,
505 axp288_extcon_resume);
506
507 static const struct platform_device_id axp288_extcon_table[] = {
508 { .name = "axp288_extcon" },
509 {},
510 };
511 MODULE_DEVICE_TABLE(platform, axp288_extcon_table);
512
513 static struct platform_driver axp288_extcon_driver = {
514 .probe = axp288_extcon_probe,
515 .id_table = axp288_extcon_table,
516 .driver = {
517 .name = "axp288_extcon",
518 .pm = &axp288_extcon_pm_ops,
519 },
520 };
521 module_platform_driver(axp288_extcon_driver);
522
523 MODULE_AUTHOR("Ramakrishna Pallala <ramakrishna.pallala@intel.com>");
524 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
525 MODULE_DESCRIPTION("X-Powers AXP288 extcon driver");
526 MODULE_LICENSE("GPL v2");
527