1// SPDX-License-Identifier: GPL-2.0-only
2/**
3 * extcon-qcom-spmi-misc.c - Qualcomm USB extcon driver to support USB ID
4 *				detection based on extcon-usb-gpio.c.
5 *
6 * Copyright (C) 2016 Linaro, Ltd.
7 * Stephen Boyd <stephen.boyd@linaro.org>
8 */
9
10#include <linux/extcon-provider.h>
11#include <linux/init.h>
12#include <linux/interrupt.h>
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/mod_devicetable.h>
16#include <linux/platform_device.h>
17#include <linux/slab.h>
18#include <linux/workqueue.h>
19
20#define USB_ID_DEBOUNCE_MS	5	/* ms */
21
22struct qcom_usb_extcon_info {
23	struct extcon_dev *edev;
24	int irq;
25	struct delayed_work wq_detcable;
26	unsigned long debounce_jiffies;
27};
28
29static const unsigned int qcom_usb_extcon_cable[] = {
30	EXTCON_USB_HOST,
31	EXTCON_NONE,
32};
33
34static void qcom_usb_extcon_detect_cable(struct work_struct *work)
35{
36	bool id;
37	int ret;
38	struct qcom_usb_extcon_info *info = container_of(to_delayed_work(work),
39						    struct qcom_usb_extcon_info,
40						    wq_detcable);
41
42	/* check ID and update cable state */
43	ret = irq_get_irqchip_state(info->irq, IRQCHIP_STATE_LINE_LEVEL, &id);
44	if (ret)
45		return;
46
47	extcon_set_state_sync(info->edev, EXTCON_USB_HOST, !id);
48}
49
50static irqreturn_t qcom_usb_irq_handler(int irq, void *dev_id)
51{
52	struct qcom_usb_extcon_info *info = dev_id;
53
54	queue_delayed_work(system_power_efficient_wq, &info->wq_detcable,
55			   info->debounce_jiffies);
56
57	return IRQ_HANDLED;
58}
59
60static int qcom_usb_extcon_probe(struct platform_device *pdev)
61{
62	struct device *dev = &pdev->dev;
63	struct qcom_usb_extcon_info *info;
64	int ret;
65
66	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
67	if (!info)
68		return -ENOMEM;
69
70	info->edev = devm_extcon_dev_allocate(dev, qcom_usb_extcon_cable);
71	if (IS_ERR(info->edev)) {
72		dev_err(dev, "failed to allocate extcon device\n");
73		return -ENOMEM;
74	}
75
76	ret = devm_extcon_dev_register(dev, info->edev);
77	if (ret < 0) {
78		dev_err(dev, "failed to register extcon device\n");
79		return ret;
80	}
81
82	info->debounce_jiffies = msecs_to_jiffies(USB_ID_DEBOUNCE_MS);
83	INIT_DELAYED_WORK(&info->wq_detcable, qcom_usb_extcon_detect_cable);
84
85	info->irq = platform_get_irq_byname(pdev, "usb_id");
86	if (info->irq < 0)
87		return info->irq;
88
89	ret = devm_request_threaded_irq(dev, info->irq, NULL,
90					qcom_usb_irq_handler,
91					IRQF_TRIGGER_RISING |
92					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
93					pdev->name, info);
94	if (ret < 0) {
95		dev_err(dev, "failed to request handler for ID IRQ\n");
96		return ret;
97	}
98
99	platform_set_drvdata(pdev, info);
100	device_init_wakeup(dev, 1);
101
102	/* Perform initial detection */
103	qcom_usb_extcon_detect_cable(&info->wq_detcable.work);
104
105	return 0;
106}
107
108static int qcom_usb_extcon_remove(struct platform_device *pdev)
109{
110	struct qcom_usb_extcon_info *info = platform_get_drvdata(pdev);
111
112	cancel_delayed_work_sync(&info->wq_detcable);
113
114	return 0;
115}
116
117#ifdef CONFIG_PM_SLEEP
118static int qcom_usb_extcon_suspend(struct device *dev)
119{
120	struct qcom_usb_extcon_info *info = dev_get_drvdata(dev);
121	int ret = 0;
122
123	if (device_may_wakeup(dev))
124		ret = enable_irq_wake(info->irq);
125
126	return ret;
127}
128
129static int qcom_usb_extcon_resume(struct device *dev)
130{
131	struct qcom_usb_extcon_info *info = dev_get_drvdata(dev);
132	int ret = 0;
133
134	if (device_may_wakeup(dev))
135		ret = disable_irq_wake(info->irq);
136
137	return ret;
138}
139#endif
140
141static SIMPLE_DEV_PM_OPS(qcom_usb_extcon_pm_ops,
142			 qcom_usb_extcon_suspend, qcom_usb_extcon_resume);
143
144static const struct of_device_id qcom_usb_extcon_dt_match[] = {
145	{ .compatible = "qcom,pm8941-misc", },
146	{ }
147};
148MODULE_DEVICE_TABLE(of, qcom_usb_extcon_dt_match);
149
150static struct platform_driver qcom_usb_extcon_driver = {
151	.probe		= qcom_usb_extcon_probe,
152	.remove		= qcom_usb_extcon_remove,
153	.driver		= {
154		.name	= "extcon-pm8941-misc",
155		.pm	= &qcom_usb_extcon_pm_ops,
156		.of_match_table = qcom_usb_extcon_dt_match,
157	},
158};
159module_platform_driver(qcom_usb_extcon_driver);
160
161MODULE_DESCRIPTION("QCOM USB ID extcon driver");
162MODULE_AUTHOR("Stephen Boyd <stephen.boyd@linaro.org>");
163MODULE_LICENSE("GPL v2");
164