1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Intel INT3496 ACPI device extcon driver
4 *
5 * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
6 *
7 * Based on android x86 kernel code which is:
8 *
9 * Copyright (c) 2014, Intel Corporation.
10 * Author: David Cohen <david.a.cohen@linux.intel.com>
11 */
12
13 #include <linux/acpi.h>
14 #include <linux/extcon-provider.h>
15 #include <linux/gpio/consumer.h>
16 #include <linux/interrupt.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19
20 #define INT3496_GPIO_USB_ID 0
21 #define INT3496_GPIO_VBUS_EN 1
22 #define INT3496_GPIO_USB_MUX 2
23 #define DEBOUNCE_TIME msecs_to_jiffies(50)
24
25 struct int3496_data {
26 struct device *dev;
27 struct extcon_dev *edev;
28 struct delayed_work work;
29 struct gpio_desc *gpio_usb_id;
30 struct gpio_desc *gpio_vbus_en;
31 struct gpio_desc *gpio_usb_mux;
32 int usb_id_irq;
33 };
34
35 static const unsigned int int3496_cable[] = {
36 EXTCON_USB_HOST,
37 EXTCON_NONE,
38 };
39
40 static const struct acpi_gpio_params id_gpios = { INT3496_GPIO_USB_ID, 0, false };
41 static const struct acpi_gpio_params vbus_gpios = { INT3496_GPIO_VBUS_EN, 0, false };
42 static const struct acpi_gpio_params mux_gpios = { INT3496_GPIO_USB_MUX, 0, false };
43
44 static const struct acpi_gpio_mapping acpi_int3496_default_gpios[] = {
45 /*
46 * Some platforms have a bug in ACPI GPIO description making IRQ
47 * GPIO to be output only. Ask the GPIO core to ignore this limit.
48 */
49 { "id-gpios", &id_gpios, 1, ACPI_GPIO_QUIRK_NO_IO_RESTRICTION },
50 { "vbus-gpios", &vbus_gpios, 1 },
51 { "mux-gpios", &mux_gpios, 1 },
52 { },
53 };
54
int3496_do_usb_id(struct work_struct * work)55 static void int3496_do_usb_id(struct work_struct *work)
56 {
57 struct int3496_data *data =
58 container_of(work, struct int3496_data, work.work);
59 int id = gpiod_get_value_cansleep(data->gpio_usb_id);
60
61 /* id == 1: PERIPHERAL, id == 0: HOST */
62 dev_dbg(data->dev, "Connected %s cable\n", id ? "PERIPHERAL" : "HOST");
63
64 /*
65 * Peripheral: set USB mux to peripheral and disable VBUS
66 * Host: set USB mux to host and enable VBUS
67 */
68 if (!IS_ERR(data->gpio_usb_mux))
69 gpiod_direction_output(data->gpio_usb_mux, id);
70
71 if (!IS_ERR(data->gpio_vbus_en))
72 gpiod_direction_output(data->gpio_vbus_en, !id);
73
74 extcon_set_state_sync(data->edev, EXTCON_USB_HOST, !id);
75 }
76
int3496_thread_isr(int irq,void * priv)77 static irqreturn_t int3496_thread_isr(int irq, void *priv)
78 {
79 struct int3496_data *data = priv;
80
81 /* Let the pin settle before processing it */
82 mod_delayed_work(system_wq, &data->work, DEBOUNCE_TIME);
83
84 return IRQ_HANDLED;
85 }
86
int3496_probe(struct platform_device * pdev)87 static int int3496_probe(struct platform_device *pdev)
88 {
89 struct device *dev = &pdev->dev;
90 struct int3496_data *data;
91 int ret;
92
93 ret = devm_acpi_dev_add_driver_gpios(dev, acpi_int3496_default_gpios);
94 if (ret) {
95 dev_err(dev, "can't add GPIO ACPI mapping\n");
96 return ret;
97 }
98
99 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
100 if (!data)
101 return -ENOMEM;
102
103 data->dev = dev;
104 INIT_DELAYED_WORK(&data->work, int3496_do_usb_id);
105
106 data->gpio_usb_id = devm_gpiod_get(dev, "id", GPIOD_IN);
107 if (IS_ERR(data->gpio_usb_id)) {
108 ret = PTR_ERR(data->gpio_usb_id);
109 dev_err(dev, "can't request USB ID GPIO: %d\n", ret);
110 return ret;
111 }
112
113 data->usb_id_irq = gpiod_to_irq(data->gpio_usb_id);
114 if (data->usb_id_irq < 0) {
115 dev_err(dev, "can't get USB ID IRQ: %d\n", data->usb_id_irq);
116 return data->usb_id_irq;
117 }
118
119 data->gpio_vbus_en = devm_gpiod_get(dev, "vbus", GPIOD_ASIS);
120 if (IS_ERR(data->gpio_vbus_en))
121 dev_info(dev, "can't request VBUS EN GPIO\n");
122
123 data->gpio_usb_mux = devm_gpiod_get(dev, "mux", GPIOD_ASIS);
124 if (IS_ERR(data->gpio_usb_mux))
125 dev_info(dev, "can't request USB MUX GPIO\n");
126
127 /* register extcon device */
128 data->edev = devm_extcon_dev_allocate(dev, int3496_cable);
129 if (IS_ERR(data->edev))
130 return -ENOMEM;
131
132 ret = devm_extcon_dev_register(dev, data->edev);
133 if (ret < 0) {
134 dev_err(dev, "can't register extcon device: %d\n", ret);
135 return ret;
136 }
137
138 ret = devm_request_threaded_irq(dev, data->usb_id_irq,
139 NULL, int3496_thread_isr,
140 IRQF_SHARED | IRQF_ONESHOT |
141 IRQF_TRIGGER_RISING |
142 IRQF_TRIGGER_FALLING,
143 dev_name(dev), data);
144 if (ret < 0) {
145 dev_err(dev, "can't request IRQ for USB ID GPIO: %d\n", ret);
146 return ret;
147 }
148
149 /* process id-pin so that we start with the right status */
150 queue_delayed_work(system_wq, &data->work, 0);
151 flush_delayed_work(&data->work);
152
153 platform_set_drvdata(pdev, data);
154
155 return 0;
156 }
157
int3496_remove(struct platform_device * pdev)158 static int int3496_remove(struct platform_device *pdev)
159 {
160 struct int3496_data *data = platform_get_drvdata(pdev);
161
162 devm_free_irq(&pdev->dev, data->usb_id_irq, data);
163 cancel_delayed_work_sync(&data->work);
164
165 return 0;
166 }
167
168 static const struct acpi_device_id int3496_acpi_match[] = {
169 { "INT3496" },
170 { }
171 };
172 MODULE_DEVICE_TABLE(acpi, int3496_acpi_match);
173
174 static struct platform_driver int3496_driver = {
175 .driver = {
176 .name = "intel-int3496",
177 .acpi_match_table = int3496_acpi_match,
178 },
179 .probe = int3496_probe,
180 .remove = int3496_remove,
181 };
182
183 module_platform_driver(int3496_driver);
184
185 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
186 MODULE_DESCRIPTION("Intel INT3496 ACPI device extcon driver");
187 MODULE_LICENSE("GPL v2");
188