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/devm-helpers.h>
15 #include <linux/extcon-provider.h>
16 #include <linux/gpio/consumer.h>
17 #include <linux/interrupt.h>
18 #include <linux/module.h>
19 #include <linux/platform_device.h>
20 #include <linux/regulator/consumer.h>
21
22 #define INT3496_GPIO_USB_ID 0
23 #define INT3496_GPIO_VBUS_EN 1
24 #define INT3496_GPIO_USB_MUX 2
25 #define DEBOUNCE_TIME msecs_to_jiffies(50)
26
27 struct int3496_data {
28 struct device *dev;
29 struct extcon_dev *edev;
30 struct delayed_work work;
31 struct gpio_desc *gpio_usb_id;
32 struct gpio_desc *gpio_vbus_en;
33 struct gpio_desc *gpio_usb_mux;
34 struct regulator *vbus_boost;
35 int usb_id_irq;
36 bool vbus_boost_enabled;
37 };
38
39 static const unsigned int int3496_cable[] = {
40 EXTCON_USB_HOST,
41 EXTCON_NONE,
42 };
43
44 static const struct acpi_gpio_params id_gpios = { INT3496_GPIO_USB_ID, 0, false };
45 static const struct acpi_gpio_params vbus_gpios = { INT3496_GPIO_VBUS_EN, 0, false };
46 static const struct acpi_gpio_params mux_gpios = { INT3496_GPIO_USB_MUX, 0, false };
47
48 static const struct acpi_gpio_mapping acpi_int3496_default_gpios[] = {
49 /*
50 * Some platforms have a bug in ACPI GPIO description making IRQ
51 * GPIO to be output only. Ask the GPIO core to ignore this limit.
52 */
53 { "id-gpios", &id_gpios, 1, ACPI_GPIO_QUIRK_NO_IO_RESTRICTION },
54 { "vbus-gpios", &vbus_gpios, 1 },
55 { "mux-gpios", &mux_gpios, 1 },
56 { },
57 };
58
int3496_set_vbus_boost(struct int3496_data * data,bool enable)59 static void int3496_set_vbus_boost(struct int3496_data *data, bool enable)
60 {
61 int ret;
62
63 if (IS_ERR_OR_NULL(data->vbus_boost))
64 return;
65
66 if (data->vbus_boost_enabled == enable)
67 return;
68
69 if (enable)
70 ret = regulator_enable(data->vbus_boost);
71 else
72 ret = regulator_disable(data->vbus_boost);
73
74 if (ret == 0)
75 data->vbus_boost_enabled = enable;
76 else
77 dev_err(data->dev, "Error updating Vbus boost regulator: %d\n", ret);
78 }
79
int3496_do_usb_id(struct work_struct * work)80 static void int3496_do_usb_id(struct work_struct *work)
81 {
82 struct int3496_data *data =
83 container_of(work, struct int3496_data, work.work);
84 int id = gpiod_get_value_cansleep(data->gpio_usb_id);
85
86 /* id == 1: PERIPHERAL, id == 0: HOST */
87 dev_dbg(data->dev, "Connected %s cable\n", id ? "PERIPHERAL" : "HOST");
88
89 /*
90 * Peripheral: set USB mux to peripheral and disable VBUS
91 * Host: set USB mux to host and enable VBUS
92 */
93 if (!IS_ERR(data->gpio_usb_mux))
94 gpiod_direction_output(data->gpio_usb_mux, id);
95
96 if (!IS_ERR(data->gpio_vbus_en))
97 gpiod_direction_output(data->gpio_vbus_en, !id);
98 else
99 int3496_set_vbus_boost(data, !id);
100
101 extcon_set_state_sync(data->edev, EXTCON_USB_HOST, !id);
102 }
103
int3496_thread_isr(int irq,void * priv)104 static irqreturn_t int3496_thread_isr(int irq, void *priv)
105 {
106 struct int3496_data *data = priv;
107
108 /* Let the pin settle before processing it */
109 mod_delayed_work(system_wq, &data->work, DEBOUNCE_TIME);
110
111 return IRQ_HANDLED;
112 }
113
int3496_probe(struct platform_device * pdev)114 static int int3496_probe(struct platform_device *pdev)
115 {
116 struct device *dev = &pdev->dev;
117 struct int3496_data *data;
118 int ret;
119
120 if (has_acpi_companion(dev)) {
121 ret = devm_acpi_dev_add_driver_gpios(dev, acpi_int3496_default_gpios);
122 if (ret) {
123 dev_err(dev, "can't add GPIO ACPI mapping\n");
124 return ret;
125 }
126 }
127
128 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
129 if (!data)
130 return -ENOMEM;
131
132 data->dev = dev;
133 ret = devm_delayed_work_autocancel(dev, &data->work, int3496_do_usb_id);
134 if (ret)
135 return ret;
136
137 data->gpio_usb_id =
138 devm_gpiod_get(dev, "id", GPIOD_IN | GPIOD_FLAGS_BIT_NONEXCLUSIVE);
139 if (IS_ERR(data->gpio_usb_id)) {
140 ret = PTR_ERR(data->gpio_usb_id);
141 dev_err(dev, "can't request USB ID GPIO: %d\n", ret);
142 return ret;
143 }
144
145 data->usb_id_irq = gpiod_to_irq(data->gpio_usb_id);
146 if (data->usb_id_irq < 0) {
147 dev_err(dev, "can't get USB ID IRQ: %d\n", data->usb_id_irq);
148 return data->usb_id_irq;
149 }
150
151 data->gpio_vbus_en = devm_gpiod_get(dev, "vbus", GPIOD_ASIS);
152 if (IS_ERR(data->gpio_vbus_en)) {
153 dev_dbg(dev, "can't request VBUS EN GPIO\n");
154 data->vbus_boost = devm_regulator_get_optional(dev, "vbus");
155 }
156
157 data->gpio_usb_mux = devm_gpiod_get(dev, "mux", GPIOD_ASIS);
158 if (IS_ERR(data->gpio_usb_mux))
159 dev_dbg(dev, "can't request USB MUX GPIO\n");
160
161 /* register extcon device */
162 data->edev = devm_extcon_dev_allocate(dev, int3496_cable);
163 if (IS_ERR(data->edev))
164 return -ENOMEM;
165
166 ret = devm_extcon_dev_register(dev, data->edev);
167 if (ret < 0) {
168 dev_err(dev, "can't register extcon device: %d\n", ret);
169 return ret;
170 }
171
172 ret = devm_request_threaded_irq(dev, data->usb_id_irq,
173 NULL, int3496_thread_isr,
174 IRQF_SHARED | IRQF_ONESHOT |
175 IRQF_TRIGGER_RISING |
176 IRQF_TRIGGER_FALLING,
177 dev_name(dev), data);
178 if (ret < 0) {
179 dev_err(dev, "can't request IRQ for USB ID GPIO: %d\n", ret);
180 return ret;
181 }
182
183 /* process id-pin so that we start with the right status */
184 queue_delayed_work(system_wq, &data->work, 0);
185 flush_delayed_work(&data->work);
186
187 platform_set_drvdata(pdev, data);
188
189 return 0;
190 }
191
192 static const struct acpi_device_id int3496_acpi_match[] = {
193 { "INT3496" },
194 { }
195 };
196 MODULE_DEVICE_TABLE(acpi, int3496_acpi_match);
197
198 static const struct platform_device_id int3496_ids[] = {
199 { .name = "intel-int3496" },
200 {},
201 };
202 MODULE_DEVICE_TABLE(platform, int3496_ids);
203
204 static struct platform_driver int3496_driver = {
205 .driver = {
206 .name = "intel-int3496",
207 .acpi_match_table = int3496_acpi_match,
208 },
209 .probe = int3496_probe,
210 .id_table = int3496_ids,
211 };
212
213 module_platform_driver(int3496_driver);
214
215 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
216 MODULE_DESCRIPTION("Intel INT3496 ACPI device extcon driver");
217 MODULE_LICENSE("GPL v2");
218