1// SPDX-License-Identifier: GPL-2.0-only
2/* Copyright (c) 2012, Code Aurora Forum. All rights reserved.
3 */
4
5#include <linux/kernel.h>
6#include <linux/init.h>
7#include <linux/module.h>
8#include <linux/interrupt.h>
9#include <linux/gpio/consumer.h>
10#include <linux/slab.h>
11#include <linux/of.h>
12#include <linux/of_gpio.h>
13#include <linux/platform_device.h>
14#include <linux/pm_runtime.h>
15#include <linux/pm_qos.h>
16#include <linux/irq.h>
17#include <media/rc-core.h>
18
19#define GPIO_IR_DEVICE_NAME	"gpio_ir_recv"
20
21struct gpio_rc_dev {
22	struct rc_dev *rcdev;
23	struct gpio_desc *gpiod;
24	int irq;
25	struct device *pmdev;
26	struct pm_qos_request qos;
27};
28
29static irqreturn_t gpio_ir_recv_irq(int irq, void *dev_id)
30{
31	int val;
32	struct gpio_rc_dev *gpio_dev = dev_id;
33	struct device *pmdev = gpio_dev->pmdev;
34
35	/*
36	 * For some cpuidle systems, not all:
37	 * Respond to interrupt taking more latency when cpu in idle.
38	 * Invoke asynchronous pm runtime get from interrupt context,
39	 * this may introduce a millisecond delay to call resume callback,
40	 * where to disable cpuilde.
41	 *
42	 * Two issues lead to fail to decode first frame, one is latency to
43	 * respond to interrupt, another is delay introduced by async api.
44	 */
45	if (pmdev)
46		pm_runtime_get(pmdev);
47
48	val = gpiod_get_value(gpio_dev->gpiod);
49	if (val >= 0)
50		ir_raw_event_store_edge(gpio_dev->rcdev, val == 1);
51
52	if (pmdev) {
53		pm_runtime_mark_last_busy(pmdev);
54		pm_runtime_put_autosuspend(pmdev);
55	}
56
57	return IRQ_HANDLED;
58}
59
60static int gpio_ir_recv_probe(struct platform_device *pdev)
61{
62	struct device *dev = &pdev->dev;
63	struct device_node *np = dev->of_node;
64	struct gpio_rc_dev *gpio_dev;
65	struct rc_dev *rcdev;
66	u32 period = 0;
67	int rc;
68
69	if (!np)
70		return -ENODEV;
71
72	gpio_dev = devm_kzalloc(dev, sizeof(*gpio_dev), GFP_KERNEL);
73	if (!gpio_dev)
74		return -ENOMEM;
75
76	gpio_dev->gpiod = devm_gpiod_get(dev, NULL, GPIOD_IN);
77	if (IS_ERR(gpio_dev->gpiod))
78		return dev_err_probe(dev, PTR_ERR(gpio_dev->gpiod),
79				     "error getting gpio\n");
80	gpio_dev->irq = gpiod_to_irq(gpio_dev->gpiod);
81	if (gpio_dev->irq < 0)
82		return gpio_dev->irq;
83
84	rcdev = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);
85	if (!rcdev)
86		return -ENOMEM;
87
88	rcdev->priv = gpio_dev;
89	rcdev->device_name = GPIO_IR_DEVICE_NAME;
90	rcdev->input_phys = GPIO_IR_DEVICE_NAME "/input0";
91	rcdev->input_id.bustype = BUS_HOST;
92	rcdev->input_id.vendor = 0x0001;
93	rcdev->input_id.product = 0x0001;
94	rcdev->input_id.version = 0x0100;
95	rcdev->dev.parent = dev;
96	rcdev->driver_name = KBUILD_MODNAME;
97	rcdev->min_timeout = 1;
98	rcdev->timeout = IR_DEFAULT_TIMEOUT;
99	rcdev->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
100	rcdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
101	rcdev->map_name = of_get_property(np, "linux,rc-map-name", NULL);
102	if (!rcdev->map_name)
103		rcdev->map_name = RC_MAP_EMPTY;
104
105	gpio_dev->rcdev = rcdev;
106	if (of_property_read_bool(np, "wakeup-source"))
107		device_init_wakeup(dev, true);
108
109	rc = devm_rc_register_device(dev, rcdev);
110	if (rc < 0) {
111		dev_err(dev, "failed to register rc device (%d)\n", rc);
112		return rc;
113	}
114
115	of_property_read_u32(np, "linux,autosuspend-period", &period);
116	if (period) {
117		gpio_dev->pmdev = dev;
118		pm_runtime_set_autosuspend_delay(dev, period);
119		pm_runtime_use_autosuspend(dev);
120		pm_runtime_set_suspended(dev);
121		pm_runtime_enable(dev);
122	}
123
124	platform_set_drvdata(pdev, gpio_dev);
125
126	return devm_request_irq(dev, gpio_dev->irq, gpio_ir_recv_irq,
127				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
128				"gpio-ir-recv-irq", gpio_dev);
129}
130
131static void gpio_ir_recv_remove(struct platform_device *pdev)
132{
133	struct gpio_rc_dev *gpio_dev = platform_get_drvdata(pdev);
134	struct device *pmdev = gpio_dev->pmdev;
135
136	if (pmdev) {
137		pm_runtime_get_sync(pmdev);
138		cpu_latency_qos_remove_request(&gpio_dev->qos);
139
140		pm_runtime_disable(pmdev);
141		pm_runtime_put_noidle(pmdev);
142		pm_runtime_set_suspended(pmdev);
143	}
144}
145
146#ifdef CONFIG_PM
147static int gpio_ir_recv_suspend(struct device *dev)
148{
149	struct gpio_rc_dev *gpio_dev = dev_get_drvdata(dev);
150
151	if (device_may_wakeup(dev))
152		enable_irq_wake(gpio_dev->irq);
153	else
154		disable_irq(gpio_dev->irq);
155
156	return 0;
157}
158
159static int gpio_ir_recv_resume(struct device *dev)
160{
161	struct gpio_rc_dev *gpio_dev = dev_get_drvdata(dev);
162
163	if (device_may_wakeup(dev))
164		disable_irq_wake(gpio_dev->irq);
165	else
166		enable_irq(gpio_dev->irq);
167
168	return 0;
169}
170
171static int gpio_ir_recv_runtime_suspend(struct device *dev)
172{
173	struct gpio_rc_dev *gpio_dev = dev_get_drvdata(dev);
174
175	cpu_latency_qos_remove_request(&gpio_dev->qos);
176
177	return 0;
178}
179
180static int gpio_ir_recv_runtime_resume(struct device *dev)
181{
182	struct gpio_rc_dev *gpio_dev = dev_get_drvdata(dev);
183
184	cpu_latency_qos_add_request(&gpio_dev->qos, 0);
185
186	return 0;
187}
188
189static const struct dev_pm_ops gpio_ir_recv_pm_ops = {
190	.suspend        = gpio_ir_recv_suspend,
191	.resume         = gpio_ir_recv_resume,
192	.runtime_suspend = gpio_ir_recv_runtime_suspend,
193	.runtime_resume  = gpio_ir_recv_runtime_resume,
194};
195#endif
196
197static const struct of_device_id gpio_ir_recv_of_match[] = {
198	{ .compatible = "gpio-ir-receiver", },
199	{ },
200};
201MODULE_DEVICE_TABLE(of, gpio_ir_recv_of_match);
202
203static struct platform_driver gpio_ir_recv_driver = {
204	.probe  = gpio_ir_recv_probe,
205	.remove_new = gpio_ir_recv_remove,
206	.driver = {
207		.name   = KBUILD_MODNAME,
208		.of_match_table = gpio_ir_recv_of_match,
209#ifdef CONFIG_PM
210		.pm	= &gpio_ir_recv_pm_ops,
211#endif
212	},
213};
214module_platform_driver(gpio_ir_recv_driver);
215
216MODULE_DESCRIPTION("GPIO IR Receiver driver");
217MODULE_LICENSE("GPL v2");
218