xref: /openbmc/linux/drivers/media/rc/gpio-ir-recv.c (revision 99a15348)
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 
21 struct 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 
29 static 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 
60 static 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 		rc = PTR_ERR(gpio_dev->gpiod);
79 		/* Just try again if this happens */
80 		if (rc != -EPROBE_DEFER)
81 			dev_err(dev, "error getting gpio (%d)\n", rc);
82 		return rc;
83 	}
84 	gpio_dev->irq = gpiod_to_irq(gpio_dev->gpiod);
85 	if (gpio_dev->irq < 0)
86 		return gpio_dev->irq;
87 
88 	rcdev = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);
89 	if (!rcdev)
90 		return -ENOMEM;
91 
92 	rcdev->priv = gpio_dev;
93 	rcdev->device_name = GPIO_IR_DEVICE_NAME;
94 	rcdev->input_phys = GPIO_IR_DEVICE_NAME "/input0";
95 	rcdev->input_id.bustype = BUS_HOST;
96 	rcdev->input_id.vendor = 0x0001;
97 	rcdev->input_id.product = 0x0001;
98 	rcdev->input_id.version = 0x0100;
99 	rcdev->dev.parent = dev;
100 	rcdev->driver_name = KBUILD_MODNAME;
101 	rcdev->min_timeout = 1;
102 	rcdev->timeout = IR_DEFAULT_TIMEOUT;
103 	rcdev->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
104 	rcdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
105 	rcdev->map_name = of_get_property(np, "linux,rc-map-name", NULL);
106 	if (!rcdev->map_name)
107 		rcdev->map_name = RC_MAP_EMPTY;
108 
109 	gpio_dev->rcdev = rcdev;
110 
111 	rc = devm_rc_register_device(dev, rcdev);
112 	if (rc < 0) {
113 		dev_err(dev, "failed to register rc device (%d)\n", rc);
114 		return rc;
115 	}
116 
117 	of_property_read_u32(np, "linux,autosuspend-period", &period);
118 	if (period) {
119 		gpio_dev->pmdev = dev;
120 		pm_runtime_set_autosuspend_delay(dev, period);
121 		pm_runtime_use_autosuspend(dev);
122 		pm_runtime_set_suspended(dev);
123 		pm_runtime_enable(dev);
124 	}
125 
126 	platform_set_drvdata(pdev, gpio_dev);
127 
128 	return devm_request_irq(dev, gpio_dev->irq, gpio_ir_recv_irq,
129 				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
130 				"gpio-ir-recv-irq", gpio_dev);
131 }
132 
133 #ifdef CONFIG_PM
134 static int gpio_ir_recv_suspend(struct device *dev)
135 {
136 	struct gpio_rc_dev *gpio_dev = dev_get_drvdata(dev);
137 
138 	if (device_may_wakeup(dev))
139 		enable_irq_wake(gpio_dev->irq);
140 	else
141 		disable_irq(gpio_dev->irq);
142 
143 	return 0;
144 }
145 
146 static int gpio_ir_recv_resume(struct device *dev)
147 {
148 	struct gpio_rc_dev *gpio_dev = dev_get_drvdata(dev);
149 
150 	if (device_may_wakeup(dev))
151 		disable_irq_wake(gpio_dev->irq);
152 	else
153 		enable_irq(gpio_dev->irq);
154 
155 	return 0;
156 }
157 
158 static int gpio_ir_recv_runtime_suspend(struct device *dev)
159 {
160 	struct gpio_rc_dev *gpio_dev = dev_get_drvdata(dev);
161 
162 	cpu_latency_qos_remove_request(&gpio_dev->qos);
163 
164 	return 0;
165 }
166 
167 static int gpio_ir_recv_runtime_resume(struct device *dev)
168 {
169 	struct gpio_rc_dev *gpio_dev = dev_get_drvdata(dev);
170 
171 	cpu_latency_qos_add_request(&gpio_dev->qos, 0);
172 
173 	return 0;
174 }
175 
176 static const struct dev_pm_ops gpio_ir_recv_pm_ops = {
177 	.suspend        = gpio_ir_recv_suspend,
178 	.resume         = gpio_ir_recv_resume,
179 	.runtime_suspend = gpio_ir_recv_runtime_suspend,
180 	.runtime_resume  = gpio_ir_recv_runtime_resume,
181 };
182 #endif
183 
184 static const struct of_device_id gpio_ir_recv_of_match[] = {
185 	{ .compatible = "gpio-ir-receiver", },
186 	{ },
187 };
188 MODULE_DEVICE_TABLE(of, gpio_ir_recv_of_match);
189 
190 static struct platform_driver gpio_ir_recv_driver = {
191 	.probe  = gpio_ir_recv_probe,
192 	.driver = {
193 		.name   = KBUILD_MODNAME,
194 		.of_match_table = of_match_ptr(gpio_ir_recv_of_match),
195 #ifdef CONFIG_PM
196 		.pm	= &gpio_ir_recv_pm_ops,
197 #endif
198 	},
199 };
200 module_platform_driver(gpio_ir_recv_driver);
201 
202 MODULE_DESCRIPTION("GPIO IR Receiver driver");
203 MODULE_LICENSE("GPL v2");
204