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
gpio_ir_recv_irq(int irq,void * dev_id)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
gpio_ir_recv_probe(struct platform_device * pdev)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
gpio_ir_recv_suspend(struct device * dev)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
gpio_ir_recv_resume(struct device * dev)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
gpio_ir_recv_runtime_suspend(struct device * dev)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
gpio_ir_recv_runtime_resume(struct device * dev)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