gpio-ir-recv.c

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