1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright 2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
6 #include <linux/module.h>
7 #include <linux/interrupt.h>
8 #include <linux/delay.h>
9 #include <linux/platform_device.h>
10 #include <linux/gpio/consumer.h>
11 #include <media/cec-pin.h>
14 struct cec_adapter *adap;
17 struct gpio_desc *cec_gpio;
22 struct gpio_desc *hpd_gpio;
27 struct gpio_desc *v5_gpio;
33 static bool cec_gpio_read(struct cec_adapter *adap)
35 struct cec_gpio *cec = cec_get_drvdata(adap);
39 return gpiod_get_value(cec->cec_gpio);
42 static void cec_gpio_high(struct cec_adapter *adap)
44 struct cec_gpio *cec = cec_get_drvdata(adap);
48 cec->cec_is_low = false;
49 gpiod_set_value(cec->cec_gpio, 1);
52 static void cec_gpio_low(struct cec_adapter *adap)
54 struct cec_gpio *cec = cec_get_drvdata(adap);
58 if (WARN_ON_ONCE(cec->cec_have_irq))
59 free_irq(cec->cec_irq, cec);
60 cec->cec_have_irq = false;
61 cec->cec_is_low = true;
62 gpiod_set_value(cec->cec_gpio, 0);
65 static irqreturn_t cec_hpd_gpio_irq_handler_thread(int irq, void *priv)
67 struct cec_gpio *cec = priv;
69 cec_queue_pin_hpd_event(cec->adap, cec->hpd_is_high, cec->hpd_ts);
73 static irqreturn_t cec_5v_gpio_irq_handler(int irq, void *priv)
75 struct cec_gpio *cec = priv;
76 bool is_high = gpiod_get_value(cec->v5_gpio);
78 if (is_high == cec->v5_is_high)
80 cec->v5_ts = ktime_get();
81 cec->v5_is_high = is_high;
82 return IRQ_WAKE_THREAD;
85 static irqreturn_t cec_5v_gpio_irq_handler_thread(int irq, void *priv)
87 struct cec_gpio *cec = priv;
89 cec_queue_pin_5v_event(cec->adap, cec->v5_is_high, cec->v5_ts);
93 static irqreturn_t cec_hpd_gpio_irq_handler(int irq, void *priv)
95 struct cec_gpio *cec = priv;
96 bool is_high = gpiod_get_value(cec->hpd_gpio);
98 if (is_high == cec->hpd_is_high)
100 cec->hpd_ts = ktime_get();
101 cec->hpd_is_high = is_high;
102 return IRQ_WAKE_THREAD;
105 static irqreturn_t cec_gpio_irq_handler(int irq, void *priv)
107 struct cec_gpio *cec = priv;
109 cec_pin_changed(cec->adap, gpiod_get_value(cec->cec_gpio));
113 static bool cec_gpio_enable_irq(struct cec_adapter *adap)
115 struct cec_gpio *cec = cec_get_drvdata(adap);
117 if (cec->cec_have_irq)
120 if (request_irq(cec->cec_irq, cec_gpio_irq_handler,
121 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
124 cec->cec_have_irq = true;
128 static void cec_gpio_disable_irq(struct cec_adapter *adap)
130 struct cec_gpio *cec = cec_get_drvdata(adap);
132 if (cec->cec_have_irq)
133 free_irq(cec->cec_irq, cec);
134 cec->cec_have_irq = false;
137 static void cec_gpio_status(struct cec_adapter *adap, struct seq_file *file)
139 struct cec_gpio *cec = cec_get_drvdata(adap);
141 seq_printf(file, "mode: %s\n", cec->cec_is_low ? "low-drive" : "read");
142 if (cec->cec_have_irq)
143 seq_printf(file, "using irq: %d\n", cec->cec_irq);
145 seq_printf(file, "hpd: %s\n",
146 cec->hpd_is_high ? "high" : "low");
148 seq_printf(file, "5V: %s\n",
149 cec->v5_is_high ? "high" : "low");
152 static int cec_gpio_read_hpd(struct cec_adapter *adap)
154 struct cec_gpio *cec = cec_get_drvdata(adap);
158 return gpiod_get_value(cec->hpd_gpio);
161 static int cec_gpio_read_5v(struct cec_adapter *adap)
163 struct cec_gpio *cec = cec_get_drvdata(adap);
167 return gpiod_get_value(cec->v5_gpio);
170 static void cec_gpio_free(struct cec_adapter *adap)
172 cec_gpio_disable_irq(adap);
175 static const struct cec_pin_ops cec_gpio_pin_ops = {
176 .read = cec_gpio_read,
178 .high = cec_gpio_high,
179 .enable_irq = cec_gpio_enable_irq,
180 .disable_irq = cec_gpio_disable_irq,
181 .status = cec_gpio_status,
182 .free = cec_gpio_free,
183 .read_hpd = cec_gpio_read_hpd,
184 .read_5v = cec_gpio_read_5v,
187 static int cec_gpio_probe(struct platform_device *pdev)
189 struct device *dev = &pdev->dev;
190 struct cec_gpio *cec;
193 cec = devm_kzalloc(dev, sizeof(*cec), GFP_KERNEL);
199 cec->cec_gpio = devm_gpiod_get(dev, "cec", GPIOD_OUT_HIGH_OPEN_DRAIN);
200 if (IS_ERR(cec->cec_gpio))
201 return PTR_ERR(cec->cec_gpio);
202 cec->cec_irq = gpiod_to_irq(cec->cec_gpio);
204 cec->hpd_gpio = devm_gpiod_get_optional(dev, "hpd", GPIOD_IN);
205 if (IS_ERR(cec->hpd_gpio))
206 return PTR_ERR(cec->hpd_gpio);
208 cec->v5_gpio = devm_gpiod_get_optional(dev, "v5", GPIOD_IN);
209 if (IS_ERR(cec->v5_gpio))
210 return PTR_ERR(cec->v5_gpio);
212 cec->adap = cec_pin_allocate_adapter(&cec_gpio_pin_ops,
213 cec, pdev->name, CEC_CAP_DEFAULTS | CEC_CAP_PHYS_ADDR |
214 CEC_CAP_MONITOR_ALL | CEC_CAP_MONITOR_PIN);
215 if (IS_ERR(cec->adap))
216 return PTR_ERR(cec->adap);
219 cec->hpd_irq = gpiod_to_irq(cec->hpd_gpio);
220 ret = devm_request_threaded_irq(dev, cec->hpd_irq,
221 cec_hpd_gpio_irq_handler,
222 cec_hpd_gpio_irq_handler_thread,
224 IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
231 cec->v5_irq = gpiod_to_irq(cec->v5_gpio);
232 ret = devm_request_threaded_irq(dev, cec->v5_irq,
233 cec_5v_gpio_irq_handler,
234 cec_5v_gpio_irq_handler_thread,
236 IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
242 ret = cec_register_adapter(cec->adap, &pdev->dev);
244 cec_delete_adapter(cec->adap);
248 platform_set_drvdata(pdev, cec);
252 static int cec_gpio_remove(struct platform_device *pdev)
254 struct cec_gpio *cec = platform_get_drvdata(pdev);
256 cec_unregister_adapter(cec->adap);
260 static const struct of_device_id cec_gpio_match[] = {
262 .compatible = "cec-gpio",
266 MODULE_DEVICE_TABLE(of, cec_gpio_match);
268 static struct platform_driver cec_gpio_pdrv = {
269 .probe = cec_gpio_probe,
270 .remove = cec_gpio_remove,
273 .of_match_table = cec_gpio_match,
277 module_platform_driver(cec_gpio_pdrv);
279 MODULE_AUTHOR("Hans Verkuil <hans.verkuil@cisco.com>");
280 MODULE_LICENSE("GPL v2");
281 MODULE_DESCRIPTION("CEC GPIO driver");