This source file includes following definitions.
- cec_gpio_read
- cec_gpio_high
- cec_gpio_low
- cec_hpd_gpio_irq_handler_thread
- cec_5v_gpio_irq_handler
- cec_5v_gpio_irq_handler_thread
- cec_hpd_gpio_irq_handler
- cec_gpio_irq_handler
- cec_gpio_enable_irq
- cec_gpio_disable_irq
- cec_gpio_status
- cec_gpio_read_hpd
- cec_gpio_read_5v
- cec_gpio_free
- cec_gpio_probe
- cec_gpio_remove
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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>
12
13 struct cec_gpio {
14 struct cec_adapter *adap;
15 struct device *dev;
16
17 struct gpio_desc *cec_gpio;
18 int cec_irq;
19 bool cec_is_low;
20
21 struct gpio_desc *hpd_gpio;
22 int hpd_irq;
23 bool hpd_is_high;
24 ktime_t hpd_ts;
25
26 struct gpio_desc *v5_gpio;
27 int v5_irq;
28 bool v5_is_high;
29 ktime_t v5_ts;
30 };
31
32 static bool cec_gpio_read(struct cec_adapter *adap)
33 {
34 struct cec_gpio *cec = cec_get_drvdata(adap);
35
36 if (cec->cec_is_low)
37 return false;
38 return gpiod_get_value(cec->cec_gpio);
39 }
40
41 static void cec_gpio_high(struct cec_adapter *adap)
42 {
43 struct cec_gpio *cec = cec_get_drvdata(adap);
44
45 if (!cec->cec_is_low)
46 return;
47 cec->cec_is_low = false;
48 gpiod_set_value(cec->cec_gpio, 1);
49 }
50
51 static void cec_gpio_low(struct cec_adapter *adap)
52 {
53 struct cec_gpio *cec = cec_get_drvdata(adap);
54
55 if (cec->cec_is_low)
56 return;
57 cec->cec_is_low = true;
58 gpiod_set_value(cec->cec_gpio, 0);
59 }
60
61 static irqreturn_t cec_hpd_gpio_irq_handler_thread(int irq, void *priv)
62 {
63 struct cec_gpio *cec = priv;
64
65 cec_queue_pin_hpd_event(cec->adap, cec->hpd_is_high, cec->hpd_ts);
66 return IRQ_HANDLED;
67 }
68
69 static irqreturn_t cec_5v_gpio_irq_handler(int irq, void *priv)
70 {
71 struct cec_gpio *cec = priv;
72 bool is_high = gpiod_get_value(cec->v5_gpio);
73
74 if (is_high == cec->v5_is_high)
75 return IRQ_HANDLED;
76 cec->v5_ts = ktime_get();
77 cec->v5_is_high = is_high;
78 return IRQ_WAKE_THREAD;
79 }
80
81 static irqreturn_t cec_5v_gpio_irq_handler_thread(int irq, void *priv)
82 {
83 struct cec_gpio *cec = priv;
84
85 cec_queue_pin_5v_event(cec->adap, cec->v5_is_high, cec->v5_ts);
86 return IRQ_HANDLED;
87 }
88
89 static irqreturn_t cec_hpd_gpio_irq_handler(int irq, void *priv)
90 {
91 struct cec_gpio *cec = priv;
92 bool is_high = gpiod_get_value(cec->hpd_gpio);
93
94 if (is_high == cec->hpd_is_high)
95 return IRQ_HANDLED;
96 cec->hpd_ts = ktime_get();
97 cec->hpd_is_high = is_high;
98 return IRQ_WAKE_THREAD;
99 }
100
101 static irqreturn_t cec_gpio_irq_handler(int irq, void *priv)
102 {
103 struct cec_gpio *cec = priv;
104
105 cec_pin_changed(cec->adap, gpiod_get_value(cec->cec_gpio));
106 return IRQ_HANDLED;
107 }
108
109 static bool cec_gpio_enable_irq(struct cec_adapter *adap)
110 {
111 struct cec_gpio *cec = cec_get_drvdata(adap);
112
113 enable_irq(cec->cec_irq);
114 return true;
115 }
116
117 static void cec_gpio_disable_irq(struct cec_adapter *adap)
118 {
119 struct cec_gpio *cec = cec_get_drvdata(adap);
120
121 disable_irq(cec->cec_irq);
122 }
123
124 static void cec_gpio_status(struct cec_adapter *adap, struct seq_file *file)
125 {
126 struct cec_gpio *cec = cec_get_drvdata(adap);
127
128 seq_printf(file, "mode: %s\n", cec->cec_is_low ? "low-drive" : "read");
129 seq_printf(file, "using irq: %d\n", cec->cec_irq);
130 if (cec->hpd_gpio)
131 seq_printf(file, "hpd: %s\n",
132 cec->hpd_is_high ? "high" : "low");
133 if (cec->v5_gpio)
134 seq_printf(file, "5V: %s\n",
135 cec->v5_is_high ? "high" : "low");
136 }
137
138 static int cec_gpio_read_hpd(struct cec_adapter *adap)
139 {
140 struct cec_gpio *cec = cec_get_drvdata(adap);
141
142 if (!cec->hpd_gpio)
143 return -ENOTTY;
144 return gpiod_get_value(cec->hpd_gpio);
145 }
146
147 static int cec_gpio_read_5v(struct cec_adapter *adap)
148 {
149 struct cec_gpio *cec = cec_get_drvdata(adap);
150
151 if (!cec->v5_gpio)
152 return -ENOTTY;
153 return gpiod_get_value(cec->v5_gpio);
154 }
155
156 static void cec_gpio_free(struct cec_adapter *adap)
157 {
158 cec_gpio_disable_irq(adap);
159 }
160
161 static const struct cec_pin_ops cec_gpio_pin_ops = {
162 .read = cec_gpio_read,
163 .low = cec_gpio_low,
164 .high = cec_gpio_high,
165 .enable_irq = cec_gpio_enable_irq,
166 .disable_irq = cec_gpio_disable_irq,
167 .status = cec_gpio_status,
168 .free = cec_gpio_free,
169 .read_hpd = cec_gpio_read_hpd,
170 .read_5v = cec_gpio_read_5v,
171 };
172
173 static int cec_gpio_probe(struct platform_device *pdev)
174 {
175 struct device *dev = &pdev->dev;
176 struct cec_gpio *cec;
177 int ret;
178
179 cec = devm_kzalloc(dev, sizeof(*cec), GFP_KERNEL);
180 if (!cec)
181 return -ENOMEM;
182
183 cec->dev = dev;
184
185 cec->cec_gpio = devm_gpiod_get(dev, "cec", GPIOD_OUT_HIGH_OPEN_DRAIN);
186 if (IS_ERR(cec->cec_gpio))
187 return PTR_ERR(cec->cec_gpio);
188 cec->cec_irq = gpiod_to_irq(cec->cec_gpio);
189
190 cec->hpd_gpio = devm_gpiod_get_optional(dev, "hpd", GPIOD_IN);
191 if (IS_ERR(cec->hpd_gpio))
192 return PTR_ERR(cec->hpd_gpio);
193
194 cec->v5_gpio = devm_gpiod_get_optional(dev, "v5", GPIOD_IN);
195 if (IS_ERR(cec->v5_gpio))
196 return PTR_ERR(cec->v5_gpio);
197
198 cec->adap = cec_pin_allocate_adapter(&cec_gpio_pin_ops,
199 cec, pdev->name, CEC_CAP_DEFAULTS | CEC_CAP_PHYS_ADDR |
200 CEC_CAP_MONITOR_ALL | CEC_CAP_MONITOR_PIN);
201 if (IS_ERR(cec->adap))
202 return PTR_ERR(cec->adap);
203
204 ret = devm_request_irq(dev, cec->cec_irq, cec_gpio_irq_handler,
205 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
206 cec->adap->name, cec);
207 if (ret)
208 return ret;
209
210 cec_gpio_disable_irq(cec->adap);
211
212 if (cec->hpd_gpio) {
213 cec->hpd_irq = gpiod_to_irq(cec->hpd_gpio);
214 ret = devm_request_threaded_irq(dev, cec->hpd_irq,
215 cec_hpd_gpio_irq_handler,
216 cec_hpd_gpio_irq_handler_thread,
217 IRQF_ONESHOT |
218 IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
219 "hpd-gpio", cec);
220 if (ret)
221 return ret;
222 }
223
224 if (cec->v5_gpio) {
225 cec->v5_irq = gpiod_to_irq(cec->v5_gpio);
226 ret = devm_request_threaded_irq(dev, cec->v5_irq,
227 cec_5v_gpio_irq_handler,
228 cec_5v_gpio_irq_handler_thread,
229 IRQF_ONESHOT |
230 IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
231 "v5-gpio", cec);
232 if (ret)
233 return ret;
234 }
235
236 ret = cec_register_adapter(cec->adap, &pdev->dev);
237 if (ret) {
238 cec_delete_adapter(cec->adap);
239 return ret;
240 }
241
242 platform_set_drvdata(pdev, cec);
243 return 0;
244 }
245
246 static int cec_gpio_remove(struct platform_device *pdev)
247 {
248 struct cec_gpio *cec = platform_get_drvdata(pdev);
249
250 cec_unregister_adapter(cec->adap);
251 return 0;
252 }
253
254 static const struct of_device_id cec_gpio_match[] = {
255 {
256 .compatible = "cec-gpio",
257 },
258 {},
259 };
260 MODULE_DEVICE_TABLE(of, cec_gpio_match);
261
262 static struct platform_driver cec_gpio_pdrv = {
263 .probe = cec_gpio_probe,
264 .remove = cec_gpio_remove,
265 .driver = {
266 .name = "cec-gpio",
267 .of_match_table = cec_gpio_match,
268 },
269 };
270
271 module_platform_driver(cec_gpio_pdrv);
272
273 MODULE_AUTHOR("Hans Verkuil <hans.verkuil@cisco.com>");
274 MODULE_LICENSE("GPL v2");
275 MODULE_DESCRIPTION("CEC GPIO driver");