1 /*
2 * Copyright (C) 2016 Texas Instruments
3 * Author: Jyri Sarha <jsarha@ti.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 as published by
7 * the Free Software Foundation.
8 *
9 */
10
11 #include <linux/delay.h>
12 #include <linux/fwnode.h>
13 #include <linux/gpio/consumer.h>
14 #include <linux/irq.h>
15 #include <linux/module.h>
16 #include <linux/of_graph.h>
17 #include <linux/platform_device.h>
18 #include <linux/i2c.h>
19
20 #include <drm/drmP.h>
21 #include <drm/drm_atomic_helper.h>
22 #include <drm/drm_crtc.h>
23 #include <drm/drm_crtc_helper.h>
24
25 #define HOTPLUG_DEBOUNCE_MS 1100
26
27 struct tfp410 {
28 struct drm_bridge bridge;
29 struct drm_connector connector;
30
31 struct i2c_adapter *ddc;
32 struct gpio_desc *hpd;
33 struct delayed_work hpd_work;
34
35 struct device *dev;
36 };
37
38 static inline struct tfp410 *
drm_bridge_to_tfp410(struct drm_bridge * bridge)39 drm_bridge_to_tfp410(struct drm_bridge *bridge)
40 {
41 return container_of(bridge, struct tfp410, bridge);
42 }
43
44 static inline struct tfp410 *
drm_connector_to_tfp410(struct drm_connector * connector)45 drm_connector_to_tfp410(struct drm_connector *connector)
46 {
47 return container_of(connector, struct tfp410, connector);
48 }
49
tfp410_get_modes(struct drm_connector * connector)50 static int tfp410_get_modes(struct drm_connector *connector)
51 {
52 struct tfp410 *dvi = drm_connector_to_tfp410(connector);
53 struct edid *edid;
54 int ret;
55
56 if (!dvi->ddc)
57 goto fallback;
58
59 edid = drm_get_edid(connector, dvi->ddc);
60 if (!edid) {
61 DRM_INFO("EDID read failed. Fallback to standard modes\n");
62 goto fallback;
63 }
64
65 drm_connector_update_edid_property(connector, edid);
66
67 ret = drm_add_edid_modes(connector, edid);
68
69 kfree(edid);
70
71 return ret;
72
73 fallback:
74 /* No EDID, fallback on the XGA standard modes */
75 ret = drm_add_modes_noedid(connector, 1920, 1200);
76
77 /* And prefer a mode pretty much anything can handle */
78 drm_set_preferred_mode(connector, 1024, 768);
79
80 return ret;
81 }
82
83 static const struct drm_connector_helper_funcs tfp410_con_helper_funcs = {
84 .get_modes = tfp410_get_modes,
85 };
86
87 static enum drm_connector_status
tfp410_connector_detect(struct drm_connector * connector,bool force)88 tfp410_connector_detect(struct drm_connector *connector, bool force)
89 {
90 struct tfp410 *dvi = drm_connector_to_tfp410(connector);
91
92 if (dvi->hpd) {
93 if (gpiod_get_value_cansleep(dvi->hpd))
94 return connector_status_connected;
95 else
96 return connector_status_disconnected;
97 }
98
99 if (dvi->ddc) {
100 if (drm_probe_ddc(dvi->ddc))
101 return connector_status_connected;
102 else
103 return connector_status_disconnected;
104 }
105
106 return connector_status_unknown;
107 }
108
109 static const struct drm_connector_funcs tfp410_con_funcs = {
110 .detect = tfp410_connector_detect,
111 .fill_modes = drm_helper_probe_single_connector_modes,
112 .destroy = drm_connector_cleanup,
113 .reset = drm_atomic_helper_connector_reset,
114 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
115 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
116 };
117
tfp410_attach(struct drm_bridge * bridge)118 static int tfp410_attach(struct drm_bridge *bridge)
119 {
120 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
121 int ret;
122
123 if (!bridge->encoder) {
124 dev_err(dvi->dev, "Missing encoder\n");
125 return -ENODEV;
126 }
127
128 if (dvi->hpd)
129 dvi->connector.polled = DRM_CONNECTOR_POLL_HPD;
130
131 drm_connector_helper_add(&dvi->connector,
132 &tfp410_con_helper_funcs);
133 ret = drm_connector_init(bridge->dev, &dvi->connector,
134 &tfp410_con_funcs, DRM_MODE_CONNECTOR_HDMIA);
135 if (ret) {
136 dev_err(dvi->dev, "drm_connector_init() failed: %d\n", ret);
137 return ret;
138 }
139
140 drm_connector_attach_encoder(&dvi->connector,
141 bridge->encoder);
142
143 return 0;
144 }
145
146 static const struct drm_bridge_funcs tfp410_bridge_funcs = {
147 .attach = tfp410_attach,
148 };
149
tfp410_hpd_work_func(struct work_struct * work)150 static void tfp410_hpd_work_func(struct work_struct *work)
151 {
152 struct tfp410 *dvi;
153
154 dvi = container_of(work, struct tfp410, hpd_work.work);
155
156 if (dvi->bridge.dev)
157 drm_helper_hpd_irq_event(dvi->bridge.dev);
158 }
159
tfp410_hpd_irq_thread(int irq,void * arg)160 static irqreturn_t tfp410_hpd_irq_thread(int irq, void *arg)
161 {
162 struct tfp410 *dvi = arg;
163
164 mod_delayed_work(system_wq, &dvi->hpd_work,
165 msecs_to_jiffies(HOTPLUG_DEBOUNCE_MS));
166
167 return IRQ_HANDLED;
168 }
169
tfp410_get_connector_properties(struct tfp410 * dvi)170 static int tfp410_get_connector_properties(struct tfp410 *dvi)
171 {
172 struct device_node *connector_node, *ddc_phandle;
173 int ret = 0;
174
175 /* port@1 is the connector node */
176 connector_node = of_graph_get_remote_node(dvi->dev->of_node, 1, -1);
177 if (!connector_node)
178 return -ENODEV;
179
180 dvi->hpd = fwnode_get_named_gpiod(&connector_node->fwnode,
181 "hpd-gpios", 0, GPIOD_IN, "hpd");
182 if (IS_ERR(dvi->hpd)) {
183 ret = PTR_ERR(dvi->hpd);
184 dvi->hpd = NULL;
185 if (ret == -ENOENT)
186 ret = 0;
187 else
188 goto fail;
189 }
190
191 ddc_phandle = of_parse_phandle(connector_node, "ddc-i2c-bus", 0);
192 if (!ddc_phandle)
193 goto fail;
194
195 dvi->ddc = of_get_i2c_adapter_by_node(ddc_phandle);
196 if (dvi->ddc)
197 dev_info(dvi->dev, "Connector's ddc i2c bus found\n");
198 else
199 ret = -EPROBE_DEFER;
200
201 of_node_put(ddc_phandle);
202
203 fail:
204 of_node_put(connector_node);
205 return ret;
206 }
207
tfp410_init(struct device * dev)208 static int tfp410_init(struct device *dev)
209 {
210 struct tfp410 *dvi;
211 int ret;
212
213 if (!dev->of_node) {
214 dev_err(dev, "device-tree data is missing\n");
215 return -ENXIO;
216 }
217
218 dvi = devm_kzalloc(dev, sizeof(*dvi), GFP_KERNEL);
219 if (!dvi)
220 return -ENOMEM;
221 dev_set_drvdata(dev, dvi);
222
223 dvi->bridge.funcs = &tfp410_bridge_funcs;
224 dvi->bridge.of_node = dev->of_node;
225 dvi->dev = dev;
226
227 ret = tfp410_get_connector_properties(dvi);
228 if (ret)
229 goto fail;
230
231 if (dvi->hpd) {
232 INIT_DELAYED_WORK(&dvi->hpd_work, tfp410_hpd_work_func);
233
234 ret = devm_request_threaded_irq(dev, gpiod_to_irq(dvi->hpd),
235 NULL, tfp410_hpd_irq_thread, IRQF_TRIGGER_RISING |
236 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
237 "hdmi-hpd", dvi);
238 if (ret) {
239 DRM_ERROR("failed to register hpd interrupt\n");
240 goto fail;
241 }
242 }
243
244 drm_bridge_add(&dvi->bridge);
245
246 return 0;
247 fail:
248 i2c_put_adapter(dvi->ddc);
249 if (dvi->hpd)
250 gpiod_put(dvi->hpd);
251 return ret;
252 }
253
tfp410_fini(struct device * dev)254 static int tfp410_fini(struct device *dev)
255 {
256 struct tfp410 *dvi = dev_get_drvdata(dev);
257
258 cancel_delayed_work_sync(&dvi->hpd_work);
259
260 drm_bridge_remove(&dvi->bridge);
261
262 if (dvi->ddc)
263 i2c_put_adapter(dvi->ddc);
264 if (dvi->hpd)
265 gpiod_put(dvi->hpd);
266
267 return 0;
268 }
269
tfp410_probe(struct platform_device * pdev)270 static int tfp410_probe(struct platform_device *pdev)
271 {
272 return tfp410_init(&pdev->dev);
273 }
274
tfp410_remove(struct platform_device * pdev)275 static int tfp410_remove(struct platform_device *pdev)
276 {
277 return tfp410_fini(&pdev->dev);
278 }
279
280 static const struct of_device_id tfp410_match[] = {
281 { .compatible = "ti,tfp410" },
282 {},
283 };
284 MODULE_DEVICE_TABLE(of, tfp410_match);
285
286 static struct platform_driver tfp410_platform_driver = {
287 .probe = tfp410_probe,
288 .remove = tfp410_remove,
289 .driver = {
290 .name = "tfp410-bridge",
291 .of_match_table = tfp410_match,
292 },
293 };
294
295 #if IS_ENABLED(CONFIG_I2C)
296 /* There is currently no i2c functionality. */
tfp410_i2c_probe(struct i2c_client * client,const struct i2c_device_id * id)297 static int tfp410_i2c_probe(struct i2c_client *client,
298 const struct i2c_device_id *id)
299 {
300 int reg;
301
302 if (!client->dev.of_node ||
303 of_property_read_u32(client->dev.of_node, "reg", ®)) {
304 dev_err(&client->dev,
305 "Can't get i2c reg property from device-tree\n");
306 return -ENXIO;
307 }
308
309 return tfp410_init(&client->dev);
310 }
311
tfp410_i2c_remove(struct i2c_client * client)312 static int tfp410_i2c_remove(struct i2c_client *client)
313 {
314 return tfp410_fini(&client->dev);
315 }
316
317 static const struct i2c_device_id tfp410_i2c_ids[] = {
318 { "tfp410", 0 },
319 { }
320 };
321 MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids);
322
323 static struct i2c_driver tfp410_i2c_driver = {
324 .driver = {
325 .name = "tfp410",
326 .of_match_table = of_match_ptr(tfp410_match),
327 },
328 .id_table = tfp410_i2c_ids,
329 .probe = tfp410_i2c_probe,
330 .remove = tfp410_i2c_remove,
331 };
332 #endif /* IS_ENABLED(CONFIG_I2C) */
333
334 static struct {
335 uint i2c:1;
336 uint platform:1;
337 } tfp410_registered_driver;
338
tfp410_module_init(void)339 static int __init tfp410_module_init(void)
340 {
341 int ret;
342
343 #if IS_ENABLED(CONFIG_I2C)
344 ret = i2c_add_driver(&tfp410_i2c_driver);
345 if (ret)
346 pr_err("%s: registering i2c driver failed: %d",
347 __func__, ret);
348 else
349 tfp410_registered_driver.i2c = 1;
350 #endif
351
352 ret = platform_driver_register(&tfp410_platform_driver);
353 if (ret)
354 pr_err("%s: registering platform driver failed: %d",
355 __func__, ret);
356 else
357 tfp410_registered_driver.platform = 1;
358
359 if (tfp410_registered_driver.i2c ||
360 tfp410_registered_driver.platform)
361 return 0;
362
363 return ret;
364 }
365 module_init(tfp410_module_init);
366
tfp410_module_exit(void)367 static void __exit tfp410_module_exit(void)
368 {
369 #if IS_ENABLED(CONFIG_I2C)
370 if (tfp410_registered_driver.i2c)
371 i2c_del_driver(&tfp410_i2c_driver);
372 #endif
373 if (tfp410_registered_driver.platform)
374 platform_driver_unregister(&tfp410_platform_driver);
375 }
376 module_exit(tfp410_module_exit);
377
378 MODULE_AUTHOR("Jyri Sarha <jsarha@ti.com>");
379 MODULE_DESCRIPTION("TI TFP410 DVI bridge driver");
380 MODULE_LICENSE("GPL");
381