1 /*
2 * Generic DVI Connector driver
3 *
4 * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com/
5 * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 as published by
9 * the Free Software Foundation.
10 */
11
12 #include <linux/gpio/consumer.h>
13 #include <linux/i2c.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/slab.h>
17
18 #include <drm/drm_edid.h>
19
20 #include "../dss/omapdss.h"
21
22 static const struct videomode dvic_default_vm = {
23 .hactive = 640,
24 .vactive = 480,
25
26 .pixelclock = 23500000,
27
28 .hfront_porch = 48,
29 .hsync_len = 32,
30 .hback_porch = 80,
31
32 .vfront_porch = 3,
33 .vsync_len = 4,
34 .vback_porch = 7,
35
36 .flags = DISPLAY_FLAGS_HSYNC_HIGH | DISPLAY_FLAGS_VSYNC_HIGH |
37 DISPLAY_FLAGS_SYNC_NEGEDGE | DISPLAY_FLAGS_DE_HIGH |
38 DISPLAY_FLAGS_PIXDATA_POSEDGE,
39 };
40
41 struct panel_drv_data {
42 struct omap_dss_device dssdev;
43 struct omap_dss_device *in;
44
45 struct videomode vm;
46
47 struct i2c_adapter *i2c_adapter;
48
49 struct gpio_desc *hpd_gpio;
50
51 void (*hpd_cb)(void *cb_data, enum drm_connector_status status);
52 void *hpd_cb_data;
53 bool hpd_enabled;
54 /* mutex for hpd fields above */
55 struct mutex hpd_lock;
56 };
57
58 #define to_panel_data(x) container_of(x, struct panel_drv_data, dssdev)
59
dvic_connect(struct omap_dss_device * dssdev)60 static int dvic_connect(struct omap_dss_device *dssdev)
61 {
62 struct panel_drv_data *ddata = to_panel_data(dssdev);
63 struct omap_dss_device *in;
64 int r;
65
66 if (omapdss_device_is_connected(dssdev))
67 return 0;
68
69 in = omapdss_of_find_source_for_first_ep(dssdev->dev->of_node);
70 if (IS_ERR(in)) {
71 dev_err(dssdev->dev, "failed to find video source\n");
72 return PTR_ERR(in);
73 }
74
75 r = in->ops.dvi->connect(in, dssdev);
76 if (r) {
77 omap_dss_put_device(in);
78 return r;
79 }
80
81 ddata->in = in;
82 return 0;
83 }
84
dvic_disconnect(struct omap_dss_device * dssdev)85 static void dvic_disconnect(struct omap_dss_device *dssdev)
86 {
87 struct panel_drv_data *ddata = to_panel_data(dssdev);
88 struct omap_dss_device *in = ddata->in;
89
90 if (!omapdss_device_is_connected(dssdev))
91 return;
92
93 in->ops.dvi->disconnect(in, dssdev);
94
95 omap_dss_put_device(in);
96 ddata->in = NULL;
97 }
98
dvic_enable(struct omap_dss_device * dssdev)99 static int dvic_enable(struct omap_dss_device *dssdev)
100 {
101 struct panel_drv_data *ddata = to_panel_data(dssdev);
102 struct omap_dss_device *in = ddata->in;
103 int r;
104
105 if (!omapdss_device_is_connected(dssdev))
106 return -ENODEV;
107
108 if (omapdss_device_is_enabled(dssdev))
109 return 0;
110
111 in->ops.dvi->set_timings(in, &ddata->vm);
112
113 r = in->ops.dvi->enable(in);
114 if (r)
115 return r;
116
117 dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;
118
119 return 0;
120 }
121
dvic_disable(struct omap_dss_device * dssdev)122 static void dvic_disable(struct omap_dss_device *dssdev)
123 {
124 struct panel_drv_data *ddata = to_panel_data(dssdev);
125 struct omap_dss_device *in = ddata->in;
126
127 if (!omapdss_device_is_enabled(dssdev))
128 return;
129
130 in->ops.dvi->disable(in);
131
132 dssdev->state = OMAP_DSS_DISPLAY_DISABLED;
133 }
134
dvic_set_timings(struct omap_dss_device * dssdev,struct videomode * vm)135 static void dvic_set_timings(struct omap_dss_device *dssdev,
136 struct videomode *vm)
137 {
138 struct panel_drv_data *ddata = to_panel_data(dssdev);
139 struct omap_dss_device *in = ddata->in;
140
141 ddata->vm = *vm;
142 dssdev->panel.vm = *vm;
143
144 in->ops.dvi->set_timings(in, vm);
145 }
146
dvic_get_timings(struct omap_dss_device * dssdev,struct videomode * vm)147 static void dvic_get_timings(struct omap_dss_device *dssdev,
148 struct videomode *vm)
149 {
150 struct panel_drv_data *ddata = to_panel_data(dssdev);
151
152 *vm = ddata->vm;
153 }
154
dvic_check_timings(struct omap_dss_device * dssdev,struct videomode * vm)155 static int dvic_check_timings(struct omap_dss_device *dssdev,
156 struct videomode *vm)
157 {
158 struct panel_drv_data *ddata = to_panel_data(dssdev);
159 struct omap_dss_device *in = ddata->in;
160
161 return in->ops.dvi->check_timings(in, vm);
162 }
163
dvic_ddc_read(struct i2c_adapter * adapter,unsigned char * buf,u16 count,u8 offset)164 static int dvic_ddc_read(struct i2c_adapter *adapter,
165 unsigned char *buf, u16 count, u8 offset)
166 {
167 int r, retries;
168
169 for (retries = 3; retries > 0; retries--) {
170 struct i2c_msg msgs[] = {
171 {
172 .addr = DDC_ADDR,
173 .flags = 0,
174 .len = 1,
175 .buf = &offset,
176 }, {
177 .addr = DDC_ADDR,
178 .flags = I2C_M_RD,
179 .len = count,
180 .buf = buf,
181 }
182 };
183
184 r = i2c_transfer(adapter, msgs, 2);
185 if (r == 2)
186 return 0;
187
188 if (r != -EAGAIN)
189 break;
190 }
191
192 return r < 0 ? r : -EIO;
193 }
194
dvic_read_edid(struct omap_dss_device * dssdev,u8 * edid,int len)195 static int dvic_read_edid(struct omap_dss_device *dssdev,
196 u8 *edid, int len)
197 {
198 struct panel_drv_data *ddata = to_panel_data(dssdev);
199 int r, l, bytes_read;
200
201 if (ddata->hpd_gpio && !gpiod_get_value_cansleep(ddata->hpd_gpio))
202 return -ENODEV;
203
204 if (!ddata->i2c_adapter)
205 return -ENODEV;
206
207 l = min(EDID_LENGTH, len);
208 r = dvic_ddc_read(ddata->i2c_adapter, edid, l, 0);
209 if (r)
210 return r;
211
212 bytes_read = l;
213
214 /* if there are extensions, read second block */
215 if (len > EDID_LENGTH && edid[0x7e] > 0) {
216 l = min(EDID_LENGTH, len - EDID_LENGTH);
217
218 r = dvic_ddc_read(ddata->i2c_adapter, edid + EDID_LENGTH,
219 l, EDID_LENGTH);
220 if (r)
221 return r;
222
223 bytes_read += l;
224 }
225
226 return bytes_read;
227 }
228
dvic_detect(struct omap_dss_device * dssdev)229 static bool dvic_detect(struct omap_dss_device *dssdev)
230 {
231 struct panel_drv_data *ddata = to_panel_data(dssdev);
232 unsigned char out;
233 int r;
234
235 if (ddata->hpd_gpio)
236 return gpiod_get_value_cansleep(ddata->hpd_gpio);
237
238 if (!ddata->i2c_adapter)
239 return true;
240
241 r = dvic_ddc_read(ddata->i2c_adapter, &out, 1, 0);
242
243 return r == 0;
244 }
245
dvic_register_hpd_cb(struct omap_dss_device * dssdev,void (* cb)(void * cb_data,enum drm_connector_status status),void * cb_data)246 static int dvic_register_hpd_cb(struct omap_dss_device *dssdev,
247 void (*cb)(void *cb_data,
248 enum drm_connector_status status),
249 void *cb_data)
250 {
251 struct panel_drv_data *ddata = to_panel_data(dssdev);
252
253 if (!ddata->hpd_gpio)
254 return -ENOTSUPP;
255
256 mutex_lock(&ddata->hpd_lock);
257 ddata->hpd_cb = cb;
258 ddata->hpd_cb_data = cb_data;
259 mutex_unlock(&ddata->hpd_lock);
260 return 0;
261 }
262
dvic_unregister_hpd_cb(struct omap_dss_device * dssdev)263 static void dvic_unregister_hpd_cb(struct omap_dss_device *dssdev)
264 {
265 struct panel_drv_data *ddata = to_panel_data(dssdev);
266
267 if (!ddata->hpd_gpio)
268 return;
269
270 mutex_lock(&ddata->hpd_lock);
271 ddata->hpd_cb = NULL;
272 ddata->hpd_cb_data = NULL;
273 mutex_unlock(&ddata->hpd_lock);
274 }
275
dvic_enable_hpd(struct omap_dss_device * dssdev)276 static void dvic_enable_hpd(struct omap_dss_device *dssdev)
277 {
278 struct panel_drv_data *ddata = to_panel_data(dssdev);
279
280 if (!ddata->hpd_gpio)
281 return;
282
283 mutex_lock(&ddata->hpd_lock);
284 ddata->hpd_enabled = true;
285 mutex_unlock(&ddata->hpd_lock);
286 }
287
dvic_disable_hpd(struct omap_dss_device * dssdev)288 static void dvic_disable_hpd(struct omap_dss_device *dssdev)
289 {
290 struct panel_drv_data *ddata = to_panel_data(dssdev);
291
292 if (!ddata->hpd_gpio)
293 return;
294
295 mutex_lock(&ddata->hpd_lock);
296 ddata->hpd_enabled = false;
297 mutex_unlock(&ddata->hpd_lock);
298 }
299
300 static struct omap_dss_driver dvic_driver = {
301 .connect = dvic_connect,
302 .disconnect = dvic_disconnect,
303
304 .enable = dvic_enable,
305 .disable = dvic_disable,
306
307 .set_timings = dvic_set_timings,
308 .get_timings = dvic_get_timings,
309 .check_timings = dvic_check_timings,
310
311 .read_edid = dvic_read_edid,
312 .detect = dvic_detect,
313
314 .register_hpd_cb = dvic_register_hpd_cb,
315 .unregister_hpd_cb = dvic_unregister_hpd_cb,
316 .enable_hpd = dvic_enable_hpd,
317 .disable_hpd = dvic_disable_hpd,
318 };
319
dvic_hpd_isr(int irq,void * data)320 static irqreturn_t dvic_hpd_isr(int irq, void *data)
321 {
322 struct panel_drv_data *ddata = data;
323
324 mutex_lock(&ddata->hpd_lock);
325 if (ddata->hpd_enabled && ddata->hpd_cb) {
326 enum drm_connector_status status;
327
328 if (dvic_detect(&ddata->dssdev))
329 status = connector_status_connected;
330 else
331 status = connector_status_disconnected;
332
333 ddata->hpd_cb(ddata->hpd_cb_data, status);
334 }
335 mutex_unlock(&ddata->hpd_lock);
336
337 return IRQ_HANDLED;
338 }
339
dvic_probe_of(struct platform_device * pdev)340 static int dvic_probe_of(struct platform_device *pdev)
341 {
342 struct panel_drv_data *ddata = platform_get_drvdata(pdev);
343 struct device_node *node = pdev->dev.of_node;
344 struct device_node *adapter_node;
345 struct i2c_adapter *adapter;
346 struct gpio_desc *gpio;
347 int r;
348
349 gpio = devm_gpiod_get_optional(&pdev->dev, "hpd", GPIOD_IN);
350 if (IS_ERR(gpio)) {
351 dev_err(&pdev->dev, "failed to parse HPD gpio\n");
352 return PTR_ERR(gpio);
353 }
354
355 ddata->hpd_gpio = gpio;
356
357 mutex_init(&ddata->hpd_lock);
358
359 if (ddata->hpd_gpio) {
360 r = devm_request_threaded_irq(&pdev->dev,
361 gpiod_to_irq(ddata->hpd_gpio), NULL, dvic_hpd_isr,
362 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
363 "DVI HPD", ddata);
364 if (r)
365 return r;
366 }
367
368 adapter_node = of_parse_phandle(node, "ddc-i2c-bus", 0);
369 if (adapter_node) {
370 adapter = of_get_i2c_adapter_by_node(adapter_node);
371 of_node_put(adapter_node);
372 if (adapter == NULL) {
373 dev_err(&pdev->dev, "failed to parse ddc-i2c-bus\n");
374 return -EPROBE_DEFER;
375 }
376
377 ddata->i2c_adapter = adapter;
378 }
379
380 return 0;
381 }
382
dvic_probe(struct platform_device * pdev)383 static int dvic_probe(struct platform_device *pdev)
384 {
385 struct panel_drv_data *ddata;
386 struct omap_dss_device *dssdev;
387 int r;
388
389 ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
390 if (!ddata)
391 return -ENOMEM;
392
393 platform_set_drvdata(pdev, ddata);
394
395 r = dvic_probe_of(pdev);
396 if (r)
397 return r;
398
399 ddata->vm = dvic_default_vm;
400
401 dssdev = &ddata->dssdev;
402 dssdev->driver = &dvic_driver;
403 dssdev->dev = &pdev->dev;
404 dssdev->type = OMAP_DISPLAY_TYPE_DVI;
405 dssdev->owner = THIS_MODULE;
406 dssdev->panel.vm = dvic_default_vm;
407
408 r = omapdss_register_display(dssdev);
409 if (r) {
410 dev_err(&pdev->dev, "Failed to register panel\n");
411 goto err_reg;
412 }
413
414 return 0;
415
416 err_reg:
417 i2c_put_adapter(ddata->i2c_adapter);
418 mutex_destroy(&ddata->hpd_lock);
419
420 return r;
421 }
422
dvic_remove(struct platform_device * pdev)423 static int __exit dvic_remove(struct platform_device *pdev)
424 {
425 struct panel_drv_data *ddata = platform_get_drvdata(pdev);
426 struct omap_dss_device *dssdev = &ddata->dssdev;
427
428 omapdss_unregister_display(&ddata->dssdev);
429
430 dvic_disable(dssdev);
431 dvic_disconnect(dssdev);
432
433 i2c_put_adapter(ddata->i2c_adapter);
434
435 mutex_destroy(&ddata->hpd_lock);
436
437 return 0;
438 }
439
440 static const struct of_device_id dvic_of_match[] = {
441 { .compatible = "omapdss,dvi-connector", },
442 {},
443 };
444
445 MODULE_DEVICE_TABLE(of, dvic_of_match);
446
447 static struct platform_driver dvi_connector_driver = {
448 .probe = dvic_probe,
449 .remove = __exit_p(dvic_remove),
450 .driver = {
451 .name = "connector-dvi",
452 .of_match_table = dvic_of_match,
453 .suppress_bind_attrs = true,
454 },
455 };
456
457 module_platform_driver(dvi_connector_driver);
458
459 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
460 MODULE_DESCRIPTION("Generic DVI Connector driver");
461 MODULE_LICENSE("GPL");
462