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7#include <linux/gpio/consumer.h>
8#include <linux/i2c.h>
9#include <linux/module.h>
10#include <linux/of_graph.h>
11#include <linux/platform_device.h>
12#include <linux/workqueue.h>
13
14#include <drm/drm_atomic_helper.h>
15#include <drm/drm_bridge.h>
16#include <drm/drm_crtc.h>
17#include <drm/drm_print.h>
18#include <drm/drm_probe_helper.h>
19
20#define HOTPLUG_DEBOUNCE_MS 1100
21
22struct tfp410 {
23 struct drm_bridge bridge;
24 struct drm_connector connector;
25
26 u32 bus_format;
27 struct delayed_work hpd_work;
28 struct gpio_desc *powerdown;
29
30 struct drm_bridge_timings timings;
31 struct drm_bridge *next_bridge;
32
33 struct device *dev;
34};
35
36static inline struct tfp410 *
37drm_bridge_to_tfp410(struct drm_bridge *bridge)
38{
39 return container_of(bridge, struct tfp410, bridge);
40}
41
42static inline struct tfp410 *
43drm_connector_to_tfp410(struct drm_connector *connector)
44{
45 return container_of(connector, struct tfp410, connector);
46}
47
48static int tfp410_get_modes(struct drm_connector *connector)
49{
50 struct tfp410 *dvi = drm_connector_to_tfp410(connector);
51 struct edid *edid;
52 int ret;
53
54 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_EDID) {
55 edid = drm_bridge_get_edid(dvi->next_bridge, connector);
56 if (!edid)
57 DRM_INFO("EDID read failed. Fallback to standard modes\n");
58 } else {
59 edid = NULL;
60 }
61
62 if (!edid) {
63
64
65
66
67 ret = drm_add_modes_noedid(connector, 1920, 1200);
68 drm_set_preferred_mode(connector, 1024, 768);
69 return ret;
70 }
71
72 drm_connector_update_edid_property(connector, edid);
73
74 ret = drm_add_edid_modes(connector, edid);
75
76 kfree(edid);
77
78 return ret;
79}
80
81static const struct drm_connector_helper_funcs tfp410_con_helper_funcs = {
82 .get_modes = tfp410_get_modes,
83};
84
85static enum drm_connector_status
86tfp410_connector_detect(struct drm_connector *connector, bool force)
87{
88 struct tfp410 *dvi = drm_connector_to_tfp410(connector);
89
90 return drm_bridge_detect(dvi->next_bridge);
91}
92
93static const struct drm_connector_funcs tfp410_con_funcs = {
94 .detect = tfp410_connector_detect,
95 .fill_modes = drm_helper_probe_single_connector_modes,
96 .destroy = drm_connector_cleanup,
97 .reset = drm_atomic_helper_connector_reset,
98 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
99 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
100};
101
102static void tfp410_hpd_work_func(struct work_struct *work)
103{
104 struct tfp410 *dvi;
105
106 dvi = container_of(work, struct tfp410, hpd_work.work);
107
108 if (dvi->bridge.dev)
109 drm_helper_hpd_irq_event(dvi->bridge.dev);
110}
111
112static void tfp410_hpd_callback(void *arg, enum drm_connector_status status)
113{
114 struct tfp410 *dvi = arg;
115
116 mod_delayed_work(system_wq, &dvi->hpd_work,
117 msecs_to_jiffies(HOTPLUG_DEBOUNCE_MS));
118}
119
120static int tfp410_attach(struct drm_bridge *bridge,
121 enum drm_bridge_attach_flags flags)
122{
123 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
124 int ret;
125
126 ret = drm_bridge_attach(bridge->encoder, dvi->next_bridge, bridge,
127 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
128 if (ret < 0)
129 return ret;
130
131 if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
132 return 0;
133
134 if (!bridge->encoder) {
135 dev_err(dvi->dev, "Missing encoder\n");
136 return -ENODEV;
137 }
138
139 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_DETECT)
140 dvi->connector.polled = DRM_CONNECTOR_POLL_HPD;
141 else
142 dvi->connector.polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT;
143
144 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) {
145 INIT_DELAYED_WORK(&dvi->hpd_work, tfp410_hpd_work_func);
146 drm_bridge_hpd_enable(dvi->next_bridge, tfp410_hpd_callback,
147 dvi);
148 }
149
150 drm_connector_helper_add(&dvi->connector,
151 &tfp410_con_helper_funcs);
152 ret = drm_connector_init_with_ddc(bridge->dev, &dvi->connector,
153 &tfp410_con_funcs,
154 dvi->next_bridge->type,
155 dvi->next_bridge->ddc);
156 if (ret) {
157 dev_err(dvi->dev, "drm_connector_init_with_ddc() failed: %d\n",
158 ret);
159 return ret;
160 }
161
162 drm_display_info_set_bus_formats(&dvi->connector.display_info,
163 &dvi->bus_format, 1);
164
165 drm_connector_attach_encoder(&dvi->connector, bridge->encoder);
166
167 return 0;
168}
169
170static void tfp410_detach(struct drm_bridge *bridge)
171{
172 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
173
174 if (dvi->connector.dev && dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) {
175 drm_bridge_hpd_disable(dvi->next_bridge);
176 cancel_delayed_work_sync(&dvi->hpd_work);
177 }
178}
179
180static void tfp410_enable(struct drm_bridge *bridge)
181{
182 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
183
184 gpiod_set_value_cansleep(dvi->powerdown, 0);
185}
186
187static void tfp410_disable(struct drm_bridge *bridge)
188{
189 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
190
191 gpiod_set_value_cansleep(dvi->powerdown, 1);
192}
193
194static enum drm_mode_status tfp410_mode_valid(struct drm_bridge *bridge,
195 const struct drm_display_info *info,
196 const struct drm_display_mode *mode)
197{
198 if (mode->clock < 25000)
199 return MODE_CLOCK_LOW;
200
201 if (mode->clock > 165000)
202 return MODE_CLOCK_HIGH;
203
204 return MODE_OK;
205}
206
207static const struct drm_bridge_funcs tfp410_bridge_funcs = {
208 .attach = tfp410_attach,
209 .detach = tfp410_detach,
210 .enable = tfp410_enable,
211 .disable = tfp410_disable,
212 .mode_valid = tfp410_mode_valid,
213};
214
215static const struct drm_bridge_timings tfp410_default_timings = {
216 .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
217 | DRM_BUS_FLAG_DE_HIGH,
218 .setup_time_ps = 1200,
219 .hold_time_ps = 1300,
220};
221
222static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c)
223{
224 struct drm_bridge_timings *timings = &dvi->timings;
225 struct device_node *ep;
226 u32 pclk_sample = 0;
227 u32 bus_width = 24;
228 u32 deskew = 0;
229
230
231 *timings = tfp410_default_timings;
232
233 if (i2c)
234
235
236
237
238
239 return 0;
240
241
242
243
244
245
246 ep = of_graph_get_endpoint_by_regs(dvi->dev->of_node, 0, 0);
247 if (!ep)
248 return -EINVAL;
249
250
251 of_property_read_u32(ep, "pclk-sample", &pclk_sample);
252 of_property_read_u32(ep, "bus-width", &bus_width);
253 of_node_put(ep);
254
255 timings->input_bus_flags = DRM_BUS_FLAG_DE_HIGH;
256
257 switch (pclk_sample) {
258 case 0:
259 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE
260 | DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE;
261 break;
262 case 1:
263 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
264 | DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE;
265 break;
266 default:
267 return -EINVAL;
268 }
269
270 switch (bus_width) {
271 case 12:
272 dvi->bus_format = MEDIA_BUS_FMT_RGB888_2X12_LE;
273 break;
274 case 24:
275 dvi->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
276 break;
277 default:
278 return -EINVAL;
279 }
280
281
282 of_property_read_u32(dvi->dev->of_node, "ti,deskew", &deskew);
283 if (deskew > 7)
284 return -EINVAL;
285
286 timings->setup_time_ps = 1200 - 350 * ((s32)deskew - 4);
287 timings->hold_time_ps = max(0, 1300 + 350 * ((s32)deskew - 4));
288
289 return 0;
290}
291
292static int tfp410_init(struct device *dev, bool i2c)
293{
294 struct device_node *node;
295 struct tfp410 *dvi;
296 int ret;
297
298 if (!dev->of_node) {
299 dev_err(dev, "device-tree data is missing\n");
300 return -ENXIO;
301 }
302
303 dvi = devm_kzalloc(dev, sizeof(*dvi), GFP_KERNEL);
304 if (!dvi)
305 return -ENOMEM;
306
307 dvi->dev = dev;
308 dev_set_drvdata(dev, dvi);
309
310 dvi->bridge.funcs = &tfp410_bridge_funcs;
311 dvi->bridge.of_node = dev->of_node;
312 dvi->bridge.timings = &dvi->timings;
313 dvi->bridge.type = DRM_MODE_CONNECTOR_DVID;
314
315 ret = tfp410_parse_timings(dvi, i2c);
316 if (ret)
317 return ret;
318
319
320 node = of_graph_get_remote_node(dev->of_node, 1, -1);
321 if (!node)
322 return -ENODEV;
323
324 dvi->next_bridge = of_drm_find_bridge(node);
325 of_node_put(node);
326
327 if (!dvi->next_bridge)
328 return -EPROBE_DEFER;
329
330
331 dvi->powerdown = devm_gpiod_get_optional(dev, "powerdown",
332 GPIOD_OUT_HIGH);
333 if (IS_ERR(dvi->powerdown)) {
334 dev_err(dev, "failed to parse powerdown gpio\n");
335 return PTR_ERR(dvi->powerdown);
336 }
337
338
339 drm_bridge_add(&dvi->bridge);
340
341 return 0;
342}
343
344static int tfp410_fini(struct device *dev)
345{
346 struct tfp410 *dvi = dev_get_drvdata(dev);
347
348 drm_bridge_remove(&dvi->bridge);
349
350 return 0;
351}
352
353static int tfp410_probe(struct platform_device *pdev)
354{
355 return tfp410_init(&pdev->dev, false);
356}
357
358static int tfp410_remove(struct platform_device *pdev)
359{
360 return tfp410_fini(&pdev->dev);
361}
362
363static const struct of_device_id tfp410_match[] = {
364 { .compatible = "ti,tfp410" },
365 {},
366};
367MODULE_DEVICE_TABLE(of, tfp410_match);
368
369static struct platform_driver tfp410_platform_driver = {
370 .probe = tfp410_probe,
371 .remove = tfp410_remove,
372 .driver = {
373 .name = "tfp410-bridge",
374 .of_match_table = tfp410_match,
375 },
376};
377
378#if IS_ENABLED(CONFIG_I2C)
379
380static int tfp410_i2c_probe(struct i2c_client *client,
381 const struct i2c_device_id *id)
382{
383 int reg;
384
385 if (!client->dev.of_node ||
386 of_property_read_u32(client->dev.of_node, "reg", ®)) {
387 dev_err(&client->dev,
388 "Can't get i2c reg property from device-tree\n");
389 return -ENXIO;
390 }
391
392 return tfp410_init(&client->dev, true);
393}
394
395static int tfp410_i2c_remove(struct i2c_client *client)
396{
397 return tfp410_fini(&client->dev);
398}
399
400static const struct i2c_device_id tfp410_i2c_ids[] = {
401 { "tfp410", 0 },
402 { }
403};
404MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids);
405
406static struct i2c_driver tfp410_i2c_driver = {
407 .driver = {
408 .name = "tfp410",
409 .of_match_table = of_match_ptr(tfp410_match),
410 },
411 .id_table = tfp410_i2c_ids,
412 .probe = tfp410_i2c_probe,
413 .remove = tfp410_i2c_remove,
414};
415#endif
416
417static struct {
418 uint i2c:1;
419 uint platform:1;
420} tfp410_registered_driver;
421
422static int __init tfp410_module_init(void)
423{
424 int ret;
425
426#if IS_ENABLED(CONFIG_I2C)
427 ret = i2c_add_driver(&tfp410_i2c_driver);
428 if (ret)
429 pr_err("%s: registering i2c driver failed: %d",
430 __func__, ret);
431 else
432 tfp410_registered_driver.i2c = 1;
433#endif
434
435 ret = platform_driver_register(&tfp410_platform_driver);
436 if (ret)
437 pr_err("%s: registering platform driver failed: %d",
438 __func__, ret);
439 else
440 tfp410_registered_driver.platform = 1;
441
442 if (tfp410_registered_driver.i2c ||
443 tfp410_registered_driver.platform)
444 return 0;
445
446 return ret;
447}
448module_init(tfp410_module_init);
449
450static void __exit tfp410_module_exit(void)
451{
452#if IS_ENABLED(CONFIG_I2C)
453 if (tfp410_registered_driver.i2c)
454 i2c_del_driver(&tfp410_i2c_driver);
455#endif
456 if (tfp410_registered_driver.platform)
457 platform_driver_unregister(&tfp410_platform_driver);
458}
459module_exit(tfp410_module_exit);
460
461MODULE_AUTHOR("Jyri Sarha <jsarha@ti.com>");
462MODULE_DESCRIPTION("TI TFP410 DVI bridge driver");
463MODULE_LICENSE("GPL");
464
