Loading...
Note: File does not exist in v4.6.
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2016 Texas Instruments
4 * Author: Jyri Sarha <jsarha@ti.com>
5 */
6
7#include <linux/gpio/consumer.h>
8#include <linux/i2c.h>
9#include <linux/media-bus-format.h>
10#include <linux/module.h>
11#include <linux/of_graph.h>
12#include <linux/platform_device.h>
13#include <linux/workqueue.h>
14
15#include <drm/drm_atomic_helper.h>
16#include <drm/drm_bridge.h>
17#include <drm/drm_crtc.h>
18#include <drm/drm_edid.h>
19#include <drm/drm_print.h>
20#include <drm/drm_probe_helper.h>
21
22#define HOTPLUG_DEBOUNCE_MS 1100
23
24struct tfp410 {
25 struct drm_bridge bridge;
26 struct drm_connector connector;
27
28 u32 bus_format;
29 struct delayed_work hpd_work;
30 struct gpio_desc *powerdown;
31
32 struct drm_bridge_timings timings;
33 struct drm_bridge *next_bridge;
34
35 struct device *dev;
36};
37
38static inline struct tfp410 *
39drm_bridge_to_tfp410(struct drm_bridge *bridge)
40{
41 return container_of(bridge, struct tfp410, bridge);
42}
43
44static inline struct tfp410 *
45drm_connector_to_tfp410(struct drm_connector *connector)
46{
47 return container_of(connector, struct tfp410, connector);
48}
49
50static 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->next_bridge->ops & DRM_BRIDGE_OP_EDID) {
57 edid = drm_bridge_get_edid(dvi->next_bridge, connector);
58 if (!edid)
59 DRM_INFO("EDID read failed. Fallback to standard modes\n");
60 } else {
61 edid = NULL;
62 }
63
64 if (!edid) {
65 /*
66 * No EDID, fallback on the XGA standard modes and prefer a mode
67 * pretty much anything can handle.
68 */
69 ret = drm_add_modes_noedid(connector, 1920, 1200);
70 drm_set_preferred_mode(connector, 1024, 768);
71 return ret;
72 }
73
74 drm_connector_update_edid_property(connector, edid);
75
76 ret = drm_add_edid_modes(connector, edid);
77
78 kfree(edid);
79
80 return ret;
81}
82
83static const struct drm_connector_helper_funcs tfp410_con_helper_funcs = {
84 .get_modes = tfp410_get_modes,
85};
86
87static enum drm_connector_status
88tfp410_connector_detect(struct drm_connector *connector, bool force)
89{
90 struct tfp410 *dvi = drm_connector_to_tfp410(connector);
91
92 return drm_bridge_detect(dvi->next_bridge);
93}
94
95static const struct drm_connector_funcs tfp410_con_funcs = {
96 .detect = tfp410_connector_detect,
97 .fill_modes = drm_helper_probe_single_connector_modes,
98 .destroy = drm_connector_cleanup,
99 .reset = drm_atomic_helper_connector_reset,
100 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
101 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
102};
103
104static void tfp410_hpd_work_func(struct work_struct *work)
105{
106 struct tfp410 *dvi;
107
108 dvi = container_of(work, struct tfp410, hpd_work.work);
109
110 if (dvi->bridge.dev)
111 drm_helper_hpd_irq_event(dvi->bridge.dev);
112}
113
114static void tfp410_hpd_callback(void *arg, enum drm_connector_status status)
115{
116 struct tfp410 *dvi = arg;
117
118 mod_delayed_work(system_wq, &dvi->hpd_work,
119 msecs_to_jiffies(HOTPLUG_DEBOUNCE_MS));
120}
121
122static int tfp410_attach(struct drm_bridge *bridge,
123 enum drm_bridge_attach_flags flags)
124{
125 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
126 int ret;
127
128 ret = drm_bridge_attach(bridge->encoder, dvi->next_bridge, bridge,
129 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
130 if (ret < 0)
131 return ret;
132
133 if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
134 return 0;
135
136 if (!bridge->encoder) {
137 dev_err(dvi->dev, "Missing encoder\n");
138 return -ENODEV;
139 }
140
141 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_DETECT)
142 dvi->connector.polled = DRM_CONNECTOR_POLL_HPD;
143 else
144 dvi->connector.polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT;
145
146 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) {
147 INIT_DELAYED_WORK(&dvi->hpd_work, tfp410_hpd_work_func);
148 drm_bridge_hpd_enable(dvi->next_bridge, tfp410_hpd_callback,
149 dvi);
150 }
151
152 drm_connector_helper_add(&dvi->connector,
153 &tfp410_con_helper_funcs);
154 ret = drm_connector_init_with_ddc(bridge->dev, &dvi->connector,
155 &tfp410_con_funcs,
156 dvi->next_bridge->type,
157 dvi->next_bridge->ddc);
158 if (ret) {
159 dev_err(dvi->dev, "drm_connector_init_with_ddc() failed: %d\n",
160 ret);
161 return ret;
162 }
163
164 drm_display_info_set_bus_formats(&dvi->connector.display_info,
165 &dvi->bus_format, 1);
166
167 drm_connector_attach_encoder(&dvi->connector, bridge->encoder);
168
169 return 0;
170}
171
172static void tfp410_detach(struct drm_bridge *bridge)
173{
174 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
175
176 if (dvi->connector.dev && dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) {
177 drm_bridge_hpd_disable(dvi->next_bridge);
178 cancel_delayed_work_sync(&dvi->hpd_work);
179 }
180}
181
182static void tfp410_enable(struct drm_bridge *bridge)
183{
184 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
185
186 gpiod_set_value_cansleep(dvi->powerdown, 0);
187}
188
189static void tfp410_disable(struct drm_bridge *bridge)
190{
191 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
192
193 gpiod_set_value_cansleep(dvi->powerdown, 1);
194}
195
196static enum drm_mode_status tfp410_mode_valid(struct drm_bridge *bridge,
197 const struct drm_display_info *info,
198 const struct drm_display_mode *mode)
199{
200 if (mode->clock < 25000)
201 return MODE_CLOCK_LOW;
202
203 if (mode->clock > 165000)
204 return MODE_CLOCK_HIGH;
205
206 return MODE_OK;
207}
208
209static const struct drm_bridge_funcs tfp410_bridge_funcs = {
210 .attach = tfp410_attach,
211 .detach = tfp410_detach,
212 .enable = tfp410_enable,
213 .disable = tfp410_disable,
214 .mode_valid = tfp410_mode_valid,
215};
216
217static const struct drm_bridge_timings tfp410_default_timings = {
218 .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
219 | DRM_BUS_FLAG_DE_HIGH,
220 .setup_time_ps = 1200,
221 .hold_time_ps = 1300,
222};
223
224static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c)
225{
226 struct drm_bridge_timings *timings = &dvi->timings;
227 struct device_node *ep;
228 u32 pclk_sample = 0;
229 u32 bus_width = 24;
230 u32 deskew = 0;
231
232 /* Start with defaults. */
233 *timings = tfp410_default_timings;
234
235 if (i2c)
236 /*
237 * In I2C mode timings are configured through the I2C interface.
238 * As the driver doesn't support I2C configuration yet, we just
239 * go with the defaults (BSEL=1, DSEL=1, DKEN=0, EDGE=1).
240 */
241 return 0;
242
243 /*
244 * In non-I2C mode, timings are configured through the BSEL, DSEL, DKEN
245 * and EDGE pins. They are specified in DT through endpoint properties
246 * and vendor-specific properties.
247 */
248 ep = of_graph_get_endpoint_by_regs(dvi->dev->of_node, 0, 0);
249 if (!ep)
250 return -EINVAL;
251
252 /* Get the sampling edge from the endpoint. */
253 of_property_read_u32(ep, "pclk-sample", &pclk_sample);
254 of_property_read_u32(ep, "bus-width", &bus_width);
255 of_node_put(ep);
256
257 timings->input_bus_flags = DRM_BUS_FLAG_DE_HIGH;
258
259 switch (pclk_sample) {
260 case 0:
261 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE
262 | DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE;
263 break;
264 case 1:
265 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
266 | DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE;
267 break;
268 default:
269 return -EINVAL;
270 }
271
272 switch (bus_width) {
273 case 12:
274 dvi->bus_format = MEDIA_BUS_FMT_RGB888_2X12_LE;
275 break;
276 case 24:
277 dvi->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
278 break;
279 default:
280 return -EINVAL;
281 }
282
283 /* Get the setup and hold time from vendor-specific properties. */
284 of_property_read_u32(dvi->dev->of_node, "ti,deskew", &deskew);
285 if (deskew > 7)
286 return -EINVAL;
287
288 timings->setup_time_ps = 1200 - 350 * ((s32)deskew - 4);
289 timings->hold_time_ps = max(0, 1300 + 350 * ((s32)deskew - 4));
290
291 return 0;
292}
293
294static int tfp410_init(struct device *dev, bool i2c)
295{
296 struct device_node *node;
297 struct tfp410 *dvi;
298 int ret;
299
300 if (!dev->of_node) {
301 dev_err(dev, "device-tree data is missing\n");
302 return -ENXIO;
303 }
304
305 dvi = devm_kzalloc(dev, sizeof(*dvi), GFP_KERNEL);
306 if (!dvi)
307 return -ENOMEM;
308
309 dvi->dev = dev;
310 dev_set_drvdata(dev, dvi);
311
312 dvi->bridge.funcs = &tfp410_bridge_funcs;
313 dvi->bridge.of_node = dev->of_node;
314 dvi->bridge.timings = &dvi->timings;
315 dvi->bridge.type = DRM_MODE_CONNECTOR_DVID;
316
317 ret = tfp410_parse_timings(dvi, i2c);
318 if (ret)
319 return ret;
320
321 /* Get the next bridge, connected to port@1. */
322 node = of_graph_get_remote_node(dev->of_node, 1, -1);
323 if (!node)
324 return -ENODEV;
325
326 dvi->next_bridge = of_drm_find_bridge(node);
327 of_node_put(node);
328
329 if (!dvi->next_bridge)
330 return -EPROBE_DEFER;
331
332 /* Get the powerdown GPIO. */
333 dvi->powerdown = devm_gpiod_get_optional(dev, "powerdown",
334 GPIOD_OUT_HIGH);
335 if (IS_ERR(dvi->powerdown)) {
336 dev_err(dev, "failed to parse powerdown gpio\n");
337 return PTR_ERR(dvi->powerdown);
338 }
339
340 /* Register the DRM bridge. */
341 drm_bridge_add(&dvi->bridge);
342
343 return 0;
344}
345
346static void tfp410_fini(struct device *dev)
347{
348 struct tfp410 *dvi = dev_get_drvdata(dev);
349
350 drm_bridge_remove(&dvi->bridge);
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 tfp410_fini(&pdev->dev);
361
362 return 0;
363}
364
365static const struct of_device_id tfp410_match[] = {
366 { .compatible = "ti,tfp410" },
367 {},
368};
369MODULE_DEVICE_TABLE(of, tfp410_match);
370
371static struct platform_driver tfp410_platform_driver = {
372 .probe = tfp410_probe,
373 .remove = tfp410_remove,
374 .driver = {
375 .name = "tfp410-bridge",
376 .of_match_table = tfp410_match,
377 },
378};
379
380#if IS_ENABLED(CONFIG_I2C)
381/* There is currently no i2c functionality. */
382static int tfp410_i2c_probe(struct i2c_client *client,
383 const struct i2c_device_id *id)
384{
385 int reg;
386
387 if (!client->dev.of_node ||
388 of_property_read_u32(client->dev.of_node, "reg", ®)) {
389 dev_err(&client->dev,
390 "Can't get i2c reg property from device-tree\n");
391 return -ENXIO;
392 }
393
394 return tfp410_init(&client->dev, true);
395}
396
397static void tfp410_i2c_remove(struct i2c_client *client)
398{
399 tfp410_fini(&client->dev);
400}
401
402static const struct i2c_device_id tfp410_i2c_ids[] = {
403 { "tfp410", 0 },
404 { }
405};
406MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids);
407
408static struct i2c_driver tfp410_i2c_driver = {
409 .driver = {
410 .name = "tfp410",
411 .of_match_table = of_match_ptr(tfp410_match),
412 },
413 .id_table = tfp410_i2c_ids,
414 .probe = tfp410_i2c_probe,
415 .remove = tfp410_i2c_remove,
416};
417#endif /* IS_ENABLED(CONFIG_I2C) */
418
419static struct {
420 uint i2c:1;
421 uint platform:1;
422} tfp410_registered_driver;
423
424static int __init tfp410_module_init(void)
425{
426 int ret;
427
428#if IS_ENABLED(CONFIG_I2C)
429 ret = i2c_add_driver(&tfp410_i2c_driver);
430 if (ret)
431 pr_err("%s: registering i2c driver failed: %d",
432 __func__, ret);
433 else
434 tfp410_registered_driver.i2c = 1;
435#endif
436
437 ret = platform_driver_register(&tfp410_platform_driver);
438 if (ret)
439 pr_err("%s: registering platform driver failed: %d",
440 __func__, ret);
441 else
442 tfp410_registered_driver.platform = 1;
443
444 if (tfp410_registered_driver.i2c ||
445 tfp410_registered_driver.platform)
446 return 0;
447
448 return ret;
449}
450module_init(tfp410_module_init);
451
452static void __exit tfp410_module_exit(void)
453{
454#if IS_ENABLED(CONFIG_I2C)
455 if (tfp410_registered_driver.i2c)
456 i2c_del_driver(&tfp410_i2c_driver);
457#endif
458 if (tfp410_registered_driver.platform)
459 platform_driver_unregister(&tfp410_platform_driver);
460}
461module_exit(tfp410_module_exit);
462
463MODULE_AUTHOR("Jyri Sarha <jsarha@ti.com>");
464MODULE_DESCRIPTION("TI TFP410 DVI bridge driver");
465MODULE_LICENSE("GPL");