summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/bridge/ti-tfp410.c
blob: ba3fa2a9b8a418d04bb54de4a57414861f0ba68a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2016 Texas Instruments
 * Author: Jyri Sarha <jsarha@ti.com>
 */

#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/of_graph.h>
#include <linux/platform_device.h>
#include <linux/workqueue.h>

#include <drm/drm_atomic_helper.h>
#include <drm/drm_bridge.h>
#include <drm/drm_crtc.h>
#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>

#define HOTPLUG_DEBOUNCE_MS		1100

struct tfp410 {
	struct drm_bridge	bridge;
	struct drm_connector	connector;

	u32			bus_format;
	struct delayed_work	hpd_work;
	struct gpio_desc	*powerdown;

	struct drm_bridge_timings timings;
	struct drm_bridge	*next_bridge;

	struct device *dev;
};

static inline struct tfp410 *
drm_bridge_to_tfp410(struct drm_bridge *bridge)
{
	return container_of(bridge, struct tfp410, bridge);
}

static inline struct tfp410 *
drm_connector_to_tfp410(struct drm_connector *connector)
{
	return container_of(connector, struct tfp410, connector);
}

static int tfp410_get_modes(struct drm_connector *connector)
{
	struct tfp410 *dvi = drm_connector_to_tfp410(connector);
	struct edid *edid;
	int ret;

	if (dvi->next_bridge->ops & DRM_BRIDGE_OP_EDID) {
		edid = drm_bridge_get_edid(dvi->next_bridge, connector);
		if (!edid)
			DRM_INFO("EDID read failed. Fallback to standard modes\n");
	} else {
		edid = NULL;
	}

	if (!edid) {
		/*
		 * No EDID, fallback on the XGA standard modes and prefer a mode
		 * pretty much anything can handle.
		 */
		ret = drm_add_modes_noedid(connector, 1920, 1200);
		drm_set_preferred_mode(connector, 1024, 768);
		return ret;
	}

	drm_connector_update_edid_property(connector, edid);

	ret = drm_add_edid_modes(connector, edid);

	kfree(edid);

	return ret;
}

static const struct drm_connector_helper_funcs tfp410_con_helper_funcs = {
	.get_modes	= tfp410_get_modes,
};

static enum drm_connector_status
tfp410_connector_detect(struct drm_connector *connector, bool force)
{
	struct tfp410 *dvi = drm_connector_to_tfp410(connector);

	return drm_bridge_detect(dvi->next_bridge);
}

static const struct drm_connector_funcs tfp410_con_funcs = {
	.detect			= tfp410_connector_detect,
	.fill_modes		= drm_helper_probe_single_connector_modes,
	.destroy		= drm_connector_cleanup,
	.reset			= drm_atomic_helper_connector_reset,
	.atomic_duplicate_state	= drm_atomic_helper_connector_duplicate_state,
	.atomic_destroy_state	= drm_atomic_helper_connector_destroy_state,
};

static void tfp410_hpd_work_func(struct work_struct *work)
{
	struct tfp410 *dvi;

	dvi = container_of(work, struct tfp410, hpd_work.work);

	if (dvi->bridge.dev)
		drm_helper_hpd_irq_event(dvi->bridge.dev);
}

static void tfp410_hpd_callback(void *arg, enum drm_connector_status status)
{
	struct tfp410 *dvi = arg;

	mod_delayed_work(system_wq, &dvi->hpd_work,
			 msecs_to_jiffies(HOTPLUG_DEBOUNCE_MS));
}

static int tfp410_attach(struct drm_bridge *bridge,
			 enum drm_bridge_attach_flags flags)
{
	struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
	int ret;

	ret = drm_bridge_attach(bridge->encoder, dvi->next_bridge, bridge,
				DRM_BRIDGE_ATTACH_NO_CONNECTOR);
	if (ret < 0)
		return ret;

	if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
		return 0;

	if (!bridge->encoder) {
		dev_err(dvi->dev, "Missing encoder\n");
		return -ENODEV;
	}

	if (dvi->next_bridge->ops & DRM_BRIDGE_OP_DETECT)
		dvi->connector.polled = DRM_CONNECTOR_POLL_HPD;
	else
		dvi->connector.polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT;

	if (dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) {
		INIT_DELAYED_WORK(&dvi->hpd_work, tfp410_hpd_work_func);
		drm_bridge_hpd_enable(dvi->next_bridge, tfp410_hpd_callback,
				      dvi);
	}

	drm_connector_helper_add(&dvi->connector,
				 &tfp410_con_helper_funcs);
	ret = drm_connector_init_with_ddc(bridge->dev, &dvi->connector,
					  &tfp410_con_funcs,
					  dvi->next_bridge->type,
					  dvi->next_bridge->ddc);
	if (ret) {
		dev_err(dvi->dev, "drm_connector_init_with_ddc() failed: %d\n",
			ret);
		return ret;
	}

	drm_display_info_set_bus_formats(&dvi->connector.display_info,
					 &dvi->bus_format, 1);

	drm_connector_attach_encoder(&dvi->connector, bridge->encoder);

	return 0;
}

static void tfp410_detach(struct drm_bridge *bridge)
{
	struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);

	if (dvi->connector.dev && dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) {
		drm_bridge_hpd_disable(dvi->next_bridge);
		cancel_delayed_work_sync(&dvi->hpd_work);
	}
}

static void tfp410_enable(struct drm_bridge *bridge)
{
	struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);

	gpiod_set_value_cansleep(dvi->powerdown, 0);
}

static void tfp410_disable(struct drm_bridge *bridge)
{
	struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);

	gpiod_set_value_cansleep(dvi->powerdown, 1);
}

static enum drm_mode_status tfp410_mode_valid(struct drm_bridge *bridge,
					      const struct drm_display_info *info,
					      const struct drm_display_mode *mode)
{
	if (mode->clock < 25000)
		return MODE_CLOCK_LOW;

	if (mode->clock > 165000)
		return MODE_CLOCK_HIGH;

	return MODE_OK;
}

static const struct drm_bridge_funcs tfp410_bridge_funcs = {
	.attach		= tfp410_attach,
	.detach		= tfp410_detach,
	.enable		= tfp410_enable,
	.disable	= tfp410_disable,
	.mode_valid	= tfp410_mode_valid,
};

static const struct drm_bridge_timings tfp410_default_timings = {
	.input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
			 | DRM_BUS_FLAG_DE_HIGH,
	.setup_time_ps = 1200,
	.hold_time_ps = 1300,
};

static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c)
{
	struct drm_bridge_timings *timings = &dvi->timings;
	struct device_node *ep;
	u32 pclk_sample = 0;
	u32 bus_width = 24;
	u32 deskew = 0;

	/* Start with defaults. */
	*timings = tfp410_default_timings;

	if (i2c)
		/*
		 * In I2C mode timings are configured through the I2C interface.
		 * As the driver doesn't support I2C configuration yet, we just
		 * go with the defaults (BSEL=1, DSEL=1, DKEN=0, EDGE=1).
		 */
		return 0;

	/*
	 * In non-I2C mode, timings are configured through the BSEL, DSEL, DKEN
	 * and EDGE pins. They are specified in DT through endpoint properties
	 * and vendor-specific properties.
	 */
	ep = of_graph_get_endpoint_by_regs(dvi->dev->of_node, 0, 0);
	if (!ep)
		return -EINVAL;

	/* Get the sampling edge from the endpoint. */
	of_property_read_u32(ep, "pclk-sample", &pclk_sample);
	of_property_read_u32(ep, "bus-width", &bus_width);
	of_node_put(ep);

	timings->input_bus_flags = DRM_BUS_FLAG_DE_HIGH;

	switch (pclk_sample) {
	case 0:
		timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE
					 |  DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE;
		break;
	case 1:
		timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
					 |  DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE;
		break;
	default:
		return -EINVAL;
	}

	switch (bus_width) {
	case 12:
		dvi->bus_format = MEDIA_BUS_FMT_RGB888_2X12_LE;
		break;
	case 24:
		dvi->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
		break;
	default:
		return -EINVAL;
	}

	/* Get the setup and hold time from vendor-specific properties. */
	of_property_read_u32(dvi->dev->of_node, "ti,deskew", &deskew);
	if (deskew > 7)
		return -EINVAL;

	timings->setup_time_ps = 1200 - 350 * ((s32)deskew - 4);
	timings->hold_time_ps = max(0, 1300 + 350 * ((s32)deskew - 4));

	return 0;
}

static int tfp410_init(struct device *dev, bool i2c)
{
	struct device_node *node;
	struct tfp410 *dvi;
	int ret;

	if (!dev->of_node) {
		dev_err(dev, "device-tree data is missing\n");
		return -ENXIO;
	}

	dvi = devm_kzalloc(dev, sizeof(*dvi), GFP_KERNEL);
	if (!dvi)
		return -ENOMEM;

	dvi->dev = dev;
	dev_set_drvdata(dev, dvi);

	dvi->bridge.funcs = &tfp410_bridge_funcs;
	dvi->bridge.of_node = dev->of_node;
	dvi->bridge.timings = &dvi->timings;
	dvi->bridge.type = DRM_MODE_CONNECTOR_DVID;

	ret = tfp410_parse_timings(dvi, i2c);
	if (ret)
		return ret;

	/* Get the next bridge, connected to port@1. */
	node = of_graph_get_remote_node(dev->of_node, 1, -1);
	if (!node)
		return -ENODEV;

	dvi->next_bridge = of_drm_find_bridge(node);
	of_node_put(node);

	if (!dvi->next_bridge)
		return -EPROBE_DEFER;

	/* Get the powerdown GPIO. */
	dvi->powerdown = devm_gpiod_get_optional(dev, "powerdown",
						 GPIOD_OUT_HIGH);
	if (IS_ERR(dvi->powerdown)) {
		dev_err(dev, "failed to parse powerdown gpio\n");
		return PTR_ERR(dvi->powerdown);
	}

	/*  Register the DRM bridge. */
	drm_bridge_add(&dvi->bridge);

	return 0;
}

static int tfp410_fini(struct device *dev)
{
	struct tfp410 *dvi = dev_get_drvdata(dev);

	drm_bridge_remove(&dvi->bridge);

	return 0;
}

static int tfp410_probe(struct platform_device *pdev)
{
	return tfp410_init(&pdev->dev, false);
}

static int tfp410_remove(struct platform_device *pdev)
{
	return tfp410_fini(&pdev->dev);
}

static const struct of_device_id tfp410_match[] = {
	{ .compatible = "ti,tfp410" },
	{},
};
MODULE_DEVICE_TABLE(of, tfp410_match);

static struct platform_driver tfp410_platform_driver = {
	.probe	= tfp410_probe,
	.remove	= tfp410_remove,
	.driver	= {
		.name		= "tfp410-bridge",
		.of_match_table	= tfp410_match,
	},
};

#if IS_ENABLED(CONFIG_I2C)
/* There is currently no i2c functionality. */
static int tfp410_i2c_probe(struct i2c_client *client,
			    const struct i2c_device_id *id)
{
	int reg;

	if (!client->dev.of_node ||
	    of_property_read_u32(client->dev.of_node, "reg", &reg)) {
		dev_err(&client->dev,
			"Can't get i2c reg property from device-tree\n");
		return -ENXIO;
	}

	return tfp410_init(&client->dev, true);
}

static int tfp410_i2c_remove(struct i2c_client *client)
{
	return tfp410_fini(&client->dev);
}

static const struct i2c_device_id tfp410_i2c_ids[] = {
	{ "tfp410", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids);

static struct i2c_driver tfp410_i2c_driver = {
	.driver = {
		.name	= "tfp410",
		.of_match_table = of_match_ptr(tfp410_match),
	},
	.id_table	= tfp410_i2c_ids,
	.probe		= tfp410_i2c_probe,
	.remove		= tfp410_i2c_remove,
};
#endif /* IS_ENABLED(CONFIG_I2C) */

static struct {
	uint i2c:1;
	uint platform:1;
}  tfp410_registered_driver;

static int __init tfp410_module_init(void)
{
	int ret;

#if IS_ENABLED(CONFIG_I2C)
	ret = i2c_add_driver(&tfp410_i2c_driver);
	if (ret)
		pr_err("%s: registering i2c driver failed: %d",
		       __func__, ret);
	else
		tfp410_registered_driver.i2c = 1;
#endif

	ret = platform_driver_register(&tfp410_platform_driver);
	if (ret)
		pr_err("%s: registering platform driver failed: %d",
		       __func__, ret);
	else
		tfp410_registered_driver.platform = 1;

	if (tfp410_registered_driver.i2c ||
	    tfp410_registered_driver.platform)
		return 0;

	return ret;
}
module_init(tfp410_module_init);

static void __exit tfp410_module_exit(void)
{
#if IS_ENABLED(CONFIG_I2C)
	if (tfp410_registered_driver.i2c)
		i2c_del_driver(&tfp410_i2c_driver);
#endif
	if (tfp410_registered_driver.platform)
		platform_driver_unregister(&tfp410_platform_driver);
}
module_exit(tfp410_module_exit);

MODULE_AUTHOR("Jyri Sarha <jsarha@ti.com>");
MODULE_DESCRIPTION("TI TFP410 DVI bridge driver");
MODULE_LICENSE("GPL");