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(bridge: 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, hdisplay: 1920, vdisplay: 1200);
70 drm_set_preferred_mode(connector, hpref: 1024, vpref: 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(objp: 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(bridge: 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(dev: 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(wq: system_wq, dwork: &dvi->hpd_work,
119 delay: 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(encoder: bridge->encoder, bridge: dvi->next_bridge, previous: bridge,
129 flags: 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(bridge: dvi->next_bridge, cb: tfp410_hpd_callback,
149 data: dvi);
150 }
151
152 drm_connector_helper_add(connector: &dvi->connector,
153 funcs: &tfp410_con_helper_funcs);
154 ret = drm_connector_init_with_ddc(dev: bridge->dev, connector: &dvi->connector,
155 funcs: &tfp410_con_funcs,
156 connector_type: dvi->next_bridge->type,
157 ddc: 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(info: &dvi->connector.display_info,
165 formats: &dvi->bus_format, num_formats: 1);
166
167 drm_connector_attach_encoder(connector: &dvi->connector, encoder: 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(bridge: dvi->next_bridge);
178 cancel_delayed_work_sync(dwork: &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(desc: dvi->powerdown, value: 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(desc: dvi->powerdown, value: 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 u32 *tfp410_get_input_bus_fmts(struct drm_bridge *bridge,
210 struct drm_bridge_state *bridge_state,
211 struct drm_crtc_state *crtc_state,
212 struct drm_connector_state *conn_state,
213 u32 output_fmt,
214 unsigned int *num_input_fmts)
215{
216 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
217 u32 *input_fmts;
218
219 *num_input_fmts = 0;
220
221 input_fmts = kzalloc(size: sizeof(*input_fmts), GFP_KERNEL);
222 if (!input_fmts)
223 return NULL;
224
225 *num_input_fmts = 1;
226 input_fmts[0] = dvi->bus_format;
227
228 return input_fmts;
229}
230
231static int tfp410_atomic_check(struct drm_bridge *bridge,
232 struct drm_bridge_state *bridge_state,
233 struct drm_crtc_state *crtc_state,
234 struct drm_connector_state *conn_state)
235{
236 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
237
238 /*
239 * There might be flags negotiation supported in future.
240 * Set the bus flags in atomic_check statically for now.
241 */
242 bridge_state->input_bus_cfg.flags = dvi->timings.input_bus_flags;
243
244 return 0;
245}
246
247static const struct drm_bridge_funcs tfp410_bridge_funcs = {
248 .attach = tfp410_attach,
249 .detach = tfp410_detach,
250 .enable = tfp410_enable,
251 .disable = tfp410_disable,
252 .mode_valid = tfp410_mode_valid,
253 .atomic_reset = drm_atomic_helper_bridge_reset,
254 .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
255 .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
256 .atomic_get_input_bus_fmts = tfp410_get_input_bus_fmts,
257 .atomic_check = tfp410_atomic_check,
258};
259
260static const struct drm_bridge_timings tfp410_default_timings = {
261 .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
262 | DRM_BUS_FLAG_DE_HIGH,
263 .setup_time_ps = 1200,
264 .hold_time_ps = 1300,
265};
266
267static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c)
268{
269 struct drm_bridge_timings *timings = &dvi->timings;
270 struct device_node *ep;
271 u32 pclk_sample = 0;
272 u32 bus_width = 24;
273 u32 deskew = 0;
274
275 /* Start with defaults. */
276 *timings = tfp410_default_timings;
277
278 if (i2c)
279 /*
280 * In I2C mode timings are configured through the I2C interface.
281 * As the driver doesn't support I2C configuration yet, we just
282 * go with the defaults (BSEL=1, DSEL=1, DKEN=0, EDGE=1).
283 */
284 return 0;
285
286 /*
287 * In non-I2C mode, timings are configured through the BSEL, DSEL, DKEN
288 * and EDGE pins. They are specified in DT through endpoint properties
289 * and vendor-specific properties.
290 */
291 ep = of_graph_get_endpoint_by_regs(parent: dvi->dev->of_node, port_reg: 0, reg: 0);
292 if (!ep)
293 return -EINVAL;
294
295 /* Get the sampling edge from the endpoint. */
296 of_property_read_u32(np: ep, propname: "pclk-sample", out_value: &pclk_sample);
297 of_property_read_u32(np: ep, propname: "bus-width", out_value: &bus_width);
298 of_node_put(node: ep);
299
300 timings->input_bus_flags = DRM_BUS_FLAG_DE_HIGH;
301
302 switch (pclk_sample) {
303 case 0:
304 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE
305 | DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE;
306 break;
307 case 1:
308 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
309 | DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE;
310 break;
311 default:
312 return -EINVAL;
313 }
314
315 switch (bus_width) {
316 case 12:
317 dvi->bus_format = MEDIA_BUS_FMT_RGB888_2X12_LE;
318 break;
319 case 24:
320 dvi->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
321 break;
322 default:
323 return -EINVAL;
324 }
325
326 /* Get the setup and hold time from vendor-specific properties. */
327 of_property_read_u32(np: dvi->dev->of_node, propname: "ti,deskew", out_value: &deskew);
328 if (deskew > 7)
329 return -EINVAL;
330
331 timings->setup_time_ps = 1200 - 350 * ((s32)deskew - 4);
332 timings->hold_time_ps = max(0, 1300 + 350 * ((s32)deskew - 4));
333
334 return 0;
335}
336
337static int tfp410_init(struct device *dev, bool i2c)
338{
339 struct device_node *node;
340 struct tfp410 *dvi;
341 int ret;
342
343 if (!dev->of_node) {
344 dev_err(dev, "device-tree data is missing\n");
345 return -ENXIO;
346 }
347
348 dvi = devm_kzalloc(dev, size: sizeof(*dvi), GFP_KERNEL);
349 if (!dvi)
350 return -ENOMEM;
351
352 dvi->dev = dev;
353 dev_set_drvdata(dev, data: dvi);
354
355 dvi->bridge.funcs = &tfp410_bridge_funcs;
356 dvi->bridge.of_node = dev->of_node;
357 dvi->bridge.timings = &dvi->timings;
358 dvi->bridge.type = DRM_MODE_CONNECTOR_DVID;
359
360 ret = tfp410_parse_timings(dvi, i2c);
361 if (ret)
362 return ret;
363
364 /* Get the next bridge, connected to port@1. */
365 node = of_graph_get_remote_node(node: dev->of_node, port: 1, endpoint: -1);
366 if (!node)
367 return -ENODEV;
368
369 dvi->next_bridge = of_drm_find_bridge(np: node);
370 of_node_put(node);
371
372 if (!dvi->next_bridge)
373 return -EPROBE_DEFER;
374
375 /* Get the powerdown GPIO. */
376 dvi->powerdown = devm_gpiod_get_optional(dev, con_id: "powerdown",
377 flags: GPIOD_OUT_HIGH);
378 if (IS_ERR(ptr: dvi->powerdown)) {
379 dev_err(dev, "failed to parse powerdown gpio\n");
380 return PTR_ERR(ptr: dvi->powerdown);
381 }
382
383 /* Register the DRM bridge. */
384 drm_bridge_add(bridge: &dvi->bridge);
385
386 return 0;
387}
388
389static void tfp410_fini(struct device *dev)
390{
391 struct tfp410 *dvi = dev_get_drvdata(dev);
392
393 drm_bridge_remove(bridge: &dvi->bridge);
394}
395
396static int tfp410_probe(struct platform_device *pdev)
397{
398 return tfp410_init(dev: &pdev->dev, i2c: false);
399}
400
401static void tfp410_remove(struct platform_device *pdev)
402{
403 tfp410_fini(dev: &pdev->dev);
404}
405
406static const struct of_device_id tfp410_match[] = {
407 { .compatible = "ti,tfp410" },
408 {},
409};
410MODULE_DEVICE_TABLE(of, tfp410_match);
411
412static struct platform_driver tfp410_platform_driver = {
413 .probe = tfp410_probe,
414 .remove_new = tfp410_remove,
415 .driver = {
416 .name = "tfp410-bridge",
417 .of_match_table = tfp410_match,
418 },
419};
420
421#if IS_ENABLED(CONFIG_I2C)
422/* There is currently no i2c functionality. */
423static int tfp410_i2c_probe(struct i2c_client *client)
424{
425 int reg;
426
427 if (!client->dev.of_node ||
428 of_property_read_u32(np: client->dev.of_node, propname: "reg", out_value: &reg)) {
429 dev_err(&client->dev,
430 "Can't get i2c reg property from device-tree\n");
431 return -ENXIO;
432 }
433
434 return tfp410_init(dev: &client->dev, i2c: true);
435}
436
437static void tfp410_i2c_remove(struct i2c_client *client)
438{
439 tfp410_fini(dev: &client->dev);
440}
441
442static const struct i2c_device_id tfp410_i2c_ids[] = {
443 { "tfp410", 0 },
444 { }
445};
446MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids);
447
448static struct i2c_driver tfp410_i2c_driver = {
449 .driver = {
450 .name = "tfp410",
451 .of_match_table = tfp410_match,
452 },
453 .id_table = tfp410_i2c_ids,
454 .probe = tfp410_i2c_probe,
455 .remove = tfp410_i2c_remove,
456};
457#endif /* IS_ENABLED(CONFIG_I2C) */
458
459static struct {
460 uint i2c:1;
461 uint platform:1;
462} tfp410_registered_driver;
463
464static int __init tfp410_module_init(void)
465{
466 int ret;
467
468#if IS_ENABLED(CONFIG_I2C)
469 ret = i2c_add_driver(&tfp410_i2c_driver);
470 if (ret)
471 pr_err("%s: registering i2c driver failed: %d",
472 __func__, ret);
473 else
474 tfp410_registered_driver.i2c = 1;
475#endif
476
477 ret = platform_driver_register(&tfp410_platform_driver);
478 if (ret)
479 pr_err("%s: registering platform driver failed: %d",
480 __func__, ret);
481 else
482 tfp410_registered_driver.platform = 1;
483
484 if (tfp410_registered_driver.i2c ||
485 tfp410_registered_driver.platform)
486 return 0;
487
488 return ret;
489}
490module_init(tfp410_module_init);
491
492static void __exit tfp410_module_exit(void)
493{
494#if IS_ENABLED(CONFIG_I2C)
495 if (tfp410_registered_driver.i2c)
496 i2c_del_driver(driver: &tfp410_i2c_driver);
497#endif
498 if (tfp410_registered_driver.platform)
499 platform_driver_unregister(&tfp410_platform_driver);
500}
501module_exit(tfp410_module_exit);
502
503MODULE_AUTHOR("Jyri Sarha <jsarha@ti.com>");
504MODULE_DESCRIPTION("TI TFP410 DVI bridge driver");
505MODULE_LICENSE("GPL");
506

source code of linux/drivers/gpu/drm/bridge/ti-tfp410.c