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 const struct drm_edid *drm_edid;
54 int ret;
55
56 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_EDID) {
57 drm_edid = drm_bridge_edid_read(bridge: dvi->next_bridge, connector);
58 if (!drm_edid)
59 DRM_INFO("EDID read failed. Fallback to standard modes\n");
60 } else {
61 drm_edid = NULL;
62 }
63
64 drm_edid_connector_update(connector, edid: drm_edid);
65
66 if (!drm_edid) {
67 /*
68 * No EDID, fallback on the XGA standard modes and prefer a mode
69 * pretty much anything can handle.
70 */
71 ret = drm_add_modes_noedid(connector, hdisplay: 1920, vdisplay: 1200);
72 drm_set_preferred_mode(connector, hpref: 1024, vpref: 768);
73 return ret;
74 }
75
76 ret = drm_edid_connector_add_modes(connector);
77
78 drm_edid_free(drm_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, connector);
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 struct drm_encoder *encoder,
124 enum drm_bridge_attach_flags flags)
125{
126 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
127 int ret;
128
129 ret = drm_bridge_attach(encoder, bridge: dvi->next_bridge, previous: bridge,
130 flags: DRM_BRIDGE_ATTACH_NO_CONNECTOR);
131 if (ret < 0)
132 return ret;
133
134 if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
135 return 0;
136
137 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_DETECT)
138 dvi->connector.polled = DRM_CONNECTOR_POLL_HPD;
139 else
140 dvi->connector.polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT;
141
142 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) {
143 INIT_DELAYED_WORK(&dvi->hpd_work, tfp410_hpd_work_func);
144 drm_bridge_hpd_enable(bridge: dvi->next_bridge, cb: tfp410_hpd_callback,
145 data: dvi);
146 }
147
148 drm_connector_helper_add(connector: &dvi->connector,
149 funcs: &tfp410_con_helper_funcs);
150 ret = drm_connector_init_with_ddc(dev: bridge->dev, connector: &dvi->connector,
151 funcs: &tfp410_con_funcs,
152 connector_type: dvi->next_bridge->type,
153 ddc: dvi->next_bridge->ddc);
154 if (ret) {
155 dev_err(dvi->dev, "drm_connector_init_with_ddc() failed: %d\n",
156 ret);
157 return ret;
158 }
159
160 drm_display_info_set_bus_formats(info: &dvi->connector.display_info,
161 formats: &dvi->bus_format, num_formats: 1);
162
163 drm_connector_attach_encoder(connector: &dvi->connector, encoder);
164
165 return 0;
166}
167
168static void tfp410_detach(struct drm_bridge *bridge)
169{
170 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
171
172 if (dvi->connector.dev && dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) {
173 drm_bridge_hpd_disable(bridge: dvi->next_bridge);
174 cancel_delayed_work_sync(dwork: &dvi->hpd_work);
175 }
176}
177
178static void tfp410_enable(struct drm_bridge *bridge)
179{
180 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
181
182 gpiod_set_value_cansleep(desc: dvi->powerdown, value: 0);
183}
184
185static void tfp410_disable(struct drm_bridge *bridge)
186{
187 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
188
189 gpiod_set_value_cansleep(desc: dvi->powerdown, value: 1);
190}
191
192static enum drm_mode_status tfp410_mode_valid(struct drm_bridge *bridge,
193 const struct drm_display_info *info,
194 const struct drm_display_mode *mode)
195{
196 if (mode->clock < 25000)
197 return MODE_CLOCK_LOW;
198
199 if (mode->clock > 165000)
200 return MODE_CLOCK_HIGH;
201
202 return MODE_OK;
203}
204
205static u32 *tfp410_get_input_bus_fmts(struct drm_bridge *bridge,
206 struct drm_bridge_state *bridge_state,
207 struct drm_crtc_state *crtc_state,
208 struct drm_connector_state *conn_state,
209 u32 output_fmt,
210 unsigned int *num_input_fmts)
211{
212 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
213 u32 *input_fmts;
214
215 *num_input_fmts = 0;
216
217 input_fmts = kzalloc(sizeof(*input_fmts), GFP_KERNEL);
218 if (!input_fmts)
219 return NULL;
220
221 *num_input_fmts = 1;
222 input_fmts[0] = dvi->bus_format;
223
224 return input_fmts;
225}
226
227static int tfp410_atomic_check(struct drm_bridge *bridge,
228 struct drm_bridge_state *bridge_state,
229 struct drm_crtc_state *crtc_state,
230 struct drm_connector_state *conn_state)
231{
232 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
233
234 /*
235 * There might be flags negotiation supported in future.
236 * Set the bus flags in atomic_check statically for now.
237 */
238 bridge_state->input_bus_cfg.flags = dvi->timings.input_bus_flags;
239
240 return 0;
241}
242
243static const struct drm_bridge_funcs tfp410_bridge_funcs = {
244 .attach = tfp410_attach,
245 .detach = tfp410_detach,
246 .enable = tfp410_enable,
247 .disable = tfp410_disable,
248 .mode_valid = tfp410_mode_valid,
249 .atomic_reset = drm_atomic_helper_bridge_reset,
250 .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
251 .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
252 .atomic_get_input_bus_fmts = tfp410_get_input_bus_fmts,
253 .atomic_check = tfp410_atomic_check,
254};
255
256static const struct drm_bridge_timings tfp410_default_timings = {
257 .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
258 | DRM_BUS_FLAG_DE_HIGH,
259 .setup_time_ps = 1200,
260 .hold_time_ps = 1300,
261};
262
263static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c)
264{
265 struct drm_bridge_timings *timings = &dvi->timings;
266 struct device_node *ep;
267 u32 pclk_sample = 0;
268 u32 bus_width = 24;
269 u32 deskew = 0;
270
271 /* Start with defaults. */
272 *timings = tfp410_default_timings;
273
274 if (i2c)
275 /*
276 * In I2C mode timings are configured through the I2C interface.
277 * As the driver doesn't support I2C configuration yet, we just
278 * go with the defaults (BSEL=1, DSEL=1, DKEN=0, EDGE=1).
279 */
280 return 0;
281
282 /*
283 * In non-I2C mode, timings are configured through the BSEL, DSEL, DKEN
284 * and EDGE pins. They are specified in DT through endpoint properties
285 * and vendor-specific properties.
286 */
287 ep = of_graph_get_endpoint_by_regs(parent: dvi->dev->of_node, port_reg: 0, reg: 0);
288 if (!ep)
289 return -EINVAL;
290
291 /* Get the sampling edge from the endpoint. */
292 of_property_read_u32(np: ep, propname: "pclk-sample", out_value: &pclk_sample);
293 of_property_read_u32(np: ep, propname: "bus-width", out_value: &bus_width);
294 of_node_put(node: ep);
295
296 timings->input_bus_flags = DRM_BUS_FLAG_DE_HIGH;
297
298 switch (pclk_sample) {
299 case 0:
300 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE
301 | DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE;
302 break;
303 case 1:
304 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
305 | DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE;
306 break;
307 default:
308 return -EINVAL;
309 }
310
311 switch (bus_width) {
312 case 12:
313 dvi->bus_format = MEDIA_BUS_FMT_RGB888_2X12_LE;
314 break;
315 case 24:
316 dvi->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
317 break;
318 default:
319 return -EINVAL;
320 }
321
322 /* Get the setup and hold time from vendor-specific properties. */
323 of_property_read_u32(np: dvi->dev->of_node, propname: "ti,deskew", out_value: &deskew);
324 if (deskew > 7)
325 return -EINVAL;
326
327 timings->setup_time_ps = 1200 - 350 * ((s32)deskew - 4);
328 timings->hold_time_ps = max(0, 1300 + 350 * ((s32)deskew - 4));
329
330 return 0;
331}
332
333static int tfp410_init(struct device *dev, bool i2c)
334{
335 struct device_node *node;
336 struct tfp410 *dvi;
337 int ret;
338
339 if (!dev->of_node) {
340 dev_err(dev, "device-tree data is missing\n");
341 return -ENXIO;
342 }
343
344 dvi = devm_drm_bridge_alloc(dev, struct tfp410, bridge,
345 &tfp410_bridge_funcs);
346 if (IS_ERR(ptr: dvi))
347 return PTR_ERR(ptr: dvi);
348
349 dvi->dev = dev;
350 dev_set_drvdata(dev, data: dvi);
351
352 dvi->bridge.of_node = dev->of_node;
353 dvi->bridge.timings = &dvi->timings;
354 dvi->bridge.type = DRM_MODE_CONNECTOR_DVID;
355
356 ret = tfp410_parse_timings(dvi, i2c);
357 if (ret)
358 return ret;
359
360 /* Get the next bridge, connected to port@1. */
361 node = of_graph_get_remote_node(node: dev->of_node, port: 1, endpoint: -1);
362 if (!node)
363 return -ENODEV;
364
365 dvi->next_bridge = of_drm_find_bridge(np: node);
366 of_node_put(node);
367
368 if (!dvi->next_bridge)
369 return -EPROBE_DEFER;
370
371 /* Get the powerdown GPIO. */
372 dvi->powerdown = devm_gpiod_get_optional(dev, con_id: "powerdown",
373 flags: GPIOD_OUT_HIGH);
374 if (IS_ERR(ptr: dvi->powerdown)) {
375 dev_err(dev, "failed to parse powerdown gpio\n");
376 return PTR_ERR(ptr: dvi->powerdown);
377 }
378
379 /* Register the DRM bridge. */
380 drm_bridge_add(bridge: &dvi->bridge);
381
382 return 0;
383}
384
385static void tfp410_fini(struct device *dev)
386{
387 struct tfp410 *dvi = dev_get_drvdata(dev);
388
389 drm_bridge_remove(bridge: &dvi->bridge);
390}
391
392static int tfp410_probe(struct platform_device *pdev)
393{
394 return tfp410_init(dev: &pdev->dev, i2c: false);
395}
396
397static void tfp410_remove(struct platform_device *pdev)
398{
399 tfp410_fini(dev: &pdev->dev);
400}
401
402static const struct of_device_id tfp410_match[] = {
403 { .compatible = "ti,tfp410" },
404 {},
405};
406MODULE_DEVICE_TABLE(of, tfp410_match);
407
408static struct platform_driver tfp410_platform_driver = {
409 .probe = tfp410_probe,
410 .remove = tfp410_remove,
411 .driver = {
412 .name = "tfp410-bridge",
413 .of_match_table = tfp410_match,
414 },
415};
416
417#if IS_ENABLED(CONFIG_I2C)
418/* There is currently no i2c functionality. */
419static int tfp410_i2c_probe(struct i2c_client *client)
420{
421 int reg;
422
423 if (!client->dev.of_node ||
424 of_property_read_u32(np: client->dev.of_node, propname: "reg", out_value: &reg)) {
425 dev_err(&client->dev,
426 "Can't get i2c reg property from device-tree\n");
427 return -ENXIO;
428 }
429
430 return tfp410_init(dev: &client->dev, i2c: true);
431}
432
433static void tfp410_i2c_remove(struct i2c_client *client)
434{
435 tfp410_fini(dev: &client->dev);
436}
437
438static const struct i2c_device_id tfp410_i2c_ids[] = {
439 { "tfp410" },
440 { }
441};
442MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids);
443
444static struct i2c_driver tfp410_i2c_driver = {
445 .driver = {
446 .name = "tfp410",
447 .of_match_table = tfp410_match,
448 },
449 .id_table = tfp410_i2c_ids,
450 .probe = tfp410_i2c_probe,
451 .remove = tfp410_i2c_remove,
452};
453#endif /* IS_ENABLED(CONFIG_I2C) */
454
455static struct {
456 uint i2c:1;
457 uint platform:1;
458} tfp410_registered_driver;
459
460static int __init tfp410_module_init(void)
461{
462 int ret;
463
464#if IS_ENABLED(CONFIG_I2C)
465 ret = i2c_add_driver(&tfp410_i2c_driver);
466 if (ret)
467 pr_err("%s: registering i2c driver failed: %d",
468 __func__, ret);
469 else
470 tfp410_registered_driver.i2c = 1;
471#endif
472
473 ret = platform_driver_register(&tfp410_platform_driver);
474 if (ret)
475 pr_err("%s: registering platform driver failed: %d",
476 __func__, ret);
477 else
478 tfp410_registered_driver.platform = 1;
479
480 if (tfp410_registered_driver.i2c ||
481 tfp410_registered_driver.platform)
482 return 0;
483
484 return ret;
485}
486module_init(tfp410_module_init);
487
488static void __exit tfp410_module_exit(void)
489{
490#if IS_ENABLED(CONFIG_I2C)
491 if (tfp410_registered_driver.i2c)
492 i2c_del_driver(driver: &tfp410_i2c_driver);
493#endif
494 if (tfp410_registered_driver.platform)
495 platform_driver_unregister(&tfp410_platform_driver);
496}
497module_exit(tfp410_module_exit);
498
499MODULE_AUTHOR("Jyri Sarha <jsarha@ti.com>");
500MODULE_DESCRIPTION("TI TFP410 DVI bridge driver");
501MODULE_LICENSE("GPL");
502

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