1 /*
2 * Copyright (C) 2016 Atmel
3 * Bo Shen <voice.shen@atmel.com>
4 *
5 * Authors: Bo Shen <voice.shen@atmel.com>
6 * Boris Brezillon <boris.brezillon@free-electrons.com>
7 * Wu, Songjun <Songjun.Wu@atmel.com>
8 *
9 *
10 * Copyright (C) 2010-2011 Freescale Semiconductor, Inc. All Rights Reserved.
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
21 */
22
23 #include <linux/gpio/consumer.h>
24 #include <linux/i2c.h>
25 #include <linux/module.h>
26 #include <linux/regmap.h>
27
28 #include <drm/drmP.h>
29 #include <drm/drm_atomic_helper.h>
30 #include <drm/drm_crtc_helper.h>
31 #include <drm/drm_edid.h>
32
33 #define SII902X_TPI_VIDEO_DATA 0x0
34
35 #define SII902X_TPI_PIXEL_REPETITION 0x8
36 #define SII902X_TPI_AVI_PIXEL_REP_BUS_24BIT BIT(5)
37 #define SII902X_TPI_AVI_PIXEL_REP_RISING_EDGE BIT(4)
38 #define SII902X_TPI_AVI_PIXEL_REP_4X 3
39 #define SII902X_TPI_AVI_PIXEL_REP_2X 1
40 #define SII902X_TPI_AVI_PIXEL_REP_NONE 0
41 #define SII902X_TPI_CLK_RATIO_HALF (0 << 6)
42 #define SII902X_TPI_CLK_RATIO_1X (1 << 6)
43 #define SII902X_TPI_CLK_RATIO_2X (2 << 6)
44 #define SII902X_TPI_CLK_RATIO_4X (3 << 6)
45
46 #define SII902X_TPI_AVI_IN_FORMAT 0x9
47 #define SII902X_TPI_AVI_INPUT_BITMODE_12BIT BIT(7)
48 #define SII902X_TPI_AVI_INPUT_DITHER BIT(6)
49 #define SII902X_TPI_AVI_INPUT_RANGE_LIMITED (2 << 2)
50 #define SII902X_TPI_AVI_INPUT_RANGE_FULL (1 << 2)
51 #define SII902X_TPI_AVI_INPUT_RANGE_AUTO (0 << 2)
52 #define SII902X_TPI_AVI_INPUT_COLORSPACE_BLACK (3 << 0)
53 #define SII902X_TPI_AVI_INPUT_COLORSPACE_YUV422 (2 << 0)
54 #define SII902X_TPI_AVI_INPUT_COLORSPACE_YUV444 (1 << 0)
55 #define SII902X_TPI_AVI_INPUT_COLORSPACE_RGB (0 << 0)
56
57 #define SII902X_TPI_AVI_INFOFRAME 0x0c
58
59 #define SII902X_SYS_CTRL_DATA 0x1a
60 #define SII902X_SYS_CTRL_PWR_DWN BIT(4)
61 #define SII902X_SYS_CTRL_AV_MUTE BIT(3)
62 #define SII902X_SYS_CTRL_DDC_BUS_REQ BIT(2)
63 #define SII902X_SYS_CTRL_DDC_BUS_GRTD BIT(1)
64 #define SII902X_SYS_CTRL_OUTPUT_MODE BIT(0)
65 #define SII902X_SYS_CTRL_OUTPUT_HDMI 1
66 #define SII902X_SYS_CTRL_OUTPUT_DVI 0
67
68 #define SII902X_REG_CHIPID(n) (0x1b + (n))
69
70 #define SII902X_PWR_STATE_CTRL 0x1e
71 #define SII902X_AVI_POWER_STATE_MSK GENMASK(1, 0)
72 #define SII902X_AVI_POWER_STATE_D(l) ((l) & SII902X_AVI_POWER_STATE_MSK)
73
74 #define SII902X_INT_ENABLE 0x3c
75 #define SII902X_INT_STATUS 0x3d
76 #define SII902X_HOTPLUG_EVENT BIT(0)
77 #define SII902X_PLUGGED_STATUS BIT(2)
78
79 #define SII902X_REG_TPI_RQB 0xc7
80
81 #define SII902X_I2C_BUS_ACQUISITION_TIMEOUT_MS 500
82
83 struct sii902x {
84 struct i2c_client *i2c;
85 struct regmap *regmap;
86 struct drm_bridge bridge;
87 struct drm_connector connector;
88 struct gpio_desc *reset_gpio;
89 };
90
bridge_to_sii902x(struct drm_bridge * bridge)91 static inline struct sii902x *bridge_to_sii902x(struct drm_bridge *bridge)
92 {
93 return container_of(bridge, struct sii902x, bridge);
94 }
95
connector_to_sii902x(struct drm_connector * con)96 static inline struct sii902x *connector_to_sii902x(struct drm_connector *con)
97 {
98 return container_of(con, struct sii902x, connector);
99 }
100
sii902x_reset(struct sii902x * sii902x)101 static void sii902x_reset(struct sii902x *sii902x)
102 {
103 if (!sii902x->reset_gpio)
104 return;
105
106 gpiod_set_value(sii902x->reset_gpio, 1);
107
108 /* The datasheet says treset-min = 100us. Make it 150us to be sure. */
109 usleep_range(150, 200);
110
111 gpiod_set_value(sii902x->reset_gpio, 0);
112 }
113
114 static enum drm_connector_status
sii902x_connector_detect(struct drm_connector * connector,bool force)115 sii902x_connector_detect(struct drm_connector *connector, bool force)
116 {
117 struct sii902x *sii902x = connector_to_sii902x(connector);
118 unsigned int status;
119
120 regmap_read(sii902x->regmap, SII902X_INT_STATUS, &status);
121
122 return (status & SII902X_PLUGGED_STATUS) ?
123 connector_status_connected : connector_status_disconnected;
124 }
125
126 static const struct drm_connector_funcs sii902x_connector_funcs = {
127 .detect = sii902x_connector_detect,
128 .fill_modes = drm_helper_probe_single_connector_modes,
129 .destroy = drm_connector_cleanup,
130 .reset = drm_atomic_helper_connector_reset,
131 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
132 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
133 };
134
sii902x_get_modes(struct drm_connector * connector)135 static int sii902x_get_modes(struct drm_connector *connector)
136 {
137 struct sii902x *sii902x = connector_to_sii902x(connector);
138 struct regmap *regmap = sii902x->regmap;
139 u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
140 struct device *dev = &sii902x->i2c->dev;
141 unsigned long timeout;
142 unsigned int retries;
143 unsigned int status;
144 struct edid *edid;
145 int num = 0;
146 int ret;
147
148 ret = regmap_update_bits(regmap, SII902X_SYS_CTRL_DATA,
149 SII902X_SYS_CTRL_DDC_BUS_REQ,
150 SII902X_SYS_CTRL_DDC_BUS_REQ);
151 if (ret)
152 return ret;
153
154 timeout = jiffies +
155 msecs_to_jiffies(SII902X_I2C_BUS_ACQUISITION_TIMEOUT_MS);
156 do {
157 ret = regmap_read(regmap, SII902X_SYS_CTRL_DATA, &status);
158 if (ret)
159 return ret;
160 } while (!(status & SII902X_SYS_CTRL_DDC_BUS_GRTD) &&
161 time_before(jiffies, timeout));
162
163 if (!(status & SII902X_SYS_CTRL_DDC_BUS_GRTD)) {
164 dev_err(dev, "failed to acquire the i2c bus\n");
165 return -ETIMEDOUT;
166 }
167
168 ret = regmap_write(regmap, SII902X_SYS_CTRL_DATA, status);
169 if (ret)
170 return ret;
171
172 edid = drm_get_edid(connector, sii902x->i2c->adapter);
173 drm_connector_update_edid_property(connector, edid);
174 if (edid) {
175 num = drm_add_edid_modes(connector, edid);
176 kfree(edid);
177 }
178
179 ret = drm_display_info_set_bus_formats(&connector->display_info,
180 &bus_format, 1);
181 if (ret)
182 return ret;
183
184 /*
185 * Sometimes the I2C bus can stall after failure to use the
186 * EDID channel. Retry a few times to see if things clear
187 * up, else continue anyway.
188 */
189 retries = 5;
190 do {
191 ret = regmap_read(regmap, SII902X_SYS_CTRL_DATA,
192 &status);
193 retries--;
194 } while (ret && retries);
195 if (ret)
196 dev_err(dev, "failed to read status (%d)\n", ret);
197
198 ret = regmap_update_bits(regmap, SII902X_SYS_CTRL_DATA,
199 SII902X_SYS_CTRL_DDC_BUS_REQ |
200 SII902X_SYS_CTRL_DDC_BUS_GRTD, 0);
201 if (ret)
202 return ret;
203
204 timeout = jiffies +
205 msecs_to_jiffies(SII902X_I2C_BUS_ACQUISITION_TIMEOUT_MS);
206 do {
207 ret = regmap_read(regmap, SII902X_SYS_CTRL_DATA, &status);
208 if (ret)
209 return ret;
210 } while (status & (SII902X_SYS_CTRL_DDC_BUS_REQ |
211 SII902X_SYS_CTRL_DDC_BUS_GRTD) &&
212 time_before(jiffies, timeout));
213
214 if (status & (SII902X_SYS_CTRL_DDC_BUS_REQ |
215 SII902X_SYS_CTRL_DDC_BUS_GRTD)) {
216 dev_err(dev, "failed to release the i2c bus\n");
217 return -ETIMEDOUT;
218 }
219
220 return num;
221 }
222
sii902x_mode_valid(struct drm_connector * connector,struct drm_display_mode * mode)223 static enum drm_mode_status sii902x_mode_valid(struct drm_connector *connector,
224 struct drm_display_mode *mode)
225 {
226 /* TODO: check mode */
227
228 return MODE_OK;
229 }
230
231 static const struct drm_connector_helper_funcs sii902x_connector_helper_funcs = {
232 .get_modes = sii902x_get_modes,
233 .mode_valid = sii902x_mode_valid,
234 };
235
sii902x_bridge_disable(struct drm_bridge * bridge)236 static void sii902x_bridge_disable(struct drm_bridge *bridge)
237 {
238 struct sii902x *sii902x = bridge_to_sii902x(bridge);
239
240 regmap_update_bits(sii902x->regmap, SII902X_SYS_CTRL_DATA,
241 SII902X_SYS_CTRL_PWR_DWN,
242 SII902X_SYS_CTRL_PWR_DWN);
243 }
244
sii902x_bridge_enable(struct drm_bridge * bridge)245 static void sii902x_bridge_enable(struct drm_bridge *bridge)
246 {
247 struct sii902x *sii902x = bridge_to_sii902x(bridge);
248
249 regmap_update_bits(sii902x->regmap, SII902X_PWR_STATE_CTRL,
250 SII902X_AVI_POWER_STATE_MSK,
251 SII902X_AVI_POWER_STATE_D(0));
252 regmap_update_bits(sii902x->regmap, SII902X_SYS_CTRL_DATA,
253 SII902X_SYS_CTRL_PWR_DWN, 0);
254 }
255
sii902x_bridge_mode_set(struct drm_bridge * bridge,struct drm_display_mode * mode,struct drm_display_mode * adj)256 static void sii902x_bridge_mode_set(struct drm_bridge *bridge,
257 struct drm_display_mode *mode,
258 struct drm_display_mode *adj)
259 {
260 struct sii902x *sii902x = bridge_to_sii902x(bridge);
261 struct regmap *regmap = sii902x->regmap;
262 u8 buf[HDMI_INFOFRAME_SIZE(AVI)];
263 struct hdmi_avi_infoframe frame;
264 u16 pixel_clock_10kHz = adj->clock / 10;
265 int ret;
266
267 buf[0] = pixel_clock_10kHz & 0xff;
268 buf[1] = pixel_clock_10kHz >> 8;
269 buf[2] = adj->vrefresh;
270 buf[3] = 0x00;
271 buf[4] = adj->hdisplay;
272 buf[5] = adj->hdisplay >> 8;
273 buf[6] = adj->vdisplay;
274 buf[7] = adj->vdisplay >> 8;
275 buf[8] = SII902X_TPI_CLK_RATIO_1X | SII902X_TPI_AVI_PIXEL_REP_NONE |
276 SII902X_TPI_AVI_PIXEL_REP_BUS_24BIT;
277 buf[9] = SII902X_TPI_AVI_INPUT_RANGE_AUTO |
278 SII902X_TPI_AVI_INPUT_COLORSPACE_RGB;
279
280 ret = regmap_bulk_write(regmap, SII902X_TPI_VIDEO_DATA, buf, 10);
281 if (ret)
282 return;
283
284 ret = drm_hdmi_avi_infoframe_from_display_mode(&frame, adj, false);
285 if (ret < 0) {
286 DRM_ERROR("couldn't fill AVI infoframe\n");
287 return;
288 }
289
290 ret = hdmi_avi_infoframe_pack(&frame, buf, sizeof(buf));
291 if (ret < 0) {
292 DRM_ERROR("failed to pack AVI infoframe: %d\n", ret);
293 return;
294 }
295
296 /* Do not send the infoframe header, but keep the CRC field. */
297 regmap_bulk_write(regmap, SII902X_TPI_AVI_INFOFRAME,
298 buf + HDMI_INFOFRAME_HEADER_SIZE - 1,
299 HDMI_AVI_INFOFRAME_SIZE + 1);
300 }
301
sii902x_bridge_attach(struct drm_bridge * bridge)302 static int sii902x_bridge_attach(struct drm_bridge *bridge)
303 {
304 struct sii902x *sii902x = bridge_to_sii902x(bridge);
305 struct drm_device *drm = bridge->dev;
306 int ret;
307
308 drm_connector_helper_add(&sii902x->connector,
309 &sii902x_connector_helper_funcs);
310
311 if (!drm_core_check_feature(drm, DRIVER_ATOMIC)) {
312 dev_err(&sii902x->i2c->dev,
313 "sii902x driver is only compatible with DRM devices supporting atomic updates\n");
314 return -ENOTSUPP;
315 }
316
317 ret = drm_connector_init(drm, &sii902x->connector,
318 &sii902x_connector_funcs,
319 DRM_MODE_CONNECTOR_HDMIA);
320 if (ret)
321 return ret;
322
323 if (sii902x->i2c->irq > 0)
324 sii902x->connector.polled = DRM_CONNECTOR_POLL_HPD;
325 else
326 sii902x->connector.polled = DRM_CONNECTOR_POLL_CONNECT;
327
328 drm_connector_attach_encoder(&sii902x->connector, bridge->encoder);
329
330 return 0;
331 }
332
333 static const struct drm_bridge_funcs sii902x_bridge_funcs = {
334 .attach = sii902x_bridge_attach,
335 .mode_set = sii902x_bridge_mode_set,
336 .disable = sii902x_bridge_disable,
337 .enable = sii902x_bridge_enable,
338 };
339
340 static const struct regmap_range sii902x_volatile_ranges[] = {
341 { .range_min = 0, .range_max = 0xff },
342 };
343
344 static const struct regmap_access_table sii902x_volatile_table = {
345 .yes_ranges = sii902x_volatile_ranges,
346 .n_yes_ranges = ARRAY_SIZE(sii902x_volatile_ranges),
347 };
348
349 static const struct regmap_config sii902x_regmap_config = {
350 .reg_bits = 8,
351 .val_bits = 8,
352 .volatile_table = &sii902x_volatile_table,
353 .cache_type = REGCACHE_NONE,
354 };
355
sii902x_interrupt(int irq,void * data)356 static irqreturn_t sii902x_interrupt(int irq, void *data)
357 {
358 struct sii902x *sii902x = data;
359 unsigned int status = 0;
360
361 regmap_read(sii902x->regmap, SII902X_INT_STATUS, &status);
362 regmap_write(sii902x->regmap, SII902X_INT_STATUS, status);
363
364 if ((status & SII902X_HOTPLUG_EVENT) && sii902x->bridge.dev)
365 drm_helper_hpd_irq_event(sii902x->bridge.dev);
366
367 return IRQ_HANDLED;
368 }
369
sii902x_probe(struct i2c_client * client,const struct i2c_device_id * id)370 static int sii902x_probe(struct i2c_client *client,
371 const struct i2c_device_id *id)
372 {
373 struct device *dev = &client->dev;
374 unsigned int status = 0;
375 struct sii902x *sii902x;
376 u8 chipid[4];
377 int ret;
378
379 sii902x = devm_kzalloc(dev, sizeof(*sii902x), GFP_KERNEL);
380 if (!sii902x)
381 return -ENOMEM;
382
383 sii902x->i2c = client;
384 sii902x->regmap = devm_regmap_init_i2c(client, &sii902x_regmap_config);
385 if (IS_ERR(sii902x->regmap))
386 return PTR_ERR(sii902x->regmap);
387
388 sii902x->reset_gpio = devm_gpiod_get_optional(dev, "reset",
389 GPIOD_OUT_LOW);
390 if (IS_ERR(sii902x->reset_gpio)) {
391 dev_err(dev, "Failed to retrieve/request reset gpio: %ld\n",
392 PTR_ERR(sii902x->reset_gpio));
393 return PTR_ERR(sii902x->reset_gpio);
394 }
395
396 sii902x_reset(sii902x);
397
398 ret = regmap_write(sii902x->regmap, SII902X_REG_TPI_RQB, 0x0);
399 if (ret)
400 return ret;
401
402 ret = regmap_bulk_read(sii902x->regmap, SII902X_REG_CHIPID(0),
403 &chipid, 4);
404 if (ret) {
405 dev_err(dev, "regmap_read failed %d\n", ret);
406 return ret;
407 }
408
409 if (chipid[0] != 0xb0) {
410 dev_err(dev, "Invalid chipid: %02x (expecting 0xb0)\n",
411 chipid[0]);
412 return -EINVAL;
413 }
414
415 /* Clear all pending interrupts */
416 regmap_read(sii902x->regmap, SII902X_INT_STATUS, &status);
417 regmap_write(sii902x->regmap, SII902X_INT_STATUS, status);
418
419 if (client->irq > 0) {
420 regmap_write(sii902x->regmap, SII902X_INT_ENABLE,
421 SII902X_HOTPLUG_EVENT);
422
423 ret = devm_request_threaded_irq(dev, client->irq, NULL,
424 sii902x_interrupt,
425 IRQF_ONESHOT, dev_name(dev),
426 sii902x);
427 if (ret)
428 return ret;
429 }
430
431 sii902x->bridge.funcs = &sii902x_bridge_funcs;
432 sii902x->bridge.of_node = dev->of_node;
433 drm_bridge_add(&sii902x->bridge);
434
435 i2c_set_clientdata(client, sii902x);
436
437 return 0;
438 }
439
sii902x_remove(struct i2c_client * client)440 static int sii902x_remove(struct i2c_client *client)
441
442 {
443 struct sii902x *sii902x = i2c_get_clientdata(client);
444
445 drm_bridge_remove(&sii902x->bridge);
446
447 return 0;
448 }
449
450 static const struct of_device_id sii902x_dt_ids[] = {
451 { .compatible = "sil,sii9022", },
452 { }
453 };
454 MODULE_DEVICE_TABLE(of, sii902x_dt_ids);
455
456 static const struct i2c_device_id sii902x_i2c_ids[] = {
457 { "sii9022", 0 },
458 { },
459 };
460 MODULE_DEVICE_TABLE(i2c, sii902x_i2c_ids);
461
462 static struct i2c_driver sii902x_driver = {
463 .probe = sii902x_probe,
464 .remove = sii902x_remove,
465 .driver = {
466 .name = "sii902x",
467 .of_match_table = sii902x_dt_ids,
468 },
469 .id_table = sii902x_i2c_ids,
470 };
471 module_i2c_driver(sii902x_driver);
472
473 MODULE_AUTHOR("Boris Brezillon <boris.brezillon@free-electrons.com>");
474 MODULE_DESCRIPTION("SII902x RGB -> HDMI bridges");
475 MODULE_LICENSE("GPL");
476