xref: /openbmc/linux/drivers/gpu/drm/bridge/sii902x.c (revision 0c874100)
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 
91 static inline struct sii902x *bridge_to_sii902x(struct drm_bridge *bridge)
92 {
93 	return container_of(bridge, struct sii902x, bridge);
94 }
95 
96 static inline struct sii902x *connector_to_sii902x(struct drm_connector *con)
97 {
98 	return container_of(con, struct sii902x, connector);
99 }
100 
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
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 
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 
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 
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 
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 
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 	int ret;
265 
266 	buf[0] = adj->clock;
267 	buf[1] = adj->clock >> 8;
268 	buf[2] = adj->vrefresh;
269 	buf[3] = 0x00;
270 	buf[4] = adj->hdisplay;
271 	buf[5] = adj->hdisplay >> 8;
272 	buf[6] = adj->vdisplay;
273 	buf[7] = adj->vdisplay >> 8;
274 	buf[8] = SII902X_TPI_CLK_RATIO_1X | SII902X_TPI_AVI_PIXEL_REP_NONE |
275 		 SII902X_TPI_AVI_PIXEL_REP_BUS_24BIT;
276 	buf[9] = SII902X_TPI_AVI_INPUT_RANGE_AUTO |
277 		 SII902X_TPI_AVI_INPUT_COLORSPACE_RGB;
278 
279 	ret = regmap_bulk_write(regmap, SII902X_TPI_VIDEO_DATA, buf, 10);
280 	if (ret)
281 		return;
282 
283 	ret = drm_hdmi_avi_infoframe_from_display_mode(&frame, adj, false);
284 	if (ret < 0) {
285 		DRM_ERROR("couldn't fill AVI infoframe\n");
286 		return;
287 	}
288 
289 	ret = hdmi_avi_infoframe_pack(&frame, buf, sizeof(buf));
290 	if (ret < 0) {
291 		DRM_ERROR("failed to pack AVI infoframe: %d\n", ret);
292 		return;
293 	}
294 
295 	/* Do not send the infoframe header, but keep the CRC field. */
296 	regmap_bulk_write(regmap, SII902X_TPI_AVI_INFOFRAME,
297 			  buf + HDMI_INFOFRAME_HEADER_SIZE - 1,
298 			  HDMI_AVI_INFOFRAME_SIZE + 1);
299 }
300 
301 static int sii902x_bridge_attach(struct drm_bridge *bridge)
302 {
303 	struct sii902x *sii902x = bridge_to_sii902x(bridge);
304 	struct drm_device *drm = bridge->dev;
305 	int ret;
306 
307 	drm_connector_helper_add(&sii902x->connector,
308 				 &sii902x_connector_helper_funcs);
309 
310 	if (!drm_core_check_feature(drm, DRIVER_ATOMIC)) {
311 		dev_err(&sii902x->i2c->dev,
312 			"sii902x driver is only compatible with DRM devices supporting atomic updates\n");
313 		return -ENOTSUPP;
314 	}
315 
316 	ret = drm_connector_init(drm, &sii902x->connector,
317 				 &sii902x_connector_funcs,
318 				 DRM_MODE_CONNECTOR_HDMIA);
319 	if (ret)
320 		return ret;
321 
322 	if (sii902x->i2c->irq > 0)
323 		sii902x->connector.polled = DRM_CONNECTOR_POLL_HPD;
324 	else
325 		sii902x->connector.polled = DRM_CONNECTOR_POLL_CONNECT;
326 
327 	drm_connector_attach_encoder(&sii902x->connector, bridge->encoder);
328 
329 	return 0;
330 }
331 
332 static const struct drm_bridge_funcs sii902x_bridge_funcs = {
333 	.attach = sii902x_bridge_attach,
334 	.mode_set = sii902x_bridge_mode_set,
335 	.disable = sii902x_bridge_disable,
336 	.enable = sii902x_bridge_enable,
337 };
338 
339 static const struct regmap_range sii902x_volatile_ranges[] = {
340 	{ .range_min = 0, .range_max = 0xff },
341 };
342 
343 static const struct regmap_access_table sii902x_volatile_table = {
344 	.yes_ranges = sii902x_volatile_ranges,
345 	.n_yes_ranges = ARRAY_SIZE(sii902x_volatile_ranges),
346 };
347 
348 static const struct regmap_config sii902x_regmap_config = {
349 	.reg_bits = 8,
350 	.val_bits = 8,
351 	.volatile_table = &sii902x_volatile_table,
352 	.cache_type = REGCACHE_NONE,
353 };
354 
355 static irqreturn_t sii902x_interrupt(int irq, void *data)
356 {
357 	struct sii902x *sii902x = data;
358 	unsigned int status = 0;
359 
360 	regmap_read(sii902x->regmap, SII902X_INT_STATUS, &status);
361 	regmap_write(sii902x->regmap, SII902X_INT_STATUS, status);
362 
363 	if ((status & SII902X_HOTPLUG_EVENT) && sii902x->bridge.dev)
364 		drm_helper_hpd_irq_event(sii902x->bridge.dev);
365 
366 	return IRQ_HANDLED;
367 }
368 
369 static int sii902x_probe(struct i2c_client *client,
370 			 const struct i2c_device_id *id)
371 {
372 	struct device *dev = &client->dev;
373 	unsigned int status = 0;
374 	struct sii902x *sii902x;
375 	u8 chipid[4];
376 	int ret;
377 
378 	sii902x = devm_kzalloc(dev, sizeof(*sii902x), GFP_KERNEL);
379 	if (!sii902x)
380 		return -ENOMEM;
381 
382 	sii902x->i2c = client;
383 	sii902x->regmap = devm_regmap_init_i2c(client, &sii902x_regmap_config);
384 	if (IS_ERR(sii902x->regmap))
385 		return PTR_ERR(sii902x->regmap);
386 
387 	sii902x->reset_gpio = devm_gpiod_get_optional(dev, "reset",
388 						      GPIOD_OUT_LOW);
389 	if (IS_ERR(sii902x->reset_gpio)) {
390 		dev_err(dev, "Failed to retrieve/request reset gpio: %ld\n",
391 			PTR_ERR(sii902x->reset_gpio));
392 		return PTR_ERR(sii902x->reset_gpio);
393 	}
394 
395 	sii902x_reset(sii902x);
396 
397 	ret = regmap_write(sii902x->regmap, SII902X_REG_TPI_RQB, 0x0);
398 	if (ret)
399 		return ret;
400 
401 	ret = regmap_bulk_read(sii902x->regmap, SII902X_REG_CHIPID(0),
402 			       &chipid, 4);
403 	if (ret) {
404 		dev_err(dev, "regmap_read failed %d\n", ret);
405 		return ret;
406 	}
407 
408 	if (chipid[0] != 0xb0) {
409 		dev_err(dev, "Invalid chipid: %02x (expecting 0xb0)\n",
410 			chipid[0]);
411 		return -EINVAL;
412 	}
413 
414 	/* Clear all pending interrupts */
415 	regmap_read(sii902x->regmap, SII902X_INT_STATUS, &status);
416 	regmap_write(sii902x->regmap, SII902X_INT_STATUS, status);
417 
418 	if (client->irq > 0) {
419 		regmap_write(sii902x->regmap, SII902X_INT_ENABLE,
420 			     SII902X_HOTPLUG_EVENT);
421 
422 		ret = devm_request_threaded_irq(dev, client->irq, NULL,
423 						sii902x_interrupt,
424 						IRQF_ONESHOT, dev_name(dev),
425 						sii902x);
426 		if (ret)
427 			return ret;
428 	}
429 
430 	sii902x->bridge.funcs = &sii902x_bridge_funcs;
431 	sii902x->bridge.of_node = dev->of_node;
432 	drm_bridge_add(&sii902x->bridge);
433 
434 	i2c_set_clientdata(client, sii902x);
435 
436 	return 0;
437 }
438 
439 static int sii902x_remove(struct i2c_client *client)
440 
441 {
442 	struct sii902x *sii902x = i2c_get_clientdata(client);
443 
444 	drm_bridge_remove(&sii902x->bridge);
445 
446 	return 0;
447 }
448 
449 static const struct of_device_id sii902x_dt_ids[] = {
450 	{ .compatible = "sil,sii9022", },
451 	{ }
452 };
453 MODULE_DEVICE_TABLE(of, sii902x_dt_ids);
454 
455 static const struct i2c_device_id sii902x_i2c_ids[] = {
456 	{ "sii9022", 0 },
457 	{ },
458 };
459 MODULE_DEVICE_TABLE(i2c, sii902x_i2c_ids);
460 
461 static struct i2c_driver sii902x_driver = {
462 	.probe = sii902x_probe,
463 	.remove = sii902x_remove,
464 	.driver = {
465 		.name = "sii902x",
466 		.of_match_table = sii902x_dt_ids,
467 	},
468 	.id_table = sii902x_i2c_ids,
469 };
470 module_i2c_driver(sii902x_driver);
471 
472 MODULE_AUTHOR("Boris Brezillon <boris.brezillon@free-electrons.com>");
473 MODULE_DESCRIPTION("SII902x RGB -> HDMI bridges");
474 MODULE_LICENSE("GPL");
475