xref: /linux/drivers/media/i2c/st-mipid02.c (revision acbf6de674ef7b1b5870b25e7b3c695bf84273d0)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for ST MIPID02 CSI-2 to PARALLEL bridge
4  *
5  * Copyright (C) STMicroelectronics SA 2019
6  * Authors: Mickael Guene <mickael.guene@st.com>
7  *          for STMicroelectronics.
8  *
9  *
10  */
11 
12 #include <linux/clk.h>
13 #include <linux/delay.h>
14 #include <linux/gpio/consumer.h>
15 #include <linux/i2c.h>
16 #include <linux/module.h>
17 #include <linux/of_graph.h>
18 #include <linux/regulator/consumer.h>
19 #include <media/v4l2-async.h>
20 #include <media/v4l2-ctrls.h>
21 #include <media/v4l2-device.h>
22 #include <media/v4l2-fwnode.h>
23 #include <media/v4l2-subdev.h>
24 
25 #define MIPID02_CLK_LANE_WR_REG1			0x01
26 #define MIPID02_CLK_LANE_REG1				0x02
27 #define MIPID02_CLK_LANE_REG3				0x04
28 #define MIPID02_DATA_LANE0_REG1				0x05
29 #define MIPID02_DATA_LANE0_REG2				0x06
30 #define MIPID02_DATA_LANE1_REG1				0x09
31 #define MIPID02_DATA_LANE1_REG2				0x0a
32 #define MIPID02_MODE_REG1				0x14
33 #define MIPID02_MODE_REG2				0x15
34 #define MIPID02_DATA_ID_RREG				0x17
35 #define MIPID02_DATA_SELECTION_CTRL			0x19
36 #define MIPID02_PIX_WIDTH_CTRL				0x1e
37 #define MIPID02_PIX_WIDTH_CTRL_EMB			0x1f
38 
39 /* Bits definition for MIPID02_CLK_LANE_REG1 */
40 #define CLK_ENABLE					BIT(0)
41 /* Bits definition for MIPID02_CLK_LANE_REG3 */
42 #define CLK_MIPI_CSI					BIT(1)
43 /* Bits definition for MIPID02_DATA_LANE0_REG1 */
44 #define DATA_ENABLE					BIT(0)
45 /* Bits definition for MIPID02_DATA_LANEx_REG2 */
46 #define DATA_MIPI_CSI					BIT(0)
47 /* Bits definition for MIPID02_MODE_REG1 */
48 #define MODE_DATA_SWAP					BIT(2)
49 #define MODE_NO_BYPASS					BIT(6)
50 /* Bits definition for MIPID02_MODE_REG2 */
51 #define MODE_HSYNC_ACTIVE_HIGH				BIT(1)
52 #define MODE_VSYNC_ACTIVE_HIGH				BIT(2)
53 #define MODE_PCLK_SAMPLE_RISING				BIT(3)
54 /* Bits definition for MIPID02_DATA_SELECTION_CTRL */
55 #define SELECTION_MANUAL_DATA				BIT(2)
56 #define SELECTION_MANUAL_WIDTH				BIT(3)
57 
58 static const u32 mipid02_supported_fmt_codes[] = {
59 	MEDIA_BUS_FMT_SBGGR8_1X8, MEDIA_BUS_FMT_SGBRG8_1X8,
60 	MEDIA_BUS_FMT_SGRBG8_1X8, MEDIA_BUS_FMT_SRGGB8_1X8,
61 	MEDIA_BUS_FMT_SBGGR10_1X10, MEDIA_BUS_FMT_SGBRG10_1X10,
62 	MEDIA_BUS_FMT_SGRBG10_1X10, MEDIA_BUS_FMT_SRGGB10_1X10,
63 	MEDIA_BUS_FMT_SBGGR12_1X12, MEDIA_BUS_FMT_SGBRG12_1X12,
64 	MEDIA_BUS_FMT_SGRBG12_1X12, MEDIA_BUS_FMT_SRGGB12_1X12,
65 	MEDIA_BUS_FMT_YUYV8_1X16, MEDIA_BUS_FMT_YVYU8_1X16,
66 	MEDIA_BUS_FMT_UYVY8_1X16, MEDIA_BUS_FMT_VYUY8_1X16,
67 	MEDIA_BUS_FMT_RGB565_1X16, MEDIA_BUS_FMT_BGR888_1X24,
68 	MEDIA_BUS_FMT_RGB565_2X8_LE, MEDIA_BUS_FMT_RGB565_2X8_BE,
69 	MEDIA_BUS_FMT_YUYV8_2X8, MEDIA_BUS_FMT_YVYU8_2X8,
70 	MEDIA_BUS_FMT_UYVY8_2X8, MEDIA_BUS_FMT_VYUY8_2X8,
71 	MEDIA_BUS_FMT_JPEG_1X8
72 };
73 
74 /* regulator supplies */
75 static const char * const mipid02_supply_name[] = {
76 	"VDDE", /* 1.8V digital I/O supply */
77 	"VDDIN", /* 1V8 voltage regulator supply */
78 };
79 
80 #define MIPID02_NUM_SUPPLIES		ARRAY_SIZE(mipid02_supply_name)
81 
82 #define MIPID02_SINK_0			0
83 #define MIPID02_SINK_1			1
84 #define MIPID02_SOURCE			2
85 #define MIPID02_PAD_NB			3
86 
87 struct mipid02_dev {
88 	struct i2c_client *i2c_client;
89 	struct regulator_bulk_data supplies[MIPID02_NUM_SUPPLIES];
90 	struct v4l2_subdev sd;
91 	struct media_pad pad[MIPID02_PAD_NB];
92 	struct clk *xclk;
93 	struct gpio_desc *reset_gpio;
94 	/* endpoints info */
95 	struct v4l2_fwnode_endpoint rx;
96 	u64 link_frequency;
97 	struct v4l2_fwnode_endpoint tx;
98 	/* remote source */
99 	struct v4l2_async_notifier notifier;
100 	struct v4l2_subdev *s_subdev;
101 	/* registers */
102 	struct {
103 		u8 clk_lane_reg1;
104 		u8 data_lane0_reg1;
105 		u8 data_lane1_reg1;
106 		u8 mode_reg1;
107 		u8 mode_reg2;
108 		u8 data_selection_ctrl;
109 		u8 data_id_rreg;
110 		u8 pix_width_ctrl;
111 		u8 pix_width_ctrl_emb;
112 	} r;
113 	/* lock to protect all members below */
114 	struct mutex lock;
115 	bool streaming;
116 	struct v4l2_mbus_framefmt fmt;
117 };
118 
119 static int bpp_from_code(__u32 code)
120 {
121 	switch (code) {
122 	case MEDIA_BUS_FMT_SBGGR8_1X8:
123 	case MEDIA_BUS_FMT_SGBRG8_1X8:
124 	case MEDIA_BUS_FMT_SGRBG8_1X8:
125 	case MEDIA_BUS_FMT_SRGGB8_1X8:
126 		return 8;
127 	case MEDIA_BUS_FMT_SBGGR10_1X10:
128 	case MEDIA_BUS_FMT_SGBRG10_1X10:
129 	case MEDIA_BUS_FMT_SGRBG10_1X10:
130 	case MEDIA_BUS_FMT_SRGGB10_1X10:
131 		return 10;
132 	case MEDIA_BUS_FMT_SBGGR12_1X12:
133 	case MEDIA_BUS_FMT_SGBRG12_1X12:
134 	case MEDIA_BUS_FMT_SGRBG12_1X12:
135 	case MEDIA_BUS_FMT_SRGGB12_1X12:
136 		return 12;
137 	case MEDIA_BUS_FMT_YUYV8_1X16:
138 	case MEDIA_BUS_FMT_YVYU8_1X16:
139 	case MEDIA_BUS_FMT_UYVY8_1X16:
140 	case MEDIA_BUS_FMT_VYUY8_1X16:
141 	case MEDIA_BUS_FMT_RGB565_1X16:
142 	case MEDIA_BUS_FMT_YUYV8_2X8:
143 	case MEDIA_BUS_FMT_YVYU8_2X8:
144 	case MEDIA_BUS_FMT_UYVY8_2X8:
145 	case MEDIA_BUS_FMT_VYUY8_2X8:
146 	case MEDIA_BUS_FMT_RGB565_2X8_LE:
147 	case MEDIA_BUS_FMT_RGB565_2X8_BE:
148 		return 16;
149 	case MEDIA_BUS_FMT_BGR888_1X24:
150 		return 24;
151 	default:
152 		return 0;
153 	}
154 }
155 
156 static u8 data_type_from_code(__u32 code)
157 {
158 	switch (code) {
159 	case MEDIA_BUS_FMT_SBGGR8_1X8:
160 	case MEDIA_BUS_FMT_SGBRG8_1X8:
161 	case MEDIA_BUS_FMT_SGRBG8_1X8:
162 	case MEDIA_BUS_FMT_SRGGB8_1X8:
163 		return 0x2a;
164 	case MEDIA_BUS_FMT_SBGGR10_1X10:
165 	case MEDIA_BUS_FMT_SGBRG10_1X10:
166 	case MEDIA_BUS_FMT_SGRBG10_1X10:
167 	case MEDIA_BUS_FMT_SRGGB10_1X10:
168 		return 0x2b;
169 	case MEDIA_BUS_FMT_SBGGR12_1X12:
170 	case MEDIA_BUS_FMT_SGBRG12_1X12:
171 	case MEDIA_BUS_FMT_SGRBG12_1X12:
172 	case MEDIA_BUS_FMT_SRGGB12_1X12:
173 		return 0x2c;
174 	case MEDIA_BUS_FMT_YUYV8_1X16:
175 	case MEDIA_BUS_FMT_YVYU8_1X16:
176 	case MEDIA_BUS_FMT_UYVY8_1X16:
177 	case MEDIA_BUS_FMT_VYUY8_1X16:
178 	case MEDIA_BUS_FMT_YUYV8_2X8:
179 	case MEDIA_BUS_FMT_YVYU8_2X8:
180 	case MEDIA_BUS_FMT_UYVY8_2X8:
181 	case MEDIA_BUS_FMT_VYUY8_2X8:
182 		return 0x1e;
183 	case MEDIA_BUS_FMT_BGR888_1X24:
184 		return 0x24;
185 	case MEDIA_BUS_FMT_RGB565_1X16:
186 	case MEDIA_BUS_FMT_RGB565_2X8_LE:
187 	case MEDIA_BUS_FMT_RGB565_2X8_BE:
188 		return 0x22;
189 	default:
190 		return 0;
191 	}
192 }
193 
194 static void init_format(struct v4l2_mbus_framefmt *fmt)
195 {
196 	fmt->code = MEDIA_BUS_FMT_SBGGR8_1X8;
197 	fmt->field = V4L2_FIELD_NONE;
198 	fmt->colorspace = V4L2_COLORSPACE_SRGB;
199 	fmt->ycbcr_enc = V4L2_MAP_YCBCR_ENC_DEFAULT(V4L2_COLORSPACE_SRGB);
200 	fmt->quantization = V4L2_QUANTIZATION_FULL_RANGE;
201 	fmt->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(V4L2_COLORSPACE_SRGB);
202 	fmt->width = 640;
203 	fmt->height = 480;
204 }
205 
206 static __u32 get_fmt_code(__u32 code)
207 {
208 	unsigned int i;
209 
210 	for (i = 0; i < ARRAY_SIZE(mipid02_supported_fmt_codes); i++) {
211 		if (code == mipid02_supported_fmt_codes[i])
212 			return code;
213 	}
214 
215 	return mipid02_supported_fmt_codes[0];
216 }
217 
218 static __u32 serial_to_parallel_code(__u32 serial)
219 {
220 	if (serial == MEDIA_BUS_FMT_RGB565_1X16)
221 		return MEDIA_BUS_FMT_RGB565_2X8_LE;
222 	if (serial == MEDIA_BUS_FMT_YUYV8_1X16)
223 		return MEDIA_BUS_FMT_YUYV8_2X8;
224 	if (serial == MEDIA_BUS_FMT_YVYU8_1X16)
225 		return MEDIA_BUS_FMT_YVYU8_2X8;
226 	if (serial == MEDIA_BUS_FMT_UYVY8_1X16)
227 		return MEDIA_BUS_FMT_UYVY8_2X8;
228 	if (serial == MEDIA_BUS_FMT_VYUY8_1X16)
229 		return MEDIA_BUS_FMT_VYUY8_2X8;
230 	if (serial == MEDIA_BUS_FMT_BGR888_1X24)
231 		return MEDIA_BUS_FMT_BGR888_3X8;
232 
233 	return serial;
234 }
235 
236 static inline struct mipid02_dev *to_mipid02_dev(struct v4l2_subdev *sd)
237 {
238 	return container_of(sd, struct mipid02_dev, sd);
239 }
240 
241 static int mipid02_read_reg(struct mipid02_dev *bridge, u16 reg, u8 *val)
242 {
243 	struct i2c_client *client = bridge->i2c_client;
244 	struct i2c_msg msg[2];
245 	u8 buf[2];
246 	int ret;
247 
248 	buf[0] = reg >> 8;
249 	buf[1] = reg & 0xff;
250 
251 	msg[0].addr = client->addr;
252 	msg[0].flags = client->flags;
253 	msg[0].buf = buf;
254 	msg[0].len = sizeof(buf);
255 
256 	msg[1].addr = client->addr;
257 	msg[1].flags = client->flags | I2C_M_RD;
258 	msg[1].buf = val;
259 	msg[1].len = 1;
260 
261 	ret = i2c_transfer(client->adapter, msg, 2);
262 	if (ret < 0) {
263 		dev_dbg(&client->dev, "%s: %x i2c_transfer, reg: %x => %d\n",
264 			    __func__, client->addr, reg, ret);
265 		return ret;
266 	}
267 
268 	return 0;
269 }
270 
271 static int mipid02_write_reg(struct mipid02_dev *bridge, u16 reg, u8 val)
272 {
273 	struct i2c_client *client = bridge->i2c_client;
274 	struct i2c_msg msg;
275 	u8 buf[3];
276 	int ret;
277 
278 	buf[0] = reg >> 8;
279 	buf[1] = reg & 0xff;
280 	buf[2] = val;
281 
282 	msg.addr = client->addr;
283 	msg.flags = client->flags;
284 	msg.buf = buf;
285 	msg.len = sizeof(buf);
286 
287 	ret = i2c_transfer(client->adapter, &msg, 1);
288 	if (ret < 0) {
289 		dev_dbg(&client->dev, "%s: i2c_transfer, reg: %x => %d\n",
290 			    __func__, reg, ret);
291 		return ret;
292 	}
293 
294 	return 0;
295 }
296 
297 static int mipid02_get_regulators(struct mipid02_dev *bridge)
298 {
299 	unsigned int i;
300 
301 	for (i = 0; i < MIPID02_NUM_SUPPLIES; i++)
302 		bridge->supplies[i].supply = mipid02_supply_name[i];
303 
304 	return devm_regulator_bulk_get(&bridge->i2c_client->dev,
305 				       MIPID02_NUM_SUPPLIES,
306 				       bridge->supplies);
307 }
308 
309 static void mipid02_apply_reset(struct mipid02_dev *bridge)
310 {
311 	gpiod_set_value_cansleep(bridge->reset_gpio, 0);
312 	usleep_range(5000, 10000);
313 	gpiod_set_value_cansleep(bridge->reset_gpio, 1);
314 	usleep_range(5000, 10000);
315 	gpiod_set_value_cansleep(bridge->reset_gpio, 0);
316 	usleep_range(5000, 10000);
317 }
318 
319 static int mipid02_set_power_on(struct mipid02_dev *bridge)
320 {
321 	struct i2c_client *client = bridge->i2c_client;
322 	int ret;
323 
324 	ret = clk_prepare_enable(bridge->xclk);
325 	if (ret) {
326 		dev_err(&client->dev, "%s: failed to enable clock\n", __func__);
327 		return ret;
328 	}
329 
330 	ret = regulator_bulk_enable(MIPID02_NUM_SUPPLIES,
331 				    bridge->supplies);
332 	if (ret) {
333 		dev_err(&client->dev, "%s: failed to enable regulators\n",
334 			    __func__);
335 		goto xclk_off;
336 	}
337 
338 	if (bridge->reset_gpio) {
339 		dev_dbg(&client->dev, "apply reset");
340 		mipid02_apply_reset(bridge);
341 	} else {
342 		dev_dbg(&client->dev, "don't apply reset");
343 		usleep_range(5000, 10000);
344 	}
345 
346 	return 0;
347 
348 xclk_off:
349 	clk_disable_unprepare(bridge->xclk);
350 	return ret;
351 }
352 
353 static void mipid02_set_power_off(struct mipid02_dev *bridge)
354 {
355 	regulator_bulk_disable(MIPID02_NUM_SUPPLIES, bridge->supplies);
356 	clk_disable_unprepare(bridge->xclk);
357 }
358 
359 static int mipid02_detect(struct mipid02_dev *bridge)
360 {
361 	u8 reg;
362 
363 	/*
364 	 * There is no version registers. Just try to read register
365 	 * MIPID02_CLK_LANE_WR_REG1.
366 	 */
367 	return mipid02_read_reg(bridge, MIPID02_CLK_LANE_WR_REG1, &reg);
368 }
369 
370 static u32 mipid02_get_link_freq_from_cid_link_freq(struct mipid02_dev *bridge,
371 						    struct v4l2_subdev *subdev)
372 {
373 	struct v4l2_querymenu qm = {.id = V4L2_CID_LINK_FREQ, };
374 	struct v4l2_ctrl *ctrl;
375 	int ret;
376 
377 	ctrl = v4l2_ctrl_find(subdev->ctrl_handler, V4L2_CID_LINK_FREQ);
378 	if (!ctrl)
379 		return 0;
380 	qm.index = v4l2_ctrl_g_ctrl(ctrl);
381 
382 	ret = v4l2_querymenu(subdev->ctrl_handler, &qm);
383 	if (ret)
384 		return 0;
385 
386 	return qm.value;
387 }
388 
389 static u32 mipid02_get_link_freq_from_cid_pixel_rate(struct mipid02_dev *bridge,
390 						     struct v4l2_subdev *subdev)
391 {
392 	struct v4l2_fwnode_endpoint *ep = &bridge->rx;
393 	struct v4l2_ctrl *ctrl;
394 	u32 pixel_clock;
395 	u32 bpp = bpp_from_code(bridge->fmt.code);
396 
397 	ctrl = v4l2_ctrl_find(subdev->ctrl_handler, V4L2_CID_PIXEL_RATE);
398 	if (!ctrl)
399 		return 0;
400 	pixel_clock = v4l2_ctrl_g_ctrl_int64(ctrl);
401 
402 	return pixel_clock * bpp / (2 * ep->bus.mipi_csi2.num_data_lanes);
403 }
404 
405 /*
406  * We need to know link frequency to setup clk_lane_reg1 timings. Link frequency
407  * will be computed using connected device V4L2_CID_PIXEL_RATE, bit per pixel
408  * and number of lanes.
409  */
410 static int mipid02_configure_from_rx_speed(struct mipid02_dev *bridge)
411 {
412 	struct i2c_client *client = bridge->i2c_client;
413 	struct v4l2_subdev *subdev = bridge->s_subdev;
414 	u32 link_freq;
415 
416 	link_freq = mipid02_get_link_freq_from_cid_link_freq(bridge, subdev);
417 	if (!link_freq) {
418 		link_freq = mipid02_get_link_freq_from_cid_pixel_rate(bridge,
419 								      subdev);
420 		if (!link_freq) {
421 			dev_err(&client->dev, "Failed to get link frequency");
422 			return -EINVAL;
423 		}
424 	}
425 
426 	dev_dbg(&client->dev, "detect link_freq = %d Hz", link_freq);
427 	bridge->r.clk_lane_reg1 |= (2000000000 / link_freq) << 2;
428 
429 	return 0;
430 }
431 
432 static int mipid02_configure_clk_lane(struct mipid02_dev *bridge)
433 {
434 	struct i2c_client *client = bridge->i2c_client;
435 	struct v4l2_fwnode_endpoint *ep = &bridge->rx;
436 	bool *polarities = ep->bus.mipi_csi2.lane_polarities;
437 
438 	/* midid02 doesn't support clock lane remapping */
439 	if (ep->bus.mipi_csi2.clock_lane != 0) {
440 		dev_err(&client->dev, "clk lane must be map to lane 0\n");
441 		return -EINVAL;
442 	}
443 	bridge->r.clk_lane_reg1 |= (polarities[0] << 1) | CLK_ENABLE;
444 
445 	return 0;
446 }
447 
448 static int mipid02_configure_data0_lane(struct mipid02_dev *bridge, int nb,
449 					bool are_lanes_swap, bool *polarities)
450 {
451 	bool are_pin_swap = are_lanes_swap ? polarities[2] : polarities[1];
452 
453 	if (nb == 1 && are_lanes_swap)
454 		return 0;
455 
456 	/*
457 	 * data lane 0 as pin swap polarity reversed compared to clock and
458 	 * data lane 1
459 	 */
460 	if (!are_pin_swap)
461 		bridge->r.data_lane0_reg1 = 1 << 1;
462 	bridge->r.data_lane0_reg1 |= DATA_ENABLE;
463 
464 	return 0;
465 }
466 
467 static int mipid02_configure_data1_lane(struct mipid02_dev *bridge, int nb,
468 					bool are_lanes_swap, bool *polarities)
469 {
470 	bool are_pin_swap = are_lanes_swap ? polarities[1] : polarities[2];
471 
472 	if (nb == 1 && !are_lanes_swap)
473 		return 0;
474 
475 	if (are_pin_swap)
476 		bridge->r.data_lane1_reg1 = 1 << 1;
477 	bridge->r.data_lane1_reg1 |= DATA_ENABLE;
478 
479 	return 0;
480 }
481 
482 static int mipid02_configure_from_rx(struct mipid02_dev *bridge)
483 {
484 	struct v4l2_fwnode_endpoint *ep = &bridge->rx;
485 	bool are_lanes_swap = ep->bus.mipi_csi2.data_lanes[0] == 2;
486 	bool *polarities = ep->bus.mipi_csi2.lane_polarities;
487 	int nb = ep->bus.mipi_csi2.num_data_lanes;
488 	int ret;
489 
490 	ret = mipid02_configure_clk_lane(bridge);
491 	if (ret)
492 		return ret;
493 
494 	ret = mipid02_configure_data0_lane(bridge, nb, are_lanes_swap,
495 					   polarities);
496 	if (ret)
497 		return ret;
498 
499 	ret = mipid02_configure_data1_lane(bridge, nb, are_lanes_swap,
500 					   polarities);
501 	if (ret)
502 		return ret;
503 
504 	bridge->r.mode_reg1 |= are_lanes_swap ? MODE_DATA_SWAP : 0;
505 	bridge->r.mode_reg1 |= (nb - 1) << 1;
506 
507 	return mipid02_configure_from_rx_speed(bridge);
508 }
509 
510 static int mipid02_configure_from_tx(struct mipid02_dev *bridge)
511 {
512 	struct v4l2_fwnode_endpoint *ep = &bridge->tx;
513 
514 	bridge->r.data_selection_ctrl = SELECTION_MANUAL_WIDTH;
515 	bridge->r.pix_width_ctrl = ep->bus.parallel.bus_width;
516 	bridge->r.pix_width_ctrl_emb = ep->bus.parallel.bus_width;
517 	if (ep->bus.parallel.flags & V4L2_MBUS_HSYNC_ACTIVE_HIGH)
518 		bridge->r.mode_reg2 |= MODE_HSYNC_ACTIVE_HIGH;
519 	if (ep->bus.parallel.flags & V4L2_MBUS_VSYNC_ACTIVE_HIGH)
520 		bridge->r.mode_reg2 |= MODE_VSYNC_ACTIVE_HIGH;
521 	if (ep->bus.parallel.flags & V4L2_MBUS_PCLK_SAMPLE_RISING)
522 		bridge->r.mode_reg2 |= MODE_PCLK_SAMPLE_RISING;
523 
524 	return 0;
525 }
526 
527 static int mipid02_configure_from_code(struct mipid02_dev *bridge)
528 {
529 	u8 data_type;
530 
531 	bridge->r.data_id_rreg = 0;
532 
533 	if (bridge->fmt.code != MEDIA_BUS_FMT_JPEG_1X8) {
534 		bridge->r.data_selection_ctrl |= SELECTION_MANUAL_DATA;
535 
536 		data_type = data_type_from_code(bridge->fmt.code);
537 		if (!data_type)
538 			return -EINVAL;
539 		bridge->r.data_id_rreg = data_type;
540 	}
541 
542 	return 0;
543 }
544 
545 static int mipid02_stream_disable(struct mipid02_dev *bridge)
546 {
547 	struct i2c_client *client = bridge->i2c_client;
548 	int ret = -EINVAL;
549 
550 	if (!bridge->s_subdev)
551 		goto error;
552 
553 	ret = v4l2_subdev_call(bridge->s_subdev, video, s_stream, 0);
554 	if (ret)
555 		goto error;
556 
557 	/* Disable all lanes */
558 	ret = mipid02_write_reg(bridge, MIPID02_CLK_LANE_REG1, 0);
559 	if (ret)
560 		goto error;
561 	ret = mipid02_write_reg(bridge, MIPID02_DATA_LANE0_REG1, 0);
562 	if (ret)
563 		goto error;
564 	ret = mipid02_write_reg(bridge, MIPID02_DATA_LANE1_REG1, 0);
565 	if (ret)
566 		goto error;
567 error:
568 	if (ret)
569 		dev_err(&client->dev, "failed to stream off %d", ret);
570 
571 	return ret;
572 }
573 
574 static int mipid02_stream_enable(struct mipid02_dev *bridge)
575 {
576 	struct i2c_client *client = bridge->i2c_client;
577 	int ret = -EINVAL;
578 
579 	if (!bridge->s_subdev)
580 		goto error;
581 
582 	memset(&bridge->r, 0, sizeof(bridge->r));
583 	/* build registers content */
584 	ret = mipid02_configure_from_rx(bridge);
585 	if (ret)
586 		goto error;
587 	ret = mipid02_configure_from_tx(bridge);
588 	if (ret)
589 		goto error;
590 	ret = mipid02_configure_from_code(bridge);
591 	if (ret)
592 		goto error;
593 
594 	/* write mipi registers */
595 	ret = mipid02_write_reg(bridge, MIPID02_CLK_LANE_REG1,
596 		bridge->r.clk_lane_reg1);
597 	if (ret)
598 		goto error;
599 	ret = mipid02_write_reg(bridge, MIPID02_CLK_LANE_REG3, CLK_MIPI_CSI);
600 	if (ret)
601 		goto error;
602 	ret = mipid02_write_reg(bridge, MIPID02_DATA_LANE0_REG1,
603 		bridge->r.data_lane0_reg1);
604 	if (ret)
605 		goto error;
606 	ret = mipid02_write_reg(bridge, MIPID02_DATA_LANE0_REG2,
607 		DATA_MIPI_CSI);
608 	if (ret)
609 		goto error;
610 	ret = mipid02_write_reg(bridge, MIPID02_DATA_LANE1_REG1,
611 		bridge->r.data_lane1_reg1);
612 	if (ret)
613 		goto error;
614 	ret = mipid02_write_reg(bridge, MIPID02_DATA_LANE1_REG2,
615 		DATA_MIPI_CSI);
616 	if (ret)
617 		goto error;
618 	ret = mipid02_write_reg(bridge, MIPID02_MODE_REG1,
619 		MODE_NO_BYPASS | bridge->r.mode_reg1);
620 	if (ret)
621 		goto error;
622 	ret = mipid02_write_reg(bridge, MIPID02_MODE_REG2,
623 		bridge->r.mode_reg2);
624 	if (ret)
625 		goto error;
626 	ret = mipid02_write_reg(bridge, MIPID02_DATA_ID_RREG,
627 		bridge->r.data_id_rreg);
628 	if (ret)
629 		goto error;
630 	ret = mipid02_write_reg(bridge, MIPID02_DATA_SELECTION_CTRL,
631 		bridge->r.data_selection_ctrl);
632 	if (ret)
633 		goto error;
634 	ret = mipid02_write_reg(bridge, MIPID02_PIX_WIDTH_CTRL,
635 		bridge->r.pix_width_ctrl);
636 	if (ret)
637 		goto error;
638 	ret = mipid02_write_reg(bridge, MIPID02_PIX_WIDTH_CTRL_EMB,
639 		bridge->r.pix_width_ctrl_emb);
640 	if (ret)
641 		goto error;
642 
643 	ret = v4l2_subdev_call(bridge->s_subdev, video, s_stream, 1);
644 	if (ret)
645 		goto error;
646 
647 	return 0;
648 
649 error:
650 	dev_err(&client->dev, "failed to stream on %d", ret);
651 	mipid02_stream_disable(bridge);
652 
653 	return ret;
654 }
655 
656 static int mipid02_s_stream(struct v4l2_subdev *sd, int enable)
657 {
658 	struct mipid02_dev *bridge = to_mipid02_dev(sd);
659 	struct i2c_client *client = bridge->i2c_client;
660 	int ret = 0;
661 
662 	dev_dbg(&client->dev, "%s : requested %d / current = %d", __func__,
663 		    enable, bridge->streaming);
664 	mutex_lock(&bridge->lock);
665 
666 	if (bridge->streaming == enable)
667 		goto out;
668 
669 	ret = enable ? mipid02_stream_enable(bridge) :
670 		       mipid02_stream_disable(bridge);
671 	if (!ret)
672 		bridge->streaming = enable;
673 
674 out:
675 	dev_dbg(&client->dev, "%s current now = %d / %d", __func__,
676 		    bridge->streaming, ret);
677 	mutex_unlock(&bridge->lock);
678 
679 	return ret;
680 }
681 
682 static int mipid02_enum_mbus_code(struct v4l2_subdev *sd,
683 				 struct v4l2_subdev_state *sd_state,
684 				 struct v4l2_subdev_mbus_code_enum *code)
685 {
686 	struct mipid02_dev *bridge = to_mipid02_dev(sd);
687 	int ret = 0;
688 
689 	switch (code->pad) {
690 	case MIPID02_SINK_0:
691 		if (code->index >= ARRAY_SIZE(mipid02_supported_fmt_codes))
692 			ret = -EINVAL;
693 		else
694 			code->code = mipid02_supported_fmt_codes[code->index];
695 		break;
696 	case MIPID02_SOURCE:
697 		if (code->index == 0)
698 			code->code = serial_to_parallel_code(bridge->fmt.code);
699 		else
700 			ret = -EINVAL;
701 		break;
702 	default:
703 		ret = -EINVAL;
704 	}
705 
706 	return ret;
707 }
708 
709 static int mipid02_get_fmt(struct v4l2_subdev *sd,
710 			   struct v4l2_subdev_state *sd_state,
711 			   struct v4l2_subdev_format *format)
712 {
713 	struct v4l2_mbus_framefmt *mbus_fmt = &format->format;
714 	struct mipid02_dev *bridge = to_mipid02_dev(sd);
715 	struct i2c_client *client = bridge->i2c_client;
716 	struct v4l2_mbus_framefmt *fmt;
717 
718 	dev_dbg(&client->dev, "%s probe %d", __func__, format->pad);
719 
720 	if (format->pad >= MIPID02_PAD_NB)
721 		return -EINVAL;
722 	/* second CSI-2 pad not yet supported */
723 	if (format->pad == MIPID02_SINK_1)
724 		return -EINVAL;
725 
726 	if (format->which == V4L2_SUBDEV_FORMAT_TRY)
727 		fmt = v4l2_subdev_get_try_format(&bridge->sd, sd_state,
728 						 format->pad);
729 	else
730 		fmt = &bridge->fmt;
731 
732 	mutex_lock(&bridge->lock);
733 
734 	*mbus_fmt = *fmt;
735 	/* code may need to be converted for source */
736 	if (format->pad == MIPID02_SOURCE)
737 		mbus_fmt->code = serial_to_parallel_code(mbus_fmt->code);
738 
739 	mutex_unlock(&bridge->lock);
740 
741 	return 0;
742 }
743 
744 static void mipid02_set_fmt_source(struct v4l2_subdev *sd,
745 				   struct v4l2_subdev_state *sd_state,
746 				   struct v4l2_subdev_format *format)
747 {
748 	struct mipid02_dev *bridge = to_mipid02_dev(sd);
749 
750 	/* source pad mirror sink pad */
751 	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
752 		format->format = bridge->fmt;
753 	else
754 		format->format = *v4l2_subdev_get_try_format(sd, sd_state,
755 							     MIPID02_SINK_0);
756 
757 	/* but code may need to be converted */
758 	format->format.code = serial_to_parallel_code(format->format.code);
759 
760 	/* only apply format for V4L2_SUBDEV_FORMAT_TRY case */
761 	if (format->which != V4L2_SUBDEV_FORMAT_TRY)
762 		return;
763 
764 	*v4l2_subdev_get_try_format(sd, sd_state, MIPID02_SOURCE) =
765 		format->format;
766 }
767 
768 static void mipid02_set_fmt_sink(struct v4l2_subdev *sd,
769 				 struct v4l2_subdev_state *sd_state,
770 				 struct v4l2_subdev_format *format)
771 {
772 	struct mipid02_dev *bridge = to_mipid02_dev(sd);
773 	struct v4l2_mbus_framefmt *fmt;
774 
775 	format->format.code = get_fmt_code(format->format.code);
776 
777 	if (format->which == V4L2_SUBDEV_FORMAT_TRY)
778 		fmt = v4l2_subdev_get_try_format(sd, sd_state, format->pad);
779 	else
780 		fmt = &bridge->fmt;
781 
782 	*fmt = format->format;
783 
784 	/* Propagate the format change to the source pad */
785 	mipid02_set_fmt_source(sd, sd_state, format);
786 }
787 
788 static int mipid02_set_fmt(struct v4l2_subdev *sd,
789 			   struct v4l2_subdev_state *sd_state,
790 			   struct v4l2_subdev_format *format)
791 {
792 	struct mipid02_dev *bridge = to_mipid02_dev(sd);
793 	struct i2c_client *client = bridge->i2c_client;
794 	int ret = 0;
795 
796 	dev_dbg(&client->dev, "%s for %d", __func__, format->pad);
797 
798 	if (format->pad >= MIPID02_PAD_NB)
799 		return -EINVAL;
800 	/* second CSI-2 pad not yet supported */
801 	if (format->pad == MIPID02_SINK_1)
802 		return -EINVAL;
803 
804 	mutex_lock(&bridge->lock);
805 
806 	if (bridge->streaming) {
807 		ret = -EBUSY;
808 		goto error;
809 	}
810 
811 	if (format->pad == MIPID02_SOURCE)
812 		mipid02_set_fmt_source(sd, sd_state, format);
813 	else
814 		mipid02_set_fmt_sink(sd, sd_state, format);
815 
816 error:
817 	mutex_unlock(&bridge->lock);
818 
819 	return ret;
820 }
821 
822 static const struct v4l2_subdev_video_ops mipid02_video_ops = {
823 	.s_stream = mipid02_s_stream,
824 };
825 
826 static const struct v4l2_subdev_pad_ops mipid02_pad_ops = {
827 	.enum_mbus_code = mipid02_enum_mbus_code,
828 	.get_fmt = mipid02_get_fmt,
829 	.set_fmt = mipid02_set_fmt,
830 };
831 
832 static const struct v4l2_subdev_ops mipid02_subdev_ops = {
833 	.video = &mipid02_video_ops,
834 	.pad = &mipid02_pad_ops,
835 };
836 
837 static const struct media_entity_operations mipid02_subdev_entity_ops = {
838 	.link_validate = v4l2_subdev_link_validate,
839 };
840 
841 static int mipid02_async_bound(struct v4l2_async_notifier *notifier,
842 			       struct v4l2_subdev *s_subdev,
843 			       struct v4l2_async_connection *asd)
844 {
845 	struct mipid02_dev *bridge = to_mipid02_dev(notifier->sd);
846 	struct i2c_client *client = bridge->i2c_client;
847 	int source_pad;
848 	int ret;
849 
850 	dev_dbg(&client->dev, "sensor_async_bound call %p", s_subdev);
851 
852 	source_pad = media_entity_get_fwnode_pad(&s_subdev->entity,
853 						 s_subdev->fwnode,
854 						 MEDIA_PAD_FL_SOURCE);
855 	if (source_pad < 0) {
856 		dev_err(&client->dev, "Couldn't find output pad for subdev %s\n",
857 			s_subdev->name);
858 		return source_pad;
859 	}
860 
861 	ret = media_create_pad_link(&s_subdev->entity, source_pad,
862 				    &bridge->sd.entity, 0,
863 				    MEDIA_LNK_FL_ENABLED |
864 				    MEDIA_LNK_FL_IMMUTABLE);
865 	if (ret) {
866 		dev_err(&client->dev, "Couldn't create media link %d", ret);
867 		return ret;
868 	}
869 
870 	bridge->s_subdev = s_subdev;
871 
872 	return 0;
873 }
874 
875 static void mipid02_async_unbind(struct v4l2_async_notifier *notifier,
876 				 struct v4l2_subdev *s_subdev,
877 				 struct v4l2_async_connection *asd)
878 {
879 	struct mipid02_dev *bridge = to_mipid02_dev(notifier->sd);
880 
881 	bridge->s_subdev = NULL;
882 }
883 
884 static const struct v4l2_async_notifier_operations mipid02_notifier_ops = {
885 	.bound		= mipid02_async_bound,
886 	.unbind		= mipid02_async_unbind,
887 };
888 
889 static int mipid02_parse_rx_ep(struct mipid02_dev *bridge)
890 {
891 	struct v4l2_fwnode_endpoint ep = { .bus_type = V4L2_MBUS_CSI2_DPHY };
892 	struct i2c_client *client = bridge->i2c_client;
893 	struct v4l2_async_connection *asd;
894 	struct device_node *ep_node;
895 	int ret;
896 
897 	/* parse rx (endpoint 0) */
898 	ep_node = of_graph_get_endpoint_by_regs(bridge->i2c_client->dev.of_node,
899 						0, 0);
900 	if (!ep_node) {
901 		dev_err(&client->dev, "unable to find port0 ep");
902 		ret = -EINVAL;
903 		goto error;
904 	}
905 
906 	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep_node), &ep);
907 	if (ret) {
908 		dev_err(&client->dev, "Could not parse v4l2 endpoint %d\n",
909 			ret);
910 		goto error_of_node_put;
911 	}
912 
913 	/* do some sanity checks */
914 	if (ep.bus.mipi_csi2.num_data_lanes > 2) {
915 		dev_err(&client->dev, "max supported data lanes is 2 / got %d",
916 			ep.bus.mipi_csi2.num_data_lanes);
917 		ret = -EINVAL;
918 		goto error_of_node_put;
919 	}
920 
921 	/* register it for later use */
922 	bridge->rx = ep;
923 
924 	/* register async notifier so we get noticed when sensor is connected */
925 	v4l2_async_subdev_nf_init(&bridge->notifier, &bridge->sd);
926 	asd = v4l2_async_nf_add_fwnode_remote(&bridge->notifier,
927 					      of_fwnode_handle(ep_node),
928 					      struct v4l2_async_connection);
929 	of_node_put(ep_node);
930 
931 	if (IS_ERR(asd)) {
932 		dev_err(&client->dev, "fail to register asd to notifier %ld",
933 			PTR_ERR(asd));
934 		return PTR_ERR(asd);
935 	}
936 	bridge->notifier.ops = &mipid02_notifier_ops;
937 
938 	ret = v4l2_async_nf_register(&bridge->notifier);
939 	if (ret)
940 		v4l2_async_nf_cleanup(&bridge->notifier);
941 
942 	return ret;
943 
944 error_of_node_put:
945 	of_node_put(ep_node);
946 error:
947 
948 	return ret;
949 }
950 
951 static int mipid02_parse_tx_ep(struct mipid02_dev *bridge)
952 {
953 	struct v4l2_fwnode_endpoint ep = { .bus_type = V4L2_MBUS_PARALLEL };
954 	struct i2c_client *client = bridge->i2c_client;
955 	struct device_node *ep_node;
956 	int ret;
957 
958 	/* parse tx (endpoint 2) */
959 	ep_node = of_graph_get_endpoint_by_regs(bridge->i2c_client->dev.of_node,
960 						2, 0);
961 	if (!ep_node) {
962 		dev_err(&client->dev, "unable to find port1 ep");
963 		ret = -EINVAL;
964 		goto error;
965 	}
966 
967 	ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep_node), &ep);
968 	if (ret) {
969 		dev_err(&client->dev, "Could not parse v4l2 endpoint\n");
970 		goto error_of_node_put;
971 	}
972 
973 	of_node_put(ep_node);
974 	bridge->tx = ep;
975 
976 	return 0;
977 
978 error_of_node_put:
979 	of_node_put(ep_node);
980 error:
981 
982 	return -EINVAL;
983 }
984 
985 static int mipid02_probe(struct i2c_client *client)
986 {
987 	struct device *dev = &client->dev;
988 	struct mipid02_dev *bridge;
989 	u32 clk_freq;
990 	int ret;
991 
992 	bridge = devm_kzalloc(dev, sizeof(*bridge), GFP_KERNEL);
993 	if (!bridge)
994 		return -ENOMEM;
995 
996 	init_format(&bridge->fmt);
997 
998 	bridge->i2c_client = client;
999 	v4l2_i2c_subdev_init(&bridge->sd, client, &mipid02_subdev_ops);
1000 
1001 	/* got and check clock */
1002 	bridge->xclk = devm_clk_get(dev, "xclk");
1003 	if (IS_ERR(bridge->xclk)) {
1004 		dev_err(dev, "failed to get xclk\n");
1005 		return PTR_ERR(bridge->xclk);
1006 	}
1007 
1008 	clk_freq = clk_get_rate(bridge->xclk);
1009 	if (clk_freq < 6000000 || clk_freq > 27000000) {
1010 		dev_err(dev, "xclk freq must be in 6-27 Mhz range. got %d Hz\n",
1011 			clk_freq);
1012 		return -EINVAL;
1013 	}
1014 
1015 	bridge->reset_gpio = devm_gpiod_get_optional(dev, "reset",
1016 						     GPIOD_OUT_HIGH);
1017 
1018 	if (IS_ERR(bridge->reset_gpio)) {
1019 		dev_err(dev, "failed to get reset GPIO\n");
1020 		return PTR_ERR(bridge->reset_gpio);
1021 	}
1022 
1023 	ret = mipid02_get_regulators(bridge);
1024 	if (ret) {
1025 		dev_err(dev, "failed to get regulators %d", ret);
1026 		return ret;
1027 	}
1028 
1029 	mutex_init(&bridge->lock);
1030 	bridge->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
1031 	bridge->sd.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
1032 	bridge->sd.entity.ops = &mipid02_subdev_entity_ops;
1033 	bridge->pad[0].flags = MEDIA_PAD_FL_SINK;
1034 	bridge->pad[1].flags = MEDIA_PAD_FL_SINK;
1035 	bridge->pad[2].flags = MEDIA_PAD_FL_SOURCE;
1036 	ret = media_entity_pads_init(&bridge->sd.entity, MIPID02_PAD_NB,
1037 				     bridge->pad);
1038 	if (ret) {
1039 		dev_err(&client->dev, "pads init failed %d", ret);
1040 		goto mutex_cleanup;
1041 	}
1042 
1043 	/* enable clock, power and reset device if available */
1044 	ret = mipid02_set_power_on(bridge);
1045 	if (ret)
1046 		goto entity_cleanup;
1047 
1048 	ret = mipid02_detect(bridge);
1049 	if (ret) {
1050 		dev_err(&client->dev, "failed to detect mipid02 %d", ret);
1051 		goto power_off;
1052 	}
1053 
1054 	ret = mipid02_parse_tx_ep(bridge);
1055 	if (ret) {
1056 		dev_err(&client->dev, "failed to parse tx %d", ret);
1057 		goto power_off;
1058 	}
1059 
1060 	ret = mipid02_parse_rx_ep(bridge);
1061 	if (ret) {
1062 		dev_err(&client->dev, "failed to parse rx %d", ret);
1063 		goto power_off;
1064 	}
1065 
1066 	ret = v4l2_async_register_subdev(&bridge->sd);
1067 	if (ret < 0) {
1068 		dev_err(&client->dev, "v4l2_async_register_subdev failed %d",
1069 			    ret);
1070 		goto unregister_notifier;
1071 	}
1072 
1073 	dev_info(&client->dev, "mipid02 device probe successfully");
1074 
1075 	return 0;
1076 
1077 unregister_notifier:
1078 	v4l2_async_nf_unregister(&bridge->notifier);
1079 	v4l2_async_nf_cleanup(&bridge->notifier);
1080 power_off:
1081 	mipid02_set_power_off(bridge);
1082 entity_cleanup:
1083 	media_entity_cleanup(&bridge->sd.entity);
1084 mutex_cleanup:
1085 	mutex_destroy(&bridge->lock);
1086 
1087 	return ret;
1088 }
1089 
1090 static void mipid02_remove(struct i2c_client *client)
1091 {
1092 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
1093 	struct mipid02_dev *bridge = to_mipid02_dev(sd);
1094 
1095 	v4l2_async_nf_unregister(&bridge->notifier);
1096 	v4l2_async_nf_cleanup(&bridge->notifier);
1097 	v4l2_async_unregister_subdev(&bridge->sd);
1098 	mipid02_set_power_off(bridge);
1099 	media_entity_cleanup(&bridge->sd.entity);
1100 	mutex_destroy(&bridge->lock);
1101 }
1102 
1103 static const struct of_device_id mipid02_dt_ids[] = {
1104 	{ .compatible = "st,st-mipid02" },
1105 	{ /* sentinel */ }
1106 };
1107 MODULE_DEVICE_TABLE(of, mipid02_dt_ids);
1108 
1109 static struct i2c_driver mipid02_i2c_driver = {
1110 	.driver = {
1111 		.name  = "st-mipid02",
1112 		.of_match_table = mipid02_dt_ids,
1113 	},
1114 	.probe = mipid02_probe,
1115 	.remove = mipid02_remove,
1116 };
1117 
1118 module_i2c_driver(mipid02_i2c_driver);
1119 
1120 MODULE_AUTHOR("Mickael Guene <mickael.guene@st.com>");
1121 MODULE_DESCRIPTION("STMicroelectronics MIPID02 CSI-2 bridge driver");
1122 MODULE_LICENSE("GPL v2");
1123