1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for Xilinx MIPI CSI-2 Rx Subsystem
4  *
5  * Copyright (C) 2016 - 2020 Xilinx, Inc.
6  *
7  * Contacts: Vishal Sagar <vishal.sagar@xilinx.com>
8  *
9  */
10 #include <linux/clk.h>
11 #include <linux/delay.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/interrupt.h>
14 #include <linux/module.h>
15 #include <linux/mutex.h>
16 #include <linux/of.h>
17 #include <linux/of_irq.h>
18 #include <linux/platform_device.h>
19 #include <linux/v4l2-subdev.h>
20 #include <media/media-entity.h>
21 #include <media/mipi-csi2.h>
22 #include <media/v4l2-common.h>
23 #include <media/v4l2-ctrls.h>
24 #include <media/v4l2-fwnode.h>
25 #include <media/v4l2-subdev.h>
26 #include "xilinx-vip.h"
27 
28 /* Register register map */
29 #define XCSI_CCR_OFFSET		0x00
30 #define XCSI_CCR_SOFTRESET	BIT(1)
31 #define XCSI_CCR_ENABLE		BIT(0)
32 
33 #define XCSI_PCR_OFFSET		0x04
34 #define XCSI_PCR_MAXLANES_MASK	GENMASK(4, 3)
35 #define XCSI_PCR_ACTLANES_MASK	GENMASK(1, 0)
36 
37 #define XCSI_CSR_OFFSET		0x10
38 #define XCSI_CSR_PKTCNT		GENMASK(31, 16)
39 #define XCSI_CSR_SPFIFOFULL	BIT(3)
40 #define XCSI_CSR_SPFIFONE	BIT(2)
41 #define XCSI_CSR_SLBF		BIT(1)
42 #define XCSI_CSR_RIPCD		BIT(0)
43 
44 #define XCSI_GIER_OFFSET	0x20
45 #define XCSI_GIER_GIE		BIT(0)
46 
47 #define XCSI_ISR_OFFSET		0x24
48 #define XCSI_IER_OFFSET		0x28
49 
50 #define XCSI_ISR_FR		BIT(31)
51 #define XCSI_ISR_VCXFE		BIT(30)
52 #define XCSI_ISR_WCC		BIT(22)
53 #define XCSI_ISR_ILC		BIT(21)
54 #define XCSI_ISR_SPFIFOF	BIT(20)
55 #define XCSI_ISR_SPFIFONE	BIT(19)
56 #define XCSI_ISR_SLBF		BIT(18)
57 #define XCSI_ISR_STOP		BIT(17)
58 #define XCSI_ISR_SOTERR		BIT(13)
59 #define XCSI_ISR_SOTSYNCERR	BIT(12)
60 #define XCSI_ISR_ECC2BERR	BIT(11)
61 #define XCSI_ISR_ECC1BERR	BIT(10)
62 #define XCSI_ISR_CRCERR		BIT(9)
63 #define XCSI_ISR_DATAIDERR	BIT(8)
64 #define XCSI_ISR_VC3FSYNCERR	BIT(7)
65 #define XCSI_ISR_VC3FLVLERR	BIT(6)
66 #define XCSI_ISR_VC2FSYNCERR	BIT(5)
67 #define XCSI_ISR_VC2FLVLERR	BIT(4)
68 #define XCSI_ISR_VC1FSYNCERR	BIT(3)
69 #define XCSI_ISR_VC1FLVLERR	BIT(2)
70 #define XCSI_ISR_VC0FSYNCERR	BIT(1)
71 #define XCSI_ISR_VC0FLVLERR	BIT(0)
72 
73 #define XCSI_ISR_ALLINTR_MASK	(0xc07e3fff)
74 
75 /*
76  * Removed VCXFE mask as it doesn't exist in IER
77  * Removed STOP state irq as this will keep driver in irq handler only
78  */
79 #define XCSI_IER_INTR_MASK	(XCSI_ISR_ALLINTR_MASK &\
80 				 ~(XCSI_ISR_STOP | XCSI_ISR_VCXFE))
81 
82 #define XCSI_SPKTR_OFFSET	0x30
83 #define XCSI_SPKTR_DATA		GENMASK(23, 8)
84 #define XCSI_SPKTR_VC		GENMASK(7, 6)
85 #define XCSI_SPKTR_DT		GENMASK(5, 0)
86 #define XCSI_SPKT_FIFO_DEPTH	31
87 
88 #define XCSI_VCXR_OFFSET	0x34
89 #define XCSI_VCXR_VCERR		GENMASK(23, 0)
90 #define XCSI_VCXR_FSYNCERR	BIT(1)
91 #define XCSI_VCXR_FLVLERR	BIT(0)
92 
93 #define XCSI_CLKINFR_OFFSET	0x3C
94 #define XCSI_CLKINFR_STOP	BIT(1)
95 
96 #define XCSI_DLXINFR_OFFSET	0x40
97 #define XCSI_DLXINFR_STOP	BIT(5)
98 #define XCSI_DLXINFR_SOTERR	BIT(1)
99 #define XCSI_DLXINFR_SOTSYNCERR	BIT(0)
100 #define XCSI_MAXDL_COUNT	0x4
101 
102 #define XCSI_VCXINF1R_OFFSET		0x60
103 #define XCSI_VCXINF1R_LINECOUNT		GENMASK(31, 16)
104 #define XCSI_VCXINF1R_LINECOUNT_SHIFT	16
105 #define XCSI_VCXINF1R_BYTECOUNT		GENMASK(15, 0)
106 
107 #define XCSI_VCXINF2R_OFFSET	0x64
108 #define XCSI_VCXINF2R_DT	GENMASK(5, 0)
109 #define XCSI_MAXVCX_COUNT	16
110 
111 /*
112  * Sink pad connected to sensor source pad.
113  * Source pad connected to next module like demosaic.
114  */
115 #define XCSI_MEDIA_PADS		2
116 #define XCSI_DEFAULT_WIDTH	1920
117 #define XCSI_DEFAULT_HEIGHT	1080
118 
119 #define XCSI_VCX_START		4
120 #define XCSI_MAX_VC		4
121 #define XCSI_MAX_VCX		16
122 
123 #define XCSI_NEXTREG_OFFSET	4
124 
125 /* There are 2 events frame sync and frame level error per VC */
126 #define XCSI_VCX_NUM_EVENTS	((XCSI_MAX_VCX - XCSI_MAX_VC) * 2)
127 
128 /**
129  * struct xcsi2rxss_event - Event log structure
130  * @mask: Event mask
131  * @name: Name of the event
132  */
133 struct xcsi2rxss_event {
134 	u32 mask;
135 	const char *name;
136 };
137 
138 static const struct xcsi2rxss_event xcsi2rxss_events[] = {
139 	{ XCSI_ISR_FR, "Frame Received" },
140 	{ XCSI_ISR_VCXFE, "VCX Frame Errors" },
141 	{ XCSI_ISR_WCC, "Word Count Errors" },
142 	{ XCSI_ISR_ILC, "Invalid Lane Count Error" },
143 	{ XCSI_ISR_SPFIFOF, "Short Packet FIFO OverFlow Error" },
144 	{ XCSI_ISR_SPFIFONE, "Short Packet FIFO Not Empty" },
145 	{ XCSI_ISR_SLBF, "Streamline Buffer Full Error" },
146 	{ XCSI_ISR_STOP, "Lane Stop State" },
147 	{ XCSI_ISR_SOTERR, "SOT Error" },
148 	{ XCSI_ISR_SOTSYNCERR, "SOT Sync Error" },
149 	{ XCSI_ISR_ECC2BERR, "2 Bit ECC Unrecoverable Error" },
150 	{ XCSI_ISR_ECC1BERR, "1 Bit ECC Recoverable Error" },
151 	{ XCSI_ISR_CRCERR, "CRC Error" },
152 	{ XCSI_ISR_DATAIDERR, "Data Id Error" },
153 	{ XCSI_ISR_VC3FSYNCERR, "Virtual Channel 3 Frame Sync Error" },
154 	{ XCSI_ISR_VC3FLVLERR, "Virtual Channel 3 Frame Level Error" },
155 	{ XCSI_ISR_VC2FSYNCERR, "Virtual Channel 2 Frame Sync Error" },
156 	{ XCSI_ISR_VC2FLVLERR, "Virtual Channel 2 Frame Level Error" },
157 	{ XCSI_ISR_VC1FSYNCERR, "Virtual Channel 1 Frame Sync Error" },
158 	{ XCSI_ISR_VC1FLVLERR, "Virtual Channel 1 Frame Level Error" },
159 	{ XCSI_ISR_VC0FSYNCERR, "Virtual Channel 0 Frame Sync Error" },
160 	{ XCSI_ISR_VC0FLVLERR, "Virtual Channel 0 Frame Level Error" }
161 };
162 
163 #define XCSI_NUM_EVENTS		ARRAY_SIZE(xcsi2rxss_events)
164 
165 /*
166  * This table provides a mapping between CSI-2 Data type
167  * and media bus formats
168  */
169 static const u32 xcsi2dt_mbus_lut[][2] = {
170 	{ MIPI_CSI2_DT_YUV422_8B, MEDIA_BUS_FMT_UYVY8_1X16 },
171 	{ MIPI_CSI2_DT_YUV422_10B, MEDIA_BUS_FMT_UYVY10_1X20 },
172 	{ MIPI_CSI2_DT_RGB444, 0 },
173 	{ MIPI_CSI2_DT_RGB555, 0 },
174 	{ MIPI_CSI2_DT_RGB565, 0 },
175 	{ MIPI_CSI2_DT_RGB666, 0 },
176 	{ MIPI_CSI2_DT_RGB888, MEDIA_BUS_FMT_RBG888_1X24 },
177 	{ MIPI_CSI2_DT_RAW6, 0 },
178 	{ MIPI_CSI2_DT_RAW7, 0 },
179 	{ MIPI_CSI2_DT_RAW8, MEDIA_BUS_FMT_SRGGB8_1X8 },
180 	{ MIPI_CSI2_DT_RAW8, MEDIA_BUS_FMT_SBGGR8_1X8 },
181 	{ MIPI_CSI2_DT_RAW8, MEDIA_BUS_FMT_SGBRG8_1X8 },
182 	{ MIPI_CSI2_DT_RAW8, MEDIA_BUS_FMT_SGRBG8_1X8 },
183 	{ MIPI_CSI2_DT_RAW10, MEDIA_BUS_FMT_SRGGB10_1X10 },
184 	{ MIPI_CSI2_DT_RAW10, MEDIA_BUS_FMT_SBGGR10_1X10 },
185 	{ MIPI_CSI2_DT_RAW10, MEDIA_BUS_FMT_SGBRG10_1X10 },
186 	{ MIPI_CSI2_DT_RAW10, MEDIA_BUS_FMT_SGRBG10_1X10 },
187 	{ MIPI_CSI2_DT_RAW12, MEDIA_BUS_FMT_SRGGB12_1X12 },
188 	{ MIPI_CSI2_DT_RAW12, MEDIA_BUS_FMT_SBGGR12_1X12 },
189 	{ MIPI_CSI2_DT_RAW12, MEDIA_BUS_FMT_SGBRG12_1X12 },
190 	{ MIPI_CSI2_DT_RAW12, MEDIA_BUS_FMT_SGRBG12_1X12 },
191 	{ MIPI_CSI2_DT_RAW12, MEDIA_BUS_FMT_Y12_1X12 },
192 	{ MIPI_CSI2_DT_RAW16, MEDIA_BUS_FMT_SRGGB16_1X16 },
193 	{ MIPI_CSI2_DT_RAW16, MEDIA_BUS_FMT_SBGGR16_1X16 },
194 	{ MIPI_CSI2_DT_RAW16, MEDIA_BUS_FMT_SGBRG16_1X16 },
195 	{ MIPI_CSI2_DT_RAW16, MEDIA_BUS_FMT_SGRBG16_1X16 },
196 	{ MIPI_CSI2_DT_RAW20, 0 },
197 };
198 
199 /**
200  * struct xcsi2rxss_state - CSI-2 Rx Subsystem device structure
201  * @subdev: The v4l2 subdev structure
202  * @format: Active V4L2 formats on each pad
203  * @default_format: Default V4L2 format
204  * @events: counter for events
205  * @vcx_events: counter for vcx_events
206  * @dev: Platform structure
207  * @rsubdev: Remote subdev connected to sink pad
208  * @rst_gpio: reset to video_aresetn
209  * @clks: array of clocks
210  * @iomem: Base address of subsystem
211  * @max_num_lanes: Maximum number of lanes present
212  * @datatype: Data type filter
213  * @lock: mutex for accessing this structure
214  * @pads: media pads
215  * @streaming: Flag for storing streaming state
216  * @enable_active_lanes: If number of active lanes can be modified
217  * @en_vcx: If more than 4 VC are enabled
218  *
219  * This structure contains the device driver related parameters
220  */
221 struct xcsi2rxss_state {
222 	struct v4l2_subdev subdev;
223 	struct v4l2_mbus_framefmt format;
224 	struct v4l2_mbus_framefmt default_format;
225 	u32 events[XCSI_NUM_EVENTS];
226 	u32 vcx_events[XCSI_VCX_NUM_EVENTS];
227 	struct device *dev;
228 	struct v4l2_subdev *rsubdev;
229 	struct gpio_desc *rst_gpio;
230 	struct clk_bulk_data *clks;
231 	void __iomem *iomem;
232 	u32 max_num_lanes;
233 	u32 datatype;
234 	/* used to protect access to this struct */
235 	struct mutex lock;
236 	struct media_pad pads[XCSI_MEDIA_PADS];
237 	bool streaming;
238 	bool enable_active_lanes;
239 	bool en_vcx;
240 };
241 
242 static const struct clk_bulk_data xcsi2rxss_clks[] = {
243 	{ .id = "lite_aclk" },
244 	{ .id = "video_aclk" },
245 };
246 
247 static inline struct xcsi2rxss_state *
248 to_xcsi2rxssstate(struct v4l2_subdev *subdev)
249 {
250 	return container_of(subdev, struct xcsi2rxss_state, subdev);
251 }
252 
253 /*
254  * Register related operations
255  */
256 static inline u32 xcsi2rxss_read(struct xcsi2rxss_state *xcsi2rxss, u32 addr)
257 {
258 	return ioread32(xcsi2rxss->iomem + addr);
259 }
260 
261 static inline void xcsi2rxss_write(struct xcsi2rxss_state *xcsi2rxss, u32 addr,
262 				   u32 value)
263 {
264 	iowrite32(value, xcsi2rxss->iomem + addr);
265 }
266 
267 static inline void xcsi2rxss_clr(struct xcsi2rxss_state *xcsi2rxss, u32 addr,
268 				 u32 clr)
269 {
270 	xcsi2rxss_write(xcsi2rxss, addr,
271 			xcsi2rxss_read(xcsi2rxss, addr) & ~clr);
272 }
273 
274 static inline void xcsi2rxss_set(struct xcsi2rxss_state *xcsi2rxss, u32 addr,
275 				 u32 set)
276 {
277 	xcsi2rxss_write(xcsi2rxss, addr, xcsi2rxss_read(xcsi2rxss, addr) | set);
278 }
279 
280 /*
281  * This function returns the nth mbus for a data type.
282  * In case of error, mbus code returned is 0.
283  */
284 static u32 xcsi2rxss_get_nth_mbus(u32 dt, u32 n)
285 {
286 	unsigned int i;
287 
288 	for (i = 0; i < ARRAY_SIZE(xcsi2dt_mbus_lut); i++) {
289 		if (xcsi2dt_mbus_lut[i][0] == dt) {
290 			if (n-- == 0)
291 				return xcsi2dt_mbus_lut[i][1];
292 		}
293 	}
294 
295 	return 0;
296 }
297 
298 /* This returns the data type for a media bus format else 0 */
299 static u32 xcsi2rxss_get_dt(u32 mbus)
300 {
301 	unsigned int i;
302 
303 	for (i = 0; i < ARRAY_SIZE(xcsi2dt_mbus_lut); i++) {
304 		if (xcsi2dt_mbus_lut[i][1] == mbus)
305 			return xcsi2dt_mbus_lut[i][0];
306 	}
307 
308 	return 0;
309 }
310 
311 /**
312  * xcsi2rxss_soft_reset - Does a soft reset of the MIPI CSI-2 Rx Subsystem
313  * @state: Xilinx CSI-2 Rx Subsystem structure pointer
314  *
315  * Core takes less than 100 video clock cycles to reset.
316  * So a larger timeout value is chosen for margin.
317  *
318  * Return: 0 - on success OR -ETIME if reset times out
319  */
320 static int xcsi2rxss_soft_reset(struct xcsi2rxss_state *state)
321 {
322 	u32 timeout = 1000; /* us */
323 
324 	xcsi2rxss_set(state, XCSI_CCR_OFFSET, XCSI_CCR_SOFTRESET);
325 
326 	while (xcsi2rxss_read(state, XCSI_CSR_OFFSET) & XCSI_CSR_RIPCD) {
327 		if (timeout == 0) {
328 			dev_err(state->dev, "soft reset timed out!\n");
329 			return -ETIME;
330 		}
331 
332 		timeout--;
333 		udelay(1);
334 	}
335 
336 	xcsi2rxss_clr(state, XCSI_CCR_OFFSET, XCSI_CCR_SOFTRESET);
337 	return 0;
338 }
339 
340 static void xcsi2rxss_hard_reset(struct xcsi2rxss_state *state)
341 {
342 	if (!state->rst_gpio)
343 		return;
344 
345 	/* minimum of 40 dphy_clk_200M cycles */
346 	gpiod_set_value_cansleep(state->rst_gpio, 1);
347 	usleep_range(1, 2);
348 	gpiod_set_value_cansleep(state->rst_gpio, 0);
349 }
350 
351 static void xcsi2rxss_reset_event_counters(struct xcsi2rxss_state *state)
352 {
353 	unsigned int i;
354 
355 	for (i = 0; i < XCSI_NUM_EVENTS; i++)
356 		state->events[i] = 0;
357 
358 	for (i = 0; i < XCSI_VCX_NUM_EVENTS; i++)
359 		state->vcx_events[i] = 0;
360 }
361 
362 /* Print event counters */
363 static void xcsi2rxss_log_counters(struct xcsi2rxss_state *state)
364 {
365 	struct device *dev = state->dev;
366 	unsigned int i;
367 
368 	for (i = 0; i < XCSI_NUM_EVENTS; i++) {
369 		if (state->events[i] > 0) {
370 			dev_info(dev, "%s events: %d\n",
371 				 xcsi2rxss_events[i].name,
372 				 state->events[i]);
373 		}
374 	}
375 
376 	if (state->en_vcx) {
377 		for (i = 0; i < XCSI_VCX_NUM_EVENTS; i++) {
378 			if (state->vcx_events[i] > 0) {
379 				dev_info(dev,
380 					 "VC %d Frame %s err vcx events: %d\n",
381 					 (i / 2) + XCSI_VCX_START,
382 					 i & 1 ? "Sync" : "Level",
383 					 state->vcx_events[i]);
384 			}
385 		}
386 	}
387 }
388 
389 static int xcsi2rxss_log_status(struct v4l2_subdev *sd)
390 {
391 	struct xcsi2rxss_state *xcsi2rxss = to_xcsi2rxssstate(sd);
392 	struct device *dev = xcsi2rxss->dev;
393 	u32 reg, data;
394 	unsigned int i, max_vc;
395 
396 	mutex_lock(&xcsi2rxss->lock);
397 
398 	xcsi2rxss_log_counters(xcsi2rxss);
399 
400 	dev_info(dev, "***** Core Status *****\n");
401 	data = xcsi2rxss_read(xcsi2rxss, XCSI_CSR_OFFSET);
402 	dev_info(dev, "Short Packet FIFO Full = %s\n",
403 		 data & XCSI_CSR_SPFIFOFULL ? "true" : "false");
404 	dev_info(dev, "Short Packet FIFO Not Empty = %s\n",
405 		 data & XCSI_CSR_SPFIFONE ? "true" : "false");
406 	dev_info(dev, "Stream line buffer full = %s\n",
407 		 data & XCSI_CSR_SLBF ? "true" : "false");
408 	dev_info(dev, "Soft reset/Core disable in progress = %s\n",
409 		 data & XCSI_CSR_RIPCD ? "true" : "false");
410 
411 	/* Clk & Lane Info  */
412 	dev_info(dev, "******** Clock Lane Info *********\n");
413 	data = xcsi2rxss_read(xcsi2rxss, XCSI_CLKINFR_OFFSET);
414 	dev_info(dev, "Clock Lane in Stop State = %s\n",
415 		 data & XCSI_CLKINFR_STOP ? "true" : "false");
416 
417 	dev_info(dev, "******** Data Lane Info *********\n");
418 	dev_info(dev, "Lane\tSoT Error\tSoT Sync Error\tStop State\n");
419 	reg = XCSI_DLXINFR_OFFSET;
420 	for (i = 0; i < XCSI_MAXDL_COUNT; i++) {
421 		data = xcsi2rxss_read(xcsi2rxss, reg);
422 
423 		dev_info(dev, "%d\t%s\t\t%s\t\t%s\n", i,
424 			 data & XCSI_DLXINFR_SOTERR ? "true" : "false",
425 			 data & XCSI_DLXINFR_SOTSYNCERR ? "true" : "false",
426 			 data & XCSI_DLXINFR_STOP ? "true" : "false");
427 
428 		reg += XCSI_NEXTREG_OFFSET;
429 	}
430 
431 	/* Virtual Channel Image Information */
432 	dev_info(dev, "********** Virtual Channel Info ************\n");
433 	dev_info(dev, "VC\tLine Count\tByte Count\tData Type\n");
434 	if (xcsi2rxss->en_vcx)
435 		max_vc = XCSI_MAX_VCX;
436 	else
437 		max_vc = XCSI_MAX_VC;
438 
439 	reg = XCSI_VCXINF1R_OFFSET;
440 	for (i = 0; i < max_vc; i++) {
441 		u32 line_count, byte_count, data_type;
442 
443 		/* Get line and byte count from VCXINFR1 Register */
444 		data = xcsi2rxss_read(xcsi2rxss, reg);
445 		byte_count = data & XCSI_VCXINF1R_BYTECOUNT;
446 		line_count = data & XCSI_VCXINF1R_LINECOUNT;
447 		line_count >>= XCSI_VCXINF1R_LINECOUNT_SHIFT;
448 
449 		/* Get data type from VCXINFR2 Register */
450 		reg += XCSI_NEXTREG_OFFSET;
451 		data = xcsi2rxss_read(xcsi2rxss, reg);
452 		data_type = data & XCSI_VCXINF2R_DT;
453 
454 		dev_info(dev, "%d\t%d\t\t%d\t\t0x%x\n", i, line_count,
455 			 byte_count, data_type);
456 
457 		/* Move to next pair of VC Info registers */
458 		reg += XCSI_NEXTREG_OFFSET;
459 	}
460 
461 	mutex_unlock(&xcsi2rxss->lock);
462 
463 	return 0;
464 }
465 
466 static struct v4l2_subdev *xcsi2rxss_get_remote_subdev(struct media_pad *local)
467 {
468 	struct media_pad *remote;
469 
470 	remote = media_pad_remote_pad_first(local);
471 	if (!remote || !is_media_entity_v4l2_subdev(remote->entity))
472 		return NULL;
473 
474 	return media_entity_to_v4l2_subdev(remote->entity);
475 }
476 
477 static int xcsi2rxss_start_stream(struct xcsi2rxss_state *state)
478 {
479 	int ret = 0;
480 
481 	/* enable core */
482 	xcsi2rxss_set(state, XCSI_CCR_OFFSET, XCSI_CCR_ENABLE);
483 
484 	ret = xcsi2rxss_soft_reset(state);
485 	if (ret) {
486 		state->streaming = false;
487 		return ret;
488 	}
489 
490 	/* enable interrupts */
491 	xcsi2rxss_clr(state, XCSI_GIER_OFFSET, XCSI_GIER_GIE);
492 	xcsi2rxss_write(state, XCSI_IER_OFFSET, XCSI_IER_INTR_MASK);
493 	xcsi2rxss_set(state, XCSI_GIER_OFFSET, XCSI_GIER_GIE);
494 
495 	state->streaming = true;
496 
497 	state->rsubdev =
498 		xcsi2rxss_get_remote_subdev(&state->pads[XVIP_PAD_SINK]);
499 
500 	ret = v4l2_subdev_call(state->rsubdev, video, s_stream, 1);
501 	if (ret) {
502 		/* disable interrupts */
503 		xcsi2rxss_clr(state, XCSI_IER_OFFSET, XCSI_IER_INTR_MASK);
504 		xcsi2rxss_clr(state, XCSI_GIER_OFFSET, XCSI_GIER_GIE);
505 
506 		/* disable core */
507 		xcsi2rxss_clr(state, XCSI_CCR_OFFSET, XCSI_CCR_ENABLE);
508 		state->streaming = false;
509 	}
510 
511 	return ret;
512 }
513 
514 static void xcsi2rxss_stop_stream(struct xcsi2rxss_state *state)
515 {
516 	v4l2_subdev_call(state->rsubdev, video, s_stream, 0);
517 
518 	/* disable interrupts */
519 	xcsi2rxss_clr(state, XCSI_IER_OFFSET, XCSI_IER_INTR_MASK);
520 	xcsi2rxss_clr(state, XCSI_GIER_OFFSET, XCSI_GIER_GIE);
521 
522 	/* disable core */
523 	xcsi2rxss_clr(state, XCSI_CCR_OFFSET, XCSI_CCR_ENABLE);
524 	state->streaming = false;
525 }
526 
527 /**
528  * xcsi2rxss_irq_handler - Interrupt handler for CSI-2
529  * @irq: IRQ number
530  * @data: Pointer to device state
531  *
532  * In the interrupt handler, a list of event counters are updated for
533  * corresponding interrupts. This is useful to get status / debug.
534  *
535  * Return: IRQ_HANDLED after handling interrupts
536  */
537 static irqreturn_t xcsi2rxss_irq_handler(int irq, void *data)
538 {
539 	struct xcsi2rxss_state *state = (struct xcsi2rxss_state *)data;
540 	struct device *dev = state->dev;
541 	u32 status;
542 
543 	status = xcsi2rxss_read(state, XCSI_ISR_OFFSET) & XCSI_ISR_ALLINTR_MASK;
544 	xcsi2rxss_write(state, XCSI_ISR_OFFSET, status);
545 
546 	/* Received a short packet */
547 	if (status & XCSI_ISR_SPFIFONE) {
548 		u32 count = 0;
549 
550 		/*
551 		 * Drain generic short packet FIFO by reading max 31
552 		 * (fifo depth) short packets from fifo or till fifo is empty.
553 		 */
554 		for (count = 0; count < XCSI_SPKT_FIFO_DEPTH; ++count) {
555 			u32 spfifostat, spkt;
556 
557 			spkt = xcsi2rxss_read(state, XCSI_SPKTR_OFFSET);
558 			dev_dbg(dev, "Short packet = 0x%08x\n", spkt);
559 			spfifostat = xcsi2rxss_read(state, XCSI_ISR_OFFSET);
560 			spfifostat &= XCSI_ISR_SPFIFONE;
561 			if (!spfifostat)
562 				break;
563 			xcsi2rxss_write(state, XCSI_ISR_OFFSET, spfifostat);
564 		}
565 	}
566 
567 	/* Short packet FIFO overflow */
568 	if (status & XCSI_ISR_SPFIFOF)
569 		dev_dbg_ratelimited(dev, "Short packet FIFO overflowed\n");
570 
571 	/*
572 	 * Stream line buffer full
573 	 * This means there is a backpressure from downstream IP
574 	 */
575 	if (status & XCSI_ISR_SLBF) {
576 		dev_alert_ratelimited(dev, "Stream Line Buffer Full!\n");
577 
578 		/* disable interrupts */
579 		xcsi2rxss_clr(state, XCSI_IER_OFFSET, XCSI_IER_INTR_MASK);
580 		xcsi2rxss_clr(state, XCSI_GIER_OFFSET, XCSI_GIER_GIE);
581 
582 		/* disable core */
583 		xcsi2rxss_clr(state, XCSI_CCR_OFFSET, XCSI_CCR_ENABLE);
584 
585 		/*
586 		 * The IP needs to be hard reset before it can be used now.
587 		 * This will be done in streamoff.
588 		 */
589 
590 		/*
591 		 * TODO: Notify the whole pipeline with v4l2_subdev_notify() to
592 		 * inform userspace.
593 		 */
594 	}
595 
596 	/* Increment event counters */
597 	if (status & XCSI_ISR_ALLINTR_MASK) {
598 		unsigned int i;
599 
600 		for (i = 0; i < XCSI_NUM_EVENTS; i++) {
601 			if (!(status & xcsi2rxss_events[i].mask))
602 				continue;
603 			state->events[i]++;
604 			dev_dbg_ratelimited(dev, "%s: %u\n",
605 					    xcsi2rxss_events[i].name,
606 					    state->events[i]);
607 		}
608 
609 		if (status & XCSI_ISR_VCXFE && state->en_vcx) {
610 			u32 vcxstatus;
611 
612 			vcxstatus = xcsi2rxss_read(state, XCSI_VCXR_OFFSET);
613 			vcxstatus &= XCSI_VCXR_VCERR;
614 			for (i = 0; i < XCSI_VCX_NUM_EVENTS; i++) {
615 				if (!(vcxstatus & BIT(i)))
616 					continue;
617 				state->vcx_events[i]++;
618 			}
619 			xcsi2rxss_write(state, XCSI_VCXR_OFFSET, vcxstatus);
620 		}
621 	}
622 
623 	return IRQ_HANDLED;
624 }
625 
626 static int xcsi2rxss_s_stream(struct v4l2_subdev *sd, int enable)
627 {
628 	struct xcsi2rxss_state *xcsi2rxss = to_xcsi2rxssstate(sd);
629 	int ret = 0;
630 
631 	mutex_lock(&xcsi2rxss->lock);
632 
633 	if (enable == xcsi2rxss->streaming)
634 		goto stream_done;
635 
636 	if (enable) {
637 		xcsi2rxss_reset_event_counters(xcsi2rxss);
638 		ret = xcsi2rxss_start_stream(xcsi2rxss);
639 	} else {
640 		xcsi2rxss_stop_stream(xcsi2rxss);
641 		xcsi2rxss_hard_reset(xcsi2rxss);
642 	}
643 
644 stream_done:
645 	mutex_unlock(&xcsi2rxss->lock);
646 	return ret;
647 }
648 
649 static struct v4l2_mbus_framefmt *
650 __xcsi2rxss_get_pad_format(struct xcsi2rxss_state *xcsi2rxss,
651 			   struct v4l2_subdev_state *sd_state,
652 			   unsigned int pad, u32 which)
653 {
654 	switch (which) {
655 	case V4L2_SUBDEV_FORMAT_TRY:
656 		return v4l2_subdev_state_get_format(sd_state, pad);
657 	case V4L2_SUBDEV_FORMAT_ACTIVE:
658 		return &xcsi2rxss->format;
659 	default:
660 		return NULL;
661 	}
662 }
663 
664 static int xcsi2rxss_init_state(struct v4l2_subdev *sd,
665 				struct v4l2_subdev_state *sd_state)
666 {
667 	struct xcsi2rxss_state *xcsi2rxss = to_xcsi2rxssstate(sd);
668 	struct v4l2_mbus_framefmt *format;
669 	unsigned int i;
670 
671 	mutex_lock(&xcsi2rxss->lock);
672 	for (i = 0; i < XCSI_MEDIA_PADS; i++) {
673 		format = v4l2_subdev_state_get_format(sd_state, i);
674 		*format = xcsi2rxss->default_format;
675 	}
676 	mutex_unlock(&xcsi2rxss->lock);
677 
678 	return 0;
679 }
680 
681 static int xcsi2rxss_get_format(struct v4l2_subdev *sd,
682 				struct v4l2_subdev_state *sd_state,
683 				struct v4l2_subdev_format *fmt)
684 {
685 	struct xcsi2rxss_state *xcsi2rxss = to_xcsi2rxssstate(sd);
686 
687 	mutex_lock(&xcsi2rxss->lock);
688 	fmt->format = *__xcsi2rxss_get_pad_format(xcsi2rxss, sd_state,
689 						  fmt->pad,
690 						  fmt->which);
691 	mutex_unlock(&xcsi2rxss->lock);
692 
693 	return 0;
694 }
695 
696 static int xcsi2rxss_set_format(struct v4l2_subdev *sd,
697 				struct v4l2_subdev_state *sd_state,
698 				struct v4l2_subdev_format *fmt)
699 {
700 	struct xcsi2rxss_state *xcsi2rxss = to_xcsi2rxssstate(sd);
701 	struct v4l2_mbus_framefmt *__format;
702 	u32 dt;
703 
704 	mutex_lock(&xcsi2rxss->lock);
705 
706 	/*
707 	 * Only the format->code parameter matters for CSI as the
708 	 * CSI format cannot be changed at runtime.
709 	 * Ensure that format to set is copied to over to CSI pad format
710 	 */
711 	__format = __xcsi2rxss_get_pad_format(xcsi2rxss, sd_state,
712 					      fmt->pad, fmt->which);
713 
714 	/* only sink pad format can be updated */
715 	if (fmt->pad == XVIP_PAD_SOURCE) {
716 		fmt->format = *__format;
717 		mutex_unlock(&xcsi2rxss->lock);
718 		return 0;
719 	}
720 
721 	/*
722 	 * RAW8 is supported in all datatypes. So if requested media bus format
723 	 * is of RAW8 type, then allow to be set. In case core is configured to
724 	 * other RAW, YUV422 8/10 or RGB888, set appropriate media bus format.
725 	 */
726 	dt = xcsi2rxss_get_dt(fmt->format.code);
727 	if (dt != xcsi2rxss->datatype && dt != MIPI_CSI2_DT_RAW8) {
728 		dev_dbg(xcsi2rxss->dev, "Unsupported media bus format");
729 		/* set the default format for the data type */
730 		fmt->format.code = xcsi2rxss_get_nth_mbus(xcsi2rxss->datatype,
731 							  0);
732 	}
733 
734 	*__format = fmt->format;
735 	mutex_unlock(&xcsi2rxss->lock);
736 
737 	return 0;
738 }
739 
740 static int xcsi2rxss_enum_mbus_code(struct v4l2_subdev *sd,
741 				    struct v4l2_subdev_state *sd_state,
742 				    struct v4l2_subdev_mbus_code_enum *code)
743 {
744 	struct xcsi2rxss_state *state = to_xcsi2rxssstate(sd);
745 	u32 dt, n;
746 	int ret = 0;
747 
748 	/* RAW8 dt packets are available in all DT configurations */
749 	if (code->index < 4) {
750 		n = code->index;
751 		dt = MIPI_CSI2_DT_RAW8;
752 	} else if (state->datatype != MIPI_CSI2_DT_RAW8) {
753 		n = code->index - 4;
754 		dt = state->datatype;
755 	} else {
756 		return -EINVAL;
757 	}
758 
759 	code->code = xcsi2rxss_get_nth_mbus(dt, n);
760 	if (!code->code)
761 		ret = -EINVAL;
762 
763 	return ret;
764 }
765 
766 /* -----------------------------------------------------------------------------
767  * Media Operations
768  */
769 
770 static const struct media_entity_operations xcsi2rxss_media_ops = {
771 	.link_validate = v4l2_subdev_link_validate
772 };
773 
774 static const struct v4l2_subdev_core_ops xcsi2rxss_core_ops = {
775 	.log_status = xcsi2rxss_log_status,
776 };
777 
778 static const struct v4l2_subdev_video_ops xcsi2rxss_video_ops = {
779 	.s_stream = xcsi2rxss_s_stream
780 };
781 
782 static const struct v4l2_subdev_pad_ops xcsi2rxss_pad_ops = {
783 	.get_fmt = xcsi2rxss_get_format,
784 	.set_fmt = xcsi2rxss_set_format,
785 	.enum_mbus_code = xcsi2rxss_enum_mbus_code,
786 	.link_validate = v4l2_subdev_link_validate_default,
787 };
788 
789 static const struct v4l2_subdev_ops xcsi2rxss_ops = {
790 	.core = &xcsi2rxss_core_ops,
791 	.video = &xcsi2rxss_video_ops,
792 	.pad = &xcsi2rxss_pad_ops
793 };
794 
795 static const struct v4l2_subdev_internal_ops xcsi2rxss_internal_ops = {
796 	.init_state = xcsi2rxss_init_state,
797 };
798 
799 static int xcsi2rxss_parse_of(struct xcsi2rxss_state *xcsi2rxss)
800 {
801 	struct device *dev = xcsi2rxss->dev;
802 	struct device_node *node = dev->of_node;
803 
804 	struct fwnode_handle *ep;
805 	struct v4l2_fwnode_endpoint vep = {
806 		.bus_type = V4L2_MBUS_CSI2_DPHY
807 	};
808 	bool en_csi_v20, vfb;
809 	int ret;
810 
811 	en_csi_v20 = of_property_read_bool(node, "xlnx,en-csi-v2-0");
812 	if (en_csi_v20)
813 		xcsi2rxss->en_vcx = of_property_read_bool(node, "xlnx,en-vcx");
814 
815 	xcsi2rxss->enable_active_lanes =
816 		of_property_read_bool(node, "xlnx,en-active-lanes");
817 
818 	ret = of_property_read_u32(node, "xlnx,csi-pxl-format",
819 				   &xcsi2rxss->datatype);
820 	if (ret < 0) {
821 		dev_err(dev, "missing xlnx,csi-pxl-format property\n");
822 		return ret;
823 	}
824 
825 	switch (xcsi2rxss->datatype) {
826 	case MIPI_CSI2_DT_YUV422_8B:
827 	case MIPI_CSI2_DT_RGB444:
828 	case MIPI_CSI2_DT_RGB555:
829 	case MIPI_CSI2_DT_RGB565:
830 	case MIPI_CSI2_DT_RGB666:
831 	case MIPI_CSI2_DT_RGB888:
832 	case MIPI_CSI2_DT_RAW6:
833 	case MIPI_CSI2_DT_RAW7:
834 	case MIPI_CSI2_DT_RAW8:
835 	case MIPI_CSI2_DT_RAW10:
836 	case MIPI_CSI2_DT_RAW12:
837 	case MIPI_CSI2_DT_RAW14:
838 		break;
839 	case MIPI_CSI2_DT_YUV422_10B:
840 	case MIPI_CSI2_DT_RAW16:
841 	case MIPI_CSI2_DT_RAW20:
842 		if (!en_csi_v20) {
843 			ret = -EINVAL;
844 			dev_dbg(dev, "enable csi v2 for this pixel format");
845 		}
846 		break;
847 	default:
848 		ret = -EINVAL;
849 	}
850 	if (ret < 0) {
851 		dev_err(dev, "invalid csi-pxl-format property!\n");
852 		return ret;
853 	}
854 
855 	vfb = of_property_read_bool(node, "xlnx,vfb");
856 	if (!vfb) {
857 		dev_err(dev, "operation without VFB is not supported\n");
858 		return -EINVAL;
859 	}
860 
861 	ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev),
862 					     XVIP_PAD_SINK, 0,
863 					     FWNODE_GRAPH_ENDPOINT_NEXT);
864 	if (!ep) {
865 		dev_err(dev, "no sink port found");
866 		return -EINVAL;
867 	}
868 
869 	ret = v4l2_fwnode_endpoint_parse(ep, &vep);
870 	fwnode_handle_put(ep);
871 	if (ret) {
872 		dev_err(dev, "error parsing sink port");
873 		return ret;
874 	}
875 
876 	dev_dbg(dev, "mipi number lanes = %d\n",
877 		vep.bus.mipi_csi2.num_data_lanes);
878 
879 	xcsi2rxss->max_num_lanes = vep.bus.mipi_csi2.num_data_lanes;
880 
881 	ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev),
882 					     XVIP_PAD_SOURCE, 0,
883 					     FWNODE_GRAPH_ENDPOINT_NEXT);
884 	if (!ep) {
885 		dev_err(dev, "no source port found");
886 		return -EINVAL;
887 	}
888 
889 	fwnode_handle_put(ep);
890 
891 	dev_dbg(dev, "vcx %s, %u data lanes (%s), data type 0x%02x\n",
892 		xcsi2rxss->en_vcx ? "enabled" : "disabled",
893 		xcsi2rxss->max_num_lanes,
894 		xcsi2rxss->enable_active_lanes ? "dynamic" : "static",
895 		xcsi2rxss->datatype);
896 
897 	return 0;
898 }
899 
900 static int xcsi2rxss_probe(struct platform_device *pdev)
901 {
902 	struct v4l2_subdev *subdev;
903 	struct xcsi2rxss_state *xcsi2rxss;
904 	int num_clks = ARRAY_SIZE(xcsi2rxss_clks);
905 	struct device *dev = &pdev->dev;
906 	int irq, ret;
907 
908 	xcsi2rxss = devm_kzalloc(dev, sizeof(*xcsi2rxss), GFP_KERNEL);
909 	if (!xcsi2rxss)
910 		return -ENOMEM;
911 
912 	xcsi2rxss->dev = dev;
913 
914 	xcsi2rxss->clks = devm_kmemdup(dev, xcsi2rxss_clks,
915 				       sizeof(xcsi2rxss_clks), GFP_KERNEL);
916 	if (!xcsi2rxss->clks)
917 		return -ENOMEM;
918 
919 	/* Reset GPIO */
920 	xcsi2rxss->rst_gpio = devm_gpiod_get_optional(dev, "video-reset",
921 						      GPIOD_OUT_HIGH);
922 	if (IS_ERR(xcsi2rxss->rst_gpio))
923 		return dev_err_probe(dev, PTR_ERR(xcsi2rxss->rst_gpio),
924 				     "Video Reset GPIO not setup in DT\n");
925 
926 	ret = xcsi2rxss_parse_of(xcsi2rxss);
927 	if (ret < 0)
928 		return ret;
929 
930 	xcsi2rxss->iomem = devm_platform_ioremap_resource(pdev, 0);
931 	if (IS_ERR(xcsi2rxss->iomem))
932 		return PTR_ERR(xcsi2rxss->iomem);
933 
934 	irq = platform_get_irq(pdev, 0);
935 	if (irq < 0)
936 		return irq;
937 
938 	ret = devm_request_threaded_irq(dev, irq, NULL,
939 					xcsi2rxss_irq_handler, IRQF_ONESHOT,
940 					dev_name(dev), xcsi2rxss);
941 	if (ret) {
942 		dev_err(dev, "Err = %d Interrupt handler reg failed!\n", ret);
943 		return ret;
944 	}
945 
946 	ret = clk_bulk_get(dev, num_clks, xcsi2rxss->clks);
947 	if (ret)
948 		return ret;
949 
950 	/* TODO: Enable/disable clocks at stream on/off time. */
951 	ret = clk_bulk_prepare_enable(num_clks, xcsi2rxss->clks);
952 	if (ret)
953 		goto err_clk_put;
954 
955 	mutex_init(&xcsi2rxss->lock);
956 
957 	xcsi2rxss_hard_reset(xcsi2rxss);
958 	xcsi2rxss_soft_reset(xcsi2rxss);
959 
960 	/* Initialize V4L2 subdevice and media entity */
961 	xcsi2rxss->pads[XVIP_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
962 	xcsi2rxss->pads[XVIP_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
963 
964 	/* Initialize the default format */
965 	xcsi2rxss->default_format.code =
966 		xcsi2rxss_get_nth_mbus(xcsi2rxss->datatype, 0);
967 	xcsi2rxss->default_format.field = V4L2_FIELD_NONE;
968 	xcsi2rxss->default_format.colorspace = V4L2_COLORSPACE_SRGB;
969 	xcsi2rxss->default_format.width = XCSI_DEFAULT_WIDTH;
970 	xcsi2rxss->default_format.height = XCSI_DEFAULT_HEIGHT;
971 	xcsi2rxss->format = xcsi2rxss->default_format;
972 
973 	/* Initialize V4L2 subdevice and media entity */
974 	subdev = &xcsi2rxss->subdev;
975 	v4l2_subdev_init(subdev, &xcsi2rxss_ops);
976 	subdev->internal_ops = &xcsi2rxss_internal_ops;
977 	subdev->dev = dev;
978 	strscpy(subdev->name, dev_name(dev), sizeof(subdev->name));
979 	subdev->flags |= V4L2_SUBDEV_FL_HAS_EVENTS | V4L2_SUBDEV_FL_HAS_DEVNODE;
980 	subdev->entity.ops = &xcsi2rxss_media_ops;
981 	v4l2_set_subdevdata(subdev, xcsi2rxss);
982 
983 	ret = media_entity_pads_init(&subdev->entity, XCSI_MEDIA_PADS,
984 				     xcsi2rxss->pads);
985 	if (ret < 0)
986 		goto error;
987 
988 	platform_set_drvdata(pdev, xcsi2rxss);
989 
990 	ret = v4l2_async_register_subdev(subdev);
991 	if (ret < 0) {
992 		dev_err(dev, "failed to register subdev\n");
993 		goto error;
994 	}
995 
996 	return 0;
997 error:
998 	media_entity_cleanup(&subdev->entity);
999 	mutex_destroy(&xcsi2rxss->lock);
1000 	clk_bulk_disable_unprepare(num_clks, xcsi2rxss->clks);
1001 err_clk_put:
1002 	clk_bulk_put(num_clks, xcsi2rxss->clks);
1003 	return ret;
1004 }
1005 
1006 static void xcsi2rxss_remove(struct platform_device *pdev)
1007 {
1008 	struct xcsi2rxss_state *xcsi2rxss = platform_get_drvdata(pdev);
1009 	struct v4l2_subdev *subdev = &xcsi2rxss->subdev;
1010 	int num_clks = ARRAY_SIZE(xcsi2rxss_clks);
1011 
1012 	v4l2_async_unregister_subdev(subdev);
1013 	media_entity_cleanup(&subdev->entity);
1014 	mutex_destroy(&xcsi2rxss->lock);
1015 	clk_bulk_disable_unprepare(num_clks, xcsi2rxss->clks);
1016 	clk_bulk_put(num_clks, xcsi2rxss->clks);
1017 }
1018 
1019 static const struct of_device_id xcsi2rxss_of_id_table[] = {
1020 	{ .compatible = "xlnx,mipi-csi2-rx-subsystem-5.0", },
1021 	{ }
1022 };
1023 MODULE_DEVICE_TABLE(of, xcsi2rxss_of_id_table);
1024 
1025 static struct platform_driver xcsi2rxss_driver = {
1026 	.driver = {
1027 		.name		= "xilinx-csi2rxss",
1028 		.of_match_table	= xcsi2rxss_of_id_table,
1029 	},
1030 	.probe			= xcsi2rxss_probe,
1031 	.remove_new		= xcsi2rxss_remove,
1032 };
1033 
1034 module_platform_driver(xcsi2rxss_driver);
1035 
1036 MODULE_AUTHOR("Vishal Sagar <vsagar@xilinx.com>");
1037 MODULE_DESCRIPTION("Xilinx MIPI CSI-2 Rx Subsystem Driver");
1038 MODULE_LICENSE("GPL v2");
1039