1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * TI OMAP4 ISS V4L2 Driver
4  *
5  * Copyright (C) 2012, Texas Instruments
6  *
7  * Author: Sergio Aguirre <sergio.a.aguirre@gmail.com>
8  */
9 
10 #include <linux/clk.h>
11 #include <linux/delay.h>
12 #include <linux/device.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/i2c.h>
15 #include <linux/interrupt.h>
16 #include <linux/mfd/syscon.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19 #include <linux/slab.h>
20 #include <linux/sched.h>
21 #include <linux/vmalloc.h>
22 
23 #include <media/v4l2-common.h>
24 #include <media/v4l2-device.h>
25 #include <media/v4l2-ctrls.h>
26 
27 #include "iss.h"
28 #include "iss_regs.h"
29 
30 #define ISS_PRINT_REGISTER(iss, name)\
31 	dev_dbg(iss->dev, "###ISS " #name "=0x%08x\n", \
32 		iss_reg_read(iss, OMAP4_ISS_MEM_TOP, ISS_##name))
33 
34 static void iss_print_status(struct iss_device *iss)
35 {
36 	dev_dbg(iss->dev, "-------------ISS HL Register dump-------------\n");
37 
38 	ISS_PRINT_REGISTER(iss, HL_REVISION);
39 	ISS_PRINT_REGISTER(iss, HL_SYSCONFIG);
40 	ISS_PRINT_REGISTER(iss, HL_IRQSTATUS(5));
41 	ISS_PRINT_REGISTER(iss, HL_IRQENABLE_SET(5));
42 	ISS_PRINT_REGISTER(iss, HL_IRQENABLE_CLR(5));
43 	ISS_PRINT_REGISTER(iss, CTRL);
44 	ISS_PRINT_REGISTER(iss, CLKCTRL);
45 	ISS_PRINT_REGISTER(iss, CLKSTAT);
46 
47 	dev_dbg(iss->dev, "-----------------------------------------------\n");
48 }
49 
50 /*
51  * omap4iss_flush - Post pending L3 bus writes by doing a register readback
52  * @iss: OMAP4 ISS device
53  *
54  * In order to force posting of pending writes, we need to write and
55  * readback the same register, in this case the revision register.
56  *
57  * See this link for reference:
58  *   https://www.mail-archive.com/linux-omap@vger.kernel.org/msg08149.html
59  */
60 static void omap4iss_flush(struct iss_device *iss)
61 {
62 	iss_reg_write(iss, OMAP4_ISS_MEM_TOP, ISS_HL_REVISION, 0);
63 	iss_reg_read(iss, OMAP4_ISS_MEM_TOP, ISS_HL_REVISION);
64 }
65 
66 /*
67  * iss_isp_enable_interrupts - Enable ISS ISP interrupts.
68  * @iss: OMAP4 ISS device
69  */
70 static void omap4iss_isp_enable_interrupts(struct iss_device *iss)
71 {
72 	static const u32 isp_irq = ISP5_IRQ_OCP_ERR |
73 				   ISP5_IRQ_RSZ_FIFO_IN_BLK_ERR |
74 				   ISP5_IRQ_RSZ_FIFO_OVF |
75 				   ISP5_IRQ_RSZ_INT_DMA |
76 				   ISP5_IRQ_ISIF_INT(0);
77 
78 	/* Enable ISP interrupts */
79 	iss_reg_write(iss, OMAP4_ISS_MEM_ISP_SYS1, ISP5_IRQSTATUS(0), isp_irq);
80 	iss_reg_write(iss, OMAP4_ISS_MEM_ISP_SYS1, ISP5_IRQENABLE_SET(0),
81 		      isp_irq);
82 }
83 
84 /*
85  * iss_isp_disable_interrupts - Disable ISS interrupts.
86  * @iss: OMAP4 ISS device
87  */
88 static void omap4iss_isp_disable_interrupts(struct iss_device *iss)
89 {
90 	iss_reg_write(iss, OMAP4_ISS_MEM_ISP_SYS1, ISP5_IRQENABLE_CLR(0), ~0);
91 }
92 
93 /*
94  * iss_enable_interrupts - Enable ISS interrupts.
95  * @iss: OMAP4 ISS device
96  */
97 static void iss_enable_interrupts(struct iss_device *iss)
98 {
99 	static const u32 hl_irq = ISS_HL_IRQ_CSIA | ISS_HL_IRQ_CSIB
100 				| ISS_HL_IRQ_ISP(0);
101 
102 	/* Enable HL interrupts */
103 	iss_reg_write(iss, OMAP4_ISS_MEM_TOP, ISS_HL_IRQSTATUS(5), hl_irq);
104 	iss_reg_write(iss, OMAP4_ISS_MEM_TOP, ISS_HL_IRQENABLE_SET(5), hl_irq);
105 
106 	if (iss->regs[OMAP4_ISS_MEM_ISP_SYS1])
107 		omap4iss_isp_enable_interrupts(iss);
108 }
109 
110 /*
111  * iss_disable_interrupts - Disable ISS interrupts.
112  * @iss: OMAP4 ISS device
113  */
114 static void iss_disable_interrupts(struct iss_device *iss)
115 {
116 	if (iss->regs[OMAP4_ISS_MEM_ISP_SYS1])
117 		omap4iss_isp_disable_interrupts(iss);
118 
119 	iss_reg_write(iss, OMAP4_ISS_MEM_TOP, ISS_HL_IRQENABLE_CLR(5), ~0);
120 }
121 
122 int omap4iss_get_external_info(struct iss_pipeline *pipe,
123 			       struct media_link *link)
124 {
125 	struct iss_device *iss =
126 		container_of(pipe, struct iss_video, pipe)->iss;
127 	struct v4l2_subdev_format fmt;
128 	struct v4l2_ctrl *ctrl;
129 	int ret;
130 
131 	if (!pipe->external)
132 		return 0;
133 
134 	if (pipe->external_rate)
135 		return 0;
136 
137 	memset(&fmt, 0, sizeof(fmt));
138 
139 	fmt.pad = link->source->index;
140 	fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
141 	ret = v4l2_subdev_call(media_entity_to_v4l2_subdev(link->sink->entity),
142 			       pad, get_fmt, NULL, &fmt);
143 	if (ret < 0)
144 		return -EPIPE;
145 
146 	pipe->external_bpp = omap4iss_video_format_info(fmt.format.code)->bpp;
147 
148 	ctrl = v4l2_ctrl_find(pipe->external->ctrl_handler,
149 			      V4L2_CID_PIXEL_RATE);
150 	if (!ctrl) {
151 		dev_warn(iss->dev, "no pixel rate control in subdev %s\n",
152 			 pipe->external->name);
153 		return -EPIPE;
154 	}
155 
156 	pipe->external_rate = v4l2_ctrl_g_ctrl_int64(ctrl);
157 
158 	return 0;
159 }
160 
161 /*
162  * Configure the bridge. Valid inputs are
163  *
164  * IPIPEIF_INPUT_CSI2A: CSI2a receiver
165  * IPIPEIF_INPUT_CSI2B: CSI2b receiver
166  *
167  * The bridge and lane shifter are configured according to the selected input
168  * and the ISP platform data.
169  */
170 void omap4iss_configure_bridge(struct iss_device *iss,
171 			       enum ipipeif_input_entity input)
172 {
173 	u32 issctrl_val;
174 	u32 isp5ctrl_val;
175 
176 	issctrl_val = iss_reg_read(iss, OMAP4_ISS_MEM_TOP, ISS_CTRL);
177 	issctrl_val &= ~ISS_CTRL_INPUT_SEL_MASK;
178 	issctrl_val &= ~ISS_CTRL_CLK_DIV_MASK;
179 
180 	isp5ctrl_val = iss_reg_read(iss, OMAP4_ISS_MEM_ISP_SYS1, ISP5_CTRL);
181 
182 	switch (input) {
183 	case IPIPEIF_INPUT_CSI2A:
184 		issctrl_val |= ISS_CTRL_INPUT_SEL_CSI2A;
185 		break;
186 
187 	case IPIPEIF_INPUT_CSI2B:
188 		issctrl_val |= ISS_CTRL_INPUT_SEL_CSI2B;
189 		break;
190 
191 	default:
192 		return;
193 	}
194 
195 	issctrl_val |= ISS_CTRL_SYNC_DETECT_VS_RAISING;
196 
197 	isp5ctrl_val |= ISP5_CTRL_VD_PULSE_EXT | ISP5_CTRL_PSYNC_CLK_SEL |
198 			ISP5_CTRL_SYNC_ENABLE;
199 
200 	iss_reg_write(iss, OMAP4_ISS_MEM_TOP, ISS_CTRL, issctrl_val);
201 	iss_reg_write(iss, OMAP4_ISS_MEM_ISP_SYS1, ISP5_CTRL, isp5ctrl_val);
202 }
203 
204 #ifdef ISS_ISR_DEBUG
205 static void iss_isr_dbg(struct iss_device *iss, u32 irqstatus)
206 {
207 	static const char * const name[] = {
208 		"ISP_0",
209 		"ISP_1",
210 		"ISP_2",
211 		"ISP_3",
212 		"CSIA",
213 		"CSIB",
214 		"CCP2_0",
215 		"CCP2_1",
216 		"CCP2_2",
217 		"CCP2_3",
218 		"CBUFF",
219 		"BTE",
220 		"SIMCOP_0",
221 		"SIMCOP_1",
222 		"SIMCOP_2",
223 		"SIMCOP_3",
224 		"CCP2_8",
225 		"HS_VS",
226 		"18",
227 		"19",
228 		"20",
229 		"21",
230 		"22",
231 		"23",
232 		"24",
233 		"25",
234 		"26",
235 		"27",
236 		"28",
237 		"29",
238 		"30",
239 		"31",
240 	};
241 	unsigned int i;
242 
243 	dev_dbg(iss->dev, "ISS IRQ: ");
244 
245 	for (i = 0; i < ARRAY_SIZE(name); i++) {
246 		if ((1 << i) & irqstatus)
247 			pr_cont("%s ", name[i]);
248 	}
249 	pr_cont("\n");
250 }
251 
252 static void iss_isp_isr_dbg(struct iss_device *iss, u32 irqstatus)
253 {
254 	static const char * const name[] = {
255 		"ISIF_0",
256 		"ISIF_1",
257 		"ISIF_2",
258 		"ISIF_3",
259 		"IPIPEREQ",
260 		"IPIPELAST_PIX",
261 		"IPIPEDMA",
262 		"IPIPEBSC",
263 		"IPIPEHST",
264 		"IPIPEIF",
265 		"AEW",
266 		"AF",
267 		"H3A",
268 		"RSZ_REG",
269 		"RSZ_LAST_PIX",
270 		"RSZ_DMA",
271 		"RSZ_CYC_RZA",
272 		"RSZ_CYC_RZB",
273 		"RSZ_FIFO_OVF",
274 		"RSZ_FIFO_IN_BLK_ERR",
275 		"20",
276 		"21",
277 		"RSZ_EOF0",
278 		"RSZ_EOF1",
279 		"H3A_EOF",
280 		"IPIPE_EOF",
281 		"26",
282 		"IPIPE_DPC_INI",
283 		"IPIPE_DPC_RNEW0",
284 		"IPIPE_DPC_RNEW1",
285 		"30",
286 		"OCP_ERR",
287 	};
288 	unsigned int i;
289 
290 	dev_dbg(iss->dev, "ISP IRQ: ");
291 
292 	for (i = 0; i < ARRAY_SIZE(name); i++) {
293 		if ((1 << i) & irqstatus)
294 			pr_cont("%s ", name[i]);
295 	}
296 	pr_cont("\n");
297 }
298 #endif
299 
300 /*
301  * iss_isr - Interrupt Service Routine for ISS module.
302  * @irq: Not used currently.
303  * @_iss: Pointer to the OMAP4 ISS device
304  *
305  * Handles the corresponding callback if plugged in.
306  *
307  * Returns IRQ_HANDLED when IRQ was correctly handled, or IRQ_NONE when the
308  * IRQ wasn't handled.
309  */
310 static irqreturn_t iss_isr(int irq, void *_iss)
311 {
312 	static const u32 ipipeif_events = ISP5_IRQ_IPIPEIF_IRQ |
313 					  ISP5_IRQ_ISIF_INT(0);
314 	static const u32 resizer_events = ISP5_IRQ_RSZ_FIFO_IN_BLK_ERR |
315 					  ISP5_IRQ_RSZ_FIFO_OVF |
316 					  ISP5_IRQ_RSZ_INT_DMA;
317 	struct iss_device *iss = _iss;
318 	u32 irqstatus;
319 
320 	irqstatus = iss_reg_read(iss, OMAP4_ISS_MEM_TOP, ISS_HL_IRQSTATUS(5));
321 	iss_reg_write(iss, OMAP4_ISS_MEM_TOP, ISS_HL_IRQSTATUS(5), irqstatus);
322 
323 	if (irqstatus & ISS_HL_IRQ_CSIA)
324 		omap4iss_csi2_isr(&iss->csi2a);
325 
326 	if (irqstatus & ISS_HL_IRQ_CSIB)
327 		omap4iss_csi2_isr(&iss->csi2b);
328 
329 	if (irqstatus & ISS_HL_IRQ_ISP(0)) {
330 		u32 isp_irqstatus = iss_reg_read(iss, OMAP4_ISS_MEM_ISP_SYS1,
331 						 ISP5_IRQSTATUS(0));
332 		iss_reg_write(iss, OMAP4_ISS_MEM_ISP_SYS1, ISP5_IRQSTATUS(0),
333 			      isp_irqstatus);
334 
335 		if (isp_irqstatus & ISP5_IRQ_OCP_ERR)
336 			dev_dbg(iss->dev, "ISP5 OCP Error!\n");
337 
338 		if (isp_irqstatus & ipipeif_events) {
339 			omap4iss_ipipeif_isr(&iss->ipipeif,
340 					     isp_irqstatus & ipipeif_events);
341 		}
342 
343 		if (isp_irqstatus & resizer_events)
344 			omap4iss_resizer_isr(&iss->resizer,
345 					     isp_irqstatus & resizer_events);
346 
347 #ifdef ISS_ISR_DEBUG
348 		iss_isp_isr_dbg(iss, isp_irqstatus);
349 #endif
350 	}
351 
352 	omap4iss_flush(iss);
353 
354 #ifdef ISS_ISR_DEBUG
355 	iss_isr_dbg(iss, irqstatus);
356 #endif
357 
358 	return IRQ_HANDLED;
359 }
360 
361 static const struct media_device_ops iss_media_ops = {
362 	.link_notify = v4l2_pipeline_link_notify,
363 };
364 
365 /* -----------------------------------------------------------------------------
366  * Pipeline stream management
367  */
368 
369 /*
370  * iss_pipeline_disable - Disable streaming on a pipeline
371  * @pipe: ISS pipeline
372  * @until: entity at which to stop pipeline walk
373  *
374  * Walk the entities chain starting at the pipeline output video node and stop
375  * all modules in the chain. Wait synchronously for the modules to be stopped if
376  * necessary.
377  *
378  * If the until argument isn't NULL, stop the pipeline walk when reaching the
379  * until entity. This is used to disable a partially started pipeline due to a
380  * subdev start error.
381  */
382 static int iss_pipeline_disable(struct iss_pipeline *pipe,
383 				struct media_entity *until)
384 {
385 	struct iss_device *iss = pipe->output->iss;
386 	struct media_entity *entity;
387 	struct media_pad *pad;
388 	struct v4l2_subdev *subdev;
389 	int failure = 0;
390 	int ret;
391 
392 	entity = &pipe->output->video.entity;
393 	while (1) {
394 		pad = &entity->pads[0];
395 		if (!(pad->flags & MEDIA_PAD_FL_SINK))
396 			break;
397 
398 		pad = media_pad_remote_pad_first(pad);
399 		if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
400 			break;
401 
402 		entity = pad->entity;
403 		if (entity == until)
404 			break;
405 
406 		subdev = media_entity_to_v4l2_subdev(entity);
407 		ret = v4l2_subdev_call(subdev, video, s_stream, 0);
408 		if (ret < 0) {
409 			dev_warn(iss->dev, "%s: module stop timeout.\n",
410 				 subdev->name);
411 			/* If the entity failed to stopped, assume it has
412 			 * crashed. Mark it as such, the ISS will be reset when
413 			 * applications will release it.
414 			 */
415 			media_entity_enum_set(&iss->crashed, &subdev->entity);
416 			failure = -ETIMEDOUT;
417 		}
418 	}
419 
420 	return failure;
421 }
422 
423 /*
424  * iss_pipeline_enable - Enable streaming on a pipeline
425  * @pipe: ISS pipeline
426  * @mode: Stream mode (single shot or continuous)
427  *
428  * Walk the entities chain starting at the pipeline output video node and start
429  * all modules in the chain in the given mode.
430  *
431  * Return 0 if successful, or the return value of the failed video::s_stream
432  * operation otherwise.
433  */
434 static int iss_pipeline_enable(struct iss_pipeline *pipe,
435 			       enum iss_pipeline_stream_state mode)
436 {
437 	struct iss_device *iss = pipe->output->iss;
438 	struct media_entity *entity;
439 	struct media_pad *pad;
440 	struct v4l2_subdev *subdev;
441 	unsigned long flags;
442 	int ret;
443 
444 	/* If one of the entities in the pipeline has crashed it will not work
445 	 * properly. Refuse to start streaming in that case. This check must be
446 	 * performed before the loop below to avoid starting entities if the
447 	 * pipeline won't start anyway (those entities would then likely fail to
448 	 * stop, making the problem worse).
449 	 */
450 	if (media_entity_enum_intersects(&pipe->ent_enum, &iss->crashed))
451 		return -EIO;
452 
453 	spin_lock_irqsave(&pipe->lock, flags);
454 	pipe->state &= ~(ISS_PIPELINE_IDLE_INPUT | ISS_PIPELINE_IDLE_OUTPUT);
455 	spin_unlock_irqrestore(&pipe->lock, flags);
456 
457 	pipe->do_propagation = false;
458 
459 	mutex_lock(&iss->media_dev.graph_mutex);
460 
461 	entity = &pipe->output->video.entity;
462 	while (1) {
463 		pad = &entity->pads[0];
464 		if (!(pad->flags & MEDIA_PAD_FL_SINK))
465 			break;
466 
467 		pad = media_pad_remote_pad_first(pad);
468 		if (!pad || !is_media_entity_v4l2_subdev(pad->entity))
469 			break;
470 
471 		entity = pad->entity;
472 		subdev = media_entity_to_v4l2_subdev(entity);
473 
474 		ret = v4l2_subdev_call(subdev, video, s_stream, mode);
475 		if (ret < 0 && ret != -ENOIOCTLCMD) {
476 			iss_pipeline_disable(pipe, entity);
477 			mutex_unlock(&iss->media_dev.graph_mutex);
478 			return ret;
479 		}
480 
481 		if (subdev == &iss->csi2a.subdev ||
482 		    subdev == &iss->csi2b.subdev)
483 			pipe->do_propagation = true;
484 	}
485 
486 	mutex_unlock(&iss->media_dev.graph_mutex);
487 	iss_print_status(pipe->output->iss);
488 
489 	return 0;
490 }
491 
492 /*
493  * omap4iss_pipeline_set_stream - Enable/disable streaming on a pipeline
494  * @pipe: ISS pipeline
495  * @state: Stream state (stopped, single shot or continuous)
496  *
497  * Set the pipeline to the given stream state. Pipelines can be started in
498  * single-shot or continuous mode.
499  *
500  * Return 0 if successful, or the return value of the failed video::s_stream
501  * operation otherwise. The pipeline state is not updated when the operation
502  * fails, except when stopping the pipeline.
503  */
504 int omap4iss_pipeline_set_stream(struct iss_pipeline *pipe,
505 				 enum iss_pipeline_stream_state state)
506 {
507 	int ret;
508 
509 	if (state == ISS_PIPELINE_STREAM_STOPPED)
510 		ret = iss_pipeline_disable(pipe, NULL);
511 	else
512 		ret = iss_pipeline_enable(pipe, state);
513 
514 	if (ret == 0 || state == ISS_PIPELINE_STREAM_STOPPED)
515 		pipe->stream_state = state;
516 
517 	return ret;
518 }
519 
520 /*
521  * omap4iss_pipeline_cancel_stream - Cancel stream on a pipeline
522  * @pipe: ISS pipeline
523  *
524  * Cancelling a stream mark all buffers on all video nodes in the pipeline as
525  * erroneous and makes sure no new buffer can be queued. This function is called
526  * when a fatal error that prevents any further operation on the pipeline
527  * occurs.
528  */
529 void omap4iss_pipeline_cancel_stream(struct iss_pipeline *pipe)
530 {
531 	if (pipe->input)
532 		omap4iss_video_cancel_stream(pipe->input);
533 	if (pipe->output)
534 		omap4iss_video_cancel_stream(pipe->output);
535 }
536 
537 /*
538  * iss_pipeline_is_last - Verify if entity has an enabled link to the output
539  *			  video node
540  * @me: ISS module's media entity
541  *
542  * Returns 1 if the entity has an enabled link to the output video node or 0
543  * otherwise. It's true only while pipeline can have no more than one output
544  * node.
545  */
546 static int iss_pipeline_is_last(struct media_entity *me)
547 {
548 	struct iss_pipeline *pipe;
549 	struct media_pad *pad;
550 
551 	pipe = to_iss_pipeline(me);
552 	if (!pipe || pipe->stream_state == ISS_PIPELINE_STREAM_STOPPED)
553 		return 0;
554 	pad = media_pad_remote_pad_first(&pipe->output->pad);
555 	return pad->entity == me;
556 }
557 
558 static int iss_reset(struct iss_device *iss)
559 {
560 	unsigned int timeout;
561 
562 	iss_reg_set(iss, OMAP4_ISS_MEM_TOP, ISS_HL_SYSCONFIG,
563 		    ISS_HL_SYSCONFIG_SOFTRESET);
564 
565 	timeout = iss_poll_condition_timeout(
566 		!(iss_reg_read(iss, OMAP4_ISS_MEM_TOP, ISS_HL_SYSCONFIG) &
567 		ISS_HL_SYSCONFIG_SOFTRESET), 1000, 10, 100);
568 	if (timeout) {
569 		dev_err(iss->dev, "ISS reset timeout\n");
570 		return -ETIMEDOUT;
571 	}
572 
573 	media_entity_enum_zero(&iss->crashed);
574 
575 	return 0;
576 }
577 
578 static int iss_isp_reset(struct iss_device *iss)
579 {
580 	unsigned int timeout;
581 
582 	/* Fist, ensure that the ISP is IDLE (no transactions happening) */
583 	iss_reg_update(iss, OMAP4_ISS_MEM_ISP_SYS1, ISP5_SYSCONFIG,
584 		       ISP5_SYSCONFIG_STANDBYMODE_MASK,
585 		       ISP5_SYSCONFIG_STANDBYMODE_SMART);
586 
587 	iss_reg_set(iss, OMAP4_ISS_MEM_ISP_SYS1, ISP5_CTRL, ISP5_CTRL_MSTANDBY);
588 
589 	timeout = iss_poll_condition_timeout(
590 		iss_reg_read(iss, OMAP4_ISS_MEM_ISP_SYS1, ISP5_CTRL) &
591 		ISP5_CTRL_MSTANDBY_WAIT, 1000000, 1000, 1500);
592 	if (timeout) {
593 		dev_err(iss->dev, "ISP5 standby timeout\n");
594 		return -ETIMEDOUT;
595 	}
596 
597 	/* Now finally, do the reset */
598 	iss_reg_set(iss, OMAP4_ISS_MEM_ISP_SYS1, ISP5_SYSCONFIG,
599 		    ISP5_SYSCONFIG_SOFTRESET);
600 
601 	timeout = iss_poll_condition_timeout(
602 		!(iss_reg_read(iss, OMAP4_ISS_MEM_ISP_SYS1, ISP5_SYSCONFIG) &
603 		ISP5_SYSCONFIG_SOFTRESET), 1000000, 1000, 1500);
604 	if (timeout) {
605 		dev_err(iss->dev, "ISP5 reset timeout\n");
606 		return -ETIMEDOUT;
607 	}
608 
609 	return 0;
610 }
611 
612 /*
613  * iss_module_sync_idle - Helper to sync module with its idle state
614  * @me: ISS submodule's media entity
615  * @wait: ISS submodule's wait queue for streamoff/interrupt synchronization
616  * @stopping: flag which tells module wants to stop
617  *
618  * This function checks if ISS submodule needs to wait for next interrupt. If
619  * yes, makes the caller to sleep while waiting for such event.
620  */
621 int omap4iss_module_sync_idle(struct media_entity *me, wait_queue_head_t *wait,
622 			      atomic_t *stopping)
623 {
624 	struct iss_pipeline *pipe = to_iss_pipeline(me);
625 	struct iss_video *video = pipe->output;
626 	unsigned long flags;
627 
628 	if (pipe->stream_state == ISS_PIPELINE_STREAM_STOPPED ||
629 	    (pipe->stream_state == ISS_PIPELINE_STREAM_SINGLESHOT &&
630 	     !iss_pipeline_ready(pipe)))
631 		return 0;
632 
633 	/*
634 	 * atomic_set() doesn't include memory barrier on ARM platform for SMP
635 	 * scenario. We'll call it here to avoid race conditions.
636 	 */
637 	atomic_set(stopping, 1);
638 	smp_wmb();
639 
640 	/*
641 	 * If module is the last one, it's writing to memory. In this case,
642 	 * it's necessary to check if the module is already paused due to
643 	 * DMA queue underrun or if it has to wait for next interrupt to be
644 	 * idle.
645 	 * If it isn't the last one, the function won't sleep but *stopping
646 	 * will still be set to warn next submodule caller's interrupt the
647 	 * module wants to be idle.
648 	 */
649 	if (!iss_pipeline_is_last(me))
650 		return 0;
651 
652 	spin_lock_irqsave(&video->qlock, flags);
653 	if (video->dmaqueue_flags & ISS_VIDEO_DMAQUEUE_UNDERRUN) {
654 		spin_unlock_irqrestore(&video->qlock, flags);
655 		atomic_set(stopping, 0);
656 		smp_wmb();
657 		return 0;
658 	}
659 	spin_unlock_irqrestore(&video->qlock, flags);
660 	if (!wait_event_timeout(*wait, !atomic_read(stopping),
661 				msecs_to_jiffies(1000))) {
662 		atomic_set(stopping, 0);
663 		smp_wmb();
664 		return -ETIMEDOUT;
665 	}
666 
667 	return 0;
668 }
669 
670 /*
671  * omap4iss_module_sync_is_stopped - Helper to verify if module was stopping
672  * @wait: ISS submodule's wait queue for streamoff/interrupt synchronization
673  * @stopping: flag which tells module wants to stop
674  *
675  * This function checks if ISS submodule was stopping. In case of yes, it
676  * notices the caller by setting stopping to 0 and waking up the wait queue.
677  * Returns 1 if it was stopping or 0 otherwise.
678  */
679 int omap4iss_module_sync_is_stopping(wait_queue_head_t *wait,
680 				     atomic_t *stopping)
681 {
682 	if (atomic_cmpxchg(stopping, 1, 0)) {
683 		wake_up(wait);
684 		return 1;
685 	}
686 
687 	return 0;
688 }
689 
690 /* --------------------------------------------------------------------------
691  * Clock management
692  */
693 
694 #define ISS_CLKCTRL_MASK	(ISS_CLKCTRL_CSI2_A |\
695 				 ISS_CLKCTRL_CSI2_B |\
696 				 ISS_CLKCTRL_ISP)
697 
698 static int __iss_subclk_update(struct iss_device *iss)
699 {
700 	u32 clk = 0;
701 	int ret = 0, timeout = 1000;
702 
703 	if (iss->subclk_resources & OMAP4_ISS_SUBCLK_CSI2_A)
704 		clk |= ISS_CLKCTRL_CSI2_A;
705 
706 	if (iss->subclk_resources & OMAP4_ISS_SUBCLK_CSI2_B)
707 		clk |= ISS_CLKCTRL_CSI2_B;
708 
709 	if (iss->subclk_resources & OMAP4_ISS_SUBCLK_ISP)
710 		clk |= ISS_CLKCTRL_ISP;
711 
712 	iss_reg_update(iss, OMAP4_ISS_MEM_TOP, ISS_CLKCTRL,
713 		       ISS_CLKCTRL_MASK, clk);
714 
715 	/* Wait for HW assertion */
716 	while (--timeout > 0) {
717 		udelay(1);
718 		if ((iss_reg_read(iss, OMAP4_ISS_MEM_TOP, ISS_CLKSTAT) &
719 		    ISS_CLKCTRL_MASK) == clk)
720 			break;
721 	}
722 
723 	if (!timeout)
724 		ret = -EBUSY;
725 
726 	return ret;
727 }
728 
729 int omap4iss_subclk_enable(struct iss_device *iss,
730 			   enum iss_subclk_resource res)
731 {
732 	iss->subclk_resources |= res;
733 
734 	return __iss_subclk_update(iss);
735 }
736 
737 int omap4iss_subclk_disable(struct iss_device *iss,
738 			    enum iss_subclk_resource res)
739 {
740 	iss->subclk_resources &= ~res;
741 
742 	return __iss_subclk_update(iss);
743 }
744 
745 #define ISS_ISP5_CLKCTRL_MASK	(ISP5_CTRL_BL_CLK_ENABLE |\
746 				 ISP5_CTRL_ISIF_CLK_ENABLE |\
747 				 ISP5_CTRL_H3A_CLK_ENABLE |\
748 				 ISP5_CTRL_RSZ_CLK_ENABLE |\
749 				 ISP5_CTRL_IPIPE_CLK_ENABLE |\
750 				 ISP5_CTRL_IPIPEIF_CLK_ENABLE)
751 
752 static void __iss_isp_subclk_update(struct iss_device *iss)
753 {
754 	u32 clk = 0;
755 
756 	if (iss->isp_subclk_resources & OMAP4_ISS_ISP_SUBCLK_ISIF)
757 		clk |= ISP5_CTRL_ISIF_CLK_ENABLE;
758 
759 	if (iss->isp_subclk_resources & OMAP4_ISS_ISP_SUBCLK_H3A)
760 		clk |= ISP5_CTRL_H3A_CLK_ENABLE;
761 
762 	if (iss->isp_subclk_resources & OMAP4_ISS_ISP_SUBCLK_RSZ)
763 		clk |= ISP5_CTRL_RSZ_CLK_ENABLE;
764 
765 	if (iss->isp_subclk_resources & OMAP4_ISS_ISP_SUBCLK_IPIPE)
766 		clk |= ISP5_CTRL_IPIPE_CLK_ENABLE;
767 
768 	if (iss->isp_subclk_resources & OMAP4_ISS_ISP_SUBCLK_IPIPEIF)
769 		clk |= ISP5_CTRL_IPIPEIF_CLK_ENABLE;
770 
771 	if (clk)
772 		clk |= ISP5_CTRL_BL_CLK_ENABLE;
773 
774 	iss_reg_update(iss, OMAP4_ISS_MEM_ISP_SYS1, ISP5_CTRL,
775 		       ISS_ISP5_CLKCTRL_MASK, clk);
776 }
777 
778 void omap4iss_isp_subclk_enable(struct iss_device *iss,
779 				enum iss_isp_subclk_resource res)
780 {
781 	iss->isp_subclk_resources |= res;
782 
783 	__iss_isp_subclk_update(iss);
784 }
785 
786 void omap4iss_isp_subclk_disable(struct iss_device *iss,
787 				 enum iss_isp_subclk_resource res)
788 {
789 	iss->isp_subclk_resources &= ~res;
790 
791 	__iss_isp_subclk_update(iss);
792 }
793 
794 /*
795  * iss_enable_clocks - Enable ISS clocks
796  * @iss: OMAP4 ISS device
797  *
798  * Return 0 if successful, or clk_enable return value if any of tthem fails.
799  */
800 static int iss_enable_clocks(struct iss_device *iss)
801 {
802 	int ret;
803 
804 	ret = clk_enable(iss->iss_fck);
805 	if (ret) {
806 		dev_err(iss->dev, "clk_enable iss_fck failed\n");
807 		return ret;
808 	}
809 
810 	ret = clk_enable(iss->iss_ctrlclk);
811 	if (ret) {
812 		dev_err(iss->dev, "clk_enable iss_ctrlclk failed\n");
813 		clk_disable(iss->iss_fck);
814 		return ret;
815 	}
816 
817 	return 0;
818 }
819 
820 /*
821  * iss_disable_clocks - Disable ISS clocks
822  * @iss: OMAP4 ISS device
823  */
824 static void iss_disable_clocks(struct iss_device *iss)
825 {
826 	clk_disable(iss->iss_ctrlclk);
827 	clk_disable(iss->iss_fck);
828 }
829 
830 static int iss_get_clocks(struct iss_device *iss)
831 {
832 	iss->iss_fck = devm_clk_get(iss->dev, "iss_fck");
833 	if (IS_ERR(iss->iss_fck)) {
834 		dev_err(iss->dev, "Unable to get iss_fck clock info\n");
835 		return PTR_ERR(iss->iss_fck);
836 	}
837 
838 	iss->iss_ctrlclk = devm_clk_get(iss->dev, "iss_ctrlclk");
839 	if (IS_ERR(iss->iss_ctrlclk)) {
840 		dev_err(iss->dev, "Unable to get iss_ctrlclk clock info\n");
841 		return PTR_ERR(iss->iss_ctrlclk);
842 	}
843 
844 	return 0;
845 }
846 
847 /*
848  * omap4iss_get - Acquire the ISS resource.
849  *
850  * Initializes the clocks for the first acquire.
851  *
852  * Increment the reference count on the ISS. If the first reference is taken,
853  * enable clocks and power-up all submodules.
854  *
855  * Return a pointer to the ISS device structure, or NULL if an error occurred.
856  */
857 struct iss_device *omap4iss_get(struct iss_device *iss)
858 {
859 	struct iss_device *__iss = iss;
860 
861 	if (!iss)
862 		return NULL;
863 
864 	mutex_lock(&iss->iss_mutex);
865 	if (iss->ref_count > 0)
866 		goto out;
867 
868 	if (iss_enable_clocks(iss) < 0) {
869 		__iss = NULL;
870 		goto out;
871 	}
872 
873 	iss_enable_interrupts(iss);
874 
875 out:
876 	if (__iss)
877 		iss->ref_count++;
878 	mutex_unlock(&iss->iss_mutex);
879 
880 	return __iss;
881 }
882 
883 /*
884  * omap4iss_put - Release the ISS
885  *
886  * Decrement the reference count on the ISS. If the last reference is released,
887  * power-down all submodules, disable clocks and free temporary buffers.
888  */
889 void omap4iss_put(struct iss_device *iss)
890 {
891 	if (!iss)
892 		return;
893 
894 	mutex_lock(&iss->iss_mutex);
895 	WARN_ON(iss->ref_count == 0);
896 	if (--iss->ref_count == 0) {
897 		iss_disable_interrupts(iss);
898 		/* Reset the ISS if an entity has failed to stop. This is the
899 		 * only way to recover from such conditions, although it would
900 		 * be worth investigating whether resetting the ISP only can't
901 		 * fix the problem in some cases.
902 		 */
903 		if (!media_entity_enum_empty(&iss->crashed))
904 			iss_reset(iss);
905 		iss_disable_clocks(iss);
906 	}
907 	mutex_unlock(&iss->iss_mutex);
908 }
909 
910 static int iss_map_mem_resource(struct platform_device *pdev,
911 				struct iss_device *iss,
912 				enum iss_mem_resources res)
913 {
914 	iss->regs[res] = devm_platform_ioremap_resource(pdev, res);
915 
916 	return PTR_ERR_OR_ZERO(iss->regs[res]);
917 }
918 
919 static void iss_unregister_entities(struct iss_device *iss)
920 {
921 	omap4iss_resizer_unregister_entities(&iss->resizer);
922 	omap4iss_ipipe_unregister_entities(&iss->ipipe);
923 	omap4iss_ipipeif_unregister_entities(&iss->ipipeif);
924 	omap4iss_csi2_unregister_entities(&iss->csi2a);
925 	omap4iss_csi2_unregister_entities(&iss->csi2b);
926 
927 	v4l2_device_unregister(&iss->v4l2_dev);
928 	media_device_unregister(&iss->media_dev);
929 }
930 
931 /*
932  * iss_register_subdev_group - Register a group of subdevices
933  * @iss: OMAP4 ISS device
934  * @board_info: I2C subdevs board information array
935  *
936  * Register all I2C subdevices in the board_info array. The array must be
937  * terminated by a NULL entry, and the first entry must be the sensor.
938  *
939  * Return a pointer to the sensor media entity if it has been successfully
940  * registered, or NULL otherwise.
941  */
942 static struct v4l2_subdev *
943 iss_register_subdev_group(struct iss_device *iss,
944 			  struct iss_subdev_i2c_board_info *board_info)
945 {
946 	struct v4l2_subdev *sensor = NULL;
947 	unsigned int first;
948 
949 	if (!board_info->board_info)
950 		return NULL;
951 
952 	for (first = 1; board_info->board_info; ++board_info, first = 0) {
953 		struct v4l2_subdev *subdev;
954 		struct i2c_adapter *adapter;
955 
956 		adapter = i2c_get_adapter(board_info->i2c_adapter_id);
957 		if (!adapter) {
958 			dev_err(iss->dev,
959 				"%s: Unable to get I2C adapter %d for device %s\n",
960 				__func__, board_info->i2c_adapter_id,
961 				board_info->board_info->type);
962 			continue;
963 		}
964 
965 		subdev = v4l2_i2c_new_subdev_board(&iss->v4l2_dev, adapter,
966 						   board_info->board_info, NULL);
967 		if (!subdev) {
968 			dev_err(iss->dev, "Unable to register subdev %s\n",
969 				board_info->board_info->type);
970 			continue;
971 		}
972 
973 		if (first)
974 			sensor = subdev;
975 	}
976 
977 	return sensor;
978 }
979 
980 static int iss_register_entities(struct iss_device *iss)
981 {
982 	struct iss_platform_data *pdata = iss->pdata;
983 	struct iss_v4l2_subdevs_group *subdevs;
984 	int ret;
985 
986 	iss->media_dev.dev = iss->dev;
987 	strscpy(iss->media_dev.model, "TI OMAP4 ISS",
988 		sizeof(iss->media_dev.model));
989 	iss->media_dev.hw_revision = iss->revision;
990 	iss->media_dev.ops = &iss_media_ops;
991 	ret = media_device_register(&iss->media_dev);
992 	if (ret < 0) {
993 		dev_err(iss->dev, "Media device registration failed (%d)\n",
994 			ret);
995 		return ret;
996 	}
997 
998 	iss->v4l2_dev.mdev = &iss->media_dev;
999 	ret = v4l2_device_register(iss->dev, &iss->v4l2_dev);
1000 	if (ret < 0) {
1001 		dev_err(iss->dev, "V4L2 device registration failed (%d)\n",
1002 			ret);
1003 		goto done;
1004 	}
1005 
1006 	/* Register internal entities */
1007 	ret = omap4iss_csi2_register_entities(&iss->csi2a, &iss->v4l2_dev);
1008 	if (ret < 0)
1009 		goto done;
1010 
1011 	ret = omap4iss_csi2_register_entities(&iss->csi2b, &iss->v4l2_dev);
1012 	if (ret < 0)
1013 		goto done;
1014 
1015 	ret = omap4iss_ipipeif_register_entities(&iss->ipipeif, &iss->v4l2_dev);
1016 	if (ret < 0)
1017 		goto done;
1018 
1019 	ret = omap4iss_ipipe_register_entities(&iss->ipipe, &iss->v4l2_dev);
1020 	if (ret < 0)
1021 		goto done;
1022 
1023 	ret = omap4iss_resizer_register_entities(&iss->resizer, &iss->v4l2_dev);
1024 	if (ret < 0)
1025 		goto done;
1026 
1027 	/* Register external entities */
1028 	for (subdevs = pdata->subdevs; subdevs && subdevs->subdevs; ++subdevs) {
1029 		struct v4l2_subdev *sensor;
1030 		struct media_entity *input;
1031 		unsigned int flags;
1032 		unsigned int pad;
1033 
1034 		sensor = iss_register_subdev_group(iss, subdevs->subdevs);
1035 		if (!sensor)
1036 			continue;
1037 
1038 		sensor->host_priv = subdevs;
1039 
1040 		/* Connect the sensor to the correct interface module.
1041 		 * CSI2a receiver through CSIPHY1, or
1042 		 * CSI2b receiver through CSIPHY2
1043 		 */
1044 		switch (subdevs->interface) {
1045 		case ISS_INTERFACE_CSI2A_PHY1:
1046 			input = &iss->csi2a.subdev.entity;
1047 			pad = CSI2_PAD_SINK;
1048 			flags = MEDIA_LNK_FL_IMMUTABLE
1049 			      | MEDIA_LNK_FL_ENABLED;
1050 			break;
1051 
1052 		case ISS_INTERFACE_CSI2B_PHY2:
1053 			input = &iss->csi2b.subdev.entity;
1054 			pad = CSI2_PAD_SINK;
1055 			flags = MEDIA_LNK_FL_IMMUTABLE
1056 			      | MEDIA_LNK_FL_ENABLED;
1057 			break;
1058 
1059 		default:
1060 			dev_err(iss->dev, "invalid interface type %u\n",
1061 				subdevs->interface);
1062 			ret = -EINVAL;
1063 			goto done;
1064 		}
1065 
1066 		ret = media_create_pad_link(&sensor->entity, 0, input, pad,
1067 					    flags);
1068 		if (ret < 0)
1069 			goto done;
1070 	}
1071 
1072 	ret = v4l2_device_register_subdev_nodes(&iss->v4l2_dev);
1073 
1074 done:
1075 	if (ret < 0)
1076 		iss_unregister_entities(iss);
1077 
1078 	return ret;
1079 }
1080 
1081 /*
1082  * iss_create_links() - Pads links creation for the subdevices
1083  * @iss : Pointer to ISS device
1084  *
1085  * return negative error code or zero on success
1086  */
1087 static int iss_create_links(struct iss_device *iss)
1088 {
1089 	int ret;
1090 
1091 	ret = omap4iss_csi2_create_links(iss);
1092 	if (ret < 0) {
1093 		dev_err(iss->dev, "CSI2 pads links creation failed\n");
1094 		return ret;
1095 	}
1096 
1097 	ret = omap4iss_ipipeif_create_links(iss);
1098 	if (ret < 0) {
1099 		dev_err(iss->dev, "ISP IPIPEIF pads links creation failed\n");
1100 		return ret;
1101 	}
1102 
1103 	ret = omap4iss_resizer_create_links(iss);
1104 	if (ret < 0) {
1105 		dev_err(iss->dev, "ISP RESIZER pads links creation failed\n");
1106 		return ret;
1107 	}
1108 
1109 	/* Connect the submodules. */
1110 	ret = media_create_pad_link(
1111 			&iss->csi2a.subdev.entity, CSI2_PAD_SOURCE,
1112 			&iss->ipipeif.subdev.entity, IPIPEIF_PAD_SINK, 0);
1113 	if (ret < 0)
1114 		return ret;
1115 
1116 	ret = media_create_pad_link(
1117 			&iss->csi2b.subdev.entity, CSI2_PAD_SOURCE,
1118 			&iss->ipipeif.subdev.entity, IPIPEIF_PAD_SINK, 0);
1119 	if (ret < 0)
1120 		return ret;
1121 
1122 	ret = media_create_pad_link(
1123 			&iss->ipipeif.subdev.entity, IPIPEIF_PAD_SOURCE_VP,
1124 			&iss->resizer.subdev.entity, RESIZER_PAD_SINK, 0);
1125 	if (ret < 0)
1126 		return ret;
1127 
1128 	ret = media_create_pad_link(
1129 			&iss->ipipeif.subdev.entity, IPIPEIF_PAD_SOURCE_VP,
1130 			&iss->ipipe.subdev.entity, IPIPE_PAD_SINK, 0);
1131 	if (ret < 0)
1132 		return ret;
1133 
1134 	ret = media_create_pad_link(
1135 			&iss->ipipe.subdev.entity, IPIPE_PAD_SOURCE_VP,
1136 			&iss->resizer.subdev.entity, RESIZER_PAD_SINK, 0);
1137 	if (ret < 0)
1138 		return ret;
1139 
1140 	return 0;
1141 };
1142 
1143 static void iss_cleanup_modules(struct iss_device *iss)
1144 {
1145 	omap4iss_csi2_cleanup(iss);
1146 	omap4iss_ipipeif_cleanup(iss);
1147 	omap4iss_ipipe_cleanup(iss);
1148 	omap4iss_resizer_cleanup(iss);
1149 }
1150 
1151 static int iss_initialize_modules(struct iss_device *iss)
1152 {
1153 	int ret;
1154 
1155 	ret = omap4iss_csiphy_init(iss);
1156 	if (ret < 0) {
1157 		dev_err(iss->dev, "CSI PHY initialization failed\n");
1158 		goto error_csiphy;
1159 	}
1160 
1161 	ret = omap4iss_csi2_init(iss);
1162 	if (ret < 0) {
1163 		dev_err(iss->dev, "CSI2 initialization failed\n");
1164 		goto error_csi2;
1165 	}
1166 
1167 	ret = omap4iss_ipipeif_init(iss);
1168 	if (ret < 0) {
1169 		dev_err(iss->dev, "ISP IPIPEIF initialization failed\n");
1170 		goto error_ipipeif;
1171 	}
1172 
1173 	ret = omap4iss_ipipe_init(iss);
1174 	if (ret < 0) {
1175 		dev_err(iss->dev, "ISP IPIPE initialization failed\n");
1176 		goto error_ipipe;
1177 	}
1178 
1179 	ret = omap4iss_resizer_init(iss);
1180 	if (ret < 0) {
1181 		dev_err(iss->dev, "ISP RESIZER initialization failed\n");
1182 		goto error_resizer;
1183 	}
1184 
1185 	return 0;
1186 
1187 error_resizer:
1188 	omap4iss_ipipe_cleanup(iss);
1189 error_ipipe:
1190 	omap4iss_ipipeif_cleanup(iss);
1191 error_ipipeif:
1192 	omap4iss_csi2_cleanup(iss);
1193 error_csi2:
1194 error_csiphy:
1195 	return ret;
1196 }
1197 
1198 static int iss_probe(struct platform_device *pdev)
1199 {
1200 	struct iss_platform_data *pdata = pdev->dev.platform_data;
1201 	struct iss_device *iss;
1202 	unsigned int i;
1203 	int ret;
1204 
1205 	if (!pdata)
1206 		return -EINVAL;
1207 
1208 	iss = devm_kzalloc(&pdev->dev, sizeof(*iss), GFP_KERNEL);
1209 	if (!iss)
1210 		return -ENOMEM;
1211 
1212 	mutex_init(&iss->iss_mutex);
1213 
1214 	iss->dev = &pdev->dev;
1215 	iss->pdata = pdata;
1216 
1217 	iss->raw_dmamask = DMA_BIT_MASK(32);
1218 	iss->dev->dma_mask = &iss->raw_dmamask;
1219 	iss->dev->coherent_dma_mask = DMA_BIT_MASK(32);
1220 
1221 	platform_set_drvdata(pdev, iss);
1222 
1223 	/*
1224 	 * TODO: When implementing DT support switch to syscon regmap lookup by
1225 	 * phandle.
1226 	 */
1227 	iss->syscon = syscon_regmap_lookup_by_compatible("syscon");
1228 	if (IS_ERR(iss->syscon)) {
1229 		ret = PTR_ERR(iss->syscon);
1230 		goto error;
1231 	}
1232 
1233 	/* Clocks */
1234 	ret = iss_map_mem_resource(pdev, iss, OMAP4_ISS_MEM_TOP);
1235 	if (ret < 0)
1236 		goto error;
1237 
1238 	ret = iss_get_clocks(iss);
1239 	if (ret < 0)
1240 		goto error;
1241 
1242 	if (!omap4iss_get(iss)) {
1243 		ret = -EINVAL;
1244 		goto error;
1245 	}
1246 
1247 	ret = iss_reset(iss);
1248 	if (ret < 0)
1249 		goto error_iss;
1250 
1251 	iss->revision = iss_reg_read(iss, OMAP4_ISS_MEM_TOP, ISS_HL_REVISION);
1252 	dev_info(iss->dev, "Revision %08x found\n", iss->revision);
1253 
1254 	for (i = 1; i < OMAP4_ISS_MEM_LAST; i++) {
1255 		ret = iss_map_mem_resource(pdev, iss, i);
1256 		if (ret)
1257 			goto error_iss;
1258 	}
1259 
1260 	/* Configure BTE BW_LIMITER field to max recommended value (1 GB) */
1261 	iss_reg_update(iss, OMAP4_ISS_MEM_BTE, BTE_CTRL,
1262 		       BTE_CTRL_BW_LIMITER_MASK,
1263 		       18 << BTE_CTRL_BW_LIMITER_SHIFT);
1264 
1265 	/* Perform ISP reset */
1266 	ret = omap4iss_subclk_enable(iss, OMAP4_ISS_SUBCLK_ISP);
1267 	if (ret < 0)
1268 		goto error_iss;
1269 
1270 	ret = iss_isp_reset(iss);
1271 	if (ret < 0)
1272 		goto error_iss;
1273 
1274 	dev_info(iss->dev, "ISP Revision %08x found\n",
1275 		 iss_reg_read(iss, OMAP4_ISS_MEM_ISP_SYS1, ISP5_REVISION));
1276 
1277 	/* Interrupt */
1278 	ret = platform_get_irq(pdev, 0);
1279 	if (ret <= 0) {
1280 		ret = -ENODEV;
1281 		goto error_iss;
1282 	}
1283 	iss->irq_num = ret;
1284 
1285 	if (devm_request_irq(iss->dev, iss->irq_num, iss_isr, IRQF_SHARED,
1286 			     "OMAP4 ISS", iss)) {
1287 		dev_err(iss->dev, "Unable to request IRQ\n");
1288 		ret = -EINVAL;
1289 		goto error_iss;
1290 	}
1291 
1292 	/* Entities */
1293 	ret = iss_initialize_modules(iss);
1294 	if (ret < 0)
1295 		goto error_iss;
1296 
1297 	ret = iss_register_entities(iss);
1298 	if (ret < 0)
1299 		goto error_modules;
1300 
1301 	ret = media_entity_enum_init(&iss->crashed, &iss->media_dev);
1302 	if (ret)
1303 		goto error_entities;
1304 
1305 	ret = iss_create_links(iss);
1306 	if (ret < 0)
1307 		goto error_entities;
1308 
1309 	omap4iss_put(iss);
1310 
1311 	return 0;
1312 
1313 error_entities:
1314 	iss_unregister_entities(iss);
1315 	media_entity_enum_cleanup(&iss->crashed);
1316 error_modules:
1317 	iss_cleanup_modules(iss);
1318 error_iss:
1319 	omap4iss_put(iss);
1320 error:
1321 	mutex_destroy(&iss->iss_mutex);
1322 
1323 	return ret;
1324 }
1325 
1326 static void iss_remove(struct platform_device *pdev)
1327 {
1328 	struct iss_device *iss = platform_get_drvdata(pdev);
1329 
1330 	iss_unregister_entities(iss);
1331 	media_entity_enum_cleanup(&iss->crashed);
1332 	iss_cleanup_modules(iss);
1333 }
1334 
1335 static const struct platform_device_id omap4iss_id_table[] = {
1336 	{ "omap4iss", 0 },
1337 	{ },
1338 };
1339 MODULE_DEVICE_TABLE(platform, omap4iss_id_table);
1340 
1341 static struct platform_driver iss_driver = {
1342 	.probe		= iss_probe,
1343 	.remove_new	= iss_remove,
1344 	.id_table	= omap4iss_id_table,
1345 	.driver = {
1346 		.name	= "omap4iss",
1347 	},
1348 };
1349 
1350 module_platform_driver(iss_driver);
1351 
1352 MODULE_DESCRIPTION("TI OMAP4 ISS driver");
1353 MODULE_AUTHOR("Sergio Aguirre <sergio.a.aguirre@gmail.com>");
1354 MODULE_LICENSE("GPL");
1355