1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Driver for STM32 Digital Camera Memory Interface Pixel Processor
4 *
5 * Copyright (C) STMicroelectronics SA 2023
6 * Authors: Hugues Fruchet <hugues.fruchet@foss.st.com>
7 *          Alain Volmat <alain.volmat@foss.st.com>
8 *          for STMicroelectronics.
9 */
10
11#include <linux/init.h>
12#include <linux/module.h>
13
14#include "dcmipp-common.h"
15
16/* Helper function to allocate and initialize pads */
17struct media_pad *dcmipp_pads_init(u16 num_pads, const unsigned long *pads_flags)
18{
19	struct media_pad *pads;
20	unsigned int i;
21
22	/* Allocate memory for the pads */
23	pads = kcalloc(num_pads, sizeof(*pads), GFP_KERNEL);
24	if (!pads)
25		return ERR_PTR(-ENOMEM);
26
27	/* Initialize the pads */
28	for (i = 0; i < num_pads; i++) {
29		pads[i].index = i;
30		pads[i].flags = pads_flags[i];
31	}
32
33	return pads;
34}
35
36static const struct media_entity_operations dcmipp_entity_ops = {
37	.link_validate = v4l2_subdev_link_validate,
38};
39
40int dcmipp_ent_sd_register(struct dcmipp_ent_device *ved,
41			   struct v4l2_subdev *sd,
42			   struct v4l2_device *v4l2_dev,
43			   const char *const name,
44			   u32 function,
45			   u16 num_pads,
46			   const unsigned long *pads_flag,
47			   const struct v4l2_subdev_internal_ops *sd_int_ops,
48			   const struct v4l2_subdev_ops *sd_ops,
49			   irq_handler_t handler,
50			   irq_handler_t thread_fn)
51{
52	int ret;
53
54	/* Allocate the pads. Should be released from the sd_int_op release */
55	ved->pads = dcmipp_pads_init(num_pads, pads_flag);
56	if (IS_ERR(ved->pads))
57		return PTR_ERR(ved->pads);
58
59	/* Fill the dcmipp_ent_device struct */
60	ved->ent = &sd->entity;
61
62	/* Initialize the subdev */
63	v4l2_subdev_init(sd, sd_ops);
64	sd->internal_ops = sd_int_ops;
65	sd->entity.function = function;
66	sd->entity.ops = &dcmipp_entity_ops;
67	sd->owner = THIS_MODULE;
68	strscpy(sd->name, name, sizeof(sd->name));
69	v4l2_set_subdevdata(sd, ved);
70
71	/* Expose this subdev to user space */
72	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
73	if (sd->ctrl_handler)
74		sd->flags |= V4L2_SUBDEV_FL_HAS_EVENTS;
75
76	/* Initialize the media entity */
77	ret = media_entity_pads_init(&sd->entity, num_pads, ved->pads);
78	if (ret)
79		goto err_clean_pads;
80
81	ret = v4l2_subdev_init_finalize(sd);
82	if (ret < 0)
83		goto err_clean_m_ent;
84
85	/* Register the subdev with the v4l2 and the media framework */
86	ret = v4l2_device_register_subdev(v4l2_dev, sd);
87	if (ret) {
88		dev_err(v4l2_dev->dev,
89			"%s: subdev register failed (err=%d)\n",
90			name, ret);
91		goto err_clean_m_ent;
92	}
93
94	ved->handler = handler;
95	ved->thread_fn = thread_fn;
96
97	return 0;
98
99err_clean_m_ent:
100	media_entity_cleanup(&sd->entity);
101err_clean_pads:
102	dcmipp_pads_cleanup(ved->pads);
103	return ret;
104}
105
106void
107dcmipp_ent_sd_unregister(struct dcmipp_ent_device *ved, struct v4l2_subdev *sd)
108{
109	media_entity_cleanup(ved->ent);
110	v4l2_device_unregister_subdev(sd);
111}
112