1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * drivers/media/radio/radio-si4713.c
4 *
5 * Platform Driver for Silicon Labs Si4713 FM Radio Transmitter:
6 *
7 * Copyright (c) 2008 Instituto Nokia de Tecnologia - INdT
8 * Contact: Eduardo Valentin <eduardo.valentin@nokia.com>
9 */
10
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/platform_device.h>
15#include <linux/i2c.h>
16#include <linux/videodev2.h>
17#include <linux/slab.h>
18#include <media/v4l2-device.h>
19#include <media/v4l2-common.h>
20#include <media/v4l2-ioctl.h>
21#include <media/v4l2-fh.h>
22#include <media/v4l2-ctrls.h>
23#include <media/v4l2-event.h>
24#include "si4713.h"
25
26/* module parameters */
27static int radio_nr = -1; /* radio device minor (-1 ==> auto assign) */
28module_param(radio_nr, int, 0);
29MODULE_PARM_DESC(radio_nr,
30 "Minor number for radio device (-1 ==> auto assign)");
31
32MODULE_LICENSE("GPL v2");
33MODULE_AUTHOR("Eduardo Valentin <eduardo.valentin@nokia.com>");
34MODULE_DESCRIPTION("Platform driver for Si4713 FM Radio Transmitter");
35MODULE_VERSION("0.0.1");
36MODULE_ALIAS("platform:radio-si4713");
37
38/* Driver state struct */
39struct radio_si4713_device {
40 struct v4l2_device v4l2_dev;
41 struct video_device radio_dev;
42 struct mutex lock;
43};
44
45/* radio_si4713_fops - file operations interface */
46static const struct v4l2_file_operations radio_si4713_fops = {
47 .owner = THIS_MODULE,
48 .open = v4l2_fh_open,
49 .release = v4l2_fh_release,
50 .poll = v4l2_ctrl_poll,
51 /* Note: locking is done at the subdev level in the i2c driver. */
52 .unlocked_ioctl = video_ioctl2,
53};
54
55/* Video4Linux Interface */
56
57/* radio_si4713_querycap - query device capabilities */
58static int radio_si4713_querycap(struct file *file, void *priv,
59 struct v4l2_capability *capability)
60{
61 strscpy(capability->driver, "radio-si4713", sizeof(capability->driver));
62 strscpy(capability->card, "Silicon Labs Si4713 Modulator",
63 sizeof(capability->card));
64 strscpy(capability->bus_info, "platform:radio-si4713",
65 sizeof(capability->bus_info));
66 return 0;
67}
68
69/*
70 * v4l2 ioctl call backs.
71 * we are just a wrapper for v4l2_sub_devs.
72 */
73static inline struct v4l2_device *get_v4l2_dev(struct file *file)
74{
75 return &((struct radio_si4713_device *)video_drvdata(file))->v4l2_dev;
76}
77
78static int radio_si4713_g_modulator(struct file *file, void *p,
79 struct v4l2_modulator *vm)
80{
81 return v4l2_device_call_until_err(get_v4l2_dev(file), 0, tuner,
82 g_modulator, vm);
83}
84
85static int radio_si4713_s_modulator(struct file *file, void *p,
86 const struct v4l2_modulator *vm)
87{
88 return v4l2_device_call_until_err(get_v4l2_dev(file), 0, tuner,
89 s_modulator, vm);
90}
91
92static int radio_si4713_g_frequency(struct file *file, void *p,
93 struct v4l2_frequency *vf)
94{
95 return v4l2_device_call_until_err(get_v4l2_dev(file), 0, tuner,
96 g_frequency, vf);
97}
98
99static int radio_si4713_s_frequency(struct file *file, void *p,
100 const struct v4l2_frequency *vf)
101{
102 return v4l2_device_call_until_err(get_v4l2_dev(file), 0, tuner,
103 s_frequency, vf);
104}
105
106static long radio_si4713_default(struct file *file, void *p,
107 bool valid_prio, unsigned int cmd, void *arg)
108{
109 return v4l2_device_call_until_err(get_v4l2_dev(file), 0, core,
110 ioctl, cmd, arg);
111}
112
113static const struct v4l2_ioctl_ops radio_si4713_ioctl_ops = {
114 .vidioc_querycap = radio_si4713_querycap,
115 .vidioc_g_modulator = radio_si4713_g_modulator,
116 .vidioc_s_modulator = radio_si4713_s_modulator,
117 .vidioc_g_frequency = radio_si4713_g_frequency,
118 .vidioc_s_frequency = radio_si4713_s_frequency,
119 .vidioc_log_status = v4l2_ctrl_log_status,
120 .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
121 .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
122 .vidioc_default = radio_si4713_default,
123};
124
125/* radio_si4713_vdev_template - video device interface */
126static const struct video_device radio_si4713_vdev_template = {
127 .fops = &radio_si4713_fops,
128 .name = "radio-si4713",
129 .release = video_device_release_empty,
130 .ioctl_ops = &radio_si4713_ioctl_ops,
131 .vfl_dir = VFL_DIR_TX,
132};
133
134/* Platform driver interface */
135/* radio_si4713_pdriver_probe - probe for the device */
136static int radio_si4713_pdriver_probe(struct platform_device *pdev)
137{
138 struct radio_si4713_platform_data *pdata = pdev->dev.platform_data;
139 struct radio_si4713_device *rsdev;
140 struct v4l2_subdev *sd;
141 int rval = 0;
142
143 if (!pdata) {
144 dev_err(&pdev->dev, "Cannot proceed without platform data.\n");
145 rval = -EINVAL;
146 goto exit;
147 }
148
149 rsdev = devm_kzalloc(dev: &pdev->dev, size: sizeof(*rsdev), GFP_KERNEL);
150 if (!rsdev) {
151 dev_err(&pdev->dev, "Failed to alloc video device.\n");
152 rval = -ENOMEM;
153 goto exit;
154 }
155 mutex_init(&rsdev->lock);
156
157 rval = v4l2_device_register(dev: &pdev->dev, v4l2_dev: &rsdev->v4l2_dev);
158 if (rval) {
159 dev_err(&pdev->dev, "Failed to register v4l2 device.\n");
160 goto exit;
161 }
162
163 sd = i2c_get_clientdata(client: pdata->subdev);
164 rval = v4l2_device_register_subdev(v4l2_dev: &rsdev->v4l2_dev, sd);
165 if (rval) {
166 dev_err(&pdev->dev, "Cannot get v4l2 subdevice\n");
167 goto unregister_v4l2_dev;
168 }
169
170 rsdev->radio_dev = radio_si4713_vdev_template;
171 rsdev->radio_dev.v4l2_dev = &rsdev->v4l2_dev;
172 rsdev->radio_dev.ctrl_handler = sd->ctrl_handler;
173 /* Serialize all access to the si4713 */
174 rsdev->radio_dev.lock = &rsdev->lock;
175 rsdev->radio_dev.device_caps = V4L2_CAP_MODULATOR | V4L2_CAP_RDS_OUTPUT;
176 video_set_drvdata(vdev: &rsdev->radio_dev, data: rsdev);
177 if (video_register_device(vdev: &rsdev->radio_dev, type: VFL_TYPE_RADIO, nr: radio_nr)) {
178 dev_err(&pdev->dev, "Could not register video device.\n");
179 rval = -EIO;
180 goto unregister_v4l2_dev;
181 }
182 dev_info(&pdev->dev, "New device successfully probed\n");
183
184 goto exit;
185
186unregister_v4l2_dev:
187 v4l2_device_unregister(v4l2_dev: &rsdev->v4l2_dev);
188exit:
189 return rval;
190}
191
192/* radio_si4713_pdriver_remove - remove the device */
193static void radio_si4713_pdriver_remove(struct platform_device *pdev)
194{
195 struct v4l2_device *v4l2_dev = platform_get_drvdata(pdev);
196 struct radio_si4713_device *rsdev;
197
198 rsdev = container_of(v4l2_dev, struct radio_si4713_device, v4l2_dev);
199 video_unregister_device(vdev: &rsdev->radio_dev);
200 v4l2_device_unregister(v4l2_dev: &rsdev->v4l2_dev);
201}
202
203static struct platform_driver radio_si4713_pdriver = {
204 .driver = {
205 .name = "radio-si4713",
206 },
207 .probe = radio_si4713_pdriver_probe,
208 .remove_new = radio_si4713_pdriver_remove,
209};
210
211module_platform_driver(radio_si4713_pdriver);
212

source code of linux/drivers/media/radio/si4713/radio-platform-si4713.c