1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * tef6862.c Philips TEF6862 Car Radio Enhanced Selectivity Tuner
4 * Copyright (c) 2009 Intel Corporation
5 */
6
7#include <linux/module.h>
8#include <linux/init.h>
9#include <linux/errno.h>
10#include <linux/kernel.h>
11#include <linux/interrupt.h>
12#include <linux/i2c.h>
13#include <linux/slab.h>
14#include <media/v4l2-ioctl.h>
15#include <media/v4l2-device.h>
16
17#define DRIVER_NAME "tef6862"
18
19#define FREQ_MUL 16000
20
21#define TEF6862_LO_FREQ (875U * FREQ_MUL / 10)
22#define TEF6862_HI_FREQ (108U * FREQ_MUL)
23
24/* Write mode sub addresses */
25#define WM_SUB_BANDWIDTH 0x0
26#define WM_SUB_PLLM 0x1
27#define WM_SUB_PLLL 0x2
28#define WM_SUB_DAA 0x3
29#define WM_SUB_AGC 0x4
30#define WM_SUB_BAND 0x5
31#define WM_SUB_CONTROL 0x6
32#define WM_SUB_LEVEL 0x7
33#define WM_SUB_IFCF 0x8
34#define WM_SUB_IFCAP 0x9
35#define WM_SUB_ACD 0xA
36#define WM_SUB_TEST 0xF
37
38/* Different modes of the MSA register */
39#define MSA_MODE_BUFFER 0x0
40#define MSA_MODE_PRESET 0x1
41#define MSA_MODE_SEARCH 0x2
42#define MSA_MODE_AF_UPDATE 0x3
43#define MSA_MODE_JUMP 0x4
44#define MSA_MODE_CHECK 0x5
45#define MSA_MODE_LOAD 0x6
46#define MSA_MODE_END 0x7
47#define MSA_MODE_SHIFT 5
48
49struct tef6862_state {
50 struct v4l2_subdev sd;
51 unsigned long freq;
52};
53
54static inline struct tef6862_state *to_state(struct v4l2_subdev *sd)
55{
56 return container_of(sd, struct tef6862_state, sd);
57}
58
59static u16 tef6862_sigstr(struct i2c_client *client)
60{
61 u8 buf[4];
62 int err = i2c_master_recv(client, buf, count: sizeof(buf));
63 if (err == sizeof(buf))
64 return buf[3] << 8;
65 return 0;
66}
67
68static int tef6862_g_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *v)
69{
70 if (v->index > 0)
71 return -EINVAL;
72
73 /* only support FM for now */
74 strscpy(v->name, "FM", sizeof(v->name));
75 v->type = V4L2_TUNER_RADIO;
76 v->rangelow = TEF6862_LO_FREQ;
77 v->rangehigh = TEF6862_HI_FREQ;
78 v->rxsubchans = V4L2_TUNER_SUB_MONO;
79 v->capability = V4L2_TUNER_CAP_LOW;
80 v->audmode = V4L2_TUNER_MODE_STEREO;
81 v->signal = tef6862_sigstr(client: v4l2_get_subdevdata(sd));
82
83 return 0;
84}
85
86static int tef6862_s_tuner(struct v4l2_subdev *sd, const struct v4l2_tuner *v)
87{
88 return v->index ? -EINVAL : 0;
89}
90
91static int tef6862_s_frequency(struct v4l2_subdev *sd, const struct v4l2_frequency *f)
92{
93 struct tef6862_state *state = to_state(sd);
94 struct i2c_client *client = v4l2_get_subdevdata(sd);
95 unsigned freq = f->frequency;
96 u16 pll;
97 u8 i2cmsg[3];
98 int err;
99
100 if (f->tuner != 0)
101 return -EINVAL;
102
103 freq = clamp(freq, TEF6862_LO_FREQ, TEF6862_HI_FREQ);
104 pll = 1964 + ((freq - TEF6862_LO_FREQ) * 20) / FREQ_MUL;
105 i2cmsg[0] = (MSA_MODE_PRESET << MSA_MODE_SHIFT) | WM_SUB_PLLM;
106 i2cmsg[1] = (pll >> 8) & 0xff;
107 i2cmsg[2] = pll & 0xff;
108
109 err = i2c_master_send(client, buf: i2cmsg, count: sizeof(i2cmsg));
110 if (err != sizeof(i2cmsg))
111 return err < 0 ? err : -EIO;
112
113 state->freq = freq;
114 return 0;
115}
116
117static int tef6862_g_frequency(struct v4l2_subdev *sd, struct v4l2_frequency *f)
118{
119 struct tef6862_state *state = to_state(sd);
120
121 if (f->tuner != 0)
122 return -EINVAL;
123 f->type = V4L2_TUNER_RADIO;
124 f->frequency = state->freq;
125 return 0;
126}
127
128static const struct v4l2_subdev_tuner_ops tef6862_tuner_ops = {
129 .g_tuner = tef6862_g_tuner,
130 .s_tuner = tef6862_s_tuner,
131 .s_frequency = tef6862_s_frequency,
132 .g_frequency = tef6862_g_frequency,
133};
134
135static const struct v4l2_subdev_ops tef6862_ops = {
136 .tuner = &tef6862_tuner_ops,
137};
138
139/*
140 * Generic i2c probe
141 * concerning the addresses: i2c wants 7 bit (without the r/w bit), so '>>1'
142 */
143
144static int tef6862_probe(struct i2c_client *client)
145{
146 struct tef6862_state *state;
147 struct v4l2_subdev *sd;
148
149 /* Check if the adapter supports the needed features */
150 if (!i2c_check_functionality(adap: client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
151 return -EIO;
152
153 v4l_info(client, "chip found @ 0x%02x (%s)\n",
154 client->addr << 1, client->adapter->name);
155
156 state = kzalloc(size: sizeof(struct tef6862_state), GFP_KERNEL);
157 if (state == NULL)
158 return -ENOMEM;
159 state->freq = TEF6862_LO_FREQ;
160
161 sd = &state->sd;
162 v4l2_i2c_subdev_init(sd, client, ops: &tef6862_ops);
163
164 return 0;
165}
166
167static void tef6862_remove(struct i2c_client *client)
168{
169 struct v4l2_subdev *sd = i2c_get_clientdata(client);
170
171 v4l2_device_unregister_subdev(sd);
172 kfree(objp: to_state(sd));
173}
174
175static const struct i2c_device_id tef6862_id[] = {
176 {DRIVER_NAME, 0},
177 {},
178};
179
180MODULE_DEVICE_TABLE(i2c, tef6862_id);
181
182static struct i2c_driver tef6862_driver = {
183 .driver = {
184 .name = DRIVER_NAME,
185 },
186 .probe = tef6862_probe,
187 .remove = tef6862_remove,
188 .id_table = tef6862_id,
189};
190
191module_i2c_driver(tef6862_driver);
192
193MODULE_DESCRIPTION("TEF6862 Car Radio Enhanced Selectivity Tuner");
194MODULE_AUTHOR("Mocean Laboratories");
195MODULE_LICENSE("GPL v2");
196

source code of linux/drivers/media/radio/tef6862.c