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
49 struct tef6862_state {
50 struct v4l2_subdev sd;
51 unsigned long freq;
52 };
53
to_state(struct v4l2_subdev * sd)54 static inline struct tef6862_state *to_state(struct v4l2_subdev *sd)
55 {
56 return container_of(sd, struct tef6862_state, sd);
57 }
58
tef6862_sigstr(struct i2c_client * client)59 static u16 tef6862_sigstr(struct i2c_client *client)
60 {
61 u8 buf[4];
62 int err = i2c_master_recv(client, buf, sizeof(buf));
63 if (err == sizeof(buf))
64 return buf[3] << 8;
65 return 0;
66 }
67
tef6862_g_tuner(struct v4l2_subdev * sd,struct v4l2_tuner * v)68 static 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(v4l2_get_subdevdata(sd));
82
83 return 0;
84 }
85
tef6862_s_tuner(struct v4l2_subdev * sd,const struct v4l2_tuner * v)86 static int tef6862_s_tuner(struct v4l2_subdev *sd, const struct v4l2_tuner *v)
87 {
88 return v->index ? -EINVAL : 0;
89 }
90
tef6862_s_frequency(struct v4l2_subdev * sd,const struct v4l2_frequency * f)91 static 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, i2cmsg, sizeof(i2cmsg));
110 if (err != sizeof(i2cmsg))
111 return err < 0 ? err : -EIO;
112
113 state->freq = freq;
114 return 0;
115 }
116
tef6862_g_frequency(struct v4l2_subdev * sd,struct v4l2_frequency * f)117 static 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
128 static 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
135 static 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
tef6862_probe(struct i2c_client * client)144 static 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(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(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, &tef6862_ops);
163
164 return 0;
165 }
166
tef6862_remove(struct i2c_client * client)167 static 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(to_state(sd));
173 }
174
175 static const struct i2c_device_id tef6862_id[] = {
176 { DRIVER_NAME },
177 {}
178 };
179
180 MODULE_DEVICE_TABLE(i2c, tef6862_id);
181
182 static 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
191 module_i2c_driver(tef6862_driver);
192
193 MODULE_DESCRIPTION("TEF6862 Car Radio Enhanced Selectivity Tuner");
194 MODULE_AUTHOR("Mocean Laboratories");
195 MODULE_LICENSE("GPL v2");
196