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, 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(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, i2cmsg, 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(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
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(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