xref: /openbmc/linux/drivers/media/radio/tef6862.c (revision ee89bd6b)
1 /*
2  * tef6862.c Philips TEF6862 Car Radio Enhanced Selectivity Tuner
3  * Copyright (c) 2009 Intel Corporation
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17  */
18 
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <linux/errno.h>
22 #include <linux/kernel.h>
23 #include <linux/interrupt.h>
24 #include <linux/i2c.h>
25 #include <linux/slab.h>
26 #include <media/v4l2-ioctl.h>
27 #include <media/v4l2-device.h>
28 #include <media/v4l2-chip-ident.h>
29 
30 #define DRIVER_NAME "tef6862"
31 
32 #define FREQ_MUL 16000
33 
34 #define TEF6862_LO_FREQ (875 * FREQ_MUL / 10)
35 #define TEF6862_HI_FREQ (108 * FREQ_MUL)
36 
37 /* Write mode sub addresses */
38 #define WM_SUB_BANDWIDTH	0x0
39 #define WM_SUB_PLLM		0x1
40 #define WM_SUB_PLLL		0x2
41 #define WM_SUB_DAA		0x3
42 #define WM_SUB_AGC		0x4
43 #define WM_SUB_BAND		0x5
44 #define WM_SUB_CONTROL		0x6
45 #define WM_SUB_LEVEL		0x7
46 #define WM_SUB_IFCF		0x8
47 #define WM_SUB_IFCAP		0x9
48 #define WM_SUB_ACD		0xA
49 #define WM_SUB_TEST		0xF
50 
51 /* Different modes of the MSA register */
52 #define MODE_BUFFER		0x0
53 #define MODE_PRESET		0x1
54 #define MODE_SEARCH		0x2
55 #define MODE_AF_UPDATE		0x3
56 #define MODE_JUMP		0x4
57 #define MODE_CHECK		0x5
58 #define MODE_LOAD		0x6
59 #define MODE_END		0x7
60 #define MODE_SHIFT		5
61 
62 struct tef6862_state {
63 	struct v4l2_subdev sd;
64 	unsigned long freq;
65 };
66 
67 static inline struct tef6862_state *to_state(struct v4l2_subdev *sd)
68 {
69 	return container_of(sd, struct tef6862_state, sd);
70 }
71 
72 static u16 tef6862_sigstr(struct i2c_client *client)
73 {
74 	u8 buf[4];
75 	int err = i2c_master_recv(client, buf, sizeof(buf));
76 	if (err == sizeof(buf))
77 		return buf[3] << 8;
78 	return 0;
79 }
80 
81 static int tef6862_g_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *v)
82 {
83 	if (v->index > 0)
84 		return -EINVAL;
85 
86 	/* only support FM for now */
87 	strlcpy(v->name, "FM", sizeof(v->name));
88 	v->type = V4L2_TUNER_RADIO;
89 	v->rangelow = TEF6862_LO_FREQ;
90 	v->rangehigh = TEF6862_HI_FREQ;
91 	v->rxsubchans = V4L2_TUNER_SUB_MONO;
92 	v->capability = V4L2_TUNER_CAP_LOW;
93 	v->audmode = V4L2_TUNER_MODE_STEREO;
94 	v->signal = tef6862_sigstr(v4l2_get_subdevdata(sd));
95 
96 	return 0;
97 }
98 
99 static int tef6862_s_tuner(struct v4l2_subdev *sd, const struct v4l2_tuner *v)
100 {
101 	return v->index ? -EINVAL : 0;
102 }
103 
104 static int tef6862_s_frequency(struct v4l2_subdev *sd, const struct v4l2_frequency *f)
105 {
106 	struct tef6862_state *state = to_state(sd);
107 	struct i2c_client *client = v4l2_get_subdevdata(sd);
108 	u16 pll;
109 	u8 i2cmsg[3];
110 	int err;
111 
112 	if (f->tuner != 0)
113 		return -EINVAL;
114 
115 	pll = 1964 + ((f->frequency - TEF6862_LO_FREQ) * 20) / FREQ_MUL;
116 	i2cmsg[0] = (MODE_PRESET << MODE_SHIFT) | WM_SUB_PLLM;
117 	i2cmsg[1] = (pll >> 8) & 0xff;
118 	i2cmsg[2] = pll & 0xff;
119 
120 	err = i2c_master_send(client, i2cmsg, sizeof(i2cmsg));
121 	if (err != sizeof(i2cmsg))
122 		return err < 0 ? err : -EIO;
123 
124 	state->freq = f->frequency;
125 	return 0;
126 }
127 
128 static int tef6862_g_frequency(struct v4l2_subdev *sd, struct v4l2_frequency *f)
129 {
130 	struct tef6862_state *state = to_state(sd);
131 
132 	if (f->tuner != 0)
133 		return -EINVAL;
134 	f->type = V4L2_TUNER_RADIO;
135 	f->frequency = state->freq;
136 	return 0;
137 }
138 
139 static int tef6862_g_chip_ident(struct v4l2_subdev *sd,
140 	struct v4l2_dbg_chip_ident *chip)
141 {
142 	struct i2c_client *client = v4l2_get_subdevdata(sd);
143 
144 	return v4l2_chip_ident_i2c_client(client, chip, V4L2_IDENT_TEF6862, 0);
145 }
146 
147 static const struct v4l2_subdev_tuner_ops tef6862_tuner_ops = {
148 	.g_tuner = tef6862_g_tuner,
149 	.s_tuner = tef6862_s_tuner,
150 	.s_frequency = tef6862_s_frequency,
151 	.g_frequency = tef6862_g_frequency,
152 };
153 
154 static const struct v4l2_subdev_core_ops tef6862_core_ops = {
155 	.g_chip_ident = tef6862_g_chip_ident,
156 };
157 
158 static const struct v4l2_subdev_ops tef6862_ops = {
159 	.core = &tef6862_core_ops,
160 	.tuner = &tef6862_tuner_ops,
161 };
162 
163 /*
164  * Generic i2c probe
165  * concerning the addresses: i2c wants 7 bit (without the r/w bit), so '>>1'
166  */
167 
168 static int tef6862_probe(struct i2c_client *client,
169 			 const struct i2c_device_id *id)
170 {
171 	struct tef6862_state *state;
172 	struct v4l2_subdev *sd;
173 
174 	/* Check if the adapter supports the needed features */
175 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
176 		return -EIO;
177 
178 	v4l_info(client, "chip found @ 0x%02x (%s)\n",
179 			client->addr << 1, client->adapter->name);
180 
181 	state = kzalloc(sizeof(struct tef6862_state), GFP_KERNEL);
182 	if (state == NULL)
183 		return -ENOMEM;
184 	state->freq = TEF6862_LO_FREQ;
185 
186 	sd = &state->sd;
187 	v4l2_i2c_subdev_init(sd, client, &tef6862_ops);
188 
189 	return 0;
190 }
191 
192 static int tef6862_remove(struct i2c_client *client)
193 {
194 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
195 
196 	v4l2_device_unregister_subdev(sd);
197 	kfree(to_state(sd));
198 	return 0;
199 }
200 
201 static const struct i2c_device_id tef6862_id[] = {
202 	{DRIVER_NAME, 0},
203 	{},
204 };
205 
206 MODULE_DEVICE_TABLE(i2c, tef6862_id);
207 
208 static struct i2c_driver tef6862_driver = {
209 	.driver = {
210 		.owner	= THIS_MODULE,
211 		.name	= DRIVER_NAME,
212 	},
213 	.probe		= tef6862_probe,
214 	.remove		= tef6862_remove,
215 	.id_table	= tef6862_id,
216 };
217 
218 module_i2c_driver(tef6862_driver);
219 
220 MODULE_DESCRIPTION("TEF6862 Car Radio Enhanced Selectivity Tuner");
221 MODULE_AUTHOR("Mocean Laboratories");
222 MODULE_LICENSE("GPL v2");
223