V4L/DVB (10261): em28xx: fix kernel panic on audio shutdown
[linux-2.6] / drivers / media / video / vp27smpx.c
1 /*
2  * vp27smpx - driver version 0.0.1
3  *
4  * Copyright (C) 2007 Hans Verkuil <hverkuil@xs4all.nl>
5  *
6  * Based on a tvaudio patch from Takahiro Adachi <tadachi@tadachi-net.com>
7  * and Kazuhiko Kawakami <kazz-0@mail.goo.ne.jp>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  */
23
24 #include <linux/module.h>
25 #include <linux/types.h>
26 #include <linux/ioctl.h>
27 #include <asm/uaccess.h>
28 #include <linux/i2c.h>
29 #include <linux/i2c-id.h>
30 #include <linux/videodev2.h>
31 #include <media/v4l2-device.h>
32 #include <media/v4l2-chip-ident.h>
33 #include <media/v4l2-i2c-drv.h>
34
35 MODULE_DESCRIPTION("vp27smpx driver");
36 MODULE_AUTHOR("Hans Verkuil");
37 MODULE_LICENSE("GPL");
38
39
40 /* ----------------------------------------------------------------------- */
41
42 struct vp27smpx_state {
43         struct v4l2_subdev sd;
44         int radio;
45         u32 audmode;
46 };
47
48 static inline struct vp27smpx_state *to_state(struct v4l2_subdev *sd)
49 {
50         return container_of(sd, struct vp27smpx_state, sd);
51 }
52
53 static void vp27smpx_set_audmode(struct v4l2_subdev *sd, u32 audmode)
54 {
55         struct vp27smpx_state *state = to_state(sd);
56         struct i2c_client *client = v4l2_get_subdevdata(sd);
57         u8 data[3] = { 0x00, 0x00, 0x04 };
58
59         switch (audmode) {
60         case V4L2_TUNER_MODE_MONO:
61         case V4L2_TUNER_MODE_LANG1:
62                 break;
63         case V4L2_TUNER_MODE_STEREO:
64         case V4L2_TUNER_MODE_LANG1_LANG2:
65                 data[1] = 0x01;
66                 break;
67         case V4L2_TUNER_MODE_LANG2:
68                 data[1] = 0x02;
69                 break;
70         }
71
72         if (i2c_master_send(client, data, sizeof(data)) != sizeof(data))
73                 v4l2_err(sd, "I/O error setting audmode\n");
74         else
75                 state->audmode = audmode;
76 }
77
78 static int vp27smpx_s_radio(struct v4l2_subdev *sd)
79 {
80         struct vp27smpx_state *state = to_state(sd);
81
82         state->radio = 1;
83         return 0;
84 }
85
86 static int vp27smpx_s_std(struct v4l2_subdev *sd, v4l2_std_id norm)
87 {
88         struct vp27smpx_state *state = to_state(sd);
89
90         state->radio = 0;
91         return 0;
92 }
93
94 static int vp27smpx_s_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *vt)
95 {
96         struct vp27smpx_state *state = to_state(sd);
97
98         if (!state->radio)
99                 vp27smpx_set_audmode(sd, vt->audmode);
100         return 0;
101 }
102
103 static int vp27smpx_g_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *vt)
104 {
105         struct vp27smpx_state *state = to_state(sd);
106
107         if (state->radio)
108                 return 0;
109         vt->audmode = state->audmode;
110         vt->capability = V4L2_TUNER_CAP_STEREO |
111                 V4L2_TUNER_CAP_LANG1 | V4L2_TUNER_CAP_LANG2;
112         vt->rxsubchans = V4L2_TUNER_SUB_MONO;
113         return 0;
114 }
115
116 static int vp27smpx_g_chip_ident(struct v4l2_subdev *sd, struct v4l2_dbg_chip_ident *chip)
117 {
118         struct i2c_client *client = v4l2_get_subdevdata(sd);
119
120         return v4l2_chip_ident_i2c_client(client, chip, V4L2_IDENT_VP27SMPX, 0);
121 }
122
123 static int vp27smpx_log_status(struct v4l2_subdev *sd)
124 {
125         struct vp27smpx_state *state = to_state(sd);
126
127         v4l2_info(sd, "Audio Mode: %u%s\n", state->audmode,
128                         state->radio ? " (Radio)" : "");
129         return 0;
130 }
131
132 static int vp27smpx_command(struct i2c_client *client, unsigned cmd, void *arg)
133 {
134         return v4l2_subdev_command(i2c_get_clientdata(client), cmd, arg);
135 }
136
137 /* ----------------------------------------------------------------------- */
138
139 static const struct v4l2_subdev_core_ops vp27smpx_core_ops = {
140         .log_status = vp27smpx_log_status,
141         .g_chip_ident = vp27smpx_g_chip_ident,
142 };
143
144 static const struct v4l2_subdev_tuner_ops vp27smpx_tuner_ops = {
145         .s_radio = vp27smpx_s_radio,
146         .s_std = vp27smpx_s_std,
147         .s_tuner = vp27smpx_s_tuner,
148         .g_tuner = vp27smpx_g_tuner,
149 };
150
151 static const struct v4l2_subdev_ops vp27smpx_ops = {
152         .core = &vp27smpx_core_ops,
153         .tuner = &vp27smpx_tuner_ops,
154 };
155
156 /* ----------------------------------------------------------------------- */
157
158 /* i2c implementation */
159
160 /*
161  * Generic i2c probe
162  * concerning the addresses: i2c wants 7 bit (without the r/w bit), so '>>1'
163  */
164
165 static int vp27smpx_probe(struct i2c_client *client,
166                           const struct i2c_device_id *id)
167 {
168         struct vp27smpx_state *state;
169         struct v4l2_subdev *sd;
170
171         /* Check if the adapter supports the needed features */
172         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
173                 return -EIO;
174
175         v4l_info(client, "chip found @ 0x%x (%s)\n",
176                         client->addr << 1, client->adapter->name);
177
178         state = kzalloc(sizeof(struct vp27smpx_state), GFP_KERNEL);
179         if (state == NULL)
180                 return -ENOMEM;
181         sd = &state->sd;
182         v4l2_i2c_subdev_init(sd, client, &vp27smpx_ops);
183         state->audmode = V4L2_TUNER_MODE_STEREO;
184
185         /* initialize vp27smpx */
186         vp27smpx_set_audmode(sd, state->audmode);
187         return 0;
188 }
189
190 static int vp27smpx_remove(struct i2c_client *client)
191 {
192         struct v4l2_subdev *sd = i2c_get_clientdata(client);
193
194         v4l2_device_unregister_subdev(sd);
195         kfree(to_state(sd));
196         return 0;
197 }
198
199 /* ----------------------------------------------------------------------- */
200
201 static const struct i2c_device_id vp27smpx_id[] = {
202         { "vp27smpx", 0 },
203         { }
204 };
205 MODULE_DEVICE_TABLE(i2c, vp27smpx_id);
206
207 static struct v4l2_i2c_driver_data v4l2_i2c_data = {
208         .name = "vp27smpx",
209         .driverid = I2C_DRIVERID_VP27SMPX,
210         .command = vp27smpx_command,
211         .probe = vp27smpx_probe,
212         .remove = vp27smpx_remove,
213         .id_table = vp27smpx_id,
214 };