drivers/media/radio/tef6862.c

   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, struct v4l2_tuner *v)
 100 {
 101         return v->index ? -EINVAL : 0;
 102 }
 103
 104 static int tef6862_s_frequency(struct v4l2_subdev *sd, 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");