drivers/media/video/tuner-3036.c

   1 /*
   2  * Driver for Philips SAB3036 "CITAC" tuner control chip.
   3  *
   4  * Author: Phil Blundell <philb@gnu.org>
   5  *
   6  * The SAB3036 is just about different enough from the chips that
   7  * tuner.c copes with to make it not worth the effort to crowbar
   8  * the support into that file.  So instead we have a separate driver.
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License
  12  * as published by the Free Software Foundation; either version
  13  * 2 of the License, or (at your option) any later version.
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/kernel.h>
  18 #include <linux/sched.h>
  19 #include <linux/string.h>
  20 #include <linux/timer.h>
  21 #include <linux/delay.h>
  22 #include <linux/errno.h>
  23 #include <linux/slab.h>
  24 #include <linux/version.h>
  25 #include <linux/init.h>
  26
  27 #include <linux/i2c.h>
  28 #include <linux/videodev.h>
  29
  30 #include <media/tuner.h>
  31
  32 static int debug;       /* insmod parameter */
  33 static int this_adap;
  34
  35 static struct i2c_client client_template;
  36
  37 /* Addresses to scan */
  38 static unsigned short normal_i2c[] = {I2C_CLIENT_END};
  39 static unsigned short normal_i2c_range[] = {0x60, 0x61, I2C_CLIENT_END};
  40 static unsigned short probe[2]        = { I2C_CLIENT_END, I2C_CLIENT_END };
  41 static unsigned short probe_range[2]  = { I2C_CLIENT_END, I2C_CLIENT_END };
  42 static unsigned short ignore[2]       = { I2C_CLIENT_END, I2C_CLIENT_END };
  43 static unsigned short ignore_range[2] = { I2C_CLIENT_END, I2C_CLIENT_END };
  44 static unsigned short force[2]        = { I2C_CLIENT_END, I2C_CLIENT_END };
  45
  46 static struct i2c_client_address_data addr_data = {
  47         normal_i2c, normal_i2c_range,
  48         probe, probe_range,
  49         ignore, ignore_range,
  50         force
  51 };
  52
  53 /* ---------------------------------------------------------------------- */
  54
  55 static unsigned char
  56 tuner_getstatus (struct i2c_client *c)
  57 {
  58         unsigned char byte;
  59         if (i2c_master_recv(c, &byte, 1) != 1)
  60                 printk(KERN_ERR "tuner-3036: I/O error.\n");
  61         return byte;
  62 }
  63
  64 #define TUNER_FL        0x80
  65
  66 static int
  67 tuner_islocked (struct i2c_client *c)
  68 {
  69         return (tuner_getstatus(c) & TUNER_FL);
  70 }
  71
  72 /* ---------------------------------------------------------------------- */
  73
  74 static void
  75 set_tv_freq(struct i2c_client *c, int freq)
  76 {
  77         u16 div = ((freq * 20) / 16);
  78         unsigned long give_up = jiffies + HZ;
  79         unsigned char buffer[2];
  80
  81         if (debug)
  82                 printk(KERN_DEBUG "tuner: setting frequency %dMHz, divisor %x\n", freq / 16, div);
  83
  84         /* Select high tuning current */
  85         buffer[0] = 0x29;
  86         buffer[1] = 0x3e;
  87
  88         if (i2c_master_send(c, buffer, 2) != 2)
  89                 printk("tuner: i2c i/o error 1\n");
  90
  91         buffer[0] = 0x80 | ((div>>8) & 0x7f);
  92         buffer[1] = div & 0xff;
  93
  94         if (i2c_master_send(c, buffer, 2) != 2)
  95                 printk("tuner: i2c i/o error 2\n");
  96
  97         while (!tuner_islocked(c) && time_before(jiffies, give_up))
  98                 schedule();
  99
 100         if (!tuner_islocked(c))
 101                 printk(KERN_WARNING "tuner: failed to achieve PLL lock\n");
 102
 103         /* Select low tuning current and engage AFC */
 104         buffer[0] = 0x29;
 105         buffer[1] = 0xb2;
 106
 107         if (i2c_master_send(c, buffer, 2) != 2)
 108                 printk("tuner: i2c i/o error 3\n");
 109
 110         if (debug)
 111                 printk(KERN_DEBUG "tuner: status %02x\n", tuner_getstatus(c));
 112 }
 113
 114 /* ---------------------------------------------------------------------- */
 115
 116 static int
 117 tuner_attach(struct i2c_adapter *adap, int addr, int kind)
 118 {
 119         static unsigned char buffer[] = { 0x29, 0x32, 0x2a, 0, 0x2b, 0 };
 120
 121         struct i2c_client *client;
 122
 123         if (this_adap > 0)
 124                 return -1;
 125         this_adap++;
 126
 127         client_template.adapter = adap;
 128         client_template.addr = addr;
 129
 130         client = kmalloc(sizeof(struct i2c_client), GFP_KERNEL);
 131         if (client == NULL)
 132                 return -ENOMEM;
 133         memcpy(client, &client_template, sizeof(struct i2c_client));
 134
 135         printk("tuner: SAB3036 found, status %02x\n", tuner_getstatus(client));
 136
 137         i2c_attach_client(client);
 138         MOD_INC_USE_COUNT;
 139
 140         if (i2c_master_send(client, buffer, 2) != 2)
 141                 printk("tuner: i2c i/o error 1\n");
 142         if (i2c_master_send(client, buffer+2, 2) != 2)
 143                 printk("tuner: i2c i/o error 2\n");
 144         if (i2c_master_send(client, buffer+4, 2) != 2)
 145                 printk("tuner: i2c i/o error 3\n");
 146         return 0;
 147 }
 148
 149 static int
 150 tuner_detach(struct i2c_client *c)
 151 {
 152         MOD_DEC_USE_COUNT;
 153         return 0;
 154 }
 155
 156 static int
 157 tuner_command(struct i2c_client *client, unsigned int cmd, void *arg)
 158 {
 159         int *iarg = (int*)arg;
 160
 161         switch (cmd)
 162         {
 163                 case TUNER_SET_TVFREQ:
 164                         set_tv_freq(client, *iarg);
 165                         break;
 166
 167                 default:
 168                         return -EINVAL;
 169         }
 170         return 0;
 171 }
 172
 173 static int
 174 tuner_probe(struct i2c_adapter *adap)
 175 {
 176         this_adap = 0;
 177         if (adap->id == (I2C_ALGO_BIT | I2C_HW_B_LP))
 178                 return i2c_probe(adap, &addr_data, tuner_attach);
 179         return 0;
 180 }
 181
 182 /* ----------------------------------------------------------------------- */
 183
 184 static struct i2c_driver
 185 i2c_driver_tuner =
 186 {
 187         .owner          =       THIS_MODULE,
 188         .name           =       "sab3036",
 189         .id             =       I2C_DRIVERID_SAB3036,
 190         .flags          =       I2C_DF_NOTIFY,
 191         .attach_adapter =       tuner_probe,
 192         .detach_client  =       tuner_detach,
 193         .command        =       tuner_command
 194 };
 195
 196 static struct i2c_client client_template =
 197 {
 198         .id             = -1,
 199         .driver         = &i2c_driver_tuner,
 200         .dev            = {
 201                 .name   = "SAB3036",
 202         },
 203 };
 204
 205 int __init
 206 tuner3036_init(void)
 207 {
 208         i2c_add_driver(&i2c_driver_tuner);
 209         return 0;
 210 }
 211
 212 void __exit
 213 tuner3036_exit(void)
 214 {
 215         i2c_del_driver(&i2c_driver_tuner);
 216 }
 217
 218 MODULE_DESCRIPTION("SAB3036 tuner driver");
 219 MODULE_AUTHOR("Philip Blundell <philb@gnu.org>");
 220 MODULE_LICENSE("GPL");
 221
 222 MODULE_PARM(debug,"i");
 223 MODULE_PARM_DESC(debug,"Enable debugging output");
 224
 225 module_init(tuner3036_init);
 226 module_exit(tuner3036_exit);