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/init.h>
  25
  26 #include <linux/i2c.h>
  27 #include <linux/videodev.h>
  28
  29 #include <media/tuner.h>
  30
  31 static int debug;       /* insmod parameter */
  32 static int this_adap;
  33
  34 static struct i2c_client client_template;
  35
  36 /* Addresses to scan */
  37 static unsigned short normal_i2c[] = { 0x60, 0x61, I2C_CLIENT_END };
  38 static unsigned short probe[2]        = { I2C_CLIENT_END, I2C_CLIENT_END };
  39 static unsigned short ignore[2]       = { I2C_CLIENT_END, I2C_CLIENT_END };
  40 static unsigned short force[2]        = { I2C_CLIENT_END, I2C_CLIENT_END };
  41
  42 static struct i2c_client_address_data addr_data = {
  43         .normal_i2c     = normal_i2c,
  44         .probe          = probe,
  45         .ignore         = ignore,
  46         .force          = force,
  47 };
  48
  49 /* ---------------------------------------------------------------------- */
  50
  51 static unsigned char
  52 tuner_getstatus (struct i2c_client *c)
  53 {
  54         unsigned char byte;
  55         if (i2c_master_recv(c, &byte, 1) != 1)
  56                 printk(KERN_ERR "tuner-3036: I/O error.\n");
  57         return byte;
  58 }
  59
  60 #define TUNER_FL        0x80
  61
  62 static int
  63 tuner_islocked (struct i2c_client *c)
  64 {
  65         return (tuner_getstatus(c) & TUNER_FL);
  66 }
  67
  68 /* ---------------------------------------------------------------------- */
  69
  70 static void
  71 set_tv_freq(struct i2c_client *c, int freq)
  72 {
  73         u16 div = ((freq * 20) / 16);
  74         unsigned long give_up = jiffies + HZ;
  75         unsigned char buffer[2];
  76
  77         if (debug)
  78                 printk(KERN_DEBUG "tuner: setting frequency %dMHz, divisor %x\n", freq / 16, div);
  79
  80         /* Select high tuning current */
  81         buffer[0] = 0x29;
  82         buffer[1] = 0x3e;
  83
  84         if (i2c_master_send(c, buffer, 2) != 2)
  85                 printk("tuner: i2c i/o error 1\n");
  86
  87         buffer[0] = 0x80 | ((div>>8) & 0x7f);
  88         buffer[1] = div & 0xff;
  89
  90         if (i2c_master_send(c, buffer, 2) != 2)
  91                 printk("tuner: i2c i/o error 2\n");
  92
  93         while (!tuner_islocked(c) && time_before(jiffies, give_up))
  94                 schedule();
  95
  96         if (!tuner_islocked(c))
  97                 printk(KERN_WARNING "tuner: failed to achieve PLL lock\n");
  98
  99         /* Select low tuning current and engage AFC */
 100         buffer[0] = 0x29;
 101         buffer[1] = 0xb2;
 102
 103         if (i2c_master_send(c, buffer, 2) != 2)
 104                 printk("tuner: i2c i/o error 3\n");
 105
 106         if (debug)
 107                 printk(KERN_DEBUG "tuner: status %02x\n", tuner_getstatus(c));
 108 }
 109
 110 /* ---------------------------------------------------------------------- */
 111
 112 static int
 113 tuner_attach(struct i2c_adapter *adap, int addr, int kind)
 114 {
 115         static unsigned char buffer[] = { 0x29, 0x32, 0x2a, 0, 0x2b, 0 };
 116
 117         struct i2c_client *client;
 118
 119         if (this_adap > 0)
 120                 return -1;
 121         this_adap++;
 122
 123         client_template.adapter = adap;
 124         client_template.addr = addr;
 125
 126         client = kmalloc(sizeof(struct i2c_client), GFP_KERNEL);
 127         if (client == NULL)
 128                 return -ENOMEM;
 129         memcpy(client, &client_template, sizeof(struct i2c_client));
 130
 131         printk("tuner: SAB3036 found, status %02x\n", tuner_getstatus(client));
 132
 133         i2c_attach_client(client);
 134
 135         if (i2c_master_send(client, buffer, 2) != 2)
 136                 printk("tuner: i2c i/o error 1\n");
 137         if (i2c_master_send(client, buffer+2, 2) != 2)
 138                 printk("tuner: i2c i/o error 2\n");
 139         if (i2c_master_send(client, buffer+4, 2) != 2)
 140                 printk("tuner: i2c i/o error 3\n");
 141         return 0;
 142 }
 143
 144 static int
 145 tuner_detach(struct i2c_client *c)
 146 {
 147         return 0;
 148 }
 149
 150 static int
 151 tuner_command(struct i2c_client *client, unsigned int cmd, void *arg)
 152 {
 153         int *iarg = (int*)arg;
 154
 155         switch (cmd)
 156         {
 157                 case TUNER_SET_TVFREQ:
 158                         set_tv_freq(client, *iarg);
 159                         break;
 160
 161                 default:
 162                         return -EINVAL;
 163         }
 164         return 0;
 165 }
 166
 167 static int
 168 tuner_probe(struct i2c_adapter *adap)
 169 {
 170         this_adap = 0;
 171         if (adap->id == (I2C_ALGO_BIT | I2C_HW_B_LP))
 172                 return i2c_probe(adap, &addr_data, tuner_attach);
 173         return 0;
 174 }
 175
 176 /* ----------------------------------------------------------------------- */
 177
 178 static struct i2c_driver
 179 i2c_driver_tuner =
 180 {
 181         .owner          =       THIS_MODULE,
 182         .name           =       "sab3036",
 183         .id             =       I2C_DRIVERID_SAB3036,
 184         .flags          =       I2C_DF_NOTIFY,
 185         .attach_adapter =       tuner_probe,
 186         .detach_client  =       tuner_detach,
 187         .command        =       tuner_command
 188 };
 189
 190 static struct i2c_client client_template =
 191 {
 192         .driver         = &i2c_driver_tuner,
 193         .name           = "SAB3036",
 194 };
 195
 196 static int __init
 197 tuner3036_init(void)
 198 {
 199         i2c_add_driver(&i2c_driver_tuner);
 200         return 0;
 201 }
 202
 203 static void __exit
 204 tuner3036_exit(void)
 205 {
 206         i2c_del_driver(&i2c_driver_tuner);
 207 }
 208
 209 MODULE_DESCRIPTION("SAB3036 tuner driver");
 210 MODULE_AUTHOR("Philip Blundell <philb@gnu.org>");
 211 MODULE_LICENSE("GPL");
 212
 213 module_param(debug, int, 0);
 214 MODULE_PARM_DESC(debug,"Enable debugging output");
 215
 216 module_init(tuner3036_init);
 217 module_exit(tuner3036_exit);