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 #include <media/v4l2-common.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[] = { 0x60, 0x61, I2C_CLIENT_END };
  39 static unsigned short ignore = I2C_CLIENT_END;
  40
  41 static struct i2c_client_address_data addr_data = {
  42         .normal_i2c     = normal_i2c,
  43         .probe          = &ignore,
  44         .ignore         = &ignore,
  45 };
  46
  47 /* ---------------------------------------------------------------------- */
  48
  49 static unsigned char
  50 tuner_getstatus (struct i2c_client *c)
  51 {
  52         unsigned char byte;
  53         if (i2c_master_recv(c, &byte, 1) != 1)
  54                 printk(KERN_ERR "tuner-3036: I/O error.\n");
  55         return byte;
  56 }
  57
  58 #define TUNER_FL        0x80
  59
  60 static int
  61 tuner_islocked (struct i2c_client *c)
  62 {
  63         return (tuner_getstatus(c) & TUNER_FL);
  64 }
  65
  66 /* ---------------------------------------------------------------------- */
  67
  68 static void
  69 set_tv_freq(struct i2c_client *c, int freq)
  70 {
  71         u16 div = ((freq * 20) / 16);
  72         unsigned long give_up = jiffies + HZ;
  73         unsigned char buffer[2];
  74
  75         if (debug)
  76                 printk(KERN_DEBUG "tuner: setting frequency %dMHz, divisor %x\n", freq / 16, div);
  77
  78         /* Select high tuning current */
  79         buffer[0] = 0x29;
  80         buffer[1] = 0x3e;
  81
  82         if (i2c_master_send(c, buffer, 2) != 2)
  83                 printk("tuner: i2c i/o error 1\n");
  84
  85         buffer[0] = 0x80 | ((div>>8) & 0x7f);
  86         buffer[1] = div & 0xff;
  87
  88         if (i2c_master_send(c, buffer, 2) != 2)
  89                 printk("tuner: i2c i/o error 2\n");
  90
  91         while (!tuner_islocked(c) && time_before(jiffies, give_up))
  92                 schedule();
  93
  94         if (!tuner_islocked(c))
  95                 printk(KERN_WARNING "tuner: failed to achieve PLL lock\n");
  96
  97         /* Select low tuning current and engage AFC */
  98         buffer[0] = 0x29;
  99         buffer[1] = 0xb2;
 100
 101         if (i2c_master_send(c, buffer, 2) != 2)
 102                 printk("tuner: i2c i/o error 3\n");
 103
 104         if (debug)
 105                 printk(KERN_DEBUG "tuner: status %02x\n", tuner_getstatus(c));
 106 }
 107
 108 /* ---------------------------------------------------------------------- */
 109
 110 static int
 111 tuner_attach(struct i2c_adapter *adap, int addr, int kind)
 112 {
 113         static unsigned char buffer[] = { 0x29, 0x32, 0x2a, 0, 0x2b, 0 };
 114
 115         struct i2c_client *client;
 116
 117         if (this_adap > 0)
 118                 return -1;
 119         this_adap++;
 120
 121         client_template.adapter = adap;
 122         client_template.addr = addr;
 123
 124         client = kmalloc(sizeof(struct i2c_client), GFP_KERNEL);
 125         if (client == NULL)
 126                 return -ENOMEM;
 127         memcpy(client, &client_template, sizeof(struct i2c_client));
 128
 129         printk("tuner: SAB3036 found, status %02x\n", tuner_getstatus(client));
 130
 131         i2c_attach_client(client);
 132
 133         if (i2c_master_send(client, buffer, 2) != 2)
 134                 printk("tuner: i2c i/o error 1\n");
 135         if (i2c_master_send(client, buffer+2, 2) != 2)
 136                 printk("tuner: i2c i/o error 2\n");
 137         if (i2c_master_send(client, buffer+4, 2) != 2)
 138                 printk("tuner: i2c i/o error 3\n");
 139         return 0;
 140 }
 141
 142 static int
 143 tuner_detach(struct i2c_client *c)
 144 {
 145         return 0;
 146 }
 147
 148 static int
 149 tuner_command(struct i2c_client *client, unsigned int cmd, void *arg)
 150 {
 151         int *iarg = (int*)arg;
 152
 153         switch (cmd)
 154         {
 155                 case VIDIOCSFREQ:
 156                         set_tv_freq(client, *iarg);
 157                         break;
 158
 159                 default:
 160                         return -EINVAL;
 161         }
 162         return 0;
 163 }
 164
 165 static int
 166 tuner_probe(struct i2c_adapter *adap)
 167 {
 168         this_adap = 0;
 169         if (adap->id == I2C_HW_B_LP)
 170                 return i2c_probe(adap, &addr_data, tuner_attach);
 171         return 0;
 172 }
 173
 174 /* ----------------------------------------------------------------------- */
 175
 176 static struct i2c_driver
 177 i2c_driver_tuner =
 178 {
 179         .driver = {
 180                 .name   =       "sab3036",
 181         },
 182         .id             =       I2C_DRIVERID_SAB3036,
 183         .attach_adapter =       tuner_probe,
 184         .detach_client  =       tuner_detach,
 185         .command        =       tuner_command
 186 };
 187
 188 static struct i2c_client client_template =
 189 {
 190         .driver         = &i2c_driver_tuner,
 191         .name           = "SAB3036",
 192 };
 193
 194 static int __init
 195 tuner3036_init(void)
 196 {
 197         return i2c_add_driver(&i2c_driver_tuner);
 198 }
 199
 200 static void __exit
 201 tuner3036_exit(void)
 202 {
 203         i2c_del_driver(&i2c_driver_tuner);
 204 }
 205
 206 MODULE_DESCRIPTION("SAB3036 tuner driver");
 207 MODULE_AUTHOR("Philip Blundell <philb@gnu.org>");
 208 MODULE_LICENSE("GPL");
 209
 210 module_param(debug, int, 0);
 211 MODULE_PARM_DESC(debug,"Enable debugging output");
 212
 213 module_init(tuner3036_init);
 214 module_exit(tuner3036_exit);