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[] = {I2C_CLIENT_END};
  38 static unsigned short normal_i2c_range[] = {0x60, 0x61, I2C_CLIENT_END};
  39 static unsigned short probe[2]        = { I2C_CLIENT_END, I2C_CLIENT_END };
  40 static unsigned short probe_range[2]  = { I2C_CLIENT_END, I2C_CLIENT_END };
  41 static unsigned short ignore[2]       = { I2C_CLIENT_END, I2C_CLIENT_END };
  42 static unsigned short ignore_range[2] = { I2C_CLIENT_END, I2C_CLIENT_END };
  43 static unsigned short force[2]        = { I2C_CLIENT_END, I2C_CLIENT_END };
  44
  45 static struct i2c_client_address_data addr_data = {
  46         normal_i2c, normal_i2c_range,
  47         probe, probe_range,
  48         ignore, ignore_range,
  49         force
  50 };
  51
  52 /* ---------------------------------------------------------------------- */
  53
  54 static unsigned char
  55 tuner_getstatus (struct i2c_client *c)
  56 {
  57         unsigned char byte;
  58         if (i2c_master_recv(c, &byte, 1) != 1)
  59                 printk(KERN_ERR "tuner-3036: I/O error.\n");
  60         return byte;
  61 }
  62
  63 #define TUNER_FL        0x80
  64
  65 static int
  66 tuner_islocked (struct i2c_client *c)
  67 {
  68         return (tuner_getstatus(c) & TUNER_FL);
  69 }
  70
  71 /* ---------------------------------------------------------------------- */
  72
  73 static void
  74 set_tv_freq(struct i2c_client *c, int freq)
  75 {
  76         u16 div = ((freq * 20) / 16);
  77         unsigned long give_up = jiffies + HZ;
  78         unsigned char buffer[2];
  79
  80         if (debug)
  81                 printk(KERN_DEBUG "tuner: setting frequency %dMHz, divisor %x\n", freq / 16, div);
  82
  83         /* Select high tuning current */
  84         buffer[0] = 0x29;
  85         buffer[1] = 0x3e;
  86
  87         if (i2c_master_send(c, buffer, 2) != 2)
  88                 printk("tuner: i2c i/o error 1\n");
  89
  90         buffer[0] = 0x80 | ((div>>8) & 0x7f);
  91         buffer[1] = div & 0xff;
  92
  93         if (i2c_master_send(c, buffer, 2) != 2)
  94                 printk("tuner: i2c i/o error 2\n");
  95
  96         while (!tuner_islocked(c) && time_before(jiffies, give_up))
  97                 schedule();
  98
  99         if (!tuner_islocked(c))
 100                 printk(KERN_WARNING "tuner: failed to achieve PLL lock\n");
 101
 102         /* Select low tuning current and engage AFC */
 103         buffer[0] = 0x29;
 104         buffer[1] = 0xb2;
 105
 106         if (i2c_master_send(c, buffer, 2) != 2)
 107                 printk("tuner: i2c i/o error 3\n");
 108
 109         if (debug)
 110                 printk(KERN_DEBUG "tuner: status %02x\n", tuner_getstatus(c));
 111 }
 112
 113 /* ---------------------------------------------------------------------- */
 114
 115 static int
 116 tuner_attach(struct i2c_adapter *adap, int addr, int kind)
 117 {
 118         static unsigned char buffer[] = { 0x29, 0x32, 0x2a, 0, 0x2b, 0 };
 119
 120         struct i2c_client *client;
 121
 122         if (this_adap > 0)
 123                 return -1;
 124         this_adap++;
 125
 126         client_template.adapter = adap;
 127         client_template.addr = addr;
 128
 129         client = kmalloc(sizeof(struct i2c_client), GFP_KERNEL);
 130         if (client == NULL)
 131                 return -ENOMEM;
 132         memcpy(client, &client_template, sizeof(struct i2c_client));
 133
 134         printk("tuner: SAB3036 found, status %02x\n", tuner_getstatus(client));
 135
 136         i2c_attach_client(client);
 137
 138         if (i2c_master_send(client, buffer, 2) != 2)
 139                 printk("tuner: i2c i/o error 1\n");
 140         if (i2c_master_send(client, buffer+2, 2) != 2)
 141                 printk("tuner: i2c i/o error 2\n");
 142         if (i2c_master_send(client, buffer+4, 2) != 2)
 143                 printk("tuner: i2c i/o error 3\n");
 144         return 0;
 145 }
 146
 147 static int
 148 tuner_detach(struct i2c_client *c)
 149 {
 150         return 0;
 151 }
 152
 153 static int
 154 tuner_command(struct i2c_client *client, unsigned int cmd, void *arg)
 155 {
 156         int *iarg = (int*)arg;
 157
 158         switch (cmd)
 159         {
 160                 case TUNER_SET_TVFREQ:
 161                         set_tv_freq(client, *iarg);
 162                         break;
 163
 164                 default:
 165                         return -EINVAL;
 166         }
 167         return 0;
 168 }
 169
 170 static int
 171 tuner_probe(struct i2c_adapter *adap)
 172 {
 173         this_adap = 0;
 174         if (adap->id == (I2C_ALGO_BIT | I2C_HW_B_LP))
 175                 return i2c_probe(adap, &addr_data, tuner_attach);
 176         return 0;
 177 }
 178
 179 /* ----------------------------------------------------------------------- */
 180
 181 static struct i2c_driver
 182 i2c_driver_tuner =
 183 {
 184         .owner          =       THIS_MODULE,
 185         .name           =       "sab3036",
 186         .id             =       I2C_DRIVERID_SAB3036,
 187         .flags          =       I2C_DF_NOTIFY,
 188         .attach_adapter =       tuner_probe,
 189         .detach_client  =       tuner_detach,
 190         .command        =       tuner_command
 191 };
 192
 193 static struct i2c_client client_template =
 194 {
 195         .driver         = &i2c_driver_tuner,
 196         .name           = "SAB3036",
 197 };
 198
 199 static int __init
 200 tuner3036_init(void)
 201 {
 202         i2c_add_driver(&i2c_driver_tuner);
 203         return 0;
 204 }
 205
 206 static void __exit
 207 tuner3036_exit(void)
 208 {
 209         i2c_del_driver(&i2c_driver_tuner);
 210 }
 211
 212 MODULE_DESCRIPTION("SAB3036 tuner driver");
 213 MODULE_AUTHOR("Philip Blundell <philb@gnu.org>");
 214 MODULE_LICENSE("GPL");
 215
 216 module_param(debug, int, 0);
 217 MODULE_PARM_DESC(debug,"Enable debugging output");
 218
 219 module_init(tuner3036_init);
 220 module_exit(tuner3036_exit);