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 "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
tuner_getstatus(struct i2c_client * c)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
tuner_islocked(struct i2c_client * c)67 tuner_islocked (struct i2c_client *c)
68 {
69 return (tuner_getstatus(c) & TUNER_FL);
70 }
71
72 /* ---------------------------------------------------------------------- */
73
74 static void
set_tv_freq(struct i2c_client * c,int freq)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
tuner_attach(struct i2c_adapter * adap,int addr,unsigned short flags,int kind)117 tuner_attach(struct i2c_adapter *adap, int addr,
118 unsigned short flags, int kind)
119 {
120 static unsigned char buffer[] = { 0x29, 0x32, 0x2a, 0, 0x2b, 0 };
121
122 struct i2c_client *client;
123
124 if (this_adap > 0)
125 return -1;
126 this_adap++;
127
128 client_template.adapter = adap;
129 client_template.addr = addr;
130
131 client = kmalloc(sizeof(struct i2c_client), GFP_KERNEL);
132 if (client == NULL)
133 return -ENOMEM;
134 memcpy(client, &client_template, sizeof(struct i2c_client));
135
136 printk("tuner: SAB3036 found, status %02x\n", tuner_getstatus(client));
137
138 i2c_attach_client(client);
139 MOD_INC_USE_COUNT;
140
141 if (i2c_master_send(client, buffer, 2) != 2)
142 printk("tuner: i2c i/o error 1\n");
143 if (i2c_master_send(client, buffer+2, 2) != 2)
144 printk("tuner: i2c i/o error 2\n");
145 if (i2c_master_send(client, buffer+4, 2) != 2)
146 printk("tuner: i2c i/o error 3\n");
147 return 0;
148 }
149
150 static int
tuner_detach(struct i2c_client * c)151 tuner_detach(struct i2c_client *c)
152 {
153 MOD_DEC_USE_COUNT;
154 return 0;
155 }
156
157 static int
tuner_command(struct i2c_client * client,unsigned int cmd,void * arg)158 tuner_command(struct i2c_client *client, unsigned int cmd, void *arg)
159 {
160 int *iarg = (int*)arg;
161
162 switch (cmd)
163 {
164 case TUNER_SET_TVFREQ:
165 set_tv_freq(client, *iarg);
166 break;
167
168 default:
169 return -EINVAL;
170 }
171 return 0;
172 }
173
174 static int
tuner_probe(struct i2c_adapter * adap)175 tuner_probe(struct i2c_adapter *adap)
176 {
177 this_adap = 0;
178 if (adap->id == (I2C_ALGO_BIT | I2C_HW_B_LP))
179 return i2c_probe(adap, &addr_data, tuner_attach);
180 return 0;
181 }
182
183 /* ----------------------------------------------------------------------- */
184
185 static struct i2c_driver
186 i2c_driver_tuner =
187 {
188 "sab3036", /* name */
189 I2C_DRIVERID_SAB3036, /* ID */
190 I2C_DF_NOTIFY,
191 tuner_probe,
192 tuner_detach,
193 tuner_command
194 };
195
196 static struct i2c_client client_template =
197 {
198 "SAB3036", /* name */
199 -1,
200 0,
201 0,
202 NULL,
203 &i2c_driver_tuner
204 };
205
206 EXPORT_NO_SYMBOLS;
207
208 int __init
tuner3036_init(void)209 tuner3036_init(void)
210 {
211 i2c_add_driver(&i2c_driver_tuner);
212 return 0;
213 }
214
215 void __exit
tuner3036_exit(void)216 tuner3036_exit(void)
217 {
218 i2c_del_driver(&i2c_driver_tuner);
219 }
220
221 MODULE_DESCRIPTION("SAB3036 tuner driver");
222 MODULE_AUTHOR("Philip Blundell <philb@gnu.org>");
223 MODULE_LICENSE("GPL");
224
225 MODULE_PARM(debug,"i");
226 MODULE_PARM_DESC(debug,"Enable debugging output");
227
228 module_init(tuner3036_init);
229 module_exit(tuner3036_exit);
230