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
32static int debug;	/* insmod parameter */
33static int this_adap;
34
35static struct i2c_client client_template;
36
37/* Addresses to scan */
38static unsigned short normal_i2c[] = { 0x60, 0x61, I2C_CLIENT_END };
39static unsigned short ignore = I2C_CLIENT_END;
40
41static struct i2c_client_address_data addr_data = {
42	.normal_i2c	= normal_i2c,
43	.probe		= &ignore,
44	.ignore		= &ignore,
45};
46
47/* ---------------------------------------------------------------------- */
48
49static unsigned char
50tuner_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
60static int
61tuner_islocked (struct i2c_client *c)
62{
63	return (tuner_getstatus(c) & TUNER_FL);
64}
65
66/* ---------------------------------------------------------------------- */
67
68static void
69set_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
110static int
111tuner_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
142static int
143tuner_detach(struct i2c_client *c)
144{
145	return 0;
146}
147
148static int
149tuner_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
165static int
166tuner_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
176static struct i2c_driver
177i2c_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
188static struct i2c_client client_template =
189{
190	.driver		= &i2c_driver_tuner,
191	.name		= "SAB3036",
192};
193
194static int __init
195tuner3036_init(void)
196{
197	return i2c_add_driver(&i2c_driver_tuner);
198}
199
200static void __exit
201tuner3036_exit(void)
202{
203	i2c_del_driver(&i2c_driver_tuner);
204}
205
206MODULE_DESCRIPTION("SAB3036 tuner driver");
207MODULE_AUTHOR("Philip Blundell <philb@gnu.org>");
208MODULE_LICENSE("GPL");
209
210module_param(debug, int, 0);
211MODULE_PARM_DESC(debug,"Enable debugging output");
212
213module_init(tuner3036_init);
214module_exit(tuner3036_exit);
215