summaryrefslogtreecommitdiffstats
path: root/sound/oss/dmasound/dac3550a.c
blob: 835e0cfc3bf34017f736e25f5e20ac092d451e03 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
/*
 * Driver for the i2c/i2s based DAC3550a sound chip used
 * on some Apple iBooks. Also known as "DACA".
 *
 *  This file is subject to the terms and conditions of the GNU General Public
 *  License.  See the file COPYING in the main directory of this archive
 *  for more details.
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/proc_fs.h>
#include <linux/ioport.h>
#include <linux/sysctl.h>
#include <linux/types.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <asm/uaccess.h>
#include <asm/errno.h>
#include <asm/io.h>

#include "dmasound.h"

/* FYI: This code was derived from the tas3001c.c Texas/Tumbler mixer
 * control code, as well as info derived from the AppleDACAAudio driver
 * from Darwin CVS (main thing I derived being register numbers and 
 * values, as well as when to make the calls). */

#define I2C_DRIVERID_DACA (0xFDCB)

#define DACA_VERSION	"0.1"
#define DACA_DATE "20010930"

static int cur_left_vol;
static int cur_right_vol;
static struct i2c_client *daca_client;

static int daca_attach_adapter(struct i2c_adapter *adapter);
static int daca_detect_client(struct i2c_adapter *adapter, int address);
static int daca_detach_client(struct i2c_client *client);

struct i2c_driver daca_driver = {  
	.driver = {
		.owner		= THIS_MODULE,
		.name		= "DAC3550A driver  V " DACA_VERSION,
	},
	.id			= I2C_DRIVERID_DACA,
	.attach_adapter		= daca_attach_adapter,
	.detach_client		= daca_detach_client,
};

#define VOL_MAX ((1<<20) - 1)

void daca_get_volume(uint * left_vol, uint  *right_vol)
{
	*left_vol = cur_left_vol >> 5;
	*right_vol = cur_right_vol >> 5;
}

int daca_set_volume(uint left_vol, uint right_vol)
{
	unsigned short voldata;
  
	if (!daca_client)
		return -1;

	/* Derived from experience, not from any specific values */
	left_vol <<= 5;
	right_vol <<= 5;

	if (left_vol > VOL_MAX)
		left_vol = VOL_MAX;
	if (right_vol > VOL_MAX)
		right_vol = VOL_MAX;

	voldata = ((left_vol >> 14)  & 0x3f) << 8;
	voldata |= (right_vol >> 14)  & 0x3f;
  
	if (i2c_smbus_write_word_data(daca_client, 2, voldata) < 0) {
		printk("daca: failed to set volume \n");
		return -1; 
	}

	cur_left_vol = left_vol;
	cur_right_vol = right_vol;
  
	return 0;
}

int daca_leave_sleep(void)
{
	if (!daca_client)
		return -1;
  
	/* Do a short sleep, just to make sure I2C bus is awake and paying
	 * attention to us
	 */
	msleep(20);
	/* Write the sample rate reg the value it needs */
	i2c_smbus_write_byte_data(daca_client, 1, 8);
	daca_set_volume(cur_left_vol >> 5, cur_right_vol >> 5);
	/* Another short delay, just to make sure the other I2C bus writes
	 * have taken...
	 */
	msleep(20);
	/* Write the global config reg - invert right power amp,
	 * DAC on, use 5-volt mode */
	i2c_smbus_write_byte_data(daca_client, 3, 0x45);

	return 0;
}

int daca_enter_sleep(void)
{
	if (!daca_client)
		return -1;

	i2c_smbus_write_byte_data(daca_client, 1, 8);
	daca_set_volume(cur_left_vol >> 5, cur_right_vol >> 5);

	/* Write the global config reg - invert right power amp,
	 * DAC on, enter low-power mode, use 5-volt mode
	 */
	i2c_smbus_write_byte_data(daca_client, 3, 0x65);

	return 0;
}

static int daca_attach_adapter(struct i2c_adapter *adapter)
{
	if (!strncmp(adapter->name, "mac-io", 6))
		daca_detect_client(adapter, 0x4d);
	return 0;
}

static int daca_init_client(struct i2c_client * new_client)
{
	/* 
	 * Probe is not working with the current i2c-keywest
	 * driver. We try to use addr 0x4d on each adapters
	 * instead, by setting the format register.
	 * 
	 * FIXME: I'm sure that can be obtained from the
	 * device-tree. --BenH.
	 */
  
	/* Write the global config reg - invert right power amp,
	 * DAC on, use 5-volt mode
	 */
	if (i2c_smbus_write_byte_data(new_client, 3, 0x45))
		return -1;

	i2c_smbus_write_byte_data(new_client, 1, 8);
	daca_client = new_client;
	daca_set_volume(15000, 15000);

	return 0;
}

static int daca_detect_client(struct i2c_adapter *adapter, int address)
{
	const char *client_name = "DAC 3550A Digital Equalizer";
	struct i2c_client *new_client;
	int rc = -ENODEV;

	new_client = kmalloc(sizeof(*new_client), GFP_KERNEL);
	if (!new_client)
		return -ENOMEM;
	memset(new_client, 0, sizeof(*new_client));

	new_client->addr = address;
	new_client->adapter = adapter;
	new_client->driver = &daca_driver;
	new_client->flags = 0;
	strcpy(new_client->name, client_name);

	if (daca_init_client(new_client))
		goto bail;

	/* Tell the i2c layer a new client has arrived */
	if (i2c_attach_client(new_client))
		goto bail;

	return 0;
 bail:
	kfree(new_client);
	return rc;
}


static int daca_detach_client(struct i2c_client *client)
{
	if (client == daca_client)
		daca_client = NULL;

  	i2c_detach_client(client);
	kfree(client);
	return 0;
}

void daca_cleanup(void)
{
	i2c_del_driver(&daca_driver);
}

int daca_init(void)
{
	printk("dac3550a driver version %s (%s)\n",DACA_VERSION,DACA_DATE);
	return i2c_add_driver(&daca_driver);
}
OpenPOWER on IntegriCloud