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/*
* 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/version.h>
#include <linux/module.h>
#include <linux/slab.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 = NULL;
static int daca_attach_adapter(struct i2c_adapter *adapter);
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);
/* Unique ID allocation */
static int daca_id;
static int daca_initialized;
struct daca_data
{
int arf; /* place holder for furture use */
};
struct i2c_driver daca_driver = {
name: "DAC3550A driver V " DACA_VERSION,
id: I2C_DRIVERID_DACA,
flags: I2C_DF_NOTIFY,
attach_adapter: &daca_attach_adapter,
detach_client: &daca_detach_client,
command: NULL,
inc_use: NULL, /* &daca_inc_use, */
dec_use: NULL /* &daca_dev_use */
};
#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
*/
wait_ms(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...
*/
wait_ms(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)
{
int rc = 0;
struct i2c_client *new_client;
struct daca_data *data;
const char *client_name = "DAC 3550A Digital Equalizer";
new_client = kmalloc(
sizeof(struct i2c_client) + sizeof(struct daca_data),
GFP_KERNEL);
if (!new_client) {
rc = -ENOMEM;
goto bail;
}
/* This is tricky, but it will set the data to the right value. */
new_client->data = new_client + 1;
data = (struct daca_data *) (new_client->data);
new_client->addr = address;
new_client->data = data;
new_client->adapter = adapter;
new_client->driver = &daca_driver;
new_client->flags = 0;
strcpy(new_client->name,client_name);
new_client->id = daca_id++; /* Automatically unique */
if (daca_init_client(new_client)) {
rc = -ENODEV;
goto bail;
}
/* Tell the i2c layer a new client has arrived */
if (i2c_attach_client(new_client)) {
rc = -ENODEV;
goto bail;
}
bail:
if (rc && new_client)
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;
}
int
daca_cleanup(void)
{
if (!daca_initialized)
return -ENODEV;
i2c_del_driver(&daca_driver);
daca_initialized = 0;
return 0;
}
int
daca_init(void)
{
int rc;
if (daca_initialized)
return 0;
printk("dac3550a driver version %s (%s)\n",DACA_VERSION,DACA_DATE);
if ((rc = i2c_add_driver(&daca_driver))) {
printk("dac3550a: Driver registration failed, module not inserted.\n");
daca_cleanup();
return rc;
}
daca_initialized = 1;
return 0;
}
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