sound/oss/dmasound/dac3550a.c

   1 /*
   2  * Driver for the i2c/i2s based DAC3550a sound chip used
   3  * on some Apple iBooks. Also known as "DACA".
   4  *
   5  *  This file is subject to the terms and conditions of the GNU General Public
   6  *  License.  See the file COPYING in the main directory of this archive
   7  *  for more details.
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/slab.h>
  12 #include <linux/delay.h>
  13 #include <linux/proc_fs.h>
  14 #include <linux/ioport.h>
  15 #include <linux/sysctl.h>
  16 #include <linux/types.h>
  17 #include <linux/i2c.h>
  18 #include <linux/init.h>
  19 #include <asm/uaccess.h>
  20 #include <asm/errno.h>
  21 #include <asm/io.h>
  22
  23 #include "dmasound.h"
  24
  25 /* FYI: This code was derived from the tas3001c.c Texas/Tumbler mixer
  26  * control code, as well as info derived from the AppleDACAAudio driver
  27  * from Darwin CVS (main thing I derived being register numbers and
  28  * values, as well as when to make the calls). */
  29
  30 #define I2C_DRIVERID_DACA (0xFDCB)
  31
  32 #define DACA_VERSION    "0.1"
  33 #define DACA_DATE "20010930"
  34
  35 static int cur_left_vol;
  36 static int cur_right_vol;
  37 static struct i2c_client *daca_client;
  38
  39 static int daca_attach_adapter(struct i2c_adapter *adapter);
  40 static int daca_detect_client(struct i2c_adapter *adapter, int address);
  41 static int daca_detach_client(struct i2c_client *client);
  42
  43 struct i2c_driver daca_driver = {
  44         .owner                  = THIS_MODULE,
  45         .name                   = "DAC3550A driver  V " DACA_VERSION,
  46         .id                     = I2C_DRIVERID_DACA,
  47         .flags                  = I2C_DF_NOTIFY,
  48         .attach_adapter         = daca_attach_adapter,
  49         .detach_client          = daca_detach_client,
  50 };
  51
  52 #define VOL_MAX ((1<<20) - 1)
  53
  54 void daca_get_volume(uint * left_vol, uint  *right_vol)
  55 {
  56         *left_vol = cur_left_vol >> 5;
  57         *right_vol = cur_right_vol >> 5;
  58 }
  59
  60 int daca_set_volume(uint left_vol, uint right_vol)
  61 {
  62         unsigned short voldata;
  63
  64         if (!daca_client)
  65                 return -1;
  66
  67         /* Derived from experience, not from any specific values */
  68         left_vol <<= 5;
  69         right_vol <<= 5;
  70
  71         if (left_vol > VOL_MAX)
  72                 left_vol = VOL_MAX;
  73         if (right_vol > VOL_MAX)
  74                 right_vol = VOL_MAX;
  75
  76         voldata = ((left_vol >> 14)  & 0x3f) << 8;
  77         voldata |= (right_vol >> 14)  & 0x3f;
  78
  79         if (i2c_smbus_write_word_data(daca_client, 2, voldata) < 0) {
  80                 printk("daca: failed to set volume \n");
  81                 return -1;
  82         }
  83
  84         cur_left_vol = left_vol;
  85         cur_right_vol = right_vol;
  86
  87         return 0;
  88 }
  89
  90 int daca_leave_sleep(void)
  91 {
  92         if (!daca_client)
  93                 return -1;
  94
  95         /* Do a short sleep, just to make sure I2C bus is awake and paying
  96          * attention to us
  97          */
  98         msleep(20);
  99         /* Write the sample rate reg the value it needs */
 100         i2c_smbus_write_byte_data(daca_client, 1, 8);
 101         daca_set_volume(cur_left_vol >> 5, cur_right_vol >> 5);
 102         /* Another short delay, just to make sure the other I2C bus writes
 103          * have taken...
 104          */
 105         msleep(20);
 106         /* Write the global config reg - invert right power amp,
 107          * DAC on, use 5-volt mode */
 108         i2c_smbus_write_byte_data(daca_client, 3, 0x45);
 109
 110         return 0;
 111 }
 112
 113 int daca_enter_sleep(void)
 114 {
 115         if (!daca_client)
 116                 return -1;
 117
 118         i2c_smbus_write_byte_data(daca_client, 1, 8);
 119         daca_set_volume(cur_left_vol >> 5, cur_right_vol >> 5);
 120
 121         /* Write the global config reg - invert right power amp,
 122          * DAC on, enter low-power mode, use 5-volt mode
 123          */
 124         i2c_smbus_write_byte_data(daca_client, 3, 0x65);
 125
 126         return 0;
 127 }
 128
 129 static int daca_attach_adapter(struct i2c_adapter *adapter)
 130 {
 131         if (!strncmp(adapter->name, "mac-io", 6))
 132                 daca_detect_client(adapter, 0x4d);
 133         return 0;
 134 }
 135
 136 static int daca_init_client(struct i2c_client * new_client)
 137 {
 138         /*
 139          * Probe is not working with the current i2c-keywest
 140          * driver. We try to use addr 0x4d on each adapters
 141          * instead, by setting the format register.
 142          *
 143          * FIXME: I'm sure that can be obtained from the
 144          * device-tree. --BenH.
 145          */
 146
 147         /* Write the global config reg - invert right power amp,
 148          * DAC on, use 5-volt mode
 149          */
 150         if (i2c_smbus_write_byte_data(new_client, 3, 0x45))
 151                 return -1;
 152
 153         i2c_smbus_write_byte_data(new_client, 1, 8);
 154         daca_client = new_client;
 155         daca_set_volume(15000, 15000);
 156
 157         return 0;
 158 }
 159
 160 static int daca_detect_client(struct i2c_adapter *adapter, int address)
 161 {
 162         const char *client_name = "DAC 3550A Digital Equalizer";
 163         struct i2c_client *new_client;
 164         int rc = -ENODEV;
 165
 166         new_client = kmalloc(sizeof(*new_client), GFP_KERNEL);
 167         if (!new_client)
 168                 return -ENOMEM;
 169         memset(new_client, 0, sizeof(*new_client));
 170
 171         new_client->addr = address;
 172         new_client->adapter = adapter;
 173         new_client->driver = &daca_driver;
 174         new_client->flags = 0;
 175         strcpy(new_client->name, client_name);
 176
 177         if (daca_init_client(new_client))
 178                 goto bail;
 179
 180         /* Tell the i2c layer a new client has arrived */
 181         if (i2c_attach_client(new_client))
 182                 goto bail;
 183
 184         return 0;
 185  bail:
 186         kfree(new_client);
 187         return rc;
 188 }
 189
 190
 191 static int daca_detach_client(struct i2c_client *client)
 192 {
 193         if (client == daca_client)
 194                 daca_client = NULL;
 195
 196         i2c_detach_client(client);
 197         kfree(client);
 198         return 0;
 199 }
 200
 201 void daca_cleanup(void)
 202 {
 203         i2c_del_driver(&daca_driver);
 204 }
 205
 206 int daca_init(void)
 207 {
 208         printk("dac3550a driver version %s (%s)\n",DACA_VERSION,DACA_DATE);
 209         return i2c_add_driver(&daca_driver);
 210 }