minix/drivers/audio/sb16/mixer.c
David van Moolenbroek b4d909d415 Split block/character protocols and libdriver
This patch separates the character and block driver communication
protocols. The old character protocol remains the same, but a new
block protocol is introduced. The libdriver library is replaced by
two new libraries: libchardriver and libblockdriver. Their exposed
API, and drivers that use them, have been updated accordingly.
Together, libbdev and libblockdriver now completely abstract away
the message format used by the block protocol. As the memory driver
is both a character and a block device driver, it now implements its
own message loop.

The most important semantic change made to the block protocol is that
it is no longer possible to return both partial results and an error
for a single transfer. This simplifies the interaction between the
caller and the driver, as the I/O vector no longer needs to be copied
back. Also, drivers are now no longer supposed to decide based on the
layout of the I/O vector when a transfer should be cut short. Put
simply, transfers are now supposed to either succeed completely, or
result in an error.

After this patch, the state of the various pieces is as follows:
- block protocol: stable
- libbdev API: stable for synchronous communication
- libblockdriver API: needs slight revision (the drvlib/partition API
  in particular; the threading API will also change shortly)
- character protocol: needs cleanup
- libchardriver API: needs cleanup accordingly
- driver restarts: largely unsupported until endpoint changes are
  reintroduced

As a side effect, this patch eliminates several bugs, hacks, and gcc
-Wall and -W warnings all over the place. It probably introduces a
few new ones, too.

Update warning: this patch changes the protocol between MFS and disk
drivers, so in order to use old/new images, the MFS from the ramdisk
must be used to mount all file systems.
2011-11-23 14:06:37 +01:00

253 lines
6 KiB
C

#include "sb16.h"
#include "mixer.h"
FORWARD _PROTOTYPE( int get_set_volume, (struct volume_level *level, int flag));
FORWARD _PROTOTYPE( int get_set_input, (struct inout_ctrl *input, int flag, int channel));
FORWARD _PROTOTYPE( int get_set_output, (struct inout_ctrl *output, int flag));
/*=========================================================================*
* mixer_ioctl
*=========================================================================*/
PUBLIC int mixer_ioctl(int request, void *val, int *UNUSED(len)) {
int status;
switch(request) {
case MIXIOGETVOLUME: status = get_set_volume(val, 0); break;
case MIXIOSETVOLUME: status = get_set_volume(val, 1); break;
case MIXIOGETINPUTLEFT: status = get_set_input(val, 0, 0); break;
case MIXIOGETINPUTRIGHT: status = get_set_input(val, 0, 1); break;
case MIXIOGETOUTPUT: status = get_set_output(val, 0); break;
case MIXIOSETINPUTLEFT: status = get_set_input(val, 1, 0); break;
case MIXIOSETINPUTRIGHT: status = get_set_input(val, 1, 1); break;
case MIXIOSETOUTPUT: status = get_set_output(val, 1); break;
default: status = ENOTTY;
}
return status;
}
/*=========================================================================*
* mixer_init
*=========================================================================*/
PUBLIC int mixer_init() {
/* Try to detect the mixer by writing to MIXER_DAC_LEVEL if the
* value written can be read back the mixer is there
*/
mixer_set(MIXER_DAC_LEVEL, 0x10); /* write something to it */
if(mixer_get(MIXER_DAC_LEVEL) != 0x10) {
Dprint(("sb16: Mixer not detected\n"));
return EIO;
}
/* Enable Automatic Gain Control */
mixer_set(MIXER_AGC, 0x01);
Dprint(("Mixer detected\n"));
return OK;
}
/*=========================================================================*
* get_set_volume *
*=========================================================================*/
PRIVATE int get_set_volume(struct volume_level *level, int flag) {
int cmd_left, cmd_right, shift, max_level;
shift = 3;
max_level = 0x1F;
switch(level->device) {
case Master:
cmd_left = MIXER_MASTER_LEFT;
cmd_right = MIXER_MASTER_RIGHT;
break;
case Dac:
cmd_left = MIXER_DAC_LEFT;
cmd_right = MIXER_DAC_RIGHT;
break;
case Fm:
cmd_left = MIXER_FM_LEFT;
cmd_right = MIXER_FM_RIGHT;
break;
case Cd:
cmd_left = MIXER_CD_LEFT;
cmd_right = MIXER_CD_RIGHT;
break;
case Line:
cmd_left = MIXER_LINE_LEFT;
cmd_right = MIXER_LINE_RIGHT;
break;
case Mic:
cmd_left = cmd_right = MIXER_MIC_LEVEL;
break;
case Speaker:
cmd_left = cmd_right = MIXER_PC_LEVEL;
shift = 6;
max_level = 0x03;
break;
case Treble:
cmd_left = MIXER_TREBLE_LEFT;
cmd_right = MIXER_TREBLE_RIGHT;
shift = 4;
max_level = 0x0F;
break;
case Bass:
cmd_left = MIXER_BASS_LEFT;
cmd_right = MIXER_BASS_RIGHT;
shift = 4;
max_level = 0x0F;
break;
default:
return EINVAL;
}
if(flag) { /* Set volume level */
if(level->right < 0) level->right = 0;
else if(level->right > max_level) level->right = max_level;
if(level->left < 0) level->left = 0;
else if(level->left > max_level) level->left = max_level;
mixer_set(cmd_right, (level->right << shift));
mixer_set(cmd_left, (level->left << shift));
} else { /* Get volume level */
level->left = mixer_get(cmd_left);
level->right = mixer_get(cmd_right);
level->left >>= shift;
level->right >>= shift;
}
return OK;
}
/*=========================================================================*
* get_set_input *
*=========================================================================*/
PRIVATE int get_set_input(struct inout_ctrl *input, int flag, int channel) {
int input_cmd, input_mask, mask, del_mask, shift;
input_cmd = (channel == 0 ? MIXER_IN_LEFT : MIXER_IN_RIGHT);
mask = mixer_get(input_cmd);
switch (input->device) {
case Fm:
shift = 5;
del_mask = 0x1F;
break;
case Cd:
shift = 1;
del_mask = 0x79;
break;
case Line:
shift = 3;
del_mask = 0x67;
break;
case Mic:
shift = 0;
del_mask = 0x7E;
break;
default:
return EINVAL;
}
if (flag) { /* Set input */
input_mask = ((input->left == ON ? 1 : 0) << 1) | (input->right == ON ? 1 : 0);
if (shift > 0) input_mask <<= shift;
else input_mask >>= 1;
mask &= del_mask;
mask |= input_mask;
mixer_set(input_cmd, mask);
} else { /* Get input */
if (shift > 0) {
input->left = (((mask >> (shift+1)) & 1) == 1 ? ON : OFF);
input->right = (((mask >> shift) & 1) == 1 ? ON : OFF);
} else {
input->left = ((mask & 1) == 1 ? ON : OFF);
}
}
return OK;
}
/*=========================================================================*
* get_set_output *
*=========================================================================*/
PRIVATE int get_set_output(struct inout_ctrl *output, int flag) {
int output_mask, mask, del_mask, shift;
mask = mixer_get(MIXER_OUTPUT_CTRL);
switch (output->device) {
case Cd:
shift = 1;
del_mask = 0x79;
break;
case Line:
shift = 3;
del_mask = 0x67;
break;
case Mic:
shift = 0;
del_mask = 0x7E;
break;
default:
return EINVAL;
}
if (flag) { /* Set input */
output_mask = ((output->left == ON ? 1 : 0) << 1) | (output->right == ON ? 1 : 0);
if (shift > 0) output_mask <<= shift;
else output_mask >>= 1;
mask &= del_mask;
mask |= output_mask;
mixer_set(MIXER_OUTPUT_CTRL, mask);
} else { /* Get input */
if (shift > 0) {
output->left = (((mask >> (shift+1)) & 1) == 1 ? ON : OFF);
output->right = (((mask >> shift) & 1) == 1 ? ON : OFF);
} else {
output->left = ((mask & 1) == 1 ? ON : OFF);
}
}
return OK;
}
PUBLIC int mixer_set(int reg, int data) {
int i;
sb16_outb(MIXER_REG, reg);
for(i = 0; i < 100; i++);
sb16_outb(MIXER_DATA, data);
return OK;
}
PUBLIC int mixer_get(int reg) {
int i;
sb16_outb(MIXER_REG, reg);
for(i = 0; i < 100; i++);
return sb16_inb(MIXER_DATA) & 0xff;
}