blob: c6903e9fcccb3b1d618eb29793bf861e87d6f659 (
plain) (
blame)
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
|
/*
* Copyright © 2015 Keith Packard <keithp@keithp.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*/
#ifndef _AO_ADC_FAST_H_
#define _AO_ADC_FAST_H_
void
ao_adc_read(uint16_t *dest, int len);
void
ao_adc_init(void);
/* Total ring size in samples */
#define AO_ADC_RING_SIZE 256
extern uint16_t ao_adc_ring[AO_ADC_RING_SIZE];
#define ao_adc_ring_step(pos,inc) (((pos) + (inc)) & (AO_ADC_RING_SIZE - 1))
extern uint16_t ao_adc_ring_head, ao_adc_ring_remain;
extern uint16_t ao_adc_running;
/*
* Place to start fetching values from
*/
static inline uint16_t
ao_adc_ring_tail(void)
{
return (ao_adc_ring_head - ao_adc_ring_remain) & (AO_ADC_RING_SIZE - 1);
}
void
_ao_adc_start(void);
/*
* Space available to write ADC values into
*/
static inline uint16_t
_ao_adc_space(void)
{
/* Free to end of buffer? */
if (ao_adc_ring_remain <= ao_adc_ring_head)
return AO_ADC_RING_SIZE - ao_adc_ring_head;
/* no, return just the unused entries beyond head */
return AO_ADC_RING_SIZE - ao_adc_ring_remain;
}
static inline uint16_t
ao_adc_get(uint16_t n)
{
ao_arch_block_interrupts();
while (ao_adc_ring_remain < n) {
if (!ao_adc_running)
_ao_adc_start();
ao_sleep(&ao_adc_ring_head);
}
ao_arch_release_interrupts();
return ao_adc_ring_tail();
}
static inline void
ao_adc_ack(uint16_t n)
{
ao_arch_block_interrupts();
ao_adc_ring_remain -= n;
if (!ao_adc_running)
_ao_adc_start();
ao_arch_release_interrupts();
}
#endif /* _AO_ADC_FAST_H_ */
|
