balrog | c824cac | 2007-04-30 02:14:00 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Maxim MAX1110/1111 ADC chip emulation. |
| 3 | * |
| 4 | * Copyright (c) 2006 Openedhand Ltd. |
| 5 | * Written by Andrzej Zaborowski <balrog@zabor.org> |
| 6 | * |
| 7 | * This code is licensed under the GNU GPLv2. |
| 8 | */ |
| 9 | |
pbrook | 87ecb68 | 2007-11-17 17:14:51 +0000 | [diff] [blame] | 10 | #include "hw.h" |
| 11 | #include "i2c.h" |
balrog | c824cac | 2007-04-30 02:14:00 +0000 | [diff] [blame] | 12 | |
| 13 | struct max111x_s { |
| 14 | qemu_irq interrupt; |
| 15 | uint8_t tb1, rb2, rb3; |
| 16 | int cycle; |
| 17 | |
| 18 | int input[8]; |
| 19 | int inputs, com; |
| 20 | }; |
| 21 | |
| 22 | /* Control-byte bitfields */ |
| 23 | #define CB_PD0 (1 << 0) |
| 24 | #define CB_PD1 (1 << 1) |
| 25 | #define CB_SGL (1 << 2) |
| 26 | #define CB_UNI (1 << 3) |
| 27 | #define CB_SEL0 (1 << 4) |
| 28 | #define CB_SEL1 (1 << 5) |
| 29 | #define CB_SEL2 (1 << 6) |
| 30 | #define CB_START (1 << 7) |
| 31 | |
| 32 | #define CHANNEL_NUM(v, b0, b1, b2) \ |
| 33 | ((((v) >> (2 + (b0))) & 4) | \ |
| 34 | (((v) >> (3 + (b1))) & 2) | \ |
| 35 | (((v) >> (4 + (b2))) & 1)) |
| 36 | |
| 37 | uint32_t max111x_read(void *opaque) |
| 38 | { |
| 39 | struct max111x_s *s = (struct max111x_s *) opaque; |
| 40 | |
| 41 | if (!s->tb1) |
| 42 | return 0; |
| 43 | |
| 44 | switch (s->cycle ++) { |
| 45 | case 1: |
| 46 | return s->rb2; |
| 47 | case 2: |
| 48 | return s->rb3; |
| 49 | } |
| 50 | |
| 51 | return 0; |
| 52 | } |
| 53 | |
| 54 | /* Interpret a control-byte */ |
| 55 | void max111x_write(void *opaque, uint32_t value) |
| 56 | { |
| 57 | struct max111x_s *s = (struct max111x_s *) opaque; |
| 58 | int measure, chan; |
| 59 | |
| 60 | /* Ignore the value if START bit is zero */ |
| 61 | if (!(value & CB_START)) |
| 62 | return; |
| 63 | |
| 64 | s->cycle = 0; |
| 65 | |
| 66 | if (!(value & CB_PD1)) { |
| 67 | s->tb1 = 0; |
| 68 | return; |
| 69 | } |
| 70 | |
| 71 | s->tb1 = value; |
| 72 | |
| 73 | if (s->inputs == 8) |
| 74 | chan = CHANNEL_NUM(value, 1, 0, 2); |
| 75 | else |
| 76 | chan = CHANNEL_NUM(value & ~CB_SEL0, 0, 1, 2); |
| 77 | |
| 78 | if (value & CB_SGL) |
| 79 | measure = s->input[chan] - s->com; |
| 80 | else |
| 81 | measure = s->input[chan] - s->input[chan ^ 1]; |
| 82 | |
| 83 | if (!(value & CB_UNI)) |
| 84 | measure ^= 0x80; |
| 85 | |
| 86 | s->rb2 = (measure >> 2) & 0x3f; |
| 87 | s->rb3 = (measure << 6) & 0xc0; |
| 88 | |
| 89 | if (s->interrupt) |
| 90 | qemu_irq_raise(s->interrupt); |
| 91 | } |
| 92 | |
balrog | aa941b9 | 2007-05-24 18:50:09 +0000 | [diff] [blame] | 93 | static void max111x_save(QEMUFile *f, void *opaque) |
| 94 | { |
| 95 | struct max111x_s *s = (struct max111x_s *) opaque; |
| 96 | int i; |
| 97 | |
| 98 | qemu_put_8s(f, &s->tb1); |
| 99 | qemu_put_8s(f, &s->rb2); |
| 100 | qemu_put_8s(f, &s->rb3); |
| 101 | qemu_put_be32(f, s->inputs); |
| 102 | qemu_put_be32(f, s->com); |
| 103 | for (i = 0; i < s->inputs; i ++) |
| 104 | qemu_put_byte(f, s->input[i]); |
| 105 | } |
| 106 | |
| 107 | static int max111x_load(QEMUFile *f, void *opaque, int version_id) |
| 108 | { |
| 109 | struct max111x_s *s = (struct max111x_s *) opaque; |
| 110 | int i; |
| 111 | |
| 112 | qemu_get_8s(f, &s->tb1); |
| 113 | qemu_get_8s(f, &s->rb2); |
| 114 | qemu_get_8s(f, &s->rb3); |
| 115 | if (s->inputs != qemu_get_be32(f)) |
| 116 | return -EINVAL; |
| 117 | s->com = qemu_get_be32(f); |
| 118 | for (i = 0; i < s->inputs; i ++) |
| 119 | s->input[i] = qemu_get_byte(f); |
| 120 | |
| 121 | return 0; |
| 122 | } |
| 123 | |
balrog | c824cac | 2007-04-30 02:14:00 +0000 | [diff] [blame] | 124 | static struct max111x_s *max111x_init(qemu_irq cb) |
| 125 | { |
| 126 | struct max111x_s *s; |
| 127 | s = (struct max111x_s *) |
| 128 | qemu_mallocz(sizeof(struct max111x_s)); |
| 129 | memset(s, 0, sizeof(struct max111x_s)); |
| 130 | |
| 131 | s->interrupt = cb; |
| 132 | |
| 133 | /* TODO: add a user interface for setting these */ |
| 134 | s->input[0] = 0xf0; |
| 135 | s->input[1] = 0xe0; |
| 136 | s->input[2] = 0xd0; |
| 137 | s->input[3] = 0xc0; |
| 138 | s->input[4] = 0xb0; |
| 139 | s->input[5] = 0xa0; |
| 140 | s->input[6] = 0x90; |
| 141 | s->input[7] = 0x80; |
| 142 | s->com = 0; |
balrog | aa941b9 | 2007-05-24 18:50:09 +0000 | [diff] [blame] | 143 | |
pbrook | 18be518 | 2008-07-01 21:31:54 +0000 | [diff] [blame] | 144 | register_savevm("max111x", -1, 0, max111x_save, max111x_load, s); |
balrog | aa941b9 | 2007-05-24 18:50:09 +0000 | [diff] [blame] | 145 | |
balrog | c824cac | 2007-04-30 02:14:00 +0000 | [diff] [blame] | 146 | return s; |
| 147 | } |
| 148 | |
| 149 | struct max111x_s *max1110_init(qemu_irq cb) |
| 150 | { |
| 151 | struct max111x_s *s = max111x_init(cb); |
| 152 | s->inputs = 8; |
| 153 | return s; |
| 154 | } |
| 155 | |
| 156 | struct max111x_s *max1111_init(qemu_irq cb) |
| 157 | { |
| 158 | struct max111x_s *s = max111x_init(cb); |
| 159 | s->inputs = 4; |
| 160 | return s; |
| 161 | } |
| 162 | |
| 163 | void max111x_set_input(struct max111x_s *s, int line, uint8_t value) |
| 164 | { |
| 165 | if (line >= s->inputs) { |
| 166 | printf("%s: There's no input %i\n", __FUNCTION__, line); |
| 167 | return; |
| 168 | } |
| 169 | |
| 170 | s->input[line] = value; |
| 171 | } |