balrog | adb86c3 | 2007-05-23 22:04:23 +0000 | [diff] [blame] | 1 | /* |
| 2 | * MAX7310 8-port GPIO expansion chip. |
| 3 | * |
| 4 | * Copyright (c) 2006 Openedhand Ltd. |
| 5 | * Written by Andrzej Zaborowski <balrog@zabor.org> |
| 6 | * |
| 7 | * This file is licensed under GNU GPL. |
| 8 | */ |
| 9 | |
pbrook | 87ecb68 | 2007-11-17 17:14:51 +0000 | [diff] [blame] | 10 | #include "hw.h" |
| 11 | #include "i2c.h" |
balrog | adb86c3 | 2007-05-23 22:04:23 +0000 | [diff] [blame] | 12 | |
| 13 | struct max7310_s { |
| 14 | i2c_slave i2c; |
| 15 | int i2c_command_byte; |
| 16 | int len; |
| 17 | |
| 18 | uint8_t level; |
| 19 | uint8_t direction; |
| 20 | uint8_t polarity; |
| 21 | uint8_t status; |
| 22 | uint8_t command; |
| 23 | qemu_irq handler[8]; |
| 24 | qemu_irq *gpio_in; |
| 25 | }; |
| 26 | |
| 27 | void max7310_reset(i2c_slave *i2c) |
| 28 | { |
| 29 | struct max7310_s *s = (struct max7310_s *) i2c; |
| 30 | s->level &= s->direction; |
| 31 | s->direction = 0xff; |
| 32 | s->polarity = 0xf0; |
| 33 | s->status = 0x01; |
| 34 | s->command = 0x00; |
| 35 | } |
| 36 | |
| 37 | static int max7310_rx(i2c_slave *i2c) |
| 38 | { |
| 39 | struct max7310_s *s = (struct max7310_s *) i2c; |
| 40 | |
| 41 | switch (s->command) { |
| 42 | case 0x00: /* Input port */ |
| 43 | return s->level ^ s->polarity; |
| 44 | break; |
| 45 | |
| 46 | case 0x01: /* Output port */ |
| 47 | return s->level & ~s->direction; |
| 48 | break; |
| 49 | |
| 50 | case 0x02: /* Polarity inversion */ |
| 51 | return s->polarity; |
| 52 | |
| 53 | case 0x03: /* Configuration */ |
| 54 | return s->direction; |
| 55 | |
| 56 | case 0x04: /* Timeout */ |
| 57 | return s->status; |
| 58 | break; |
| 59 | |
| 60 | case 0xff: /* Reserved */ |
| 61 | return 0xff; |
| 62 | |
| 63 | default: |
| 64 | #ifdef VERBOSE |
| 65 | printf("%s: unknown register %02x\n", __FUNCTION__, s->command); |
| 66 | #endif |
| 67 | break; |
| 68 | } |
| 69 | return 0xff; |
| 70 | } |
| 71 | |
| 72 | static int max7310_tx(i2c_slave *i2c, uint8_t data) |
| 73 | { |
| 74 | struct max7310_s *s = (struct max7310_s *) i2c; |
| 75 | uint8_t diff; |
| 76 | int line; |
| 77 | |
| 78 | if (s->len ++ > 1) { |
| 79 | #ifdef VERBOSE |
| 80 | printf("%s: message too long (%i bytes)\n", __FUNCTION__, s->len); |
| 81 | #endif |
| 82 | return 1; |
| 83 | } |
| 84 | |
| 85 | if (s->i2c_command_byte) { |
| 86 | s->command = data; |
| 87 | s->i2c_command_byte = 0; |
| 88 | return 0; |
| 89 | } |
| 90 | |
| 91 | switch (s->command) { |
| 92 | case 0x01: /* Output port */ |
| 93 | for (diff = (data ^ s->level) & ~s->direction; diff; |
| 94 | diff &= ~(1 << line)) { |
| 95 | line = ffs(diff) - 1; |
| 96 | if (s->handler[line]) |
| 97 | qemu_set_irq(s->handler[line], (data >> line) & 1); |
| 98 | } |
| 99 | s->level = (s->level & s->direction) | (data & ~s->direction); |
| 100 | break; |
| 101 | |
| 102 | case 0x02: /* Polarity inversion */ |
| 103 | s->polarity = data; |
| 104 | break; |
| 105 | |
| 106 | case 0x03: /* Configuration */ |
| 107 | s->level &= ~(s->direction ^ data); |
| 108 | s->direction = data; |
| 109 | break; |
| 110 | |
| 111 | case 0x04: /* Timeout */ |
| 112 | s->status = data; |
| 113 | break; |
| 114 | |
| 115 | case 0x00: /* Input port - ignore writes */ |
| 116 | break; |
| 117 | default: |
| 118 | #ifdef VERBOSE |
| 119 | printf("%s: unknown register %02x\n", __FUNCTION__, s->command); |
| 120 | #endif |
| 121 | return 1; |
| 122 | } |
| 123 | |
| 124 | return 0; |
| 125 | } |
| 126 | |
| 127 | static void max7310_event(i2c_slave *i2c, enum i2c_event event) |
| 128 | { |
| 129 | struct max7310_s *s = (struct max7310_s *) i2c; |
| 130 | s->len = 0; |
| 131 | |
| 132 | switch (event) { |
| 133 | case I2C_START_SEND: |
| 134 | s->i2c_command_byte = 1; |
| 135 | break; |
| 136 | case I2C_FINISH: |
balrog | adb86c3 | 2007-05-23 22:04:23 +0000 | [diff] [blame] | 137 | #ifdef VERBOSE |
balrog | e62ab7a | 2008-05-09 22:17:18 +0000 | [diff] [blame] | 138 | if (s->len == 1) |
balrog | adb86c3 | 2007-05-23 22:04:23 +0000 | [diff] [blame] | 139 | printf("%s: message too short (%i bytes)\n", __FUNCTION__, s->len); |
| 140 | #endif |
| 141 | break; |
| 142 | default: |
| 143 | break; |
| 144 | } |
| 145 | } |
| 146 | |
balrog | aa941b9 | 2007-05-24 18:50:09 +0000 | [diff] [blame] | 147 | static void max7310_save(QEMUFile *f, void *opaque) |
| 148 | { |
| 149 | struct max7310_s *s = (struct max7310_s *) opaque; |
| 150 | |
| 151 | qemu_put_be32(f, s->i2c_command_byte); |
| 152 | qemu_put_be32(f, s->len); |
| 153 | |
| 154 | qemu_put_8s(f, &s->level); |
| 155 | qemu_put_8s(f, &s->direction); |
| 156 | qemu_put_8s(f, &s->polarity); |
| 157 | qemu_put_8s(f, &s->status); |
| 158 | qemu_put_8s(f, &s->command); |
| 159 | |
| 160 | i2c_slave_save(f, &s->i2c); |
| 161 | } |
| 162 | |
| 163 | static int max7310_load(QEMUFile *f, void *opaque, int version_id) |
| 164 | { |
| 165 | struct max7310_s *s = (struct max7310_s *) opaque; |
| 166 | |
| 167 | s->i2c_command_byte = qemu_get_be32(f); |
| 168 | s->len = qemu_get_be32(f); |
| 169 | |
| 170 | qemu_get_8s(f, &s->level); |
| 171 | qemu_get_8s(f, &s->direction); |
| 172 | qemu_get_8s(f, &s->polarity); |
| 173 | qemu_get_8s(f, &s->status); |
| 174 | qemu_get_8s(f, &s->command); |
| 175 | |
| 176 | i2c_slave_load(f, &s->i2c); |
| 177 | return 0; |
| 178 | } |
| 179 | |
balrog | adb86c3 | 2007-05-23 22:04:23 +0000 | [diff] [blame] | 180 | static void max7310_gpio_set(void *opaque, int line, int level) |
| 181 | { |
| 182 | struct max7310_s *s = (struct max7310_s *) opaque; |
| 183 | if (line >= sizeof(s->handler) / sizeof(*s->handler) || line < 0) |
pbrook | 87ecb68 | 2007-11-17 17:14:51 +0000 | [diff] [blame] | 184 | hw_error("bad GPIO line"); |
balrog | adb86c3 | 2007-05-23 22:04:23 +0000 | [diff] [blame] | 185 | |
| 186 | if (level) |
| 187 | s->level |= s->direction & (1 << line); |
| 188 | else |
| 189 | s->level &= ~(s->direction & (1 << line)); |
| 190 | } |
| 191 | |
| 192 | /* MAX7310 is SMBus-compatible (can be used with only SMBus protocols), |
| 193 | * but also accepts sequences that are not SMBus so return an I2C device. */ |
| 194 | struct i2c_slave *max7310_init(i2c_bus *bus) |
| 195 | { |
| 196 | struct max7310_s *s = (struct max7310_s *) |
| 197 | i2c_slave_init(bus, 0, sizeof(struct max7310_s)); |
| 198 | s->i2c.event = max7310_event; |
| 199 | s->i2c.recv = max7310_rx; |
| 200 | s->i2c.send = max7310_tx; |
| 201 | s->gpio_in = qemu_allocate_irqs(max7310_gpio_set, s, |
| 202 | sizeof(s->handler) / sizeof(*s->handler)); |
| 203 | |
| 204 | max7310_reset(&s->i2c); |
| 205 | |
pbrook | 18be518 | 2008-07-01 21:31:54 +0000 | [diff] [blame] | 206 | register_savevm("max7310", -1, 0, max7310_save, max7310_load, s); |
balrog | aa941b9 | 2007-05-24 18:50:09 +0000 | [diff] [blame] | 207 | |
balrog | adb86c3 | 2007-05-23 22:04:23 +0000 | [diff] [blame] | 208 | return &s->i2c; |
| 209 | } |
| 210 | |
| 211 | qemu_irq *max7310_gpio_in_get(i2c_slave *i2c) |
| 212 | { |
| 213 | struct max7310_s *s = (struct max7310_s *) i2c; |
| 214 | return s->gpio_in; |
| 215 | } |
| 216 | |
| 217 | void max7310_gpio_out_set(i2c_slave *i2c, int line, qemu_irq handler) |
| 218 | { |
| 219 | struct max7310_s *s = (struct max7310_s *) i2c; |
| 220 | if (line >= sizeof(s->handler) / sizeof(*s->handler) || line < 0) |
pbrook | 87ecb68 | 2007-11-17 17:14:51 +0000 | [diff] [blame] | 221 | hw_error("bad GPIO line"); |
balrog | adb86c3 | 2007-05-23 22:04:23 +0000 | [diff] [blame] | 222 | |
| 223 | s->handler[line] = handler; |
| 224 | } |