diff options
| -rw-r--r-- | hw/misc/mac_via.c | 78 |
1 files changed, 27 insertions, 51 deletions
diff --git a/hw/misc/mac_via.c b/hw/misc/mac_via.c index 8810eb97cc..4914cb8098 100644 --- a/hw/misc/mac_via.c +++ b/hw/misc/mac_via.c @@ -609,7 +609,6 @@ static void adb_via_poll(void *opaque) uint8_t obuf[9]; uint8_t *data = &s->sr; int olen; - uint16_t pending; /* * Setting vADBInt below indicates that an autopoll reply has been @@ -618,36 +617,36 @@ static void adb_via_poll(void *opaque) */ adb_autopoll_block(adb_bus); - m->adb_data_in_index = 0; - m->adb_data_out_index = 0; - olen = adb_poll(adb_bus, obuf, adb_bus->autopoll_mask); - - if (olen > 0) { - /* Autopoll response */ - *data = obuf[0]; - olen--; - memcpy(m->adb_data_in, &obuf[1], olen); - m->adb_data_in_size = olen; + if (m->adb_data_in_size > 0 && m->adb_data_in_index == 0) { + /* + * For older Linux kernels that switch to IDLE mode after sending the + * ADB command, detect if there is an existing response and return that + * as a a "fake" autopoll reply or bus timeout accordingly + */ + *data = m->adb_data_out[0]; + olen = m->adb_data_in_size; s->b &= ~VIA1B_vADBInt; qemu_irq_raise(m->adb_data_ready); - } else if (olen < 0) { - /* Bus timeout (device does not exist) */ - *data = 0xff; - s->b |= VIA1B_vADBInt; - adb_autopoll_unblock(adb_bus); } else { - pending = adb_bus->pending & ~(1 << (m->adb_autopoll_cmd >> 4)); + /* + * Otherwise poll as normal + */ + m->adb_data_in_index = 0; + m->adb_data_out_index = 0; + olen = adb_poll(adb_bus, obuf, adb_bus->autopoll_mask); + + if (olen > 0) { + /* Autopoll response */ + *data = obuf[0]; + olen--; + memcpy(m->adb_data_in, &obuf[1], olen); + m->adb_data_in_size = olen; - if (pending) { - /* - * Bus timeout (device exists but another device has data). Block - * autopoll so the OS can read out the first EVEN and first ODD - * byte to determine bus timeout and SRQ status - */ - *data = m->adb_autopoll_cmd; s->b &= ~VIA1B_vADBInt; - + qemu_irq_raise(m->adb_data_ready); + } else { + *data = m->adb_autopoll_cmd; obuf[0] = 0xff; obuf[1] = 0xff; olen = 2; @@ -655,12 +654,8 @@ static void adb_via_poll(void *opaque) memcpy(m->adb_data_in, obuf, olen); m->adb_data_in_size = olen; + s->b &= ~VIA1B_vADBInt; qemu_irq_raise(m->adb_data_ready); - } else { - /* Bus timeout (device exists but no other device has data) */ - *data = 0; - s->b |= VIA1B_vADBInt; - adb_autopoll_unblock(adb_bus); } } @@ -783,27 +778,8 @@ static void adb_via_receive(MacVIAState *s, int state, uint8_t *data) return; case ADB_STATE_IDLE: - /* - * Since adb_request() will have already consumed the data from the - * device, we must detect this extra state change and re-inject the - * reponse as either a "fake" autopoll reply or bus timeout - * accordingly - */ - if (s->adb_data_in_index == 0) { - if (adb_bus->status & ADB_STATUS_BUSTIMEOUT) { - *data = 0xff; - ms->b |= VIA1B_vADBInt; - qemu_irq_raise(s->adb_data_ready); - } else if (s->adb_data_in_size > 0) { - adb_bus->status = ADB_STATUS_POLLREPLY; - *data = s->adb_autopoll_cmd; - ms->b &= ~VIA1B_vADBInt; - qemu_irq_raise(s->adb_data_ready); - } - } else { - ms->b |= VIA1B_vADBInt; - adb_autopoll_unblock(adb_bus); - } + ms->b |= VIA1B_vADBInt; + adb_autopoll_unblock(adb_bus); trace_via1_adb_receive("IDLE", *data, (ms->b & VIA1B_vADBInt) ? "+" : "-", adb_bus->status, |