adb: fix adb-mouse read length and revert disable-reg3-direct-writes workaround

Commit 84051eb400 "adb: add property to disable direct reg 3 writes" introduced
a workaround for spurious writes to ADB register 3 when MacOS 9 enables
autopoll on the mouse device. Further analysis shows that the problem is that
only a partial request is sent, and since the len parameter is ignored then
stale data from the previous request is used causing the incorrect address
assignment.

Remove the disable-reg3-direct-writes workaround and instead check the length
parameter when the write is attempted, discarding the invalid request.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Tested-by: Finn Thain <fthain@telegraphics.com.au>
Acked-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20200623204936.24064-3-mark.cave-ayland@ilande.co.uk>
This commit is contained in:
Mark Cave-Ayland 2020-06-23 21:49:16 +01:00
parent bcaaefdbb2
commit 167f1667b1
5 changed files with 40 additions and 44 deletions

View File

@ -259,21 +259,19 @@ static int adb_kbd_request(ADBDevice *d, uint8_t *obuf,
trace_adb_kbd_request_change_addr(d->devaddr);
break;
default:
if (!d->disable_direct_reg3_writes) {
d->devaddr = buf[1] & 0xf;
/* we support handlers:
* 1: Apple Standard Keyboard
* 2: Apple Extended Keyboard (LShift = RShift)
* 3: Apple Extended Keyboard (LShift != RShift)
*/
if (buf[2] == 1 || buf[2] == 2 || buf[2] == 3) {
d->handler = buf[2];
}
trace_adb_kbd_request_change_addr_and_handler(d->devaddr,
d->handler);
d->devaddr = buf[1] & 0xf;
/*
* we support handlers:
* 1: Apple Standard Keyboard
* 2: Apple Extended Keyboard (LShift = RShift)
* 3: Apple Extended Keyboard (LShift != RShift)
*/
if (buf[2] == 1 || buf[2] == 2 || buf[2] == 3) {
d->handler = buf[2];
}
trace_adb_kbd_request_change_addr_and_handler(d->devaddr,
d->handler);
break;
}
}

View File

@ -135,6 +135,16 @@ static int adb_mouse_request(ADBDevice *d, uint8_t *obuf,
case 2:
break;
case 3:
/*
* MacOS 9 has a bug in its ADB driver whereby after configuring
* the ADB bus devices it sends another write of invalid length
* to reg 3. Make sure we ignore it to prevent an address clash
* with the previous device.
*/
if (len != 3) {
return 0;
}
switch (buf[2]) {
case ADB_CMD_SELF_TEST:
break;
@ -145,27 +155,25 @@ static int adb_mouse_request(ADBDevice *d, uint8_t *obuf,
trace_adb_mouse_request_change_addr(d->devaddr);
break;
default:
if (!d->disable_direct_reg3_writes) {
d->devaddr = buf[1] & 0xf;
/* we support handlers:
* 0x01: Classic Apple Mouse Protocol / 100 cpi operations
* 0x02: Classic Apple Mouse Protocol / 200 cpi operations
* we don't support handlers (at least):
* 0x03: Mouse systems A3 trackball
* 0x04: Extended Apple Mouse Protocol
* 0x2f: Microspeed mouse
* 0x42: Macally
* 0x5f: Microspeed mouse
* 0x66: Microspeed mouse
*/
if (buf[2] == 1 || buf[2] == 2) {
d->handler = buf[2];
}
trace_adb_mouse_request_change_addr_and_handler(
d->devaddr, d->handler);
d->devaddr = buf[1] & 0xf;
/*
* we support handlers:
* 0x01: Classic Apple Mouse Protocol / 100 cpi operations
* 0x02: Classic Apple Mouse Protocol / 200 cpi operations
* we don't support handlers (at least):
* 0x03: Mouse systems A3 trackball
* 0x04: Extended Apple Mouse Protocol
* 0x2f: Microspeed mouse
* 0x42: Macally
* 0x5f: Microspeed mouse
* 0x66: Microspeed mouse
*/
if (buf[2] == 1 || buf[2] == 2) {
d->handler = buf[2];
}
trace_adb_mouse_request_change_addr_and_handler(d->devaddr,
d->handler);
break;
}
}

View File

@ -118,18 +118,11 @@ static void adb_device_realizefn(DeviceState *dev, Error **errp)
bus->devices[bus->nb_devices++] = d;
}
static Property adb_device_properties[] = {
DEFINE_PROP_BOOL("disable-direct-reg3-writes", ADBDevice,
disable_direct_reg3_writes, false),
DEFINE_PROP_END_OF_LIST(),
};
static void adb_device_class_init(ObjectClass *oc, void *data)
{
DeviceClass *dc = DEVICE_CLASS(oc);
dc->realize = adb_device_realizefn;
device_class_set_props(dc, adb_device_properties);
dc->bus_type = TYPE_ADB_BUS;
}

View File

@ -404,11 +404,9 @@ static void ppc_core99_init(MachineState *machine)
adb_bus = qdev_get_child_bus(dev, "adb.0");
dev = qdev_new(TYPE_ADB_KEYBOARD);
qdev_prop_set_bit(dev, "disable-direct-reg3-writes", true);
qdev_realize_and_unref(dev, adb_bus, &error_fatal);
dev = qdev_new(TYPE_ADB_MOUSE);
qdev_prop_set_bit(dev, "disable-direct-reg3-writes", true);
qdev_realize_and_unref(dev, adb_bus, &error_fatal);
}

View File

@ -49,7 +49,6 @@ struct ADBDevice {
int devaddr;
int handler;
bool disable_direct_reg3_writes;
};
#define ADB_DEVICE_CLASS(cls) \