* Check the KBC command byte for kbd disable bit during keyboard probe and clean

it in case it was set "on".
* Tracing added for the case of ignoring interrupt with not active OBF status bit.

Fixes #7973 #6313



git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@42820 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/add-ons/kernel/bus_managers/ps2/ps2_common.cpp

@@ -278,8 +278,11 @@ ps2_interrupt(void* cookie)
 	ps2_dev *dev;
 
 	ctrl = ps2_read_ctrl();
-	if (!(ctrl & PS2_STATUS_OUTPUT_BUFFER_FULL))
+	if (!(ctrl & PS2_STATUS_OUTPUT_BUFFER_FULL)) {
+		TRACE("ps2: ps2_interrupt unhandled, OBF bit unset, ctrl 0x%02x (%s)\n",
+				ctrl, (ctrl & PS2_STATUS_AUX_DATA) ? "aux" : "keyb");
 		return B_UNHANDLED_INTERRUPT;
+	}
 
 	if (atomic_get(&sIgnoreInterrupts)) {
 		TRACE("ps2: ps2_interrupt ignoring, ctrl 0x%02x (%s)\n", ctrl,

src/add-ons/kernel/bus_managers/ps2/ps2_keyboard.cpp

@@ -289,6 +289,24 @@ probe_keyboard(void)
 //		return B_ERROR;
 //	}
 
+// Some controllers set the disble keyboard command bit to "on" after resetting
+// the keyboard device. Read #7973 #6313 for more details.
+// So check the command byte now and re-enable the keyboard if it is the case.
+	uint8 cmdbyte = 0;
+	status = ps2_command(PS2_CTRL_READ_CMD, NULL, 0, &cmdbyte, 1);
+
+	if (status != B_OK) {
+		INFO("ps2: cannot read CMD byte on kbd probe:0x%#08lx\n", status);
+	} else
+	if ((cmdbyte & PS2_BITS_KEYBOARD_DISABLED) == PS2_BITS_KEYBOARD_DISABLED) {
+		cmdbyte &= ~PS2_BITS_KEYBOARD_DISABLED;
+		status = ps2_command(PS2_CTRL_WRITE_CMD, &cmdbyte, 1, NULL, 0);
+		if (status != B_OK) {
+			INFO("ps2: cannot write 0x%02x to CMD byte on kbd probe:0x%08lx\n",
+					cmdbyte, status);
+		}
+	}
+
 	return B_OK;
 }