+/*
+ * psmouse_poll() - default poll hanlder. Everyone except for ALPS uses it.
+ */
+
+static int psmouse_poll(struct psmouse *psmouse)
+{
+ return ps2_command(&psmouse->ps2dev, psmouse->packet,
+ PSMOUSE_CMD_POLL | (psmouse->pktsize << 8));
+}
+
+
+/*
+ * psmouse_resync() attempts to re-validate current protocol.
+ */
+
+static void psmouse_resync(void *p)
+{
+ struct psmouse *psmouse = p, *parent = NULL;
+ struct serio *serio = psmouse->ps2dev.serio;
+ psmouse_ret_t rc = PSMOUSE_GOOD_DATA;
+ int failed = 0, enabled = 0;
+ int i;
+
+ mutex_lock(&psmouse_mutex);
+
+ if (psmouse->state != PSMOUSE_RESYNCING)
+ goto out;
+
+ if (serio->parent && serio->id.type == SERIO_PS_PSTHRU) {
+ parent = serio_get_drvdata(serio->parent);
+ psmouse_deactivate(parent);
+ }
+
+/*
+ * Some mice don't ACK commands sent while they are in the middle of
+ * transmitting motion packet. To avoid delay we use ps2_sendbyte()
+ * instead of ps2_command() which would wait for 200ms for an ACK
+ * that may never come.
+ * As an additional quirk ALPS touchpads may not only forget to ACK
+ * disable command but will stop reporting taps, so if we see that
+ * mouse at least once ACKs disable we will do full reconnect if ACK
+ * is missing.
+ */
+ psmouse->num_resyncs++;
+
+ if (ps2_sendbyte(&psmouse->ps2dev, PSMOUSE_CMD_DISABLE, 20)) {
+ if (psmouse->num_resyncs < 3 || psmouse->acks_disable_command)
+ failed = 1;
+ } else
+ psmouse->acks_disable_command = 1;
+
+/*
+ * Poll the mouse. If it was reset the packet will be shorter than
+ * psmouse->pktsize and ps2_command will fail. We do not expect and
+ * do not handle scenario when mouse "upgrades" its protocol while
+ * disconnected since it would require additional delay. If we ever
+ * see a mouse that does it we'll adjust the code.
+ */
+ if (!failed) {
+ if (psmouse->poll(psmouse))
+ failed = 1;
+ else {
+ psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
+ for (i = 0; i < psmouse->pktsize; i++) {
+ psmouse->pktcnt++;
+ rc = psmouse->protocol_handler(psmouse, NULL);
+ if (rc != PSMOUSE_GOOD_DATA)
+ break;
+ }
+ if (rc != PSMOUSE_FULL_PACKET)
+ failed = 1;
+ psmouse_set_state(psmouse, PSMOUSE_RESYNCING);
+ }
+ }
+/*
+ * Now try to enable mouse. We try to do that even if poll failed and also
+ * repeat our attempts 5 times, otherwise we may be left out with disabled
+ * mouse.
+ */
+ for (i = 0; i < 5; i++) {
+ if (!ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_ENABLE)) {
+ enabled = 1;
+ break;
+ }
+ msleep(200);
+ }
+
+ if (!enabled) {
+ printk(KERN_WARNING "psmouse.c: failed to re-enable mouse on %s\n",
+ psmouse->ps2dev.serio->phys);
+ failed = 1;
+ }
+
+ if (failed) {
+ psmouse_set_state(psmouse, PSMOUSE_IGNORE);
+ printk(KERN_INFO "psmouse.c: resync failed, issuing reconnect request\n");
+ serio_reconnect(serio);
+ } else
+ psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);
+
+ if (parent)
+ psmouse_activate(parent);
+ out:
+ mutex_unlock(&psmouse_mutex);
+}