-/* Handle case where mt_state->count = 0 */
-static void synaptics_image_sensor_0f(struct synaptics_data *priv,
- struct synaptics_mt_state *mt_state)
-{
- synaptics_mt_state_set(mt_state, 0, -1, -1);
- priv->mt_state_lost = false;
-}
-
-/* Handle case where mt_state->count = 1 */
-static void synaptics_image_sensor_1f(struct synaptics_data *priv,
- struct synaptics_mt_state *mt_state)
-{
- struct synaptics_hw_state *agm = &priv->agm;
- struct synaptics_mt_state *old = &priv->mt_state;
-
- /*
- * If the last AGM was (0,0,0), and there is only one finger left,
- * then we absolutely know that SGM contains slot 0, and all other
- * fingers have been removed.
- */
- if (priv->agm_pending && agm->z == 0) {
- synaptics_mt_state_set(mt_state, 1, 0, -1);
- priv->mt_state_lost = false;
- return;
- }
-
- switch (old->count) {
- case 0:
- synaptics_mt_state_set(mt_state, 1, 0, -1);
- break;
- case 1:
- /*
- * If mt_state_lost, then the previous transition was 3->1,
- * and SGM now contains either slot 0 or 1, but we don't know
- * which. So, we just assume that the SGM now contains slot 1.
- *
- * If pending AGM and either:
- * (a) the previous SGM slot contains slot 0, or
- * (b) there was no SGM slot
- * then, the SGM now contains slot 1
- *
- * Case (a) happens with very rapid "drum roll" gestures, where
- * slot 0 finger is lifted and a new slot 1 finger touches
- * within one reporting interval.
- *
- * Case (b) happens if initially two or more fingers tap
- * briefly, and all but one lift before the end of the first
- * reporting interval.
- *
- * (In both these cases, slot 0 will becomes empty, so SGM
- * contains slot 1 with the new finger)
- *
- * Else, if there was no previous SGM, it now contains slot 0.
- *
- * Otherwise, SGM still contains the same slot.
- */
- if (priv->mt_state_lost ||
- (priv->agm_pending && old->sgm <= 0))
- synaptics_mt_state_set(mt_state, 1, 1, -1);
- else if (old->sgm == -1)
- synaptics_mt_state_set(mt_state, 1, 0, -1);
- break;
- case 2:
- /*
- * If mt_state_lost, we don't know which finger SGM contains.
- *
- * So, report 1 finger, but with both slots empty.
- * We will use slot 1 on subsequent 1->1
- */
- if (priv->mt_state_lost) {
- synaptics_mt_state_set(mt_state, 1, -1, -1);
- break;
- }
- /*
- * Since the last AGM was NOT (0,0,0), it was the finger in
- * slot 0 that has been removed.
- * So, SGM now contains previous AGM's slot, and AGM is now
- * empty.
- */
- synaptics_mt_state_set(mt_state, 1, old->agm, -1);
- break;
- case 3:
- /*
- * Since last AGM was not (0,0,0), we don't know which finger
- * is left.
- *
- * So, report 1 finger, but with both slots empty.
- * We will use slot 1 on subsequent 1->1
- */
- synaptics_mt_state_set(mt_state, 1, -1, -1);
- priv->mt_state_lost = true;
- break;
- case 4:
- case 5:
- /* mt_state was updated by AGM-CONTACT packet */
- break;
- }
-}
-
-/* Handle case where mt_state->count = 2 */
-static void synaptics_image_sensor_2f(struct synaptics_data *priv,
- struct synaptics_mt_state *mt_state)
-{
- struct synaptics_mt_state *old = &priv->mt_state;
-
- switch (old->count) {
- case 0:
- synaptics_mt_state_set(mt_state, 2, 0, 1);
- break;
- case 1:
- /*
- * If previous SGM contained slot 1 or higher, SGM now contains
- * slot 0 (the newly touching finger) and AGM contains SGM's
- * previous slot.
- *
- * Otherwise, SGM still contains slot 0 and AGM now contains
- * slot 1.
- */
- if (old->sgm >= 1)
- synaptics_mt_state_set(mt_state, 2, 0, old->sgm);
- else
- synaptics_mt_state_set(mt_state, 2, 0, 1);
- break;
- case 2:
- /*
- * If mt_state_lost, SGM now contains either finger 1 or 2, but
- * we don't know which.
- * So, we just assume that the SGM contains slot 0 and AGM 1.
- */
- if (priv->mt_state_lost)
- synaptics_mt_state_set(mt_state, 2, 0, 1);
- /*
- * Otherwise, use the same mt_state, since it either hasn't
- * changed, or was updated by a recently received AGM-CONTACT
- * packet.
- */
- break;
- case 3:
- /*
- * 3->2 transitions have two unsolvable problems:
- * 1) no indication is given which finger was removed
- * 2) no way to tell if agm packet was for finger 3
- * before 3->2, or finger 2 after 3->2.
- *
- * So, report 2 fingers, but empty all slots.
- * We will guess slots [0,1] on subsequent 2->2.
- */
- synaptics_mt_state_set(mt_state, 2, -1, -1);
- priv->mt_state_lost = true;
- break;
- case 4:
- case 5:
- /* mt_state was updated by AGM-CONTACT packet */
- break;
- }
-}
-
-/* Handle case where mt_state->count = 3 */
-static void synaptics_image_sensor_3f(struct synaptics_data *priv,
- struct synaptics_mt_state *mt_state)
-{
- struct synaptics_mt_state *old = &priv->mt_state;
-
- switch (old->count) {
- case 0:
- synaptics_mt_state_set(mt_state, 3, 0, 2);
- break;
- case 1:
- /*
- * If previous SGM contained slot 2 or higher, SGM now contains
- * slot 0 (one of the newly touching fingers) and AGM contains
- * SGM's previous slot.
- *
- * Otherwise, SGM now contains slot 0 and AGM contains slot 2.
- */
- if (old->sgm >= 2)
- synaptics_mt_state_set(mt_state, 3, 0, old->sgm);
- else
- synaptics_mt_state_set(mt_state, 3, 0, 2);
- break;
- case 2:
- /*
- * If the AGM previously contained slot 3 or higher, then the
- * newly touching finger is in the lowest available slot.
- *
- * If SGM was previously 1 or higher, then the new SGM is
- * now slot 0 (with a new finger), otherwise, the new finger
- * is now in a hidden slot between 0 and AGM's slot.
- *
- * In all such cases, the SGM now contains slot 0, and the AGM
- * continues to contain the same slot as before.
- */
- if (old->agm >= 3) {
- synaptics_mt_state_set(mt_state, 3, 0, old->agm);
- break;
- }
-
- /*
- * After some 3->1 and all 3->2 transitions, we lose track
- * of which slot is reported by SGM and AGM.
- *
- * For 2->3 in this state, report 3 fingers, but empty all
- * slots, and we will guess (0,2) on a subsequent 0->3.
- *
- * To userspace, the resulting transition will look like:
- * 2:[0,1] -> 3:[-1,-1] -> 3:[0,2]
- */
- if (priv->mt_state_lost) {
- synaptics_mt_state_set(mt_state, 3, -1, -1);
- break;
- }
-
- /*
- * If the (SGM,AGM) really previously contained slots (0, 1),
- * then we cannot know what slot was just reported by the AGM,
- * because the 2->3 transition can occur either before or after
- * the AGM packet. Thus, this most recent AGM could contain
- * either the same old slot 1 or the new slot 2.
- * Subsequent AGMs will be reporting slot 2.
- *
- * To userspace, the resulting transition will look like:
- * 2:[0,1] -> 3:[0,-1] -> 3:[0,2]
- */
- synaptics_mt_state_set(mt_state, 3, 0, -1);
- break;
- case 3:
- /*
- * If, for whatever reason, the previous agm was invalid,
- * Assume SGM now contains slot 0, AGM now contains slot 2.
- */
- if (old->agm <= 2)
- synaptics_mt_state_set(mt_state, 3, 0, 2);
- /*
- * mt_state either hasn't changed, or was updated by a recently
- * received AGM-CONTACT packet.
- */
- break;
-
- case 4:
- case 5:
- /* mt_state was updated by AGM-CONTACT packet */
- break;
- }
-}
-
-/* Handle case where mt_state->count = 4, or = 5 */
-static void synaptics_image_sensor_45f(struct synaptics_data *priv,
- struct synaptics_mt_state *mt_state)
-{
- /* mt_state was updated correctly by AGM-CONTACT packet */
- priv->mt_state_lost = false;
-}
-