Hi Chase,

Thanks for all of your reviews!

On Sat, Jul 23, 2011 at 9:02 AM, Chase Douglas
[off-list ref] wrote:

On 07/20/2011 06:39 AM, djkurtz@chromium.org wrote:

quoted

From: Daniel Kurtz <redacted>

Synaptics image sensor touchpads track up to 5 fingers, but only report 2.
They use a special "TYPE=2" (AGM-CONTACT) packet type that reports
the number of tracked fingers and which finger is reported in the SGM
and AGM packets.

With this new packet type, it is possible to tell userspace when 4 or 5
fingers are touching.

Maybe I'm blind, but I don't see where the QUADTAP and QUINTAP values
are set in the events. I see where the bits are set during
initialization, but not during use.

It's subtle.
The firmware actually report 4/5 in the AGM-CONTACT packet, which the
agm packet parser sets directly in mt_state->count.
This is then reported to userspace when synaptics_report_mt() calls
input_mt_report_finger_count(dev, mt_state->count), which now supports
QUINTTAP (see patch #8).

-Daniel

quoted

Signed-off-by: Daniel Kurtz <redacted>
---
 drivers/input/mouse/synaptics.c |   44 ++++++++++++++++++++++++++++++++++++++-
 1 files changed, 43 insertions(+), 1 deletions(-)

diff --git a/drivers/input/mouse/synaptics.c b/drivers/input/mouse/synaptics.c
index 893e567..2a1e05f 100644
--- a/drivers/input/mouse/synaptics.c
+++ b/drivers/input/mouse/synaptics.c

@@ -729,6 +729,10 @@ static void synaptics_image_sensor_1f(struct synaptics_data *priv,

              synaptics_mt_state_set(mt_state, 0, -1, -1);
              priv->mt_state_lost = true;
              break;
+     case 4:
+     case 5:
+             /* mt_state was updated by AGM-CONTACT packet */
+             break;
      }
 }

@@ -775,6 +779,10 @@ static void synaptics_image_sensor_2f(struct synaptics_data *priv,

              synaptics_mt_state_set(mt_state, 0, -1, -1);
              priv->mt_state_lost = true;
              break;
+     case 4:
+     case 5:
+             /* mt_state was updated by AGM-CONTACT packet */
+             break;
      }
 }

@@ -803,6 +811,22 @@ static void synaptics_image_sensor_3f(struct synaptics_data *priv,

              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.
               *

@@ -836,9 +860,22 @@ static void synaptics_image_sensor_3f(struct synaptics_data *priv,

               * 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;
+}
+
 static void synaptics_image_sensor_process(struct psmouse *psmouse,
                                         struct synaptics_hw_state *sgm)
 {

@@ -858,8 +895,10 @@ static void synaptics_image_sensor_process(struct psmouse *psmouse,

              synaptics_image_sensor_1f(priv, &mt_state);
      else if (sgm->w == 0)
              synaptics_image_sensor_2f(priv, &mt_state);
-     else if (sgm->w == 1)
+     else if (sgm->w == 1 && mt_state.count <= 3)
              synaptics_image_sensor_3f(priv, &mt_state);
+     else
+             synaptics_image_sensor_45f(priv, &mt_state);

      /* Send resulting input events to user space */
      synaptics_report_mt(psmouse, &mt_state, sgm);

@@ -1078,6 +1117,9 @@ static void set_input_params(struct input_dev *dev, struct synaptics_data *priv)

              input_set_abs_params(dev, ABS_MT_PRESSURE, 0, 255, 0, 0);
              /* Image sensors can sometimes report per-contact width */
              input_set_abs_params(dev, ABS_MT_TOUCH_MAJOR, 4, 15, 0, 0);
+             /* Image sensors can signal 4 and 5 finger clicks */
+             __set_bit(BTN_TOOL_QUADTAP, dev->keybit);
+             __set_bit(BTN_TOOL_QUINTTAP, dev->keybit);
      } else if (SYN_CAP_ADV_GESTURE(priv->ext_cap_0c)) {
              /* Non-image sensors with AGM use semi-mt */
              __set_bit(INPUT_PROP_SEMI_MT, dev->propbit);