Merge tag 'backport/v3.14.24-ltsi-rc1/phy-rcar-gen2-usb-to-v3.15' into backport/v3...

[platform/adaptation/renesas_rcar/renesas_kernel.git] / drivers / input / mouse / alps.c

diff --git a/drivers/input/mouse/alps.c b/drivers/input/mouse/alps.c
index fb15c64..4979b00 100644 (file)
--- a/drivers/input/mouse/alps.c
+++ b/drivers/input/mouse/alps.c
@@ -1047,7 +1047,13 @@ static psmouse_ret_t alps_process_byte(struct psmouse *psmouse)
 {
        struct alps_data *priv = psmouse->private;
 
-       if ((psmouse->packet[0] & 0xc8) == 0x08) { /* PS/2 packet */
+       /*
+        * Check if we are dealing with a bare PS/2 packet, presumably from
+        * a device connected to the external PS/2 port. Because bare PS/2
+        * protocol does not have enough constant bits to self-synchronize
+        * properly we only do this if the device is fully synchronized.
+        */
+       if (!psmouse->out_of_sync_cnt && (psmouse->packet[0] & 0xc8) == 0x08) {
                if (psmouse->pktcnt == 3) {
                        alps_report_bare_ps2_packet(psmouse, psmouse->packet,
                                                    true);
@@ -1071,12 +1077,27 @@ static psmouse_ret_t alps_process_byte(struct psmouse *psmouse)
        }
 
        /* Bytes 2 - pktsize should have 0 in the highest bit */
-       if ((priv->proto_version < ALPS_PROTO_V5) &&
+       if (priv->proto_version < ALPS_PROTO_V5 &&
            psmouse->pktcnt >= 2 && psmouse->pktcnt <= psmouse->pktsize &&
            (psmouse->packet[psmouse->pktcnt - 1] & 0x80)) {
                psmouse_dbg(psmouse, "refusing packet[%i] = %x\n",
                            psmouse->pktcnt - 1,
                            psmouse->packet[psmouse->pktcnt - 1]);
+
+               if (priv->proto_version == ALPS_PROTO_V3 &&
+                   psmouse->pktcnt == psmouse->pktsize) {
+                       /*
+                        * Some Dell boxes, such as Latitude E6440 or E7440
+                        * with closed lid, quite often smash last byte of
+                        * otherwise valid packet with 0xff. Given that the
+                        * next packet is very likely to be valid let's
+                        * report PSMOUSE_FULL_PACKET but not process data,
+                        * rather than reporting PSMOUSE_BAD_DATA and
+                        * filling the logs.
+                        */
+                       return PSMOUSE_FULL_PACKET;
+               }
+
                return PSMOUSE_BAD_DATA;
        }
 
@@ -2148,6 +2169,9 @@ int alps_init(struct psmouse *psmouse)
        /* We are having trouble resyncing ALPS touchpads so disable it for now */
        psmouse->resync_time = 0;
 
+       /* Allow 2 invalid packets without resetting device */
+       psmouse->resetafter = psmouse->pktsize * 2;
+
        return 0;
 
 init_fail: