Use a working magic sequence to configure absolute mode for elantech v2.

The synaptics driver now attaches to elantech v2 touchpads. It seems these
pads were always falling back to compat mode, which went unnoticed until r1.47.

Fix based on a patch submitted by Cedric Tessier:
http://marc.info/?l=openbsd-bugs&m=136904396518528&w=2
which in turn was probably based on parts of this patch:
https://launchpadlibrarian.net/73099683/elantech.patch
which updates the Linux driver code but isn't part of Torvald's Linux.

Behaviour of elantech firmware versions seems to vary quite a bit so print
the firmware version at attach time for reference in future bug reports.

Fix tested by frantisek holop and Peter J. Philipp.
ok mpi@

1 files changed, 17 insertions, 13 deletions

diff --git a/sys/dev/pckbc/pms.c b/sys/dev/pckbc/pms.c
index 4a995c92541..e68bcaddfc9 100644
--- a/sys/dev/pckbc/pms.c
+++ b/sys/dev/pckbc/pms.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: pms.c,v 1.47 2013/09/03 09:29:35 stsp Exp $ */
+/* $OpenBSD: pms.c,v 1.48 2013/09/20 14:07:30 stsp Exp $ */
 /* $NetBSD: psm.c,v 1.11 2000/06/05 22:20:57 sommerfeld Exp $ */
 
 /*-
@@ -118,6 +118,7 @@ struct elantech_softc {
 #define ELANTECH_F_HAS_ROCKER		0x02
 #define ELANTECH_F_2FINGER_PACKET	0x04
 #define ELANTECH_F_HW_V1_OLD		0x08
+	int fw_version;
 
 	int min_x, min_y;
 	int max_x, max_y;
@@ -1533,6 +1534,7 @@ elantech_set_absolute_mode_v2(struct pms_softc *sc)
 {
 	int i;
 	u_char resp[3];
+	u_char reg10 = (sc->elantech->fw_version == 0x20030 ? 0x54 : 0xc4);
 
 	/* Enable absolute mode. Magic numbers from Linux driver. */
 	if (elantech_ps2_cmd(sc, ELANTECH_PS2_CUSTOM_COMMAND) ||
@@ -1540,7 +1542,7 @@ elantech_set_absolute_mode_v2(struct pms_softc *sc)
 	    elantech_ps2_cmd(sc, ELANTECH_PS2_CUSTOM_COMMAND) ||
 	    elantech_ps2_cmd(sc, 0x10) ||
 	    elantech_ps2_cmd(sc, ELANTECH_PS2_CUSTOM_COMMAND) ||
-	    elantech_ps2_cmd(sc, 0x54) ||
+	    elantech_ps2_cmd(sc, reg10) ||
 	    pms_set_scaling(sc, 1) ||
 	    elantech_ps2_cmd(sc, ELANTECH_PS2_CUSTOM_COMMAND) ||
 	    elantech_ps2_cmd(sc, ELANTECH_CMD_WRITE_REG) ||
@@ -1548,13 +1550,6 @@ elantech_set_absolute_mode_v2(struct pms_softc *sc)
 	    elantech_ps2_cmd(sc, 0x11) ||
 	    elantech_ps2_cmd(sc, ELANTECH_PS2_CUSTOM_COMMAND) ||
 	    elantech_ps2_cmd(sc, 0x88) ||
-	    pms_set_scaling(sc, 1) ||
-	    elantech_ps2_cmd(sc, ELANTECH_PS2_CUSTOM_COMMAND) ||
-	    elantech_ps2_cmd(sc, ELANTECH_CMD_WRITE_REG) ||
-	    elantech_ps2_cmd(sc, ELANTECH_PS2_CUSTOM_COMMAND) ||
-	    elantech_ps2_cmd(sc, 0x21) ||
-	    elantech_ps2_cmd(sc, ELANTECH_PS2_CUSTOM_COMMAND) ||
-	    elantech_ps2_cmd(sc, 0x88) ||
 	    pms_set_scaling(sc, 1))
 		return (-1);
 
@@ -1642,6 +1637,8 @@ elantech_get_hwinfo_v1(struct pms_softc *sc)
 	} else
 		return (-1);
 
+	elantech->fw_version = fw_version;
+
 	if (pms_spec_cmd(sc, ELANTECH_QUE_CAPABILITIES) ||
 	    pms_get_status(sc, capabilities))
 		return (-1);
@@ -1676,6 +1673,7 @@ elantech_get_hwinfo_v2(struct pms_softc *sc)
 	if (ic_ver != 2 && ic_ver != 4)
 		return (-1);
 
+	elantech->fw_version = fw_version;
 	if (fw_version >= 0x20800)
 		elantech->flags |= ELANTECH_F_REPORTS_PRESSURE;
 
@@ -1730,6 +1728,7 @@ elantech_get_hwinfo_v3(struct pms_softc *sc)
 	if (((fw_version & 0x0f0000) >> 16) != 5)
 		return (-1);
 
+	elantech->fw_version = fw_version;
 	elantech->flags |= ELANTECH_F_REPORTS_PRESSURE;
 
 	if (elantech_set_absolute_mode_v3(sc))
@@ -1759,6 +1758,7 @@ elantech_get_hwinfo_v4(struct pms_softc *sc)
 	if (((fw_version & 0x0f0000) >> 16) != 6)
 		return (-1);
 
+	elantech->fw_version = fw_version;
 	elantech->flags |= ELANTECH_F_REPORTS_PRESSURE;
 
 	if (elantech_set_absolute_mode_v4(sc))
@@ -1835,7 +1835,8 @@ pms_enable_elantech_v1(struct pms_softc *sc)
 			goto err;
 		}
 
-		printf("%s: Elantech Touchpad, version %d\n", DEVNAME(sc), 1);
+		printf("%s: Elantech Touchpad, version %d, firmware 0x%x\n",
+		    DEVNAME(sc), 1, sc->elantech->fw_version);
 	} else if (elantech_set_absolute_mode_v1(sc))
 		goto err;
 
@@ -1873,7 +1874,8 @@ pms_enable_elantech_v2(struct pms_softc *sc)
 			goto err;
 		}
 
-		printf("%s: Elantech Touchpad, version %d\n", DEVNAME(sc), 2);
+		printf("%s: Elantech Touchpad, version %d, firmware 0x%x\n",
+		    DEVNAME(sc), 2, sc->elantech->fw_version);
 	} else if (elantech_set_absolute_mode_v2(sc))
 		goto err;
 
@@ -1908,7 +1910,8 @@ pms_enable_elantech_v3(struct pms_softc *sc)
 			goto err;
 		}
 
-		printf("%s: Elantech Touchpad, version %d\n", DEVNAME(sc), 3);
+		printf("%s: Elantech Touchpad, version %d, firmware 0x%x\n",
+		    DEVNAME(sc), 3, sc->elantech->fw_version);
 	} else if (elantech_set_absolute_mode_v3(sc))
 		goto err;
 
@@ -1943,7 +1946,8 @@ pms_enable_elantech_v4(struct pms_softc *sc)
 			goto err;
 		}
 
-		printf("%s: Elantech Clickpad, version %d\n", DEVNAME(sc), 4);
+		printf("%s: Elantech Clickpad, version %d, firmware 0x%x\n",
+		    DEVNAME(sc), 4, sc->elantech->fw_version);
 	} else if (elantech_set_absolute_mode_v4(sc))
 		goto err;