diff options
Diffstat (limited to 'drivers/input')
| -rw-r--r-- | drivers/input/mouse/alps.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/input/mouse/alps.c b/drivers/input/mouse/alps.c index 8996323ce8d9..62ffea00902a 100644 --- a/drivers/input/mouse/alps.c +++ b/drivers/input/mouse/alps.c @@ -21,6 +21,7 @@ #include "psmouse.h" #include "alps.h" +#include "trackpoint.h" /* * Definitions for ALPS version 3 and 4 command mode protocol @@ -2861,6 +2862,23 @@ static const struct alps_protocol_info *alps_match_table(unsigned char *e7, return NULL; } +static bool alps_is_cs19_trackpoint(struct psmouse *psmouse) +{ + u8 param[2] = { 0 }; + + if (ps2_command(&psmouse->ps2dev, + param, MAKE_PS2_CMD(0, 2, TP_READ_ID))) + return false; + + /* + * param[0] contains the trackpoint device variant_id while + * param[1] contains the firmware_id. So far all alps + * trackpoint-only devices have their variant_ids equal + * TP_VARIANT_ALPS and their firmware_ids are in 0x20~0x2f range. + */ + return param[0] == TP_VARIANT_ALPS && (param[1] & 0x20); +} + static int alps_identify(struct psmouse *psmouse, struct alps_data *priv) { const struct alps_protocol_info *protocol; @@ -3162,6 +3180,20 @@ int alps_detect(struct psmouse *psmouse, bool set_properties) return error; /* + * ALPS cs19 is a trackpoint-only device, and uses different + * protocol than DualPoint ones, so we return -EINVAL here and let + * trackpoint.c drive this device. If the trackpoint driver is not + * enabled, the device will fall back to a bare PS/2 mouse. + * If ps2_command() fails here, we depend on the immediately + * followed psmouse_reset() to reset the device to normal state. + */ + if (alps_is_cs19_trackpoint(psmouse)) { + psmouse_dbg(psmouse, + "ALPS CS19 trackpoint-only device detected, ignoring\n"); + return -EINVAL; + } + + /* * Reset the device to make sure it is fully operational: * on some laptops, like certain Dell Latitudes, we may * fail to properly detect presence of trackstick if device |