diff options
| author | JJ Ding <jj_ding@emc.com.tw> | 2011-09-09 21:28:04 +0400 |
|---|---|---|
| committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2011-09-09 21:34:50 +0400 |
| commit | 7894f21b109848130be7547448af89dc33d0f268 (patch) | |
| tree | 430abd74d0ffc9006fd2bdf350418482378fe043 /drivers/input/mouse/elantech.c | |
| parent | 8a360d09b14514139b883d970cd3a1b0b63e6717 (diff) | |
| download | linux-7894f21b109848130be7547448af89dc33d0f268.tar.xz | |
Input: elantech - packet checking for v2 hardware
For v2 hardware, there is no real parity check, but we can still check
some constant bits for data integrity.
Also rename elantech_check_parity_v1 to elantech_packet_check_v1 to make
these packet checking function names consistent.
Signed-off-by: JJ Ding <jj_ding@emc.com.tw>
Acked-by: Daniel Kurtz <djkurtz@chromium.org>
Acked-by: Éric Piel <eric.piel@tremplin-utc.net>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Diffstat (limited to 'drivers/input/mouse/elantech.c')
| -rw-r--r-- | drivers/input/mouse/elantech.c | 39 |
1 files changed, 34 insertions, 5 deletions
diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c index 296b6a6250fd..f2e3a2be041c 100644 --- a/drivers/input/mouse/elantech.c +++ b/drivers/input/mouse/elantech.c @@ -350,7 +350,7 @@ static void elantech_report_absolute_v2(struct psmouse *psmouse) input_sync(dev); } -static int elantech_check_parity_v1(struct psmouse *psmouse) +static int elantech_packet_check_v1(struct psmouse *psmouse) { struct elantech_data *etd = psmouse->private; unsigned char *packet = psmouse->packet; @@ -374,6 +374,34 @@ static int elantech_check_parity_v1(struct psmouse *psmouse) etd->parity[packet[3]] == p3; } +static int elantech_packet_check_v2(struct psmouse *psmouse) +{ + struct elantech_data *etd = psmouse->private; + unsigned char *packet = psmouse->packet; + + /* + * V2 hardware has two flavors. Older ones that do not report pressure, + * and newer ones that reports pressure and width. With newer ones, all + * packets (1, 2, 3 finger touch) have the same constant bits. With + * older ones, 1/3 finger touch packets and 2 finger touch packets + * have different constant bits. + * With all three cases, if the constant bits are not exactly what I + * expected, I consider them invalid. + */ + if (etd->reports_pressure) + return (packet[0] & 0x0c) == 0x04 && + (packet[3] & 0x0f) == 0x02; + + if ((packet[0] & 0xc0) == 0x80) + return (packet[0] & 0x0c) == 0x0c && + (packet[3] & 0x0e) == 0x08; + + return (packet[0] & 0x3c) == 0x3c && + (packet[1] & 0xf0) == 0x00 && + (packet[3] & 0x3e) == 0x38 && + (packet[4] & 0xf0) == 0x00; +} + /* * Process byte stream from mouse and handle complete packets */ @@ -389,14 +417,16 @@ static psmouse_ret_t elantech_process_byte(struct psmouse *psmouse) switch (etd->hw_version) { case 1: - if (etd->paritycheck && !elantech_check_parity_v1(psmouse)) + if (etd->paritycheck && !elantech_packet_check_v1(psmouse)) return PSMOUSE_BAD_DATA; elantech_report_absolute_v1(psmouse); break; case 2: - /* We don't know how to check parity in protocol v2 */ + if (etd->paritycheck && !elantech_packet_check_v2(psmouse)) + return PSMOUSE_BAD_DATA; + elantech_report_absolute_v2(psmouse); break; } @@ -795,8 +825,7 @@ int elantech_init(struct psmouse *psmouse) etd->hw_version = 2; /* For now show extra debug information */ etd->debug = 1; - /* Don't know how to do parity checking for version 2 */ - etd->paritycheck = 0; + etd->paritycheck = 1; if (etd->fw_version >= 0x020800) etd->reports_pressure = true; |