Input: wacom - add a quirk for low resolution Bamboo devices

The Bamboo Touch reports a sub-screen resolution of 480x320.  The
signal-to-noise ratio is only about 100, so filtering is needed in
order to reduce the jitter to a usable level. However, the low
resolution leads to round-off errors in the EWMA filter, resulting in
extremely jerky pointer motion. This patch explicitly sets a higher
resolution for those devices, and tells this to the completion handler
via a low-resolution quirk.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Acked-by: Ping Cheng <pingc@wacom.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
This commit is contained in:
Henrik Rydberg 2010-09-05 12:57:13 -07:00 committed by Dmitry Torokhov
parent cb734c0368
commit f4ccbef288
2 changed files with 11 additions and 0 deletions

View File

@ -857,6 +857,7 @@ static int wacom_tpc_irq(struct wacom_wac *wacom, size_t len)
static int wacom_bpt_irq(struct wacom_wac *wacom, size_t len)
{
struct wacom_features *features = &wacom->features;
struct input_dev *input = wacom->input;
unsigned char *data = wacom->data;
int sp = 0, sx = 0, sy = 0, count = 0;
@ -871,6 +872,10 @@ static int wacom_bpt_irq(struct wacom_wac *wacom, size_t len)
if (p) {
int x = get_unaligned_be16(&data[9 * i + 3]) & 0x7ff;
int y = get_unaligned_be16(&data[9 * i + 5]) & 0x7ff;
if (features->quirks & WACOM_QUIRK_BBTOUCH_LOWRES) {
x <<= 5;
y <<= 5;
}
input_report_abs(input, ABS_MT_PRESSURE, p);
input_report_abs(input, ABS_MT_POSITION_X, x);
input_report_abs(input, ABS_MT_POSITION_Y, y);
@ -1010,8 +1015,13 @@ void wacom_setup_device_quirks(struct wacom_features *features)
/* quirks for bamboo touch */
if (features->type == BAMBOO_PT &&
features->device_type == BTN_TOOL_TRIPLETAP) {
features->x_max <<= 5;
features->y_max <<= 5;
features->x_fuzz <<= 5;
features->y_fuzz <<= 5;
features->pressure_max = 256;
features->pressure_fuzz = 16;
features->quirks |= WACOM_QUIRK_BBTOUCH_LOWRES;
}
}

View File

@ -40,6 +40,7 @@
/* device quirks */
#define WACOM_QUIRK_MULTI_INPUT 0x0001
#define WACOM_QUIRK_BBTOUCH_LOWRES 0x0002
/* largest reported tracking id */
#define MAX_TRACKING_ID 0xfff