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Input: ALPS - add semi-MT support for v3 protocol
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Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Acked-by: Chase Douglas <chase.douglas@canonical.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
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Seth Forshee authored and Dmitry Torokhov committed Nov 8, 2011
1 parent 25bded7 commit 01ce661
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Showing 2 changed files with 215 additions and 19 deletions.
233 changes: 214 additions & 19 deletions drivers/input/mouse/alps.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,7 @@

#include <linux/slab.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/serio.h>
#include <linux/libps2.h>

Expand All @@ -26,6 +27,12 @@
/*
* Definitions for ALPS version 3 and 4 command mode protocol
*/
#define ALPS_V3_X_MAX 2000
#define ALPS_V3_Y_MAX 1400

#define ALPS_BITMAP_X_BITS 15
#define ALPS_BITMAP_Y_BITS 11

#define ALPS_CMD_NIBBLE_10 0x01f2

static const struct alps_nibble_commands alps_v3_nibble_commands[] = {
Expand Down Expand Up @@ -250,6 +257,137 @@ static void alps_process_packet_v1_v2(struct psmouse *psmouse)
input_sync(dev);
}

/*
* Process bitmap data from v3 and v4 protocols. Returns the number of
* fingers detected. A return value of 0 means at least one of the
* bitmaps was empty.
*
* The bitmaps don't have enough data to track fingers, so this function
* only generates points representing a bounding box of all contacts.
* These points are returned in x1, y1, x2, and y2 when the return value
* is greater than 0.
*/
static int alps_process_bitmap(unsigned int x_map, unsigned int y_map,
int *x1, int *y1, int *x2, int *y2)
{
struct alps_bitmap_point {
int start_bit;
int num_bits;
};

int fingers_x = 0, fingers_y = 0, fingers;
int i, bit, prev_bit;
struct alps_bitmap_point x_low = {0,}, x_high = {0,};
struct alps_bitmap_point y_low = {0,}, y_high = {0,};
struct alps_bitmap_point *point;

if (!x_map || !y_map)
return 0;

*x1 = *y1 = *x2 = *y2 = 0;

prev_bit = 0;
point = &x_low;
for (i = 0; x_map != 0; i++, x_map >>= 1) {
bit = x_map & 1;
if (bit) {
if (!prev_bit) {
point->start_bit = i;
fingers_x++;
}
point->num_bits++;
} else {
if (prev_bit)
point = &x_high;
else
point->num_bits = 0;
}
prev_bit = bit;
}

/*
* y bitmap is reversed for what we need (lower positions are in
* higher bits), so we process from the top end.
*/
y_map = y_map << (sizeof(y_map) * BITS_PER_BYTE - ALPS_BITMAP_Y_BITS);
prev_bit = 0;
point = &y_low;
for (i = 0; y_map != 0; i++, y_map <<= 1) {
bit = y_map & (1 << (sizeof(y_map) * BITS_PER_BYTE - 1));
if (bit) {
if (!prev_bit) {
point->start_bit = i;
fingers_y++;
}
point->num_bits++;
} else {
if (prev_bit)
point = &y_high;
else
point->num_bits = 0;
}
prev_bit = bit;
}

/*
* Fingers can overlap, so we use the maximum count of fingers
* on either axis as the finger count.
*/
fingers = max(fingers_x, fingers_y);

/*
* If total fingers is > 1 but either axis reports only a single
* contact, we have overlapping or adjacent fingers. For the
* purposes of creating a bounding box, divide the single contact
* (roughly) equally between the two points.
*/
if (fingers > 1) {
if (fingers_x == 1) {
i = x_low.num_bits / 2;
x_low.num_bits = x_low.num_bits - i;
x_high.start_bit = x_low.start_bit + i;
x_high.num_bits = max(i, 1);
} else if (fingers_y == 1) {
i = y_low.num_bits / 2;
y_low.num_bits = y_low.num_bits - i;
y_high.start_bit = y_low.start_bit + i;
y_high.num_bits = max(i, 1);
}
}

*x1 = (ALPS_V3_X_MAX * (2 * x_low.start_bit + x_low.num_bits - 1)) /
(2 * (ALPS_BITMAP_X_BITS - 1));
*y1 = (ALPS_V3_Y_MAX * (2 * y_low.start_bit + y_low.num_bits - 1)) /
(2 * (ALPS_BITMAP_Y_BITS - 1));

if (fingers > 1) {
*x2 = (ALPS_V3_X_MAX * (2 * x_high.start_bit + x_high.num_bits - 1)) /
(2 * (ALPS_BITMAP_X_BITS - 1));
*y2 = (ALPS_V3_Y_MAX * (2 * y_high.start_bit + y_high.num_bits - 1)) /
(2 * (ALPS_BITMAP_Y_BITS - 1));
}

return fingers;
}

static void alps_set_slot(struct input_dev *dev, int slot, bool active,
int x, int y)
{
input_mt_slot(dev, slot);
input_mt_report_slot_state(dev, MT_TOOL_FINGER, active);
if (active) {
input_report_abs(dev, ABS_MT_POSITION_X, x);
input_report_abs(dev, ABS_MT_POSITION_Y, y);
}
}

static void alps_report_semi_mt_data(struct input_dev *dev, int num_fingers,
int x1, int y1, int x2, int y2)
{
alps_set_slot(dev, 0, num_fingers != 0, x1, y1);
alps_set_slot(dev, 1, num_fingers == 2, x2, y2);
}

static void alps_process_trackstick_packet_v3(struct psmouse *psmouse)
{
struct alps_data *priv = psmouse->private;
Expand Down Expand Up @@ -318,35 +456,67 @@ static void alps_process_touchpad_packet_v3(struct psmouse *psmouse)
struct input_dev *dev2 = priv->dev2;
int x, y, z;
int left, right, middle;
int x1 = 0, y1 = 0, x2 = 0, y2 = 0;
int fingers = 0, bmap_fingers;
unsigned int x_bitmap, y_bitmap;

/*
* There's no single feature of touchpad position and bitmap
* packets that can be used to distinguish between them. We
* rely on the fact that a bitmap packet should always follow
* a position packet with bit 6 of packet[4] set.
* There's no single feature of touchpad position and bitmap packets
* that can be used to distinguish between them. We rely on the fact
* that a bitmap packet should always follow a position packet with
* bit 6 of packet[4] set.
*/
if (priv->multi_packet) {
priv->multi_packet = 0;

/*
* Sometimes a position packet will indicate a multi-packet
* sequence, but then what follows is another position
* packet. Check for this, and when it happens process the
* position packet as usual.
*/
if (packet[0] & 0x40) {
fingers = (packet[5] & 0x3) + 1;
x_bitmap = ((packet[4] & 0x7e) << 8) |
((packet[1] & 0x7f) << 2) |
((packet[0] & 0x30) >> 4);
y_bitmap = ((packet[3] & 0x70) << 4) |
((packet[2] & 0x7f) << 1) |
(packet[4] & 0x01);

bmap_fingers = alps_process_bitmap(x_bitmap, y_bitmap,
&x1, &y1, &x2, &y2);

/*
* Bitmap packets are not yet supported, so for now
* just ignore them.
* We shouldn't report more than one finger if
* we don't have two coordinates.
*/
return;
if (fingers > 1 && bmap_fingers < 2)
fingers = bmap_fingers;

/* Now process position packet */
packet = priv->multi_data;
} else {
priv->multi_packet = 0;
}
}

if (!priv->multi_packet && (packet[4] & 0x40))
/*
* Bit 6 of byte 0 is not usually set in position packets. The only
* times it seems to be set is in situations where the data is
* suspect anyway, e.g. a palm resting flat on the touchpad. Given
* this combined with the fact that this bit is useful for filtering
* out misidentified bitmap packets, we reject anything with this
* bit set.
*/
if (packet[0] & 0x40)
return;

if (!priv->multi_packet && (packet[4] & 0x40)) {
priv->multi_packet = 1;
else
priv->multi_packet = 0;
memcpy(priv->multi_data, packet, sizeof(priv->multi_data));
return;
}

priv->multi_packet = 0;

left = packet[3] & 0x01;
right = packet[3] & 0x02;
Expand All @@ -366,22 +536,38 @@ static void alps_process_touchpad_packet_v3(struct psmouse *psmouse)
if (x && y && !z)
return;

/*
* If we don't have MT data or the bitmaps were empty, we have
* to rely on ST data.
*/
if (!fingers) {
x1 = x;
y1 = y;
fingers = z > 0 ? 1 : 0;
}

if (z >= 64)
input_report_key(dev, BTN_TOUCH, 1);
else
input_report_key(dev, BTN_TOUCH, 0);

alps_report_semi_mt_data(dev, fingers, x1, y1, x2, y2);

input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
input_report_key(dev, BTN_TOOL_DOUBLETAP, fingers == 2);
input_report_key(dev, BTN_TOOL_TRIPLETAP, fingers == 3);
input_report_key(dev, BTN_TOOL_QUADTAP, fingers == 4);

input_report_key(dev, BTN_LEFT, left);
input_report_key(dev, BTN_RIGHT, right);
input_report_key(dev, BTN_MIDDLE, middle);

if (z > 0) {
input_report_abs(dev, ABS_X, x);
input_report_abs(dev, ABS_Y, y);
}
input_report_abs(dev, ABS_PRESSURE, z);

input_report_key(dev, BTN_TOOL_FINGER, z > 0);
input_report_key(dev, BTN_LEFT, left);
input_report_key(dev, BTN_RIGHT, right);
input_report_key(dev, BTN_MIDDLE, middle);

input_sync(dev);

if (!(priv->quirks & ALPS_QUIRK_TRACKSTICK_BUTTONS)) {
Expand Down Expand Up @@ -1368,9 +1554,18 @@ int alps_init(struct psmouse *psmouse)
input_set_abs_params(dev1, ABS_Y, 0, 767, 0, 0);
break;
case ALPS_PROTO_V3:
set_bit(INPUT_PROP_SEMI_MT, dev1->propbit);
input_mt_init_slots(dev1, 2);
input_set_abs_params(dev1, ABS_MT_POSITION_X, 0, ALPS_V3_X_MAX, 0, 0);
input_set_abs_params(dev1, ABS_MT_POSITION_Y, 0, ALPS_V3_Y_MAX, 0, 0);

set_bit(BTN_TOOL_DOUBLETAP, dev1->keybit);
set_bit(BTN_TOOL_TRIPLETAP, dev1->keybit);
set_bit(BTN_TOOL_QUADTAP, dev1->keybit);
/* fall through */
case ALPS_PROTO_V4:
input_set_abs_params(dev1, ABS_X, 0, 2000, 0, 0);
input_set_abs_params(dev1, ABS_Y, 0, 1400, 0, 0);
input_set_abs_params(dev1, ABS_X, 0, ALPS_V3_X_MAX, 0, 0);
input_set_abs_params(dev1, ABS_Y, 0, ALPS_V3_Y_MAX, 0, 0);
break;
}

Expand Down
1 change: 1 addition & 0 deletions drivers/input/mouse/alps.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -38,6 +38,7 @@ struct alps_data {
int addr_command; /* Command to set register address */
int prev_fin; /* Finger bit from previous packet */
int multi_packet; /* Multi-packet data in progress */
unsigned char multi_data[6]; /* Saved multi-packet data */
u8 quirks;
struct timer_list timer;
};
Expand Down

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