Some Synaptics touchpads have a middle mouse button that also works as
a scroll wheel. Scroll data is reported as packets with w == 2 and
the scroll amount in byte 1, treated as a signed character. For some
reason, the smallest possible wheel movement is reported as a scroll
amount of 4 units. This amount is typically spread out over more than
one packet, so the driver has to accumulate scroll delta values to
correctly deal with this.
Signed-off-by: Peter Osterlund <[EMAIL PROTECTED]>
---
linux-petero/drivers/input/mouse/synaptics.c | 28 +++++++++++++++++++++++++--
linux-petero/drivers/input/mouse/synaptics.h | 2 +
2 files changed, 28 insertions(+), 2 deletions(-)
diff -puN drivers/input/mouse/synaptics.c~synaptics-scroll-wheel
drivers/input/mouse/synaptics.c
--- linux/drivers/input/mouse/synaptics.c~synaptics-scroll-wheel
2005-01-30 11:22:34.000000000 +0100
+++ linux-petero/drivers/input/mouse/synaptics.c 2005-01-30
11:22:34.000000000 +0100
@@ -322,8 +322,11 @@ static void synaptics_parse_hw_state(uns
hw->left = (buf[0] & 0x01) ? 1 : 0;
hw->right = (buf[0] & 0x02) ? 1 : 0;
- if (SYN_CAP_MIDDLE_BUTTON(priv->capabilities))
+ if (SYN_CAP_MIDDLE_BUTTON(priv->capabilities)) {
hw->middle = ((buf[0] ^ buf[3]) & 0x01) ? 1 : 0;
+ if (hw->w == 2)
+ hw->scroll = (signed char)(buf[1]);
+ }
if (SYN_CAP_FOUR_BUTTON(priv->capabilities)) {
hw->up = ((buf[0] ^ buf[3]) & 0x01) ? 1 : 0;
@@ -379,6 +382,26 @@ static void synaptics_process_packet(str
synaptics_parse_hw_state(psmouse->packet, priv, &hw);
+ if (hw.scroll) {
+ priv->scroll += hw.scroll;
+
+ while (priv->scroll >= 4) {
+ input_report_key(dev, BTN_BACK, !hw.down);
+ input_sync(dev);
+ input_report_key(dev, BTN_BACK, hw.down);
+ input_sync(dev);
+ priv->scroll -= 4;
+ }
+ while (priv->scroll <= -4) {
+ input_report_key(dev, BTN_FORWARD, !hw.up);
+ input_sync(dev);
+ input_report_key(dev, BTN_FORWARD, hw.up);
+ input_sync(dev);
+ priv->scroll += 4;
+ }
+ return;
+ }
+
if (hw.z > 0) {
num_fingers = 1;
finger_width = 5;
@@ -528,7 +551,8 @@ static void set_input_params(struct inpu
if (SYN_CAP_MIDDLE_BUTTON(priv->capabilities))
set_bit(BTN_MIDDLE, dev->keybit);
- if (SYN_CAP_FOUR_BUTTON(priv->capabilities)) {
+ if (SYN_CAP_FOUR_BUTTON(priv->capabilities) ||
+ SYN_CAP_MIDDLE_BUTTON(priv->capabilities)) {
set_bit(BTN_FORWARD, dev->keybit);
set_bit(BTN_BACK, dev->keybit);
}
diff -puN drivers/input/mouse/synaptics.h~synaptics-scroll-wheel
drivers/input/mouse/synaptics.h
--- linux/drivers/input/mouse/synaptics.h~synaptics-scroll-wheel
2005-01-30 11:22:34.000000000 +0100
+++ linux-petero/drivers/input/mouse/synaptics.h 2005-01-30
11:22:34.000000000 +0100
@@ -92,6 +92,7 @@ struct synaptics_hw_state {
unsigned int up:1;
unsigned int down:1;
unsigned char ext_buttons;
+ signed char scroll;
};
struct synaptics_data {
@@ -103,6 +104,7 @@ struct synaptics_data {
unsigned char pkt_type; /* packet type - old, new, etc
*/
unsigned char mode; /* current mode byte */
+ int scroll;
};
#endif /* _SYNAPTICS_H */
_
--
Peter Osterlund - [EMAIL PROTECTED]
http://web.telia.com/~u89404340
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
