psmouse: added BYD touchpad driver

This adds proper single-touch support for BYD touchpads to the psmouse input driver.

This patch is against commit b82dde0230439215b55e545880e90337ee16f51a (Merge tag 'please-pull-copy_file_range' of
git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux ) of Linus' kernel branch.

drivers/input/mouse/byd.c new file +124 -0

+/* BYD commands reverse engineered from windows driver */
+
+/*
+ * swipe gesture from off-pad to on-pad
+ *  0 : disable
+ *  1 : enable
+ */
+#define BYD_CMD_SET_OFFSCREEN_SWIPE             0xcc
+/*
+ * tap and drag delay time
+ *  0 : disable
+ *  1 - 8 : least to most delay
+ */
+#define BYD_CMD_SET_TAP_DRAG_DELAY_TIME         0xcf
+/*
+ * physical buttons function mapping
+ *  0 : enable
+ *  4 : normal
+ *  5 : left button custom command
+ *  6 : right button custom command
+ *  8 : disable
+ */
+#define BYD_CMD_SET_PHYSICAL_BUTTONS            0xd0
+/*
+ * absolute mode (1 byte X/Y resolution)
+ *  0 : disable
+ *  2 : enable
+ */
+#define BYD_CMD_SET_ABSOLUTE_MODE               0xd1
+/*
+ * two finger scrolling
+ *  1 : vertical
+ *  2 : horizontal
+ *  3 : vertical + horizontal
+ *  4 : disable
+ */
+#define BYD_CMD_SET_TWO_FINGER_SCROLL           0xd2
+/*
+ * handedness
+ *  1 : right handed
+ *  2 : left handed
+ */
+#define BYD_CMD_SET_HANDEDNESS                  0xd3
+/*
+ * tap to click
+ *  1 : enable
+ *  2 : disable
+ */
+#define BYD_CMD_SET_TAP                         0xd4
+/*
+ * tap and drag
+ *  1 : tap and hold to drag
+ *  2 : tap and hold to drag + lock
+ *  3 : disable
+ */
+#define BYD_CMD_SET_TAP_DRAG                    0xd5
+/*
+ * touch sensitivity
+ *  1 - 7 : least to most sensitive
+ */
+#define BYD_CMD_SET_TOUCH_SENSITIVITY           0xd6
+/*
+ * one finger scrolling
+ *  1 : vertical
+ *  2 : horizontal
+ *  3 : vertical + horizontal
+ *  4 : disable
+ */
+#define BYD_CMD_SET_ONE_FINGER_SCROLL           0xd7
+/*
+ * one finger scrolling function
+ *  1 : free scrolling
+ *  2 : edge motion
+ *  3 : free scrolling + edge motion
+ *  4 : disable
+ */
+#define BYD_CMD_SET_ONE_FINGER_SCROLL_FUNC      0xd8
+/*
+ * sliding speed
+ *  1 - 5 : slowest to fastest
+ */
+#define BYD_CMD_SET_SLIDING_SPEED               0xda
+/*
+ * edge motion
+ *  1 : disable
+ *  2 : enable when dragging
+ *  3 : enable when dragging and pointing
+ */
+#define BYD_CMD_SET_EDGE_MOTION                 0xdb
+/*
+ * left edge region size
+ *  0 - 7 : smallest to largest width
+ */
+#define BYD_CMD_SET_LEFT_EDGE_REGION            0xdc
+/*
+ * top edge region size
+ *  0 - 9 : smallest to largest height
+ */
+#define BYD_CMD_SET_TOP_EDGE_REGION             0xdd
+/*
+ * disregard palm press as clicks
+ *  1 - 6 : smallest to largest
+ */
+#define BYD_CMD_SET_PALM_CHECK                  0xde
+/* right edge region size
+ *  0 - 7 : smallest to largest width
+ */
+#define BYD_CMD_SET_RIGHT_EDGE_REGION           0xdf
+/*
+ * bottom edge region size
+ *  0 - 9 : smallest to largest height
+ */
+#define BYD_CMD_SET_BOTTOM_EDGE_REGION          0xe1
+/*
+ * multitouch gestures
+ *  1 : enable
+ *  2 : disable
+ */
+#define BYD_CMD_SET_MULTITOUCH                  0xe3
+/*
+ * edge motion speed
+ *  0 : control with finger pressure
+ *  1 - 9 : slowest to fastest
+ */

drivers/input/mouse/byd.c new file +4 -0

+static void byd_report_input(struct psmouse *psmouse)
+{
+ struct byd_data *priv = (struct byd_data *)psmouse->private;
+ struct input_dev *dev = psmouse->dev;

drivers/input/mouse/byd.c new file +8 -0

+
+static void byd_clear_touch(unsigned long data)
+{
+ struct psmouse *psmouse = (struct psmouse *)data;
+ struct byd_data *priv = psmouse->private;
+
+ serio_pause_rx(psmouse->ps2dev.serio);
+

+ switch (packet[3]) {
+ case BYD_PKT_ABSOLUTE:
+ /* on first touch, use the absolute packet to determine our start location */
+ if (priv->touch == 0) {
+ priv->abs_x = packet[1] * (BYD_CONST_PAD_WIDTH / 256);
+ priv->abs_y = (255 - packet[2]) * (BYD_CONST_PAD_HEIGHT / 256);

drivers/input/mouse/byd.c new file +14 -0

+
+ /* needed to detect tap */
+ if (now_msecs - priv->last_touch_time > 64) {
+ priv->touch = 1;
+ }
+ }
+ break;
+ case BYD_PKT_RELATIVE:
+ {
+ int32_t rel_x, rel_y;
+
+ /* same as regular PS/2 psmouse protocoal */
+ rel_x = packet[1] ? (int) packet[1] - (int) ((packet[0] << 4) & 0x100) : 0;
+ rel_y = packet[2] ? (int) ((packet[0] << 3) & 0x100) - (int) packet[2] : 0;

Hi Richard,

Quoted 2 lines

This adds proper single-touch support for BYD touchpads to the psmouse input driver.

I posted a driver for the same touchpad a few weeks ago, which has been merged into linux-next. There's some stuff in this patch which is missing in my driver though, so we should definitely try and include that, and I'm very curious about the pseudo-absolute mode.

Quoted 4 lines

This patch is against commit b82dde0230439215b55e545880e90337ee16f51a (Merge tag 'please-pull-copy_file_range' of
git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux ) of Linus' kernel branch.

Can you rebase against 'git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input'?

Quoted 124 lines

drivers/input/mouse/byd.c new file +124 -0

+/* BYD commands reverse engineered from windows driver */
+
+/*
+ * swipe gesture from off-pad to on-pad
+ *  0 : disable
+ *  1 : enable
+ */
+#define BYD_CMD_SET_OFFSCREEN_SWIPE             0xcc
+/*
+ * tap and drag delay time
+ *  0 : disable
+ *  1 - 8 : least to most delay
+ */
+#define BYD_CMD_SET_TAP_DRAG_DELAY_TIME         0xcf
+/*
+ * physical buttons function mapping
+ *  0 : enable
+ *  4 : normal
+ *  5 : left button custom command
+ *  6 : right button custom command
+ *  8 : disable
+ */
+#define BYD_CMD_SET_PHYSICAL_BUTTONS            0xd0
+/*
+ * absolute mode (1 byte X/Y resolution)
+ *  0 : disable
+ *  2 : enable
+ */
+#define BYD_CMD_SET_ABSOLUTE_MODE               0xd1
+/*
+ * two finger scrolling
+ *  1 : vertical
+ *  2 : horizontal
+ *  3 : vertical + horizontal
+ *  4 : disable
+ */
+#define BYD_CMD_SET_TWO_FINGER_SCROLL           0xd2
+/*
+ * handedness
+ *  1 : right handed
+ *  2 : left handed
+ */
+#define BYD_CMD_SET_HANDEDNESS                  0xd3
+/*
+ * tap to click
+ *  1 : enable
+ *  2 : disable
+ */
+#define BYD_CMD_SET_TAP                         0xd4
+/*
+ * tap and drag
+ *  1 : tap and hold to drag
+ *  2 : tap and hold to drag + lock
+ *  3 : disable
+ */
+#define BYD_CMD_SET_TAP_DRAG                    0xd5
+/*
+ * touch sensitivity
+ *  1 - 7 : least to most sensitive
+ */
+#define BYD_CMD_SET_TOUCH_SENSITIVITY           0xd6
+/*
+ * one finger scrolling
+ *  1 : vertical
+ *  2 : horizontal
+ *  3 : vertical + horizontal
+ *  4 : disable
+ */
+#define BYD_CMD_SET_ONE_FINGER_SCROLL           0xd7
+/*
+ * one finger scrolling function
+ *  1 : free scrolling
+ *  2 : edge motion
+ *  3 : free scrolling + edge motion
+ *  4 : disable
+ */
+#define BYD_CMD_SET_ONE_FINGER_SCROLL_FUNC      0xd8
+/*
+ * sliding speed
+ *  1 - 5 : slowest to fastest
+ */
+#define BYD_CMD_SET_SLIDING_SPEED               0xda
+/*
+ * edge motion
+ *  1 : disable
+ *  2 : enable when dragging
+ *  3 : enable when dragging and pointing
+ */
+#define BYD_CMD_SET_EDGE_MOTION                 0xdb
+/*
+ * left edge region size
+ *  0 - 7 : smallest to largest width
+ */
+#define BYD_CMD_SET_LEFT_EDGE_REGION            0xdc
+/*
+ * top edge region size
+ *  0 - 9 : smallest to largest height
+ */
+#define BYD_CMD_SET_TOP_EDGE_REGION             0xdd
+/*
+ * disregard palm press as clicks
+ *  1 - 6 : smallest to largest
+ */
+#define BYD_CMD_SET_PALM_CHECK                  0xde
+/* right edge region size
+ *  0 - 7 : smallest to largest width
+ */
+#define BYD_CMD_SET_RIGHT_EDGE_REGION           0xdf
+/*
+ * bottom edge region size
+ *  0 - 9 : smallest to largest height
+ */
+#define BYD_CMD_SET_BOTTOM_EDGE_REGION          0xe1
+/*
+ * multitouch gestures
+ *  1 : enable
+ *  2 : disable
+ */
+#define BYD_CMD_SET_MULTITOUCH                  0xe3
+/*
+ * edge motion speed
+ *  0 : control with finger pressure
+ *  1 - 9 : slowest to fastest
+ */

drivers/input/mouse/byd.c line 184

Quoted 10 lines

drivers/input/mouse/byd.c new file +10 -0

+#define BYD_CMD_SET_EDGE_MOTION_SPEED           0xe4
+/*
+ * two finger scolling function
+ *  0 : free scrolling
+ *  1 : free scrolling (with momentum)
+ *  2 : edge motion
+ *  3 : free scrolling (with momentum) + edge motion
+ *  4 : disable
+ */
+#define BYD_CMD_SET_TWO_FINGER_SCROLL_FUNC      0xe5

These are definitely worth merging into the existing driver - I never got the time to figure out all of the different settings.

drivers/input/mouse/byd.c line 257

Quoted 11 lines

drivers/input/mouse/byd.c new file +11 -0

+
+struct byd_data {
+ struct timer_list timer;
+ int32_t abs_x;
+ int32_t abs_y;
+ uint32_t last_touch_time;
+ uint32_t button_left      : 1;
+ uint32_t button_right     : 1;
+ uint32_t touch            : 1;
+};
+

It looks like whatever email client you used has broken the formatting - when you resend, can you use something which will preserve whitespace properly? See 'Documentation/email-clients.txt'.

Quoted 4 lines

drivers/input/mouse/byd.c new file +4 -0

+static void byd_report_input(struct psmouse *psmouse)
+{
+ struct byd_data *priv = (struct byd_data *)psmouse->private;
+ struct input_dev *dev = psmouse->dev;

drivers/input/mouse/byd.c line 271

Quoted 10 lines

drivers/input/mouse/byd.c new file +10 -0

+
+ input_report_abs(dev, ABS_X, priv->abs_x);
+ input_report_abs(dev, ABS_Y, priv->abs_y);
+ input_report_key(dev, BTN_LEFT, priv->button_left);
+ input_report_key(dev, BTN_RIGHT, priv->button_right);
+ input_report_key(dev, BTN_TOUCH, priv->touch);
+ input_report_key(dev, BTN_TOOL_FINGER, priv->touch);
+
+ input_sync(dev);
+}

Could you explain generally why you're reporting in absolute mode? What advantage does it have over using relative reporting and turning off the absolute packets in the touchpad init sequence?

Quoted 8 lines

drivers/input/mouse/byd.c new file +8 -0

+
+static void byd_clear_touch(unsigned long data)
+{
+ struct psmouse *psmouse = (struct psmouse *)data;
+ struct byd_data *priv = psmouse->private;
+
+ serio_pause_rx(psmouse->ps2dev.serio);
+

drivers/input/mouse/byd.c line 289

Quoted 10 lines

drivers/input/mouse/byd.c new file +10 -0

+ priv->touch = 0;
+ /*
+ * move cursor back to center of pad when we lose touch
+ * this specifically improves user experiencce when moving
+ * cursor with one finger, and pressing butoton with other
+ */
+ priv->abs_x = BYD_CONST_PAD_WIDTH / 2;
+ priv->abs_y = BYD_CONST_PAD_HEIGHT / 2;
+
+ byd_report_input(psmouse);

serio_pause_rx() takes a spinlock - might be worth checking that byd_report_input() doesn't do anything that might sleep.

Quoted 20 lines

+ switch (packet[3]) {
+ case BYD_PKT_ABSOLUTE:
+ /* on first touch, use the absolute packet to determine our start location */
+ if (priv->touch == 0) {
+ priv->abs_x = packet[1] * (BYD_CONST_PAD_WIDTH / 256);
+ priv->abs_y = (255 - packet[2]) * (BYD_CONST_PAD_HEIGHT / 256);

drivers/input/mouse/byd.c new file +14 -0

+
+ /* needed to detect tap */
+ if (now_msecs - priv->last_touch_time > 64) {
+ priv->touch = 1;
+ }
+ }
+ break;
+ case BYD_PKT_RELATIVE:
+ {
+ int32_t rel_x, rel_y;
+
+ /* same as regular PS/2 psmouse protocoal */
+ rel_x = packet[1] ? (int) packet[1] - (int) ((packet[0] << 4) & 0x100) : 0;
+ rel_y = packet[2] ? (int) ((packet[0] << 3) & 0x100) - (int) packet[2] : 0;

drivers/input/mouse/byd.c line 338

Quoted 10 lines

drivers/input/mouse/byd.c new file +10 -0

+
+ /*
+ * experiments show relative mouse packets come in increments of
+ * 1 unit / 11 msecs (regardless of time delta between relative packets)
+ */
+ priv->abs_x += rel_x * 11;
+ priv->abs_y += rel_y * 11;
+
+ priv->touch = 1;
+ }

So can this not handle gestures/multitouch?

Cheers!
Chris

Hi Chris,

Reporting absolute position allows the synaptics and libinput xorg drivers to treat the BYD touchpad as a touchpad, rather than a mouse. This allows edge scrolling, tap to click, natural scrolling and any other location based single touch gesture to work.

I opted to completely disable the hardware multitouch gesture recognition (including two finger scroll) for a couple of reasons:

1. time delta between gesture packets was very large resulting in a rather jerky scrolling experience, especially compared to touchpad with real multitouch reporting.
2. Reporting absolute position and touch support enables the users to configure the touchpad in the touchpad settings section of gnome, cinnamon, etc because those applets configure synaptics and libinput. Otherwise xorg thinks it's just a mouse.
3. Enabling multitouch gesture recognition results in the mouse cursor freezing up when the user uses two fingers, one to move the mouse cursor and another to click. This is because movement packets stop getting sent while a gesture (such as pinch, rotate, etc) is being detected and/or reported. Disabling all hardware gesture detection, including two finger scroll, provides the most fluid user experience.

Regarding serio_pause_rx(), I was following a pattern similar to another touchpad driver in psmouse. That whole callback mechanism is required to report the touch had ended, since the BYD hardware only sends packets when a touch is occurring. Is there a better way?

I'll try to rebase and post an updated patch tonight.

best,
Richard

Quoted 4 lines · On Feb 2, 2016 4:41 PM, "Chris Diamand" <[email protected]…

Hi Richard,

Quoted 1 line

This adds proper single-touch support for BYD touchpads to the

psmouse input

Quoted 3 lines

Quoted 1 line

driver.

I posted a driver for the same touchpad a few weeks ago, which has

been merged

Quoted 1 line

into linux-next. There's some stuff in this patch which is missing in

my driver

Quoted 1 line

though, so we should definitely try and include that, and I'm very

curious

Quoted 3 lines

about the pseudo-absolute mode.

Quoted 1 line

This patch is against commit

b82dde0230439215b55e545880e90337ee16f51a (Merge tag

Quoted 2 lines

Quoted 2 lines

'please-pull-copy_file_range' of
git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux

<http://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux> ) of Linus' kernel

Quoted 4 lines

Quoted 1 line

branch.

Can you rebase against 'git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input

<http://git.kernel.org/pub/scm/linux/kernel/git/dtor/input>'?

Quoted 129 lines

Quoted 129 lines

(quoted diff) +128 -0

+/* BYD commands reverse engineered from windows driver */
+
+/*
+ * swipe gesture from off-pad to on-pad
+ *  0 : disable
+ *  1 : enable
+ */
+#define BYD_CMD_SET_OFFSCREEN_SWIPE             0xcc
+/*
+ * tap and drag delay time
+ *  0 : disable
+ *  1 - 8 : least to most delay
+ */
+#define BYD_CMD_SET_TAP_DRAG_DELAY_TIME         0xcf
+/*
+ * physical buttons function mapping
+ *  0 : enable
+ *  4 : normal
+ *  5 : left button custom command
+ *  6 : right button custom command
+ *  8 : disable
+ */
+#define BYD_CMD_SET_PHYSICAL_BUTTONS            0xd0
+/*
+ * absolute mode (1 byte X/Y resolution)
+ *  0 : disable
+ *  2 : enable
+ */
+#define BYD_CMD_SET_ABSOLUTE_MODE               0xd1
+/*
+ * two finger scrolling
+ *  1 : vertical
+ *  2 : horizontal
+ *  3 : vertical + horizontal
+ *  4 : disable
+ */
+#define BYD_CMD_SET_TWO_FINGER_SCROLL           0xd2
+/*
+ * handedness
+ *  1 : right handed
+ *  2 : left handed
+ */
+#define BYD_CMD_SET_HANDEDNESS                  0xd3
+/*
+ * tap to click
+ *  1 : enable
+ *  2 : disable
+ */
+#define BYD_CMD_SET_TAP                         0xd4
+/*
+ * tap and drag
+ *  1 : tap and hold to drag
+ *  2 : tap and hold to drag + lock
+ *  3 : disable
+ */
+#define BYD_CMD_SET_TAP_DRAG                    0xd5
+/*
+ * touch sensitivity
+ *  1 - 7 : least to most sensitive
+ */
+#define BYD_CMD_SET_TOUCH_SENSITIVITY           0xd6
+/*
+ * one finger scrolling
+ *  1 : vertical
+ *  2 : horizontal
+ *  3 : vertical + horizontal
+ *  4 : disable
+ */
+#define BYD_CMD_SET_ONE_FINGER_SCROLL           0xd7
+/*
+ * one finger scrolling function
+ *  1 : free scrolling
+ *  2 : edge motion
+ *  3 : free scrolling + edge motion
+ *  4 : disable
+ */
+#define BYD_CMD_SET_ONE_FINGER_SCROLL_FUNC      0xd8
+/*
+ * sliding speed
+ *  1 - 5 : slowest to fastest
+ */
+#define BYD_CMD_SET_SLIDING_SPEED               0xda
+/*
+ * edge motion
+ *  1 : disable
+ *  2 : enable when dragging
+ *  3 : enable when dragging and pointing
+ */
+#define BYD_CMD_SET_EDGE_MOTION                 0xdb
+/*
+ * left edge region size
+ *  0 - 7 : smallest to largest width
+ */
+#define BYD_CMD_SET_LEFT_EDGE_REGION            0xdc
+/*
+ * top edge region size
+ *  0 - 9 : smallest to largest height
+ */
+#define BYD_CMD_SET_TOP_EDGE_REGION             0xdd
+/*
+ * disregard palm press as clicks
+ *  1 - 6 : smallest to largest
+ */
+#define BYD_CMD_SET_PALM_CHECK                  0xde
+/* right edge region size
+ *  0 - 7 : smallest to largest width
+ */
+#define BYD_CMD_SET_RIGHT_EDGE_REGION           0xdf
+/*
+ * bottom edge region size
+ *  0 - 9 : smallest to largest height
+ */
+#define BYD_CMD_SET_BOTTOM_EDGE_REGION          0xe1
+/*
+ * multitouch gestures
+ *  1 : enable
+ *  2 : disable
+ */
+#define BYD_CMD_SET_MULTITOUCH                  0xe3
+/*
+ * edge motion speed
+ *  0 : control with finger pressure
+ *  1 - 9 : slowest to fastest
+ */
+#define BYD_CMD_SET_EDGE_MOTION_SPEED           0xe4
+/*
+ * two finger scolling function
+ *  0 : free scrolling

Quoted 8 lines

Quoted 6 lines

+ *  1 : free scrolling (with momentum)
+ *  2 : edge motion
+ *  3 : free scrolling (with momentum) + edge motion
+ *  4 : disable

+ */
+#define BYD_CMD_SET_TWO_FINGER_SCROLL_FUNC 0xe5

These are definitely worth merging into the existing driver - I never

got the

Quoted 15 lines

time to figure out all of the different settings.

Review

Quoted 11 lines

(quoted diff) +11 -0

+
+struct byd_data {
+ struct timer_list timer;
+ int32_t abs_x;
+ int32_t abs_y;
+ uint32_t last_touch_time;
+ uint32_t button_left      : 1;
+ uint32_t button_right     : 1;
+ uint32_t touch            : 1;
+};
+

It looks like whatever email client you used has broken the

formatting - when

Quoted 1 line

you resend, can you use something which will preserve whitespace

properly? See

Quoted 34 lines

'Documentation/email-clients.txt'.

Quoted 4 lines

(quoted diff) +4 -0

+static void byd_report_input(struct psmouse *psmouse)
+{
+ struct byd_data *priv = (struct byd_data *)psmouse->private;
+ struct input_dev *dev = psmouse->dev;

Review

Quoted 10 lines

(quoted diff) +10 -0

+
+ input_report_abs(dev, ABS_X, priv->abs_x);
+ input_report_abs(dev, ABS_Y, priv->abs_y);
+ input_report_key(dev, BTN_LEFT, priv->button_left);
+ input_report_key(dev, BTN_RIGHT, priv->button_right);
+ input_report_key(dev, BTN_TOUCH, priv->touch);
+ input_report_key(dev, BTN_TOOL_FINGER, priv->touch);
+
+ input_sync(dev);
+}

Could you explain generally why you're reporting in absolute mode? What advantage does it have over using relative reporting and turning off the absolute packets in the touchpad init sequence?

Quoted 13 lines

(quoted diff) +13 -0

+
+static void byd_clear_touch(unsigned long data)
+{
+ struct psmouse *psmouse = (struct psmouse *)data;
+ struct byd_data *priv = psmouse->private;
+
+ serio_pause_rx(psmouse->ps2dev.serio);
+
+ priv->touch = 0;
+ /*
+ * move cursor back to center of pad when we lose touch
+ * this specifically improves user experiencce when moving
+ * cursor with one finger, and pressing butoton with other

Quoted 12 lines

Quoted 5 lines

+ */
+ priv->abs_x = BYD_CONST_PAD_WIDTH / 2;
+ priv->abs_y = BYD_CONST_PAD_HEIGHT / 2;
+
+ byd_report_input(psmouse);

serio_pause_rx() takes a spinlock - might be worth checking that byd_report_input() doesn't do anything that might sleep.

Quoted 3 lines

+ switch (packet[3]) {
+ case BYD_PKT_ABSOLUTE:
+ /* on first touch, use the absolute packet to determine our start

location */

Quoted 8 lines

Quoted 8 lines

+ if (priv->touch == 0) {
+ priv->abs_x = packet[1] * (BYD_CONST_PAD_WIDTH / 256);
+ priv->abs_y = (255 - packet[2]) * (BYD_CONST_PAD_HEIGHT / 256); +
+ /* needed to detect tap */
+ if (now_msecs - priv->last_touch_time > 64) {
+ priv->touch = 1;
+ }

Quoted 8 lines

Quoted 8 lines

+ }
+ break;
+ case BYD_PKT_RELATIVE:
+ {
+ int32_t rel_x, rel_y;
+
+ /* same as regular PS/2 psmouse protocoal */
+ rel_x = packet[1] ? (int) packet[1] - (int) ((packet[0] << 4) &

0x100) : 0;

Quoted 1 line

Quoted 1 line

+ rel_y = packet[2] ? (int) ((packet[0] << 3) & 0x100) - (int)

packet[2] : 0;

Quoted 4 lines

Quoted 4 lines

+
+ /*
+ * experiments show relative mouse packets come in increments of
+ * 1 unit / 11 msecs (regardless of time delta between relative

packets)

Quoted 11 lines

Quoted 6 lines

+ */
+ priv->abs_x += rel_x * 11;
+ priv->abs_y += rel_y * 11;
+
+ priv->touch = 1;
+ }

So can this not handle gestures/multitouch?

Cheers!
Chris

Reporting absolute position allows the synaptics and libinput xorg drivers to treat the BYD touchpad as a touchpad, rather than a mouse. This allows edge scrolling, tap to click, natural scrolling and any other location based single touch gesture to work.

I opted to completely disable the hardware multitouch gesture recognition (including two finger scroll) for a couple of reasons:

1. time delta between gesture packets was very large resulting in a rather jerky scrolling experience, especially compared to touchpad with real multitouch reporting.
2. Reporting absolute position and touch support enables the users to configure the touchpad in the touchpad settings section of gnome, cinnamon, etc because those applets configure synaptics and libinput. Otherwise xorg thinks it's just a mouse.

3. Enabling multitouch gesture recognition results in the mouse cursor freezing up when the user uses two fingers, one to move the mouse cursor and another to click. This is because movement packets stop getting sent while a gesture (such as pinch, rotate, etc) is being detected and/or reported.

Disabling all hardware gesture detection, including two finger scroll, provides the most fluid user experience.

Regarding serio_pause_rx(), I was following a pattern similar to another touchpad driver in psmouse. That whole callback mechanism is required to report the touch had ended, since the BYD hardware only sends packets when a touch is occurring. Is there a better way?

I'll try to rebase and post an updated patch tonight.

Hi Richard,

Quoted 8 lines

Reporting absolute position allows the synaptics and libinput xorg drivers to treat the BYD touchpad as a touchpad, rather than a mouse. This allows edge scrolling, tap to click, natural scrolling and any other location based single touch gesture to work.

I opted to completely disable the hardware multitouch gesture recognition (including two finger scroll) for a couple of reasons:

Quoted 7 lines

1. time delta between gesture packets was very large resulting in a rather jerky scrolling experience, especially compared to touchpad with real multitouch reporting.
2. Reporting absolute position and touch support enables the users to configure the touchpad in the touchpad settings section of gnome, cinnamon, etc because those applets configure synaptics and libinput. Otherwise xorg thinks it's just a mouse.

This all sounds good - I look forward to trying your patch!

Also, how did you figure out how to enable the absolute packets? I couldn't find anything like that with the Windows driver I was using.

Quoted 6 lines

3. Enabling multitouch gesture recognition results in the mouse cursor freezing up when the user uses two fingers, one to move the mouse cursor and another to click. This is because movement packets stop getting sent while a gesture (such as pinch, rotate, etc) is being detected and/or reported.

So with your patch, how will this gesture work, if it can only recognise one finger at a time? I guess you'd have to enable the "double-tap then drag" thing in synaptics and use that?

Quoted 3 lines

Disabling all hardware gesture detection, including two finger scroll, provides the most fluid user experience.

Yep, I agree that if it works, good one-finger scrolling would be much better than the touchpad's internal gesture recognition.

Quoted 4 lines

Regarding serio_pause_rx(), I was following a pattern similar to another touchpad driver in psmouse. That whole callback mechanism is required to report the touch had ended, since the BYD hardware only sends packets when a touch is occurring. Is there a better way?

You're right, actually - I was worried that the input_report_* functions might sleep, but I just had a proper look and they don't.

Quoted 1 line

I'll try to rebase and post an updated patch tonight.

Cheers!
Chris

The Windows driver provides a visualization of the regions for the hardware edge scrolling capability. When entering that screen, a particular command pair is sent, and the touchpad starts sending interleaved REL and ABS packets. When leaving that screen, another particular command pair is sent, and the touchpad resumes the normal REL only stream.

Quoted 5 lines

The Windows driver provides a visualization of the regions for the hardware edge scrolling capability. When entering that screen, a particular command pair is sent, and the touchpad starts sending interleaved REL and ABS packets. When leaving that screen, another particular command pair is sent, and the touchpad resumes the normal REL only stream.

Good find! That's very crafty.

I've managed to apply your patch, and can confirm that it works - my initial impressions (using it for 15 mins...) are that even 256x256 resolution absolute mode + synaptics is much better than the touchpad's built-in gesture detection.

Let's work your patch into something which applies on top of the existing driver, and get it merged.

Cheers!
Chris

Rebased patch against 98ee377144935857d8ad5d7d70cdab1da4ede32e:

drivers/input/mouse/byd.c +4 -0

index 9425e0f..f213a08 100644
@@ -2,93 +2,276 @@
  * BYD TouchPad PS/2 mouse driver
  *
  * Copyright (C) 2015 Chris Diamand <[email protected]>
+ * Copyright (C) 2015 Richard Pospesel
+ * Copyright (C) 2015 Tai Chi Minh Ralph Eastwood
+ * Copyright (C) 2015 Martin Wimpress
+ * Copyright (C) 2015 Jay Kuri
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 as published

by
* the Free Software Foundation.

+ *
+ * Protocol of BYD Touch Pad reverse-engineered from windows driver:

+ * filename:  "byd touchpad driver - win7, 8, 8.1 - 2.4.1.102.zip"
+ * md5:       0d5e4660b98fca9587a0df212fca3048
+ * sha1:      97a0eca8edc482bf9d08ab9509084a514dad4c4b

+ * datasheet: http://bydit.com/userfiles/file/BTP10463-XXX.pdf
*/

#include <linux/delay.h>
#include <linux/input.h>
#include <linux/libps2.h>
#include <linux/serio.h>

drivers/input/mouse/byd.c +1 -7

+#include <linux/slab.h>
 
 #include "psmouse.h"
 #include "byd.h"
 
-#define PS2_Y_OVERFLOW	BIT_MASK(7)
-#define PS2_X_OVERFLOW	BIT_MASK(6)
-#define PS2_Y_SIGN	BIT_MASK(5)
-#define PS2_X_SIGN	BIT_MASK(4)
-#define PS2_ALWAYS_1	BIT_MASK(3)
-#define PS2_MIDDLE	BIT_MASK(2)
-#define PS2_RIGHT	BIT_MASK(1)

/*
- * The touchpad reports gestures in the last byte of each packet. It can take
- * any of the following values:

drivers/input/mouse/byd.c +1 -31

-/* One-finger scrolling in one of the edge scroll zones. */
-#define BYD_SCROLLUP		0xCA
-#define BYD_SCROLLDOWN		0x36
-#define BYD_SCROLLLEFT		0xCB
-#define BYD_SCROLLRIGHT		0x35
-/* Two-finger scrolling. */
-#define BYD_2DOWN		0x2B
-#define BYD_2UP			0xD5
-#define BYD_2LEFT		0xD6
-#define BYD_2RIGHT		0x2A
-/* Pinching in or out. */
-#define BYD_ZOOMOUT		0xD8
-#define BYD_ZOOMIN		0x28
-/* Three-finger swipe. */
-#define BYD_3UP			0xD3
-#define BYD_3DOWN		0x2D
-#define BYD_3LEFT		0xD4
-#define BYD_3RIGHT		0x2C
-/* Four-finger swipe. */
-#define BYD_4UP			0xCD
-#define BYD_4DOWN		0x33
-
-int byd_detect(struct psmouse *psmouse, bool set_properties)
-{
-	struct ps2dev *ps2dev = &psmouse->ps2dev;
-	unsigned char param[4];
+/* BYD commands reverse engineered from windows driver */
 
-	param[0] = 0x03;
-	param[1] = 0x00;
-	param[2] = 0x00;
-	param[3] = 0x00;
-

drivers/input/mouse/byd.c +123 -0

+/*
+ * Swipe gesture from off-pad to on-pad
+ *  0 : disable
+ *  1 : enable
+ */
+#define BYD_CMD_SET_OFFSCREEN_SWIPE        0x10cc
+/*
+ * Tap and drag delay time
+ *  0 : disable
+ *  1 - 8 : least to most delay
+ */
+#define BYD_CMD_SET_TAP_DRAG_DELAY_TIME    0x10cf
+/*
+ * Physical buttons function mapping
+ *  0 : enable
+ *  4 : normal
+ *  5 : left button custom command
+ *  6 : right button custom command
+ *  8 : disable
+ */
+#define BYD_CMD_SET_PHYSICAL_BUTTONS       0x10d0
+/*
+ * Absolute mode (1 byte X/Y resolution)
+ *  0 : disable
+ *  2 : enable
+ */
+#define BYD_CMD_SET_ABSOLUTE_MODE          0x10d1
+/*
+ * Two finger scrolling
+ *  1 : vertical
+ *  2 : horizontal
+ *  3 : vertical + horizontal
+ *  4 : disable
+ */
+#define BYD_CMD_SET_TWO_FINGER_SCROLL      0x10d2
+/*
+ * Handedness
+ *  1 : right handed
+ *  2 : left handed
+ */
+#define BYD_CMD_SET_HANDEDNESS             0x10d3
+/*
+ * Tap to click
+ *  1 : enable
+ *  2 : disable
+ */
+#define BYD_CMD_SET_TAP                    0x10d4
+/*
+ * Tap and drag
+ *  1 : tap and hold to drag
+ *  2 : tap and hold to drag + lock
+ *  3 : disable
+ */
+#define BYD_CMD_SET_TAP_DRAG               0x10d5
+/*
+ * Touch sensitivity
+ *  1 - 7 : least to most sensitive
+ */
+#define BYD_CMD_SET_TOUCH_SENSITIVITY      0x10d6
+/*
+ * One finger scrolling
+ *  1 : vertical
+ *  2 : horizontal
+ *  3 : vertical + horizontal
+ *  4 : disable
+ */
+#define BYD_CMD_SET_ONE_FINGER_SCROLL      0x10d7
+/*
+ * One finger scrolling function
+ *  1 : free scrolling
+ *  2 : edge motion
+ *  3 : free scrolling + edge motion
+ *  4 : disable
+ */
+#define BYD_CMD_SET_ONE_FINGER_SCROLL_FUNC 0x10d8
+/*
+ * Sliding speed
+ *  1 - 5 : slowest to fastest
+ */
+#define BYD_CMD_SET_SLIDING_SPEED          0x10da
+/*
+ * Edge motion
+ *  1 : disable
+ *  2 : enable when dragging
+ *  3 : enable when dragging and pointing
+ */
+#define BYD_CMD_SET_EDGE_MOTION            0x10db
+/*
+ * Left edge region size
+ *  0 - 7 : smallest to largest width
+ */
+#define BYD_CMD_SET_LEFT_EDGE_REGION       0x10dc
+/*
+ * Top edge region size
+ *  0 - 9 : smallest to largest height
+ */
+#define BYD_CMD_SET_TOP_EDGE_REGION        0x10dd
+/*
+ * Disregard palm press as clicks
+ *  1 - 6 : smallest to largest
+ */
+#define BYD_CMD_SET_PALM_CHECK             0x10de
+/*
+ * Right edge region size
+ *  0 - 7 : smallest to largest width
+ */
+#define BYD_CMD_SET_RIGHT_EDGE_REGION      0x10df
+/*
+ * Bottom edge region size
+ *  0 - 9 : smallest to largest height
+ */
+#define BYD_CMD_SET_BOTTOM_EDGE_REGION     0x10e1
+/*
+ * Multitouch gestures
+ *  1 : enable
+ *  2 : disable
+ */
+#define BYD_CMD_SET_MULTITOUCH             0x10e3
+/*
+ * Edge motion speed
+ *  0 : control with finger pressure
+ *  1 - 9 : slowest to fastest
+ */

drivers/input/mouse/byd.c +2 -2

-	if (param[1] != 0x03 || param[2] != 0x64)
-		return -ENODEV;
+/*
+ * The touchpad generates a mixture of absolute and relative packets,

indicated
+ * by the the last byte of each packet being set to one of the following:
+ */

drivers/input/mouse/byd.c +4 -1

+#define BYD_PACKET_ABSOLUTE	0xF8
+#define BYD_PACKET_RELATIVE	0x00
 
-	psmouse_dbg(psmouse, "BYD touchpad detected\n");
+/*
+ * With multitouch gestures enabled, the following packets will be sent

from
+ * the touchpad:
+ */

drivers/input/mouse/byd.c +15 -0

+#define BYD_PACKET_PINCH_IN                    0xd8
+#define BYD_PACKET_PINCH_OUT                   0x28
+#define BYD_PACKET_ROTATE_CLOCKWISE            0x29
+#define BYD_PACKET_ROTATE_ANTICLOCKWISE        0xd7
+#define BYD_PACKET_TWO_FINGER_SCROLL_RIGHT     0x2a
+#define BYD_PACKET_TWO_FINGER_SCROLL_DOWN      0x2b
+#define BYD_PACKET_TWO_FINGER_SCROLL_UP        0xd5
+#define BYD_PACKET_TWO_FINGER_SCROLL_LEFT      0xd6
+#define BYD_PACKET_THREE_FINGER_SWIPE_RIGHT    0x2c
+#define BYD_PACKET_THREE_FINGER_SWIPE_DOWN     0x2d
+#define BYD_PACKET_THREE_FINGER_SWIPE_UP       0xd3
+#define BYD_PACKET_THREE_FINGER_SWIPE_LEFT     0xd4
+#define BYD_PACKET_FOUR_FINGER_DOWN            0x33
+#define BYD_PACKET_FOUR_FINGER_UP              0xcd
+#define BYD_PACKET_REGION_SCROLL_RIGHT         0x35

drivers/input/mouse/byd.c +4 -0

+
+struct byd_data {
+	struct timer_list timer;
+	s32 abs_x;

drivers/input/mouse/byd.c +4 -4

+	struct input_dev *dev = psmouse->dev;
 
-	if (set_properties) {
-		psmouse->vendor = "BYD";
-		psmouse->name = "TouchPad";
-	}
+	input_report_abs(dev, ABS_X, priv->abs_x);
+	input_report_abs(dev, ABS_Y, priv->abs_y);
+	input_report_key(dev, BTN_LEFT, priv->btn_left);

drivers/input/mouse/byd.c +29 -7

+	struct byd_data *priv = psmouse->private;
+
+	serio_pause_rx(psmouse->ps2dev.serio);
+	priv->touch = false;
+	/*
+	 * Move cursor back to center of pad when we lose touch - this
+	 * specifically improves user experience when moving cursor with one
+	 * finger, and pressing a button with another.
+	 */
+	priv->abs_x = BYD_CONST_PAD_WIDTH / 2;
+	priv->abs_y = BYD_CONST_PAD_HEIGHT / 2;
+	byd_report_input(psmouse);
+
+	serio_continue_rx(psmouse->ps2dev.serio);
 }
 
 static psmouse_ret_t byd_process_byte(struct psmouse *psmouse)
 {
-	struct input_dev *dev = psmouse->dev;
+	struct byd_data *priv = psmouse->private;
+	u32 now_msecs = jiffies_to_msecs(jiffies);
 	u8 *pkt = psmouse->packet;
 
 	if (psmouse->pktcnt > 0 && !(pkt[0] & PS2_ALWAYS_1)) {

@@ -102,53 +285,37 @@ static psmouse_ret_t byd_process_byte(struct psmouse
 *psmouse)
 
 	/* Otherwise, a full packet has been received */
 	switch (pkt[3]) {
-	case 0: {
+	case BYD_PACKET_ABSOLUTE:
+		/* Only use absolute packets for the start of movement. */
+		if (!priv->touch) {
+			priv->abs_x = pkt[1] * (BYD_CONST_PAD_WIDTH / 256);
+			priv->abs_y = (255 - pkt[2]) *
+				      (BYD_CONST_PAD_HEIGHT / 256);
+
+			/* needed to detect tap */
+			if (now_msecs - priv->last_touch_time > 64)
+				priv->touch = true;
+		}
+		break;
+	case BYD_PACKET_RELATIVE: {
 		/* Standard packet */
 		/* Sign-extend if a sign bit is set. */
-		unsigned int signx = pkt[0] & PS2_X_SIGN ? ~0xFF : 0;
-		unsigned int signy = pkt[0] & PS2_Y_SIGN ? ~0xFF : 0;
-		int dx = signx | (int) pkt[1];
-		int dy = signy | (int) pkt[2];
-

drivers/input/mouse/byd.c +2 -31

+
+		priv->touch = true;
 		break;
 	}
-
-	case BYD_SCROLLDOWN:
-	case BYD_2DOWN:
-		input_report_rel(dev, REL_WHEEL, -1);
-		break;
-
-	case BYD_SCROLLUP:
-	case BYD_2UP:
-		input_report_rel(dev, REL_WHEEL, 1);
-		break;
-
-	case BYD_SCROLLLEFT:
-	case BYD_2LEFT:
-		input_report_rel(dev, REL_HWHEEL, -1);
-		break;
-
-	case BYD_SCROLLRIGHT:
-	case BYD_2RIGHT:
-		input_report_rel(dev, REL_HWHEEL, 1);
-		break;
-
-	case BYD_ZOOMOUT:
-	case BYD_ZOOMIN:
-	case BYD_3UP:
-	case BYD_3DOWN:
-	case BYD_3LEFT:
-	case BYD_3RIGHT:
-	case BYD_4UP:
-	case BYD_4DOWN:
-		break;
-
 	default:
 		psmouse_warn(psmouse,

drivers/input/mouse/byd.c +8 -72

 			     "Unrecognized Z: pkt = %02x %02x %02x %02x\n",

@@ -157,134 +324,76 @@ static psmouse_ret_t byd_process_byte(struct psmouse
 *psmouse)
 		return PSMOUSE_BAD_DATA;
 	}
 
-	input_sync(dev);
+	priv->btn_left = pkt[0] & PS2_LEFT;
+	priv->btn_right = pkt[0] & PS2_RIGHT;
 
-	return PSMOUSE_FULL_PACKET;
-}
+	byd_report_input(psmouse);
 
-/* Send a sequence of bytes, where each is ACKed before the next is sent.
 */
-static int byd_send_sequence(struct psmouse *psmouse, const u8 *seq, size_t
 len)
-{
-	unsigned int i;
-
-	for (i = 0; i < len; ++i) {
-		if (ps2_command(&psmouse->ps2dev, NULL, seq[i]))
-			return -1;
+	/* Reset time since last touch. */
+	if (priv->touch) {
+		priv->last_touch_time = now_msecs;
+		mod_timer(&priv->timer, jiffies + msecs_to_jiffies(64));
 	}
-	return 0;
-}
-
-/* Keep scrolling after fingers are removed. */
-#define SCROLL_INERTIAL		0x01
-#define SCROLL_NO_INERTIAL	0x02
-
-/* Clicking can be done by tapping or pressing. */
-#define CLICK_BOTH		0x01
-/* Clicking can only be done by pressing. */
-#define CLICK_PRESS_ONLY	0x02
-
-static int byd_enable(struct psmouse *psmouse)
-{
-	const u8 seq1[] = { 0xE2, 0x00, 0xE0, 0x02, 0xE0 };
-	const u8 seq2[] = {
-		0xD3, 0x01,
-		0xD0, 0x00,
-		0xD0, 0x04,
-		/* Whether clicking is done by tapping or pressing. */
-		0xD4, CLICK_PRESS_ONLY,
-		0xD5, 0x01,
-		0xD7, 0x03,
-		/* Vertical and horizontal one-finger scroll zone inertia. */
-		0xD8, SCROLL_INERTIAL,
-		0xDA, 0x05,
-		0xDB, 0x02,
-		0xE4, 0x05,
-		0xD6, 0x01,
-		0xDE, 0x04,
-		0xE3, 0x01,
-		0xCF, 0x00,
-		0xD2, 0x03,
-		/* Vertical and horizontal two-finger scrolling inertia. */
-		0xE5, SCROLL_INERTIAL,
-		0xD9, 0x02,
-		0xD9, 0x07,
-		0xDC, 0x03,
-		0xDD, 0x03,
-		0xDF, 0x03,
-		0xE1, 0x03,
-		0xD1, 0x00,
-		0xCE, 0x00,
-		0xCC, 0x00,
-		0xE0, 0x00,
-		0xE2, 0x01
-	};
-	u8 param[4];
-
-	if (byd_send_sequence(psmouse, seq1, ARRAY_SIZE(seq1)))
-		return -1;
-
-	/* Send a 0x01 command, which should return 4 bytes. */
-	if (ps2_command(&psmouse->ps2dev, param, 0x0401))
-		return -1;
 
-	if (byd_send_sequence(psmouse, seq2, ARRAY_SIZE(seq2)))
-		return -1;
-
-	return 0;
+	return PSMOUSE_FULL_PACKET;
 }
 
-/*
- * Send the set of PS/2 commands required to make it identify as an

drivers/input/mouse/byd.c +36 -29

 	const struct {
 		u16 command;
 		u8 arg;
 	} seq[] = {
-		{ PSMOUSE_CMD_RESET_BAT, 0 },
-		{ PSMOUSE_CMD_RESET_BAT, 0 },
-		{ PSMOUSE_CMD_GETID, 0 },
-		{ PSMOUSE_CMD_SETSCALE11, 0 },
-		{ PSMOUSE_CMD_SETSCALE11, 0 },
-		{ PSMOUSE_CMD_SETSCALE11, 0 },
-		{ PSMOUSE_CMD_GETINFO, 0 },
-		{ PSMOUSE_CMD_SETRES, 0x03 },
+		/*
+		 * Intellimouse initialization sequence, to get 4-byte instead
+		 * of 3-byte packets.
+		 */
 		{ PSMOUSE_CMD_SETRATE, 0xC8 },
 		{ PSMOUSE_CMD_SETRATE, 0x64 },
 		{ PSMOUSE_CMD_SETRATE, 0x50 },
 		{ PSMOUSE_CMD_GETID, 0 },
-		{ PSMOUSE_CMD_SETRATE, 0xC8 },
-		{ PSMOUSE_CMD_SETRATE, 0xC8 },
-		{ PSMOUSE_CMD_SETRATE, 0x50 },
-		{ PSMOUSE_CMD_GETID, 0 },
-		{ PSMOUSE_CMD_SETRATE, 0x64 },
-		{ PSMOUSE_CMD_SETRES, 0x03 },
-		{ PSMOUSE_CMD_ENABLE, 0 }
+		{ PSMOUSE_CMD_ENABLE, 0 },
+		/*
+		 * BYD-specific initialization, which enables absolute mode and
+		 * (if desired), the touchpad's built-in gesture detection.
+		 */
+		{ 0x10E2, 0x00 },
+		{ 0x10E0, 0x02 },
+		/* The touchpad should reply with 4 seemingly-random bytes */
+		{ 0x14E0, 0x01 },
+		/* Pairs of parameters and values. */
+		{ BYD_CMD_SET_HANDEDNESS, 0x01 },
+		{ BYD_CMD_SET_PHYSICAL_BUTTONS, 0x04 },
+		{ BYD_CMD_SET_TAP, 0x02 },
+		{ BYD_CMD_SET_ONE_FINGER_SCROLL, 0x04 },
+		{ BYD_CMD_SET_ONE_FINGER_SCROLL_FUNC, 0x04 },
+		{ BYD_CMD_SET_EDGE_MOTION, 0x01 },
+		{ BYD_CMD_SET_PALM_CHECK, 0x00 },
+		{ BYD_CMD_SET_MULTITOUCH, 0x02 },
+		{ BYD_CMD_SET_TWO_FINGER_SCROLL, 0x04 },
+		{ BYD_CMD_SET_TWO_FINGER_SCROLL_FUNC, 0x04 },
+		{ BYD_CMD_SET_LEFT_EDGE_REGION, 0x00 },
+		{ BYD_CMD_SET_TOP_EDGE_REGION, 0x00 },
+		{ BYD_CMD_SET_RIGHT_EDGE_REGION, 0x00 },
+		{ BYD_CMD_SET_BOTTOM_EDGE_REGION, 0x00 },
+		{ BYD_CMD_SET_ABSOLUTE_MODE, 0x02 },
+		/* Finalize initialization. */
+		{ 0x10E0, 0x00 },
+		{ 0x10E2, 0x01 },
 	};
 
-	memset(param, 0, sizeof(param));
 	for (i = 0; i < ARRAY_SIZE(seq); ++i) {
+		memset(param, 0, sizeof(param));
 		param[0] = seq[i].arg;
 		if (ps2_command(ps2dev, param, seq[i].command))
-			return -1;
-	}
-
-	return 0;
-}
-
-static int byd_reset_touchpad(struct psmouse *psmouse)
-{
-	if (byd_send_intellimouse_sequence(psmouse))
-		return -EIO;
-
-	if (byd_enable(psmouse))
-		return -EIO;
+			return -EIO;
 
+	}
+	psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);

drivers/input/mouse/byd.c +69 -3

 	return 0;
 }

@@ -314,9 +423,50 @@ static int byd_reconnect(struct psmouse *psmouse)
 	return 0;
 }
 
+static void byd_disconnect(struct psmouse *psmouse)
+{
+	struct byd_data *priv = psmouse->private;
+
+	if (priv) {
+		del_timer(&priv->timer);
+		kfree(psmouse->private);
+		psmouse->private = NULL;
+	}
+}
+
+int byd_detect(struct psmouse *psmouse, bool set_properties)
+{
+	struct ps2dev *ps2dev = &psmouse->ps2dev;
+	u8 param[4] = {0x03, 0x00, 0x00, 0x00};
+
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+		return -1;
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+		return -1;
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+		return -1;
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+		return -1;
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
+		return -1;
+
+	if (param[1] != 0x03 || param[2] != 0x64)
+		return -ENODEV;
+
+	psmouse_dbg(psmouse, "BYD touchpad detected\n");
+
+	if (set_properties) {
+		psmouse->vendor = "BYD";
+		psmouse->name = "TouchPad";
+	}
+
+	return 0;
+}
+
 int byd_init(struct psmouse *psmouse)
 {
 	struct input_dev *dev = psmouse->dev;
+	struct byd_data *priv;
 
 	if (psmouse_reset(psmouse))
 		return -EIO;

@@ -324,14 +474,39 @@ int byd_init(struct psmouse *psmouse)
 	if (byd_reset_touchpad(psmouse))
 		return -EIO;
 
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	memset(priv, 0, sizeof(*priv));
+	setup_timer(&priv->timer, byd_clear_touch, (unsigned long) psmouse);
+
+	psmouse->private = priv;
+	psmouse->disconnect = byd_disconnect;
 	psmouse->reconnect = byd_reconnect;
 	psmouse->protocol_handler = byd_process_byte;
 	psmouse->pktsize = 4;
 	psmouse->resync_time = 0;
 
-	__set_bit(BTN_MIDDLE, dev->keybit);
-	__set_bit(REL_WHEEL, dev->relbit);
-	__set_bit(REL_HWHEEL, dev->relbit);
+	__set_bit(INPUT_PROP_POINTER, dev->propbit);
+	/* Touchpad */
+	__set_bit(BTN_TOUCH, dev->keybit);
+	__set_bit(BTN_TOOL_FINGER, dev->keybit);
+	/* Buttons */
+	__set_bit(BTN_LEFT, dev->keybit);
+	__set_bit(BTN_RIGHT, dev->keybit);
+	__clear_bit(BTN_MIDDLE, dev->keybit);
+
+	/* Absolute position */
+	__set_bit(EV_ABS, dev->evbit);
+	input_set_abs_params(dev, ABS_X, 0, BYD_CONST_PAD_WIDTH, 0, 0);
+	input_set_abs_params(dev, ABS_Y, 0, BYD_CONST_PAD_HEIGHT, 0, 0);
+	input_abs_set_res(dev, ABS_X, BYD_CONST_PAD_RESOLUTION);
+	input_abs_set_res(dev, ABS_Y, BYD_CONST_PAD_RESOLUTION);
+	/* No relative support */
+	__clear_bit(EV_REL, dev->evbit);
+	__clear_bit(REL_X, dev->relbit);
+	__clear_bit(REL_Y, dev->relbit);
 
 	return 0;
 }

drivers/input/mouse/psmouse-base.c +1 -1

index 39d1bec..5784e20 100644
@@ -846,7 +846,7 @@ static const struct psmouse_protocol psmouse_protocols[]
 = {
 #ifdef CONFIG_MOUSE_PS2_BYD
 	{
 		.type		= PSMOUSE_BYD,
-		.name		= "BydPS/2",
+		.name		= "BYDPS/2",
 		.alias		= "byd",
 		.detect		= byd_detect,

.init = byd_init,

Hi Richard,

Thanks for this.

Quoted 1 line

Rebased patch against 98ee377144935857d8ad5d7d70cdab1da4ede32e:

Can you include a proper commit message and Signed-off-by line?

Quoted 15 lines

drivers/input/mouse/byd.c +4 -0

index 9425e0f..f213a08 100644
@@ -2,93 +2,276 @@
   * BYD TouchPad PS/2 mouse driver
   *
   * Copyright (C) 2015 Chris Diamand <[email protected]>
+ * Copyright (C) 2015 Richard Pospesel
+ * Copyright (C) 2015 Tai Chi Minh Ralph Eastwood
+ * Copyright (C) 2015 Martin Wimpress
+ * Copyright (C) 2015 Jay Kuri
   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 as published

Quoted 2 lines

by
* the Free Software Foundation.

Your email client is still mangling the patch - use git send-email or similar next time. Also try sending it to yourself and then applying the patch to check it's worked.

Quoted 30 lines

+ *
+ * Protocol of BYD Touch Pad reverse-engineered from windows driver:

+ * filename:  "byd touchpad driver - win7, 8, 8.1 - 2.4.1.102.zip"
+ * md5:       0d5e4660b98fca9587a0df212fca3048
+ * sha1:      97a0eca8edc482bf9d08ab9509084a514dad4c4b

+ * datasheet: http://bydit.com/userfiles/file/BTP10463-XXX.pdf
*/

  #include <linux/delay.h>
  #include <linux/input.h>
  #include <linux/libps2.h>
  #include <linux/serio.h>

drivers/input/mouse/byd.c +6 -8

+#include <linux/slab.h>
 
  #include "psmouse.h"
  #include "byd.h"
 
-#define PS2_Y_OVERFLOW	BIT_MASK(7)
-#define PS2_X_OVERFLOW	BIT_MASK(6)
-#define PS2_Y_SIGN	BIT_MASK(5)
-#define PS2_X_SIGN	BIT_MASK(4)
-#define PS2_ALWAYS_1	BIT_MASK(3)
-#define PS2_MIDDLE	BIT_MASK(2)
-#define PS2_RIGHT	BIT_MASK(1)
-#define PS2_LEFT	BIT_MASK(0)
+/* PS2 Bits */
+#define PS2_Y_OVERFLOW BIT_MASK(7)
+#define PS2_X_OVERFLOW BIT_MASK(6)
+#define PS2_Y_SIGN     BIT_MASK(5)
+#define PS2_X_SIGN     BIT_MASK(4)

drivers/input/mouse/byd.c

Quoted 4 lines

drivers/input/mouse/byd.c +4 -0

+#define PS2_ALWAYS_1   BIT_MASK(3)
+#define PS2_MIDDLE     BIT_MASK(2)
+#define PS2_RIGHT      BIT_MASK(1)
+#define PS2_LEFT       BIT_MASK(0)

The tabs between these were deliberate - no need to change them. Do you have your tab width set to eight spaces? If you've got it set to four then it'll look wrong.

Quoted 5 lines

/*
- * The touchpad reports gestures in the last byte of each packet. It can take
- * any of the following values:

Another example of your email client wrapping lines incorrectly.

drivers/input/mouse/byd.c

Quoted 13 lines

+ * BYD pad constants
+ *
+ * True device resolution is unknown, however experiments show the
+ * resolution is about 111 units/mm.
+ * Absolute coordinate packets are in the range 0-255 for both X and Y
+ * we pick ABS_X/ABS_Y dimensions which are multiples of 256 and in
+ * the right ballpark given the touchpad's physical dimensions and estimate
+ * resolution per spec sheet, device active area dimensions are
+ * 101.6 x 60.1 mm.
*/

drivers/input/mouse/byd.c +3 -0

+#define BYD_CONST_PAD_WIDTH	     11264
+#define BYD_CONST_PAD_HEIGHT     6656
+#define BYD_CONST_PAD_RESOLUTION 111

Do these need to include "CONST"? It's pretty obvious that they're constant from the capitalization.

Quoted 40 lines

drivers/input/mouse/byd.c +1 -36

-/* One-finger scrolling in one of the edge scroll zones. */
-#define BYD_SCROLLUP		0xCA
-#define BYD_SCROLLDOWN		0x36
-#define BYD_SCROLLLEFT		0xCB
-#define BYD_SCROLLRIGHT		0x35
-/* Two-finger scrolling. */
-#define BYD_2DOWN		0x2B
-#define BYD_2UP			0xD5
-#define BYD_2LEFT		0xD6
-#define BYD_2RIGHT		0x2A
-/* Pinching in or out. */
-#define BYD_ZOOMOUT		0xD8
-#define BYD_ZOOMIN		0x28
-/* Three-finger swipe. */
-#define BYD_3UP			0xD3
-#define BYD_3DOWN		0x2D
-#define BYD_3LEFT		0xD4
-#define BYD_3RIGHT		0x2C
-/* Four-finger swipe. */
-#define BYD_4UP			0xCD
-#define BYD_4DOWN		0x33
-
-int byd_detect(struct psmouse *psmouse, bool set_properties)
-{
-	struct ps2dev *ps2dev = &psmouse->ps2dev;
-	unsigned char param[4];
+/* BYD commands reverse engineered from windows driver */
 
-	param[0] = 0x03;
-	param[1] = 0x00;
-	param[2] = 0x00;
-	param[3] = 0x00;
-
-	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
-		return -1;
-	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
-		return -1;
-	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))

drivers/input/mouse/byd.c

Quoted 5 lines

drivers/input/mouse/byd.c +0 -5

-		return -1;
-	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
-		return -1;
-	if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
-		return -1;

Did you need to move this function? No technical objections, but it confuses the patch a bit.

Quoted 125 lines

drivers/input/mouse/byd.c +123 -0

+/*
+ * Swipe gesture from off-pad to on-pad
+ *  0 : disable
+ *  1 : enable
+ */
+#define BYD_CMD_SET_OFFSCREEN_SWIPE        0x10cc
+/*
+ * Tap and drag delay time
+ *  0 : disable
+ *  1 - 8 : least to most delay
+ */
+#define BYD_CMD_SET_TAP_DRAG_DELAY_TIME    0x10cf
+/*
+ * Physical buttons function mapping
+ *  0 : enable
+ *  4 : normal
+ *  5 : left button custom command
+ *  6 : right button custom command
+ *  8 : disable
+ */
+#define BYD_CMD_SET_PHYSICAL_BUTTONS       0x10d0
+/*
+ * Absolute mode (1 byte X/Y resolution)
+ *  0 : disable
+ *  2 : enable
+ */
+#define BYD_CMD_SET_ABSOLUTE_MODE          0x10d1
+/*
+ * Two finger scrolling
+ *  1 : vertical
+ *  2 : horizontal
+ *  3 : vertical + horizontal
+ *  4 : disable
+ */
+#define BYD_CMD_SET_TWO_FINGER_SCROLL      0x10d2
+/*
+ * Handedness
+ *  1 : right handed
+ *  2 : left handed
+ */
+#define BYD_CMD_SET_HANDEDNESS             0x10d3
+/*
+ * Tap to click
+ *  1 : enable
+ *  2 : disable
+ */
+#define BYD_CMD_SET_TAP                    0x10d4
+/*
+ * Tap and drag
+ *  1 : tap and hold to drag
+ *  2 : tap and hold to drag + lock
+ *  3 : disable
+ */
+#define BYD_CMD_SET_TAP_DRAG               0x10d5
+/*
+ * Touch sensitivity
+ *  1 - 7 : least to most sensitive
+ */
+#define BYD_CMD_SET_TOUCH_SENSITIVITY      0x10d6
+/*
+ * One finger scrolling
+ *  1 : vertical
+ *  2 : horizontal
+ *  3 : vertical + horizontal
+ *  4 : disable
+ */
+#define BYD_CMD_SET_ONE_FINGER_SCROLL      0x10d7
+/*
+ * One finger scrolling function
+ *  1 : free scrolling
+ *  2 : edge motion
+ *  3 : free scrolling + edge motion
+ *  4 : disable
+ */
+#define BYD_CMD_SET_ONE_FINGER_SCROLL_FUNC 0x10d8
+/*
+ * Sliding speed
+ *  1 - 5 : slowest to fastest
+ */
+#define BYD_CMD_SET_SLIDING_SPEED          0x10da
+/*
+ * Edge motion
+ *  1 : disable
+ *  2 : enable when dragging
+ *  3 : enable when dragging and pointing
+ */
+#define BYD_CMD_SET_EDGE_MOTION            0x10db
+/*
+ * Left edge region size
+ *  0 - 7 : smallest to largest width
+ */
+#define BYD_CMD_SET_LEFT_EDGE_REGION       0x10dc
+/*
+ * Top edge region size
+ *  0 - 9 : smallest to largest height
+ */
+#define BYD_CMD_SET_TOP_EDGE_REGION        0x10dd
+/*
+ * Disregard palm press as clicks
+ *  1 - 6 : smallest to largest
+ */
+#define BYD_CMD_SET_PALM_CHECK             0x10de
+/*
+ * Right edge region size
+ *  0 - 7 : smallest to largest width
+ */
+#define BYD_CMD_SET_RIGHT_EDGE_REGION      0x10df
+/*
+ * Bottom edge region size
+ *  0 - 9 : smallest to largest height
+ */
+#define BYD_CMD_SET_BOTTOM_EDGE_REGION     0x10e1
+/*
+ * Multitouch gestures
+ *  1 : enable
+ *  2 : disable
+ */
+#define BYD_CMD_SET_MULTITOUCH             0x10e3
+/*
+ * Edge motion speed
+ *  0 : control with finger pressure
+ *  1 - 9 : slowest to fastest
+ */

drivers/input/mouse/byd.c

Quoted 10 lines

drivers/input/mouse/byd.c +10 -0

+#define BYD_CMD_SET_EDGE_MOTION_SPEED      0x10e4
+/*
+ * Two finger scolling function
+ *  0 : free scrolling
+ *  1 : free scrolling (with momentum)
+ *  2 : edge motion
+ *  3 : free scrolling (with momentum) + edge motion
+ *  4 : disable
+ */
+#define BYD_CMD_SET_TWO_FINGER_SCROLL_FUNC 0x10e5

Good effort figuring all the different settings by the way.

Quoted 36 lines

drivers/input/mouse/byd.c +2 -2

-	if (param[1] != 0x03 || param[2] != 0x64)
-		return -ENODEV;
+/*
+ * The touchpad generates a mixture of absolute and relative packets,

indicated
+ * by the the last byte of each packet being set to one of the following:
+ */

drivers/input/mouse/byd.c +4 -1

+#define BYD_PACKET_ABSOLUTE	0xF8
+#define BYD_PACKET_RELATIVE	0x00
 
-	psmouse_dbg(psmouse, "BYD touchpad detected\n");
+/*
+ * With multitouch gestures enabled, the following packets will be sent

from
+ * the touchpad:
+ */

drivers/input/mouse/byd.c +20 -0

+#define BYD_PACKET_PINCH_IN                    0xd8
+#define BYD_PACKET_PINCH_OUT                   0x28
+#define BYD_PACKET_ROTATE_CLOCKWISE            0x29
+#define BYD_PACKET_ROTATE_ANTICLOCKWISE        0xd7
+#define BYD_PACKET_TWO_FINGER_SCROLL_RIGHT     0x2a
+#define BYD_PACKET_TWO_FINGER_SCROLL_DOWN      0x2b
+#define BYD_PACKET_TWO_FINGER_SCROLL_UP        0xd5
+#define BYD_PACKET_TWO_FINGER_SCROLL_LEFT      0xd6
+#define BYD_PACKET_THREE_FINGER_SWIPE_RIGHT    0x2c
+#define BYD_PACKET_THREE_FINGER_SWIPE_DOWN     0x2d
+#define BYD_PACKET_THREE_FINGER_SWIPE_UP       0xd3
+#define BYD_PACKET_THREE_FINGER_SWIPE_LEFT     0xd4
+#define BYD_PACKET_FOUR_FINGER_DOWN            0x33
+#define BYD_PACKET_FOUR_FINGER_UP              0xcd
+#define BYD_PACKET_REGION_SCROLL_RIGHT         0x35
+#define BYD_PACKET_REGION_SCROLL_DOWN          0x36
+#define BYD_PACKET_REGION_SCROLL_UP            0xca
+#define BYD_PACKET_REGION_SCROLL_LEFT          0xcb
+#define BYD_PACKET_RIGHT_CORNER_CLICK          0xd2
+#define BYD_PACKET_LEFT_CORNER_CLICK           0x2e

drivers/input/mouse/byd.c

Quoted 5 lines

drivers/input/mouse/byd.c +5 -0

+#define BYD_PACKET_LEFT_AND_RIGHT_CORNER_CLICK 0x2f
+#define BYD_PACKET_ONTO_PAD_SWIPE_RIGHT        0x37
+#define BYD_PACKET_ONTO_PAD_SWIPE_DOWN         0x30
+#define BYD_PACKET_ONTO_PAD_SWIPE_UP           0xd0
+#define BYD_PACKET_ONTO_PAD_SWIPE_LEFT         0xc9

Can you merge this with the existing list of packet[3] values? Again, just to keep the diff smaller/simpler.

Quoted 10 lines

drivers/input/mouse/byd.c +9 -0

+
+struct byd_data {
+	struct timer_list timer;
+	s32 abs_x;
+	s32 abs_y;
+	u32 last_touch_time;
+	bool btn_left  : 1;
+	bool btn_right : 1;
+	bool touch     : 1;

drivers/input/mouse/byd.c

Quoted 5 lines

drivers/input/mouse/byd.c +5 -0

+};
+
+static void byd_report_input(struct psmouse *psmouse)
+{
+	struct byd_data *priv = (struct byd_data *)psmouse->private;

I've just noticed that none of the other drivers use a cast here, so we can probably just do:

     struct byd_data *priv = psmouse->private;

Quoted 15 lines

drivers/input/mouse/byd.c +9 -4

+	struct input_dev *dev = psmouse->dev;
 
-	if (set_properties) {
-		psmouse->vendor = "BYD";
-		psmouse->name = "TouchPad";
-	}
+	input_report_abs(dev, ABS_X, priv->abs_x);
+	input_report_abs(dev, ABS_Y, priv->abs_y);
+	input_report_key(dev, BTN_LEFT, priv->btn_left);
+	input_report_key(dev, BTN_RIGHT, priv->btn_right);
+	input_report_key(dev, BTN_TOUCH, priv->touch);
+	input_report_key(dev, BTN_TOOL_FINGER, priv->touch);
+	input_sync(dev);
+}

drivers/input/mouse/byd.c

Quoted 4 lines

drivers/input/mouse/byd.c +3 -1

-	return 0;
+static void byd_clear_touch(unsigned long data)
+{
+	struct psmouse *psmouse = (struct psmouse *) data;

See previous comment.

Quoted 57 lines

drivers/input/mouse/byd.c +29 -13

+	struct byd_data *priv = psmouse->private;
+
+	serio_pause_rx(psmouse->ps2dev.serio);
+	priv->touch = false;
+	/*
+	 * Move cursor back to center of pad when we lose touch - this
+	 * specifically improves user experience when moving cursor with one
+	 * finger, and pressing a button with another.
+	 */
+	priv->abs_x = BYD_CONST_PAD_WIDTH / 2;
+	priv->abs_y = BYD_CONST_PAD_HEIGHT / 2;
+	byd_report_input(psmouse);
+
+	serio_continue_rx(psmouse->ps2dev.serio);
  }
 
  static psmouse_ret_t byd_process_byte(struct psmouse *psmouse)
  {
-	struct input_dev *dev = psmouse->dev;
+	struct byd_data *priv = psmouse->private;
+	u32 now_msecs = jiffies_to_msecs(jiffies);
  	u8 *pkt = psmouse->packet;
 
  	if (psmouse->pktcnt > 0 && !(pkt[0] & PS2_ALWAYS_1)) {

@@ -102,53 +285,37 @@ static psmouse_ret_t byd_process_byte(struct psmouse
 *psmouse)
 
  	/* Otherwise, a full packet has been received */
  	switch (pkt[3]) {
-	case 0: {
+	case BYD_PACKET_ABSOLUTE:
+		/* Only use absolute packets for the start of movement. */
+		if (!priv->touch) {
+			priv->abs_x = pkt[1] * (BYD_CONST_PAD_WIDTH / 256);
+			priv->abs_y = (255 - pkt[2]) *
+				      (BYD_CONST_PAD_HEIGHT / 256);
+
+			/* needed to detect tap */
+			if (now_msecs - priv->last_touch_time > 64)
+				priv->touch = true;
+		}
+		break;
+	case BYD_PACKET_RELATIVE: {
  		/* Standard packet */
  		/* Sign-extend if a sign bit is set. */
-		unsigned int signx = pkt[0] & PS2_X_SIGN ? ~0xFF : 0;
-		unsigned int signy = pkt[0] & PS2_Y_SIGN ? ~0xFF : 0;
-		int dx = signx | (int) pkt[1];
-		int dy = signy | (int) pkt[2];
-
-		input_report_rel(psmouse->dev, REL_X, dx);
-		input_report_rel(psmouse->dev, REL_Y, -dy);
-
-		input_report_key(psmouse->dev, BTN_LEFT, pkt[0] & PS2_LEFT);
-		input_report_key(psmouse->dev, BTN_RIGHT, pkt[0] & PS2_RIGHT);
-		input_report_key(psmouse->dev, BTN_MIDDLE, pkt[0] & PS2_MIDDLE);

drivers/input/mouse/byd.c static psmouse_ret_t byd_process_byte(struct psmouse · line 307

Quoted 4 lines

drivers/input/mouse/byd.c +4 -0

+		u32 signx = pkt[0] & PS2_X_SIGN ? ~0xFF : 0;
+		u32 signy = pkt[0] & PS2_Y_SIGN ? ~0xFF : 0;
+		s32 dx = signx | (int) pkt[1];
+		s32 dy = signy | (int) pkt[2];

This bit (replacing int/unsigned int with u32/s32) doesn't actually need to change, the logic doesn't depend on a particular type width. (the draft patch I sent you had it as an experiment...).

drivers/input/mouse/byd.c static psmouse_ret_t byd_process_byte(struct psmouse · line 315

Quoted 9 lines

drivers/input/mouse/byd.c +8 -0

+
+		/*
+		 * Experiments show relative mouse packets come in increments
+		 * of 1 unit / 11 milliseconds (regardless of time delta between
+		 * relative packets).
+		 */
+		priv->abs_x += dx * 11;
+		priv->abs_y -= dy * 11;

What do you mean by "1 unit / 11 ms"? Do you mean that relative packets arrive every 11 ms? Except saying "regardless of time delta" implies the opposite.

Also it might be worth putting replacing "11" with a #define.

Quoted 132 lines

drivers/input/mouse/byd.c +2 -31

+
+		priv->touch = true;
  		break;
  	}
-
-	case BYD_SCROLLDOWN:
-	case BYD_2DOWN:
-		input_report_rel(dev, REL_WHEEL, -1);
-		break;
-
-	case BYD_SCROLLUP:
-	case BYD_2UP:
-		input_report_rel(dev, REL_WHEEL, 1);
-		break;
-
-	case BYD_SCROLLLEFT:
-	case BYD_2LEFT:
-		input_report_rel(dev, REL_HWHEEL, -1);
-		break;
-
-	case BYD_SCROLLRIGHT:
-	case BYD_2RIGHT:
-		input_report_rel(dev, REL_HWHEEL, 1);
-		break;
-
-	case BYD_ZOOMOUT:
-	case BYD_ZOOMIN:
-	case BYD_3UP:
-	case BYD_3DOWN:
-	case BYD_3LEFT:
-	case BYD_3RIGHT:
-	case BYD_4UP:
-	case BYD_4DOWN:
-		break;
-
  	default:
  		psmouse_warn(psmouse,

"Unrecognized Z: pkt = %02x %02x %02x %02x\n",

drivers/input/mouse/byd.c +8 -72

@@ -157,134 +324,76 @@ static psmouse_ret_t byd_process_byte(struct psmouse
 *psmouse)
  		return PSMOUSE_BAD_DATA;
  	}
 
-	input_sync(dev);
+	priv->btn_left = pkt[0] & PS2_LEFT;
+	priv->btn_right = pkt[0] & PS2_RIGHT;
 
-	return PSMOUSE_FULL_PACKET;
-}
+	byd_report_input(psmouse);
 
-/* Send a sequence of bytes, where each is ACKed before the next is sent.
 */
-static int byd_send_sequence(struct psmouse *psmouse, const u8 *seq, size_t
 len)
-{
-	unsigned int i;
-
-	for (i = 0; i < len; ++i) {
-		if (ps2_command(&psmouse->ps2dev, NULL, seq[i]))
-			return -1;
+	/* Reset time since last touch. */
+	if (priv->touch) {
+		priv->last_touch_time = now_msecs;
+		mod_timer(&priv->timer, jiffies + msecs_to_jiffies(64));
  	}
-	return 0;
-}
-
-/* Keep scrolling after fingers are removed. */
-#define SCROLL_INERTIAL		0x01
-#define SCROLL_NO_INERTIAL	0x02
-
-/* Clicking can be done by tapping or pressing. */
-#define CLICK_BOTH		0x01
-/* Clicking can only be done by pressing. */
-#define CLICK_PRESS_ONLY	0x02
-
-static int byd_enable(struct psmouse *psmouse)
-{
-	const u8 seq1[] = { 0xE2, 0x00, 0xE0, 0x02, 0xE0 };
-	const u8 seq2[] = {
-		0xD3, 0x01,
-		0xD0, 0x00,
-		0xD0, 0x04,
-		/* Whether clicking is done by tapping or pressing. */
-		0xD4, CLICK_PRESS_ONLY,
-		0xD5, 0x01,
-		0xD7, 0x03,
-		/* Vertical and horizontal one-finger scroll zone inertia. */
-		0xD8, SCROLL_INERTIAL,
-		0xDA, 0x05,
-		0xDB, 0x02,
-		0xE4, 0x05,
-		0xD6, 0x01,
-		0xDE, 0x04,
-		0xE3, 0x01,
-		0xCF, 0x00,
-		0xD2, 0x03,
-		/* Vertical and horizontal two-finger scrolling inertia. */
-		0xE5, SCROLL_INERTIAL,
-		0xD9, 0x02,
-		0xD9, 0x07,
-		0xDC, 0x03,
-		0xDD, 0x03,
-		0xDF, 0x03,
-		0xE1, 0x03,
-		0xD1, 0x00,
-		0xCE, 0x00,
-		0xCC, 0x00,
-		0xE0, 0x00,
-		0xE2, 0x01
-	};
-	u8 param[4];
-
-	if (byd_send_sequence(psmouse, seq1, ARRAY_SIZE(seq1)))
-		return -1;
-
-	/* Send a 0x01 command, which should return 4 bytes. */
-	if (ps2_command(&psmouse->ps2dev, param, 0x0401))
-		return -1;
 
-	if (byd_send_sequence(psmouse, seq2, ARRAY_SIZE(seq2)))
-		return -1;
-
-	return 0;
+	return PSMOUSE_FULL_PACKET;
  }
 
-/*
- * Send the set of PS/2 commands required to make it identify as an

drivers/input/mouse/byd.c static psmouse_ret_t byd_process_byte(struct psmouse · line 349

Quoted 10 lines

drivers/input/mouse/byd.c +3 -4

- * intellimouse with 4-byte instead of 3-byte packets.
- */
-static int byd_send_intellimouse_sequence(struct psmouse *psmouse)
+static int byd_reset_touchpad(struct psmouse *psmouse)
  {
  	struct ps2dev *ps2dev = &psmouse->ps2dev;
  	u8 param[4];
-	int i;
+	size_t i;
+

Good point.

Quoted 186 lines

drivers/input/mouse/byd.c +36 -29

  	const struct {
  		u16 command;
  		u8 arg;
  	} seq[] = {
-		{ PSMOUSE_CMD_RESET_BAT, 0 },
-		{ PSMOUSE_CMD_RESET_BAT, 0 },
-		{ PSMOUSE_CMD_GETID, 0 },
-		{ PSMOUSE_CMD_SETSCALE11, 0 },
-		{ PSMOUSE_CMD_SETSCALE11, 0 },
-		{ PSMOUSE_CMD_SETSCALE11, 0 },
-		{ PSMOUSE_CMD_GETINFO, 0 },
-		{ PSMOUSE_CMD_SETRES, 0x03 },
+		/*
+		 * Intellimouse initialization sequence, to get 4-byte instead
+		 * of 3-byte packets.
+		 */
  		{ PSMOUSE_CMD_SETRATE, 0xC8 },
  		{ PSMOUSE_CMD_SETRATE, 0x64 },
  		{ PSMOUSE_CMD_SETRATE, 0x50 },
  		{ PSMOUSE_CMD_GETID, 0 },
-		{ PSMOUSE_CMD_SETRATE, 0xC8 },
-		{ PSMOUSE_CMD_SETRATE, 0xC8 },
-		{ PSMOUSE_CMD_SETRATE, 0x50 },
-		{ PSMOUSE_CMD_GETID, 0 },
-		{ PSMOUSE_CMD_SETRATE, 0x64 },
-		{ PSMOUSE_CMD_SETRES, 0x03 },
-		{ PSMOUSE_CMD_ENABLE, 0 }
+		{ PSMOUSE_CMD_ENABLE, 0 },
+		/*
+		 * BYD-specific initialization, which enables absolute mode and
+		 * (if desired), the touchpad's built-in gesture detection.
+		 */
+		{ 0x10E2, 0x00 },
+		{ 0x10E0, 0x02 },
+		/* The touchpad should reply with 4 seemingly-random bytes */
+		{ 0x14E0, 0x01 },
+		/* Pairs of parameters and values. */
+		{ BYD_CMD_SET_HANDEDNESS, 0x01 },
+		{ BYD_CMD_SET_PHYSICAL_BUTTONS, 0x04 },
+		{ BYD_CMD_SET_TAP, 0x02 },
+		{ BYD_CMD_SET_ONE_FINGER_SCROLL, 0x04 },
+		{ BYD_CMD_SET_ONE_FINGER_SCROLL_FUNC, 0x04 },
+		{ BYD_CMD_SET_EDGE_MOTION, 0x01 },
+		{ BYD_CMD_SET_PALM_CHECK, 0x00 },
+		{ BYD_CMD_SET_MULTITOUCH, 0x02 },
+		{ BYD_CMD_SET_TWO_FINGER_SCROLL, 0x04 },
+		{ BYD_CMD_SET_TWO_FINGER_SCROLL_FUNC, 0x04 },
+		{ BYD_CMD_SET_LEFT_EDGE_REGION, 0x00 },
+		{ BYD_CMD_SET_TOP_EDGE_REGION, 0x00 },
+		{ BYD_CMD_SET_RIGHT_EDGE_REGION, 0x00 },
+		{ BYD_CMD_SET_BOTTOM_EDGE_REGION, 0x00 },
+		{ BYD_CMD_SET_ABSOLUTE_MODE, 0x02 },
+		/* Finalize initialization. */
+		{ 0x10E0, 0x00 },
+		{ 0x10E2, 0x01 },
  	};
 
-	memset(param, 0, sizeof(param));
  	for (i = 0; i < ARRAY_SIZE(seq); ++i) {
+		memset(param, 0, sizeof(param));
  		param[0] = seq[i].arg;
  		if (ps2_command(ps2dev, param, seq[i].command))
-			return -1;
-	}
-
-	return 0;
-}
-
-static int byd_reset_touchpad(struct psmouse *psmouse)
-{
-	if (byd_send_intellimouse_sequence(psmouse))
-		return -EIO;
-
-	if (byd_enable(psmouse))
-		return -EIO;
+			return -EIO;
 
+	}
+	psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);

  	return 0;
  }

drivers/input/mouse/byd.c +69 -3

@@ -314,9 +423,50 @@ static int byd_reconnect(struct psmouse *psmouse)
  	return 0;
  }
 
+static void byd_disconnect(struct psmouse *psmouse)
+{
+	struct byd_data *priv = psmouse->private;
+
+	if (priv) {
+		del_timer(&priv->timer);
+		kfree(psmouse->private);
+		psmouse->private = NULL;
+	}
+}
+
+int byd_detect(struct psmouse *psmouse, bool set_properties)
+{
+	struct ps2dev *ps2dev = &psmouse->ps2dev;
+	u8 param[4] = {0x03, 0x00, 0x00, 0x00};
+
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+		return -1;
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+		return -1;
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+		return -1;
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
+		return -1;
+	if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
+		return -1;
+
+	if (param[1] != 0x03 || param[2] != 0x64)
+		return -ENODEV;
+
+	psmouse_dbg(psmouse, "BYD touchpad detected\n");
+
+	if (set_properties) {
+		psmouse->vendor = "BYD";
+		psmouse->name = "TouchPad";
+	}
+
+	return 0;
+}
+
  int byd_init(struct psmouse *psmouse)
  {
  	struct input_dev *dev = psmouse->dev;
+	struct byd_data *priv;
 
  	if (psmouse_reset(psmouse))
  		return -EIO;

@@ -324,14 +474,39 @@ int byd_init(struct psmouse *psmouse)
  	if (byd_reset_touchpad(psmouse))
  		return -EIO;
 
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	memset(priv, 0, sizeof(*priv));
+	setup_timer(&priv->timer, byd_clear_touch, (unsigned long) psmouse);
+
+	psmouse->private = priv;
+	psmouse->disconnect = byd_disconnect;
  	psmouse->reconnect = byd_reconnect;
  	psmouse->protocol_handler = byd_process_byte;
  	psmouse->pktsize = 4;
  	psmouse->resync_time = 0;
 
-	__set_bit(BTN_MIDDLE, dev->keybit);
-	__set_bit(REL_WHEEL, dev->relbit);
-	__set_bit(REL_HWHEEL, dev->relbit);
+	__set_bit(INPUT_PROP_POINTER, dev->propbit);
+	/* Touchpad */
+	__set_bit(BTN_TOUCH, dev->keybit);
+	__set_bit(BTN_TOOL_FINGER, dev->keybit);
+	/* Buttons */
+	__set_bit(BTN_LEFT, dev->keybit);
+	__set_bit(BTN_RIGHT, dev->keybit);
+	__clear_bit(BTN_MIDDLE, dev->keybit);
+
+	/* Absolute position */
+	__set_bit(EV_ABS, dev->evbit);
+	input_set_abs_params(dev, ABS_X, 0, BYD_CONST_PAD_WIDTH, 0, 0);
+	input_set_abs_params(dev, ABS_Y, 0, BYD_CONST_PAD_HEIGHT, 0, 0);
+	input_abs_set_res(dev, ABS_X, BYD_CONST_PAD_RESOLUTION);
+	input_abs_set_res(dev, ABS_Y, BYD_CONST_PAD_RESOLUTION);
+	/* No relative support */
+	__clear_bit(EV_REL, dev->evbit);
+	__clear_bit(REL_X, dev->relbit);
+	__clear_bit(REL_Y, dev->relbit);
 
  	return 0;
  }

drivers/input/mouse/psmouse-base.c +0 -0

index 39d1bec..5784e20 100644
@@ -846,7 +846,7 @@ static const struct psmouse_protocol psmouse_protocols[]
 = {
  #ifdef CONFIG_MOUSE_PS2_BYD
  	{
  		.type		= PSMOUSE_BYD,