HID: lenovo: Add middleclick_workaround sysfs knob for cptkbd

PATCH In review Mikhail Khvainitski 5 participants 16 messages Sep 18, 2023 – Jan 23, 2024

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HID Lenovo HID drivers

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Mikhail Khvainitski

author

2023-09-18 16:03 UTC #0 lore raw

PATCH 1/1 HID: lenovo: Add middleclick_workaround sysfs knob for cptkbd

Built-in firmware of cptkbd handles scrolling by itself (when middle button is pressed) but with issues: it does not support horizontal and hi-res scrolling and upon middle button release it sends middle button click even if there was a scrolling event. Commit 3cb5ff0220e3 ("HID:
lenovo: Hide middle-button press until release") workarounds last issue but it's impossible to workaround scrolling-related issues without firmware modification.

Likely, Dennis Schneider has reverse engineered the firmware and provided an instruction on how to patch it [1]. However, aforementioned workaround prevents userspace (libinput) from knowing exact moment when middle button has been pressed down and performing "On-Button scrolling". This commit makes it possible to disable this workaround by sysfs knob.

Link https://hohlerde.org/rauch/en/elektronik/projekte/tpkbd-fix/ [1]

Signed-off-by Mikhail Khvainitski <[email protected]>

---
 drivers/hid/hid-lenovo.c | 84 +++++++++++++++++++++++++++++-----------
 1 file changed, 62 insertions(+), 22 deletions(-)

drivers/hid/hid-lenovo.c +62 ~~-22~~

index 44763c0da444..8993fa1ce66a 100644
@@ -53,6 +53,7 @@ struct lenovo_drvdata {
 	int press_speed;
 	u8 middlebutton_state; /* 0:Up, 1:Down (undecided), 2:Scrolling */
 	bool fn_lock;
+	bool middleclick_workaround_cptkbd;
 };
 
 #define map_key_clear(c) hid_map_usage_clear(hi, usage, bit, max, EV_KEY, (c))

@@ -603,6 +604,36 @@ static ssize_t attr_sensitivity_store_cptkbd(struct device *dev,
 	return count;
 }
 
+static ssize_t attr_middleclick_workaround_show_cptkbd(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct hid_device *hdev = to_hid_device(dev);
+	struct lenovo_drvdata *cptkbd_data = hid_get_drvdata(hdev);
+
+	return snprintf(buf, PAGE_SIZE, "%u\n",
+		cptkbd_data->middleclick_workaround_cptkbd);
+}
+
+static ssize_t attr_middleclick_workaround_store_cptkbd(struct device *dev,
+		struct device_attribute *attr,
+		const char *buf,
+		size_t count)
+{
+	struct hid_device *hdev = to_hid_device(dev);
+	struct lenovo_drvdata *cptkbd_data = hid_get_drvdata(hdev);
+	int value;
+
+	if (kstrtoint(buf, 10, &value))
+		return -EINVAL;
+	if (value < 0 || value > 1)
+		return -EINVAL;
+
+	cptkbd_data->middleclick_workaround_cptkbd = !!value;
+
+	return count;
+}
+
 
 static struct device_attribute dev_attr_fn_lock =
 	__ATTR(fn_lock, S_IWUSR | S_IRUGO,

@@ -614,10 +645,16 @@ static struct device_attribute dev_attr_sensitivity_cptkbd =
 			attr_sensitivity_show_cptkbd,
 			attr_sensitivity_store_cptkbd);
 
+static struct device_attribute dev_attr_middleclick_workaround_cptkbd =
+	__ATTR(middleclick_workaround, S_IWUSR | S_IRUGO,
+			attr_middleclick_workaround_show_cptkbd,
+			attr_middleclick_workaround_store_cptkbd);
+
 
 static struct attribute *lenovo_attributes_cptkbd[] = {
 	&dev_attr_fn_lock.attr,
 	&dev_attr_sensitivity_cptkbd.attr,
+	&dev_attr_middleclick_workaround_cptkbd.attr,
 	NULL
 };

@@ -668,31 +705,33 @@ static int lenovo_event_cptkbd(struct hid_device *hdev,
 {
 	struct lenovo_drvdata *cptkbd_data = hid_get_drvdata(hdev);
 
-	/* "wheel" scroll events */
-	if (usage->type == EV_REL && (usage->code == REL_WHEEL ||
-			usage->code == REL_HWHEEL)) {
-		/* Scroll events disable middle-click event */
-		cptkbd_data->middlebutton_state = 2;
-		return 0;
-	}
+	if (cptkbd_data->middleclick_workaround_cptkbd) {
+		/* "wheel" scroll events */
+		if (usage->type == EV_REL && (usage->code == REL_WHEEL ||
+				usage->code == REL_HWHEEL)) {
+			/* Scroll events disable middle-click event */
+			cptkbd_data->middlebutton_state = 2;
+			return 0;
+		}
 
-	/* Middle click events */
-	if (usage->type == EV_KEY && usage->code == BTN_MIDDLE) {
-		if (value == 1) {
-			cptkbd_data->middlebutton_state = 1;
-		} else if (value == 0) {
-			if (cptkbd_data->middlebutton_state == 1) {
-				/* No scrolling inbetween, send middle-click */
-				input_event(field->hidinput->input,
-					EV_KEY, BTN_MIDDLE, 1);
-				input_sync(field->hidinput->input);
-				input_event(field->hidinput->input,
-					EV_KEY, BTN_MIDDLE, 0);
-				input_sync(field->hidinput->input);
+		/* Middle click events */
+		if (usage->type == EV_KEY && usage->code == BTN_MIDDLE) {
+			if (value == 1) {
+				cptkbd_data->middlebutton_state = 1;
+			} else if (value == 0) {
+				if (cptkbd_data->middlebutton_state == 1) {
+					/* No scrolling inbetween, send middle-click */
+					input_event(field->hidinput->input,
+						EV_KEY, BTN_MIDDLE, 1);
+					input_sync(field->hidinput->input);
+					input_event(field->hidinput->input,
+						EV_KEY, BTN_MIDDLE, 0);
+					input_sync(field->hidinput->input);
+				}
+				cptkbd_data->middlebutton_state = 0;
 			}
-			cptkbd_data->middlebutton_state = 0;
+			return 1;
 		}
-		return 1;
 	}
 
 	if (usage->type == EV_KEY && usage->code == KEY_FN_ESC && value == 1) {

@@ -1146,6 +1185,7 @@ static int lenovo_probe_cptkbd(struct hid_device *hdev)
 	cptkbd_data->middlebutton_state = 0;
 	cptkbd_data->fn_lock = true;
 	cptkbd_data->sensitivity = 0x05;
+	cptkbd_data->middleclick_workaround_cptkbd = true;
 	lenovo_features_set_cptkbd(hdev);
 
 	ret = sysfs_create_group(&hdev->dev.kobj, &lenovo_attr_group_cptkbd);

Signature · 1 line

2.42.0

Mikhail Khvainitski

author

2023-09-23 23:21 UTC #1 lore raw

So, while I was waiting for the review of the patch, I've come up with much better idea: we can just autodetect if stock and buggy or patched and bug-free firmware is used and have no need to introduce additional sysfs knob. So the patch which implements this follows in the next message.

While the patch is ready to be merged as is (of course, if there are no comments from reviewers), I thought about the following: may be we should add a message to dmesg upon detecting stock and buggy firmware that user should consider patching the firmware? If so, what is the best place to put an instruction to? Post a link to dmesg? Can the link point directly to Dennis' blog or its better to put it somewhere else (with credits, of course)?

Thanks.

Mikhail Khvainitski

author

2023-09-23 23:15 UTC #2 lore raw

PATCH 1/1 HID: lenovo: Detect quirk-free fw on cptkbd and stop applying workaround

Likely, Dennis Schneider has reverse engineered the firmware and provided an instruction on how to patch it [1]. However, aforementioned workaround prevents userspace (libinput) from knowing exact moment when middle button has been pressed down and performing "On-Button scrolling". This commit detects correctly-behaving patched firmware if cursor movement events has been received during middle button being pressed and stops applying workaround for this device.

Link https://hohlerde.org/rauch/en/elektronik/projekte/tpkbd-fix/ [1]

Signed-off-by Mikhail Khvainitski <[email protected]>

---
 drivers/hid/hid-lenovo.c | 68 ++++++++++++++++++++++++++--------------
 1 file changed, 45 insertions(+), 23 deletions(-)

drivers/hid/hid-lenovo.c +45 ~~-23~~

index 44763c0da444..9c1181313e44 100644
@@ -51,7 +51,12 @@ struct lenovo_drvdata {
 	int select_right;
 	int sensitivity;
 	int press_speed;
-	u8 middlebutton_state; /* 0:Up, 1:Down (undecided), 2:Scrolling */
+	/* 0: Up
+	 * 1: Down (undecided)
+	 * 2: Scrolling
+	 * 3: Patched firmware, disable workaround
+	 */
+	u8 middlebutton_state;
 	bool fn_lock;
 };

@@ -668,31 +673,48 @@ static int lenovo_event_cptkbd(struct hid_device *hdev,
 {
 	struct lenovo_drvdata *cptkbd_data = hid_get_drvdata(hdev);
 
-	/* "wheel" scroll events */
-	if (usage->type == EV_REL && (usage->code == REL_WHEEL ||
-			usage->code == REL_HWHEEL)) {
-		/* Scroll events disable middle-click event */
-		cptkbd_data->middlebutton_state = 2;
-		return 0;
-	}
+	if (cptkbd_data->middlebutton_state != 3) {
+		/* REL_X and REL_Y events during middle button pressed
+		 * are only possible on patched, bug-free firmware
+		 * so set middlebutton_state to 3
+		 * to never apply workaround anymore
+		 */
+		if (cptkbd_data->middlebutton_state == 1 &&
+				usage->type == EV_REL &&
+				(usage->code == REL_X || usage->code == REL_Y)) {
+			cptkbd_data->middlebutton_state = 3;
+			/* send middle button press which was hold before */
+			input_event(field->hidinput->input,
+				EV_KEY, BTN_MIDDLE, 1);
+			input_sync(field->hidinput->input);
+		}
 
-	/* Middle click events */
-	if (usage->type == EV_KEY && usage->code == BTN_MIDDLE) {
-		if (value == 1) {
-			cptkbd_data->middlebutton_state = 1;
-		} else if (value == 0) {
-			if (cptkbd_data->middlebutton_state == 1) {
-				/* No scrolling inbetween, send middle-click */
-				input_event(field->hidinput->input,
-					EV_KEY, BTN_MIDDLE, 1);
-				input_sync(field->hidinput->input);
-				input_event(field->hidinput->input,
-					EV_KEY, BTN_MIDDLE, 0);
-				input_sync(field->hidinput->input);
+		/* "wheel" scroll events */
+		if (usage->type == EV_REL && (usage->code == REL_WHEEL ||
+				usage->code == REL_HWHEEL)) {
+			/* Scroll events disable middle-click event */
+			cptkbd_data->middlebutton_state = 2;
+			return 0;
+		}
+
+		/* Middle click events */
+		if (usage->type == EV_KEY && usage->code == BTN_MIDDLE) {
+			if (value == 1) {
+				cptkbd_data->middlebutton_state = 1;
+			} else if (value == 0) {
+				if (cptkbd_data->middlebutton_state == 1) {
+					/* No scrolling inbetween, send middle-click */
+					input_event(field->hidinput->input,
+						EV_KEY, BTN_MIDDLE, 1);
+					input_sync(field->hidinput->input);
+					input_event(field->hidinput->input,
+						EV_KEY, BTN_MIDDLE, 0);
+					input_sync(field->hidinput->input);
+				}
+				cptkbd_data->middlebutton_state = 0;
 			}
-			cptkbd_data->middlebutton_state = 0;
+			return 1;
 		}
-		return 1;
 	}
 
 	if (usage->type == EV_KEY && usage->code == KEY_FN_ESC && value == 1) {

Signature · 1 line

2.42.0

Jiri Kosina

maintainer Applied

2023-10-04 19:07 UTC #3 lore raw

Re: [PATCH] HID: lenovo: Detect quirk-free fw on cptkbd and stop applying workaround

Quoted 16 lines · Mikhail Khvainitski

Built-in firmware of cptkbd handles scrolling by itself (when middle button is pressed) but with issues: it does not support horizontal and hi-res scrolling and upon middle button release it sends middle button click even if there was a scrolling event. Commit 3cb5ff0220e3 ("HID:
lenovo: Hide middle-button press until release") workarounds last issue but it's impossible to workaround scrolling-related issues without firmware modification.
Likely, Dennis Schneider has reverse engineered the firmware and provided an instruction on how to patch it [1]. However, aforementioned workaround prevents userspace (libinput) from knowing exact moment when middle button has been pressed down and performing "On-Button scrolling". This commit detects correctly-behaving patched firmware if cursor movement events has been received during middle button being pressed and stops applying workaround for this device.

Quoted 3 lines

Link https://hohlerde.org/rauch/en/elektronik/projekte/tpkbd-fix/ [1]
Signed-off-by Mikhail Khvainitski <[email protected]>

Applied to for-6.7/lenovo, thanks.

Signature · 2 lines

Jiri Kosina
SUSE Labs

Yauhen Kharuzhy

2023-12-09 12:50 UTC #4 lore raw

Re: [PATCH] HID: lenovo: Detect quirk-free fw on cptkbd and stop applying workaround

In reply to Mikhail Khvainitski

Quoted 16 lines · Mikhail Khvainitski

Built-in firmware of cptkbd handles scrolling by itself (when middle button is pressed) but with issues: it does not support horizontal and hi-res scrolling and upon middle button release it sends middle button click even if there was a scrolling event. Commit 3cb5ff0220e3 ("HID:
lenovo: Hide middle-button press until release") workarounds last issue but it's impossible to workaround scrolling-related issues without firmware modification.
Likely, Dennis Schneider has reverse engineered the firmware and provided an instruction on how to patch it [1]. However, aforementioned workaround prevents userspace (libinput) from knowing exact moment when middle button has been pressed down and performing "On-Button scrolling". This commit detects correctly-behaving patched firmware if cursor movement events has been received during middle button being pressed and stops applying workaround for this device.

Quoted 1 line

Link https://hohlerde.org/rauch/en/elektronik/projekte/tpkbd-fix/ [1]

This patch breaks a scrolling at my ThinkPad TrackPoint Keyboard II: it starts to report middle-button push/release events with scrolling events between. A support for this keyboard was added in 24401f291dcc4f2c18b9e2f65763cbaadc7a1528 "HID: lenovo: Add support for ThinkPad TrackPoint Keyboard II" commit.

There is an evtest output below:

Without of commit:

Middle-button click:
Event: time 1702122290.593300, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702122290.593300, -------------- SYN_REPORT ------------
Event: time 1702122290.593312, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702122290.593312, -------------- SYN_REPORT ------------

Vertical scrolling:
Event: time 1702122300.441627, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702122300.441627, -------------- SYN_REPORT ------------
Event: time 1702122300.565663, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702122300.565663, -------------- SYN_REPORT ------------

Horizontal scrolling:
Event: time 1702122307.845969, type 2 (EV_REL), code 6 (REL_HWHEEL), value -1
Event: time 1702122307.845969, -------------- SYN_REPORT ------------
Event: time 1702122307.981954, type 2 (EV_REL), code 6 (REL_HWHEEL), value -1
Event: time 1702122307.981954, -------------- SYN_REPORT ------------

After commit:

Middle-button click:
Event: time 1702125091.290045, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125091.290045, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702125091.290045, -------------- SYN_REPORT ------------
Event: time 1702125092.626118, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125092.626118, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702125092.626118, -------------- SYN_REPORT ------------

Vscroll:
Event: time 1702125286.653639, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125286.653639, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702125286.653639, -------------- SYN_REPORT ------------
Event: time 1702125287.929689, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702125287.929689, -------------- SYN_REPORT ------------
Event: time 1702125288.037688, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702125288.037688, -------------- SYN_REPORT ------------
Event: time 1702125290.481787, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125290.481787, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702125290.481787, -------------- SYN_REPORT ------------

Hscroll:
Event: time 1702125293.841920, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125293.841920, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702125293.841920, -------------- SYN_REPORT ------------
Event: time 1702125294.761952, type 2 (EV_REL), code 6 (REL_HWHEEL), value -1
Event: time 1702125294.761952, -------------- SYN_REPORT ------------
Event: time 1702125294.893967, type 2 (EV_REL), code 6 (REL_HWHEEL), value -1
Event: time 1702125294.893967, -------------- SYN_REPORT ------------
Event: time 1702125296.134006, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125296.134006, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702125296.134006, -------------- SYN_REPORT ------------

Signature · 1 line

Yauhen Kharuzhy

Yauhen Kharuzhy

2023-12-09 16:56 UTC #5 lore raw

Re: [PATCH] HID: lenovo: Detect quirk-free fw on cptkbd and stop applying workaround

Quoted 17 lines · Yauhen Kharuzhy

Quoted 16 lines · Mikhail Khvainitski
Built-in firmware of cptkbd handles scrolling by itself (when middle button is pressed) but with issues: it does not support horizontal and hi-res scrolling and upon middle button release it sends middle button click even if there was a scrolling event. Commit 3cb5ff0220e3 ("HID:
lenovo: Hide middle-button press until release") workarounds last issue but it's impossible to workaround scrolling-related issues without firmware modification.
Likely, Dennis Schneider has reverse engineered the firmware and provided an instruction on how to patch it [1]. However, aforementioned workaround prevents userspace (libinput) from knowing exact moment when middle button has been pressed down and performing "On-Button scrolling". This commit detects correctly-behaving patched firmware if cursor movement events has been received during middle button being pressed and stops applying workaround for this device.

Quoted 7 lines

Quoted 1 line
Link https://hohlerde.org/rauch/en/elektronik/projekte/tpkbd-fix/ [1]
This patch breaks a scrolling at my ThinkPad TrackPoint Keyboard II: it starts to report middle-button push/release events with scrolling events between. A support for this keyboard was added in 24401f291dcc4f2c18b9e2f65763cbaadc7a1528 "HID: lenovo: Add support for ThinkPad TrackPoint Keyboard II" commit.

I figured this out.

This keyboard can emit REL_Y/REL_X events between of middle-button events (if user was moving a cursor and press middle button without of stopping this), so this algorithm does a false-positive detection and switches the workaround off like for patched firmware:

Event: time 1702140625.854777, type 2 (EV_REL), code 1 (REL_Y), value 2
Event: time 1702140625.854777, -------------- SYN_REPORT ------------
Event: time 1702140625.870769, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702140625.870769, -------------- SYN_REPORT ------------
Event: time 1702140625.870771, type 2 (EV_REL), code 1 (REL_Y), value 2
Event: time 1702140625.870771, -------------- SYN_REPORT ------------
Event: time 1702140625.970780, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702140625.970780, -------------- SYN_REPORT ------------
Event: time 1702140626.058800, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702140626.058800, -------------- SYN_REPORT ------------
Event: time 1702140630.462974, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702140630.462974, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702140630.462974, -------------- SYN_REPORT ------------

Quoted 59 lines

There is an evtest output below:
Without of commit:
Middle-button click:
Event: time 1702122290.593300, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702122290.593300, -------------- SYN_REPORT ------------
Event: time 1702122290.593312, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702122290.593312, -------------- SYN_REPORT ------------
Vertical scrolling:
Event: time 1702122300.441627, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702122300.441627, -------------- SYN_REPORT ------------
Event: time 1702122300.565663, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702122300.565663, -------------- SYN_REPORT ------------
Horizontal scrolling:
Event: time 1702122307.845969, type 2 (EV_REL), code 6 (REL_HWHEEL), value -1
Event: time 1702122307.845969, -------------- SYN_REPORT ------------
Event: time 1702122307.981954, type 2 (EV_REL), code 6 (REL_HWHEEL), value -1
Event: time 1702122307.981954, -------------- SYN_REPORT ------------
After commit:
Middle-button click:
Event: time 1702125091.290045, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125091.290045, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702125091.290045, -------------- SYN_REPORT ------------
Event: time 1702125092.626118, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125092.626118, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702125092.626118, -------------- SYN_REPORT ------------
Vscroll:
Event: time 1702125286.653639, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125286.653639, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702125286.653639, -------------- SYN_REPORT ------------
Event: time 1702125287.929689, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702125287.929689, -------------- SYN_REPORT ------------
Event: time 1702125288.037688, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702125288.037688, -------------- SYN_REPORT ------------
Event: time 1702125290.481787, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125290.481787, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702125290.481787, -------------- SYN_REPORT ------------
Hscroll:
Event: time 1702125293.841920, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125293.841920, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702125293.841920, -------------- SYN_REPORT ------------
Event: time 1702125294.761952, type 2 (EV_REL), code 6 (REL_HWHEEL), value -1
Event: time 1702125294.761952, -------------- SYN_REPORT ------------
Event: time 1702125294.893967, type 2 (EV_REL), code 6 (REL_HWHEEL), value -1
Event: time 1702125294.893967, -------------- SYN_REPORT ------------
Event: time 1702125296.134006, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125296.134006, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702125296.134006, -------------- SYN_REPORT ------------

Signature · 1 line

Yauhen Kharuzhy

Yauhen Kharuzhy

2023-12-09 18:21 UTC #6 lore raw

Re: [PATCH] HID: lenovo: Detect quirk-free fw on cptkbd and stop applying workaround

Quoted 33 lines · Yauhen Kharuzhy

Quoted 17 lines · Yauhen Kharuzhy
Quoted 16 lines · Mikhail Khvainitski
Built-in firmware of cptkbd handles scrolling by itself (when middle button is pressed) but with issues: it does not support horizontal and hi-res scrolling and upon middle button release it sends middle button click even if there was a scrolling event. Commit 3cb5ff0220e3 ("HID:
lenovo: Hide middle-button press until release") workarounds last issue but it's impossible to workaround scrolling-related issues without firmware modification.
Likely, Dennis Schneider has reverse engineered the firmware and provided an instruction on how to patch it [1]. However, aforementioned workaround prevents userspace (libinput) from knowing exact moment when middle button has been pressed down and performing "On-Button scrolling". This commit detects correctly-behaving patched firmware if cursor movement events has been received during middle button being pressed and stops applying workaround for this device.
Quoted 7 lines
Quoted 1 line
Link https://hohlerde.org/rauch/en/elektronik/projekte/tpkbd-fix/ [1]
This patch breaks a scrolling at my ThinkPad TrackPoint Keyboard II: it starts to report middle-button push/release events with scrolling events between. A support for this keyboard was added in 24401f291dcc4f2c18b9e2f65763cbaadc7a1528 "HID: lenovo: Add support for ThinkPad TrackPoint Keyboard II" commit.
I figured this out.
This keyboard can emit REL_Y/REL_X events between of middle-button events (if user was moving a cursor and press middle button without of stopping this), so this algorithm does a false-positive detection and switches the workaround off like for patched firmware:

Quoted 13 lines

Event: time 1702140625.854777, type 2 (EV_REL), code 1 (REL_Y), value 2
Event: time 1702140625.854777, -------------- SYN_REPORT ------------
Event: time 1702140625.870769, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702140625.870769, -------------- SYN_REPORT ------------
Event: time 1702140625.870771, type 2 (EV_REL), code 1 (REL_Y), value 2
Event: time 1702140625.870771, -------------- SYN_REPORT ------------
Event: time 1702140625.970780, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702140625.970780, -------------- SYN_REPORT ------------
Event: time 1702140626.058800, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702140626.058800, -------------- SYN_REPORT ------------
Event: time 1702140630.462974, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702140630.462974, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702140630.462974, -------------- SYN_REPORT ------------

Maybe we should map the wheel HID reports to REL_Y/REL_X in lenovo_input_mapping_tpIIkbd() to allow libinput to do its wheel emulation job? I tried this but I am not familiar with HID drivers and had no success.

Quoted 64 lines

Quoted 61 lines
There is an evtest output below:
Without of commit:
Middle-button click:
Event: time 1702122290.593300, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702122290.593300, -------------- SYN_REPORT ------------
Event: time 1702122290.593312, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702122290.593312, -------------- SYN_REPORT ------------
Vertical scrolling:
Event: time 1702122300.441627, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702122300.441627, -------------- SYN_REPORT ------------
Event: time 1702122300.565663, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702122300.565663, -------------- SYN_REPORT ------------
Horizontal scrolling:
Event: time 1702122307.845969, type 2 (EV_REL), code 6 (REL_HWHEEL), value -1
Event: time 1702122307.845969, -------------- SYN_REPORT ------------
Event: time 1702122307.981954, type 2 (EV_REL), code 6 (REL_HWHEEL), value -1
Event: time 1702122307.981954, -------------- SYN_REPORT ------------
After commit:
Middle-button click:
Event: time 1702125091.290045, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125091.290045, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702125091.290045, -------------- SYN_REPORT ------------
Event: time 1702125092.626118, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125092.626118, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702125092.626118, -------------- SYN_REPORT ------------
Vscroll:
Event: time 1702125286.653639, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125286.653639, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702125286.653639, -------------- SYN_REPORT ------------
Event: time 1702125287.929689, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702125287.929689, -------------- SYN_REPORT ------------
Event: time 1702125288.037688, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702125288.037688, -------------- SYN_REPORT ------------
Event: time 1702125290.481787, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125290.481787, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702125290.481787, -------------- SYN_REPORT ------------
Hscroll:
Event: time 1702125293.841920, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125293.841920, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702125293.841920, -------------- SYN_REPORT ------------
Event: time 1702125294.761952, type 2 (EV_REL), code 6 (REL_HWHEEL), value -1
Event: time 1702125294.761952, -------------- SYN_REPORT ------------
Event: time 1702125294.893967, type 2 (EV_REL), code 6 (REL_HWHEEL), value -1
Event: time 1702125294.893967, -------------- SYN_REPORT ------------
Event: time 1702125296.134006, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125296.134006, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702125296.134006, -------------- SYN_REPORT ------------
Signature · 1 line
Yauhen Kharuzhy

Signature · 1 line

Yauhen Kharuzhy

Mikhail Khvoinitsky

author

2023-12-11 16:18 UTC #7 lore raw

Re: [PATCH] HID: lenovo: Detect quirk-free fw on cptkbd and stop applying workaround

Hello.

Well, that's unfortunate. As far as I can see, yes, TrackPoint Keyboard II behaves similarly to 1st gen Trackpoint Keyboard (a.k.a. Compact) but not quite. The best way would be to make the keyboard not emulate scrolling at all but not sure if its possible. For cptkbd it required patching firmware, it might be also the case for 2nd gen.

Quoted 2 lines

Maybe we should map the wheel HID reports to REL_Y/REL_X in lenovo_input_mapping_tpIIkbd() to allow libinput to do its wheel emulation job?

It might work but since emulated wheel events aren't continuous (at least this is the case with cptkbd), it doesn't make much sense in comparison with the original implementation — just ignore the middle button if scrolling.

I'll try to get the keyboard and check, but at the moment it seems that the best thing to do is before stopping applying a workaround, check that it's a Trackpoint Compact keyboard, not anything else. If I won't be able to find a better solution shortly, I'll make a patch which makes sure that it's only cptkbd before disabling the workaround.

Quoted 121 lines · Yauhen Kharuzhy

Quoted 33 lines · Yauhen Kharuzhy
Quoted 17 lines · Yauhen Kharuzhy
Quoted 16 lines · Mikhail Khvainitski
Built-in firmware of cptkbd handles scrolling by itself (when middle button is pressed) but with issues: it does not support horizontal and hi-res scrolling and upon middle button release it sends middle button click even if there was a scrolling event. Commit 3cb5ff0220e3 ("HID:
lenovo: Hide middle-button press until release") workarounds last issue but it's impossible to workaround scrolling-related issues without firmware modification.
Likely, Dennis Schneider has reverse engineered the firmware and provided an instruction on how to patch it [1]. However, aforementioned workaround prevents userspace (libinput) from knowing exact moment when middle button has been pressed down and performing "On-Button scrolling". This commit detects correctly-behaving patched firmware if cursor movement events has been received during middle button being pressed and stops applying workaround for this device.
Quoted 7 lines
Quoted 1 line
Link https://hohlerde.org/rauch/en/elektronik/projekte/tpkbd-fix/ [1]
This patch breaks a scrolling at my ThinkPad TrackPoint Keyboard II: it starts to report middle-button push/release events with scrolling events between. A support for this keyboard was added in 24401f291dcc4f2c18b9e2f65763cbaadc7a1528 "HID: lenovo: Add support for ThinkPad TrackPoint Keyboard II" commit.
I figured this out.
This keyboard can emit REL_Y/REL_X events between of middle-button events (if user was moving a cursor and press middle button without of stopping this), so this algorithm does a false-positive detection and switches the workaround off like for patched firmware:
Quoted 13 lines
Event: time 1702140625.854777, type 2 (EV_REL), code 1 (REL_Y), value 2
Event: time 1702140625.854777, -------------- SYN_REPORT ------------
Event: time 1702140625.870769, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702140625.870769, -------------- SYN_REPORT ------------
Event: time 1702140625.870771, type 2 (EV_REL), code 1 (REL_Y), value 2
Event: time 1702140625.870771, -------------- SYN_REPORT ------------
Event: time 1702140625.970780, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702140625.970780, -------------- SYN_REPORT ------------
Event: time 1702140626.058800, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702140626.058800, -------------- SYN_REPORT ------------
Event: time 1702140630.462974, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702140630.462974, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702140630.462974, -------------- SYN_REPORT ------------
Maybe we should map the wheel HID reports to REL_Y/REL_X in lenovo_input_mapping_tpIIkbd() to allow libinput to do its wheel emulation job? I tried this but I am not familiar with HID drivers and had no success.
Quoted 62 lines
Quoted 50 lines
There is an evtest output below:
Without of commit:
Middle-button click:
Event: time 1702122290.593300, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702122290.593300, -------------- SYN_REPORT ------------
Event: time 1702122290.593312, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702122290.593312, -------------- SYN_REPORT ------------
Vertical scrolling:
Event: time 1702122300.441627, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702122300.441627, -------------- SYN_REPORT ------------
Event: time 1702122300.565663, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702122300.565663, -------------- SYN_REPORT ------------
Horizontal scrolling:
Event: time 1702122307.845969, type 2 (EV_REL), code 6 (REL_HWHEEL), value -1
Event: time 1702122307.845969, -------------- SYN_REPORT ------------
Event: time 1702122307.981954, type 2 (EV_REL), code 6 (REL_HWHEEL), value -1
Event: time 1702122307.981954, -------------- SYN_REPORT ------------
After commit:
Middle-button click:
Event: time 1702125091.290045, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125091.290045, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702125091.290045, -------------- SYN_REPORT ------------
Event: time 1702125092.626118, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125092.626118, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702125092.626118, -------------- SYN_REPORT ------------
Vscroll:
Event: time 1702125286.653639, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125286.653639, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702125286.653639, -------------- SYN_REPORT ------------
Event: time 1702125287.929689, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702125287.929689, -------------- SYN_REPORT ------------
Event: time 1702125288.037688, type 2 (EV_REL), code 8 (REL_WHEEL), value -1
Event: time 1702125288.037688, -------------- SYN_REPORT ------------
Event: time 1702125290.481787, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125290.481787, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702125290.481787, -------------- SYN_REPORT ------------
Quoted 11 lines
Hscroll:
Event: time 1702125293.841920, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125293.841920, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 1
Event: time 1702125293.841920, -------------- SYN_REPORT ------------
Event: time 1702125294.761952, type 2 (EV_REL), code 6 (REL_HWHEEL), value -1
Event: time 1702125294.761952, -------------- SYN_REPORT ------------
Event: time 1702125294.893967, type 2 (EV_REL), code 6 (REL_HWHEEL), value -1
Event: time 1702125294.893967, -------------- SYN_REPORT ------------
Event: time 1702125296.134006, type 4 (EV_MSC), code 4 (MSC_SCAN), value ffa000fb
Event: time 1702125296.134006, type 1 (EV_KEY), code 274 (BTN_MIDDLE), value 0
Event: time 1702125296.134006, -------------- SYN_REPORT ------------
Quoted 2 lines
--
Yauhen Kharuzhy
--
Yauhen Kharuzhy

Mikhail Khvainitski

author

2023-12-12 13:31 UTC #8 lore raw

PATCH 1/1 HID: lenovo: Restrict detection of patched firmware only to USB cptkbd

Commit 46a0a2c96f0f ("HID: lenovo: Detect quirk-free fw on cptkbd and stop applying workaround") introduced a regression for ThinkPad TrackPoint Keyboard II which has similar quirks to cptkbd (so it uses the same workarounds) but slightly different so that there are false-positives during detecting well-behaving firmware. This commit restricts detecting well-behaving firmware to the only model which known to have one and have stable enough quirks to not cause false-positives.

Fixes 46a0a2c96f0f ("HID: lenovo: Detect quirk-free fw on cptkbd and stop applying workaround")

Link https://lore.kernel.org/linux-input/ZXRiiPsBKNasioqH@jekhomev/ open here

Link https://bbs.archlinux.org/viewtopic.php?pid=2135468#p2135468

Signed-off-by Mikhail Khvainitski <[email protected]>

Tested-by Yauhen Kharuzhy <[email protected]>

---
 drivers/hid/hid-lenovo.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

drivers/hid/hid-lenovo.c +2 -1

index 7c1b33be9d13..149a3c74346b 100644
@@ -692,7 +692,8 @@ static int lenovo_event_cptkbd(struct hid_device *hdev,
 		 * so set middlebutton_state to 3
 		 * to never apply workaround anymore
 		 */
-		if (cptkbd_data->middlebutton_state == 1 &&
+		if (hdev->product == USB_DEVICE_ID_LENOVO_CUSBKBD &&
+				cptkbd_data->middlebutton_state == 1 &&
 				usage->type == EV_REL &&
 				(usage->code == REL_X || usage->code == REL_Y)) {
 			cptkbd_data->middlebutton_state = 3;

Signature · 1 line

2.43.0

Jiri Kosina

Applied

2023-12-12 13:46 UTC #9 lore raw

Re: [PATCH] HID: lenovo: Restrict detection of patched firmware only to USB cptkbd

Quoted 23 lines · Mikhail Khvainitski

Commit 46a0a2c96f0f ("HID: lenovo: Detect quirk-free fw on cptkbd and stop applying workaround") introduced a regression for ThinkPad TrackPoint Keyboard II which has similar quirks to cptkbd (so it uses the same workarounds) but slightly different so that there are false-positives during detecting well-behaving firmware. This commit restricts detecting well-behaving firmware to the only model which known to have one and have stable enough quirks to not cause false-positives.
Fixes 46a0a2c96f0f ("HID: lenovo: Detect quirk-free fw on cptkbd and stop applying workaround")
Link https://lore.kernel.org/linux-input/ZXRiiPsBKNasioqH@jekhomev/ open here
Link https://bbs.archlinux.org/viewtopic.php?pid=2135468#p2135468
Signed-off-by Mikhail Khvainitski <[email protected]>
Tested-by Yauhen Kharuzhy <[email protected]>
---
 drivers/hid/hid-lenovo.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
drivers/hid/hid-lenovo.c +0 -0
index 7c1b33be9d13..149a3c74346b 100644

drivers/hid/hid-lenovo.c static int lenovo_event_cptkbd(struct hid_device *hdev, · line 699

Quoted 9 lines

drivers/hid/hid-lenovo.c +2 -1

@@ -692,7 +692,8 @@ static int lenovo_event_cptkbd(struct hid_device *hdev,
 		 * so set middlebutton_state to 3
 		 * to never apply workaround anymore
 		 */
-		if (cptkbd_data->middlebutton_state == 1 &&
+		if (hdev->product == USB_DEVICE_ID_LENOVO_CUSBKBD &&
+				cptkbd_data->middlebutton_state == 1 &&
 				usage->type == EV_REL &&
 				(usage->code == REL_X || usage->code == REL_Y)) {
 			cptkbd_data->middlebutton_state = 3;

Applied, thanks.

Signature · 2 lines

Jiri Kosina
SUSE Labs

Uli v. d. Ohe

2023-12-22 15:32 UTC #10 lore raw

Re: [PATCH] HID: lenovo: Restrict detection of patched firmware only to USB cptkbd

I get buggy middle button scrolling behavior on my USB Compact Keyboard (i.e., "1st gen") with original, unmodified firmware and the patch (of Sep. 23).

Sometimes the keyboard sends REL_X events while the middle button is pressed. Thus the old "workaround" is disabled and middle button scrolling henceforth exhibits the known buggy behavior.

Explicitly, I can confirm that the following values occur, leading to erroneous disabling of the workaround:

cptkbd_data->middlebutton_state == 1
usage->type == 2 [i.e., EV_REL]
usage->code == 0 [i.e., REL_X]

The keyboard is identified by lsusb as:
ID 17ef:6047 Lenovo ThinkPad Compact Keyboard with TrackPoint

This was tested with kernel 6.1.67 which contains the backported patch (commit 6e2076cad8873cc2a9f96e4becab35425c3656dc).

I didn't test the latest patch of Dec. 12. However, I don't expect it to fix my issue as the only added condition
hdev->product == USB_DEVICE_ID_LENOVO_CUSBKBD
should be satisfied, which I understand is also the intention. (USB_DEVICE_ID_LENOVO_CUSBKBD == 0x6047, which is the device ID of my keyboard as reported by lsusb.)

Best regards,
Uli

Mikhail Khvoinitsky

author

2023-12-23 18:04 UTC #11 lore raw

Re: [PATCH] HID: lenovo: Restrict detection of patched firmware only to USB cptkbd

Hello.

Thank you for the report, sorry about that. I've received one more report of the same issue by email.
So this means that the only reliable way is to add a sysfs parameter. I'll send a patch.

Quoted 31 lines · Uli v. d. Ohe

I get buggy middle button scrolling behavior on my USB Compact Keyboard (i.e., "1st gen") with original, unmodified firmware and the patch (of Sep. 23).
Sometimes the keyboard sends REL_X events while the middle button is pressed. Thus the old "workaround" is disabled and middle button scrolling henceforth exhibits the known buggy behavior.
Explicitly, I can confirm that the following values occur, leading to erroneous disabling of the workaround:
cptkbd_data->middlebutton_state == 1
usage->type == 2 [i.e., EV_REL]
usage->code == 0 [i.e., REL_X]
The keyboard is identified by lsusb as:
ID 17ef:6047 Lenovo ThinkPad Compact Keyboard with TrackPoint
This was tested with kernel 6.1.67 which contains the backported patch (commit 6e2076cad8873cc2a9f96e4becab35425c3656dc).
I didn't test the latest patch of Dec. 12. However, I don't expect it to fix my issue as the only added condition
hdev->product == USB_DEVICE_ID_LENOVO_CUSBKBD
should be satisfied, which I understand is also the intention. (USB_DEVICE_ID_LENOVO_CUSBKBD == 0x6047, which is the device ID of my keyboard as reported by lsusb.)
Best regards,
Uli

Mikhail Khvainitski

author

2023-12-23 19:14 UTC #12 lore raw

PATCH 1/1 HID: lenovo: Add middleclick_workaround sysfs knob for cptkbd

Previous attempt to autodetect well-behaving patched firmware introduced in commit 46a0a2c96f0f ("HID: lenovo: Detect quirk-free fw on cptkbd and stop applying workaround") has shown that there are false-positives on original firmware (on both 1st gen and 2nd gen keyboards) which causes the middle button click workaround to be mistakenly disabled.

This commit adds explicit parameter to sysfs to control this workaround.

Fixes 46a0a2c96f0f ("HID: lenovo: Detect quirk-free fw on cptkbd and stop applying workaround")

Fixes 43527a0094c1 ("HID: lenovo: Restrict detection of patched firmware only to USB cptkbd")

Signed-off-by Mikhail Khvainitski <[email protected]>

---
 drivers/hid/hid-lenovo.c | 57 +++++++++++++++++++++++++++-------------
 1 file changed, 39 insertions(+), 18 deletions(-)

drivers/hid/hid-lenovo.c +39 ~~-18~~

index 149a3c74346b..f86c1ea83a03 100644
@@ -54,10 +54,10 @@ struct lenovo_drvdata {
 	/* 0: Up
 	 * 1: Down (undecided)
 	 * 2: Scrolling
-	 * 3: Patched firmware, disable workaround
 	 */
 	u8 middlebutton_state;
 	bool fn_lock;
+	bool middleclick_workaround_cptkbd;
 };
 
 #define map_key_clear(c) hid_map_usage_clear(hi, usage, bit, max, EV_KEY, (c))

@@ -621,6 +621,36 @@ static ssize_t attr_sensitivity_store_cptkbd(struct device *dev,
 	return count;
 }
 
+static ssize_t attr_middleclick_workaround_show_cptkbd(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct hid_device *hdev = to_hid_device(dev);
+	struct lenovo_drvdata *cptkbd_data = hid_get_drvdata(hdev);
+
+	return snprintf(buf, PAGE_SIZE, "%u\n",
+		cptkbd_data->middleclick_workaround_cptkbd);
+}
+
+static ssize_t attr_middleclick_workaround_store_cptkbd(struct device *dev,
+		struct device_attribute *attr,
+		const char *buf,
+		size_t count)
+{
+	struct hid_device *hdev = to_hid_device(dev);
+	struct lenovo_drvdata *cptkbd_data = hid_get_drvdata(hdev);
+	int value;
+
+	if (kstrtoint(buf, 10, &value))
+		return -EINVAL;
+	if (value < 0 || value > 1)
+		return -EINVAL;
+
+	cptkbd_data->middleclick_workaround_cptkbd = !!value;
+
+	return count;
+}
+
 
 static struct device_attribute dev_attr_fn_lock =
 	__ATTR(fn_lock, S_IWUSR | S_IRUGO,

@@ -632,10 +662,16 @@ static struct device_attribute dev_attr_sensitivity_cptkbd =
 			attr_sensitivity_show_cptkbd,
 			attr_sensitivity_store_cptkbd);
 
+static struct device_attribute dev_attr_middleclick_workaround_cptkbd =
+	__ATTR(middleclick_workaround, S_IWUSR | S_IRUGO,
+			attr_middleclick_workaround_show_cptkbd,
+			attr_middleclick_workaround_store_cptkbd);
+
 
 static struct attribute *lenovo_attributes_cptkbd[] = {
 	&dev_attr_fn_lock.attr,
 	&dev_attr_sensitivity_cptkbd.attr,
+	&dev_attr_middleclick_workaround_cptkbd.attr,
 	NULL
 };

@@ -686,23 +722,7 @@ static int lenovo_event_cptkbd(struct hid_device *hdev,
 {
 	struct lenovo_drvdata *cptkbd_data = hid_get_drvdata(hdev);
 
-	if (cptkbd_data->middlebutton_state != 3) {
-		/* REL_X and REL_Y events during middle button pressed
-		 * are only possible on patched, bug-free firmware
-		 * so set middlebutton_state to 3
-		 * to never apply workaround anymore
-		 */
-		if (hdev->product == USB_DEVICE_ID_LENOVO_CUSBKBD &&
-				cptkbd_data->middlebutton_state == 1 &&
-				usage->type == EV_REL &&
-				(usage->code == REL_X || usage->code == REL_Y)) {
-			cptkbd_data->middlebutton_state = 3;
-			/* send middle button press which was hold before */
-			input_event(field->hidinput->input,
-				EV_KEY, BTN_MIDDLE, 1);
-			input_sync(field->hidinput->input);
-		}
-
+	if (cptkbd_data->middleclick_workaround_cptkbd) {
 		/* "wheel" scroll events */
 		if (usage->type == EV_REL && (usage->code == REL_WHEEL ||
 				usage->code == REL_HWHEEL)) {

@@ -1166,6 +1186,7 @@ static int lenovo_probe_cptkbd(struct hid_device *hdev)
 	cptkbd_data->middlebutton_state = 0;
 	cptkbd_data->fn_lock = true;
 	cptkbd_data->sensitivity = 0x05;
+	cptkbd_data->middleclick_workaround_cptkbd = true;
 	lenovo_features_set_cptkbd(hdev);
 
 	ret = sysfs_create_group(&hdev->dev.kobj, &lenovo_attr_group_cptkbd);

Signature · 1 line

2.43.0

Jiri Kosina

maintainer

2024-01-23 10:55 UTC #13 lore raw

Quoted 7 lines · Mikhail Khvainitski

Previous attempt to autodetect well-behaving patched firmware introduced in commit 46a0a2c96f0f ("HID: lenovo: Detect quirk-free fw on cptkbd and stop applying workaround") has shown that there are false-positives on original firmware (on both 1st gen and 2nd gen keyboards) which causes the middle button click workaround to be mistakenly disabled.

Quoted 6 lines

This commit adds explicit parameter to sysfs to control this workaround.
Fixes 46a0a2c96f0f ("HID: lenovo: Detect quirk-free fw on cptkbd and stop applying workaround")
Fixes 43527a0094c1 ("HID: lenovo: Restrict detection of patched firmware only to USB cptkbd")
Signed-off-by Mikhail Khvainitski <[email protected]>

I am not a huge fan of sysctl device-specific knobs like this, but I guess this is the best we can get here, unfortunately.

Now applied, thanks a lot.

Signature · 2 lines

Jiri Kosina
SUSE Labs

Uli v. d. Ohe

2023-12-24 15:51 UTC #14 lore raw

Re: [PATCH] HID: lenovo: Restrict detection of patched firmware only to USB cptkbd

In reply to Mikhail Khvoinitsky

Quoted 2 lines

So this means that the only reliable way is to add a sysfs parameter. I'll send a patch.

Thank you for the quick action!

Perhaps it would be possible to modify the firmware further in order to facilitate reliable detection of this modified firmware? But for now the solution with a sysfs parameter (and defaulting to the workaround) seems good.

Best regards,
Uli

Yauhen Kharuzhy

2023-12-26 09:36 UTC #15 lore raw

Re: [PATCH] HID: lenovo: Restrict detection of patched firmware only to USB cptkbd

вс, 24 дек. 2023 г. в 18:51, Uli v. d. Ohe <[email protected]>:

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Quoted 3 lines
So this means that the only reliable way is to add a sysfs parameter. I'll send a patch.
Thank you for the quick action!
Perhaps it would be possible to modify the firmware further in order to facilitate reliable detection of this modified firmware? But for now the solution with a sysfs parameter (and defaulting to the workaround) seems good.

Unfortunately no, the firmware is closed-source and was patched in binary form AFAIR (by replacing 1-2 instructions). Moreover, it cannot be updated in the wireless version of the keyboard (ThinkPad Compact Keyboard II).

Quoted 3 lines

Best regards,
Uli

Signature · 1 line

Yauhen Kharuzhy