linux-kernel - Re: [PATCH] Input: synaptics - fix device info appearing different on reconnect

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Message-ID: <20170828173027.GH12195@dtor-ws>
Date:   Mon, 28 Aug 2017 10:30:27 -0700
From:   Dmitry Torokhov <dmitry.torokhov@...il.com>
To:     Anthony Martin <ality@...ane.org>
Cc:     linux-input@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] Input: synaptics - fix device info appearing different
 on reconnect

On Tue, Aug 01, 2017 at 06:40:04AM -0700, Anthony Martin wrote:
> User-modified input settings no longer survive a suspend/resume cycle.
> Starting with 4.12, the touchpad is reinitialized on every reconnect
> because the hardware appears to be different. This can be reproduced
> by running the following as root:
> 
>     echo -n reconnect >/sys/devices/platform/i8042/serio1/drvctl
> 
> A line like the following will show up in dmesg:
> 
>     [30378.295794] psmouse serio1: synaptics: hardware appears to be
>                    different: id(149271-149271), model(114865-114865),
>                    caps(d047b3-d047b1), ext(b40000-b40000).
> 
> Note the single bit difference in caps: bit 1 (SYN_CAP_MULTIFINGER).
> 
> This happens because we modify our stored copy of the device info
> capabilities when we enable advanced gesture mode but this change is
> not reflected in the actual hardware capabilities.
> 
> It worked in the past because synaptics_query_hardware used to modify
> the stored synaptics_device_info struct instead of filling in a new
> one, as it does now.
> 
> Fix it by no longer faking the SYN_CAP_MULTIFINGER bit when setting
> advanced gesture mode. This necessitated a small refactoring.
> 
> Fixes: 6c53694fb222 ("Input: synaptics - split device info into a separate structure")
> Signed-off-by: Anthony Martin <ality@...ane.org>

Applied, thank you.

> ---
>  drivers/input/mouse/synaptics.c | 35 ++++++++++++++++++++---------------
>  1 file changed, 20 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/input/mouse/synaptics.c b/drivers/input/mouse/synaptics.c
> index 16c30460ef04..5af0b7d200bc 100644
> --- a/drivers/input/mouse/synaptics.c
> +++ b/drivers/input/mouse/synaptics.c
> @@ -535,16 +535,17 @@ static void synaptics_apply_quirks(struct psmouse *psmouse,
>  	}
>  }
>  
> +static bool synaptics_has_agm(struct synaptics_data *priv)
> +{
> +	return (SYN_CAP_ADV_GESTURE(priv->info.ext_cap_0c) ||
> +		SYN_CAP_IMAGE_SENSOR(priv->info.ext_cap_0c));
> +}
> +
>  static int synaptics_set_advanced_gesture_mode(struct psmouse *psmouse)
>  {
>  	static u8 param = 0xc8;
> -	struct synaptics_data *priv = psmouse->private;
>  	int error;
>  
> -	if (!(SYN_CAP_ADV_GESTURE(priv->info.ext_cap_0c) ||
> -	      SYN_CAP_IMAGE_SENSOR(priv->info.ext_cap_0c)))
> -		return 0;
> -
>  	error = psmouse_sliced_command(psmouse, SYN_QUE_MODEL);
>  	if (error)
>  		return error;
> @@ -553,9 +554,6 @@ static int synaptics_set_advanced_gesture_mode(struct psmouse *psmouse)
>  	if (error)
>  		return error;
>  
> -	/* Advanced gesture mode also sends multi finger data */
> -	priv->info.capabilities |= BIT(1);
> -
>  	return 0;
>  }
>  
> @@ -578,7 +576,7 @@ static int synaptics_set_mode(struct psmouse *psmouse)
>  	if (error)
>  		return error;
>  
> -	if (priv->absolute_mode) {
> +	if (priv->absolute_mode && synaptics_has_agm(priv)) {
>  		error = synaptics_set_advanced_gesture_mode(psmouse);
>  		if (error) {
>  			psmouse_err(psmouse,
> @@ -766,9 +764,7 @@ static int synaptics_parse_hw_state(const u8 buf[],
>  			 ((buf[0] & 0x04) >> 1) |
>  			 ((buf[3] & 0x04) >> 2));
>  
> -		if ((SYN_CAP_ADV_GESTURE(priv->info.ext_cap_0c) ||
> -			SYN_CAP_IMAGE_SENSOR(priv->info.ext_cap_0c)) &&
> -		    hw->w == 2) {
> +		if (synaptics_has_agm(priv) && hw->w == 2) {
>  			synaptics_parse_agm(buf, priv, hw);
>  			return 1;
>  		}
> @@ -1033,6 +1029,15 @@ static void synaptics_image_sensor_process(struct psmouse *psmouse,
>  	synaptics_report_mt_data(psmouse, sgm, num_fingers);
>  }
>  
> +static bool synaptics_has_multifinger(struct synaptics_data *priv)
> +{
> +	if (SYN_CAP_MULTIFINGER(priv->info.capabilities))
> +		return true;
> +
> +	/* Advanced gesture mode also sends multi finger data */
> +	return synaptics_has_agm(priv);
> +}
> +
>  /*
>   *  called for each full received packet from the touchpad
>   */
> @@ -1079,7 +1084,7 @@ static void synaptics_process_packet(struct psmouse *psmouse)
>  		if (SYN_CAP_EXTENDED(info->capabilities)) {
>  			switch (hw.w) {
>  			case 0 ... 1:
> -				if (SYN_CAP_MULTIFINGER(info->capabilities))
> +				if (synaptics_has_multifinger(priv))
>  					num_fingers = hw.w + 2;
>  				break;
>  			case 2:
> @@ -1123,7 +1128,7 @@ static void synaptics_process_packet(struct psmouse *psmouse)
>  		input_report_abs(dev, ABS_TOOL_WIDTH, finger_width);
>  
>  	input_report_key(dev, BTN_TOOL_FINGER, num_fingers == 1);
> -	if (SYN_CAP_MULTIFINGER(info->capabilities)) {
> +	if (synaptics_has_multifinger(priv)) {
>  		input_report_key(dev, BTN_TOOL_DOUBLETAP, num_fingers == 2);
>  		input_report_key(dev, BTN_TOOL_TRIPLETAP, num_fingers == 3);
>  	}
> @@ -1283,7 +1288,7 @@ static void set_input_params(struct psmouse *psmouse,
>  	__set_bit(BTN_TOUCH, dev->keybit);
>  	__set_bit(BTN_TOOL_FINGER, dev->keybit);
>  
> -	if (SYN_CAP_MULTIFINGER(info->capabilities)) {
> +	if (synaptics_has_multifinger(priv)) {
>  		__set_bit(BTN_TOOL_DOUBLETAP, dev->keybit);
>  		__set_bit(BTN_TOOL_TRIPLETAP, dev->keybit);
>  	}
> -- 
> 2.13.3
> 

-- 
Dmitry