Re: [PATCH v8] psmouse - focaltech pass finger width to userspace

[Dmitry Tunin]

I see that I did not change that here.

Width can be in state->width or fingers[finger]->width

I think latter is mere correct.It should be that way in this patch.
I moved ot back and forth and tested. Noticed no difference.

24.04.2015 13:44, Dmitry Tunin ÐÐÑÐÑ:
> 
>>
>> Hi,
>>
>> Some comments below. If it is not a problem that width values are
>> outdated as soon as there are two or more fingers on the touchpad, I
>> think the change is good.
>>
>> Regards,
>> Mathias
>>
>> Am 24.04.2015 um 01:15 schrieb Dmitry Tunin:
>>> Focaltech touchpads report finger width in packet[5] of absolute packet.
>>> Range for width in raw format is 0x10 - 0x70. Second half-byte is always 0.
>>> 0xff is reported, when a large contact area is detected.
>>> This can be handled in userspace.
>>>
>>> Signed-off-by: Dmitry Tunin <hanipouspilot@xxxxxxxxx>
>>> ---
>>>  drivers/input/mouse/focaltech.c | 16 ++++++++++++++--
>>>  1 file changed, 14 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/input/mouse/focaltech.c b/drivers/input/mouse/focaltech.c
>>> index 23d2594..ea53f8b 100644
>>> --- a/drivers/input/mouse/focaltech.c
>>> +++ b/drivers/input/mouse/focaltech.c
>>> @@ -90,6 +90,13 @@ struct focaltech_finger_state {
>>>  	 */
>>>  	unsigned int x;
>>>  	unsigned int y;
>>> +
>>> +	/*
>>> +	* Finger width 0-7 and 15 for 'latching'
>> You already describe below that 15 is latched - what you write above
>> should probably rather be something like "15 if a very large contact
>> area was detected" or something like that.
> 
> OK. No problem.
>>> +	* 15 value stays until the finger is released
>>> +	* Width is reported only in absolute packets
>>> +	*/
>>> +	unsigned int width;
>>>  };
>>>  
>>>  /*
>>> @@ -112,7 +119,7 @@ struct focaltech_data {
>>>  	struct focaltech_hw_state state;
>>>  };
>>>  
>>> -static void focaltech_report_state(struct psmouse *psmouse)
>>> +static void focaltech_report_state(struct psmouse *psmouse, bool abs)
>>>  {
>>>  	struct focaltech_data *priv = psmouse->private;
>>>  	struct focaltech_hw_state *state = &priv->state;
>>> @@ -137,6 +144,7 @@ static void focaltech_report_state(struct psmouse *psmouse)
>>>  			input_report_abs(dev, ABS_MT_POSITION_X, clamped_x);
>>>  			input_report_abs(dev, ABS_MT_POSITION_Y,
>>>  					 priv->y_max - clamped_y);
>>> +			if (abs) input_report_abs(dev, ABS_TOOL_WIDTH, state->width);
>> You are sending width here for *all* fingers, even though only one
>> finger has an up-to-date width value. Is that intentional? I fail to see
>> how that is different from always sending width no matter the packet
>> type, because in any case all but one fingers will have an outdated
>> width value.
> 
> That is not true. Width is reported only in abs packets. So I report width for a specific 
> finger. If multiple fingers are active, this data becomes outdated, when rel packets are processed.
> But we can do nothing with that. The only doubt I have, that we do not need to store all that finger width in
> struct  focaltech_finger_state. It is overkill.
> The only reason for that is to process a situation, when there is one 'thin' touch and another 'palm' touch.
> Userspace driver may ignore the palm, but keep processing a finger. Various userspace drivers can behave in a different way.
> But this is rare. I can move width *all* value to hw_state and forget of each packets. Just report the last one.
> In practice it should not make much difference.
> 
> I already committed this change to ppa with dkms driver, and it can be tested by people.
> 
>>>  		}
>>>  	}
>>>  	input_mt_report_pointer_emulation(dev, true);
>>> @@ -187,6 +195,7 @@ static void focaltech_process_abs_packet(struct psmouse *psmouse,
>>>  
>>>  	state->fingers[finger].x = ((packet[1] & 0xf) << 8) | packet[2];
>>>  	state->fingers[finger].y = (packet[3] << 8) | packet[4];
>>> +	state->fingers[finger].width = packet[5] >> 4;
>>>  	state->fingers[finger].valid = true;
>>>  }
>>>  
>>> @@ -228,14 +237,17 @@ static void focaltech_process_packet(struct psmouse *psmouse)
>>>  	switch (packet[0] & 0xf) {
>>>  	case FOC_TOUCH:
>>>  		focaltech_process_touch_packet(psmouse, packet);
>>> +		focaltech_report_state(psmouse, false);
>>>  		break;
>>>  
>>>  	case FOC_ABS:
>>>  		focaltech_process_abs_packet(psmouse, packet);
>>> +		focaltech_report_state(psmouse, true);
>>>  		break;
>>>  
>>>  	case FOC_REL:
>>>  		focaltech_process_rel_packet(psmouse, packet);
>>> +		focaltech_report_state(psmouse, false);
>>>  		break;
>>>  
>>>  	default:
>>> @@ -243,7 +255,6 @@ static void focaltech_process_packet(struct psmouse *psmouse)
>>>  		break;
>>>  	}
>>>  
>> Remove that blank line as well? :)
>>> -	focaltech_report_state(psmouse);
>>>  }
>>>  
>>>  static psmouse_ret_t focaltech_process_byte(struct psmouse *psmouse)
>>> @@ -331,6 +342,7 @@ static void focaltech_set_input_params(struct psmouse *psmouse)
>>>  	__set_bit(EV_ABS, dev->evbit);
>>>  	input_set_abs_params(dev, ABS_MT_POSITION_X, 0, priv->x_max, 0, 0);
>>>  	input_set_abs_params(dev, ABS_MT_POSITION_Y, 0, priv->y_max, 0, 0);
>>> +	input_set_abs_params(dev, ABS_TOOL_WIDTH, 0, 15, 0, 0);
>>>  	input_mt_init_slots(dev, 5, INPUT_MT_POINTER);
>>>  	__set_bit(INPUT_PROP_BUTTONPAD, dev->propbit);
>>>  }
>>
> 
> Various mistakes in commits are because I have too many trees and versions. 3.16, 3.19 and two dkms, which are a bit different.
> I need to learn sorting that out.
> 
> After someone of maintainers finds time to look at this, I will make a final version.
> 
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