linux-kernel - Re: [PATCH v4 8/9] Input: atmel_mxt_ts

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <d5a7f130-ef12-2e1d-c842-eef62899a31a@itdev.co.uk>
Date:	Mon, 20 Jun 2016 17:18:30 +0100
From:	Nick Dyer <nick.dyer@...ev.co.uk>
To:	Hans Verkuil <hverkuil@...all.nl>
Cc:	Dmitry Torokhov <dmitry.torokhov@...il.com>,
	linux-input@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-media@...r.kernel.org,
	Benjamin Tissoires <benjamin.tissoires@...hat.com>,
	Benson Leung <bleung@...omium.org>,
	Alan Bowens <Alan.Bowens@...el.com>,
	Javier Martinez Canillas <javier@....samsung.com>,
	Chris Healy <cphealy@...il.com>,
	Henrik Rydberg <rydberg@...math.org>,
	Andrew Duggan <aduggan@...aptics.com>,
	James Chen <james.chen@....com.tw>,
	Dudley Du <dudl@...ress.com>,
	Andrew de los Reyes <adlr@...omium.org>,
	sheckylin@...omium.org, Peter Hutterer <peter.hutterer@...-t.net>,
	Florian Echtler <floe@...terbrot.org>, mchehab@....samsung.com
Subject: Re: [PATCH v4 8/9] Input: atmel_mxt_ts - add support for reference
 data

On 20/06/2016 17:09, Hans Verkuil wrote:
> On 06/17/2016 04:16 PM, Nick Dyer wrote:
>> @@ -2325,11 +2344,20 @@ static int mxt_vidioc_querycap(struct file *file, void *priv,
>>  static int mxt_vidioc_enum_input(struct file *file, void *priv,
>>  				   struct v4l2_input *i)
>>  {
>> -	if (i->index > 0)
>> +	if (i->index >= MXT_V4L_INPUT_MAX)
>>  		return -EINVAL;
>>  
>>  	i->type = V4L2_INPUT_TYPE_TOUCH_SENSOR;
>> -	strlcpy(i->name, "Mutual References", sizeof(i->name));
>> +
>> +	switch (i->index) {
>> +	case MXT_V4L_INPUT_REFS:
>> +		strlcpy(i->name, "Mutual References", sizeof(i->name));
>> +		break;
>> +	case MXT_V4L_INPUT_DELTAS:
>> +		strlcpy(i->name, "Mutual Deltas", sizeof(i->name));
> 
> I don't think this name is very clear. I have no idea how to interpret "Mutual"
> in this context.

"Mutual" is a touch domain specific term, it means the delta value is for
the capacitance between the horizontal and vertical lines at a particular
"node" on the touchscreen matrix, see
https://en.wikipedia.org/wiki/Touchscreen#Mutual_capacitance

I'll put in a comment.

> 
>> +		break;
>> +	}
>> +
>>  	return 0;
>>  }
>>  
>> @@ -2337,12 +2365,16 @@ static int mxt_set_input(struct mxt_data *data, unsigned int i)
>>  {
>>  	struct v4l2_pix_format *f = &data->dbg.format;
>>  
>> -	if (i > 0)
>> +	if (i >= MXT_V4L_INPUT_MAX)
>>  		return -EINVAL;
>>  
>> +	if (i == MXT_V4L_INPUT_DELTAS)
>> +		f->pixelformat = V4L2_PIX_FMT_YS16;
>> +	else
>> +		f->pixelformat = V4L2_PIX_FMT_Y16;
> 
> You probably need a V4L2_TOUCH_FMT_U16 or something for this as well. It certainly
> needs to be documented.

OK, will change this.