RE: [PATCH] Input: elants_i2c - support palm detection

[Johnny.Chuang]

> -----Original Message-----
> From: Peter Hutterer [mailto:peter.hutterer@xxxxxxxxx]
> Sent: Monday, March 30, 2020 11:48 AM
> To: Johnny.Chuang
> Cc: 'Johnny Chuang'; 'Dmitry Torokhov'; 'Benjamin Tissoires';
> linux-kernel@xxxxxxxxxxxxxxx; linux-input@xxxxxxxxxxxxxxx; 'Rob
Schonberger';
> 'James Chen'; 'Jennifer Tsai'; 'Paul Liang'; 'Jeff Chuang'
> Subject: Re: [PATCH] Input: elants_i2c - support palm detection
> 
> On Mon, Mar 30, 2020 at 08:59:51AM +0800, Johnny.Chuang wrote:
> > > -----Original Message-----
> > > From: Peter Hutterer [mailto:peter.hutterer@xxxxxxxxx]
> > > Sent: Sunday, March 29, 2020 10:15 AM
> > > To: Johnny Chuang
> > > Cc: Dmitry Torokhov; Benjamin Tissoires; linux-kernel@xxxxxxxxxxxxxxx;
> > > linux-input@xxxxxxxxxxxxxxx; Rob Schonberger; Johnny Chuang; James
> Chen;
> > > Jennifer Tsai; Paul Liang; Jeff Chuang
> > > Subject: Re: [PATCH] Input: elants_i2c - support palm detection
> > >
> > > On Thu, Mar 26, 2020 at 03:58:45PM +0800, Johnny Chuang wrote:
> > > > From: Johnny Chuang <johnny.chuang@xxxxxxxxxx>
> > > >
> > > > Elan define finger/palm detection on the least significant bit of
byte
> > 33.
> > > > The default value is 1 for all firmwares, which report as
> > MT_TOOL_FINGER.
> > > > If firmware support palm detection, the bit will change to 0 and
> > > > report as MT_TOOL_PALM when firmware detecting palm.
> > > >
> > > > Signed-off-by: Johnny Chuang <johnny.chuang@xxxxxxxxxx>
> > > > ---
> > > >  drivers/input/touchscreen/elants_i2c.c | 11 ++++++++++-
> > > >  1 file changed, 10 insertions(+), 1 deletion(-)
> > > >
> > > > diff --git a/drivers/input/touchscreen/elants_i2c.c
> > > > b/drivers/input/touchscreen/elants_i2c.c
> > > > index 14c577c..3b4d9eb3 100644
> > > > --- a/drivers/input/touchscreen/elants_i2c.c
> > > > +++ b/drivers/input/touchscreen/elants_i2c.c
> > > > @@ -73,6 +73,7 @@
> > > >  #define FW_POS_STATE		1
> > > >  #define FW_POS_TOTAL		2
> > > >  #define FW_POS_XY		3
> > > > +#define FW_POS_TOOL_TYPE	33
> > > >  #define FW_POS_CHECKSUM		34
> > > >  #define FW_POS_WIDTH		35
> > > >  #define FW_POS_PRESSURE		45
> > > > @@ -842,6 +843,7 @@ static void elants_i2c_mt_event(struct
> elants_data
> > > > *ts, u8 *buf)  {
> > > >  	struct input_dev *input = ts->input;
> > > >  	unsigned int n_fingers;
> > > > +	unsigned int tool_type;
> > > >  	u16 finger_state;
> > > >  	int i;
> > > >
> > > > @@ -852,6 +854,12 @@ static void elants_i2c_mt_event(struct
> elants_data
> > > *ts, u8 *buf)
> > > >  	dev_dbg(&ts->client->dev,
> > > >  		"n_fingers: %u, state: %04x\n",  n_fingers,
finger_state);
> > > >
> > > > +	/* Note: all fingers have the same tool type */
> > > > +	if (buf[FW_POS_TOOL_TYPE] & 0x01)
> > > > +		tool_type = MT_TOOL_FINGER;
> > > > +	else
> > > > +		tool_type = MT_TOOL_PALM;
> > > > +
> > > >  	for (i = 0; i < MAX_CONTACT_NUM && n_fingers; i++) {
> > > >  		if (finger_state & 1) {
> > > >  			unsigned int x, y, p, w;
> > > > @@ -867,7 +875,7 @@ static void elants_i2c_mt_event(struct
> elants_data
> > > *ts, u8 *buf)
> > > >  				i, x, y, p, w);
> > > >
> > > >  			input_mt_slot(input, i);
> > > > -			input_mt_report_slot_state(input,
MT_TOOL_FINGER,
> > true);
> > > > +			input_mt_report_slot_state(input, tool_type,
true);
> > > >  			input_event(input, EV_ABS,
ABS_MT_POSITION_X, x);
> > > >  			input_event(input, EV_ABS,
ABS_MT_POSITION_Y, y);
> > > >  			input_event(input, EV_ABS, ABS_MT_PRESSURE,
p); @@
> > > -1307,6 +1315,7
> > > > @@ static int elants_i2c_probe(struct i2c_client *client,
> > > >  	input_set_abs_params(ts->input, ABS_MT_POSITION_Y, 0,
ts->y_max,
> 0,
> > > 0);
> > > >  	input_set_abs_params(ts->input, ABS_MT_TOUCH_MAJOR, 0, 255,
0,
> 0);
> > > >  	input_set_abs_params(ts->input, ABS_MT_PRESSURE, 0, 255, 0,
0);
> > > > +	input_set_abs_params(ts->input, ABS_MT_TOOL_TYPE, 0,
> > > MT_TOOL_MAX, 0,
> > > > +0);
> > >
> > > if you're only reporting pen and palm, can we set this to MT_TOOL_PALM
> > > instead? Otherwise you're indicating you may also send MT_TOOL_DIAL
> which
> > > is unlikely on this hardware :)
> > >
> >
> > Yes, we do not have MT_TOOL_DIAL on touch screen.
> > So I need to modify MT_TOOL_MAX to MT_TOOL_PALM, right?
> 
> yes please.
> 
> Cheers,
>    Peter
> 

OK, I will submit patch v2 today.

> >
> > > Reviewed-by: Peter Hutterer <peter.hutterer@xxxxxxxxx> otherwise
> > >
> > > Cheers,
> > >    Peter
> > >
> > > >  	input_abs_set_res(ts->input, ABS_MT_POSITION_X, ts->x_res);
> > > >  	input_abs_set_res(ts->input, ABS_MT_POSITION_Y, ts->y_res);
> > > >  	input_abs_set_res(ts->input, ABS_MT_TOUCH_MAJOR, 1);
> > > > --
> > > > 2.7.4
> > > >
> >