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From:   Mattijs Korpershoek <mkorpershoek@baylibre.com>
To:     Eirin Nya <nyanpasu256@gmail.com>, linux-input@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/3] Input: Remove redundant field elantech_data::y_max
In-Reply-To: <20220929082119.22112-2-nyanpasu256@gmail.com>
References: <20220929082119.22112-1-nyanpasu256@gmail.com>
 <20220929082119.22112-2-nyanpasu256@gmail.com>
Date:   Fri, 07 Oct 2022 15:28:19 +0200
Message-ID: <87ilkv7ogc.fsf@mkorpershoek-xps-13-9370.home>
MIME-Version: 1.0
Content-Type: text/plain
Precedence: bulk

Hi Eirin,

Thank you for your patch.

On Thu, Sep 29, 2022 at 01:21, Eirin Nya <nyanpasu256@gmail.com> wrote:

> elantech_data::y_max is copied from elantech_device_info::y_max, and
> neither is mutated after initialization. So remove the redundant
> variable to prevent future bugs when updating y_max.
>
> Signed-off-by: Eirin Nya <nyanpasu256@gmail.com>
> ---
>  drivers/input/mouse/elantech.c | 17 ++++++++---------
>  drivers/input/mouse/elantech.h |  1 -
>  2 files changed, 8 insertions(+), 10 deletions(-)

Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>

>
> diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
> index ece97f8c6a..79e31611fc 100644
> --- a/drivers/input/mouse/elantech.c
> +++ b/drivers/input/mouse/elantech.c
> @@ -360,7 +360,7 @@ static void elantech_report_absolute_v1(struct psmouse *psmouse)
>  		input_report_abs(dev, ABS_X,
>  			((packet[1] & 0x0c) << 6) | packet[2]);
>  		input_report_abs(dev, ABS_Y,
> -			etd->y_max - (((packet[1] & 0x03) << 8) | packet[3]));
> +			etd->info.y_max - (((packet[1] & 0x03) << 8) | packet[3]));
>  	}
>  
>  	input_report_key(dev, BTN_TOOL_FINGER, fingers == 1);
> @@ -435,7 +435,7 @@ static void elantech_report_absolute_v2(struct psmouse *psmouse)
>  		 * byte 4:  .   .   .   .  y11 y10 y9  y8
>  		 * byte 5: y7  y6  y5  y4  y3  y2  y1  y0
>  		 */
> -		y1 = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
> +		y1 = etd->info.y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
>  
>  		pres = (packet[1] & 0xf0) | ((packet[4] & 0xf0) >> 4);
>  		width = ((packet[0] & 0x30) >> 2) | ((packet[3] & 0x30) >> 4);
> @@ -450,7 +450,7 @@ static void elantech_report_absolute_v2(struct psmouse *psmouse)
>  		 */
>  		x1 = (((packet[0] & 0x10) << 4) | packet[1]) << 2;
>  		/* byte 2: ay7 ay6 ay5 ay4 ay3 ay2 ay1 ay0 */
> -		y1 = etd->y_max -
> +		y1 = etd->info.y_max -
>  			((((packet[0] & 0x20) << 3) | packet[2]) << 2);
>  		/*
>  		 * byte 3:  .   .  by8 bx8  .   .   .   .
> @@ -458,7 +458,7 @@ static void elantech_report_absolute_v2(struct psmouse *psmouse)
>  		 */
>  		x2 = (((packet[3] & 0x10) << 4) | packet[4]) << 2;
>  		/* byte 5: by7 by8 by5 by4 by3 by2 by1 by0 */
> -		y2 = etd->y_max -
> +		y2 = etd->info.y_max -
>  			((((packet[3] & 0x20) << 3) | packet[5]) << 2);
>  
>  		/* Unknown so just report sensible values */
> @@ -579,7 +579,7 @@ static void elantech_report_absolute_v3(struct psmouse *psmouse,
>  		 * byte 4:  .   .   .   .  y11 y10 y9  y8
>  		 * byte 5: y7  y6  y5  y4  y3  y2  y1  y0
>  		 */
> -		y1 = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
> +		y1 = etd->info.y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
>  		break;
>  
>  	case 2:
> @@ -593,7 +593,7 @@ static void elantech_report_absolute_v3(struct psmouse *psmouse,
>  			 * byte 4:   .    .    .    .  ay11 ay10 ay9  ay8
>  			 * byte 5: ay7  ay6  ay5  ay4  ay3  ay2  ay1  ay0
>  			 */
> -			etd->mt[0].y = etd->y_max -
> +			etd->mt[0].y = etd->info.y_max -
>  				(((packet[4] & 0x0f) << 8) | packet[5]);
>  			/*
>  			 * wait for next packet
> @@ -605,7 +605,7 @@ static void elantech_report_absolute_v3(struct psmouse *psmouse,
>  		x1 = etd->mt[0].x;
>  		y1 = etd->mt[0].y;
>  		x2 = ((packet[1] & 0x0f) << 8) | packet[2];
> -		y2 = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
> +		y2 = etd->info.y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
>  		break;
>  	}
>  
> @@ -681,7 +681,7 @@ static void process_packet_head_v4(struct psmouse *psmouse)
>  		return;
>  
>  	etd->mt[id].x = ((packet[1] & 0x0f) << 8) | packet[2];
> -	etd->mt[id].y = etd->y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
> +	etd->mt[id].y = etd->info.y_max - (((packet[4] & 0x0f) << 8) | packet[5]);
>  	pres = (packet[1] & 0xf0) | ((packet[4] & 0xf0) >> 4);
>  	traces = (packet[0] & 0xf0) >> 4;
>  
> @@ -1253,7 +1253,6 @@ static int elantech_set_input_params(struct psmouse *psmouse)
>  		input_abs_set_res(dev, ABS_MT_POSITION_Y, info->y_res);
>  	}
>  
> -	etd->y_max = y_max;
>  	etd->width = width;
>  
>  	return 0;
> diff --git a/drivers/input/mouse/elantech.h b/drivers/input/mouse/elantech.h
> index 571e6ca11d..1ec004f72d 100644
> --- a/drivers/input/mouse/elantech.h
> +++ b/drivers/input/mouse/elantech.h
> @@ -180,7 +180,6 @@ struct elantech_data {
>  	unsigned char reg_25;
>  	unsigned char reg_26;
>  	unsigned int single_finger_reports;
> -	unsigned int y_max;
>  	unsigned int width;
>  	struct finger_pos mt[ETP_MAX_FINGERS];
>  	unsigned char parity[256];
> -- 
> 2.37.3