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linux/drivers/input/touchscreen/penmount.c
Erick Archer f81d03d439 Input: touchscreen - use sizeof(*pointer) instead of sizeof(type)
It is preferred to use sizeof(*pointer) instead of sizeof(type)
due to the type of the variable can change and one needs not
change the former (unlike the latter).

The refactoring is mostly trivial except for "usbtouchscreen.c"
file. Here, in the "mtouch_alloc" and "nexio_alloc" functions,
it is necessary to use a variable with a predefined type instead
of the "usbtouch->priv" variable (void * type). This way, the
"sizeof" operator can now know the correct size. Moreover, we
need to set the "usbtouch->priv" pointer after the memory
allocation since now the "kmalloc" return value is not assigned
directly.

This patch has no effect on runtime behavior.

Signed-off-by: Erick Archer <erick.archer@outlook.com>
Link: https://lore.kernel.org/r/AS8PR02MB723708364CC0DF2EAAFEE5968BC42@AS8PR02MB7237.eurprd02.prod.outlook.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2024-06-09 14:38:38 -07:00

316 lines
6.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Penmount serial touchscreen driver
*
* Copyright (c) 2006 Rick Koch <n1gp@hotmail.com>
* Copyright (c) 2011 John Sung <penmount.touch@gmail.com>
*
* Based on ELO driver (drivers/input/touchscreen/elo.c)
* Copyright (c) 2004 Vojtech Pavlik
*/
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/serio.h>
#define DRIVER_DESC "PenMount serial touchscreen driver"
MODULE_AUTHOR("Rick Koch <n1gp@hotmail.com>");
MODULE_AUTHOR("John Sung <penmount.touch@gmail.com>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
/*
* Definitions & global arrays.
*/
#define PM_MAX_LENGTH 6
#define PM_MAX_MTSLOT 16
#define PM_3000_MTSLOT 2
#define PM_6250_MTSLOT 12
/*
* Multi-touch slot
*/
struct mt_slot {
unsigned short x, y;
bool active; /* is the touch valid? */
};
/*
* Per-touchscreen data.
*/
struct pm {
struct input_dev *dev;
struct serio *serio;
int idx;
unsigned char data[PM_MAX_LENGTH];
char phys[32];
unsigned char packetsize;
unsigned char maxcontacts;
struct mt_slot slots[PM_MAX_MTSLOT];
void (*parse_packet)(struct pm *);
};
/*
* pm_mtevent() sends mt events and also emulates pointer movement
*/
static void pm_mtevent(struct pm *pm, struct input_dev *input)
{
int i;
for (i = 0; i < pm->maxcontacts; ++i) {
input_mt_slot(input, i);
input_mt_report_slot_state(input, MT_TOOL_FINGER,
pm->slots[i].active);
if (pm->slots[i].active) {
input_event(input, EV_ABS, ABS_MT_POSITION_X, pm->slots[i].x);
input_event(input, EV_ABS, ABS_MT_POSITION_Y, pm->slots[i].y);
}
}
input_mt_report_pointer_emulation(input, true);
input_sync(input);
}
/*
* pm_checkpacket() checks if data packet is valid
*/
static bool pm_checkpacket(unsigned char *packet)
{
int total = 0;
int i;
for (i = 0; i < 5; i++)
total += packet[i];
return packet[5] == (unsigned char)~(total & 0xff);
}
static void pm_parse_9000(struct pm *pm)
{
struct input_dev *dev = pm->dev;
if ((pm->data[0] & 0x80) && pm->packetsize == ++pm->idx) {
input_report_abs(dev, ABS_X, pm->data[1] * 128 + pm->data[2]);
input_report_abs(dev, ABS_Y, pm->data[3] * 128 + pm->data[4]);
input_report_key(dev, BTN_TOUCH, !!(pm->data[0] & 0x40));
input_sync(dev);
pm->idx = 0;
}
}
static void pm_parse_6000(struct pm *pm)
{
struct input_dev *dev = pm->dev;
if ((pm->data[0] & 0xbf) == 0x30 && pm->packetsize == ++pm->idx) {
if (pm_checkpacket(pm->data)) {
input_report_abs(dev, ABS_X,
pm->data[2] * 256 + pm->data[1]);
input_report_abs(dev, ABS_Y,
pm->data[4] * 256 + pm->data[3]);
input_report_key(dev, BTN_TOUCH, pm->data[0] & 0x40);
input_sync(dev);
}
pm->idx = 0;
}
}
static void pm_parse_3000(struct pm *pm)
{
struct input_dev *dev = pm->dev;
if ((pm->data[0] & 0xce) == 0x40 && pm->packetsize == ++pm->idx) {
if (pm_checkpacket(pm->data)) {
int slotnum = pm->data[0] & 0x0f;
pm->slots[slotnum].active = pm->data[0] & 0x30;
pm->slots[slotnum].x = pm->data[2] * 256 + pm->data[1];
pm->slots[slotnum].y = pm->data[4] * 256 + pm->data[3];
pm_mtevent(pm, dev);
}
pm->idx = 0;
}
}
static void pm_parse_6250(struct pm *pm)
{
struct input_dev *dev = pm->dev;
if ((pm->data[0] & 0xb0) == 0x30 && pm->packetsize == ++pm->idx) {
if (pm_checkpacket(pm->data)) {
int slotnum = pm->data[0] & 0x0f;
pm->slots[slotnum].active = pm->data[0] & 0x40;
pm->slots[slotnum].x = pm->data[2] * 256 + pm->data[1];
pm->slots[slotnum].y = pm->data[4] * 256 + pm->data[3];
pm_mtevent(pm, dev);
}
pm->idx = 0;
}
}
static irqreturn_t pm_interrupt(struct serio *serio,
unsigned char data, unsigned int flags)
{
struct pm *pm = serio_get_drvdata(serio);
pm->data[pm->idx] = data;
pm->parse_packet(pm);
return IRQ_HANDLED;
}
/*
* pm_disconnect() is the opposite of pm_connect()
*/
static void pm_disconnect(struct serio *serio)
{
struct pm *pm = serio_get_drvdata(serio);
serio_close(serio);
input_unregister_device(pm->dev);
kfree(pm);
serio_set_drvdata(serio, NULL);
}
/*
* pm_connect() is the routine that is called when someone adds a
* new serio device that supports PenMount protocol and registers it as
* an input device.
*/
static int pm_connect(struct serio *serio, struct serio_driver *drv)
{
struct pm *pm;
struct input_dev *input_dev;
int max_x, max_y;
int err;
pm = kzalloc(sizeof(*pm), GFP_KERNEL);
input_dev = input_allocate_device();
if (!pm || !input_dev) {
err = -ENOMEM;
goto fail1;
}
pm->serio = serio;
pm->dev = input_dev;
snprintf(pm->phys, sizeof(pm->phys), "%s/input0", serio->phys);
pm->maxcontacts = 1;
input_dev->name = "PenMount Serial TouchScreen";
input_dev->phys = pm->phys;
input_dev->id.bustype = BUS_RS232;
input_dev->id.vendor = SERIO_PENMOUNT;
input_dev->id.product = 0;
input_dev->id.version = 0x0100;
input_dev->dev.parent = &serio->dev;
input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
switch (serio->id.id) {
default:
case 0:
pm->packetsize = 5;
pm->parse_packet = pm_parse_9000;
input_dev->id.product = 0x9000;
max_x = max_y = 0x3ff;
break;
case 1:
pm->packetsize = 6;
pm->parse_packet = pm_parse_6000;
input_dev->id.product = 0x6000;
max_x = max_y = 0x3ff;
break;
case 2:
pm->packetsize = 6;
pm->parse_packet = pm_parse_3000;
input_dev->id.product = 0x3000;
max_x = max_y = 0x7ff;
pm->maxcontacts = PM_3000_MTSLOT;
break;
case 3:
pm->packetsize = 6;
pm->parse_packet = pm_parse_6250;
input_dev->id.product = 0x6250;
max_x = max_y = 0x3ff;
pm->maxcontacts = PM_6250_MTSLOT;
break;
}
input_set_abs_params(pm->dev, ABS_X, 0, max_x, 0, 0);
input_set_abs_params(pm->dev, ABS_Y, 0, max_y, 0, 0);
if (pm->maxcontacts > 1) {
input_mt_init_slots(pm->dev, pm->maxcontacts, 0);
input_set_abs_params(pm->dev,
ABS_MT_POSITION_X, 0, max_x, 0, 0);
input_set_abs_params(pm->dev,
ABS_MT_POSITION_Y, 0, max_y, 0, 0);
}
serio_set_drvdata(serio, pm);
err = serio_open(serio, drv);
if (err)
goto fail2;
err = input_register_device(pm->dev);
if (err)
goto fail3;
return 0;
fail3: serio_close(serio);
fail2: serio_set_drvdata(serio, NULL);
fail1: input_free_device(input_dev);
kfree(pm);
return err;
}
/*
* The serio driver structure.
*/
static const struct serio_device_id pm_serio_ids[] = {
{
.type = SERIO_RS232,
.proto = SERIO_PENMOUNT,
.id = SERIO_ANY,
.extra = SERIO_ANY,
},
{ 0 }
};
MODULE_DEVICE_TABLE(serio, pm_serio_ids);
static struct serio_driver pm_drv = {
.driver = {
.name = "serio-penmount",
},
.description = DRIVER_DESC,
.id_table = pm_serio_ids,
.interrupt = pm_interrupt,
.connect = pm_connect,
.disconnect = pm_disconnect,
};
module_serio_driver(pm_drv);