1// SPDX-License-Identifier: GPL-2.0-only
2#include <linux/input.h>
3#include <linux/module.h>
4#include <linux/init.h>
5#include <linux/interrupt.h>
6#include <asm/io.h>
7#include <asm/delay.h>
8#include <asm/adc.h>
9#include <mach/hp6xx.h>
10
11#define MODNAME "hp680_ts_input"
12
13#define HP680_TS_ABS_X_MIN 40
14#define HP680_TS_ABS_X_MAX 950
15#define HP680_TS_ABS_Y_MIN 80
16#define HP680_TS_ABS_Y_MAX 910
17
18#define PHDR 0xa400012e
19#define SCPDR 0xa4000136
20
21static void do_softint(struct work_struct *work);
22
23static struct input_dev *hp680_ts_dev;
24static DECLARE_DELAYED_WORK(work, do_softint);
25
26static void do_softint(struct work_struct *work)
27{
28 int absx = 0, absy = 0;
29 u8 scpdr;
30 int touched = 0;
31
32 if (__raw_readb(PHDR) & PHDR_TS_PEN_DOWN) {
33 scpdr = __raw_readb(SCPDR);
34 scpdr |= SCPDR_TS_SCAN_ENABLE;
35 scpdr &= ~SCPDR_TS_SCAN_Y;
36 __raw_writeb(val: scpdr, SCPDR);
37 udelay(30);
38
39 absy = adc_single(ADC_CHANNEL_TS_Y);
40
41 scpdr = __raw_readb(SCPDR);
42 scpdr |= SCPDR_TS_SCAN_Y;
43 scpdr &= ~SCPDR_TS_SCAN_X;
44 __raw_writeb(val: scpdr, SCPDR);
45 udelay(30);
46
47 absx = adc_single(ADC_CHANNEL_TS_X);
48
49 scpdr = __raw_readb(SCPDR);
50 scpdr |= SCPDR_TS_SCAN_X;
51 scpdr &= ~SCPDR_TS_SCAN_ENABLE;
52 __raw_writeb(val: scpdr, SCPDR);
53 udelay(100);
54 touched = __raw_readb(PHDR) & PHDR_TS_PEN_DOWN;
55 }
56
57 if (touched) {
58 input_report_key(dev: hp680_ts_dev, BTN_TOUCH, value: 1);
59 input_report_abs(dev: hp680_ts_dev, ABS_X, value: absx);
60 input_report_abs(dev: hp680_ts_dev, ABS_Y, value: absy);
61 } else {
62 input_report_key(dev: hp680_ts_dev, BTN_TOUCH, value: 0);
63 }
64
65 input_sync(dev: hp680_ts_dev);
66 enable_irq(irq: HP680_TS_IRQ);
67}
68
69static irqreturn_t hp680_ts_interrupt(int irq, void *dev)
70{
71 disable_irq_nosync(irq);
72 schedule_delayed_work(dwork: &work, HZ / 20);
73
74 return IRQ_HANDLED;
75}
76
77static int __init hp680_ts_init(void)
78{
79 int err;
80
81 hp680_ts_dev = input_allocate_device();
82 if (!hp680_ts_dev)
83 return -ENOMEM;
84
85 hp680_ts_dev->evbit[0] = BIT_MASK(EV_ABS) | BIT_MASK(EV_KEY);
86 hp680_ts_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
87
88 input_set_abs_params(dev: hp680_ts_dev, ABS_X,
89 HP680_TS_ABS_X_MIN, HP680_TS_ABS_X_MAX, fuzz: 0, flat: 0);
90 input_set_abs_params(dev: hp680_ts_dev, ABS_Y,
91 HP680_TS_ABS_Y_MIN, HP680_TS_ABS_Y_MAX, fuzz: 0, flat: 0);
92
93 hp680_ts_dev->name = "HP Jornada touchscreen";
94 hp680_ts_dev->phys = "hp680_ts/input0";
95
96 if (request_irq(irq: HP680_TS_IRQ, handler: hp680_ts_interrupt,
97 flags: 0, MODNAME, NULL) < 0) {
98 printk(KERN_ERR "hp680_touchscreen.c: Can't allocate irq %d\n",
99 HP680_TS_IRQ);
100 err = -EBUSY;
101 goto fail1;
102 }
103
104 err = input_register_device(hp680_ts_dev);
105 if (err)
106 goto fail2;
107
108 return 0;
109
110 fail2: free_irq(HP680_TS_IRQ, NULL);
111 cancel_delayed_work_sync(dwork: &work);
112 fail1: input_free_device(dev: hp680_ts_dev);
113 return err;
114}
115
116static void __exit hp680_ts_exit(void)
117{
118 free_irq(HP680_TS_IRQ, NULL);
119 cancel_delayed_work_sync(dwork: &work);
120 input_unregister_device(hp680_ts_dev);
121}
122
123module_init(hp680_ts_init);
124module_exit(hp680_ts_exit);
125
126MODULE_AUTHOR("Andriy Skulysh, askulysh@image.kiev.ua");
127MODULE_DESCRIPTION("HP Jornada 680 touchscreen driver");
128MODULE_LICENSE("GPL");
129

source code of linux/drivers/input/touchscreen/hp680_ts_input.c