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(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(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(scpdr, SCPDR);
53		udelay(100);
54		touched = __raw_readb(PHDR) & PHDR_TS_PEN_DOWN;
55	}
56
57	if (touched) {
58		input_report_key(hp680_ts_dev, BTN_TOUCH, 1);
59		input_report_abs(hp680_ts_dev, ABS_X, absx);
60		input_report_abs(hp680_ts_dev, ABS_Y, absy);
61	} else {
62		input_report_key(hp680_ts_dev, BTN_TOUCH, 0);
63	}
64
65	input_sync(hp680_ts_dev);
66	enable_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(&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(hp680_ts_dev, ABS_X,
89		HP680_TS_ABS_X_MIN, HP680_TS_ABS_X_MAX, 0, 0);
90	input_set_abs_params(hp680_ts_dev, ABS_Y,
91		HP680_TS_ABS_Y_MIN, HP680_TS_ABS_Y_MAX, 0, 0);
92
93	hp680_ts_dev->name = "HP Jornada touchscreen";
94	hp680_ts_dev->phys = "hp680_ts/input0";
95
96	if (request_irq(HP680_TS_IRQ, hp680_ts_interrupt,
97			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(&work);
112 fail1:	input_free_device(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(&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