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