drivers/input/touchscreen/hp680_ts_input.c

   1 #include <linux/input.h>
   2 #include <linux/module.h>
   3 #include <linux/init.h>
   4
   5 #include <linux/interrupt.h>
   6 #include <asm/io.h>
   7 #include <asm/delay.h>
   8 #include <asm/adc.h>
   9 #include <asm/hp6xx/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
  21 static void do_softint(void *data);
  22
  23 static struct input_dev *hp680_ts_dev;
  24 static DECLARE_WORK(work, do_softint, 0);
  25
  26 static void do_softint(void *data)
  27 {
  28         int absx = 0, absy = 0;
  29         u8 scpdr;
  30         int touched = 0;
  31
  32         if (ctrl_inb(PHDR) & PHDR_TS_PEN_DOWN) {
  33                 scpdr = ctrl_inb(SCPDR);
  34                 scpdr |= SCPDR_TS_SCAN_ENABLE;
  35                 scpdr &= ~SCPDR_TS_SCAN_Y;
  36                 ctrl_outb(scpdr, SCPDR);
  37                 udelay(30);
  38
  39                 absy = adc_single(ADC_CHANNEL_TS_Y);
  40
  41                 scpdr = ctrl_inb(SCPDR);
  42                 scpdr |= SCPDR_TS_SCAN_Y;
  43                 scpdr &= ~SCPDR_TS_SCAN_X;
  44                 ctrl_outb(scpdr, SCPDR);
  45                 udelay(30);
  46
  47                 absx = adc_single(ADC_CHANNEL_TS_X);
  48
  49                 scpdr = ctrl_inb(SCPDR);
  50                 scpdr |= SCPDR_TS_SCAN_X;
  51                 scpdr &= ~SCPDR_TS_SCAN_ENABLE;
  52                 ctrl_outb(scpdr, SCPDR);
  53                 udelay(100);
  54                 touched = ctrl_inb(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
  69 static irqreturn_t hp680_ts_interrupt(int irq, void *dev, struct pt_regs *regs)
  70 {
  71         disable_irq_nosync(irq);
  72         schedule_delayed_work(&work, HZ / 20);
  73
  74         return IRQ_HANDLED;
  75 }
  76
  77 static int __init hp680_ts_init(void)
  78 {
  79         hp680_ts_dev = input_allocate_device();
  80         if (!hp680_ts_dev)
  81                 return -ENOMEM;
  82
  83         hp680_ts_dev->evbit[0] = BIT(EV_ABS) | BIT(EV_KEY);
  84         hp680_ts_dev->absbit[0] = BIT(ABS_X) | BIT(ABS_Y);
  85         hp680_ts_dev->keybit[LONG(BTN_TOUCH)] = BIT(BTN_TOUCH);
  86
  87         hp680_ts_dev->absmin[ABS_X] = HP680_TS_ABS_X_MIN;
  88         hp680_ts_dev->absmin[ABS_Y] = HP680_TS_ABS_Y_MIN;
  89         hp680_ts_dev->absmax[ABS_X] = HP680_TS_ABS_X_MAX;
  90         hp680_ts_dev->absmax[ABS_Y] = HP680_TS_ABS_Y_MAX;
  91
  92         hp680_ts_dev->name = "HP Jornada touchscreen";
  93         hp680_ts_dev->phys = "hp680_ts/input0";
  94
  95         input_register_device(hp680_ts_dev);
  96
  97         if (request_irq(HP680_TS_IRQ, hp680_ts_interrupt,
  98                         IRQF_DISABLED, MODNAME, 0) < 0) {
  99                 printk(KERN_ERR "hp680_touchscreen.c: Can't allocate irq %d\n",
 100                        HP680_TS_IRQ);
 101                 input_unregister_device(hp680_ts_dev);
 102                 return -EBUSY;
 103         }
 104
 105         return 0;
 106 }
 107
 108 static void __exit hp680_ts_exit(void)
 109 {
 110         free_irq(HP680_TS_IRQ, 0);
 111         cancel_delayed_work(&work);
 112         flush_scheduled_work();
 113         input_unregister_device(hp680_ts_dev);
 114 }
 115
 116 module_init(hp680_ts_init);
 117 module_exit(hp680_ts_exit);
 118
 119 MODULE_AUTHOR("Andriy Skulysh, askulysh@image.kiev.ua");
 120 MODULE_DESCRIPTION("HP Jornada 680 touchscreen driver");
 121 MODULE_LICENSE("GPL");