drivers/input/touchscreen/hp680_ts_input.c

   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");