drivers/input/touchscreen/hp680_ts_input.c

   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
  21 static void do_softint(struct work_struct *work);
  22
  23 static struct input_dev *hp680_ts_dev;
  24 static DECLARE_DELAYED_WORK(work, do_softint);
  25
  26 static 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
  69 static 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
  77 static 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
 116 static 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
 123 module_init(hp680_ts_init);
 124 module_exit(hp680_ts_exit);
 125
 126 MODULE_AUTHOR("Andriy Skulysh, [email protected]");
 127 MODULE_DESCRIPTION("HP Jornada 680 touchscreen driver");
 128 MODULE_LICENSE("GPL");