drivers/input/touchscreen/jornada720_ts.c

   1 /*
   2  * drivers/input/touchscreen/jornada720_ts.c
   3  *
   4  * Copyright (C) 2007 Kristoffer Ericson <Kristoffer.Ericson@gmail.com>
   5  *
   6  *  Copyright (C) 2006 Filip Zyzniewski <filip.zyzniewski@tefnet.pl>
   7  *  based on HP Jornada 56x touchscreen driver by Alex Lange <chicken@handhelds.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  *
  13  * HP Jornada 710/720/729 Touchscreen Driver
  14  */
  15
  16 #include <linux/platform_device.h>
  17 #include <linux/input.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/module.h>
  20 #include <linux/slab.h>
  21 #include <linux/io.h>
  22
  23 #include <mach/hardware.h>
  24 #include <mach/jornada720.h>
  25 #include <mach/irqs.h>
  26
  27 MODULE_AUTHOR("Kristoffer Ericson <kristoffer.ericson@gmail.com>");
  28 MODULE_DESCRIPTION("HP Jornada 710/720/728 touchscreen driver");
  29 MODULE_LICENSE("GPL v2");
  30
  31 struct jornada_ts {
  32         struct input_dev *dev;
  33         int x_data[4];          /* X sample values */
  34         int y_data[4];          /* Y sample values */
  35 };
  36
  37 static void jornada720_ts_collect_data(struct jornada_ts *jornada_ts)
  38 {
  39
  40     /* 3 low word X samples */
  41     jornada_ts->x_data[0] = jornada_ssp_byte(TXDUMMY);
  42     jornada_ts->x_data[1] = jornada_ssp_byte(TXDUMMY);
  43     jornada_ts->x_data[2] = jornada_ssp_byte(TXDUMMY);
  44
  45     /* 3 low word Y samples */
  46     jornada_ts->y_data[0] = jornada_ssp_byte(TXDUMMY);
  47     jornada_ts->y_data[1] = jornada_ssp_byte(TXDUMMY);
  48     jornada_ts->y_data[2] = jornada_ssp_byte(TXDUMMY);
  49
  50     /* combined x samples bits */
  51     jornada_ts->x_data[3] = jornada_ssp_byte(TXDUMMY);
  52
  53     /* combined y samples bits */
  54     jornada_ts->y_data[3] = jornada_ssp_byte(TXDUMMY);
  55 }
  56
  57 static int jornada720_ts_average(int coords[4])
  58 {
  59         int coord, high_bits = coords[3];
  60
  61         coord  = coords[0] | ((high_bits & 0x03) << 8);
  62         coord += coords[1] | ((high_bits & 0x0c) << 6);
  63         coord += coords[2] | ((high_bits & 0x30) << 4);
  64
  65         return coord / 3;
  66 }
  67
  68 static irqreturn_t jornada720_ts_interrupt(int irq, void *dev_id)
  69 {
  70         struct platform_device *pdev = dev_id;
  71         struct jornada_ts *jornada_ts = platform_get_drvdata(pdev);
  72         struct input_dev *input = jornada_ts->dev;
  73         int x, y;
  74
  75         /* If GPIO_GPIO9 is set to high then report pen up */
  76         if (GPLR & GPIO_GPIO(9)) {
  77                 input_report_key(input, BTN_TOUCH, 0);
  78                 input_sync(input);
  79         } else {
  80                 jornada_ssp_start();
  81
  82                 /* proper reply to request is always TXDUMMY */
  83                 if (jornada_ssp_inout(GETTOUCHSAMPLES) == TXDUMMY) {
  84                         jornada720_ts_collect_data(jornada_ts);
  85
  86                         x = jornada720_ts_average(jornada_ts->x_data);
  87                         y = jornada720_ts_average(jornada_ts->y_data);
  88
  89                         input_report_key(input, BTN_TOUCH, 1);
  90                         input_report_abs(input, ABS_X, x);
  91                         input_report_abs(input, ABS_Y, y);
  92                         input_sync(input);
  93                 }
  94
  95                 jornada_ssp_end();
  96         }
  97
  98         return IRQ_HANDLED;
  99 }
 100
 101 static int jornada720_ts_probe(struct platform_device *pdev)
 102 {
 103         struct jornada_ts *jornada_ts;
 104         struct input_dev *input_dev;
 105         int error;
 106
 107         jornada_ts = kzalloc(sizeof(struct jornada_ts), GFP_KERNEL);
 108         input_dev = input_allocate_device();
 109
 110         if (!jornada_ts || !input_dev) {
 111                 error = -ENOMEM;
 112                 goto fail1;
 113         }
 114
 115         platform_set_drvdata(pdev, jornada_ts);
 116
 117         jornada_ts->dev = input_dev;
 118
 119         input_dev->name = "HP Jornada 7xx Touchscreen";
 120         input_dev->phys = "jornadats/input0";
 121         input_dev->id.bustype = BUS_HOST;
 122         input_dev->dev.parent = &pdev->dev;
 123
 124         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 125         input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 126         input_set_abs_params(input_dev, ABS_X, 270, 3900, 0, 0);
 127         input_set_abs_params(input_dev, ABS_Y, 180, 3700, 0, 0);
 128
 129         error = request_irq(IRQ_GPIO9,
 130                         jornada720_ts_interrupt,
 131                         IRQF_TRIGGER_RISING,
 132                         "HP7XX Touchscreen driver", pdev);
 133         if (error) {
 134                 printk(KERN_INFO "HP7XX TS : Unable to acquire irq!\n");
 135                 goto fail1;
 136         }
 137
 138         error = input_register_device(jornada_ts->dev);
 139         if (error)
 140                 goto fail2;
 141
 142         return 0;
 143
 144  fail2:
 145         free_irq(IRQ_GPIO9, pdev);
 146  fail1:
 147         input_free_device(input_dev);
 148         kfree(jornada_ts);
 149         return error;
 150 }
 151
 152 static int jornada720_ts_remove(struct platform_device *pdev)
 153 {
 154         struct jornada_ts *jornada_ts = platform_get_drvdata(pdev);
 155
 156         free_irq(IRQ_GPIO9, pdev);
 157         input_unregister_device(jornada_ts->dev);
 158         kfree(jornada_ts);
 159
 160         return 0;
 161 }
 162
 163 /* work with hotplug and coldplug */
 164 MODULE_ALIAS("platform:jornada_ts");
 165
 166 static struct platform_driver jornada720_ts_driver = {
 167         .probe          = jornada720_ts_probe,
 168         .remove         = jornada720_ts_remove,
 169         .driver         = {
 170                 .name   = "jornada_ts",
 171                 .owner  = THIS_MODULE,
 172         },
 173 };
 174 module_platform_driver(jornada720_ts_driver);