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/init.h>
  18 #include <linux/input.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/module.h>
  21 #include <linux/slab.h>
  22 #include <linux/io.h>
  23
  24 #include <mach/hardware.h>
  25 #include <mach/jornada720.h>
  26 #include <mach/irqs.h>
  27
  28 MODULE_AUTHOR("Kristoffer Ericson <kristoffer.ericson@gmail.com>");
  29 MODULE_DESCRIPTION("HP Jornada 710/720/728 touchscreen driver");
  30 MODULE_LICENSE("GPL v2");
  31
  32 struct jornada_ts {
  33         struct input_dev *dev;
  34         int x_data[4];          /* X sample values */
  35         int y_data[4];          /* Y sample values */
  36 };
  37
  38 static void jornada720_ts_collect_data(struct jornada_ts *jornada_ts)
  39 {
  40
  41     /* 3 low word X samples */
  42     jornada_ts->x_data[0] = jornada_ssp_byte(TXDUMMY);
  43     jornada_ts->x_data[1] = jornada_ssp_byte(TXDUMMY);
  44     jornada_ts->x_data[2] = jornada_ssp_byte(TXDUMMY);
  45
  46     /* 3 low word Y samples */
  47     jornada_ts->y_data[0] = jornada_ssp_byte(TXDUMMY);
  48     jornada_ts->y_data[1] = jornada_ssp_byte(TXDUMMY);
  49     jornada_ts->y_data[2] = jornada_ssp_byte(TXDUMMY);
  50
  51     /* combined x samples bits */
  52     jornada_ts->x_data[3] = jornada_ssp_byte(TXDUMMY);
  53
  54     /* combined y samples bits */
  55     jornada_ts->y_data[3] = jornada_ssp_byte(TXDUMMY);
  56 }
  57
  58 static int jornada720_ts_average(int coords[4])
  59 {
  60         int coord, high_bits = coords[3];
  61
  62         coord  = coords[0] | ((high_bits & 0x03) << 8);
  63         coord += coords[1] | ((high_bits & 0x0c) << 6);
  64         coord += coords[2] | ((high_bits & 0x30) << 4);
  65
  66         return coord / 3;
  67 }
  68
  69 static irqreturn_t jornada720_ts_interrupt(int irq, void *dev_id)
  70 {
  71         struct platform_device *pdev = dev_id;
  72         struct jornada_ts *jornada_ts = platform_get_drvdata(pdev);
  73         struct input_dev *input = jornada_ts->dev;
  74         int x, y;
  75
  76         /* If GPIO_GPIO9 is set to high then report pen up */
  77         if (GPLR & GPIO_GPIO(9)) {
  78                 input_report_key(input, BTN_TOUCH, 0);
  79                 input_sync(input);
  80         } else {
  81                 jornada_ssp_start();
  82
  83                 /* proper reply to request is always TXDUMMY */
  84                 if (jornada_ssp_inout(GETTOUCHSAMPLES) == TXDUMMY) {
  85                         jornada720_ts_collect_data(jornada_ts);
  86
  87                         x = jornada720_ts_average(jornada_ts->x_data);
  88                         y = jornada720_ts_average(jornada_ts->y_data);
  89
  90                         input_report_key(input, BTN_TOUCH, 1);
  91                         input_report_abs(input, ABS_X, x);
  92                         input_report_abs(input, ABS_Y, y);
  93                         input_sync(input);
  94                 }
  95
  96                 jornada_ssp_end();
  97         }
  98
  99         return IRQ_HANDLED;
 100 }
 101
 102 static int jornada720_ts_probe(struct platform_device *pdev)
 103 {
 104         struct jornada_ts *jornada_ts;
 105         struct input_dev *input_dev;
 106         int error;
 107
 108         jornada_ts = kzalloc(sizeof(struct jornada_ts), GFP_KERNEL);
 109         input_dev = input_allocate_device();
 110
 111         if (!jornada_ts || !input_dev) {
 112                 error = -ENOMEM;
 113                 goto fail1;
 114         }
 115
 116         platform_set_drvdata(pdev, jornada_ts);
 117
 118         jornada_ts->dev = input_dev;
 119
 120         input_dev->name = "HP Jornada 7xx Touchscreen";
 121         input_dev->phys = "jornadats/input0";
 122         input_dev->id.bustype = BUS_HOST;
 123         input_dev->dev.parent = &pdev->dev;
 124
 125         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 126         input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 127         input_set_abs_params(input_dev, ABS_X, 270, 3900, 0, 0);
 128         input_set_abs_params(input_dev, ABS_Y, 180, 3700, 0, 0);
 129
 130         error = request_irq(IRQ_GPIO9,
 131                         jornada720_ts_interrupt,
 132                         IRQF_TRIGGER_RISING,
 133                         "HP7XX Touchscreen driver", pdev);
 134         if (error) {
 135                 printk(KERN_INFO "HP7XX TS : Unable to acquire irq!\n");
 136                 goto fail1;
 137         }
 138
 139         error = input_register_device(jornada_ts->dev);
 140         if (error)
 141                 goto fail2;
 142
 143         return 0;
 144
 145  fail2:
 146         free_irq(IRQ_GPIO9, pdev);
 147  fail1:
 148         platform_set_drvdata(pdev, NULL);
 149         input_free_device(input_dev);
 150         kfree(jornada_ts);
 151         return error;
 152 }
 153
 154 static int jornada720_ts_remove(struct platform_device *pdev)
 155 {
 156         struct jornada_ts *jornada_ts = platform_get_drvdata(pdev);
 157
 158         free_irq(IRQ_GPIO9, pdev);
 159         platform_set_drvdata(pdev, NULL);
 160         input_unregister_device(jornada_ts->dev);
 161         kfree(jornada_ts);
 162
 163         return 0;
 164 }
 165
 166 /* work with hotplug and coldplug */
 167 MODULE_ALIAS("platform:jornada_ts");
 168
 169 static struct platform_driver jornada720_ts_driver = {
 170         .probe          = jornada720_ts_probe,
 171         .remove         = jornada720_ts_remove,
 172         .driver         = {
 173                 .name   = "jornada_ts",
 174                 .owner  = THIS_MODULE,
 175         },
 176 };
 177 module_platform_driver(jornada720_ts_driver);