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
  22 #include <mach/hardware.h>
  23 #include <mach/jornada720.h>
  24
  25 MODULE_AUTHOR("Kristoffer Ericson <kristoffer.ericson@gmail.com>");
  26 MODULE_DESCRIPTION("HP Jornada 710/720/728 touchscreen driver");
  27 MODULE_LICENSE("GPL v2");
  28
  29 struct jornada_ts {
  30         struct input_dev *dev;
  31         int x_data[4];          /* X sample values */
  32         int y_data[4];          /* Y sample values */
  33 };
  34
  35 static void jornada720_ts_collect_data(struct jornada_ts *jornada_ts)
  36 {
  37
  38     /* 3 low word X samples */
  39     jornada_ts->x_data[0] = jornada_ssp_byte(TXDUMMY);
  40     jornada_ts->x_data[1] = jornada_ssp_byte(TXDUMMY);
  41     jornada_ts->x_data[2] = jornada_ssp_byte(TXDUMMY);
  42
  43     /* 3 low word Y samples */
  44     jornada_ts->y_data[0] = jornada_ssp_byte(TXDUMMY);
  45     jornada_ts->y_data[1] = jornada_ssp_byte(TXDUMMY);
  46     jornada_ts->y_data[2] = jornada_ssp_byte(TXDUMMY);
  47
  48     /* combined x samples bits */
  49     jornada_ts->x_data[3] = jornada_ssp_byte(TXDUMMY);
  50
  51     /* combined y samples bits */
  52     jornada_ts->y_data[3] = jornada_ssp_byte(TXDUMMY);
  53 }
  54
  55 static int jornada720_ts_average(int coords[4])
  56 {
  57         int coord, high_bits = coords[3];
  58
  59         coord  = coords[0] | ((high_bits & 0x03) << 8);
  60         coord += coords[1] | ((high_bits & 0x0c) << 6);
  61         coord += coords[2] | ((high_bits & 0x30) << 4);
  62
  63         return coord / 3;
  64 }
  65
  66 static irqreturn_t jornada720_ts_interrupt(int irq, void *dev_id)
  67 {
  68         struct platform_device *pdev = dev_id;
  69         struct jornada_ts *jornada_ts = platform_get_drvdata(pdev);
  70         struct input_dev *input = jornada_ts->dev;
  71         int x, y;
  72
  73         /* If GPIO_GPIO9 is set to high then report pen up */
  74         if (GPLR & GPIO_GPIO(9)) {
  75                 input_report_key(input, BTN_TOUCH, 0);
  76                 input_sync(input);
  77         } else {
  78                 jornada_ssp_start();
  79
  80                 /* proper reply to request is always TXDUMMY */
  81                 if (jornada_ssp_inout(GETTOUCHSAMPLES) == TXDUMMY) {
  82                         jornada720_ts_collect_data(jornada_ts);
  83
  84                         x = jornada720_ts_average(jornada_ts->x_data);
  85                         y = jornada720_ts_average(jornada_ts->y_data);
  86
  87                         input_report_key(input, BTN_TOUCH, 1);
  88                         input_report_abs(input, ABS_X, x);
  89                         input_report_abs(input, ABS_Y, y);
  90                         input_sync(input);
  91                 }
  92
  93                 jornada_ssp_end();
  94         }
  95
  96         return IRQ_HANDLED;
  97 }
  98
  99 static int __devinit jornada720_ts_probe(struct platform_device *pdev)
 100 {
 101         struct jornada_ts *jornada_ts;
 102         struct input_dev *input_dev;
 103         int error;
 104
 105         jornada_ts = kzalloc(sizeof(struct jornada_ts), GFP_KERNEL);
 106         input_dev = input_allocate_device();
 107
 108         if (!jornada_ts || !input_dev) {
 109                 error = -ENOMEM;
 110                 goto fail1;
 111         }
 112
 113         platform_set_drvdata(pdev, jornada_ts);
 114
 115         jornada_ts->dev = input_dev;
 116
 117         input_dev->name = "HP Jornada 7xx Touchscreen";
 118         input_dev->phys = "jornadats/input0";
 119         input_dev->id.bustype = BUS_HOST;
 120         input_dev->dev.parent = &pdev->dev;
 121
 122         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 123         input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 124         input_set_abs_params(input_dev, ABS_X, 270, 3900, 0, 0);
 125         input_set_abs_params(input_dev, ABS_Y, 180, 3700, 0, 0);
 126
 127         error = request_irq(IRQ_GPIO9,
 128                         jornada720_ts_interrupt,
 129                         IRQF_DISABLED | IRQF_TRIGGER_RISING,
 130                         "HP7XX Touchscreen driver", pdev);
 131         if (error) {
 132                 printk(KERN_INFO "HP7XX TS : Unable to acquire irq!\n");
 133                 goto fail1;
 134         }
 135
 136         error = input_register_device(jornada_ts->dev);
 137         if (error)
 138                 goto fail2;
 139
 140         return 0;
 141
 142  fail2:
 143         free_irq(IRQ_GPIO9, pdev);
 144  fail1:
 145         platform_set_drvdata(pdev, NULL);
 146         input_free_device(input_dev);
 147         kfree(jornada_ts);
 148         return error;
 149 }
 150
 151 static int __devexit jornada720_ts_remove(struct platform_device *pdev)
 152 {
 153         struct jornada_ts *jornada_ts = platform_get_drvdata(pdev);
 154
 155         free_irq(IRQ_GPIO9, pdev);
 156         platform_set_drvdata(pdev, NULL);
 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         = __devexit_p(jornada720_ts_remove),
 169         .driver         = {
 170                 .name   = "jornada_ts",
 171                 .owner  = THIS_MODULE,
 172         },
 173 };
 174
 175 static int __init jornada720_ts_init(void)
 176 {
 177         return platform_driver_register(&jornada720_ts_driver);
 178 }
 179
 180 static void __exit jornada720_ts_exit(void)
 181 {
 182         platform_driver_unregister(&jornada720_ts_driver);
 183 }
 184
 185 module_init(jornada720_ts_init);
 186 module_exit(jornada720_ts_exit);