LXR linux/drivers/input/touchscreen/jornada720

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