root/drivers/input/touchscreen/jornada720_ts.c

DEFINITIONS

1. jornada720_ts_collect_data
2. jornada720_ts_average
3. jornada720_ts_interrupt
4. jornada720_ts_probe

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * drivers/input/touchscreen/jornada720_ts.c
   4  *
   5  * Copyright (C) 2007 Kristoffer Ericson <Kristoffer.Ericson@gmail.com>
   6  *
   7  *  Copyright (C) 2006 Filip Zyzniewski <filip.zyzniewski@tefnet.pl>
   8  *  based on HP Jornada 56x touchscreen driver by Alex Lange <chicken@handhelds.org>
   9  *
  10  * HP Jornada 710/720/729 Touchscreen Driver
  11  */
  12 
  13 #include <linux/gpio/consumer.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/input.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/module.h>
  18 #include <linux/slab.h>
  19 #include <linux/io.h>
  20 
  21 #include <mach/jornada720.h>
  22 
  23 MODULE_AUTHOR("Kristoffer Ericson <kristoffer.ericson@gmail.com>");
  24 MODULE_DESCRIPTION("HP Jornada 710/720/728 touchscreen driver");
  25 MODULE_LICENSE("GPL v2");
  26 
  27 struct jornada_ts {
  28         struct input_dev *dev;
  29         struct gpio_desc *gpio;
  30         int x_data[4];          /* X sample values */
  31         int y_data[4];          /* Y sample values */
  32 };
  33 
  34 static void jornada720_ts_collect_data(struct jornada_ts *jornada_ts)
  35 {
  36         /* 3 low word X samples */
  37         jornada_ts->x_data[0] = jornada_ssp_byte(TXDUMMY);
  38         jornada_ts->x_data[1] = jornada_ssp_byte(TXDUMMY);
  39         jornada_ts->x_data[2] = jornada_ssp_byte(TXDUMMY);
  40 
  41         /* 3 low word Y samples */
  42         jornada_ts->y_data[0] = jornada_ssp_byte(TXDUMMY);
  43         jornada_ts->y_data[1] = jornada_ssp_byte(TXDUMMY);
  44         jornada_ts->y_data[2] = jornada_ssp_byte(TXDUMMY);
  45 
  46         /* combined x samples bits */
  47         jornada_ts->x_data[3] = jornada_ssp_byte(TXDUMMY);
  48 
  49         /* combined y samples bits */
  50         jornada_ts->y_data[3] = jornada_ssp_byte(TXDUMMY);
  51 }
  52 
  53 static int jornada720_ts_average(int coords[4])
  54 {
  55         int coord, high_bits = coords[3];
  56 
  57         coord  = coords[0] | ((high_bits & 0x03) << 8);
  58         coord += coords[1] | ((high_bits & 0x0c) << 6);
  59         coord += coords[2] | ((high_bits & 0x30) << 4);
  60 
  61         return coord / 3;
  62 }
  63 
  64 static irqreturn_t jornada720_ts_interrupt(int irq, void *dev_id)
  65 {
  66         struct platform_device *pdev = dev_id;
  67         struct jornada_ts *jornada_ts = platform_get_drvdata(pdev);
  68         struct input_dev *input = jornada_ts->dev;
  69         int x, y;
  70 
  71         /* If gpio is high then report pen up */
  72         if (gpiod_get_value(jornada_ts->gpio)) {
  73                 input_report_key(input, BTN_TOUCH, 0);
  74                 input_sync(input);
  75         } else {
  76                 jornada_ssp_start();
  77 
  78                 /* proper reply to request is always TXDUMMY */
  79                 if (jornada_ssp_inout(GETTOUCHSAMPLES) == TXDUMMY) {
  80                         jornada720_ts_collect_data(jornada_ts);
  81 
  82                         x = jornada720_ts_average(jornada_ts->x_data);
  83                         y = jornada720_ts_average(jornada_ts->y_data);
  84 
  85                         input_report_key(input, BTN_TOUCH, 1);
  86                         input_report_abs(input, ABS_X, x);
  87                         input_report_abs(input, ABS_Y, y);
  88                         input_sync(input);
  89                 }
  90 
  91                 jornada_ssp_end();
  92         }
  93 
  94         return IRQ_HANDLED;
  95 }
  96 
  97 static int jornada720_ts_probe(struct platform_device *pdev)
  98 {
  99         struct jornada_ts *jornada_ts;
 100         struct input_dev *input_dev;
 101         int error, irq;
 102 
 103         jornada_ts = devm_kzalloc(&pdev->dev, sizeof(*jornada_ts), GFP_KERNEL);
 104         if (!jornada_ts)
 105                 return -ENOMEM;
 106 
 107         input_dev = devm_input_allocate_device(&pdev->dev);
 108         if (!input_dev)
 109                 return -ENOMEM;
 110 
 111         platform_set_drvdata(pdev, jornada_ts);
 112 
 113         jornada_ts->gpio = devm_gpiod_get(&pdev->dev, "penup", GPIOD_IN);
 114         if (IS_ERR(jornada_ts->gpio))
 115                 return PTR_ERR(jornada_ts->gpio);
 116 
 117         irq = gpiod_to_irq(jornada_ts->gpio);
 118         if (irq <= 0)
 119                 return irq < 0 ? irq : -EINVAL;
 120 
 121         jornada_ts->dev = input_dev;
 122 
 123         input_dev->name = "HP Jornada 7xx Touchscreen";
 124         input_dev->phys = "jornadats/input0";
 125         input_dev->id.bustype = BUS_HOST;
 126         input_dev->dev.parent = &pdev->dev;
 127 
 128         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 129         input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
 130         input_set_abs_params(input_dev, ABS_X, 270, 3900, 0, 0);
 131         input_set_abs_params(input_dev, ABS_Y, 180, 3700, 0, 0);
 132 
 133         error = devm_request_irq(&pdev->dev, irq, jornada720_ts_interrupt,
 134                                  IRQF_TRIGGER_RISING,
 135                                  "HP7XX Touchscreen driver", pdev);
 136         if (error) {
 137                 dev_err(&pdev->dev, "HP7XX TS : Unable to acquire irq!\n");
 138                 return error;
 139         }
 140 
 141         error = input_register_device(jornada_ts->dev);
 142         if (error)
 143                 return error;
 144 
 145         return 0;
 146 }
 147 
 148 /* work with hotplug and coldplug */
 149 MODULE_ALIAS("platform:jornada_ts");
 150 
 151 static struct platform_driver jornada720_ts_driver = {
 152         .probe          = jornada720_ts_probe,
 153         .driver         = {
 154                 .name   = "jornada_ts",
 155         },
 156 };
 157 module_platform_driver(jornada720_ts_driver);