drivers/input/touchscreen/88pm860x-ts.c

   1 /*
   2  * Touchscreen driver for Marvell 88PM860x
   3  *
   4  * Copyright (C) 2009 Marvell International Ltd.
   5  *      Haojian Zhuang <haojian.zhuang@marvell.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/i2c.h>
  15 #include <linux/input.h>
  16 #include <linux/mfd/88pm860x.h>
  17 #include <linux/slab.h>
  18
  19 #define MEAS_LEN                (8)
  20 #define ACCURATE_BIT            (12)
  21
  22 /* touch register */
  23 #define MEAS_EN3                (0x52)
  24
  25 #define MEAS_TSIX_1             (0x8D)
  26 #define MEAS_TSIX_2             (0x8E)
  27 #define MEAS_TSIY_1             (0x8F)
  28 #define MEAS_TSIY_2             (0x90)
  29 #define MEAS_TSIZ1_1            (0x91)
  30 #define MEAS_TSIZ1_2            (0x92)
  31 #define MEAS_TSIZ2_1            (0x93)
  32 #define MEAS_TSIZ2_2            (0x94)
  33
  34 /* bit definitions of touch */
  35 #define MEAS_PD_EN              (1 << 3)
  36 #define MEAS_TSIX_EN            (1 << 4)
  37 #define MEAS_TSIY_EN            (1 << 5)
  38 #define MEAS_TSIZ1_EN           (1 << 6)
  39 #define MEAS_TSIZ2_EN           (1 << 7)
  40
  41 struct pm860x_touch {
  42         struct input_dev *idev;
  43         struct i2c_client *i2c;
  44         struct pm860x_chip *chip;
  45         int irq;
  46         int res_x;              /* resistor of Xplate */
  47 };
  48
  49 static irqreturn_t pm860x_touch_handler(int irq, void *data)
  50 {
  51         struct pm860x_touch *touch = data;
  52         struct pm860x_chip *chip = touch->chip;
  53         unsigned char buf[MEAS_LEN];
  54         int x, y, pen_down;
  55         int z1, z2, rt = 0;
  56         int ret;
  57
  58         ret = pm860x_bulk_read(touch->i2c, MEAS_TSIX_1, MEAS_LEN, buf);
  59         if (ret < 0)
  60                 goto out;
  61
  62         pen_down = buf[1] & (1 << 6);
  63         x = ((buf[0] & 0xFF) << 4) | (buf[1] & 0x0F);
  64         y = ((buf[2] & 0xFF) << 4) | (buf[3] & 0x0F);
  65         z1 = ((buf[4] & 0xFF) << 4) | (buf[5] & 0x0F);
  66         z2 = ((buf[6] & 0xFF) << 4) | (buf[7] & 0x0F);
  67
  68         if (pen_down) {
  69                 if ((x != 0) && (z1 != 0) && (touch->res_x != 0)) {
  70                         rt = z2 / z1 - 1;
  71                         rt = (rt * touch->res_x * x) >> ACCURATE_BIT;
  72                         dev_dbg(chip->dev, "z1:%d, z2:%d, rt:%d\n",
  73                                 z1, z2, rt);
  74                 }
  75                 input_report_abs(touch->idev, ABS_X, x);
  76                 input_report_abs(touch->idev, ABS_Y, y);
  77                 input_report_abs(touch->idev, ABS_PRESSURE, rt);
  78                 input_report_key(touch->idev, BTN_TOUCH, 1);
  79                 dev_dbg(chip->dev, "pen down at [%d, %d].\n", x, y);
  80         } else {
  81                 input_report_abs(touch->idev, ABS_PRESSURE, 0);
  82                 input_report_key(touch->idev, BTN_TOUCH, 0);
  83                 dev_dbg(chip->dev, "pen release\n");
  84         }
  85         input_sync(touch->idev);
  86
  87 out:
  88         return IRQ_HANDLED;
  89 }
  90
  91 static int pm860x_touch_open(struct input_dev *dev)
  92 {
  93         struct pm860x_touch *touch = input_get_drvdata(dev);
  94         int data, ret;
  95
  96         data = MEAS_PD_EN | MEAS_TSIX_EN | MEAS_TSIY_EN
  97                 | MEAS_TSIZ1_EN | MEAS_TSIZ2_EN;
  98         ret = pm860x_set_bits(touch->i2c, MEAS_EN3, data, data);
  99         if (ret < 0)
 100                 goto out;
 101         return 0;
 102 out:
 103         return ret;
 104 }
 105
 106 static void pm860x_touch_close(struct input_dev *dev)
 107 {
 108         struct pm860x_touch *touch = input_get_drvdata(dev);
 109         int data;
 110
 111         data = MEAS_PD_EN | MEAS_TSIX_EN | MEAS_TSIY_EN
 112                 | MEAS_TSIZ1_EN | MEAS_TSIZ2_EN;
 113         pm860x_set_bits(touch->i2c, MEAS_EN3, data, 0);
 114 }
 115
 116 static int __devinit pm860x_touch_probe(struct platform_device *pdev)
 117 {
 118         struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
 119         struct pm860x_platform_data *pm860x_pdata =             \
 120                                 pdev->dev.parent->platform_data;
 121         struct pm860x_touch_pdata *pdata = NULL;
 122         struct pm860x_touch *touch;
 123         int irq, ret;
 124
 125         irq = platform_get_irq(pdev, 0);
 126         if (irq < 0) {
 127                 dev_err(&pdev->dev, "No IRQ resource!\n");
 128                 return -EINVAL;
 129         }
 130
 131         if (!pm860x_pdata) {
 132                 dev_err(&pdev->dev, "platform data is missing\n");
 133                 return -EINVAL;
 134         }
 135
 136         pdata = pm860x_pdata->touch;
 137         if (!pdata) {
 138                 dev_err(&pdev->dev, "touchscreen data is missing\n");
 139                 return -EINVAL;
 140         }
 141
 142         touch = kzalloc(sizeof(struct pm860x_touch), GFP_KERNEL);
 143         if (touch == NULL)
 144                 return -ENOMEM;
 145         dev_set_drvdata(&pdev->dev, touch);
 146
 147         touch->idev = input_allocate_device();
 148         if (touch->idev == NULL) {
 149                 dev_err(&pdev->dev, "Failed to allocate input device!\n");
 150                 ret = -ENOMEM;
 151                 goto out;
 152         }
 153
 154         touch->idev->name = "88pm860x-touch";
 155         touch->idev->phys = "88pm860x/input0";
 156         touch->idev->id.bustype = BUS_I2C;
 157         touch->idev->dev.parent = &pdev->dev;
 158         touch->idev->open = pm860x_touch_open;
 159         touch->idev->close = pm860x_touch_close;
 160         touch->chip = chip;
 161         touch->i2c = (chip->id == CHIP_PM8607) ? chip->client : chip->companion;
 162         touch->irq = irq + chip->irq_base;
 163         touch->res_x = pdata->res_x;
 164         input_set_drvdata(touch->idev, touch);
 165
 166         ret = request_threaded_irq(touch->irq, NULL, pm860x_touch_handler,
 167                                    IRQF_ONESHOT, "touch", touch);
 168         if (ret < 0)
 169                 goto out_irq;
 170
 171         __set_bit(EV_ABS, touch->idev->evbit);
 172         __set_bit(ABS_X, touch->idev->absbit);
 173         __set_bit(ABS_Y, touch->idev->absbit);
 174         __set_bit(ABS_PRESSURE, touch->idev->absbit);
 175         __set_bit(EV_SYN, touch->idev->evbit);
 176         __set_bit(EV_KEY, touch->idev->evbit);
 177         __set_bit(BTN_TOUCH, touch->idev->keybit);
 178
 179         input_set_abs_params(touch->idev, ABS_X, 0, 1 << ACCURATE_BIT, 0, 0);
 180         input_set_abs_params(touch->idev, ABS_Y, 0, 1 << ACCURATE_BIT, 0, 0);
 181         input_set_abs_params(touch->idev, ABS_PRESSURE, 0, 1 << ACCURATE_BIT,
 182                                 0, 0);
 183
 184         ret = input_register_device(touch->idev);
 185         if (ret < 0) {
 186                 dev_err(chip->dev, "Failed to register touch!\n");
 187                 goto out_rg;
 188         }
 189
 190         platform_set_drvdata(pdev, touch);
 191         return 0;
 192 out_rg:
 193         free_irq(touch->irq, touch);
 194 out_irq:
 195         input_free_device(touch->idev);
 196 out:
 197         kfree(touch);
 198         return ret;
 199 }
 200
 201 static int __devexit pm860x_touch_remove(struct platform_device *pdev)
 202 {
 203         struct pm860x_touch *touch = platform_get_drvdata(pdev);
 204
 205         input_unregister_device(touch->idev);
 206         free_irq(touch->irq, touch);
 207         platform_set_drvdata(pdev, NULL);
 208         kfree(touch);
 209         return 0;
 210 }
 211
 212 static struct platform_driver pm860x_touch_driver = {
 213         .driver = {
 214                 .name   = "88pm860x-touch",
 215                 .owner  = THIS_MODULE,
 216         },
 217         .probe  = pm860x_touch_probe,
 218         .remove = __devexit_p(pm860x_touch_remove),
 219 };
 220 module_platform_driver(pm860x_touch_driver);
 221
 222 MODULE_DESCRIPTION("Touchscreen driver for Marvell Semiconductor 88PM860x");
 223 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
 224 MODULE_LICENSE("GPL");
 225 MODULE_ALIAS("platform:88pm860x-touch");
 226