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/of.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/i2c.h>
  16 #include <linux/input.h>
  17 #include <linux/mfd/88pm860x.h>
  18 #include <linux/slab.h>
  19
  20 #define MEAS_LEN                (8)
  21 #define ACCURATE_BIT            (12)
  22
  23 /* touch register */
  24 #define MEAS_EN3                (0x52)
  25
  26 #define MEAS_TSIX_1             (0x8D)
  27 #define MEAS_TSIX_2             (0x8E)
  28 #define MEAS_TSIY_1             (0x8F)
  29 #define MEAS_TSIY_2             (0x90)
  30 #define MEAS_TSIZ1_1            (0x91)
  31 #define MEAS_TSIZ1_2            (0x92)
  32 #define MEAS_TSIZ2_1            (0x93)
  33 #define MEAS_TSIZ2_2            (0x94)
  34
  35 /* bit definitions of touch */
  36 #define MEAS_PD_EN              (1 << 3)
  37 #define MEAS_TSIX_EN            (1 << 4)
  38 #define MEAS_TSIY_EN            (1 << 5)
  39 #define MEAS_TSIZ1_EN           (1 << 6)
  40 #define MEAS_TSIZ2_EN           (1 << 7)
  41
  42 struct pm860x_touch {
  43         struct input_dev *idev;
  44         struct i2c_client *i2c;
  45         struct pm860x_chip *chip;
  46         int irq;
  47         int res_x;              /* resistor of Xplate */
  48 };
  49
  50 static irqreturn_t pm860x_touch_handler(int irq, void *data)
  51 {
  52         struct pm860x_touch *touch = data;
  53         struct pm860x_chip *chip = touch->chip;
  54         unsigned char buf[MEAS_LEN];
  55         int x, y, pen_down;
  56         int z1, z2, rt = 0;
  57         int ret;
  58
  59         ret = pm860x_bulk_read(touch->i2c, MEAS_TSIX_1, MEAS_LEN, buf);
  60         if (ret < 0)
  61                 goto out;
  62
  63         pen_down = buf[1] & (1 << 6);
  64         x = ((buf[0] & 0xFF) << 4) | (buf[1] & 0x0F);
  65         y = ((buf[2] & 0xFF) << 4) | (buf[3] & 0x0F);
  66         z1 = ((buf[4] & 0xFF) << 4) | (buf[5] & 0x0F);
  67         z2 = ((buf[6] & 0xFF) << 4) | (buf[7] & 0x0F);
  68
  69         if (pen_down) {
  70                 if ((x != 0) && (z1 != 0) && (touch->res_x != 0)) {
  71                         rt = z2 / z1 - 1;
  72                         rt = (rt * touch->res_x * x) >> ACCURATE_BIT;
  73                         dev_dbg(chip->dev, "z1:%d, z2:%d, rt:%d\n",
  74                                 z1, z2, rt);
  75                 }
  76                 input_report_abs(touch->idev, ABS_X, x);
  77                 input_report_abs(touch->idev, ABS_Y, y);
  78                 input_report_abs(touch->idev, ABS_PRESSURE, rt);
  79                 input_report_key(touch->idev, BTN_TOUCH, 1);
  80                 dev_dbg(chip->dev, "pen down at [%d, %d].\n", x, y);
  81         } else {
  82                 input_report_abs(touch->idev, ABS_PRESSURE, 0);
  83                 input_report_key(touch->idev, BTN_TOUCH, 0);
  84                 dev_dbg(chip->dev, "pen release\n");
  85         }
  86         input_sync(touch->idev);
  87
  88 out:
  89         return IRQ_HANDLED;
  90 }
  91
  92 static int pm860x_touch_open(struct input_dev *dev)
  93 {
  94         struct pm860x_touch *touch = input_get_drvdata(dev);
  95         int data, ret;
  96
  97         data = MEAS_PD_EN | MEAS_TSIX_EN | MEAS_TSIY_EN
  98                 | MEAS_TSIZ1_EN | MEAS_TSIZ2_EN;
  99         ret = pm860x_set_bits(touch->i2c, MEAS_EN3, data, data);
 100         if (ret < 0)
 101                 goto out;
 102         return 0;
 103 out:
 104         return ret;
 105 }
 106
 107 static void pm860x_touch_close(struct input_dev *dev)
 108 {
 109         struct pm860x_touch *touch = input_get_drvdata(dev);
 110         int data;
 111
 112         data = MEAS_PD_EN | MEAS_TSIX_EN | MEAS_TSIY_EN
 113                 | MEAS_TSIZ1_EN | MEAS_TSIZ2_EN;
 114         pm860x_set_bits(touch->i2c, MEAS_EN3, data, 0);
 115 }
 116
 117 #ifdef CONFIG_OF
 118 static int pm860x_touch_dt_init(struct platform_device *pdev,
 119                                           struct pm860x_chip *chip,
 120                                           int *res_x)
 121 {
 122         struct device_node *np = pdev->dev.parent->of_node;
 123         struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
 124                                  : chip->companion;
 125         int data, n, ret;
 126         if (!np)
 127                 return -ENODEV;
 128         np = of_find_node_by_name(np, "touch");
 129         if (!np) {
 130                 dev_err(&pdev->dev, "Can't find touch node\n");
 131                 return -EINVAL;
 132         }
 133         /* set GPADC MISC1 register */
 134         data = 0;
 135         if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-prebias", &n))
 136                 data |= (n << 1) & PM8607_GPADC_PREBIAS_MASK;
 137         if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-slot-cycle", &n))
 138                 data |= (n << 3) & PM8607_GPADC_SLOT_CYCLE_MASK;
 139         if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-off-scale", &n))
 140                 data |= (n << 5) & PM8607_GPADC_OFF_SCALE_MASK;
 141         if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-sw-cal", &n))
 142                 data |= (n << 7) & PM8607_GPADC_SW_CAL_MASK;
 143         if (data) {
 144                 ret = pm860x_reg_write(i2c, PM8607_GPADC_MISC1, data);
 145                 if (ret < 0)
 146                         return -EINVAL;
 147         }
 148         /* set tsi prebias time */
 149         if (!of_property_read_u32(np, "marvell,88pm860x-tsi-prebias", &data)) {
 150                 ret = pm860x_reg_write(i2c, PM8607_TSI_PREBIAS, data);
 151                 if (ret < 0)
 152                         return -EINVAL;
 153         }
 154         /* set prebias & prechg time of pen detect */
 155         data = 0;
 156         if (!of_property_read_u32(np, "marvell,88pm860x-pen-prebias", &n))
 157                 data |= n & PM8607_PD_PREBIAS_MASK;
 158         if (!of_property_read_u32(np, "marvell,88pm860x-pen-prechg", &n))
 159                 data |= n & PM8607_PD_PRECHG_MASK;
 160         if (data) {
 161                 ret = pm860x_reg_write(i2c, PM8607_PD_PREBIAS, data);
 162                 if (ret < 0)
 163                         return -EINVAL;
 164         }
 165         of_property_read_u32(np, "marvell,88pm860x-resistor-X", res_x);
 166         return 0;
 167 }
 168 #else
 169 #define pm860x_touch_dt_init(x, y, z)   (-1)
 170 #endif
 171
 172 static int pm860x_touch_probe(struct platform_device *pdev)
 173 {
 174         struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
 175         struct pm860x_touch_pdata *pdata = pdev->dev.platform_data;
 176         struct pm860x_touch *touch;
 177         struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
 178                                  : chip->companion;
 179         int irq, ret, res_x = 0, data = 0;
 180
 181         irq = platform_get_irq(pdev, 0);
 182         if (irq < 0) {
 183                 dev_err(&pdev->dev, "No IRQ resource!\n");
 184                 return -EINVAL;
 185         }
 186
 187         if (pm860x_touch_dt_init(pdev, chip, &res_x)) {
 188                 if (pdata) {
 189                         /* set GPADC MISC1 register */
 190                         data = 0;
 191                         data |= (pdata->gpadc_prebias << 1)
 192                                 & PM8607_GPADC_PREBIAS_MASK;
 193                         data |= (pdata->slot_cycle << 3)
 194                                 & PM8607_GPADC_SLOT_CYCLE_MASK;
 195                         data |= (pdata->off_scale << 5)
 196                                 & PM8607_GPADC_OFF_SCALE_MASK;
 197                         data |= (pdata->sw_cal << 7)
 198                                 & PM8607_GPADC_SW_CAL_MASK;
 199                         if (data) {
 200                                 ret = pm860x_reg_write(i2c,
 201                                         PM8607_GPADC_MISC1, data);
 202                                 if (ret < 0)
 203                                         return -EINVAL;
 204                         }
 205                         /* set tsi prebias time */
 206                         if (pdata->tsi_prebias) {
 207                                 data = pdata->tsi_prebias;
 208                                 ret = pm860x_reg_write(i2c,
 209                                         PM8607_TSI_PREBIAS, data);
 210                                 if (ret < 0)
 211                                         return -EINVAL;
 212                         }
 213                         /* set prebias & prechg time of pen detect */
 214                         data = 0;
 215                         data |= pdata->pen_prebias
 216                                 & PM8607_PD_PREBIAS_MASK;
 217                         data |= (pdata->pen_prechg << 5)
 218                                 & PM8607_PD_PRECHG_MASK;
 219                         if (data) {
 220                                 ret = pm860x_reg_write(i2c,
 221                                         PM8607_PD_PREBIAS, data);
 222                                 if (ret < 0)
 223                                         return -EINVAL;
 224                         }
 225                         res_x = pdata->res_x;
 226                 } else {
 227                         dev_err(&pdev->dev, "failed to get platform data\n");
 228                         return -EINVAL;
 229                 }
 230         }
 231         /* enable GPADC */
 232         ret = pm860x_set_bits(i2c, PM8607_GPADC_MISC1, PM8607_GPADC_EN,
 233                               PM8607_GPADC_EN);
 234         if (ret)
 235                 return ret;
 236
 237         touch = kzalloc(sizeof(struct pm860x_touch), GFP_KERNEL);
 238         if (touch == NULL)
 239                 return -ENOMEM;
 240         platform_set_drvdata(pdev, touch);
 241
 242         touch->idev = input_allocate_device();
 243         if (touch->idev == NULL) {
 244                 dev_err(&pdev->dev, "Failed to allocate input device!\n");
 245                 ret = -ENOMEM;
 246                 goto out;
 247         }
 248
 249         touch->idev->name = "88pm860x-touch";
 250         touch->idev->phys = "88pm860x/input0";
 251         touch->idev->id.bustype = BUS_I2C;
 252         touch->idev->dev.parent = &pdev->dev;
 253         touch->idev->open = pm860x_touch_open;
 254         touch->idev->close = pm860x_touch_close;
 255         touch->chip = chip;
 256         touch->i2c = i2c;
 257         touch->irq = irq;
 258         touch->res_x = res_x;
 259         input_set_drvdata(touch->idev, touch);
 260
 261         ret = request_threaded_irq(touch->irq, NULL, pm860x_touch_handler,
 262                                    IRQF_ONESHOT, "touch", touch);
 263         if (ret < 0)
 264                 goto out_irq;
 265
 266         __set_bit(EV_ABS, touch->idev->evbit);
 267         __set_bit(ABS_X, touch->idev->absbit);
 268         __set_bit(ABS_Y, touch->idev->absbit);
 269         __set_bit(ABS_PRESSURE, touch->idev->absbit);
 270         __set_bit(EV_SYN, touch->idev->evbit);
 271         __set_bit(EV_KEY, touch->idev->evbit);
 272         __set_bit(BTN_TOUCH, touch->idev->keybit);
 273
 274         input_set_abs_params(touch->idev, ABS_X, 0, 1 << ACCURATE_BIT, 0, 0);
 275         input_set_abs_params(touch->idev, ABS_Y, 0, 1 << ACCURATE_BIT, 0, 0);
 276         input_set_abs_params(touch->idev, ABS_PRESSURE, 0, 1 << ACCURATE_BIT,
 277                                 0, 0);
 278
 279         ret = input_register_device(touch->idev);
 280         if (ret < 0) {
 281                 dev_err(chip->dev, "Failed to register touch!\n");
 282                 goto out_rg;
 283         }
 284
 285         platform_set_drvdata(pdev, touch);
 286         return 0;
 287 out_rg:
 288         free_irq(touch->irq, touch);
 289 out_irq:
 290         input_free_device(touch->idev);
 291 out:
 292         kfree(touch);
 293         return ret;
 294 }
 295
 296 static int pm860x_touch_remove(struct platform_device *pdev)
 297 {
 298         struct pm860x_touch *touch = platform_get_drvdata(pdev);
 299
 300         input_unregister_device(touch->idev);
 301         free_irq(touch->irq, touch);
 302         kfree(touch);
 303         return 0;
 304 }
 305
 306 static struct platform_driver pm860x_touch_driver = {
 307         .driver = {
 308                 .name   = "88pm860x-touch",
 309                 .owner  = THIS_MODULE,
 310         },
 311         .probe  = pm860x_touch_probe,
 312         .remove = pm860x_touch_remove,
 313 };
 314 module_platform_driver(pm860x_touch_driver);
 315
 316 MODULE_DESCRIPTION("Touchscreen driver for Marvell Semiconductor 88PM860x");
 317 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
 318 MODULE_LICENSE("GPL");
 319 MODULE_ALIAS("platform:88pm860x-touch");
 320