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