linux/drivers/input/touchscreen/88pm860x-ts.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Touchscreen driver for Marvell 88PM860x
   4 *
   5 * Copyright (C) 2009 Marvell International Ltd.
   6 *      Haojian Zhuang <haojian.zhuang@marvell.com>
   7 */
   8#include <linux/kernel.h>
   9#include <linux/module.h>
  10#include <linux/of.h>
  11#include <linux/platform_device.h>
  12#include <linux/i2c.h>
  13#include <linux/input.h>
  14#include <linux/mfd/88pm860x.h>
  15#include <linux/slab.h>
  16#include <linux/device.h>
  17
  18#define MEAS_LEN                (8)
  19#define ACCURATE_BIT            (12)
  20
  21/* touch register */
  22#define MEAS_EN3                (0x52)
  23
  24#define MEAS_TSIX_1             (0x8D)
  25#define MEAS_TSIX_2             (0x8E)
  26#define MEAS_TSIY_1             (0x8F)
  27#define MEAS_TSIY_2             (0x90)
  28#define MEAS_TSIZ1_1            (0x91)
  29#define MEAS_TSIZ1_2            (0x92)
  30#define MEAS_TSIZ2_1            (0x93)
  31#define MEAS_TSIZ2_2            (0x94)
  32
  33/* bit definitions of touch */
  34#define MEAS_PD_EN              (1 << 3)
  35#define MEAS_TSIX_EN            (1 << 4)
  36#define MEAS_TSIY_EN            (1 << 5)
  37#define MEAS_TSIZ1_EN           (1 << 6)
  38#define MEAS_TSIZ2_EN           (1 << 7)
  39
  40struct pm860x_touch {
  41        struct input_dev *idev;
  42        struct i2c_client *i2c;
  43        struct pm860x_chip *chip;
  44        int irq;
  45        int res_x;              /* resistor of Xplate */
  46};
  47
  48static irqreturn_t pm860x_touch_handler(int irq, void *data)
  49{
  50        struct pm860x_touch *touch = data;
  51        struct pm860x_chip *chip = touch->chip;
  52        unsigned char buf[MEAS_LEN];
  53        int x, y, pen_down;
  54        int z1, z2, rt = 0;
  55        int ret;
  56
  57        ret = pm860x_bulk_read(touch->i2c, MEAS_TSIX_1, MEAS_LEN, buf);
  58        if (ret < 0)
  59                goto out;
  60
  61        pen_down = buf[1] & (1 << 6);
  62        x = ((buf[0] & 0xFF) << 4) | (buf[1] & 0x0F);
  63        y = ((buf[2] & 0xFF) << 4) | (buf[3] & 0x0F);
  64        z1 = ((buf[4] & 0xFF) << 4) | (buf[5] & 0x0F);
  65        z2 = ((buf[6] & 0xFF) << 4) | (buf[7] & 0x0F);
  66
  67        if (pen_down) {
  68                if ((x != 0) && (z1 != 0) && (touch->res_x != 0)) {
  69                        rt = z2 / z1 - 1;
  70                        rt = (rt * touch->res_x * x) >> ACCURATE_BIT;
  71                        dev_dbg(chip->dev, "z1:%d, z2:%d, rt:%d\n",
  72                                z1, z2, rt);
  73                }
  74                input_report_abs(touch->idev, ABS_X, x);
  75                input_report_abs(touch->idev, ABS_Y, y);
  76                input_report_abs(touch->idev, ABS_PRESSURE, rt);
  77                input_report_key(touch->idev, BTN_TOUCH, 1);
  78                dev_dbg(chip->dev, "pen down at [%d, %d].\n", x, y);
  79        } else {
  80                input_report_abs(touch->idev, ABS_PRESSURE, 0);
  81                input_report_key(touch->idev, BTN_TOUCH, 0);
  82                dev_dbg(chip->dev, "pen release\n");
  83        }
  84        input_sync(touch->idev);
  85
  86out:
  87        return IRQ_HANDLED;
  88}
  89
  90static int pm860x_touch_open(struct input_dev *dev)
  91{
  92        struct pm860x_touch *touch = input_get_drvdata(dev);
  93        int data, ret;
  94
  95        data = MEAS_PD_EN | MEAS_TSIX_EN | MEAS_TSIY_EN
  96                | MEAS_TSIZ1_EN | MEAS_TSIZ2_EN;
  97        ret = pm860x_set_bits(touch->i2c, MEAS_EN3, data, data);
  98        if (ret < 0)
  99                goto out;
 100        return 0;
 101out:
 102        return ret;
 103}
 104
 105static void pm860x_touch_close(struct input_dev *dev)
 106{
 107        struct pm860x_touch *touch = input_get_drvdata(dev);
 108        int data;
 109
 110        data = MEAS_PD_EN | MEAS_TSIX_EN | MEAS_TSIY_EN
 111                | MEAS_TSIZ1_EN | MEAS_TSIZ2_EN;
 112        pm860x_set_bits(touch->i2c, MEAS_EN3, data, 0);
 113}
 114
 115#ifdef CONFIG_OF
 116static int pm860x_touch_dt_init(struct platform_device *pdev,
 117                                          struct pm860x_chip *chip,
 118                                          int *res_x)
 119{
 120        struct device_node *np = pdev->dev.parent->of_node;
 121        struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
 122                                 : chip->companion;
 123        int data, n, ret;
 124        if (!np)
 125                return -ENODEV;
 126        np = of_get_child_by_name(np, "touch");
 127        if (!np) {
 128                dev_err(&pdev->dev, "Can't find touch node\n");
 129                return -EINVAL;
 130        }
 131        /* set GPADC MISC1 register */
 132        data = 0;
 133        if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-prebias", &n))
 134                data |= (n << 1) & PM8607_GPADC_PREBIAS_MASK;
 135        if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-slot-cycle", &n))
 136                data |= (n << 3) & PM8607_GPADC_SLOT_CYCLE_MASK;
 137        if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-off-scale", &n))
 138                data |= (n << 5) & PM8607_GPADC_OFF_SCALE_MASK;
 139        if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-sw-cal", &n))
 140                data |= (n << 7) & PM8607_GPADC_SW_CAL_MASK;
 141        if (data) {
 142                ret = pm860x_reg_write(i2c, PM8607_GPADC_MISC1, data);
 143                if (ret < 0)
 144                        goto err_put_node;
 145        }
 146        /* set tsi prebias time */
 147        if (!of_property_read_u32(np, "marvell,88pm860x-tsi-prebias", &data)) {
 148                ret = pm860x_reg_write(i2c, PM8607_TSI_PREBIAS, data);
 149                if (ret < 0)
 150                        goto err_put_node;
 151        }
 152        /* set prebias & prechg time of pen detect */
 153        data = 0;
 154        if (!of_property_read_u32(np, "marvell,88pm860x-pen-prebias", &n))
 155                data |= n & PM8607_PD_PREBIAS_MASK;
 156        if (!of_property_read_u32(np, "marvell,88pm860x-pen-prechg", &n))
 157                data |= n & PM8607_PD_PRECHG_MASK;
 158        if (data) {
 159                ret = pm860x_reg_write(i2c, PM8607_PD_PREBIAS, data);
 160                if (ret < 0)
 161                        goto err_put_node;
 162        }
 163        of_property_read_u32(np, "marvell,88pm860x-resistor-X", res_x);
 164
 165        of_node_put(np);
 166
 167        return 0;
 168
 169err_put_node:
 170        of_node_put(np);
 171
 172        return -EINVAL;
 173}
 174#else
 175#define pm860x_touch_dt_init(x, y, z)   (-1)
 176#endif
 177
 178static int pm860x_touch_probe(struct platform_device *pdev)
 179{
 180        struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
 181        struct pm860x_touch_pdata *pdata = dev_get_platdata(&pdev->dev);
 182        struct pm860x_touch *touch;
 183        struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
 184                                 : chip->companion;
 185        int irq, ret, res_x = 0, data = 0;
 186
 187        irq = platform_get_irq(pdev, 0);
 188        if (irq < 0) {
 189                dev_err(&pdev->dev, "No IRQ resource!\n");
 190                return -EINVAL;
 191        }
 192
 193        if (pm860x_touch_dt_init(pdev, chip, &res_x)) {
 194                if (pdata) {
 195                        /* set GPADC MISC1 register */
 196                        data = 0;
 197                        data |= (pdata->gpadc_prebias << 1)
 198                                & PM8607_GPADC_PREBIAS_MASK;
 199                        data |= (pdata->slot_cycle << 3)
 200                                & PM8607_GPADC_SLOT_CYCLE_MASK;
 201                        data |= (pdata->off_scale << 5)
 202                                & PM8607_GPADC_OFF_SCALE_MASK;
 203                        data |= (pdata->sw_cal << 7)
 204                                & PM8607_GPADC_SW_CAL_MASK;
 205                        if (data) {
 206                                ret = pm860x_reg_write(i2c,
 207                                        PM8607_GPADC_MISC1, data);
 208                                if (ret < 0)
 209                                        return -EINVAL;
 210                        }
 211                        /* set tsi prebias time */
 212                        if (pdata->tsi_prebias) {
 213                                data = pdata->tsi_prebias;
 214                                ret = pm860x_reg_write(i2c,
 215                                        PM8607_TSI_PREBIAS, data);
 216                                if (ret < 0)
 217                                        return -EINVAL;
 218                        }
 219                        /* set prebias & prechg time of pen detect */
 220                        data = 0;
 221                        data |= pdata->pen_prebias
 222                                & PM8607_PD_PREBIAS_MASK;
 223                        data |= (pdata->pen_prechg << 5)
 224                                & PM8607_PD_PRECHG_MASK;
 225                        if (data) {
 226                                ret = pm860x_reg_write(i2c,
 227                                        PM8607_PD_PREBIAS, data);
 228                                if (ret < 0)
 229                                        return -EINVAL;
 230                        }
 231                        res_x = pdata->res_x;
 232                } else {
 233                        dev_err(&pdev->dev, "failed to get platform data\n");
 234                        return -EINVAL;
 235                }
 236        }
 237        /* enable GPADC */
 238        ret = pm860x_set_bits(i2c, PM8607_GPADC_MISC1, PM8607_GPADC_EN,
 239                              PM8607_GPADC_EN);
 240        if (ret)
 241                return ret;
 242
 243        touch = devm_kzalloc(&pdev->dev, sizeof(struct pm860x_touch),
 244                             GFP_KERNEL);
 245        if (!touch)
 246                return -ENOMEM;
 247
 248        touch->idev = devm_input_allocate_device(&pdev->dev);
 249        if (!touch->idev) {
 250                dev_err(&pdev->dev, "Failed to allocate input device!\n");
 251                return -ENOMEM;
 252        }
 253
 254        touch->idev->name = "88pm860x-touch";
 255        touch->idev->phys = "88pm860x/input0";
 256        touch->idev->id.bustype = BUS_I2C;
 257        touch->idev->dev.parent = &pdev->dev;
 258        touch->idev->open = pm860x_touch_open;
 259        touch->idev->close = pm860x_touch_close;
 260        touch->chip = chip;
 261        touch->i2c = i2c;
 262        touch->irq = irq;
 263        touch->res_x = res_x;
 264        input_set_drvdata(touch->idev, touch);
 265
 266        ret = devm_request_threaded_irq(&pdev->dev, touch->irq, NULL,
 267                                        pm860x_touch_handler, IRQF_ONESHOT,
 268                                        "touch", touch);
 269        if (ret < 0)
 270                return ret;
 271
 272        __set_bit(EV_ABS, touch->idev->evbit);
 273        __set_bit(ABS_X, touch->idev->absbit);
 274        __set_bit(ABS_Y, touch->idev->absbit);
 275        __set_bit(ABS_PRESSURE, touch->idev->absbit);
 276        __set_bit(EV_SYN, touch->idev->evbit);
 277        __set_bit(EV_KEY, touch->idev->evbit);
 278        __set_bit(BTN_TOUCH, touch->idev->keybit);
 279
 280        input_set_abs_params(touch->idev, ABS_X, 0, 1 << ACCURATE_BIT, 0, 0);
 281        input_set_abs_params(touch->idev, ABS_Y, 0, 1 << ACCURATE_BIT, 0, 0);
 282        input_set_abs_params(touch->idev, ABS_PRESSURE, 0, 1 << ACCURATE_BIT,
 283                                0, 0);
 284
 285        ret = input_register_device(touch->idev);
 286        if (ret < 0) {
 287                dev_err(chip->dev, "Failed to register touch!\n");
 288                return ret;
 289        }
 290
 291        return 0;
 292}
 293
 294static struct platform_driver pm860x_touch_driver = {
 295        .driver = {
 296                .name   = "88pm860x-touch",
 297        },
 298        .probe  = pm860x_touch_probe,
 299};
 300module_platform_driver(pm860x_touch_driver);
 301
 302MODULE_DESCRIPTION("Touchscreen driver for Marvell Semiconductor 88PM860x");
 303MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
 304MODULE_LICENSE("GPL");
 305MODULE_ALIAS("platform:88pm860x-touch");
 306
 307