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

   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
  40 struct 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
  48 static 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
  86 out:
  87         return IRQ_HANDLED;
  88 }
  89
  90 static 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;
 101 out:
 102         return ret;
 103 }
 104
 105 static 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
 116 static int pm860x_touch_dt_init(struct platform_device *pdev,
 117                                           struct pm860x_chip *chip,
 118                                           int *res_x)
 119 {
 120         struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
 121                                  : chip->companion;
 122         int data, n, ret;
 123         if (!pdev->dev.parent->of_node)
 124                 return -ENODEV;
 125
 126         struct device_node *np __free(device_node) =
 127                 of_get_child_by_name(pdev->dev.parent->of_node, "touch");
 128         if (!np) {
 129                 dev_err(&pdev->dev, "Can't find touch node\n");
 130                 return -EINVAL;
 131         }
 132         /* set GPADC MISC1 register */
 133         data = 0;
 134         if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-prebias", &n))
 135                 data |= (n << 1) & PM8607_GPADC_PREBIAS_MASK;
 136         if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-slot-cycle", &n))
 137                 data |= (n << 3) & PM8607_GPADC_SLOT_CYCLE_MASK;
 138         if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-off-scale", &n))
 139                 data |= (n << 5) & PM8607_GPADC_OFF_SCALE_MASK;
 140         if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-sw-cal", &n))
 141                 data |= (n << 7) & PM8607_GPADC_SW_CAL_MASK;
 142         if (data) {
 143                 ret = pm860x_reg_write(i2c, PM8607_GPADC_MISC1, data);
 144                 if (ret < 0)
 145                         return -EINVAL;
 146         }
 147         /* set tsi prebias time */
 148         if (!of_property_read_u32(np, "marvell,88pm860x-tsi-prebias", &data)) {
 149                 ret = pm860x_reg_write(i2c, PM8607_TSI_PREBIAS, data);
 150                 if (ret < 0)
 151                         return -EINVAL;
 152         }
 153         /* set prebias & prechg time of pen detect */
 154         data = 0;
 155         if (!of_property_read_u32(np, "marvell,88pm860x-pen-prebias", &n))
 156                 data |= n & PM8607_PD_PREBIAS_MASK;
 157         if (!of_property_read_u32(np, "marvell,88pm860x-pen-prechg", &n))
 158                 data |= n & PM8607_PD_PRECHG_MASK;
 159         if (data) {
 160                 ret = pm860x_reg_write(i2c, PM8607_PD_PREBIAS, data);
 161                 if (ret < 0)
 162                         return -EINVAL;
 163         }
 164         of_property_read_u32(np, "marvell,88pm860x-resistor-X", res_x);
 165
 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 = dev_get_platdata(&pdev->dev);
 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                 return -EINVAL;
 184
 185         if (pm860x_touch_dt_init(pdev, chip, &res_x)) {
 186                 if (pdata) {
 187                         /* set GPADC MISC1 register */
 188                         data = 0;
 189                         data |= (pdata->gpadc_prebias << 1)
 190                                 & PM8607_GPADC_PREBIAS_MASK;
 191                         data |= (pdata->slot_cycle << 3)
 192                                 & PM8607_GPADC_SLOT_CYCLE_MASK;
 193                         data |= (pdata->off_scale << 5)
 194                                 & PM8607_GPADC_OFF_SCALE_MASK;
 195                         data |= (pdata->sw_cal << 7)
 196                                 & PM8607_GPADC_SW_CAL_MASK;
 197                         if (data) {
 198                                 ret = pm860x_reg_write(i2c,
 199                                         PM8607_GPADC_MISC1, data);
 200                                 if (ret < 0)
 201                                         return -EINVAL;
 202                         }
 203                         /* set tsi prebias time */
 204                         if (pdata->tsi_prebias) {
 205                                 data = pdata->tsi_prebias;
 206                                 ret = pm860x_reg_write(i2c,
 207                                         PM8607_TSI_PREBIAS, data);
 208                                 if (ret < 0)
 209                                         return -EINVAL;
 210                         }
 211                         /* set prebias & prechg time of pen detect */
 212                         data = 0;
 213                         data |= pdata->pen_prebias
 214                                 & PM8607_PD_PREBIAS_MASK;
 215                         data |= (pdata->pen_prechg << 5)
 216                                 & PM8607_PD_PRECHG_MASK;
 217                         if (data) {
 218                                 ret = pm860x_reg_write(i2c,
 219                                         PM8607_PD_PREBIAS, data);
 220                                 if (ret < 0)
 221                                         return -EINVAL;
 222                         }
 223                         res_x = pdata->res_x;
 224                 } else {
 225                         dev_err(&pdev->dev, "failed to get platform data\n");
 226                         return -EINVAL;
 227                 }
 228         }
 229         /* enable GPADC */
 230         ret = pm860x_set_bits(i2c, PM8607_GPADC_MISC1, PM8607_GPADC_EN,
 231                               PM8607_GPADC_EN);
 232         if (ret)
 233                 return ret;
 234
 235         touch = devm_kzalloc(&pdev->dev, sizeof(struct pm860x_touch),
 236                              GFP_KERNEL);
 237         if (!touch)
 238                 return -ENOMEM;
 239
 240         touch->idev = devm_input_allocate_device(&pdev->dev);
 241         if (!touch->idev) {
 242                 dev_err(&pdev->dev, "Failed to allocate input device!\n");
 243                 return -ENOMEM;
 244         }
 245
 246         touch->idev->name = "88pm860x-touch";
 247         touch->idev->phys = "88pm860x/input0";
 248         touch->idev->id.bustype = BUS_I2C;
 249         touch->idev->dev.parent = &pdev->dev;
 250         touch->idev->open = pm860x_touch_open;
 251         touch->idev->close = pm860x_touch_close;
 252         touch->chip = chip;
 253         touch->i2c = i2c;
 254         touch->irq = irq;
 255         touch->res_x = res_x;
 256         input_set_drvdata(touch->idev, touch);
 257
 258         ret = devm_request_threaded_irq(&pdev->dev, touch->irq, NULL,
 259                                         pm860x_touch_handler, IRQF_ONESHOT,
 260                                         "touch", touch);
 261         if (ret < 0)
 262                 return ret;
 263
 264         __set_bit(EV_ABS, touch->idev->evbit);
 265         __set_bit(ABS_X, touch->idev->absbit);
 266         __set_bit(ABS_Y, touch->idev->absbit);
 267         __set_bit(ABS_PRESSURE, touch->idev->absbit);
 268         __set_bit(EV_SYN, touch->idev->evbit);
 269         __set_bit(EV_KEY, touch->idev->evbit);
 270         __set_bit(BTN_TOUCH, touch->idev->keybit);
 271
 272         input_set_abs_params(touch->idev, ABS_X, 0, 1 << ACCURATE_BIT, 0, 0);
 273         input_set_abs_params(touch->idev, ABS_Y, 0, 1 << ACCURATE_BIT, 0, 0);
 274         input_set_abs_params(touch->idev, ABS_PRESSURE, 0, 1 << ACCURATE_BIT,
 275                                 0, 0);
 276
 277         ret = input_register_device(touch->idev);
 278         if (ret < 0) {
 279                 dev_err(chip->dev, "Failed to register touch!\n");
 280                 return ret;
 281         }
 282
 283         return 0;
 284 }
 285
 286 static struct platform_driver pm860x_touch_driver = {
 287         .driver = {
 288                 .name   = "88pm860x-touch",
 289         },
 290         .probe  = pm860x_touch_probe,
 291 };
 292 module_platform_driver(pm860x_touch_driver);
 293
 294 MODULE_DESCRIPTION("Touchscreen driver for Marvell Semiconductor 88PM860x");
 295 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
 296 MODULE_LICENSE("GPL");
 297 MODULE_ALIAS("platform:88pm860x-touch");
 298