root/drivers/input/misc/drv2667.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * DRV2667 haptics driver family
 *
 * Author: Dan Murphy <dmurphy@ti.com>
 *
 * Copyright: (C) 2014 Texas Instruments, Inc.
 */

#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/regulator/consumer.h>

/* Control registers */
#define DRV2667_STATUS  0x00
#define DRV2667_CTRL_1  0x01
#define DRV2667_CTRL_2  0x02
/* Waveform sequencer */
#define DRV2667_WV_SEQ_0        0x03
#define DRV2667_WV_SEQ_1        0x04
#define DRV2667_WV_SEQ_2        0x05
#define DRV2667_WV_SEQ_3        0x06
#define DRV2667_WV_SEQ_4        0x07
#define DRV2667_WV_SEQ_5        0x08
#define DRV2667_WV_SEQ_6        0x09
#define DRV2667_WV_SEQ_7        0x0A
#define DRV2667_FIFO            0x0B
#define DRV2667_PAGE            0xFF
#define DRV2667_MAX_REG         DRV2667_PAGE

#define DRV2667_PAGE_0          0x00
#define DRV2667_PAGE_1          0x01
#define DRV2667_PAGE_2          0x02
#define DRV2667_PAGE_3          0x03
#define DRV2667_PAGE_4          0x04
#define DRV2667_PAGE_5          0x05
#define DRV2667_PAGE_6          0x06
#define DRV2667_PAGE_7          0x07
#define DRV2667_PAGE_8          0x08

/* RAM fields */
#define DRV2667_RAM_HDR_SZ      0x0
/* RAM Header addresses */
#define DRV2667_RAM_START_HI    0x01
#define DRV2667_RAM_START_LO    0x02
#define DRV2667_RAM_STOP_HI             0x03
#define DRV2667_RAM_STOP_LO             0x04
#define DRV2667_RAM_REPEAT_CT   0x05
/* RAM data addresses */
#define DRV2667_RAM_AMP         0x06
#define DRV2667_RAM_FREQ        0x07
#define DRV2667_RAM_DURATION    0x08
#define DRV2667_RAM_ENVELOPE    0x09

/* Control 1 Register */
#define DRV2667_25_VPP_GAIN             0x00
#define DRV2667_50_VPP_GAIN             0x01
#define DRV2667_75_VPP_GAIN             0x02
#define DRV2667_100_VPP_GAIN    0x03
#define DRV2667_DIGITAL_IN              0xfc
#define DRV2667_ANALOG_IN               (1 << 2)

/* Control 2 Register */
#define DRV2667_GO                      (1 << 0)
#define DRV2667_STANDBY         (1 << 6)
#define DRV2667_DEV_RST         (1 << 7)

/* RAM Envelope settings */
#define DRV2667_NO_ENV                  0x00
#define DRV2667_32_MS_ENV               0x01
#define DRV2667_64_MS_ENV               0x02
#define DRV2667_96_MS_ENV               0x03
#define DRV2667_128_MS_ENV              0x04
#define DRV2667_160_MS_ENV              0x05
#define DRV2667_192_MS_ENV              0x06
#define DRV2667_224_MS_ENV              0x07
#define DRV2667_256_MS_ENV              0x08
#define DRV2667_512_MS_ENV              0x09
#define DRV2667_768_MS_ENV              0x0a
#define DRV2667_1024_MS_ENV             0x0b
#define DRV2667_1280_MS_ENV             0x0c
#define DRV2667_1536_MS_ENV             0x0d
#define DRV2667_1792_MS_ENV             0x0e
#define DRV2667_2048_MS_ENV             0x0f

/**
 * struct drv2667_data -
 * @input_dev: Pointer to the input device
 * @client: Pointer to the I2C client
 * @regmap: Register map of the device
 * @work: Work item used to off load the enable/disable of the vibration
 * @regulator: Pointer to the regulator for the IC
 * @page: Page number
 * @magnitude: Magnitude of the vibration event
 * @frequency: Frequency of the vibration event
**/
struct drv2667_data {
        struct input_dev *input_dev;
        struct i2c_client *client;
        struct regmap *regmap;
        struct work_struct work;
        struct regulator *regulator;
        u32 page;
        u32 magnitude;
        u32 frequency;
};

static const struct reg_default drv2667_reg_defs[] = {
        { DRV2667_STATUS, 0x02 },
        { DRV2667_CTRL_1, 0x28 },
        { DRV2667_CTRL_2, 0x40 },
        { DRV2667_WV_SEQ_0, 0x00 },
        { DRV2667_WV_SEQ_1, 0x00 },
        { DRV2667_WV_SEQ_2, 0x00 },
        { DRV2667_WV_SEQ_3, 0x00 },
        { DRV2667_WV_SEQ_4, 0x00 },
        { DRV2667_WV_SEQ_5, 0x00 },
        { DRV2667_WV_SEQ_6, 0x00 },
        { DRV2667_WV_SEQ_7, 0x00 },
        { DRV2667_FIFO, 0x00 },
        { DRV2667_PAGE, 0x00 },
};

static int drv2667_set_waveform_freq(struct drv2667_data *haptics)
{
        unsigned int read_buf;
        int freq;
        int error;

        /* Per the data sheet:
         * Sinusoid Frequency (Hz) = 7.8125 x Frequency
         */
        freq = (haptics->frequency * 1000) / 78125;
        if (freq <= 0) {
                dev_err(&haptics->client->dev,
                        "ERROR: Frequency calculated to %i\n", freq);
                return -EINVAL;
        }

        error = regmap_read(haptics->regmap, DRV2667_PAGE, &read_buf);
        if (error) {
                dev_err(&haptics->client->dev,
                        "Failed to read the page number: %d\n", error);
                return -EIO;
        }

        if (read_buf == DRV2667_PAGE_0 ||
                haptics->page != read_buf) {
                error = regmap_write(haptics->regmap,
                                DRV2667_PAGE, haptics->page);
                if (error) {
                        dev_err(&haptics->client->dev,
                                "Failed to set the page: %d\n", error);
                        return -EIO;
                }
        }

        error = regmap_write(haptics->regmap, DRV2667_RAM_FREQ, freq);
        if (error)
                dev_err(&haptics->client->dev,
                                "Failed to set the frequency: %d\n", error);

        /* Reset back to original page */
        if (read_buf == DRV2667_PAGE_0 ||
                haptics->page != read_buf) {
                error = regmap_write(haptics->regmap, DRV2667_PAGE, read_buf);
                if (error) {
                        dev_err(&haptics->client->dev,
                                "Failed to set the page: %d\n", error);
                        return -EIO;
                }
        }

        return error;
}

static void drv2667_worker(struct work_struct *work)
{
        struct drv2667_data *haptics = container_of(work, struct drv2667_data, work);
        int error;

        if (haptics->magnitude) {
                error = regmap_write(haptics->regmap,
                                DRV2667_PAGE, haptics->page);
                if (error) {
                        dev_err(&haptics->client->dev,
                                "Failed to set the page: %d\n", error);
                        return;
                }

                error = regmap_write(haptics->regmap, DRV2667_RAM_AMP,
                                haptics->magnitude);
                if (error) {
                        dev_err(&haptics->client->dev,
                                "Failed to set the amplitude: %d\n", error);
                        return;
                }

                error = regmap_write(haptics->regmap,
                                DRV2667_PAGE, DRV2667_PAGE_0);
                if (error) {
                        dev_err(&haptics->client->dev,
                                "Failed to set the page: %d\n", error);
                        return;
                }

                error = regmap_write(haptics->regmap,
                                DRV2667_CTRL_2, DRV2667_GO);
                if (error) {
                        dev_err(&haptics->client->dev,
                                "Failed to set the GO bit: %d\n", error);
                }
        } else {
                error = regmap_update_bits(haptics->regmap, DRV2667_CTRL_2,
                                DRV2667_GO, 0);
                if (error) {
                        dev_err(&haptics->client->dev,
                                "Failed to unset the GO bit: %d\n", error);
                }
        }
}

static int drv2667_haptics_play(struct input_dev *input, void *data,
                                struct ff_effect *effect)
{
        struct drv2667_data *haptics = input_get_drvdata(input);

        if (effect->u.rumble.strong_magnitude > 0)
                haptics->magnitude = effect->u.rumble.strong_magnitude;
        else if (effect->u.rumble.weak_magnitude > 0)
                haptics->magnitude = effect->u.rumble.weak_magnitude;
        else
                haptics->magnitude = 0;

        schedule_work(&haptics->work);

        return 0;
}

static void drv2667_close(struct input_dev *input)
{
        struct drv2667_data *haptics = input_get_drvdata(input);
        int error;

        cancel_work_sync(&haptics->work);

        error = regmap_update_bits(haptics->regmap, DRV2667_CTRL_2,
                                   DRV2667_STANDBY, DRV2667_STANDBY);
        if (error)
                dev_err(&haptics->client->dev,
                        "Failed to enter standby mode: %d\n", error);
}

static const struct reg_sequence drv2667_init_regs[] = {
        { DRV2667_CTRL_2, 0 },
        { DRV2667_CTRL_1, DRV2667_25_VPP_GAIN },
        { DRV2667_WV_SEQ_0, 1 },
        { DRV2667_WV_SEQ_1, 0 }
};

static const struct reg_sequence drv2667_page1_init[] = {
        { DRV2667_RAM_HDR_SZ, 0x05 },
        { DRV2667_RAM_START_HI, 0x80 },
        { DRV2667_RAM_START_LO, 0x06 },
        { DRV2667_RAM_STOP_HI, 0x00 },
        { DRV2667_RAM_STOP_LO, 0x09 },
        { DRV2667_RAM_REPEAT_CT, 0 },
        { DRV2667_RAM_DURATION, 0x05 },
        { DRV2667_RAM_ENVELOPE, DRV2667_NO_ENV },
        { DRV2667_RAM_AMP, 0x60 },
};

static int drv2667_init(struct drv2667_data *haptics)
{
        int error;

        /* Set default haptic frequency to 195Hz on Page 1*/
        haptics->frequency = 195;
        haptics->page = DRV2667_PAGE_1;

        error = regmap_register_patch(haptics->regmap,
                                      drv2667_init_regs,
                                      ARRAY_SIZE(drv2667_init_regs));
        if (error) {
                dev_err(&haptics->client->dev,
                        "Failed to write init registers: %d\n",
                        error);
                return error;
        }

        error = regmap_write(haptics->regmap, DRV2667_PAGE, haptics->page);
        if (error) {
                dev_err(&haptics->client->dev, "Failed to set page: %d\n",
                        error);
                goto error_out;
        }

        error = drv2667_set_waveform_freq(haptics);
        if (error)
                goto error_page;

        error = regmap_register_patch(haptics->regmap,
                                      drv2667_page1_init,
                                      ARRAY_SIZE(drv2667_page1_init));
        if (error) {
                dev_err(&haptics->client->dev,
                        "Failed to write page registers: %d\n",
                        error);
                return error;
        }

        error = regmap_write(haptics->regmap, DRV2667_PAGE, DRV2667_PAGE_0);
        return error;

error_page:
        regmap_write(haptics->regmap, DRV2667_PAGE, DRV2667_PAGE_0);
error_out:
        return error;
}

static const struct regmap_config drv2667_regmap_config = {
        .reg_bits = 8,
        .val_bits = 8,

        .max_register = DRV2667_MAX_REG,
        .reg_defaults = drv2667_reg_defs,
        .num_reg_defaults = ARRAY_SIZE(drv2667_reg_defs),
        .cache_type = REGCACHE_NONE,
};

static int drv2667_probe(struct i2c_client *client)
{
        struct drv2667_data *haptics;
        int error;

        haptics = devm_kzalloc(&client->dev, sizeof(*haptics), GFP_KERNEL);
        if (!haptics)
                return -ENOMEM;

        haptics->regulator = devm_regulator_get(&client->dev, "vbat");
        if (IS_ERR(haptics->regulator)) {
                error = PTR_ERR(haptics->regulator);
                dev_err(&client->dev,
                        "unable to get regulator, error: %d\n", error);
                return error;
        }

        haptics->input_dev = devm_input_allocate_device(&client->dev);
        if (!haptics->input_dev) {
                dev_err(&client->dev, "Failed to allocate input device\n");
                return -ENOMEM;
        }

        haptics->input_dev->name = "drv2667:haptics";
        haptics->input_dev->dev.parent = client->dev.parent;
        haptics->input_dev->close = drv2667_close;
        input_set_drvdata(haptics->input_dev, haptics);
        input_set_capability(haptics->input_dev, EV_FF, FF_RUMBLE);

        error = input_ff_create_memless(haptics->input_dev, NULL,
                                        drv2667_haptics_play);
        if (error) {
                dev_err(&client->dev, "input_ff_create() failed: %d\n",
                        error);
                return error;
        }

        INIT_WORK(&haptics->work, drv2667_worker);

        haptics->client = client;
        i2c_set_clientdata(client, haptics);

        haptics->regmap = devm_regmap_init_i2c(client, &drv2667_regmap_config);
        if (IS_ERR(haptics->regmap)) {
                error = PTR_ERR(haptics->regmap);
                dev_err(&client->dev, "Failed to allocate register map: %d\n",
                        error);
                return error;
        }

        error = drv2667_init(haptics);
        if (error) {
                dev_err(&client->dev, "Device init failed: %d\n", error);
                return error;
        }

        error = input_register_device(haptics->input_dev);
        if (error) {
                dev_err(&client->dev, "couldn't register input device: %d\n",
                        error);
                return error;
        }

        return 0;
}

static int drv2667_suspend(struct device *dev)
{
        struct drv2667_data *haptics = dev_get_drvdata(dev);
        int error;

        guard(mutex)(&haptics->input_dev->mutex);

        if (input_device_enabled(haptics->input_dev)) {
                error = regmap_update_bits(haptics->regmap, DRV2667_CTRL_2,
                                           DRV2667_STANDBY, DRV2667_STANDBY);
                if (error) {
                        dev_err(dev, "Failed to set standby mode\n");
                        regulator_disable(haptics->regulator);
                        return error;
                }

                error = regulator_disable(haptics->regulator);
                if (error) {
                        dev_err(dev, "Failed to disable regulator\n");
                        regmap_update_bits(haptics->regmap,
                                           DRV2667_CTRL_2,
                                           DRV2667_STANDBY, 0);
                        return error;
                }
        }

        return 0;
}

static int drv2667_resume(struct device *dev)
{
        struct drv2667_data *haptics = dev_get_drvdata(dev);
        int error;

        guard(mutex)(&haptics->input_dev->mutex);

        if (input_device_enabled(haptics->input_dev)) {
                error = regulator_enable(haptics->regulator);
                if (error) {
                        dev_err(dev, "Failed to enable regulator\n");
                        return error;
                }

                error = regmap_update_bits(haptics->regmap, DRV2667_CTRL_2,
                                           DRV2667_STANDBY, 0);
                if (error) {
                        dev_err(dev, "Failed to unset standby mode\n");
                        regulator_disable(haptics->regulator);
                        return error;
                }

        }

        return 0;
}

static DEFINE_SIMPLE_DEV_PM_OPS(drv2667_pm_ops, drv2667_suspend, drv2667_resume);

static const struct i2c_device_id drv2667_id[] = {
        { "drv2667" },
        { }
};
MODULE_DEVICE_TABLE(i2c, drv2667_id);

#ifdef CONFIG_OF
static const struct of_device_id drv2667_of_match[] = {
        { .compatible = "ti,drv2667", },
        { }
};
MODULE_DEVICE_TABLE(of, drv2667_of_match);
#endif

static struct i2c_driver drv2667_driver = {
        .probe          = drv2667_probe,
        .driver         = {
                .name   = "drv2667-haptics",
                .of_match_table = of_match_ptr(drv2667_of_match),
                .pm     = pm_sleep_ptr(&drv2667_pm_ops),
        },
        .id_table = drv2667_id,
};
module_i2c_driver(drv2667_driver);

MODULE_DESCRIPTION("TI DRV2667 haptics driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");