// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2012 Intel Corporation

/*
 * Based on linux/modules/camera/drivers/media/i2c/imx/dw9719.c from:
 * https://github.com/ZenfoneArea/android_kernel_asus_zenfone5 and
 * latte-l-oss/drivers/external_drivers/camera/drivers/media/i2c/micam/dw9761.c
 * from: https://github.com/MiCode/Xiaomi_Kernel_OpenSource/
 */

#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/pm_runtime.h>
#include <linux/regulator/consumer.h>
#include <linux/types.h>

#include <media/v4l2-cci.h>
#include <media/v4l2-common.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-subdev.h>

#define DW9719_MAX_FOCUS_POS    1023
#define DW9719_CTRL_STEPS       16
#define DW9719_CTRL_DELAY_US    1000

#define DW9718S_PD                      CCI_REG8(0)

#define DW9718S_CONTROL                 CCI_REG8(1)
#define DW9718S_CONTROL_SW_LINEAR       BIT(0)
#define DW9718S_CONTROL_SAC_SHIFT       1
#define DW9718S_CONTROL_SAC_MASK        0x7
#define DW9718S_CONTROL_OCP_DISABLE     BIT(4)
#define DW9718S_CONTROL_UVLO_DISABLE    BIT(5)
#define DW9718S_DEFAULT_SAC             4

#define DW9718S_VCM_CURRENT             CCI_REG16(2)

#define DW9718S_SW                      CCI_REG8(4)
#define DW9718S_SW_VCM_FREQ_MASK        0xF
#define DW9718S_DEFAULT_VCM_FREQ        0

#define DW9718S_SACT                    CCI_REG8(5)
#define DW9718S_SACT_PERIOD_8_8MS       0x19

#define DW9719_INFO                     CCI_REG8(0)
#define DW9719_ID                       0xF1
#define DW9761_ID                       0xF4

#define DW9719_CONTROL                  CCI_REG8(2)
#define DW9719_STANDBY                  0x00
#define DW9719_SHUTDOWN                 0x01
#define DW9719_ENABLE_RINGING           0x02

#define DW9719_VCM_CURRENT              CCI_REG16(3)

#define DW9719_STATUS                   CCI_REG16(5)
#define DW9719_STATUS_BUSY              BIT(0)

#define DW9719_MODE                     CCI_REG8(6)
#define DW9719_MODE_SAC_SHIFT           4
#define DW9719_DEFAULT_SAC              4
#define DW9761_DEFAULT_SAC              6

#define DW9719_VCM_FREQ                 CCI_REG8(7)
#define DW9719_DEFAULT_VCM_FREQ         0x60
#define DW9761_DEFAULT_VCM_FREQ         0x3E

#define DW9761_VCM_PRELOAD              CCI_REG8(8)
#define DW9761_DEFAULT_VCM_PRELOAD      0x73

#define DW9800K_DEFAULT_SAC             1
#define DW9800K_MODE_SAC_SHIFT          6
#define DW9800K_DEFAULT_VCM_FREQ                0x10

#define to_dw9719_device(x) container_of(x, struct dw9719_device, sd)

enum dw9719_model {
        DW9718S,
        DW9719,
        DW9761,
        DW9800K,
};

struct dw9719_device {
        struct v4l2_subdev sd;
        struct device *dev;
        struct regmap *regmap;
        struct regulator *regulator;
        enum dw9719_model model;
        u32 mode_low_bits;
        u32 sac_mode;
        u32 vcm_freq;

        struct dw9719_v4l2_ctrls {
                struct v4l2_ctrl_handler handler;
                struct v4l2_ctrl *focus;
        } ctrls;
};

static int dw9719_power_down(struct dw9719_device *dw9719)
{
        u32 reg_pwr = dw9719->model == DW9718S ? DW9718S_PD : DW9719_CONTROL;

        /*
         * Worth engaging the internal SHUTDOWN mode especially due to the
         * regulator being potentially shared with other devices.
         */
        if (cci_write(dw9719->regmap, reg_pwr, DW9719_SHUTDOWN, NULL))
                dev_err(dw9719->dev, "Error writing to power register\n");
        return regulator_disable(dw9719->regulator);
}

static int dw9719_power_up(struct dw9719_device *dw9719, bool detect)
{
        u32 reg_pwr = dw9719->model == DW9718S ? DW9718S_PD : DW9719_CONTROL;
        u64 val;
        int ret;
        int err;

        ret = regulator_enable(dw9719->regulator);
        if (ret)
                return ret;

        /*
         * Need 100us to transition from SHUTDOWN to STANDBY.
         * Jiggle the SCL pin to wake up the device (even when the regulator is
         * shared) and wait double the time to be sure, as 100us is not enough
         * at least on the DW9718S as found on the motorola-nora smartphone,
         * then retry the write.
         */
        cci_write(dw9719->regmap, reg_pwr, DW9719_STANDBY, NULL);
        /* the jiggle is expected to fail, don't even log that as error */
        fsleep(200);
        cci_write(dw9719->regmap, reg_pwr, DW9719_STANDBY, &ret);

        if (detect) {
                /* These models do not have an INFO register */
                switch (dw9719->model) {
                case DW9718S:
                        dw9719->sac_mode = DW9718S_DEFAULT_SAC;
                        dw9719->vcm_freq = DW9718S_DEFAULT_VCM_FREQ;
                        goto props;
                case DW9800K:
                        dw9719->sac_mode = DW9800K_DEFAULT_SAC;
                        dw9719->vcm_freq = DW9800K_DEFAULT_VCM_FREQ;
                        goto props;
                default:
                        break;
                }

                ret = cci_read(dw9719->regmap, DW9719_INFO, &val, NULL);
                if (ret < 0)
                        return ret;

                switch (val) {
                case DW9719_ID:
                        dw9719->model = DW9719;
                        dw9719->mode_low_bits = 0x00;
                        dw9719->sac_mode = DW9719_DEFAULT_SAC;
                        dw9719->vcm_freq = DW9719_DEFAULT_VCM_FREQ;
                        break;
                case DW9761_ID:
                        dw9719->model = DW9761;
                        dw9719->mode_low_bits = 0x01;
                        dw9719->sac_mode = DW9761_DEFAULT_SAC;
                        dw9719->vcm_freq = DW9761_DEFAULT_VCM_FREQ;
                        break;
                default:
                        dev_err(dw9719->dev,
                                "Error unknown device id 0x%02llx\n", val);
                        return -ENXIO;
                }

props:
                /* Optional indication of SAC mode select */
                device_property_read_u32(dw9719->dev, "dongwoon,sac-mode",
                                         &dw9719->sac_mode);

                /* Optional indication of VCM frequency */
                err = device_property_read_u32(dw9719->dev, "dongwoon,vcm-freq",
                                               &dw9719->vcm_freq);
                if (err == 0)
                        dev_warn(dw9719->dev, "dongwoon,vcm-freq property is deprecated, please use dongwoon,vcm-prescale\n");

                /* Optional indication of VCM prescale */
                device_property_read_u32(dw9719->dev, "dongwoon,vcm-prescale",
                                         &dw9719->vcm_freq);
        }

        switch (dw9719->model) {
        case DW9800K:
                cci_write(dw9719->regmap, DW9719_CONTROL, DW9719_ENABLE_RINGING, &ret);
                cci_write(dw9719->regmap, DW9719_MODE,
                          dw9719->sac_mode << DW9800K_MODE_SAC_SHIFT, &ret);
                cci_write(dw9719->regmap, DW9719_VCM_FREQ, dw9719->vcm_freq, &ret);
                break;
        case DW9718S:
                /* Datasheet says [OCP/UVLO] should be disabled below 2.5V */
                dw9719->sac_mode &= DW9718S_CONTROL_SAC_MASK;
                cci_write(dw9719->regmap, DW9718S_CONTROL,
                          DW9718S_CONTROL_SW_LINEAR |
                          (dw9719->sac_mode << DW9718S_CONTROL_SAC_SHIFT) |
                          DW9718S_CONTROL_OCP_DISABLE |
                          DW9718S_CONTROL_UVLO_DISABLE, &ret);
                cci_write(dw9719->regmap, DW9718S_SACT,
                          DW9718S_SACT_PERIOD_8_8MS, &ret);
                cci_write(dw9719->regmap, DW9718S_SW,
                          dw9719->vcm_freq & DW9718S_SW_VCM_FREQ_MASK, &ret);
                break;
        case DW9761:
                cci_write(dw9719->regmap, DW9761_VCM_PRELOAD,
                          DW9761_DEFAULT_VCM_PRELOAD, &ret);
                fallthrough;
        case DW9719:
                cci_write(dw9719->regmap, DW9719_CONTROL, DW9719_ENABLE_RINGING, &ret);
                cci_write(dw9719->regmap, DW9719_MODE, dw9719->mode_low_bits |
                                  (dw9719->sac_mode << DW9719_MODE_SAC_SHIFT), &ret);
                cci_write(dw9719->regmap, DW9719_VCM_FREQ, dw9719->vcm_freq, &ret);
        }

        if (ret)
                dw9719_power_down(dw9719);

        return ret;
}

static int dw9719_t_focus_abs(struct dw9719_device *dw9719, s32 value)
{
        u32 reg = dw9719->model == DW9718S ? DW9718S_VCM_CURRENT
                                           : DW9719_VCM_CURRENT;
        return cci_write(dw9719->regmap, reg, value, NULL);
}

static int dw9719_set_ctrl(struct v4l2_ctrl *ctrl)
{
        struct dw9719_device *dw9719 = container_of(ctrl->handler,
                                                    struct dw9719_device,
                                                    ctrls.handler);
        int ret;

        /* Only apply changes to the controls if the device is powered up */
        if (!pm_runtime_get_if_in_use(dw9719->dev))
                return 0;

        switch (ctrl->id) {
        case V4L2_CID_FOCUS_ABSOLUTE:
                ret = dw9719_t_focus_abs(dw9719, ctrl->val);
                break;
        default:
                ret = -EINVAL;
        }

        pm_runtime_put(dw9719->dev);

        return ret;
}

static const struct v4l2_ctrl_ops dw9719_ctrl_ops = {
        .s_ctrl = dw9719_set_ctrl,
};

static int dw9719_suspend(struct device *dev)
{
        struct v4l2_subdev *sd = dev_get_drvdata(dev);
        struct dw9719_device *dw9719 = to_dw9719_device(sd);
        int ret;
        int val;

        for (val = dw9719->ctrls.focus->val; val >= 0;
             val -= DW9719_CTRL_STEPS) {
                ret = dw9719_t_focus_abs(dw9719, val);
                if (ret)
                        return ret;

                usleep_range(DW9719_CTRL_DELAY_US, DW9719_CTRL_DELAY_US + 10);
        }

        return dw9719_power_down(dw9719);
}

static int dw9719_resume(struct device *dev)
{
        struct v4l2_subdev *sd = dev_get_drvdata(dev);
        struct dw9719_device *dw9719 = to_dw9719_device(sd);
        int current_focus = dw9719->ctrls.focus->val;
        int ret;
        int val;

        ret = dw9719_power_up(dw9719, false);
        if (ret)
                return ret;

        for (val = current_focus % DW9719_CTRL_STEPS; val < current_focus;
             val += DW9719_CTRL_STEPS) {
                ret = dw9719_t_focus_abs(dw9719, val);
                if (ret)
                        goto err_power_down;

                usleep_range(DW9719_CTRL_DELAY_US, DW9719_CTRL_DELAY_US + 10);
        }

        return 0;

err_power_down:
        dw9719_power_down(dw9719);
        return ret;
}

static int dw9719_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
{
        return pm_runtime_resume_and_get(sd->dev);
}

static int dw9719_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
{
        pm_runtime_put_autosuspend(sd->dev);

        return 0;
}

static const struct v4l2_subdev_internal_ops dw9719_internal_ops = {
        .open = dw9719_open,
        .close = dw9719_close,
};

static int dw9719_init_controls(struct dw9719_device *dw9719)
{
        const struct v4l2_ctrl_ops *ops = &dw9719_ctrl_ops;
        int ret;

        v4l2_ctrl_handler_init(&dw9719->ctrls.handler, 1);

        dw9719->ctrls.focus = v4l2_ctrl_new_std(&dw9719->ctrls.handler, ops,
                                                V4L2_CID_FOCUS_ABSOLUTE, 0,
                                                DW9719_MAX_FOCUS_POS, 1, 0);

        if (dw9719->ctrls.handler.error) {
                dev_err(dw9719->dev, "Error initialising v4l2 ctrls\n");
                ret = dw9719->ctrls.handler.error;
                goto err_free_handler;
        }

        dw9719->sd.ctrl_handler = &dw9719->ctrls.handler;
        return 0;

err_free_handler:
        v4l2_ctrl_handler_free(&dw9719->ctrls.handler);
        return ret;
}

static const struct v4l2_subdev_ops dw9719_ops = { };

static int dw9719_probe(struct i2c_client *client)
{
        struct dw9719_device *dw9719;
        int ret;

        dw9719 = devm_kzalloc(&client->dev, sizeof(*dw9719), GFP_KERNEL);
        if (!dw9719)
                return -ENOMEM;

        dw9719->model = (enum dw9719_model)(uintptr_t)i2c_get_match_data(client);

        dw9719->regmap = devm_cci_regmap_init_i2c(client, 8);
        if (IS_ERR(dw9719->regmap))
                return PTR_ERR(dw9719->regmap);

        dw9719->dev = &client->dev;

        dw9719->regulator = devm_regulator_get(&client->dev, "vdd");
        if (IS_ERR(dw9719->regulator))
                return dev_err_probe(&client->dev, PTR_ERR(dw9719->regulator),
                                     "getting regulator\n");

        v4l2_i2c_subdev_init(&dw9719->sd, client, &dw9719_ops);
        dw9719->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
        dw9719->sd.internal_ops = &dw9719_internal_ops;

        ret = dw9719_init_controls(dw9719);
        if (ret)
                return ret;

        ret = media_entity_pads_init(&dw9719->sd.entity, 0, NULL);
        if (ret < 0)
                goto err_free_ctrl_handler;

        dw9719->sd.entity.function = MEDIA_ENT_F_LENS;

        /*
         * We need the driver to work in the event that pm runtime is disable in
         * the kernel, so power up and verify the chip now. In the event that
         * runtime pm is disabled this will leave the chip on, so that the lens
         * will work.
         */

        ret = dw9719_power_up(dw9719, true);
        if (ret)
                goto err_cleanup_media;

        pm_runtime_set_active(&client->dev);
        pm_runtime_get_noresume(&client->dev);
        pm_runtime_enable(&client->dev);

        ret = v4l2_async_register_subdev(&dw9719->sd);
        if (ret < 0)
                goto err_pm_runtime;

        pm_runtime_set_autosuspend_delay(&client->dev, 1000);
        pm_runtime_use_autosuspend(&client->dev);
        pm_runtime_put_autosuspend(&client->dev);

        return ret;

err_pm_runtime:
        pm_runtime_disable(&client->dev);
        pm_runtime_put_noidle(&client->dev);
        dw9719_power_down(dw9719);
err_cleanup_media:
        media_entity_cleanup(&dw9719->sd.entity);
err_free_ctrl_handler:
        v4l2_ctrl_handler_free(&dw9719->ctrls.handler);

        return ret;
}

static void dw9719_remove(struct i2c_client *client)
{
        struct v4l2_subdev *sd = i2c_get_clientdata(client);
        struct dw9719_device *dw9719 =
                container_of(sd, struct dw9719_device, sd);

        v4l2_async_unregister_subdev(sd);
        v4l2_ctrl_handler_free(&dw9719->ctrls.handler);
        media_entity_cleanup(&dw9719->sd.entity);

        pm_runtime_disable(&client->dev);
        if (!pm_runtime_status_suspended(&client->dev))
                dw9719_power_down(dw9719);
        pm_runtime_set_suspended(&client->dev);
}

static const struct i2c_device_id dw9719_id_table[] = {
        { .name = "dw9718s", .driver_data = (kernel_ulong_t)DW9718S },
        { .name = "dw9719", .driver_data = (kernel_ulong_t)DW9719 },
        { .name = "dw9761", .driver_data = (kernel_ulong_t)DW9761 },
        { .name = "dw9800k", .driver_data = (kernel_ulong_t)DW9800K },
        { }
};
MODULE_DEVICE_TABLE(i2c, dw9719_id_table);

static const struct of_device_id dw9719_of_table[] = {
        { .compatible = "dongwoon,dw9718s", .data = (const void *)DW9718S },
        { .compatible = "dongwoon,dw9719", .data = (const void *)DW9719 },
        { .compatible = "dongwoon,dw9761", .data = (const void *)DW9761 },
        { .compatible = "dongwoon,dw9800k", .data = (const void *)DW9800K },
        { }
};
MODULE_DEVICE_TABLE(of, dw9719_of_table);

static DEFINE_RUNTIME_DEV_PM_OPS(dw9719_pm_ops, dw9719_suspend, dw9719_resume,
                                 NULL);

static struct i2c_driver dw9719_i2c_driver = {
        .driver = {
                .name = "dw9719",
                .pm = pm_sleep_ptr(&dw9719_pm_ops),
                .of_match_table = dw9719_of_table,
        },
        .probe = dw9719_probe,
        .remove = dw9719_remove,
        .id_table = dw9719_id_table,
};
module_i2c_driver(dw9719_i2c_driver);

MODULE_AUTHOR("Daniel Scally <djrscally@gmail.com>");
MODULE_DESCRIPTION("DW9719 VCM Driver");
MODULE_LICENSE("GPL");