// SPDX-License-Identifier: GPL-2.0-only
/*
 * drivers/media/i2c/adp1653.c
 *
 * Copyright (C) 2008--2011 Nokia Corporation
 *
 * Contact: Sakari Ailus <sakari.ailus@iki.fi>
 *
 * Contributors:
 *      Sakari Ailus <sakari.ailus@iki.fi>
 *      Tuukka Toivonen <tuukkat76@gmail.com>
 *      Pavel Machek <pavel@ucw.cz>
 *
 * TODO:
 * - fault interrupt handling
 * - hardware strobe
 * - power doesn't need to be ON if all lights are off
 */

#include <linux/delay.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/gpio/consumer.h>
#include <media/i2c/adp1653.h>
#include <media/v4l2-device.h>

#define TIMEOUT_MAX             820000
#define TIMEOUT_STEP            54600
#define TIMEOUT_MIN             (TIMEOUT_MAX - ADP1653_REG_CONFIG_TMR_SET_MAX \
                                 * TIMEOUT_STEP)
#define TIMEOUT_US_TO_CODE(t)   ((TIMEOUT_MAX + (TIMEOUT_STEP / 2) - (t)) \
                                 / TIMEOUT_STEP)
#define TIMEOUT_CODE_TO_US(c)   (TIMEOUT_MAX - (c) * TIMEOUT_STEP)

/* Write values into ADP1653 registers. */
static int adp1653_update_hw(struct adp1653_flash *flash)
{
        struct i2c_client *client = v4l2_get_subdevdata(&flash->subdev);
        u8 out_sel;
        u8 config = 0;
        int rval;

        out_sel = ADP1653_INDICATOR_INTENSITY_uA_TO_REG(
                flash->indicator_intensity->val)
                << ADP1653_REG_OUT_SEL_ILED_SHIFT;

        switch (flash->led_mode->val) {
        case V4L2_FLASH_LED_MODE_NONE:
                break;
        case V4L2_FLASH_LED_MODE_FLASH:
                /* Flash mode, light on with strobe, duration from timer */
                config = ADP1653_REG_CONFIG_TMR_CFG;
                config |= TIMEOUT_US_TO_CODE(flash->flash_timeout->val)
                          << ADP1653_REG_CONFIG_TMR_SET_SHIFT;
                break;
        case V4L2_FLASH_LED_MODE_TORCH:
                /* Torch mode, light immediately on, duration indefinite */
                out_sel |= ADP1653_FLASH_INTENSITY_mA_TO_REG(
                        flash->torch_intensity->val)
                        << ADP1653_REG_OUT_SEL_HPLED_SHIFT;
                break;
        }

        rval = i2c_smbus_write_byte_data(client, ADP1653_REG_OUT_SEL, out_sel);
        if (rval < 0)
                return rval;

        rval = i2c_smbus_write_byte_data(client, ADP1653_REG_CONFIG, config);
        if (rval < 0)
                return rval;

        return 0;
}

static int adp1653_get_fault(struct adp1653_flash *flash)
{
        struct i2c_client *client = v4l2_get_subdevdata(&flash->subdev);
        int fault;
        int rval;

        fault = i2c_smbus_read_byte_data(client, ADP1653_REG_FAULT);
        if (fault < 0)
                return fault;

        flash->fault |= fault;

        if (!flash->fault)
                return 0;

        /* Clear faults. */
        rval = i2c_smbus_write_byte_data(client, ADP1653_REG_OUT_SEL, 0);
        if (rval < 0)
                return rval;

        flash->led_mode->val = V4L2_FLASH_LED_MODE_NONE;

        rval = adp1653_update_hw(flash);
        if (rval)
                return rval;

        return flash->fault;
}

static int adp1653_strobe(struct adp1653_flash *flash, int enable)
{
        struct i2c_client *client = v4l2_get_subdevdata(&flash->subdev);
        u8 out_sel = ADP1653_INDICATOR_INTENSITY_uA_TO_REG(
                flash->indicator_intensity->val)
                << ADP1653_REG_OUT_SEL_ILED_SHIFT;
        int rval;

        if (flash->led_mode->val != V4L2_FLASH_LED_MODE_FLASH)
                return -EBUSY;

        if (!enable)
                return i2c_smbus_write_byte_data(client, ADP1653_REG_OUT_SEL,
                                                 out_sel);

        out_sel |= ADP1653_FLASH_INTENSITY_mA_TO_REG(
                flash->flash_intensity->val)
                << ADP1653_REG_OUT_SEL_HPLED_SHIFT;
        rval = i2c_smbus_write_byte_data(client, ADP1653_REG_OUT_SEL, out_sel);
        if (rval)
                return rval;

        /* Software strobe using i2c */
        rval = i2c_smbus_write_byte_data(client, ADP1653_REG_SW_STROBE,
                ADP1653_REG_SW_STROBE_SW_STROBE);
        if (rval)
                return rval;
        return i2c_smbus_write_byte_data(client, ADP1653_REG_SW_STROBE, 0);
}

/* --------------------------------------------------------------------------
 * V4L2 controls
 */

static int adp1653_get_ctrl(struct v4l2_ctrl *ctrl)
{
        struct adp1653_flash *flash =
                container_of(ctrl->handler, struct adp1653_flash, ctrls);
        int rval;

        rval = adp1653_get_fault(flash);
        if (rval)
                return rval;

        ctrl->cur.val = 0;

        if (flash->fault & ADP1653_REG_FAULT_FLT_SCP)
                ctrl->cur.val |= V4L2_FLASH_FAULT_SHORT_CIRCUIT;
        if (flash->fault & ADP1653_REG_FAULT_FLT_OT)
                ctrl->cur.val |= V4L2_FLASH_FAULT_OVER_TEMPERATURE;
        if (flash->fault & ADP1653_REG_FAULT_FLT_TMR)
                ctrl->cur.val |= V4L2_FLASH_FAULT_TIMEOUT;
        if (flash->fault & ADP1653_REG_FAULT_FLT_OV)
                ctrl->cur.val |= V4L2_FLASH_FAULT_OVER_VOLTAGE;

        flash->fault = 0;

        return 0;
}

static int adp1653_set_ctrl(struct v4l2_ctrl *ctrl)
{
        struct adp1653_flash *flash =
                container_of(ctrl->handler, struct adp1653_flash, ctrls);
        int rval;

        rval = adp1653_get_fault(flash);
        if (rval)
                return rval;
        if ((rval & (ADP1653_REG_FAULT_FLT_SCP |
                     ADP1653_REG_FAULT_FLT_OT |
                     ADP1653_REG_FAULT_FLT_OV)) &&
            (ctrl->id == V4L2_CID_FLASH_STROBE ||
             ctrl->id == V4L2_CID_FLASH_TORCH_INTENSITY ||
             ctrl->id == V4L2_CID_FLASH_LED_MODE))
                return -EBUSY;

        switch (ctrl->id) {
        case V4L2_CID_FLASH_STROBE:
                return adp1653_strobe(flash, 1);
        case V4L2_CID_FLASH_STROBE_STOP:
                return adp1653_strobe(flash, 0);
        }

        return adp1653_update_hw(flash);
}

static const struct v4l2_ctrl_ops adp1653_ctrl_ops = {
        .g_volatile_ctrl = adp1653_get_ctrl,
        .s_ctrl = adp1653_set_ctrl,
};

static int adp1653_init_controls(struct adp1653_flash *flash)
{
        struct v4l2_ctrl *fault;

        v4l2_ctrl_handler_init(&flash->ctrls, 9);

        flash->led_mode =
                v4l2_ctrl_new_std_menu(&flash->ctrls, &adp1653_ctrl_ops,
                                       V4L2_CID_FLASH_LED_MODE,
                                       V4L2_FLASH_LED_MODE_TORCH, ~0x7, 0);
        v4l2_ctrl_new_std_menu(&flash->ctrls, &adp1653_ctrl_ops,
                               V4L2_CID_FLASH_STROBE_SOURCE,
                               V4L2_FLASH_STROBE_SOURCE_SOFTWARE, ~0x1, 0);
        v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
                          V4L2_CID_FLASH_STROBE, 0, 0, 0, 0);
        v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
                          V4L2_CID_FLASH_STROBE_STOP, 0, 0, 0, 0);
        flash->flash_timeout =
                v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
                                  V4L2_CID_FLASH_TIMEOUT, TIMEOUT_MIN,
                                  flash->platform_data->max_flash_timeout,
                                  TIMEOUT_STEP,
                                  flash->platform_data->max_flash_timeout);
        flash->flash_intensity =
                v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
                                  V4L2_CID_FLASH_INTENSITY,
                                  ADP1653_FLASH_INTENSITY_MIN,
                                  flash->platform_data->max_flash_intensity,
                                  1, flash->platform_data->max_flash_intensity);
        flash->torch_intensity =
                v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
                                  V4L2_CID_FLASH_TORCH_INTENSITY,
                                  ADP1653_TORCH_INTENSITY_MIN,
                                  flash->platform_data->max_torch_intensity,
                                  ADP1653_FLASH_INTENSITY_STEP,
                                  flash->platform_data->max_torch_intensity);
        flash->indicator_intensity =
                v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
                                  V4L2_CID_FLASH_INDICATOR_INTENSITY,
                                  ADP1653_INDICATOR_INTENSITY_MIN,
                                  flash->platform_data->max_indicator_intensity,
                                  ADP1653_INDICATOR_INTENSITY_STEP,
                                  ADP1653_INDICATOR_INTENSITY_MIN);
        fault = v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
                                  V4L2_CID_FLASH_FAULT, 0,
                                  V4L2_FLASH_FAULT_OVER_VOLTAGE
                                  | V4L2_FLASH_FAULT_OVER_TEMPERATURE
                                  | V4L2_FLASH_FAULT_SHORT_CIRCUIT, 0, 0);

        if (flash->ctrls.error)
                return flash->ctrls.error;

        fault->flags |= V4L2_CTRL_FLAG_VOLATILE;

        flash->subdev.ctrl_handler = &flash->ctrls;
        return 0;
}

/* --------------------------------------------------------------------------
 * V4L2 subdev operations
 */

static int
adp1653_init_device(struct adp1653_flash *flash)
{
        struct i2c_client *client = v4l2_get_subdevdata(&flash->subdev);
        int rval;

        /* Clear FAULT register by writing zero to OUT_SEL */
        rval = i2c_smbus_write_byte_data(client, ADP1653_REG_OUT_SEL, 0);
        if (rval < 0) {
                dev_err(&client->dev, "failed writing fault register\n");
                return -EIO;
        }

        mutex_lock(flash->ctrls.lock);
        /* Reset faults before reading new ones. */
        flash->fault = 0;
        rval = adp1653_get_fault(flash);
        mutex_unlock(flash->ctrls.lock);
        if (rval > 0) {
                dev_err(&client->dev, "faults detected: 0x%1.1x\n", rval);
                return -EIO;
        }

        mutex_lock(flash->ctrls.lock);
        rval = adp1653_update_hw(flash);
        mutex_unlock(flash->ctrls.lock);
        if (rval) {
                dev_err(&client->dev,
                        "adp1653_update_hw failed at %s\n", __func__);
                return -EIO;
        }

        return 0;
}

static int
__adp1653_set_power(struct adp1653_flash *flash, int on)
{
        int ret;

        if (flash->platform_data->power) {
                ret = flash->platform_data->power(&flash->subdev, on);
                if (ret < 0)
                        return ret;
        } else {
                gpiod_set_value(flash->platform_data->enable_gpio, on);
                if (on)
                        /* Some delay is apparently required. */
                        udelay(20);
        }

        if (!on)
                return 0;

        ret = adp1653_init_device(flash);
        if (ret >= 0)
                return ret;

        if (flash->platform_data->power)
                flash->platform_data->power(&flash->subdev, 0);
        else
                gpiod_set_value(flash->platform_data->enable_gpio, 0);

        return ret;
}

static int
adp1653_set_power(struct v4l2_subdev *subdev, int on)
{
        struct adp1653_flash *flash = to_adp1653_flash(subdev);
        int ret = 0;

        mutex_lock(&flash->power_lock);

        /* If the power count is modified from 0 to != 0 or from != 0 to 0,
         * update the power state.
         */
        if (flash->power_count == !on) {
                ret = __adp1653_set_power(flash, !!on);
                if (ret < 0)
                        goto done;
        }

        /* Update the power count. */
        flash->power_count += on ? 1 : -1;
        WARN_ON(flash->power_count < 0);

done:
        mutex_unlock(&flash->power_lock);
        return ret;
}

static int adp1653_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
{
        return adp1653_set_power(sd, 1);
}

static int adp1653_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
{
        return adp1653_set_power(sd, 0);
}

static const struct v4l2_subdev_core_ops adp1653_core_ops = {
        .s_power = adp1653_set_power,
};

static const struct v4l2_subdev_ops adp1653_ops = {
        .core = &adp1653_core_ops,
};

static const struct v4l2_subdev_internal_ops adp1653_internal_ops = {
        .open = adp1653_open,
        .close = adp1653_close,
};

/* --------------------------------------------------------------------------
 * I2C driver
 */
#ifdef CONFIG_PM

static int adp1653_suspend(struct device *dev)
{
        struct v4l2_subdev *subdev = dev_get_drvdata(dev);
        struct adp1653_flash *flash = to_adp1653_flash(subdev);

        if (!flash->power_count)
                return 0;

        return __adp1653_set_power(flash, 0);
}

static int adp1653_resume(struct device *dev)
{
        struct v4l2_subdev *subdev = dev_get_drvdata(dev);
        struct adp1653_flash *flash = to_adp1653_flash(subdev);

        if (!flash->power_count)
                return 0;

        return __adp1653_set_power(flash, 1);
}

#else

#define adp1653_suspend NULL
#define adp1653_resume  NULL

#endif /* CONFIG_PM */

static int adp1653_of_init(struct i2c_client *client,
                           struct adp1653_flash *flash,
                           struct device_node *node)
{
        struct adp1653_platform_data *pd;
        struct device_node *node_indicator = NULL;
        struct device_node *node_flash;

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

        node_flash = of_get_child_by_name(node, "flash");
        if (!node_flash)
                return -EINVAL;

        if (of_property_read_u32(node_flash, "flash-timeout-us",
                                 &pd->max_flash_timeout))
                goto err;

        if (of_property_read_u32(node_flash, "flash-max-microamp",
                                 &pd->max_flash_intensity))
                goto err;

        pd->max_flash_intensity /= 1000;

        if (of_property_read_u32(node_flash, "led-max-microamp",
                                 &pd->max_torch_intensity))
                goto err;

        pd->max_torch_intensity /= 1000;

        node_indicator = of_get_child_by_name(node, "indicator");
        if (!node_indicator)
                goto err;

        if (of_property_read_u32(node_indicator, "led-max-microamp",
                                 &pd->max_indicator_intensity))
                goto err;

        of_node_put(node_flash);
        of_node_put(node_indicator);

        pd->enable_gpio = devm_gpiod_get(&client->dev, "enable", GPIOD_OUT_LOW);
        if (IS_ERR(pd->enable_gpio)) {
                dev_err(&client->dev, "Error getting GPIO\n");
                return PTR_ERR(pd->enable_gpio);
        }

        return 0;
err:
        dev_err(&client->dev, "Required property not found\n");
        of_node_put(node_flash);
        of_node_put(node_indicator);
        return -EINVAL;
}


static int adp1653_probe(struct i2c_client *client)
{
        struct adp1653_flash *flash;
        int ret;

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

        if (client->dev.of_node) {
                ret = adp1653_of_init(client, flash, client->dev.of_node);
                if (ret)
                        return ret;
        } else {
                if (!client->dev.platform_data) {
                        dev_err(&client->dev,
                                "Neither DT not platform data provided\n");
                        return -EINVAL;
                }
                flash->platform_data = client->dev.platform_data;
        }

        mutex_init(&flash->power_lock);

        v4l2_i2c_subdev_init(&flash->subdev, client, &adp1653_ops);
        flash->subdev.internal_ops = &adp1653_internal_ops;
        flash->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;

        ret = adp1653_init_controls(flash);
        if (ret)
                goto free_and_quit;

        ret = media_entity_pads_init(&flash->subdev.entity, 0, NULL);
        if (ret < 0)
                goto free_and_quit;

        flash->subdev.entity.function = MEDIA_ENT_F_FLASH;

        return 0;

free_and_quit:
        dev_err(&client->dev, "adp1653: failed to register device\n");
        v4l2_ctrl_handler_free(&flash->ctrls);
        return ret;
}

static void adp1653_remove(struct i2c_client *client)
{
        struct v4l2_subdev *subdev = i2c_get_clientdata(client);
        struct adp1653_flash *flash = to_adp1653_flash(subdev);

        v4l2_device_unregister_subdev(&flash->subdev);
        v4l2_ctrl_handler_free(&flash->ctrls);
        media_entity_cleanup(&flash->subdev.entity);
}

static const struct i2c_device_id adp1653_id_table[] = {
        { ADP1653_NAME },
        { }
};
MODULE_DEVICE_TABLE(i2c, adp1653_id_table);

static const struct dev_pm_ops adp1653_pm_ops = {
        .suspend        = adp1653_suspend,
        .resume         = adp1653_resume,
};

static struct i2c_driver adp1653_i2c_driver = {
        .driver         = {
                .name   = ADP1653_NAME,
                .pm     = &adp1653_pm_ops,
        },
        .probe          = adp1653_probe,
        .remove         = adp1653_remove,
        .id_table       = adp1653_id_table,
};

module_i2c_driver(adp1653_i2c_driver);

MODULE_AUTHOR("Sakari Ailus <sakari.ailus@nokia.com>");
MODULE_DESCRIPTION("Analog Devices ADP1653 LED flash driver");
MODULE_LICENSE("GPL");