// SPDX-License-Identifier: GPL-2.0+
/*
 * Driver for the ADC on Freescale Semiconductor MC13783 and MC13892 PMICs.
 *
 * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
 * Copyright (C) 2009 Sascha Hauer, Pengutronix
 */

#include <linux/mfd/mc13xxx.h>
#include <linux/platform_device.h>
#include <linux/hwmon-sysfs.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/hwmon.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/err.h>

#define DRIVER_NAME     "mc13783-adc"

/* platform device id driver data */
#define MC13783_ADC_16CHANS     1
#define MC13783_ADC_BPDIV2      2

struct mc13783_adc_priv {
        struct mc13xxx *mc13xxx;
        struct device *hwmon_dev;
        char name[PLATFORM_NAME_SIZE];
};

static ssize_t name_show(struct device *dev, struct device_attribute *devattr,
                         char *buf)
{
        struct mc13783_adc_priv *priv = dev_get_drvdata(dev);

        return sprintf(buf, "%s\n", priv->name);
}

static int mc13783_adc_read(struct device *dev,
                struct device_attribute *devattr, unsigned int *val)
{
        struct mc13783_adc_priv *priv = dev_get_drvdata(dev);
        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
        unsigned int channel = attr->index;
        unsigned int sample[4];
        int ret;

        ret = mc13xxx_adc_do_conversion(priv->mc13xxx,
                        MC13XXX_ADC_MODE_MULT_CHAN,
                        channel, 0, 0, sample);
        if (ret)
                return ret;

        /* ADIN7 subchannels */
        if (channel >= 16)
                channel = 7;

        channel &= 0x7;

        *val = (sample[channel % 4] >> (channel > 3 ? 14 : 2)) & 0x3ff;

        return 0;
}

static ssize_t mc13783_adc_bp_show(struct device *dev,
                                   struct device_attribute *devattr,
                                   char *buf)
{
        unsigned val;
        struct platform_device *pdev = to_platform_device(dev);
        kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data;
        int ret = mc13783_adc_read(dev, devattr, &val);

        if (ret)
                return ret;

        if (driver_data & MC13783_ADC_BPDIV2)
                val = DIV_ROUND_CLOSEST(val * 9, 2);
        else
                /*
                 * BP (channel 2) reports with offset 2.4V to the actual value
                 * to fit the input range of the ADC.  unit = 2.25mV = 9/4 mV.
                 */
                val = DIV_ROUND_CLOSEST(val * 9, 4) + 2400;

        return sprintf(buf, "%u\n", val);
}

static ssize_t mc13783_adc_gp_show(struct device *dev,
                                   struct device_attribute *devattr,
                                   char *buf)
{
        unsigned val;
        int ret = mc13783_adc_read(dev, devattr, &val);

        if (ret)
                return ret;

        /*
         * input range is [0, 2.3V], val has 10 bits, so each bit
         * is worth 9/4 mV.
         */
        val = DIV_ROUND_CLOSEST(val * 9, 4);

        return sprintf(buf, "%u\n", val);
}

static ssize_t mc13783_adc_uid_show(struct device *dev,
                                    struct device_attribute *devattr,
                                    char *buf)
{
        unsigned int val;
        struct platform_device *pdev = to_platform_device(dev);
        kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data;
        int ret = mc13783_adc_read(dev, devattr, &val);

        if (ret)
                return ret;

        if (driver_data & MC13783_ADC_BPDIV2)
                /* MC13892 have 1/2 divider, input range is [0, 4.800V] */
                val = DIV_ROUND_CLOSEST(val * 4800, 1024);
        else
                /* MC13783 have 0.9 divider, input range is [0, 2.555V] */
                val = DIV_ROUND_CLOSEST(val * 2555, 1024);

        return sprintf(buf, "%u\n", val);
}

static ssize_t mc13783_adc_temp_show(struct device *dev,
                                     struct device_attribute *devattr,
                                     char *buf)
{
        unsigned int val;
        struct platform_device *pdev = to_platform_device(dev);
        kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data;
        int ret = mc13783_adc_read(dev, devattr, &val);

        if (ret)
                return ret;

        if (driver_data & MC13783_ADC_BPDIV2) {
                /*
                 * MC13892:
                 * Die Temperature Read Out Code at 25C 680
                 * Temperature change per LSB +0.4244C
                 */
                ret = DIV_ROUND_CLOSEST(-2635920 + val * 4244, 10);
        } else {
                /*
                 * MC13783:
                 * Die Temperature Read Out Code at 25C 282
                 * Temperature change per LSB -1.14C
                 */
                ret = 346480 - 1140 * val;
        }

        return sprintf(buf, "%d\n", ret);
}

static DEVICE_ATTR_RO(name);
static SENSOR_DEVICE_ATTR_RO(in2_input, mc13783_adc_bp, 2);
static SENSOR_DEVICE_ATTR_RO(in5_input, mc13783_adc_gp, 5);
static SENSOR_DEVICE_ATTR_RO(in6_input, mc13783_adc_gp, 6);
static SENSOR_DEVICE_ATTR_RO(in7_input, mc13783_adc_gp, 7);
static SENSOR_DEVICE_ATTR_RO(in8_input, mc13783_adc_gp, 8);
static SENSOR_DEVICE_ATTR_RO(in9_input, mc13783_adc_gp, 9);
static SENSOR_DEVICE_ATTR_RO(in10_input, mc13783_adc_gp, 10);
static SENSOR_DEVICE_ATTR_RO(in11_input, mc13783_adc_gp, 11);
static SENSOR_DEVICE_ATTR_RO(in12_input, mc13783_adc_gp, 12);
static SENSOR_DEVICE_ATTR_RO(in13_input, mc13783_adc_gp, 13);
static SENSOR_DEVICE_ATTR_RO(in14_input, mc13783_adc_gp, 14);
static SENSOR_DEVICE_ATTR_RO(in15_input, mc13783_adc_gp, 15);
static SENSOR_DEVICE_ATTR_RO(in16_input, mc13783_adc_uid, 16);
static SENSOR_DEVICE_ATTR_RO(temp1_input, mc13783_adc_temp, 17);

static struct attribute *mc13783_attr_base[] = {
        &dev_attr_name.attr,
        &sensor_dev_attr_in2_input.dev_attr.attr,
        &sensor_dev_attr_in5_input.dev_attr.attr,
        &sensor_dev_attr_in6_input.dev_attr.attr,
        &sensor_dev_attr_in7_input.dev_attr.attr,
        &sensor_dev_attr_in16_input.dev_attr.attr,
        &sensor_dev_attr_temp1_input.dev_attr.attr,
        NULL
};

static const struct attribute_group mc13783_group_base = {
        .attrs = mc13783_attr_base,
};

/* these are only used if MC13783_ADC_16CHANS is provided in driver data */
static struct attribute *mc13783_attr_16chans[] = {
        &sensor_dev_attr_in8_input.dev_attr.attr,
        &sensor_dev_attr_in9_input.dev_attr.attr,
        &sensor_dev_attr_in10_input.dev_attr.attr,
        &sensor_dev_attr_in11_input.dev_attr.attr,
        NULL
};

static const struct attribute_group mc13783_group_16chans = {
        .attrs = mc13783_attr_16chans,
};

/* last four channels may be occupied by the touchscreen */
static struct attribute *mc13783_attr_ts[] = {
        &sensor_dev_attr_in12_input.dev_attr.attr,
        &sensor_dev_attr_in13_input.dev_attr.attr,
        &sensor_dev_attr_in14_input.dev_attr.attr,
        &sensor_dev_attr_in15_input.dev_attr.attr,
        NULL
};

static const struct attribute_group mc13783_group_ts = {
        .attrs = mc13783_attr_ts,
};

static int mc13783_adc_use_touchscreen(struct platform_device *pdev)
{
        struct mc13783_adc_priv *priv = platform_get_drvdata(pdev);
        unsigned flags = mc13xxx_get_flags(priv->mc13xxx);

        return flags & MC13XXX_USE_TOUCHSCREEN;
}

static int __init mc13783_adc_probe(struct platform_device *pdev)
{
        struct mc13783_adc_priv *priv;
        int ret;
        const struct platform_device_id *id = platform_get_device_id(pdev);
        char *dash;

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

        priv->mc13xxx = dev_get_drvdata(pdev->dev.parent);
        snprintf(priv->name, ARRAY_SIZE(priv->name), "%s", id->name);
        dash = strchr(priv->name, '-');
        if (dash)
                *dash = '\0';

        platform_set_drvdata(pdev, priv);

        /* Register sysfs hooks */
        ret = sysfs_create_group(&pdev->dev.kobj, &mc13783_group_base);
        if (ret)
                return ret;

        if (id->driver_data & MC13783_ADC_16CHANS) {
                ret = sysfs_create_group(&pdev->dev.kobj,
                                &mc13783_group_16chans);
                if (ret)
                        goto out_err_create_16chans;
        }

        if (!mc13783_adc_use_touchscreen(pdev)) {
                ret = sysfs_create_group(&pdev->dev.kobj, &mc13783_group_ts);
                if (ret)
                        goto out_err_create_ts;
        }

        priv->hwmon_dev = hwmon_device_register(&pdev->dev);
        if (IS_ERR(priv->hwmon_dev)) {
                ret = PTR_ERR(priv->hwmon_dev);
                dev_err(&pdev->dev,
                                "hwmon_device_register failed with %d.\n", ret);
                goto out_err_register;
        }

        return 0;

out_err_register:

        if (!mc13783_adc_use_touchscreen(pdev))
                sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_ts);
out_err_create_ts:

        if (id->driver_data & MC13783_ADC_16CHANS)
                sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_16chans);
out_err_create_16chans:

        sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_base);
        return ret;
}

static void mc13783_adc_remove(struct platform_device *pdev)
{
        struct mc13783_adc_priv *priv = platform_get_drvdata(pdev);
        kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data;

        hwmon_device_unregister(priv->hwmon_dev);

        if (!mc13783_adc_use_touchscreen(pdev))
                sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_ts);

        if (driver_data & MC13783_ADC_16CHANS)
                sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_16chans);

        sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_base);
}

static const struct platform_device_id mc13783_adc_idtable[] = {
        {
                .name = "mc13783-adc",
                .driver_data = MC13783_ADC_16CHANS,
        }, {
                .name = "mc13892-adc",
                .driver_data = MC13783_ADC_BPDIV2,
        }, {
                /* sentinel */
        }
};
MODULE_DEVICE_TABLE(platform, mc13783_adc_idtable);

static struct platform_driver mc13783_adc_driver = {
        .remove         = mc13783_adc_remove,
        .driver         = {
                .name   = DRIVER_NAME,
        },
        .id_table       = mc13783_adc_idtable,
};

module_platform_driver_probe(mc13783_adc_driver, mc13783_adc_probe);

MODULE_DESCRIPTION("MC13783 ADC driver");
MODULE_AUTHOR("Luotao Fu <l.fu@pengutronix.de>");
MODULE_LICENSE("GPL");