/*
 * Copyright (c) 2011-2016 Synaptics Incorporated
 * Copyright (c) 2011 Unixphere
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 */

#include <linux/kernel.h>
#include <linux/kconfig.h>
#include <linux/rmi.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/of.h>
#include <asm/unaligned.h>
#include "rmi_driver.h"

#define RMI_PRODUCT_ID_LENGTH    10
#define RMI_PRODUCT_INFO_LENGTH   2

#define RMI_DATE_CODE_LENGTH      3

#define PRODUCT_ID_OFFSET 0x10
#define PRODUCT_INFO_OFFSET 0x1E


/* Force a firmware reset of the sensor */
#define RMI_F01_CMD_DEVICE_RESET        1

/* Various F01_RMI_QueryX bits */

#define RMI_F01_QRY1_CUSTOM_MAP         BIT(0)
#define RMI_F01_QRY1_NON_COMPLIANT      BIT(1)
#define RMI_F01_QRY1_HAS_LTS            BIT(2)
#define RMI_F01_QRY1_HAS_SENSOR_ID      BIT(3)
#define RMI_F01_QRY1_HAS_CHARGER_INP    BIT(4)
#define RMI_F01_QRY1_HAS_ADJ_DOZE       BIT(5)
#define RMI_F01_QRY1_HAS_ADJ_DOZE_HOFF  BIT(6)
#define RMI_F01_QRY1_HAS_QUERY42        BIT(7)

#define RMI_F01_QRY5_YEAR_MASK          0x1f
#define RMI_F01_QRY6_MONTH_MASK         0x0f
#define RMI_F01_QRY7_DAY_MASK           0x1f

#define RMI_F01_QRY2_PRODINFO_MASK      0x7f

#define RMI_F01_BASIC_QUERY_LEN         21 /* From Query 00 through 20 */

struct f01_basic_properties {
        u8 manufacturer_id;
        bool has_lts;
        bool has_adjustable_doze;
        bool has_adjustable_doze_holdoff;
        char dom[11]; /* YYYY/MM/DD + '\0' */
        u8 product_id[RMI_PRODUCT_ID_LENGTH + 1];
        u16 productinfo;
        u32 firmware_id;
        u32 package_id;
};

/* F01 device status bits */

/* Most recent device status event */
#define RMI_F01_STATUS_CODE(status)             ((status) & 0x0f)
/* The device has lost its configuration for some reason. */
#define RMI_F01_STATUS_UNCONFIGURED(status)     (!!((status) & 0x80))

/* Control register bits */

/*
 * Sleep mode controls power management on the device and affects all
 * functions of the device.
 */
#define RMI_F01_CTRL0_SLEEP_MODE_MASK   0x03

#define RMI_SLEEP_MODE_NORMAL           0x00
#define RMI_SLEEP_MODE_SENSOR_SLEEP     0x01
#define RMI_SLEEP_MODE_RESERVED0        0x02
#define RMI_SLEEP_MODE_RESERVED1        0x03

/*
 * This bit disables whatever sleep mode may be selected by the sleep_mode
 * field and forces the device to run at full power without sleeping.
 */
#define RMI_F01_CTRL0_NOSLEEP_BIT       BIT(2)

/*
 * When this bit is set, the touch controller employs a noise-filtering
 * algorithm designed for use with a connected battery charger.
 */
#define RMI_F01_CTRL0_CHARGER_BIT       BIT(5)

/*
 * Sets the report rate for the device. The effect of this setting is
 * highly product dependent. Check the spec sheet for your particular
 * touch sensor.
 */
#define RMI_F01_CTRL0_REPORTRATE_BIT    BIT(6)

/*
 * Written by the host as an indicator that the device has been
 * successfully configured.
 */
#define RMI_F01_CTRL0_CONFIGURED_BIT    BIT(7)

/**
 * @ctrl0 - see the bit definitions above.
 * @doze_interval - controls the interval between checks for finger presence
 * when the touch sensor is in doze mode, in units of 10ms.
 * @wakeup_threshold - controls the capacitance threshold at which the touch
 * sensor will decide to wake up from that low power state.
 * @doze_holdoff - controls how long the touch sensor waits after the last
 * finger lifts before entering the doze state, in units of 100ms.
 */
struct f01_device_control {
        u8 ctrl0;
        u8 doze_interval;
        u8 wakeup_threshold;
        u8 doze_holdoff;
};

struct f01_data {
        struct f01_basic_properties properties;
        struct f01_device_control device_control;

        u16 doze_interval_addr;
        u16 wakeup_threshold_addr;
        u16 doze_holdoff_addr;

        bool suspended;
        bool old_nosleep;

        unsigned int num_of_irq_regs;
};

static int rmi_f01_read_properties(struct rmi_device *rmi_dev,
                                   u16 query_base_addr,
                                   struct f01_basic_properties *props)
{
        u8 queries[RMI_F01_BASIC_QUERY_LEN];
        int ret;
        int query_offset = query_base_addr;
        bool has_ds4_queries = false;
        bool has_query42 = false;
        bool has_sensor_id = false;
        bool has_package_id_query = false;
        bool has_build_id_query = false;
        u16 prod_info_addr;
        u8 ds4_query_len;

        ret = rmi_read_block(rmi_dev, query_offset,
                               queries, RMI_F01_BASIC_QUERY_LEN);
        if (ret) {
                dev_err(&rmi_dev->dev,
                        "Failed to read device query registers: %d\n", ret);
                return ret;
        }

        prod_info_addr = query_offset + 17;
        query_offset += RMI_F01_BASIC_QUERY_LEN;

        /* Now parse what we got */
        props->manufacturer_id = queries[0];

        props->has_lts = queries[1] & RMI_F01_QRY1_HAS_LTS;
        props->has_adjustable_doze =
                        queries[1] & RMI_F01_QRY1_HAS_ADJ_DOZE;
        props->has_adjustable_doze_holdoff =
                        queries[1] & RMI_F01_QRY1_HAS_ADJ_DOZE_HOFF;
        has_query42 = queries[1] & RMI_F01_QRY1_HAS_QUERY42;
        has_sensor_id = queries[1] & RMI_F01_QRY1_HAS_SENSOR_ID;

        snprintf(props->dom, sizeof(props->dom), "20%02d/%02d/%02d",
                 queries[5] & RMI_F01_QRY5_YEAR_MASK,
                 queries[6] & RMI_F01_QRY6_MONTH_MASK,
                 queries[7] & RMI_F01_QRY7_DAY_MASK);

        memcpy(props->product_id, &queries[11],
                RMI_PRODUCT_ID_LENGTH);
        props->product_id[RMI_PRODUCT_ID_LENGTH] = '\0';

        props->productinfo =
                        ((queries[2] & RMI_F01_QRY2_PRODINFO_MASK) << 7) |
                        (queries[3] & RMI_F01_QRY2_PRODINFO_MASK);

        if (has_sensor_id)
                query_offset++;

        if (has_query42) {
                ret = rmi_read(rmi_dev, query_offset, queries);
                if (ret) {
                        dev_err(&rmi_dev->dev,
                                "Failed to read query 42 register: %d\n", ret);
                        return ret;
                }

                has_ds4_queries = !!(queries[0] & BIT(0));
                query_offset++;
        }

        if (has_ds4_queries) {
                ret = rmi_read(rmi_dev, query_offset, &ds4_query_len);
                if (ret) {
                        dev_err(&rmi_dev->dev,
                                "Failed to read DS4 queries length: %d\n", ret);
                        return ret;
                }
                query_offset++;

                if (ds4_query_len > 0) {
                        ret = rmi_read(rmi_dev, query_offset, queries);
                        if (ret) {
                                dev_err(&rmi_dev->dev,
                                        "Failed to read DS4 queries: %d\n",
                                        ret);
                                return ret;
                        }

                        has_package_id_query = !!(queries[0] & BIT(0));
                        has_build_id_query = !!(queries[0] & BIT(1));
                }

                if (has_package_id_query) {
                        ret = rmi_read_block(rmi_dev, prod_info_addr,
                                             queries, sizeof(__le64));
                        if (ret) {
                                dev_err(&rmi_dev->dev,
                                        "Failed to read package info: %d\n",
                                        ret);
                                return ret;
                        }

                        props->package_id = get_unaligned_le64(queries);
                        prod_info_addr++;
                }

                if (has_build_id_query) {
                        ret = rmi_read_block(rmi_dev, prod_info_addr, queries,
                                            3);
                        if (ret) {
                                dev_err(&rmi_dev->dev,
                                        "Failed to read product info: %d\n",
                                        ret);
                                return ret;
                        }

                        props->firmware_id = queries[1] << 8 | queries[0];
                        props->firmware_id += queries[2] * 65536;
                }
        }

        return 0;
}

const char *rmi_f01_get_product_ID(struct rmi_function *fn)
{
        struct f01_data *f01 = dev_get_drvdata(&fn->dev);

        return f01->properties.product_id;
}

static ssize_t rmi_driver_manufacturer_id_show(struct device *dev,
                                               struct device_attribute *dattr,
                                               char *buf)
{
        struct rmi_driver_data *data = dev_get_drvdata(dev);
        struct f01_data *f01 = dev_get_drvdata(&data->f01_container->dev);

        return scnprintf(buf, PAGE_SIZE, "%d\n",
                         f01->properties.manufacturer_id);
}

static DEVICE_ATTR(manufacturer_id, 0444,
                   rmi_driver_manufacturer_id_show, NULL);

static ssize_t rmi_driver_dom_show(struct device *dev,
                                   struct device_attribute *dattr, char *buf)
{
        struct rmi_driver_data *data = dev_get_drvdata(dev);
        struct f01_data *f01 = dev_get_drvdata(&data->f01_container->dev);

        return scnprintf(buf, PAGE_SIZE, "%s\n", f01->properties.dom);
}

static DEVICE_ATTR(date_of_manufacture, 0444, rmi_driver_dom_show, NULL);

static ssize_t rmi_driver_product_id_show(struct device *dev,
                                          struct device_attribute *dattr,
                                          char *buf)
{
        struct rmi_driver_data *data = dev_get_drvdata(dev);
        struct f01_data *f01 = dev_get_drvdata(&data->f01_container->dev);

        return scnprintf(buf, PAGE_SIZE, "%s\n", f01->properties.product_id);
}

static DEVICE_ATTR(product_id, 0444, rmi_driver_product_id_show, NULL);

static ssize_t rmi_driver_firmware_id_show(struct device *dev,
                                           struct device_attribute *dattr,
                                           char *buf)
{
        struct rmi_driver_data *data = dev_get_drvdata(dev);
        struct f01_data *f01 = dev_get_drvdata(&data->f01_container->dev);

        return scnprintf(buf, PAGE_SIZE, "%d\n", f01->properties.firmware_id);
}

static DEVICE_ATTR(firmware_id, 0444, rmi_driver_firmware_id_show, NULL);

static ssize_t rmi_driver_package_id_show(struct device *dev,
                                          struct device_attribute *dattr,
                                          char *buf)
{
        struct rmi_driver_data *data = dev_get_drvdata(dev);
        struct f01_data *f01 = dev_get_drvdata(&data->f01_container->dev);

        u32 package_id = f01->properties.package_id;

        return scnprintf(buf, PAGE_SIZE, "%04x.%04x\n",
                         package_id & 0xffff, (package_id >> 16) & 0xffff);
}

static DEVICE_ATTR(package_id, 0444, rmi_driver_package_id_show, NULL);

static struct attribute *rmi_f01_attrs[] = {
        &dev_attr_manufacturer_id.attr,
        &dev_attr_date_of_manufacture.attr,
        &dev_attr_product_id.attr,
        &dev_attr_firmware_id.attr,
        &dev_attr_package_id.attr,
        NULL
};

static const struct attribute_group rmi_f01_attr_group = {
        .attrs = rmi_f01_attrs,
};

static int rmi_f01_probe(struct rmi_function *fn)
{
        struct rmi_device *rmi_dev = fn->rmi_dev;
        struct rmi_driver_data *driver_data = dev_get_drvdata(&rmi_dev->dev);
        struct rmi_device_platform_data *pdata = rmi_get_platform_data(rmi_dev);
        struct f01_data *f01;
        int error;
        u16 ctrl_base_addr = fn->fd.control_base_addr;
        u8 device_status;
        u8 temp;

        f01 = devm_kzalloc(&fn->dev, sizeof(struct f01_data), GFP_KERNEL);
        if (!f01)
                return -ENOMEM;

        f01->num_of_irq_regs = driver_data->num_of_irq_regs;

        /*
         * Set the configured bit and (optionally) other important stuff
         * in the device control register.
         */

        error = rmi_read(rmi_dev, fn->fd.control_base_addr,
                         &f01->device_control.ctrl0);
        if (error) {
                dev_err(&fn->dev, "Failed to read F01 control: %d\n", error);
                return error;
        }

        switch (pdata->power_management.nosleep) {
        case RMI_REG_STATE_DEFAULT:
                break;
        case RMI_REG_STATE_OFF:
                f01->device_control.ctrl0 &= ~RMI_F01_CTRL0_NOSLEEP_BIT;
                break;
        case RMI_REG_STATE_ON:
                f01->device_control.ctrl0 |= RMI_F01_CTRL0_NOSLEEP_BIT;
                break;
        }

        /*
         * Sleep mode might be set as a hangover from a system crash or
         * reboot without power cycle.  If so, clear it so the sensor
         * is certain to function.
         */
        if ((f01->device_control.ctrl0 & RMI_F01_CTRL0_SLEEP_MODE_MASK) !=
                        RMI_SLEEP_MODE_NORMAL) {
                dev_warn(&fn->dev,
                         "WARNING: Non-zero sleep mode found. Clearing...\n");
                f01->device_control.ctrl0 &= ~RMI_F01_CTRL0_SLEEP_MODE_MASK;
        }

        f01->device_control.ctrl0 |= RMI_F01_CTRL0_CONFIGURED_BIT;

        error = rmi_write(rmi_dev, fn->fd.control_base_addr,
                          f01->device_control.ctrl0);
        if (error) {
                dev_err(&fn->dev, "Failed to write F01 control: %d\n", error);
                return error;
        }

        /* Dummy read in order to clear irqs */
        error = rmi_read(rmi_dev, fn->fd.data_base_addr + 1, &temp);
        if (error < 0) {
                dev_err(&fn->dev, "Failed to read Interrupt Status.\n");
                return error;
        }

        error = rmi_f01_read_properties(rmi_dev, fn->fd.query_base_addr,
                                        &f01->properties);
        if (error < 0) {
                dev_err(&fn->dev, "Failed to read F01 properties.\n");
                return error;
        }

        dev_info(&fn->dev, "found RMI device, manufacturer: %s, product: %s, fw id: %d\n",
                 f01->properties.manufacturer_id == 1 ? "Synaptics" : "unknown",
                 f01->properties.product_id, f01->properties.firmware_id);

        /* Advance to interrupt control registers, then skip over them. */
        ctrl_base_addr++;
        ctrl_base_addr += f01->num_of_irq_regs;

        /* read control register */
        if (f01->properties.has_adjustable_doze) {
                f01->doze_interval_addr = ctrl_base_addr;
                ctrl_base_addr++;

                if (pdata->power_management.doze_interval) {
                        f01->device_control.doze_interval =
                                pdata->power_management.doze_interval;
                        error = rmi_write(rmi_dev, f01->doze_interval_addr,
                                          f01->device_control.doze_interval);
                        if (error) {
                                dev_err(&fn->dev,
                                        "Failed to configure F01 doze interval register: %d\n",
                                        error);
                                return error;
                        }
                } else {
                        error = rmi_read(rmi_dev, f01->doze_interval_addr,
                                         &f01->device_control.doze_interval);
                        if (error) {
                                dev_err(&fn->dev,
                                        "Failed to read F01 doze interval register: %d\n",
                                        error);
                                return error;
                        }
                }

                f01->wakeup_threshold_addr = ctrl_base_addr;
                ctrl_base_addr++;

                if (pdata->power_management.wakeup_threshold) {
                        f01->device_control.wakeup_threshold =
                                pdata->power_management.wakeup_threshold;
                        error = rmi_write(rmi_dev, f01->wakeup_threshold_addr,
                                          f01->device_control.wakeup_threshold);
                        if (error) {
                                dev_err(&fn->dev,
                                        "Failed to configure F01 wakeup threshold register: %d\n",
                                        error);
                                return error;
                        }
                } else {
                        error = rmi_read(rmi_dev, f01->wakeup_threshold_addr,
                                         &f01->device_control.wakeup_threshold);
                        if (error < 0) {
                                dev_err(&fn->dev,
                                        "Failed to read F01 wakeup threshold register: %d\n",
                                        error);
                                return error;
                        }
                }
        }

        if (f01->properties.has_lts)
                ctrl_base_addr++;

        if (f01->properties.has_adjustable_doze_holdoff) {
                f01->doze_holdoff_addr = ctrl_base_addr;
                ctrl_base_addr++;

                if (pdata->power_management.doze_holdoff) {
                        f01->device_control.doze_holdoff =
                                pdata->power_management.doze_holdoff;
                        error = rmi_write(rmi_dev, f01->doze_holdoff_addr,
                                          f01->device_control.doze_holdoff);
                        if (error) {
                                dev_err(&fn->dev,
                                        "Failed to configure F01 doze holdoff register: %d\n",
                                        error);
                                return error;
                        }
                } else {
                        error = rmi_read(rmi_dev, f01->doze_holdoff_addr,
                                         &f01->device_control.doze_holdoff);
                        if (error) {
                                dev_err(&fn->dev,
                                        "Failed to read F01 doze holdoff register: %d\n",
                                        error);
                                return error;
                        }
                }
        }

        error = rmi_read(rmi_dev, fn->fd.data_base_addr, &device_status);
        if (error < 0) {
                dev_err(&fn->dev,
                        "Failed to read device status: %d\n", error);
                return error;
        }

        if (RMI_F01_STATUS_UNCONFIGURED(device_status)) {
                dev_err(&fn->dev,
                        "Device was reset during configuration process, status: %#02x!\n",
                        RMI_F01_STATUS_CODE(device_status));
                return -EINVAL;
        }

        dev_set_drvdata(&fn->dev, f01);

        error = sysfs_create_group(&fn->rmi_dev->dev.kobj, &rmi_f01_attr_group);
        if (error)
                dev_warn(&fn->dev, "Failed to create sysfs group: %d\n", error);

        return 0;
}

static void rmi_f01_remove(struct rmi_function *fn)
{
        sysfs_remove_group(&fn->rmi_dev->dev.kobj, &rmi_f01_attr_group);
}

static int rmi_f01_config(struct rmi_function *fn)
{
        struct f01_data *f01 = dev_get_drvdata(&fn->dev);
        int error;

        error = rmi_write(fn->rmi_dev, fn->fd.control_base_addr,
                          f01->device_control.ctrl0);
        if (error) {
                dev_err(&fn->dev,
                        "Failed to write device_control register: %d\n", error);
                return error;
        }

        if (f01->properties.has_adjustable_doze) {
                error = rmi_write(fn->rmi_dev, f01->doze_interval_addr,
                                  f01->device_control.doze_interval);
                if (error) {
                        dev_err(&fn->dev,
                                "Failed to write doze interval: %d\n", error);
                        return error;
                }

                error = rmi_write_block(fn->rmi_dev,
                                         f01->wakeup_threshold_addr,
                                         &f01->device_control.wakeup_threshold,
                                         sizeof(u8));
                if (error) {
                        dev_err(&fn->dev,
                                "Failed to write wakeup threshold: %d\n",
                                error);
                        return error;
                }
        }

        if (f01->properties.has_adjustable_doze_holdoff) {
                error = rmi_write(fn->rmi_dev, f01->doze_holdoff_addr,
                                  f01->device_control.doze_holdoff);
                if (error) {
                        dev_err(&fn->dev,
                                "Failed to write doze holdoff: %d\n", error);
                        return error;
                }
        }

        return 0;
}

static int rmi_f01_suspend(struct rmi_function *fn)
{
        struct f01_data *f01 = dev_get_drvdata(&fn->dev);
        int error;

        f01->old_nosleep =
                f01->device_control.ctrl0 & RMI_F01_CTRL0_NOSLEEP_BIT;
        f01->device_control.ctrl0 &= ~RMI_F01_CTRL0_NOSLEEP_BIT;

        f01->device_control.ctrl0 &= ~RMI_F01_CTRL0_SLEEP_MODE_MASK;
        if (device_may_wakeup(fn->rmi_dev->xport->dev))
                f01->device_control.ctrl0 |= RMI_SLEEP_MODE_RESERVED1;
        else
                f01->device_control.ctrl0 |= RMI_SLEEP_MODE_SENSOR_SLEEP;

        error = rmi_write(fn->rmi_dev, fn->fd.control_base_addr,
                          f01->device_control.ctrl0);
        if (error) {
                dev_err(&fn->dev, "Failed to write sleep mode: %d.\n", error);
                if (f01->old_nosleep)
                        f01->device_control.ctrl0 |= RMI_F01_CTRL0_NOSLEEP_BIT;
                f01->device_control.ctrl0 &= ~RMI_F01_CTRL0_SLEEP_MODE_MASK;
                f01->device_control.ctrl0 |= RMI_SLEEP_MODE_NORMAL;
                return error;
        }

        return 0;
}

static int rmi_f01_resume(struct rmi_function *fn)
{
        struct f01_data *f01 = dev_get_drvdata(&fn->dev);
        int error;

        if (f01->old_nosleep)
                f01->device_control.ctrl0 |= RMI_F01_CTRL0_NOSLEEP_BIT;

        f01->device_control.ctrl0 &= ~RMI_F01_CTRL0_SLEEP_MODE_MASK;
        f01->device_control.ctrl0 |= RMI_SLEEP_MODE_NORMAL;

        error = rmi_write(fn->rmi_dev, fn->fd.control_base_addr,
                          f01->device_control.ctrl0);
        if (error) {
                dev_err(&fn->dev,
                        "Failed to restore normal operation: %d.\n", error);
                return error;
        }

        return 0;
}

static int rmi_f01_attention(struct rmi_function *fn,
                             unsigned long *irq_bits)
{
        struct rmi_device *rmi_dev = fn->rmi_dev;
        int error;
        u8 device_status;

        error = rmi_read(rmi_dev, fn->fd.data_base_addr, &device_status);
        if (error) {
                dev_err(&fn->dev,
                        "Failed to read device status: %d.\n", error);
                return error;
        }

        if (RMI_F01_STATUS_UNCONFIGURED(device_status)) {
                dev_warn(&fn->dev, "Device reset detected.\n");
                error = rmi_dev->driver->reset_handler(rmi_dev);
                if (error) {
                        dev_err(&fn->dev, "Device reset failed: %d\n", error);
                        return error;
                }
        }

        return 0;
}

struct rmi_function_handler rmi_f01_handler = {
        .driver = {
                .name   = "rmi4_f01",
                /*
                 * Do not allow user unbinding F01 as it is critical
                 * function.
                 */
                .suppress_bind_attrs = true,
        },
        .func           = 0x01,
        .probe          = rmi_f01_probe,
        .remove         = rmi_f01_remove,
        .config         = rmi_f01_config,
        .attention      = rmi_f01_attention,
        .suspend        = rmi_f01_suspend,
        .resume         = rmi_f01_resume,
};