// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2012-2016 Synaptics Incorporated
 */
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/rmi.h>
#include <linux/sizes.h>
#include <linux/unaligned.h>
#include "rmi_driver.h"
#include "rmi_2d_sensor.h"

enum rmi_f12_object_type {
        RMI_F12_OBJECT_NONE                     = 0x00,
        RMI_F12_OBJECT_FINGER                   = 0x01,
        RMI_F12_OBJECT_STYLUS                   = 0x02,
        RMI_F12_OBJECT_PALM                     = 0x03,
        RMI_F12_OBJECT_UNCLASSIFIED             = 0x04,
        RMI_F12_OBJECT_GLOVED_FINGER            = 0x06,
        RMI_F12_OBJECT_NARROW_OBJECT            = 0x07,
        RMI_F12_OBJECT_HAND_EDGE                = 0x08,
        RMI_F12_OBJECT_COVER                    = 0x0A,
        RMI_F12_OBJECT_STYLUS_2                 = 0x0B,
        RMI_F12_OBJECT_ERASER                   = 0x0C,
        RMI_F12_OBJECT_SMALL_OBJECT             = 0x0D,
};

#define F12_DATA1_BYTES_PER_OBJ                 8
#define RMI_F12_QUERY_RESOLUTION                29

struct f12_data {
        struct rmi_2d_sensor sensor;
        struct rmi_2d_sensor_platform_data sensor_pdata;
        bool has_dribble;

        u16 data_addr;

        struct rmi_register_descriptor query_reg_desc;
        struct rmi_register_descriptor control_reg_desc;
        struct rmi_register_descriptor data_reg_desc;

        /* F12 Data1 describes sensed objects */
        const struct rmi_register_desc_item *data1;
        u16 data1_offset;

        /* F12 Data5 describes finger ACM */
        const struct rmi_register_desc_item *data5;
        u16 data5_offset;

        /* F12 Data5 describes Pen */
        const struct rmi_register_desc_item *data6;
        u16 data6_offset;

        /* F12 Data9 reports relative data */
        const struct rmi_register_desc_item *data9;
        u16 data9_offset;

        const struct rmi_register_desc_item *data15;
        u16 data15_offset;

        unsigned long irq_mask[];
};

static int rmi_f12_read_register_descs(struct rmi_function *fn,
                                       struct f12_data *f12, u16 query_addr)
{
        struct {
                struct rmi_register_descriptor *desc;
                const char *name;
        } descriptors[] = {
                { &f12->query_reg_desc, "Query" },
                { &f12->control_reg_desc, "Control" },
                { &f12->data_reg_desc, "Data" },
        };
        struct rmi_device *rmi_dev = fn->rmi_dev;
        int error;
        int i;

        for (i = 0; i < ARRAY_SIZE(descriptors); i++) {
                error = rmi_read_register_desc(rmi_dev, query_addr,
                                               descriptors[i].desc);
                if (error) {
                        dev_err(&fn->dev,
                                "Failed to read the %s Register Descriptor: %d\n",
                                descriptors[i].name, error);
                        return error;
                }
                query_addr += 3;
        }

        return 0;
}

static int rmi_f12_read_sensor_tuning(struct f12_data *f12)
{
        const struct rmi_register_desc_item *item;
        struct rmi_2d_sensor *sensor = &f12->sensor;
        struct rmi_function *fn = sensor->fn;
        struct rmi_device *rmi_dev = fn->rmi_dev;
        int ret;
        int offset;
        u8 buf[15];
        int pitch_x = 0;
        int pitch_y = 0;
        int rx_receivers = 0;
        int tx_receivers = 0;
        u16 query_dpm_addr = 0;
        int dpm_resolution = 0;

        item = rmi_get_register_desc_item(&f12->control_reg_desc, 8);
        if (!item) {
                dev_err(&fn->dev,
                        "F12 does not have the sensor tuning control register\n");
                return -ENODEV;
        }

        offset = rmi_register_desc_calc_reg_offset(&f12->control_reg_desc, 8);

        if (item->reg_size > sizeof(buf)) {
                dev_err(&fn->dev,
                        "F12 control8 should be no bigger than %zd bytes, not: %u\n",
                        sizeof(buf), item->reg_size);
                return -ENODEV;
        }

        ret = rmi_read_block(rmi_dev, fn->fd.control_base_addr + offset,
                             buf, item->reg_size);
        if (ret)
                return ret;

        offset = 0;
        if (rmi_register_desc_has_subpacket(item, 0)) {
                sensor->max_x = get_unaligned_le16(&buf[offset]);
                sensor->max_y = get_unaligned_le16(&buf[offset + 2]);
                offset += 4;
        }

        rmi_dbg(RMI_DEBUG_FN, &fn->dev, "%s: max_x: %d max_y: %d\n", __func__,
                sensor->max_x, sensor->max_y);

        if (rmi_register_desc_has_subpacket(item, 1)) {
                pitch_x = get_unaligned_le16(&buf[offset]);
                pitch_y = get_unaligned_le16(&buf[offset + 2]);
                offset += 4;
        }

        if (rmi_register_desc_has_subpacket(item, 2)) {
                /* Units 1/128 sensor pitch */
                rmi_dbg(RMI_DEBUG_FN, &fn->dev,
                        "%s: Inactive Border xlo:%d xhi:%d ylo:%d yhi:%d\n",
                        __func__,
                        buf[offset], buf[offset + 1],
                        buf[offset + 2], buf[offset + 3]);

                offset += 4;
        }

        /*
         * Use the Query DPM feature when the resolution query register
         * exists.
         */
        if (rmi_get_register_desc_item(&f12->query_reg_desc,
                                       RMI_F12_QUERY_RESOLUTION)) {
                offset = rmi_register_desc_calc_reg_offset(&f12->query_reg_desc,
                                                           RMI_F12_QUERY_RESOLUTION);
                query_dpm_addr = fn->fd.query_base_addr + offset;
                ret = rmi_read(fn->rmi_dev, query_dpm_addr, buf);
                if (ret) {
                        dev_err(&fn->dev, "Failed to read DPM value: %d\n", ret);
                        return ret;
                }
                dpm_resolution = buf[0];

                sensor->x_mm = sensor->max_x / dpm_resolution;
                sensor->y_mm = sensor->max_y / dpm_resolution;
        } else {
                if (rmi_register_desc_has_subpacket(item, 3)) {
                        rx_receivers = buf[offset];
                        tx_receivers = buf[offset + 1];
                        offset += 2;
                }

                /* Skip over sensor flags */
                if (rmi_register_desc_has_subpacket(item, 4))
                        offset += 1;

                sensor->x_mm = (pitch_x * rx_receivers) >> 12;
                sensor->y_mm = (pitch_y * tx_receivers) >> 12;
        }

        rmi_dbg(RMI_DEBUG_FN, &fn->dev, "%s: x_mm: %d y_mm: %d\n", __func__,
                sensor->x_mm, sensor->y_mm);

        return 0;
}

static void rmi_f12_process_objects(struct f12_data *f12, u8 *data1, u32 size)
{
        struct rmi_2d_sensor *sensor = &f12->sensor;
        u32 objects = min(f12->data1->num_subpackets, size / F12_DATA1_BYTES_PER_OBJ);
        int i;

        for (i = 0; i < objects; i++) {
                struct rmi_2d_sensor_abs_object *obj = &sensor->objs[i];

                obj->type = RMI_2D_OBJECT_NONE;
                obj->mt_tool = MT_TOOL_FINGER;

                switch (data1[0]) {
                case RMI_F12_OBJECT_FINGER:
                        obj->type = RMI_2D_OBJECT_FINGER;
                        break;
                case RMI_F12_OBJECT_STYLUS:
                        obj->type = RMI_2D_OBJECT_STYLUS;
                        obj->mt_tool = MT_TOOL_PEN;
                        break;
                case RMI_F12_OBJECT_PALM:
                        obj->type = RMI_2D_OBJECT_PALM;
                        obj->mt_tool = MT_TOOL_PALM;
                        break;
                case RMI_F12_OBJECT_UNCLASSIFIED:
                        obj->type = RMI_2D_OBJECT_UNCLASSIFIED;
                        break;
                }

                obj->x = get_unaligned_le16(&data1[1]);
                obj->y = get_unaligned_le16(&data1[3]);
                obj->z = data1[5];
                obj->wx = data1[6];
                obj->wy = data1[7];

                rmi_2d_sensor_abs_process(sensor, obj, i);

                data1 += F12_DATA1_BYTES_PER_OBJ;
        }

        if (sensor->kernel_tracking)
                input_mt_assign_slots(sensor->input,
                                      sensor->tracking_slots,
                                      sensor->tracking_pos,
                                      sensor->nbr_fingers,
                                      sensor->dmax);

        for (i = 0; i < objects; i++)
                rmi_2d_sensor_abs_report(sensor, &sensor->objs[i], i);
}

static irqreturn_t rmi_f12_attention(int irq, void *ctx)
{
        struct rmi_function *fn = ctx;
        struct rmi_device *rmi_dev = fn->rmi_dev;
        struct rmi_driver_data *drvdata = dev_get_drvdata(&rmi_dev->dev);
        struct f12_data *f12 = dev_get_drvdata(&fn->dev);
        struct rmi_2d_sensor *sensor = &f12->sensor;
        u32 valid_bytes = sensor->pkt_size;
        int retval;

        if (drvdata->attn_data.data) {
                valid_bytes = min_t(u32, sensor->attn_size, drvdata->attn_data.size);
                memcpy(sensor->data_pkt, drvdata->attn_data.data, valid_bytes);
                drvdata->attn_data.data += valid_bytes;
                drvdata->attn_data.size -= valid_bytes;
        } else {
                retval = rmi_read_block(rmi_dev, f12->data_addr,
                                        sensor->data_pkt, sensor->pkt_size);
                if (retval < 0) {
                        dev_err(&fn->dev, "Failed to read object data. Code: %d.\n",
                                retval);
                        return IRQ_RETVAL(retval);
                }
        }

        if (f12->data1)
                rmi_f12_process_objects(f12, &sensor->data_pkt[f12->data1_offset],
                                        valid_bytes);

        input_mt_sync_frame(sensor->input);

        return IRQ_HANDLED;
}

static int rmi_f12_update_dribble(struct rmi_function *fn, struct f12_data *f12)
{
        const struct rmi_register_desc_item *item;
        struct rmi_device *rmi_dev = fn->rmi_dev;
        u8 subpacket_offset = 0;
        u16 control_offset;
        u32 control_size;
        int error;
        u8 buf[3];

        item = rmi_get_register_desc_item(&f12->control_reg_desc, 20);
        if (!item)
                return 0;

        control_offset = rmi_register_desc_calc_reg_offset(&f12->control_reg_desc, 20);

        /*
         * The byte containing the EnableDribble bit will be
         * in either byte 0 or byte 2 of control 20. Depending
         * on the existence of subpacket 0. If control 20 is
         * larger then 3 bytes, just read the first 3.
         */
        control_size = min(item->reg_size, 3U);

        error = rmi_read_block(rmi_dev, fn->fd.control_base_addr + control_offset,
                               buf, control_size);
        if (error)
                return error;

        if (rmi_register_desc_has_subpacket(item, 0))
                subpacket_offset += 1;

        switch (f12->sensor.dribble) {
        case RMI_REG_STATE_OFF:
                buf[subpacket_offset] &= ~BIT(2);
                break;
        case RMI_REG_STATE_ON:
                buf[subpacket_offset] |= BIT(2);
                break;
        case RMI_REG_STATE_DEFAULT:
        default:
                break;
        }

        error = rmi_write_block(rmi_dev, fn->fd.control_base_addr + control_offset,
                                buf, control_size);
        if (error)
                return error;

        return 0;
}

static int rmi_f12_write_control_regs(struct rmi_function *fn)
{
        struct f12_data *f12 = dev_get_drvdata(&fn->dev);

        if (f12->has_dribble && f12->sensor.dribble != RMI_REG_STATE_DEFAULT)
                return rmi_f12_update_dribble(fn, f12);

        return 0;
}

static int rmi_f12_config(struct rmi_function *fn)
{
        struct rmi_driver *drv = fn->rmi_dev->driver;
        struct f12_data *f12 = dev_get_drvdata(&fn->dev);
        struct rmi_driver_data *drvdata = dev_get_drvdata(&fn->rmi_dev->dev);
        int irq_mask_size = BITS_TO_LONGS(drvdata->irq_count);
        unsigned long *abs_mask = f12->irq_mask;
        unsigned long *rel_mask = f12->irq_mask + irq_mask_size;
        struct rmi_2d_sensor *sensor;
        int ret;

        sensor = &f12->sensor;

        if (!sensor->report_abs)
                drv->clear_irq_bits(fn->rmi_dev, abs_mask);
        else
                drv->set_irq_bits(fn->rmi_dev, abs_mask);

        drv->clear_irq_bits(fn->rmi_dev, rel_mask);

        ret = rmi_f12_write_control_regs(fn);
        if (ret)
                dev_warn(&fn->dev,
                         "Failed to write F12 control registers: %d\n", ret);

        return 0;
}

static int rmi_f12_probe(struct rmi_function *fn)
{
        struct f12_data *f12;
        int ret;
        struct rmi_device *rmi_dev = fn->rmi_dev;
        char buf;
        u16 query_addr = fn->fd.query_base_addr;
        const struct rmi_register_desc_item *item;
        struct rmi_2d_sensor *sensor;
        struct rmi_device_platform_data *pdata = rmi_get_platform_data(rmi_dev);
        struct rmi_driver_data *drvdata = dev_get_drvdata(&rmi_dev->dev);
        size_t data_offset = 0;
        size_t pkt_size;
        int irq_mask_size;
        int i;

        rmi_dbg(RMI_DEBUG_FN, &fn->dev, "%s\n", __func__);

        irq_mask_size = BITS_TO_LONGS(drvdata->irq_count);

        ret = rmi_read(fn->rmi_dev, query_addr, &buf);
        if (ret < 0) {
                dev_err(&fn->dev, "Failed to read general info register: %d\n",
                        ret);
                return -ENODEV;
        }
        ++query_addr;

        if (!(buf & BIT(0))) {
                dev_err(&fn->dev,
                        "Behavior of F12 without register descriptors is undefined.\n");
                return -ENODEV;
        }

        f12 = devm_kzalloc(&fn->dev, struct_size(f12, irq_mask, irq_mask_size * 2),
                           GFP_KERNEL);
        if (!f12)
                return -ENOMEM;

        set_bit(fn->irq_pos, f12->irq_mask);
        set_bit(fn->irq_pos + 1, f12->irq_mask + irq_mask_size);

        f12->has_dribble = !!(buf & BIT(3));

        if (fn->dev.of_node) {
                ret = rmi_2d_sensor_of_probe(&fn->dev, &f12->sensor_pdata);
                if (ret)
                        return ret;
        } else {
                f12->sensor_pdata = pdata->sensor_pdata;
        }

        ret = rmi_f12_read_register_descs(fn, f12, query_addr);
        if (ret)
                return ret;

        sensor = &f12->sensor;
        sensor->fn = fn;
        f12->data_addr = fn->fd.data_base_addr;
        pkt_size = rmi_register_desc_calc_size(&f12->data_reg_desc);
        if (pkt_size > SZ_1M) {
                dev_err(&fn->dev, "Invalid data packet size: %zu\n", pkt_size);
                return -EINVAL;
        }
        sensor->pkt_size = pkt_size;

        sensor->axis_align = f12->sensor_pdata.axis_align;

        sensor->x_mm = f12->sensor_pdata.x_mm;
        sensor->y_mm = f12->sensor_pdata.y_mm;
        sensor->dribble = f12->sensor_pdata.dribble;

        if (sensor->sensor_type == rmi_sensor_default)
                sensor->sensor_type = f12->sensor_pdata.sensor_type;

        rmi_dbg(RMI_DEBUG_FN, &fn->dev, "%s: data packet size: %u\n", __func__,
                sensor->pkt_size);
        sensor->data_pkt = devm_kmalloc(&fn->dev, sensor->pkt_size, GFP_KERNEL);
        if (!sensor->data_pkt)
                return -ENOMEM;

        dev_set_drvdata(&fn->dev, f12);

        ret = rmi_f12_read_sensor_tuning(f12);
        if (ret)
                return ret;

        /*
         * Identify available data registers and calculate their offsets within
         * the attention report. For HID devices, only Data1 and Data5 are
         * included in the report; other registers may be described but are
         * not transmitted in the attention packet and thus skipped here.
         */
        for (i = 0; i < 16; i++) {
                item = rmi_get_register_desc_item(&f12->data_reg_desc, i);
                if (!item)
                        continue;

                /* HID attention reports only contain Data1 and Data5 */
                if (drvdata->attn_data.data && i != 1 && i != 5)
                        continue;

                if (data_offset > U16_MAX) {
                        dev_err(&fn->dev, "Invalid offset for data%d: %zu\n",
                                i, data_offset);
                        return -EINVAL;
                }

                switch (i) {
                case 1:
                        f12->data1 = item;
                        f12->data1_offset = data_offset;

                        if (item->num_subpackets > 255) {
                                dev_err(&fn->dev,
                                        "Too many fingers declared: %d\n",
                                        item->num_subpackets);
                                return -EINVAL;
                        }

                        sensor->nbr_fingers = item->num_subpackets;
                        sensor->report_abs = 1;
                        sensor->attn_size += item->reg_size;
                        break;

                case 5:
                        f12->data5 = item;
                        f12->data5_offset = data_offset;
                        sensor->attn_size += item->reg_size;
                        break;

                case 6:
                        f12->data6 = item;
                        f12->data6_offset = data_offset;
                        break;

                case 9:
                        f12->data9 = item;
                        f12->data9_offset = data_offset;
                        if (!sensor->report_abs)
                                sensor->report_rel = 1;
                        break;

                case 15:
                        f12->data15 = item;
                        f12->data15_offset = data_offset;
                        break;
                }

                data_offset += item->reg_size;
        }

        /* allocate the in-kernel tracking buffers */
        sensor->tracking_pos = devm_kcalloc(&fn->dev, sensor->nbr_fingers,
                                            sizeof(*sensor->tracking_pos),
                                            GFP_KERNEL);
        if (!sensor->tracking_pos)
                return -ENOMEM;

        sensor->tracking_slots = devm_kcalloc(&fn->dev, sensor->nbr_fingers,
                                              sizeof(*sensor->tracking_slots),
                                              GFP_KERNEL);
        if (!sensor->tracking_slots)
                return -ENOMEM;

        sensor->objs = devm_kcalloc(&fn->dev, sensor->nbr_fingers,
                                    sizeof(*sensor->objs), GFP_KERNEL);
        if (!sensor->objs)
                return -ENOMEM;

        ret = rmi_2d_sensor_configure_input(fn, sensor);
        if (ret)
                return ret;

        return 0;
}

struct rmi_function_handler rmi_f12_handler = {
        .driver = {
                .name = "rmi4_f12",
        },
        .func = 0x12,
        .probe = rmi_f12_probe,
        .config = rmi_f12_config,
        .attention = rmi_f12_attention,
};