// SPDX-License-Identifier: GPL-2.0-or-later

/*
 *
 * cx88-i2c.c  --  all the i2c code is here
 *
 * Copyright (C) 1996,97,98 Ralph  Metzler (rjkm@thp.uni-koeln.de)
 *                         & Marcus Metzler (mocm@thp.uni-koeln.de)
 * (c) 2002 Yurij Sysoev <yurij@naturesoft.net>
 * (c) 1999-2003 Gerd Knorr <kraxel@bytesex.org>
 * (c) 2005 Mauro Carvalho Chehab <mchehab@kernel.org>
 *      - Multituner support and i2c address binding
 */

#include "cx88.h"

#include <linux/init.h>
#include <linux/io.h>
#include <linux/module.h>

#include <media/v4l2-common.h>

static unsigned int i2c_debug;
module_param(i2c_debug, int, 0644);
MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");

static unsigned int i2c_scan;
module_param(i2c_scan, int, 0444);
MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");

static unsigned int i2c_udelay = 5;
module_param(i2c_udelay, int, 0644);
MODULE_PARM_DESC(i2c_udelay,
                 "i2c delay at insmod time, in usecs (should be 5 or higher). Lower value means higher bus speed.");

#define dprintk(level, fmt, arg...) do {                                \
        if (i2c_debug >= level)                                         \
                printk(KERN_DEBUG pr_fmt("%s: i2c:" fmt),               \
                        __func__, ##arg);                               \
} while (0)

/* ----------------------------------------------------------------------- */

static void cx8800_bit_setscl(void *data, int state)
{
        struct cx88_core *core = data;

        if (state)
                core->i2c_state |= 0x02;
        else
                core->i2c_state &= ~0x02;
        cx_write(MO_I2C, core->i2c_state);
        cx_read(MO_I2C);
}

static void cx8800_bit_setsda(void *data, int state)
{
        struct cx88_core *core = data;

        if (state)
                core->i2c_state |= 0x01;
        else
                core->i2c_state &= ~0x01;
        cx_write(MO_I2C, core->i2c_state);
        cx_read(MO_I2C);
}

static int cx8800_bit_getscl(void *data)
{
        struct cx88_core *core = data;
        u32 state;

        state = cx_read(MO_I2C);
        return state & 0x02 ? 1 : 0;
}

static int cx8800_bit_getsda(void *data)
{
        struct cx88_core *core = data;
        u32 state;

        state = cx_read(MO_I2C);
        return state & 0x01;
}

/* ----------------------------------------------------------------------- */

static const struct i2c_algo_bit_data cx8800_i2c_algo_template = {
        .setsda  = cx8800_bit_setsda,
        .setscl  = cx8800_bit_setscl,
        .getsda  = cx8800_bit_getsda,
        .getscl  = cx8800_bit_getscl,
        .udelay  = 16,
        .timeout = 200,
};

/* ----------------------------------------------------------------------- */

static const char * const i2c_devs[128] = {
        [0x1c >> 1] = "lgdt330x",
        [0x86 >> 1] = "tda9887/cx22702",
        [0xa0 >> 1] = "eeprom",
        [0xc0 >> 1] = "tuner (analog)",
        [0xc2 >> 1] = "tuner (analog/dvb)",
        [0xc8 >> 1] = "xc5000",
};

static void do_i2c_scan(const char *name, struct i2c_client *c)
{
        unsigned char buf;
        int i, rc;

        for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) {
                c->addr = i;
                rc = i2c_master_recv(c, &buf, 0);
                if (rc < 0)
                        continue;
                pr_info("i2c scan: found device @ 0x%x  [%s]\n",
                        i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
        }
}

/* init + register i2c adapter */
int cx88_i2c_init(struct cx88_core *core, struct pci_dev *pci)
{
        /* Prevents usage of invalid delay values */
        if (i2c_udelay < 5)
                i2c_udelay = 5;

        core->i2c_algo = cx8800_i2c_algo_template;

        core->i2c_adap.dev.parent = &pci->dev;
        strscpy(core->i2c_adap.name, core->name, sizeof(core->i2c_adap.name));
        core->i2c_adap.owner = THIS_MODULE;
        core->i2c_algo.udelay = i2c_udelay;
        core->i2c_algo.data = core;
        i2c_set_adapdata(&core->i2c_adap, &core->v4l2_dev);
        core->i2c_adap.algo_data = &core->i2c_algo;
        core->i2c_client.adapter = &core->i2c_adap;
        strscpy(core->i2c_client.name, "cx88xx internal", I2C_NAME_SIZE);

        cx8800_bit_setscl(core, 1);
        cx8800_bit_setsda(core, 1);

        core->i2c_rc = i2c_bit_add_bus(&core->i2c_adap);
        if (core->i2c_rc == 0) {
                static u8 tuner_data[] = {
                        0x0b, 0xdc, 0x86, 0x52 };
                static struct i2c_msg tuner_msg = {
                        .flags = 0,
                        .addr = 0xc2 >> 1,
                        .buf = tuner_data,
                        .len = 4
                };

                dprintk(1, "i2c register ok\n");
                switch (core->boardnr) {
                case CX88_BOARD_HAUPPAUGE_HVR1300:
                case CX88_BOARD_HAUPPAUGE_HVR3000:
                case CX88_BOARD_HAUPPAUGE_HVR4000:
                        pr_info("i2c init: enabling analog demod on HVR1300/3000/4000 tuner\n");
                        i2c_transfer(core->i2c_client.adapter, &tuner_msg, 1);
                        break;
                default:
                        break;
                }
                if (i2c_scan)
                        do_i2c_scan(core->name, &core->i2c_client);
        } else
                pr_err("i2c register FAILED\n");

        return core->i2c_rc;
}