// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * lnbh25.c
 *
 * Driver for LNB supply and control IC LNBH25
 *
 * Copyright (C) 2014 NetUP Inc.
 * Copyright (C) 2014 Sergey Kozlov <serjk@netup.ru>
 * Copyright (C) 2014 Abylay Ospan <aospan@netup.ru>
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/slab.h>

#include <media/dvb_frontend.h>
#include "lnbh25.h"

/**
 * struct lnbh25_priv - LNBH25 driver private data
 * @i2c:                pointer to the I2C adapter structure
 * @i2c_address:        I2C address of LNBH25 SEC chip
 * @config:             Registers configuration:
 *                      offset 0: 1st register address, always 0x02 (DATA1)
 *                      offset 1: DATA1 register value
 *                      offset 2: DATA2 register value
 */
struct lnbh25_priv {
        struct i2c_adapter      *i2c;
        u8                      i2c_address;
        u8                      config[3];
};

#define LNBH25_STATUS_OFL       0x1
#define LNBH25_STATUS_VMON      0x4
#define LNBH25_VSEL_13          0x03
#define LNBH25_VSEL_18          0x0a

static int lnbh25_read_vmon(struct lnbh25_priv *priv)
{
        int i, ret;
        u8 addr = 0x00;
        u8 status[6];
        struct i2c_msg msg[2] = {
                {
                        .addr = priv->i2c_address,
                        .flags = 0,
                        .len = 1,
                        .buf = &addr
                }, {
                        .addr = priv->i2c_address,
                        .flags = I2C_M_RD,
                        .len = sizeof(status),
                        .buf = status
                }
        };

        for (i = 0; i < 2; i++) {
                ret = i2c_transfer(priv->i2c, &msg[i], 1);
                if (ret >= 0 && ret != 1)
                        ret = -EIO;
                if (ret < 0) {
                        dev_dbg(&priv->i2c->dev,
                                "%s(): I2C transfer %d failed (%d)\n",
                                __func__, i, ret);
                        return ret;
                }
        }
        dev_dbg(&priv->i2c->dev, "%s(): %*ph\n",
                __func__, (int) sizeof(status), status);
        if ((status[0] & (LNBH25_STATUS_OFL | LNBH25_STATUS_VMON)) != 0) {
                dev_err(&priv->i2c->dev,
                        "%s(): voltage in failure state, status reg 0x%x\n",
                        __func__, status[0]);
                return -EIO;
        }
        return 0;
}

static int lnbh25_set_voltage(struct dvb_frontend *fe,
                              enum fe_sec_voltage voltage)
{
        int ret;
        u8 data1_reg;
        const char *vsel;
        struct lnbh25_priv *priv = fe->sec_priv;
        struct i2c_msg msg = {
                .addr = priv->i2c_address,
                .flags = 0,
                .len = sizeof(priv->config),
                .buf = priv->config
        };

        switch (voltage) {
        case SEC_VOLTAGE_OFF:
                data1_reg = 0x00;
                vsel = "Off";
                break;
        case SEC_VOLTAGE_13:
                data1_reg = LNBH25_VSEL_13;
                vsel = "13V";
                break;
        case SEC_VOLTAGE_18:
                data1_reg = LNBH25_VSEL_18;
                vsel = "18V";
                break;
        default:
                return -EINVAL;
        }
        priv->config[1] = data1_reg;
        dev_dbg(&priv->i2c->dev,
                "%s(): %s, I2C 0x%x write [ %02x %02x %02x ]\n",
                __func__, vsel, priv->i2c_address,
                priv->config[0], priv->config[1], priv->config[2]);
        ret = i2c_transfer(priv->i2c, &msg, 1);
        if (ret >= 0 && ret != 1)
                ret = -EIO;
        if (ret < 0) {
                dev_err(&priv->i2c->dev, "%s(): I2C transfer error (%d)\n",
                        __func__, ret);
                return ret;
        }
        if (voltage != SEC_VOLTAGE_OFF) {
                msleep(120);
                ret = lnbh25_read_vmon(priv);
        } else {
                msleep(20);
                ret = 0;
        }
        return ret;
}

static void lnbh25_release(struct dvb_frontend *fe)
{
        struct lnbh25_priv *priv = fe->sec_priv;

        dev_dbg(&priv->i2c->dev, "%s()\n", __func__);
        lnbh25_set_voltage(fe, SEC_VOLTAGE_OFF);
        kfree(fe->sec_priv);
        fe->sec_priv = NULL;
}

struct dvb_frontend *lnbh25_attach(struct dvb_frontend *fe,
                                   struct lnbh25_config *cfg,
                                   struct i2c_adapter *i2c)
{
        struct lnbh25_priv *priv;

        dev_dbg(&i2c->dev, "%s()\n", __func__);
        priv = kzalloc_obj(struct lnbh25_priv);
        if (!priv)
                return NULL;
        priv->i2c_address = (cfg->i2c_address >> 1);
        priv->i2c = i2c;
        priv->config[0] = 0x02;
        priv->config[1] = 0x00;
        priv->config[2] = cfg->data2_config;
        fe->sec_priv = priv;
        if (lnbh25_set_voltage(fe, SEC_VOLTAGE_OFF)) {
                dev_err(&i2c->dev,
                        "%s(): no LNBH25 found at I2C addr 0x%02x\n",
                        __func__, priv->i2c_address);
                kfree(priv);
                fe->sec_priv = NULL;
                return NULL;
        }

        fe->ops.release_sec = lnbh25_release;
        fe->ops.set_voltage = lnbh25_set_voltage;

        dev_info(&i2c->dev, "%s(): attached at I2C addr 0x%02x\n",
                __func__, priv->i2c_address);
        return fe;
}
EXPORT_SYMBOL_GPL(lnbh25_attach);

MODULE_DESCRIPTION("ST LNBH25 driver");
MODULE_AUTHOR("info@netup.ru");
MODULE_LICENSE("GPL");