LXR linux/drivers/media/dvb-frontends/lnbh29.c

   1// SPDX-License-Identifier: GPL-2.0
   2//
   3// Driver for LNB supply and control IC STMicroelectronics LNBH29
   4//
   5// Copyright (c) 2018 Socionext Inc.
   6
   7#include <linux/module.h>
   8#include <linux/init.h>
   9#include <linux/slab.h>
  10
  11#include <media/dvb_frontend.h>
  12#include "lnbh29.h"
  13
  14/**
  15 * struct lnbh29_priv - LNBH29 driver private data
  16 * @i2c:         Pointer to the I2C adapter structure
  17 * @i2c_address: I2C address of LNBH29 chip
  18 * @config:      Registers configuration
  19 *               offset 0: 1st register address, always 0x01 (DATA)
  20 *               offset 1: DATA register value
  21 */
  22struct lnbh29_priv {
  23        struct i2c_adapter *i2c;
  24        u8 i2c_address;
  25        u8 config[2];
  26};
  27
  28#define LNBH29_STATUS_OLF     BIT(0)
  29#define LNBH29_STATUS_OTF     BIT(1)
  30#define LNBH29_STATUS_VMON    BIT(2)
  31#define LNBH29_STATUS_PNG     BIT(3)
  32#define LNBH29_STATUS_PDO     BIT(4)
  33#define LNBH29_VSEL_MASK      GENMASK(2, 0)
  34#define LNBH29_VSEL_0         0x00
  35/* Min: 13.188V, Typ: 13.667V, Max:14V */
  36#define LNBH29_VSEL_13        0x03
  37/* Min: 18.158V, Typ: 18.817V, Max:19.475V */
  38#define LNBH29_VSEL_18        0x07
  39
  40static int lnbh29_read_vmon(struct lnbh29_priv *priv)
  41{
  42        u8 addr = 0x00;
  43        u8 status[2];
  44        int ret;
  45        struct i2c_msg msg[2] = {
  46                {
  47                        .addr = priv->i2c_address,
  48                        .flags = 0,
  49                        .len = 1,
  50                        .buf = &addr
  51                }, {
  52                        .addr = priv->i2c_address,
  53                        .flags = I2C_M_RD,
  54                        .len = sizeof(status),
  55                        .buf = status
  56                }
  57        };
  58
  59        ret = i2c_transfer(priv->i2c, msg, 2);
  60        if (ret >= 0 && ret != 2)
  61                ret = -EIO;
  62        if (ret < 0) {
  63                dev_dbg(&priv->i2c->dev, "LNBH29 I2C transfer failed (%d)\n",
  64                        ret);
  65                return ret;
  66        }
  67
  68        if (status[0] & (LNBH29_STATUS_OLF | LNBH29_STATUS_VMON)) {
  69                dev_err(&priv->i2c->dev,
  70                        "LNBH29 voltage in failure state, status reg 0x%x\n",
  71                        status[0]);
  72                return -EIO;
  73        }
  74
  75        return 0;
  76}
  77
  78static int lnbh29_set_voltage(struct dvb_frontend *fe,
  79                              enum fe_sec_voltage voltage)
  80{
  81        struct lnbh29_priv *priv = fe->sec_priv;
  82        u8 data_reg;
  83        int ret;
  84        struct i2c_msg msg = {
  85                .addr = priv->i2c_address,
  86                .flags = 0,
  87                .len = sizeof(priv->config),
  88                .buf = priv->config
  89        };
  90
  91        switch (voltage) {
  92        case SEC_VOLTAGE_OFF:
  93                data_reg = LNBH29_VSEL_0;
  94                break;
  95        case SEC_VOLTAGE_13:
  96                data_reg = LNBH29_VSEL_13;
  97                break;
  98        case SEC_VOLTAGE_18:
  99                data_reg = LNBH29_VSEL_18;
 100                break;
 101        default:
 102                return -EINVAL;
 103        }
 104        priv->config[1] &= ~LNBH29_VSEL_MASK;
 105        priv->config[1] |= data_reg;
 106
 107        ret = i2c_transfer(priv->i2c, &msg, 1);
 108        if (ret >= 0 && ret != 1)
 109                ret = -EIO;
 110        if (ret < 0) {
 111                dev_err(&priv->i2c->dev, "LNBH29 I2C transfer error (%d)\n",
 112                        ret);
 113                return ret;
 114        }
 115
 116        /* Soft-start time (Vout 0V to 18V) is Typ. 6ms. */
 117        usleep_range(6000, 20000);
 118
 119        if (voltage == SEC_VOLTAGE_OFF)
 120                return 0;
 121
 122        return lnbh29_read_vmon(priv);
 123}
 124
 125static void lnbh29_release(struct dvb_frontend *fe)
 126{
 127        lnbh29_set_voltage(fe, SEC_VOLTAGE_OFF);
 128        kfree(fe->sec_priv);
 129        fe->sec_priv = NULL;
 130}
 131
 132struct dvb_frontend *lnbh29_attach(struct dvb_frontend *fe,
 133                                   struct lnbh29_config *cfg,
 134                                   struct i2c_adapter *i2c)
 135{
 136        struct lnbh29_priv *priv;
 137
 138        priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 139        if (!priv)
 140                return NULL;
 141
 142        priv->i2c_address = (cfg->i2c_address >> 1);
 143        priv->i2c = i2c;
 144        priv->config[0] = 0x01;
 145        priv->config[1] = cfg->data_config;
 146        fe->sec_priv = priv;
 147
 148        if (lnbh29_set_voltage(fe, SEC_VOLTAGE_OFF)) {
 149                dev_err(&i2c->dev, "no LNBH29 found at I2C addr 0x%02x\n",
 150                        priv->i2c_address);
 151                kfree(priv);
 152                fe->sec_priv = NULL;
 153                return NULL;
 154        }
 155
 156        fe->ops.release_sec = lnbh29_release;
 157        fe->ops.set_voltage = lnbh29_set_voltage;
 158
 159        dev_info(&i2c->dev, "LNBH29 attached at I2C addr 0x%02x\n",
 160                 priv->i2c_address);
 161
 162        return fe;
 163}
 164EXPORT_SYMBOL(lnbh29_attach);
 165
 166MODULE_AUTHOR("Katsuhiro Suzuki <suzuki.katsuhiro@socionext.com>");
 167MODULE_DESCRIPTION("STMicroelectronics LNBH29 driver");
 168MODULE_LICENSE("GPL v2");
 169