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1// SPDX-License-Identifier: GPL-2.0-or-later2 /*3 tda9840 - i2c-driver for the tda9840 by SGS Thomson4 5 Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de>6 Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>7 8 The tda9840 is a stereo/dual sound processor with digital9 identification. It can be found at address 0x84 on the i2c-bus.10 11 For detailed information download the specifications directly12 from SGS Thomson at http://www.st.com13 14 */15 16 17#include <linux/module.h>18#include <linux/ioctl.h>19#include <linux/slab.h>20#include <linux/i2c.h>21#include <media/v4l2-device.h>22 23MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");24MODULE_DESCRIPTION("tda9840 driver");25MODULE_LICENSE("GPL");26 27static int debug;28module_param(debug, int, 0644);29 30MODULE_PARM_DESC(debug, "Debug level (0-1)");31 32#define SWITCH 0x0033#define LEVEL_ADJUST 0x0234#define STEREO_ADJUST 0x0335#define TEST 0x0436 37#define TDA9840_SET_MUTE 0x0038#define TDA9840_SET_MONO 0x1039#define TDA9840_SET_STEREO 0x2a40#define TDA9840_SET_LANG1 0x1241#define TDA9840_SET_LANG2 0x1e42#define TDA9840_SET_BOTH 0x1a43#define TDA9840_SET_BOTH_R 0x1644#define TDA9840_SET_EXTERNAL 0x7a45 46 47static void tda9840_write(struct v4l2_subdev *sd, u8 reg, u8 val)48{49 struct i2c_client *client = v4l2_get_subdevdata(sd);50 51 if (i2c_smbus_write_byte_data(client, reg, val))52 v4l2_dbg(1, debug, sd, "error writing %02x to %02x\n",53 val, reg);54}55 56static int tda9840_status(struct v4l2_subdev *sd)57{58 struct i2c_client *client = v4l2_get_subdevdata(sd);59 int rc;60 u8 byte;61 62 rc = i2c_master_recv(client, &byte, 1);63 if (rc != 1) {64 v4l2_dbg(1, debug, sd,65 "i2c_master_recv() failed\n");66 if (rc < 0)67 return rc;68 return -EIO;69 }70 71 if (byte & 0x80) {72 v4l2_dbg(1, debug, sd,73 "TDA9840_DETECT: register contents invalid\n");74 return -EINVAL;75 }76 77 v4l2_dbg(1, debug, sd, "TDA9840_DETECT: byte: 0x%02x\n", byte);78 return byte & 0x60;79}80 81static int tda9840_s_tuner(struct v4l2_subdev *sd, const struct v4l2_tuner *t)82{83 int stat = tda9840_status(sd);84 int byte;85 86 if (t->index)87 return -EINVAL;88 89 stat = stat < 0 ? 0 : stat;90 if (stat == 0 || stat == 0x60) /* mono input */91 byte = TDA9840_SET_MONO;92 else if (stat == 0x40) /* stereo input */93 byte = (t->audmode == V4L2_TUNER_MODE_MONO) ?94 TDA9840_SET_MONO : TDA9840_SET_STEREO;95 else { /* bilingual */96 switch (t->audmode) {97 case V4L2_TUNER_MODE_LANG1_LANG2:98 byte = TDA9840_SET_BOTH;99 break;100 case V4L2_TUNER_MODE_LANG2:101 byte = TDA9840_SET_LANG2;102 break;103 default:104 byte = TDA9840_SET_LANG1;105 break;106 }107 }108 v4l2_dbg(1, debug, sd, "TDA9840_SWITCH: 0x%02x\n", byte);109 tda9840_write(sd, SWITCH, byte);110 return 0;111}112 113static int tda9840_g_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *t)114{115 int stat = tda9840_status(sd);116 117 if (stat < 0)118 return stat;119 120 t->rxsubchans = V4L2_TUNER_SUB_MONO;121 122 switch (stat & 0x60) {123 case 0x00:124 t->rxsubchans = V4L2_TUNER_SUB_MONO;125 break;126 case 0x20:127 t->rxsubchans = V4L2_TUNER_SUB_LANG1 | V4L2_TUNER_SUB_LANG2;128 break;129 case 0x40:130 t->rxsubchans = V4L2_TUNER_SUB_STEREO | V4L2_TUNER_SUB_MONO;131 break;132 default: /* Incorrect detect */133 t->rxsubchans = V4L2_TUNER_MODE_MONO;134 break;135 }136 return 0;137}138 139/* ----------------------------------------------------------------------- */140 141static const struct v4l2_subdev_tuner_ops tda9840_tuner_ops = {142 .s_tuner = tda9840_s_tuner,143 .g_tuner = tda9840_g_tuner,144};145 146static const struct v4l2_subdev_ops tda9840_ops = {147 .tuner = &tda9840_tuner_ops,148};149 150/* ----------------------------------------------------------------------- */151 152static int tda9840_probe(struct i2c_client *client)153{154 struct v4l2_subdev *sd;155 156 /* let's see whether this adapter can support what we need */157 if (!i2c_check_functionality(client->adapter,158 I2C_FUNC_SMBUS_READ_BYTE_DATA |159 I2C_FUNC_SMBUS_WRITE_BYTE_DATA))160 return -EIO;161 162 v4l_info(client, "chip found @ 0x%x (%s)\n",163 client->addr << 1, client->adapter->name);164 165 sd = devm_kzalloc(&client->dev, sizeof(*sd), GFP_KERNEL);166 if (sd == NULL)167 return -ENOMEM;168 v4l2_i2c_subdev_init(sd, client, &tda9840_ops);169 170 /* set initial values for level & stereo - adjustment, mode */171 tda9840_write(sd, LEVEL_ADJUST, 0);172 tda9840_write(sd, STEREO_ADJUST, 0);173 tda9840_write(sd, SWITCH, TDA9840_SET_STEREO);174 return 0;175}176 177static void tda9840_remove(struct i2c_client *client)178{179 struct v4l2_subdev *sd = i2c_get_clientdata(client);180 181 v4l2_device_unregister_subdev(sd);182}183 184static const struct i2c_device_id tda9840_id[] = {185 { "tda9840" },186 { }187};188MODULE_DEVICE_TABLE(i2c, tda9840_id);189 190static struct i2c_driver tda9840_driver = {191 .driver = {192 .name = "tda9840",193 },194 .probe = tda9840_probe,195 .remove = tda9840_remove,196 .id_table = tda9840_id,197};198 199module_i2c_driver(tda9840_driver);200