diff options
Diffstat (limited to 'drivers/media/i2c/tda9840.c')
| -rw-r--r-- | drivers/media/i2c/tda9840.c | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/drivers/media/i2c/tda9840.c b/drivers/media/i2c/tda9840.c new file mode 100644 index 0000000000..1911ef2126 --- /dev/null +++ b/drivers/media/i2c/tda9840.c @@ -0,0 +1,199 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + /* + tda9840 - i2c-driver for the tda9840 by SGS Thomson + + Copyright (C) 1998-2003 Michael Hunold <michael@mihu.de> + Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl> + + The tda9840 is a stereo/dual sound processor with digital + identification. It can be found at address 0x84 on the i2c-bus. + + For detailed information download the specifications directly + from SGS Thomson at http://www.st.com + + */ + + +#include <linux/module.h> +#include <linux/ioctl.h> +#include <linux/slab.h> +#include <linux/i2c.h> +#include <media/v4l2-device.h> + +MODULE_AUTHOR("Michael Hunold <michael@mihu.de>"); +MODULE_DESCRIPTION("tda9840 driver"); +MODULE_LICENSE("GPL"); + +static int debug; +module_param(debug, int, 0644); + +MODULE_PARM_DESC(debug, "Debug level (0-1)"); + +#define SWITCH 0x00 +#define LEVEL_ADJUST 0x02 +#define STEREO_ADJUST 0x03 +#define TEST 0x04 + +#define TDA9840_SET_MUTE 0x00 +#define TDA9840_SET_MONO 0x10 +#define TDA9840_SET_STEREO 0x2a +#define TDA9840_SET_LANG1 0x12 +#define TDA9840_SET_LANG2 0x1e +#define TDA9840_SET_BOTH 0x1a +#define TDA9840_SET_BOTH_R 0x16 +#define TDA9840_SET_EXTERNAL 0x7a + + +static void tda9840_write(struct v4l2_subdev *sd, u8 reg, u8 val) +{ + struct i2c_client *client = v4l2_get_subdevdata(sd); + + if (i2c_smbus_write_byte_data(client, reg, val)) + v4l2_dbg(1, debug, sd, "error writing %02x to %02x\n", + val, reg); +} + +static int tda9840_status(struct v4l2_subdev *sd) +{ + struct i2c_client *client = v4l2_get_subdevdata(sd); + int rc; + u8 byte; + + rc = i2c_master_recv(client, &byte, 1); + if (rc != 1) { + v4l2_dbg(1, debug, sd, + "i2c_master_recv() failed\n"); + if (rc < 0) + return rc; + return -EIO; + } + + if (byte & 0x80) { + v4l2_dbg(1, debug, sd, + "TDA9840_DETECT: register contents invalid\n"); + return -EINVAL; + } + + v4l2_dbg(1, debug, sd, "TDA9840_DETECT: byte: 0x%02x\n", byte); + return byte & 0x60; +} + +static int tda9840_s_tuner(struct v4l2_subdev *sd, const struct v4l2_tuner *t) +{ + int stat = tda9840_status(sd); + int byte; + + if (t->index) + return -EINVAL; + + stat = stat < 0 ? 0 : stat; + if (stat == 0 || stat == 0x60) /* mono input */ + byte = TDA9840_SET_MONO; + else if (stat == 0x40) /* stereo input */ + byte = (t->audmode == V4L2_TUNER_MODE_MONO) ? + TDA9840_SET_MONO : TDA9840_SET_STEREO; + else { /* bilingual */ + switch (t->audmode) { + case V4L2_TUNER_MODE_LANG1_LANG2: + byte = TDA9840_SET_BOTH; + break; + case V4L2_TUNER_MODE_LANG2: + byte = TDA9840_SET_LANG2; + break; + default: + byte = TDA9840_SET_LANG1; + break; + } + } + v4l2_dbg(1, debug, sd, "TDA9840_SWITCH: 0x%02x\n", byte); + tda9840_write(sd, SWITCH, byte); + return 0; +} + +static int tda9840_g_tuner(struct v4l2_subdev *sd, struct v4l2_tuner *t) +{ + int stat = tda9840_status(sd); + + if (stat < 0) + return stat; + + t->rxsubchans = V4L2_TUNER_SUB_MONO; + + switch (stat & 0x60) { + case 0x00: + t->rxsubchans = V4L2_TUNER_SUB_MONO; + break; + case 0x20: + t->rxsubchans = V4L2_TUNER_SUB_LANG1 | V4L2_TUNER_SUB_LANG2; + break; + case 0x40: + t->rxsubchans = V4L2_TUNER_SUB_STEREO | V4L2_TUNER_SUB_MONO; + break; + default: /* Incorrect detect */ + t->rxsubchans = V4L2_TUNER_MODE_MONO; + break; + } + return 0; +} + +/* ----------------------------------------------------------------------- */ + +static const struct v4l2_subdev_tuner_ops tda9840_tuner_ops = { + .s_tuner = tda9840_s_tuner, + .g_tuner = tda9840_g_tuner, +}; + +static const struct v4l2_subdev_ops tda9840_ops = { + .tuner = &tda9840_tuner_ops, +}; + +/* ----------------------------------------------------------------------- */ + +static int tda9840_probe(struct i2c_client *client) +{ + struct v4l2_subdev *sd; + + /* let's see whether this adapter can support what we need */ + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_READ_BYTE_DATA | + I2C_FUNC_SMBUS_WRITE_BYTE_DATA)) + return -EIO; + + v4l_info(client, "chip found @ 0x%x (%s)\n", + client->addr << 1, client->adapter->name); + + sd = devm_kzalloc(&client->dev, sizeof(*sd), GFP_KERNEL); + if (sd == NULL) + return -ENOMEM; + v4l2_i2c_subdev_init(sd, client, &tda9840_ops); + + /* set initial values for level & stereo - adjustment, mode */ + tda9840_write(sd, LEVEL_ADJUST, 0); + tda9840_write(sd, STEREO_ADJUST, 0); + tda9840_write(sd, SWITCH, TDA9840_SET_STEREO); + return 0; +} + +static void tda9840_remove(struct i2c_client *client) +{ + struct v4l2_subdev *sd = i2c_get_clientdata(client); + + v4l2_device_unregister_subdev(sd); +} + +static const struct i2c_device_id tda9840_id[] = { + { "tda9840", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, tda9840_id); + +static struct i2c_driver tda9840_driver = { + .driver = { + .name = "tda9840", + }, + .probe = tda9840_probe, + .remove = tda9840_remove, + .id_table = tda9840_id, +}; + +module_i2c_driver(tda9840_driver); |