blob: 9bc49e099f6533be135aaee195ad3e426284a26b [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* The Virtual DVB test driver serves as a reference DVB driver and helps
* validate the existing APIs in the media subsystem. It can also aid
* developers working on userspace applications.
*
* The vidtv tuner should support common TV standards such as
* DVB-T/T2/S/S2, ISDB-T and ATSC when completed.
*
* Copyright (C) 2020 Daniel W. S. Almeida
*/
#include <linux/errno.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <media/dvb_frontend.h>
#include <linux/printk.h>
#include <linux/ratelimit.h>
#include "vidtv_tuner.h"
struct vidtv_tuner_cnr_to_qual_s {
/* attempt to use the same values as libdvbv5 */
u32 modulation;
u32 fec;
u32 cnr_ok;
u32 cnr_good;
};
static const struct vidtv_tuner_cnr_to_qual_s vidtv_tuner_c_cnr_2_qual[] = {
/* from libdvbv5 source code, in milli db */
{ QAM_256, FEC_NONE, 34000, 38000},
{ QAM_64, FEC_NONE, 30000, 34000},
};
static const struct vidtv_tuner_cnr_to_qual_s vidtv_tuner_s_cnr_2_qual[] = {
/* from libdvbv5 source code, in milli db */
{ QPSK, FEC_1_2, 7000, 10000},
{ QPSK, FEC_2_3, 9000, 12000},
{ QPSK, FEC_3_4, 10000, 13000},
{ QPSK, FEC_5_6, 11000, 14000},
{ QPSK, FEC_7_8, 12000, 15000},
};
static const struct vidtv_tuner_cnr_to_qual_s vidtv_tuner_s2_cnr_2_qual[] = {
/* from libdvbv5 source code, in milli db */
{ QPSK, FEC_1_2, 9000, 12000},
{ QPSK, FEC_2_3, 11000, 14000},
{ QPSK, FEC_3_4, 12000, 15000},
{ QPSK, FEC_5_6, 12000, 15000},
{ QPSK, FEC_8_9, 13000, 16000},
{ QPSK, FEC_9_10, 13500, 16500},
{ PSK_8, FEC_2_3, 14500, 17500},
{ PSK_8, FEC_3_4, 16000, 19000},
{ PSK_8, FEC_5_6, 17500, 20500},
{ PSK_8, FEC_8_9, 19000, 22000},
};
static const struct vidtv_tuner_cnr_to_qual_s vidtv_tuner_t_cnr_2_qual[] = {
/* from libdvbv5 source code, in milli db*/
{ QPSK, FEC_1_2, 4100, 5900},
{ QPSK, FEC_2_3, 6100, 9600},
{ QPSK, FEC_3_4, 7200, 12400},
{ QPSK, FEC_5_6, 8500, 15600},
{ QPSK, FEC_7_8, 9200, 17500},
{ QAM_16, FEC_1_2, 9800, 11800},
{ QAM_16, FEC_2_3, 12100, 15300},
{ QAM_16, FEC_3_4, 13400, 18100},
{ QAM_16, FEC_5_6, 14800, 21300},
{ QAM_16, FEC_7_8, 15700, 23600},
{ QAM_64, FEC_1_2, 14000, 16000},
{ QAM_64, FEC_2_3, 19900, 25400},
{ QAM_64, FEC_3_4, 24900, 27900},
{ QAM_64, FEC_5_6, 21300, 23300},
{ QAM_64, FEC_7_8, 22000, 24000},
};
/**
* struct vidtv_tuner_hardware_state - Simulate the tuner hardware status
* @asleep: whether the tuner is asleep, i.e whether _sleep() or _suspend() was
* called.
* @lock_status: Whether the tuner has managed to lock on the requested
* frequency.
* @if_frequency: The tuner's intermediate frequency. Hardcoded for the purposes
* of simulation.
* @tuned_frequency: The actual tuned frequency.
* @bandwidth: The actual bandwidth.
*
* This structure is meant to simulate the status of the tuner hardware, as if
* we had a physical tuner hardware.
*/
struct vidtv_tuner_hardware_state {
bool asleep;
u32 lock_status;
u32 if_frequency;
u32 tuned_frequency;
u32 bandwidth;
};
/**
* struct vidtv_tuner_dev - The tuner struct
* @fe: A pointer to the dvb_frontend structure allocated by vidtv_demod
* @hw_state: A struct to simulate the tuner's hardware state as if we had a
* physical tuner hardware.
* @config: The configuration used to start the tuner module, usually filled
* by a bridge driver. For vidtv, this is filled by vidtv_bridge before the
* tuner module is probed.
*/
struct vidtv_tuner_dev {
struct dvb_frontend *fe;
struct vidtv_tuner_hardware_state hw_state;
struct vidtv_tuner_config config;
};
static struct vidtv_tuner_dev*
vidtv_tuner_get_dev(struct dvb_frontend *fe)
{
return i2c_get_clientdata(fe->tuner_priv);
}
static int vidtv_tuner_check_frequency_shift(struct dvb_frontend *fe)
{
struct vidtv_tuner_dev *tuner_dev = vidtv_tuner_get_dev(fe);
struct dtv_frontend_properties *c = &fe->dtv_property_cache;
struct vidtv_tuner_config config = tuner_dev->config;
u32 *valid_freqs = NULL;
u32 array_sz = 0;
u32 i;
u32 shift;
switch (c->delivery_system) {
case SYS_DVBT:
case SYS_DVBT2:
valid_freqs = config.vidtv_valid_dvb_t_freqs;
array_sz = ARRAY_SIZE(config.vidtv_valid_dvb_t_freqs);
break;
case SYS_DVBS:
case SYS_DVBS2:
valid_freqs = config.vidtv_valid_dvb_s_freqs;
array_sz = ARRAY_SIZE(config.vidtv_valid_dvb_s_freqs);
break;
case SYS_DVBC_ANNEX_A:
valid_freqs = config.vidtv_valid_dvb_c_freqs;
array_sz = ARRAY_SIZE(config.vidtv_valid_dvb_c_freqs);
break;
default:
dev_warn(fe->dvb->device,
"%s: unsupported delivery system: %u\n",
__func__,
c->delivery_system);
return -EINVAL;
}
for (i = 0; i < array_sz; i++) {
if (!valid_freqs[i])
break;
shift = abs(c->frequency - valid_freqs[i]);
if (!shift)
return 0;
/*
* This will provide a value from 0 to 100 that would
* indicate how far is the tuned frequency from the
* right one.
*/
if (shift < config.max_frequency_shift_hz)
return shift * 100 / config.max_frequency_shift_hz;
}
return -EINVAL;
}
static int
vidtv_tuner_get_signal_strength(struct dvb_frontend *fe, u16 *strength)
{
struct dtv_frontend_properties *c = &fe->dtv_property_cache;
struct vidtv_tuner_dev *tuner_dev = vidtv_tuner_get_dev(fe);
const struct vidtv_tuner_cnr_to_qual_s *cnr2qual = NULL;
struct device *dev = fe->dvb->device;
u32 array_size = 0;
s32 shift;
u32 i;
shift = vidtv_tuner_check_frequency_shift(fe);
if (shift < 0) {
tuner_dev->hw_state.lock_status = 0;
*strength = 0;
return 0;
}
switch (c->delivery_system) {
case SYS_DVBT:
case SYS_DVBT2:
cnr2qual = vidtv_tuner_t_cnr_2_qual;
array_size = ARRAY_SIZE(vidtv_tuner_t_cnr_2_qual);
break;
case SYS_DVBS:
cnr2qual = vidtv_tuner_s_cnr_2_qual;
array_size = ARRAY_SIZE(vidtv_tuner_s_cnr_2_qual);
break;
case SYS_DVBS2:
cnr2qual = vidtv_tuner_s2_cnr_2_qual;
array_size = ARRAY_SIZE(vidtv_tuner_s2_cnr_2_qual);
break;
case SYS_DVBC_ANNEX_A:
cnr2qual = vidtv_tuner_c_cnr_2_qual;
array_size = ARRAY_SIZE(vidtv_tuner_c_cnr_2_qual);
break;
default:
dev_warn_ratelimited(dev,
"%s: unsupported delivery system: %u\n",
__func__,
c->delivery_system);
return -EINVAL;
}
for (i = 0; i < array_size; i++) {
if (cnr2qual[i].modulation != c->modulation ||
cnr2qual[i].fec != c->fec_inner)
continue;
if (!shift) {
*strength = cnr2qual[i].cnr_good;
return 0;
}
/*
* Channel tuned at wrong frequency. Simulate that the
* Carrier S/N ratio is not too good.
*/
*strength = cnr2qual[i].cnr_ok -
(cnr2qual[i].cnr_good - cnr2qual[i].cnr_ok);
return 0;
}
/*
* do a linear interpolation between 34dB and 10dB if we can't
* match against the table
*/
*strength = 34000 - 24000 * shift / 100;
return 0;
}
static int vidtv_tuner_init(struct dvb_frontend *fe)
{
struct vidtv_tuner_dev *tuner_dev = vidtv_tuner_get_dev(fe);
struct vidtv_tuner_config config = tuner_dev->config;
msleep_interruptible(config.mock_power_up_delay_msec);
tuner_dev->hw_state.asleep = false;
tuner_dev->hw_state.if_frequency = 5000;
return 0;
}
static int vidtv_tuner_sleep(struct dvb_frontend *fe)
{
struct vidtv_tuner_dev *tuner_dev = vidtv_tuner_get_dev(fe);
tuner_dev->hw_state.asleep = true;
return 0;
}
static int vidtv_tuner_suspend(struct dvb_frontend *fe)
{
struct vidtv_tuner_dev *tuner_dev = vidtv_tuner_get_dev(fe);
tuner_dev->hw_state.asleep = true;
return 0;
}
static int vidtv_tuner_resume(struct dvb_frontend *fe)
{
struct vidtv_tuner_dev *tuner_dev = vidtv_tuner_get_dev(fe);
tuner_dev->hw_state.asleep = false;
return 0;
}
static int vidtv_tuner_set_params(struct dvb_frontend *fe)
{
struct vidtv_tuner_dev *tuner_dev = vidtv_tuner_get_dev(fe);
struct vidtv_tuner_config config = tuner_dev->config;
struct dtv_frontend_properties *c = &fe->dtv_property_cache;
s32 shift;
u32 min_freq = fe->ops.tuner_ops.info.frequency_min_hz;
u32 max_freq = fe->ops.tuner_ops.info.frequency_max_hz;
u32 min_bw = fe->ops.tuner_ops.info.bandwidth_min;
u32 max_bw = fe->ops.tuner_ops.info.bandwidth_max;
if (c->frequency < min_freq || c->frequency > max_freq ||
c->bandwidth_hz < min_bw || c->bandwidth_hz > max_bw) {
tuner_dev->hw_state.lock_status = 0;
return -EINVAL;
}
tuner_dev->hw_state.tuned_frequency = c->frequency;
tuner_dev->hw_state.bandwidth = c->bandwidth_hz;
tuner_dev->hw_state.lock_status = TUNER_STATUS_LOCKED;
msleep_interruptible(config.mock_tune_delay_msec);
shift = vidtv_tuner_check_frequency_shift(fe);
if (shift < 0) {
tuner_dev->hw_state.lock_status = 0;
return shift;
}
return 0;
}
static int vidtv_tuner_set_config(struct dvb_frontend *fe,
void *priv_cfg)
{
struct vidtv_tuner_dev *tuner_dev = vidtv_tuner_get_dev(fe);
memcpy(&tuner_dev->config, priv_cfg, sizeof(tuner_dev->config));
return 0;
}
static int vidtv_tuner_get_frequency(struct dvb_frontend *fe,
u32 *frequency)
{
struct vidtv_tuner_dev *tuner_dev = vidtv_tuner_get_dev(fe);
*frequency = tuner_dev->hw_state.tuned_frequency;
return 0;
}
static int vidtv_tuner_get_bandwidth(struct dvb_frontend *fe,
u32 *bandwidth)
{
struct vidtv_tuner_dev *tuner_dev = vidtv_tuner_get_dev(fe);
*bandwidth = tuner_dev->hw_state.bandwidth;
return 0;
}
static int vidtv_tuner_get_if_frequency(struct dvb_frontend *fe,
u32 *frequency)
{
struct vidtv_tuner_dev *tuner_dev = vidtv_tuner_get_dev(fe);
*frequency = tuner_dev->hw_state.if_frequency;
return 0;
}
static int vidtv_tuner_get_status(struct dvb_frontend *fe, u32 *status)
{
struct vidtv_tuner_dev *tuner_dev = vidtv_tuner_get_dev(fe);
*status = tuner_dev->hw_state.lock_status;
return 0;
}
static const struct dvb_tuner_ops vidtv_tuner_ops = {
.init = vidtv_tuner_init,
.sleep = vidtv_tuner_sleep,
.suspend = vidtv_tuner_suspend,
.resume = vidtv_tuner_resume,
.set_params = vidtv_tuner_set_params,
.set_config = vidtv_tuner_set_config,
.get_bandwidth = vidtv_tuner_get_bandwidth,
.get_frequency = vidtv_tuner_get_frequency,
.get_if_frequency = vidtv_tuner_get_if_frequency,
.get_status = vidtv_tuner_get_status,
.get_rf_strength = vidtv_tuner_get_signal_strength
};
static const struct i2c_device_id vidtv_tuner_i2c_id_table[] = {
{"dvb_vidtv_tuner", 0},
{}
};
MODULE_DEVICE_TABLE(i2c, vidtv_tuner_i2c_id_table);
static int vidtv_tuner_i2c_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct vidtv_tuner_config *config = client->dev.platform_data;
struct dvb_frontend *fe = config->fe;
struct vidtv_tuner_dev *tuner_dev = NULL;
tuner_dev = kzalloc(sizeof(*tuner_dev), GFP_KERNEL);
if (!tuner_dev)
return -ENOMEM;
tuner_dev->fe = config->fe;
i2c_set_clientdata(client, tuner_dev);
memcpy(&fe->ops.tuner_ops,
&vidtv_tuner_ops,
sizeof(struct dvb_tuner_ops));
memcpy(&tuner_dev->config, config, sizeof(tuner_dev->config));
fe->tuner_priv = client;
return 0;
}
static int vidtv_tuner_i2c_remove(struct i2c_client *client)
{
struct vidtv_tuner_dev *tuner_dev = i2c_get_clientdata(client);
kfree(tuner_dev);
return 0;
}
static struct i2c_driver vidtv_tuner_i2c_driver = {
.driver = {
.name = "dvb_vidtv_tuner",
.suppress_bind_attrs = true,
},
.probe = vidtv_tuner_i2c_probe,
.remove = vidtv_tuner_i2c_remove,
.id_table = vidtv_tuner_i2c_id_table,
};
module_i2c_driver(vidtv_tuner_i2c_driver);
MODULE_DESCRIPTION("Virtual DVB Tuner");
MODULE_AUTHOR("Daniel W. S. Almeida");
MODULE_LICENSE("GPL");