diff options
Diffstat (limited to 'drivers/media/test-drivers/vidtv/vidtv_tuner.c')
| -rw-r--r-- | drivers/media/test-drivers/vidtv/vidtv_tuner.c | 439 |
1 files changed, 439 insertions, 0 deletions
diff --git a/drivers/media/test-drivers/vidtv/vidtv_tuner.c b/drivers/media/test-drivers/vidtv/vidtv_tuner.c new file mode 100644 index 000000000..14b6bc902 --- /dev/null +++ b/drivers/media/test-drivers/vidtv/vidtv_tuner.c @@ -0,0 +1,439 @@ +// 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/printk.h> +#include <linux/ratelimit.h> +#include <linux/slab.h> +#include <linux/types.h> + +#include <media/dvb_frontend.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"); |