--- /dev/null
+// 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
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ":%s, %d: " fmt, __func__, __LINE__
+
+#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 s32 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:
+ pr_warn("%s: unsupported delivery system: %u\n",
+ __func__,
+ c->delivery_system);
+
+ return -EINVAL;
+ }
+
+ for (i = 0; i < array_sz; i++) {
+ 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;
+ const struct vidtv_tuner_cnr_to_qual_s *cnr2qual = NULL;
+ u32 array_size = 0;
+ s32 shift;
+ u32 i;
+
+ shift = vidtv_tuner_check_frequency_shift(fe);
+
+ 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:
+ pr_warn_ratelimited("%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;
+ }
+ if (shift < 0) { /* Channel not tuned */
+ *strength = 0;
+ 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 = 34 - 24 * 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;
+
+ 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);
+ 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));
+
+ 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);
+ struct dvb_frontend *fe = tuner_dev->fe;
+
+ memset(&fe->ops.tuner_ops, 0, sizeof(struct dvb_tuner_ops));
+ fe->tuner_priv = NULL;
+ 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");
projects / users / hch / xfs.git / commitdiff