From patchwork Fri May 15 21:48:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Almeida X-Patchwork-Id: 209793 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7B02DC433E2 for ; Fri, 15 May 2020 21:48:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A9BF2070A for ; Fri, 15 May 2020 21:48:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="fSZGatxs" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727983AbgEOVsy (ORCPT ); Fri, 15 May 2020 17:48:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47162 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726266AbgEOVsx (ORCPT ); Fri, 15 May 2020 17:48:53 -0400 Received: from mail-qt1-x841.google.com (mail-qt1-x841.google.com [IPv6:2607:f8b0:4864:20::841]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 52B7AC061A0C; Fri, 15 May 2020 14:48:53 -0700 (PDT) Received: by mail-qt1-x841.google.com with SMTP id 4so3327686qtb.4; Fri, 15 May 2020 14:48:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=jJo1hcKeIy0jwOOtOttyjeXDb5p70U+Kv4mBIT4Zv9o=; b=fSZGatxs1F5l70Jm1Dei/M8YJfxmlekHJZvwQQ3Psc5flreuvI+VNRfw08HenFS1UO qOsb//c0dB2Goog4EzmOvyBC8bXNPWdwrLz9ZKY6BkkBOtAy3xLB8rfaDQKjo7a5BaLv rGx5UUygTWHg2YHxZ6I7Ly0hsjITBRCdFtr1BTBLSOP3H7ONwcIt6gh4Dcq7q7TJvMyp lXXzWNAVJtdAj8QuZrleUnFD3aSqhot+9c+EURC6/YWxQUNwyrrDxLb4H2zRhfQlC83K 922Ltx0Qnd8winDezjlHHh2C/dj7p00U9I5Y4kAIzhLXbLi8eCXJ8tFggrQykKxTOi4H R1Lg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=jJo1hcKeIy0jwOOtOttyjeXDb5p70U+Kv4mBIT4Zv9o=; b=sBSVElEVA2TcrFiqw/zdJo5x+Ax+NsyzWXILyHhdXMGj2FW48NsMwTPdEl5PvpmccG /dLuOq9LPtBvkbjTlWcROVcjWjFRfB3Ud5idAtqS+h+Ave1Cst+p0HdDwkI6TypCrgvz o3lEdBKd8xL94uNaNI6MjrLIgcbREaZUsKbAnRlv1N7dxR83khEFojEQxmmkFXcAPSE5 h/1P9gFMe5aBoMRwR6alNLJ/O7DQ3m/7JpawPk93zbLgNZ10mU7/B5fOUtw8ORPT7hIL FB5DhVCfM/7bLvrKn9NW1Vke9ehKUpldK3VPzkANqbv5/4DHhLA3PNm/pbgBpHzd4gsn 39Qw== X-Gm-Message-State: AOAM533Mj3aSl/8lLyPzPn8UFKRXU53YessPkP8V7bt16Jc9kjRpdSsz iFEjAJzbhFQCG9GdTlOGw1w= X-Google-Smtp-Source: ABdhPJyKxFG9LOZEqdimaf+DJcz4d7KYrxHmag1d1sOmZ4K9JEdgQ0wWo2sRWqJ2jTkLaI/HlYuw7Q== X-Received: by 2002:ac8:27ed:: with SMTP id x42mr5786351qtx.231.1589579332380; Fri, 15 May 2020 14:48:52 -0700 (PDT) Received: from localhost.localdomain ([2804:18:700e:2692:8980:dd13:6be6:4050]) by smtp.gmail.com with ESMTPSA id m21sm2495019qkh.50.2020.05.15.14.48.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 15 May 2020 14:48:51 -0700 (PDT) From: "Daniel W. S. Almeida" X-Google-Original-From: Daniel W. S. Almeida To: mchehab+huawei@kernel.org, sean@mess.org, kstewart@linuxfoundation.org, allison@lohutok.net, tglx@linutronix.de Cc: "Daniel W. S. Almeida" , linux-media@vger.kernel.org, skhan@linuxfoundation.org, linux-kernel-mentees@lists.linuxfoundation.org, linux-kernel@vger.kernel.org Subject: [RFC, WIP, v5 03/10] media: vidtv: implement a demodulator driver Date: Fri, 15 May 2020 18:48:08 -0300 Message-Id: <20200515214815.15514-4-dwlsalmeida@gmail.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200515214815.15514-1-dwlsalmeida@gmail.com> References: <20200515214815.15514-1-dwlsalmeida@gmail.com> MIME-Version: 1.0 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org From: "Daniel W. S. Almeida" Implement a I2C demodulator driver, simulating support for DVB-T, DVB-C and DVB-S. This demodulator will periodically check the signal quality against a table and drop the TS lock if it drops below a threshold value, regaining it in the event that the signal improves. Signed-off-by: Daniel W. S. Almeida --- drivers/media/test-drivers/vidtv/Makefile | 2 +- .../media/test-drivers/vidtv/vidtv_demod.c | 448 ++++++++++++++++++ .../media/test-drivers/vidtv/vidtv_demod.h | 42 ++ 3 files changed, 491 insertions(+), 1 deletion(-) create mode 100644 drivers/media/test-drivers/vidtv/vidtv_demod.c create mode 100644 drivers/media/test-drivers/vidtv/vidtv_demod.h diff --git a/drivers/media/test-drivers/vidtv/Makefile b/drivers/media/test-drivers/vidtv/Makefile index e625810a82603..36ba00ddc0d1e 100644 --- a/drivers/media/test-drivers/vidtv/Makefile +++ b/drivers/media/test-drivers/vidtv/Makefile @@ -1,3 +1,3 @@ # SPDX-License-Identifier: GPL-2.0 -obj-$(CONFIG_DVB_VIDTV) += vidtv_tuner.o +obj-$(CONFIG_DVB_VIDTV) += vidtv_tuner.o vidtv_demod.o diff --git a/drivers/media/test-drivers/vidtv/vidtv_demod.c b/drivers/media/test-drivers/vidtv/vidtv_demod.c new file mode 100644 index 0000000000000..2d5270e71a909 --- /dev/null +++ b/drivers/media/test-drivers/vidtv/vidtv_demod.c @@ -0,0 +1,448 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * 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. + * + * Written by Daniel W. S. Almeida + * Based on the example driver written by Emard + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "vidtv_demod.h" + +MODULE_DESCRIPTION("Virtual DVB Demodulator Driver"); +MODULE_AUTHOR("Daniel W. S. Almeida"); +MODULE_LICENSE("GPL"); + +#define POLL_THRD_TIME 2000 /* msecs */ + +static struct vidtv_demod_cnr_to_qual_s vidtv_demod_c_cnr_2_qual[] = { + /* from libdvbv5 source code, in milli db */ + { QAM_256, FEC_NONE, 34000, 38000}, + { QAM_64, FEC_NONE, 30000, 34000}, +}; + +static struct vidtv_demod_cnr_to_qual_s vidtv_demod_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 struct vidtv_demod_cnr_to_qual_s vidtv_demod_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 struct vidtv_demod_cnr_to_qual_s vidtv_demod_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}, +}; + +static struct vidtv_demod_cnr_to_qual_s +*vidtv_match_cnr_s(struct dvb_frontend *fe) +{ + struct dtv_frontend_properties *c; + struct vidtv_demod_cnr_to_qual_s *cnr2qual = NULL; + u32 array_size = 0; + u32 i; + + c = &fe->dtv_property_cache; + + switch (c->delivery_system) { + case SYS_DVBT: + case SYS_DVBT2: + cnr2qual = vidtv_demod_t_cnr_2_qual; + array_size = ARRAY_SIZE(vidtv_demod_t_cnr_2_qual); + break; + + case SYS_DVBS: + cnr2qual = vidtv_demod_s_cnr_2_qual; + array_size = ARRAY_SIZE(vidtv_demod_s_cnr_2_qual); + break; + + case SYS_DVBS2: + cnr2qual = vidtv_demod_s2_cnr_2_qual; + array_size = ARRAY_SIZE(vidtv_demod_s2_cnr_2_qual); + break; + + case SYS_DVBC_ANNEX_A: + cnr2qual = vidtv_demod_c_cnr_2_qual; + array_size = ARRAY_SIZE(vidtv_demod_c_cnr_2_qual); + break; + + default: + pr_warn_ratelimited("%s: unsupported delivery system: %u\n", + __func__, + c->delivery_system); + break; + } + + for (i = 0; i <= array_size; i++) + if (cnr2qual[i].modulation == c->modulation && + cnr2qual[i].fec == c->fec_inner) + return &cnr2qual[i]; + + return NULL; /* not found */ +} + +static void vidtv_demod_poll_snr_handler(struct work_struct *work) +{ + /* + * periodically check the signal quality and eventually + * lose the TS lock if it dips too low + */ + struct vidtv_demod_state *state; + struct dtv_frontend_properties *c; + struct vidtv_demod_cnr_to_qual_s *cnr2qual = NULL; + struct vidtv_demod_config *config; + u16 snr = 0; + + state = container_of(work, struct vidtv_demod_state, poll_snr.work); + c = &state->frontend.dtv_property_cache; + config = &state->config; + + if (!state->frontend.ops.tuner_ops.get_rf_strength) + return; + + state->frontend.ops.tuner_ops.get_rf_strength(&state->frontend, &snr); + + cnr2qual = vidtv_match_cnr_s(&state->frontend); + if (!cnr2qual) + return; + + if (snr < cnr2qual->cnr_ok) { + /* eventually lose the TS lock */ + if (prandom_u32_max(100) < config->drop_tslock_prob_on_low_snr) + state->status = 0; + } else { + /* recover if the signal improves */ + if (prandom_u32_max(100) < + config->recover_tslock_prob_on_good_snr) + state->status = FE_HAS_SIGNAL | + FE_HAS_CARRIER | + FE_HAS_VITERBI | + FE_HAS_SYNC | + FE_HAS_LOCK; + } + + schedule_delayed_work(&state->poll_snr, + msecs_to_jiffies(POLL_THRD_TIME)); +} + +static int vidtv_demod_read_status(struct dvb_frontend *fe, + enum fe_status *status) +{ + struct vidtv_demod_state *state = fe->demodulator_priv; + + *status = state->status; + + return 0; +} + +static int vidtv_demod_read_ber(struct dvb_frontend *fe, u32 *ber) +{ + *ber = 0; + return 0; +} + +static int vidtv_demod_read_signal_strength(struct dvb_frontend *fe, + u16 *strength) +{ + *strength = 0; + return 0; +} + +static int vidtv_demod_read_snr(struct dvb_frontend *fe, u16 *snr) +{ + *snr = 0; + return 0; +} + +static int vidtv_demod_read_ucblocks(struct dvb_frontend *fe, u32 *ucblocks) +{ + *ucblocks = 0; + return 0; +} + +/* + * NOTE: + * This is implemented here just to be used as an example for real + * demod drivers. + * + * Should only be implemented if it actually reads something from the hardware. + * Also, it should check for the locks, in order to avoid report wrong data + * to userspace. + */ +static int vidtv_demod_get_frontend(struct dvb_frontend *fe, + struct dtv_frontend_properties *p) +{ + return 0; +} + +static int vidtv_demod_set_frontend(struct dvb_frontend *fe) +{ + struct vidtv_demod_state *state = fe->demodulator_priv; + struct vidtv_demod_cnr_to_qual_s *cnr2qual = NULL; + u32 tuner_status = 0; + + if (fe->ops.tuner_ops.set_params) { + fe->ops.tuner_ops.set_params(fe); + + /* store the CNR returned by the tuner */ + fe->ops.tuner_ops.get_rf_strength(fe, &state->tuner_cnr); + + fe->ops.tuner_ops.get_status(fe, &tuner_status); + state->status = (state->tuner_cnr > 0) ? FE_HAS_SIGNAL | + FE_HAS_CARRIER | + FE_HAS_VITERBI | + FE_HAS_SYNC | + FE_HAS_LOCK : + 0; + cnr2qual = vidtv_match_cnr_s(fe); + + /* signal isn't good: might lose the lock eventually */ + if (tuner_status == TUNER_STATUS_LOCKED && + state->tuner_cnr < cnr2qual->cnr_good) { + schedule_delayed_work(&state->poll_snr, + msecs_to_jiffies(POLL_THRD_TIME)); + + state->poll_snr_thread_running = true; + } + + if (fe->ops.i2c_gate_ctrl) + fe->ops.i2c_gate_ctrl(fe, 0); + } + + return 0; +} + +static int vidtv_demod_sleep(struct dvb_frontend *fe) +{ + struct vidtv_demod_state *state = fe->demodulator_priv; + + if (state->poll_snr_thread_running) { + cancel_delayed_work_sync(&state->poll_snr); + state->poll_snr_thread_running = false; + state->poll_snr_thread_restart = true; + } + return 0; +} + +static int vidtv_demod_init(struct dvb_frontend *fe) +{ + struct vidtv_demod_state *state = fe->demodulator_priv; + u32 tuner_status = 0; + + if (state->cold_start) + INIT_DELAYED_WORK(&state->poll_snr, + &vidtv_demod_poll_snr_handler); + + /* + * At resume, start the snr poll thread only if it was suspended with + * the thread running. Extra care should be taken here, as some tuner + * status change might happen at resume time (for example, due to an + * ioctl syscall to set_frontend, or due to a release syscall). + */ + fe->ops.tuner_ops.get_status(fe, &tuner_status); + + if (tuner_status == TUNER_STATUS_LOCKED && + state->poll_snr_thread_restart) { + schedule_delayed_work(&state->poll_snr, + msecs_to_jiffies(POLL_THRD_TIME)); + + state->poll_snr_thread_restart = false; + } + + state->cold_start = false; + return 0; +} + +/* + * NOTE: + * This is implemented here just to be used as an example for real + * demod drivers. + * + * Should only be implemented if the demod has support for DVB-S or DVB-S2 + */ +static int vidtv_demod_set_tone(struct dvb_frontend *fe, + enum fe_sec_tone_mode tone) +{ + return 0; +} + +/* + * NOTE: + * This is implemented here just to be used as an example for real + * demod drivers. + * + * Should only be implemented if the demod has support for DVB-S or DVB-S2 + */ +static int vidtv_demod_set_voltage(struct dvb_frontend *fe, + enum fe_sec_voltage voltage) +{ + return 0; +} + +static void vidtv_demod_release(struct dvb_frontend *fe) +{ + struct vidtv_demod_state *state = fe->demodulator_priv; + + if (state->poll_snr_thread_running) + cancel_delayed_work_sync(&state->poll_snr); + + kfree(state); +} + +static const struct dvb_frontend_ops vidtv_demod_ops = { + .delsys = { + SYS_DVBT, + SYS_DVBT2, + SYS_DVBC_ANNEX_A, + SYS_DVBS, + SYS_DVBS2, + }, + + .info = { + .name = "Dummy demod for DVB-T/T2/C/S/S2", + .frequency_min_hz = 51 * MHz, + .frequency_max_hz = 2150 * MHz, + .frequency_stepsize_hz = 62500, + .frequency_tolerance_hz = 29500 * kHz, + .symbol_rate_min = 1000000, + .symbol_rate_max = 45000000, + + .caps = FE_CAN_FEC_1_2 | + FE_CAN_FEC_2_3 | + FE_CAN_FEC_3_4 | + FE_CAN_FEC_4_5 | + FE_CAN_FEC_5_6 | + FE_CAN_FEC_6_7 | + FE_CAN_FEC_7_8 | + FE_CAN_FEC_8_9 | + FE_CAN_FEC_AUTO | + FE_CAN_QAM_16 | + FE_CAN_QAM_64 | + FE_CAN_QAM_32 | + FE_CAN_QAM_128 | + FE_CAN_QAM_256 | + FE_CAN_QAM_AUTO | + FE_CAN_QPSK | + FE_CAN_FEC_AUTO | + FE_CAN_INVERSION_AUTO | + FE_CAN_TRANSMISSION_MODE_AUTO | + FE_CAN_GUARD_INTERVAL_AUTO | + FE_CAN_HIERARCHY_AUTO, + }, + + .release = vidtv_demod_release, + + .init = vidtv_demod_init, + .sleep = vidtv_demod_sleep, + + .set_frontend = vidtv_demod_set_frontend, + .get_frontend = vidtv_demod_get_frontend, + + .read_status = vidtv_demod_read_status, + .read_ber = vidtv_demod_read_ber, + .read_signal_strength = vidtv_demod_read_signal_strength, + .read_snr = vidtv_demod_read_snr, + .read_ucblocks = vidtv_demod_read_ucblocks, + + /* For DVB-S/S2 */ + .set_voltage = vidtv_demod_set_voltage, + .set_tone = vidtv_demod_set_tone, +}; + +static const struct i2c_device_id vidtv_demod_i2c_id_table[] = { + {"vidtv_demod", 0}, + {} +}; +MODULE_DEVICE_TABLE(i2c, vidtv_demod_i2c_id_table); + +static int vidtv_demod_i2c_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct vidtv_demod_config *config = client->dev.platform_data; + struct vidtv_demod_state *state; + + /* allocate memory for the internal state */ + state = kzalloc(sizeof(*state), GFP_KERNEL); + if (!state) + return -ENOMEM; + + /* create dvb_frontend */ + memcpy(&state->frontend.ops, + &vidtv_demod_ops, + sizeof(struct dvb_frontend_ops)); + + state->frontend.demodulator_priv = state; + /* return the pointer to the bridge driver */ + *config->frontend = &state->frontend; + i2c_set_clientdata(client, state); + + return 0; +} + +static int vidtv_demod_i2c_remove(struct i2c_client *client) +{ + struct vidtv_demod_state *state = i2c_get_clientdata(client); + + memset(&state->frontend.ops, 0, sizeof(struct dvb_frontend_ops)); + state->frontend.demodulator_priv = NULL; + kfree(state); + + return 0; +} + +static struct i2c_driver vidtv_demod_i2c_driver = { + .driver = { + .name = "vidtv_demod", + .suppress_bind_attrs = true, + }, + .probe = vidtv_demod_i2c_probe, + .remove = vidtv_demod_i2c_remove, + .id_table = vidtv_demod_i2c_id_table, +}; + +module_i2c_driver(vidtv_demod_i2c_driver); diff --git a/drivers/media/test-drivers/vidtv/vidtv_demod.h b/drivers/media/test-drivers/vidtv/vidtv_demod.h new file mode 100644 index 0000000000000..57d810f7a4462 --- /dev/null +++ b/drivers/media/test-drivers/vidtv/vidtv_demod.h @@ -0,0 +1,42 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * The Virtual DTV 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. + * + * Written by Daniel W. S. Almeida + * Based on the example driver written by Emard + */ + +#ifndef VIDTV_DEMOD_H +#define VIDTV_DEMOD_H + +#include +#include + +struct vidtv_demod_cnr_to_qual_s { + /* attempt to use the same values as libdvbv5 */ + u32 modulation; + u32 fec; + u32 cnr_ok, cnr_good; +}; + +struct vidtv_demod_config { + struct dvb_frontend **frontend; + /* probability of losing the lock due to low snr */ + u8 drop_tslock_prob_on_low_snr; + /* probability of recovering when the signal improves */ + u8 recover_tslock_prob_on_good_snr; +}; + +struct vidtv_demod_state { + struct dvb_frontend frontend; + struct vidtv_demod_config config; + struct delayed_work poll_snr; + enum fe_status status; + u16 tuner_cnr; + bool cold_start; + bool poll_snr_thread_running; + bool poll_snr_thread_restart; +}; +#endif // VIDTV_DEMOD_H