From patchwork Thu Jun 11 11:57:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Gonzalez X-Patchwork-Id: 64434 Received: from vger.kernel.org ([23.128.96.18]) by www.linuxtv.org with esmtp (Exim 4.92) (envelope-from ) id 1jjLll-008Sbg-1j; Thu, 11 Jun 2020 11:53:18 +0000 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727775AbgFKL5Q (ORCPT + 1 other); Thu, 11 Jun 2020 07:57:16 -0400 Received: from ns.iliad.fr ([212.27.33.1]:46058 "EHLO ns.iliad.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726407AbgFKL5Q (ORCPT ); Thu, 11 Jun 2020 07:57:16 -0400 Received: from ns.iliad.fr (localhost [127.0.0.1]) by ns.iliad.fr (Postfix) with ESMTP id 0761B21869; Thu, 11 Jun 2020 13:57:14 +0200 (CEST) Received: from [192.168.108.51] (freebox.vlq16.iliad.fr [213.36.7.13]) by ns.iliad.fr (Postfix) with ESMTP id E2EC021860; Thu, 11 Jun 2020 13:57:13 +0200 (CEST) To: Mauro Carvalho Chehab , Sean Young , Brad Love Cc: linux-media , LKML , Antti Palosaari , Jan Pieter van Woerkom From: Marc Gonzalez Subject: [RFC PATCH][DO NOT COMMIT] media: dvb_frontend: Support concurrent DVB-T/DVB-T2 scan Message-ID: <4c32558d-3be7-9a57-b655-65c744c1e532@free.fr> Date: Thu, 11 Jun 2020 13:57:13 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 Content-Language: en-US X-Virus-Scanned: ClamAV using ClamSMTP ; ns.iliad.fr ; Thu Jun 11 13:57:14 2020 +0200 (CEST) Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-LSpam-Score: -2.4 (--) X-LSpam-Report: No, score=-2.4 required=5.0 tests=BAYES_00=-1.9,FREEMAIL_FORGED_FROMDOMAIN=0.001,FREEMAIL_FROM=0.001,HEADER_FROM_DIFFERENT_DOMAINS=0.5,MAILING_LIST_MULTI=-1 autolearn=ham autolearn_force=no Some demodulators (e.g. si2168) are able to scan for DVB-T and DVB-T2 signals concurrently. Use SYS_DVBT_AUTO for this purpose. --- This is a Request For Comments from media maintainers and users :-) One issue: suppose DVB Project publishes DVB-T3 in a few years. Today's demods might handle T/T2, but they won't handle T3, while users may expect SYS_DVBT_AUTO to mean "all DVB-T standards". Therefore, perhaps the delsys name should be explicit, like SYS_DVBT_DVBT2 or SYS_DVBT_1_2. Then if/when DVB_T3 appears, we can add SYS_DVBT_1_2_3 ??? Or maybe use the FE_CAN_2G_MODULATION and hypothetical FE_CAN_3G_MODULATION Or maybe, with several standards having a v2 and possibly v3 in the future, delivery system might move to a bitmask approach? (API issues though) Reference to related implementation: https://patchwork.kernel.org/patch/10744999/ --- drivers/media/dvb-frontends/si2168.c | 2 +- include/uapi/linux/dvb/frontend.h | 3 +++ 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/media/dvb-frontends/si2168.c b/drivers/media/dvb-frontends/si2168.c index 14b93a7d3358..8578b8917955 100644 --- a/drivers/media/dvb-frontends/si2168.c +++ b/drivers/media/dvb-frontends/si2168.c @@ -624,7 +624,7 @@ static int si2168_deselect(struct i2c_mux_core *muxc, u32 chan) } static const struct dvb_frontend_ops si2168_ops = { - .delsys = {SYS_DVBT, SYS_DVBT2, SYS_DVBC_ANNEX_A}, + .delsys = {SYS_DVBT, SYS_DVBT2, SYS_DVBT_AUTO, SYS_DVBC_ANNEX_A}, .info = { .name = "Silicon Labs Si2168", .frequency_min_hz = 48 * MHz, diff --git a/include/uapi/linux/dvb/frontend.h b/include/uapi/linux/dvb/frontend.h index 4f9b4551c534..3a6348748041 100644 --- a/include/uapi/linux/dvb/frontend.h +++ b/include/uapi/linux/dvb/frontend.h @@ -600,6 +600,8 @@ enum fe_rolloff { * Terrestrial TV: DVB-T * @SYS_DVBT2: * Terrestrial TV: DVB-T2 + * @SYS_DVBT_AUTO: + * Terrestrial TV: Autodetect DVB-T gen * @SYS_ISDBT: * Terrestrial TV: ISDB-T * @SYS_ATSC: @@ -645,6 +647,7 @@ enum fe_delivery_system { SYS_DVBT2, SYS_TURBO, SYS_DVBC_ANNEX_C, + SYS_DVBT_AUTO, }; /* backward compatibility definitions for delivery systems */