From nobody Fri Feb 03 07:40:17 2023 X-Original-To: freebsd-current@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4P7SRC6Lswz2nJ1W for ; Fri, 3 Feb 2023 07:47:03 +0000 (UTC) (envelope-from manu@bidouilliste.com) Received: from mx.blih.net (mx.blih.net [212.83.155.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "mx.blih.net", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4P7SRC2dKMz4VTK for ; Fri, 3 Feb 2023 07:47:03 +0000 (UTC) (envelope-from manu@bidouilliste.com) Authentication-Results: mx1.freebsd.org; none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bidouilliste.com; s=mx; t=1675410020; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=hG50qnfyhHg7ehDIWTXmiojkvJWtlvgx2btSbH6Hrjo=; b=gVmiRtIDulLPMPvo5BpGKe238VU6J6hxgkh9f0CfNrcT7btg7SiywVUWrEiPjCIoVauvGW MLXRCIOsKTra5NSUUCdEciDEBXjYl6wu2GhO7ebuhnmmKrpkrBCyAjS5hRU6IU4KU08k1M twwP51WeajH3AZ9AESCM5b1bfeqrew0= Received: from skull.home.blih.net (lfbn-lyo-1-2174-135.w90-66.abo.wanadoo.fr [90.66.97.135]) by mx.blih.net (OpenSMTPD) with ESMTPSA id e513296c (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO); Fri, 3 Feb 2023 07:40:20 +0000 (UTC) Date: Fri, 3 Feb 2023 08:40:17 +0100 From: Emmanuel Vadot To: "Poul-Henning Kamp" Cc: "parv/FreeBSD" , freebsd-current@freebsd.org Subject: Re: Could not change brightness anymore with i915kms & acpi_video modules c 202211 Message-Id: <20230203084017.b1e8dc1f9116d8a55a1c2cfd@bidouilliste.com> In-Reply-To: <202302022058.312Kwwj8003814@critter.freebsd.dk> References: <202302022058.312Kwwj8003814@critter.freebsd.dk> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; amd64-portbld-freebsd14.0) List-Id: Discussions about the use of FreeBSD-current List-Archive: https://lists.freebsd.org/archives/freebsd-current List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-current@freebsd.org Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 4P7SRC2dKMz4VTK X-Spamd-Bar: ---- X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; TAGGED_RCPT(0.00)[freebsd]; ASN(0.00)[asn:12876, ipnet:212.83.128.0/19, country:FR] X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-ThisMailContainsUnwantedMimeParts: N On Thu, 02 Feb 2023 20:58:58 +0000 "Poul-Henning Kamp" wrote: > -------- > parv/FreeBSD writes: > > > > Does backlight(8) works for you? > > > > Thanks for the clue. It does! It does ... > > > > - I get the same number back via "backlight" without any arguments as > > what I gave it earlier. There was no reporting of value being > > subtracted by one; > > Sorry for the delay in reporting back. > > I consistently read one less back, except for 0 and 100. Even 50 ? > (This could easily be a BIOS bug) At first I though so too but I'll need to check if this isn't a rounding error between backlight(4) and linuxkpi wrappers. I know that some hardware don't have a perfect pwm controller for the backlight and so you have only some steps that it can do (but you don't know them). > It also looks like the "no-op" behaviour I reported previously have > gone away with my latest kernel update. Weird, nothing has changed for a while in this area but happy that it's fixed ;) > But I see a new behaviour, but this may be intentional: When it > comes out of screen-blanking, it goes to 100 (and reports 100). I'm not too surprised about this behavior, there is probably something that we could do about it but this will need more digging in linux framework and the drm drivers. > Also happens when an external monitor is connected, which is a > bit annoying... So if you have, let's say brightness at 50%, and you plug an external monitor, brightness goes up to 100% ? > -- > Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 > phk@FreeBSD.ORG | TCP/IP since RFC 956 > FreeBSD committer | BSD since 4.3-tahoe > Never attribute to malice what can adequately be explained by incompetence. > -- Emmanuel Vadot