From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C15F73AA9E2; Tue, 8 Sep 2026 20:24:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788899074; cv=none; b=Ed+sqmEhk7E0dSCcuI1suf4FxCBZpAW9iGnlpqGTbusvqj5qL0B9t8dkv8Eo9MCXL+4QSsDIefYWe9nD4NoJ+ms565jAk+lAWeWU4pbbfBhS+WCJmO+iSPX4UMQC6pADqWactF8kdV7gxqNrG8p5EDMf7PuK0grlaLf7l1wheWQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788899074; c=relaxed/simple; bh=34UMiWTgxcFBqUNYh11YSBmRYxGFZiGVkCLTRzlNjdY=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=gcfLeWrjauxpQB6KKPZmdWgLpPaN5mx9fLz0yoLnz5YDGV0399Hhms9wiXKYcy75na1Xaag1cwB06rs8Hyz3GpwLOYzqJnsLTnzq4fatMbNFXxvAmd1Uk8oLsKXxN6nuTQXJhiRf1UVEgfiiH0ruZ3LioJD0KZNGPn5qKmPWKqU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=n13BLIwJ; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="n13BLIwJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B5FF31F00A3A; Tue, 8 Sep 2026 20:24:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788899073; bh=UX81FKHggDlYBKlQeaoEzIUHgB632Ksy7gdLpHI4rVY=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=n13BLIwJUvc/OQ5IesL7KDPLWb0H+mPh8H9Cy3ItVDb5BGON0ikp86TlzyYX7EaHR 3ePPwGuAnceTgnPER+uk8XpmI9RTdqctlshgC29YgNuiZoHhZ6cEP+/0mjsHF69Ycf fAzuq0xDMnj/rJWwi0U5PqMfFrXX2cvN5v00YNvIzIxhQ8zWM7c/mhX+QnTAtBBpWT ZU3jSm49HKaF6HjrwQPDrlsh9Iu1Ay1CKpMuvfpXfdKokzTGCbUyAt5OMjwatkpsk7 C3IpYx6T0VZoqFUM+e10ISLdebrmDk17Ae3XUifqAczThEmuBjdWAFZsCtA/SO67AN bIxrG97DoV5qg== Message-ID: <1b51428b-5dcd-4fdc-8f4e-d16ab14426a1@kernel.org> Date: Tue, 8 Sep 2026 22:24:27 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 11/22] thunderbolt: Find Apple VSE capability during startup To: Joshua Peisach Cc: Konrad Dybcio , Conor Dooley , Krzysztof Kozlowski , linux-usb@vger.kernel.org, Neal Gompa , Janne Grunau , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Yehezkel Bernat , Mika Westerberg , Andreas Noever , Philipp Zabel , asahi@lists.linux.dev, Rob Herring , Heikki Krogerus , linux-arm-kernel@lists.infradead.org, Greg Kroah-Hartman References: <20260906-b4-apple-soc-tbt-v2-0-1f80085f93fb@kernel.org> <20260906-b4-apple-soc-tbt-v2-11-1f80085f93fb@kernel.org> Content-Language: en-US From: Sven Peter In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 9/7/26 15:38, Joshua Peisach wrote: > On Sun Sep 6, 2026 at 2:36 PM EDT, Sven Peter wrote: >> Only Apple Silicon host routers have the Apple vendor-specific extended >> capability. Look it up when the software connection manager starts and >> store its offset in the root switch. >> >> The Apple NHI driver can then use the stored offset when programming >> cable information without searching the router capabilities itself. >> >> Signed-off-by: Sven Peter >> --- >>  drivers/thunderbolt/tb.c      | 4 ++++ >>  drivers/thunderbolt/tb.h      | 2 ++ >>  drivers/thunderbolt/tb_regs.h | 1 + >>  3 files changed, 7 insertions(+) >> >> diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c >> index bf1c192ec10a..d2832323cc36 100644 >> --- a/drivers/thunderbolt/tb.c >> +++ b/drivers/thunderbolt/tb.c >> @@ -3025,6 +3025,10 @@ static int tb_start(struct tb *tb, bool reset) >>          return dev_err_probe(tb->nhi->dev, PTR_ERR(tb->root_switch), >>                       "failed to allocate host router\n"); >> >> +    ret = tb_switch_find_vse_cap(tb->root_switch, TB_VSE_CAP_APPLE); >> +    if (ret > 0) >> +        tb->root_switch->cap_vsec_apple = ret; >> + > > Nitpick: I *think* based on the surrounding code that this can be > simplified to "if (ret)" > No, ret < 0 is an error and if something goes wrong cap_vsec_apple must remain zero and not whatever errno tb_switch_find_vse_cap returned. Sven