From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x227a1NlzjpaSV8n9qX4Lti8o0r2NoALJFKrxqb8h1vWnVW99Xl0PnR++3Q4u3V4Lj030iser ARC-Seal: i=1; a=rsa-sha256; t=1518449179; cv=none; d=google.com; s=arc-20160816; b=Q15RS3ZLZx8oTF1qmNX9q2kXv/kUv7CesgLH3FPXLfyo7iT850mRo2npSRXyvgWr5f pKh2zTcEJyp7VGgIZCbhDWolX1bvgIJgZbFSi3AiCh3/3/KjcwgLTCBOojht5l7+ViD4 6cFY8WmBhSV60glD1aQtDlN6jlFzHXX0xCeSKSRtSSILyWoHTa+1vXQ8bzDhSM6F0E3q Mt+xHg1OD5LMPeh6OowGu+86MyDYw+36/p91FM5ZBHmdyu+N6IdStQEgZlSZ84/FQT9s U+Yxcyr+WEJCy8miZ38kPN/W5L+xYAmFx70ldcQ7uKmhPjxWV5OxSvZSguYIvpYrkTD9 /x5Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=user-agent:in-reply-to:content-disposition:mime-version:references :message-id:subject:cc:to:from:date:arc-authentication-results; bh=vcak6BnBC9FQEz3w7qOBB8cgb3TjwUyZ5B2Y5FQghz8=; b=eS+sD4X3fNxwmGIhR66+gajhhhXFvtsMJvAxTc86FKo+n3uUDxJ+raHjPORxTbYvVb Ha5y2x9hz/L49VOepykLU3QonMqNZgTeWKyrWd6FJNe759S1nr7Ojn9WXxrDhyOdWJy2 drQR1kQpuOncdIwy9pUo8I6AHEc2Vxo7LLD5bnWrAop61zhOMry8tWvksvz7FAeoD9WR 9xam+7OOwr+BhCabl9/h9ujb/wV8op9JalOWrSgQ8VC+tei3ZdlTgZW9rVuQpJlyuLc4 0O9+IwpYWAINpQSnWp31F6UnHhwqvocuKS5zVWUP5VtJQ+WENn1Q/oAvTGqzj8YM1Z8u mUxQ== ARC-Authentication-Results: i=1; mx.google.com; spf=neutral (google.com: 195.113.26.193 is neither permitted nor denied by best guess record for domain of pavel@ucw.cz) smtp.mailfrom=pavel@ucw.cz Authentication-Results: mx.google.com; spf=neutral (google.com: 195.113.26.193 is neither permitted nor denied by best guess record for domain of pavel@ucw.cz) smtp.mailfrom=pavel@ucw.cz Date: Mon, 12 Feb 2018 16:26:18 +0100 From: Pavel Machek To: Johan Hovold Cc: "H. Nikolaus Schaller" , Mark Rutland , DTML , Thierry Reding , Jonathan Cameron , Arnd Bergmann , Tony Lindgren , Greg Kroah-Hartman , Russell King , Linux Kernel Mailing List , Rob Herring , Kevin Hilman , =?iso-8859-1?Q?Beno=EEt?= Cousson , kernel@pyra-handheld.com, Discussions about the Letux Kernel , linux-omap , Andreas =?iso-8859-1?Q?F=E4rber?= , Linux ARM Subject: Re: [Letux-kernel] [PATCH v5 3/5] misc serdev: Add w2sg0004 (gps receiver) power control driver Message-ID: <20180212152618.GC13962@amd> References: <5494ad34b39a6c62601e3747440268dfb3be7d5a.1512114576.git.hns@goldelico.com> <20171222124427.GI3374@localhost> <91850CC3-B280-4701-9D07-96AFF3A79A6F@goldelico.com> <90F9A8E4-035A-4A9E-8AAB-757491D63E69@goldelico.com> <20180112153903.GB5992@localhost> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="dkEUBIird37B8yKS" Content-Disposition: inline In-Reply-To: <20180112153903.GB5992@localhost> User-Agent: Mutt/1.5.23 (2014-03-12) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1584169666984958099?= X-GMAIL-MSGID: =?utf-8?q?1592209367346884866?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: --dkEUBIird37B8yKS Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi! > > Let's restart this discussion and focus on the main roadblock (others > > are minor details which can be sorted out later). > >=20 > > If it feels like a hack, the key issue seems to me to be the choice of > > the API to present the GPS data to user space. Right? >=20 > Or even more fundamentally, does this belong in the kernel at all? Yes, it does. > Given that we'd still depend on gpsd and other, proprietary, daemons to > actually parse and use (also for control) the plethora of GPS protocols > available, it may even be best to just keep it all in user space. No. We'd want to move away from gpsd in the long term. (/dev/input/mice was in similar situation.) > Now, if we'd ever have a proper GPS framework that handled everything in > kernel space (i.e. no more gpsd) then we would be able to write kernel > drivers that also take care of PM. But perhaps that's unlikely to ever > be realised given the state of things (proprietary protocols, numerous > quirky implementations, etc). That is what needs to happen. > The kernel is probably not the place to be working around issues like > that, even if serdev at least allows for such hacks to be fairly > isolated in drivers (unlike some of the earlier proposals touching core > code). Oh, kernel is indeed right place to provide hardware abstraction -- and that includes bug workarounds. We'd like unmodified userspace to run on any supported hardware, remember? Pavel --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo= g.html --dkEUBIird37B8yKS Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAlqBshoACgkQMOfwapXb+vLq0ACfa+0cUfIudCx3JKPfpMHeQ9Fk se8AoIjq1ci/aJ0lgBOdyzieOOILfG/Q =amcf -----END PGP SIGNATURE----- --dkEUBIird37B8yKS--