From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maxime Ripard Subject: Re: [PATCH v2 1/6] spi: core: handle timeout error from transfer_one() Date: Wed, 4 Apr 2018 09:08:18 +0200 Message-ID: <20180404070817.6cens44jvlmdaxtm@flea> References: <20180403152905.1524-1-ssuloev@orpaltech.com> <20180403152905.1524-2-ssuloev@orpaltech.com> <20180403155224.GA11578@sirena.org.uk> <20180403161824.GB11578@sirena.org.uk> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="jixbiuhukrqgg4cn" Cc: Mark Brown , Chen-Yu Tsai , linux-spi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org To: Sergey Suloev Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-spi.vger.kernel.org --jixbiuhukrqgg4cn Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Apr 03, 2018 at 07:24:11PM +0300, Sergey Suloev wrote: > On 04/03/2018 07:18 PM, Mark Brown wrote: > > On Tue, Apr 03, 2018 at 07:00:55PM +0300, Sergey Suloev wrote: > > > On 04/03/2018 06:52 PM, Mark Brown wrote: > > > > On Tue, Apr 03, 2018 at 06:29:00PM +0300, Sergey Suloev wrote: > > > > > As long as sun4i/sun6i SPI drivers have overriden the default > > > > > "wait for completion" procedure then we need to properly > > > > > handle -ETIMEDOUT error from transfer_one(). > > > > Why is this connected to those drivers specifically? > > > These 2 drivers have their own "waiting" code and not using the code = =66rom > > > SPI core. > > Does this not apply to any other driver - why is this something we only > > have to do when these drivers do it? That's what's setting off alarm > > bells. >=20 > sun4i/sun6i drivers have let's say "smart" waiting while SPI core uses a > fixed interval to wait. >=20 > I can't say for every SPI driver in kernel, that's outside of my area of > expertise. I'm not sure what's specific about the sun4i / sun6i case here. Your patch doesn't have anything to do with the delay before the timeout, but the fact that we return -ETIMEDOUT in the first place. And I'm pretty sure that papering over an error returned by a driver is not the right thing to do. Maxime --=20 Maxime Ripard, Bootlin (formerly Free Electrons) Embedded Linux and Kernel engineering https://bootlin.com --jixbiuhukrqgg4cn Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEE0VqZU19dR2zEVaqr0rTAlCFNr3QFAlrEeeEACgkQ0rTAlCFN r3RTyg/+LLCk5LJ18AFnqN1WDMGyPF5NEgPeSYBdWEoBlP79QTs5DKYzgK/CW8/I t3WkryZBNoBC0jb9NWa+YLjacANk4egs6hK7rY3kjkbIDx7Ni9QlEZpYFll0gZL9 f9mqE++6nIlS3qpFJNU+6g46NghIy0WhB3GhmXyzdb4meFMYo6KjiPLuqRSfjx2N CpZ0gzRTKPGPLj13q0ZPBqHAID5hhNIDG954rYBOKyZh+ykSG2pIH0Z98DB7XWau d3jBo50TI7XP3yEe3UkUlIgLa5j9PVIJyiZk9S2fDJqSeA7Oq5YLddkMsJtvsXcO WXW8lFUrRJLrVmaerz04ga98ad4JO8LiXyXuGGMYoj63dJ++cM7kUjjzGXiMzuBB jPDcUJaGZRV5mp2CzHpeecCtR0xPm0MquJcQp0tO7THWeSkttuqmb6MkJCMcEx9t o1NhKwYZc/hyKpFnIYeZRNIobscfouo5t5np7pB1W7N8jSSFCr6Nyiu/XLDHF+h3 VmigIkT7HkkcHyDgItFK5eiw0TY1yGJtq58U6CxsMLdRpyTM7eWCJRY4ofGmncwa c0d/eZ1QF6PLIlNCNxJMYSXa1iglLeXOuPUxj+fYzZPR7eiSXUFlwqAwFP21u2WD nGGSG8ySISUT/v8j9hrzPG0CKk5Lmo3mDZi72iVAHIDPdBoUyMM= =ZjNx -----END PGP SIGNATURE----- --jixbiuhukrqgg4cn--