From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ED44DC433FF for ; Wed, 14 Aug 2019 10:08:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C44AD2067D for ; Wed, 14 Aug 2019 10:08:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727184AbfHNKH7 (ORCPT ); Wed, 14 Aug 2019 06:07:59 -0400 Received: from sauhun.de ([88.99.104.3]:47182 "EHLO pokefinder.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725955AbfHNKH7 (ORCPT ); Wed, 14 Aug 2019 06:07:59 -0400 Received: from localhost (p54B33326.dip0.t-ipconnect.de [84.179.51.38]) by pokefinder.org (Postfix) with ESMTPSA id 42A722C311C; Wed, 14 Aug 2019 12:07:57 +0200 (CEST) Date: Wed, 14 Aug 2019 12:07:56 +0200 From: Wolfram Sang To: Fuqian Huang , Russell King Cc: Greg Kroah-Hartman , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] i2c: avoid sleep in IRQ context Message-ID: <20190814100756.GF1511@ninjato> References: <20190807071807.17488-1-huangfq.daxian@gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="cpvLTH7QU4gwfq3S" Content-Disposition: inline In-Reply-To: <20190807071807.17488-1-huangfq.daxian@gmail.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --cpvLTH7QU4gwfq3S Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Aug 07, 2019 at 03:18:07PM +0800, Fuqian Huang wrote: > i2c_pxa_handler -> i2c_pxa_irq_txempty -> > i2c_pxa_reset -> i2c_pxa_set_slave -> i2c_pxa_wait_slave >=20 > As i2c_pxa_handler is an interrupt handler, it will finally > calls i2c_pxa_wait_slave which calls msleep. >=20 > Add in_interrupt check before msleep to avoid sleep > in IRQ context. > When in interrupt context, use mdelay instead of msleep. >=20 > Signed-off-by: Fuqian Huang Adding RMK to CC because he is the PXA I2C slave user I know of. > --- > drivers/i2c/busses/i2c-pxa.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) >=20 > diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c > index 2c3c3d6935c0..876e693bafd9 100644 > --- a/drivers/i2c/busses/i2c-pxa.c > +++ b/drivers/i2c/busses/i2c-pxa.c > @@ -456,7 +456,10 @@ static int i2c_pxa_wait_slave(struct pxa_i2c *i2c) > return 1; > } > =20 > - msleep(1); > + if (in_interrupt()) > + mdelay(1); > + else > + msleep(1); > } > =20 > if (i2c_debug > 0) > --=20 > 2.11.0 >=20 --cpvLTH7QU4gwfq3S Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAl1T3XwACgkQFA3kzBSg KbZRyw//cTr0sByawJ6jOB3ewub37WDzoXSmdd3Q9hCacD8Ya66zum7xtMEbO2uq dG5djFuGXNRsUWQlYo66bxUYHm7zqqYt4EKvKxqJ3WKfreUW805Tjz6HkhCbZvqd 5euudhyXvpW6cKLU1zBL6hCvf3rPXbigDAiEuJdTin5HrOsNtBeTpceLN1YClze8 fIJAKfF3zINoI2rvH9Y3lQubb89FohC6kDvwQ3plJtc5a2zFT31BKNI0HaodmKVs jGUUTYqAAXr/o/tvTodoZGE9I3dfOraW6qDfv2uetQQRLeaU5c+6BUxqyJIBmwp3 Btjx+zSXx+/4EBfSKWFnur/VQlhozE2b+tDSlFsnSMFRGr78pNs4sP2yIdGx2WT8 XCNDiwGgFD4FIGmtzuyBOjwu8XwktDDPgMgK5RXgjXJY/kN6pWZRhYAhwBcRzPjo MOD+CJ9Gz49xgigRvO5BwHb+EGK2eh8jMDN6CcjIUwttIyA9QFn9Bmd49yu0YlYc M3ZC8u29HR8kraIv+qL61xKVw1+0ZRNKUAV2/nIpn0Quv1AtGPa3iEgny03nseIF emlAKD9GZ58FQBzUBeNHbulWnbfVrcNiBeEXEKiRPa/DBwr8ZeAWstnCLOfd55UH xA2OXGyXzxRpTdoFwlmR3VLIB2r0QPWJOJtVwsNfi+WEcns7G9I= =RuWr -----END PGP SIGNATURE----- --cpvLTH7QU4gwfq3S--