From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753291AbcCGQ5n (ORCPT ); Mon, 7 Mar 2016 11:57:43 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:55634 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752418AbcCGQ5e (ORCPT ); Mon, 7 Mar 2016 11:57:34 -0500 Date: Mon, 7 Mar 2016 08:57:33 -0800 From: Greg KH To: Sudip Mukherjee Cc: Wolfram Sang , linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org Subject: Re: [PATCH] i2c: i2c-core: do not use bus internal data Message-ID: <20160307165733.GA20093@kroah.com> References: <1457351357-13457-1-git-send-email-sudipm.mukherjee@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1457351357-13457-1-git-send-email-sudipm.mukherjee@gmail.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 07, 2016 at 05:19:17PM +0530, Sudip Mukherjee wrote: > The variable p is a data structure which is used by the driver core > internally and it is not expected that busses will be directly accessing > these driver core internal only data. > > Signed-off-by: Sudip Mukherjee > --- > > Reference of Greg's comment about it at: > https://lkml.org/lkml/2016/3/5/171 > > drivers/i2c/i2c-core.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c > index 2949ab3..2f31fb5 100644 > --- a/drivers/i2c/i2c-core.c > +++ b/drivers/i2c/i2c-core.c > @@ -73,6 +73,7 @@ static struct device_type i2c_client_type; > static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver); > > static struct static_key i2c_trace_msg = STATIC_KEY_INIT_FALSE; > +static bool is_registered; > > void i2c_transfer_trace_reg(void) > { > @@ -1529,7 +1530,7 @@ static int i2c_register_adapter(struct i2c_adapter *adap) > int res = 0; > > /* Can't register until after driver model init */ > - if (unlikely(WARN_ON(!i2c_bus_type.p))) { > + if (unlikely(WARN_ON(!is_registered))) { > res = -EAGAIN; > goto out_list; > } Minor nit, likely/unlikely should only be used on very "hot paths" where the difference if it is not included can be measured. the "register a device" path is not "hot" at all. That being said, the patch is fine with me: Acked-by: Greg Kroah-Hartman