From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755233AbbAITfe (ORCPT ); Fri, 9 Jan 2015 14:35:34 -0500 Received: from mail-lb0-f175.google.com ([209.85.217.175]:39566 "EHLO mail-lb0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751489AbbAITfc (ORCPT ); Fri, 9 Jan 2015 14:35:32 -0500 Message-ID: <54B02D7F.7040501@cogentembedded.com> Date: Fri, 09 Jan 2015 22:35:27 +0300 From: Sergei Shtylyov Organization: Cogent Embedded User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 MIME-Version: 1.0 To: Wolfram Sang , linux-i2c@vger.kernel.org CC: linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-mips@linux-mips.org, Benjamin Herrenschmidt , Ludovic Desroches , Yingjoe Chen , linux-kernel@vger.kernel.org Subject: Re: [RFC 02/11] i2c: add quirk checks to core References: <1420824103-24169-1-git-send-email-wsa@the-dreams.de> <1420824103-24169-3-git-send-email-wsa@the-dreams.de> In-Reply-To: <1420824103-24169-3-git-send-email-wsa@the-dreams.de> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello. On 01/09/2015 08:21 PM, Wolfram Sang wrote: > Let the core do the checks if HW quirks prevent a transfer. Saves code > from drivers and adds consistency. > Signed-off-by: Wolfram Sang > --- > drivers/i2c/i2c-core.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 53 insertions(+) > > diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c > index 39d25a8cb1ad..7b10a19abf5b 100644 > --- a/drivers/i2c/i2c-core.c > +++ b/drivers/i2c/i2c-core.c > @@ -2063,6 +2063,56 @@ module_exit(i2c_exit); > * ---------------------------------------------------- > */ > > +/* Check if val is exceeding the quirk IFF quirk is non 0 */ > +#define i2c_quirk_exceeded(val, quirk) ((quirk) && ((val) > (quirk))) > + > +static int i2c_quirk_error(struct i2c_adapter *adap, struct i2c_msg *msg, char *err_msg) > +{ > + dev_err(&adap->dev, "quirk: %s (addr 0x%04x, size %u)\n", err_msg, msg->addr, msg->len); > + return -EOPNOTSUPP; > +} Always returning the same value doesn't make much sense. Are you trying to save space on the call sites? [...] > @@ -2080,6 +2130,9 @@ int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) > unsigned long orig_jiffies; > int ret, try; > > + if (adap->quirks && i2c_check_for_quirks(adap, msgs, num)) So, you only check for non-zero result of this function? Perhaps it makes sense to return true/false instead? > + return -EOPNOTSUPP; > + WBR, Sergei