From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752399AbcLGMC2 (ORCPT ); Wed, 7 Dec 2016 07:02:28 -0500 Received: from mail-wm0-f43.google.com ([74.125.82.43]:35891 "EHLO mail-wm0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751592AbcLGMCZ (ORCPT ); Wed, 7 Dec 2016 07:02:25 -0500 Subject: Re: [PATCH v4 6/7] IIO: add STM32 timer trigger driver To: Benjamin Gaignard , Lee Jones References: <1481027929-13704-1-git-send-email-benjamin.gaignard@st.com> <1481027929-13704-7-git-send-email-benjamin.gaignard@st.com> <20161206131635.GJ25385@dell.home> <20161207105002.GA3625@dell.home> Cc: robh+dt@kernel.org, Mark Rutland , alexandre.torgue@st.com, devicetree@vger.kernel.org, Linux Kernel Mailing List , Thierry Reding , linux-pwm@vger.kernel.org, Jonathan Cameron , knaack.h@gmx.de, Lars-Peter Clausen , Peter Meerwald-Stadler , linux-iio@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Fabrice Gasnier , Gerald Baeza , Arnaud Pouliquen , Linus Walleij , Linaro Kernel Mailman List , Benjamin Gaignard From: Daniel Thompson Message-ID: <5dcec09c-8b4b-4cc2-ce3f-fde86366ec05@linaro.org> Date: Wed, 7 Dec 2016 12:01:52 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/12/16 11:00, Benjamin Gaignard wrote: > 2016-12-07 11:50 GMT+01:00 Lee Jones : >> On Tue, 06 Dec 2016, Benjamin Gaignard wrote: >> >>> [snip] >>>>> + >>>>> +static const char * const triggers0[] = { >>>>> + TIM1_TRGO, TIM1_CH1, TIM1_CH2, TIM1_CH3, TIM1_CH4, NULL, >>>>> +}; >>>>> + >>>>> +static const char * const triggers1[] = { >>>>> + TIM2_TRGO, TIM2_CH1, TIM2_CH2, TIM2_CH3, TIM2_CH4, NULL, >>>>> +}; >>>>> + >>>>> +static const char * const triggers2[] = { >>>>> + TIM3_TRGO, TIM3_CH1, TIM3_CH2, TIM3_CH3, TIM3_CH4, NULL, >>>>> +}; >>>>> + >>>>> +static const char * const triggers3[] = { >>>>> + TIM4_TRGO, TIM4_CH1, TIM4_CH2, TIM4_CH3, TIM4_CH4, NULL, >>>>> +}; >>>>> + >>>>> +static const char * const triggers4[] = { >>>>> + TIM5_TRGO, TIM5_CH1, TIM5_CH2, TIM5_CH3, TIM5_CH4, NULL, >>>>> +}; >>>>> + >>>>> +static const char * const triggers5[] = { >>>>> + TIM6_TRGO, NULL, >>>>> +}; >>>>> + >>>>> +static const char * const triggers6[] = { >>>>> + TIM7_TRGO, NULL, >>>>> +}; >>>>> + >>>>> +static const char * const triggers7[] = { >>>>> + TIM8_TRGO, TIM8_CH1, TIM8_CH2, TIM8_CH3, TIM8_CH4, NULL, >>>>> +}; >>>>> + >>>>> +static const char * const triggers8[] = { >>>>> + TIM9_TRGO, TIM9_CH1, TIM9_CH2, NULL, >>>>> +}; >>>>> + >>>>> +static const char * const triggers9[] = { >>>>> + TIM12_TRGO, TIM12_CH1, TIM12_CH2, NULL, >>>>> +}; >>>>> + >>>>> +static const void *triggers_table[] = { >>>>> + triggers0, >>>>> + triggers1, >>>>> + triggers2, >>>>> + triggers3, >>>>> + triggers4, >>>>> + triggers5, >>>>> + triggers6, >>>>> + triggers7, >>>>> + triggers8, >>>>> + triggers9, >>>>> +}; >>>> >>>> What about: >>>> >>>> static const char * const triggers[][] = { >>>> { TIM1_TRGO, TIM1_CH1, TIM1_CH2, TIM1_CH3, TIM1_CH4, NULL }, >>>> { TIM2_TRGO, TIM2_CH1, TIM2_CH2, TIM2_CH3, TIM2_CH4, NULL }, >>>> { TIM3_TRGO, TIM3_CH1, TIM3_CH2, TIM3_CH3, TIM3_CH4, NULL }, >>>> { TIM4_TRGO, TIM4_CH1, TIM4_CH2, TIM4_CH3, TIM4_CH4, NULL }, >>>> { TIM5_TRGO, TIM5_CH1, TIM5_CH2, TIM5_CH3, TIM5_CH4, NULL }, >>>> { TIM6_TRGO, NULL }, >>>> { TIM7_TRGO, NULL }, >>>> { TIM8_TRGO, TIM8_CH1, TIM8_CH2, TIM8_CH3, TIM8_CH4, NULL }, >>>> { TIM9_TRGO, TIM9_CH1, TIM9_CH2, NULL }, >>>> { TIM12_TRGO, TIM12_CH1, TIM12_CH2, NULL } >>>> }; >>> >>> I can't because the second dimension of the array isn't fix. >>> I could have between 2 and 6 elements per row... to create a dual dimension >>> array I would have to add NULL entries like that: >>> >>> #define MAX_TRIGGERS 6 >>> >>> static const void *triggers_table[][MAX_TRIGGERS] = { >>> { TIM1_TRGO, TIM1_CH1, TIM1_CH2, TIM1_CH3, TIM1_CH4, NULL,}, >>> { TIM2_TRGO, TIM2_CH1, TIM2_CH2, TIM2_CH3, TIM2_CH4, NULL,}, >>> { TIM3_TRGO, TIM3_CH1, TIM3_CH2, TIM3_CH3, TIM3_CH4, NULL,}, >>> { TIM4_TRGO, TIM4_CH1, TIM4_CH2, TIM4_CH3, TIM4_CH4, NULL,}, >>> { TIM5_TRGO, TIM5_CH1, TIM5_CH2, TIM5_CH3, TIM5_CH4, NULL,}, >>> { TIM6_TRGO, NULL, NULL, NULL, NULL, NULL,}, >>> { TIM7_TRGO, NULL, NULL, NULL, NULL, NULL,}, >>> { TIM8_TRGO, TIM8_CH1, TIM8_CH2, TIM8_CH3, TIM8_CH4, NULL,}, >>> { TIM9_TRGO, TIM9_CH1, TIM9_CH2, NULL, NULL, NULL,}, >>> { TIM12_TRGO, TIM12_CH1, TIM12_CH2, NULL, NULL, NULL,}, >>> }; >> >> It was just an idea, not a tested implementation. >> >> I don't understand why you have to pad with NULLs, but either way, it >> looks much better than before and saves lots of lines of code. > > I have tested it this morning and it works fine so I will include it in v5. > I use NULL as limit when iterate in the table and for table padding too. If the initializer is shorter than the array then the array will be implicitly zero/NULL padded. I don't think there is any need to type out all the NULLs (not even at -Wall). Daniel.