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=-12.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 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 D4E84C4727C for ; Tue, 29 Sep 2020 15:54:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7278F20773 for ; Tue, 29 Sep 2020 15:54:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601394875; bh=U3wTRYS5La8oZ9gPFQ2NLqNVrKaawXqnWmHLf7jBugo=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=JL6SGno+DR4ctxXWfPC8Q8pROT9hj/oOmJVsJ5N+zHYYF9SMD0oRTTZvmdhTUYTXP 3jd3auDHXsJXI+fzxs1zSnXX1TYBYHoQq9cUTdkAMXt4SPIRICYYRdCqxt8HGC47pX 1Ub4iHrp5DWt6GTX28AY3onKBZvGvrmOj2ry9YlQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728492AbgI2Pyf (ORCPT ); Tue, 29 Sep 2020 11:54:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:45358 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725497AbgI2Pye (ORCPT ); Tue, 29 Sep 2020 11:54:34 -0400 Received: from archlinux (cpc149474-cmbg20-2-0-cust94.5-4.cable.virginm.net [82.4.196.95]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 98D2820739; Tue, 29 Sep 2020 15:54:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601394873; bh=U3wTRYS5La8oZ9gPFQ2NLqNVrKaawXqnWmHLf7jBugo=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=vcEe5K7ZTrM6qdlKpNQgRGLseTn+Z6feRuPNomWgf6sKL2sbO6e/9hUYdfC2q0l06 b0CN2OOqC971x/OGRYG2GbiANlDA75+8azjPrmgpGl0rrS7A6QuHScdzTw0lbNiIW5 oguiNtny8psnRx8jhn+BPl3ZZN/5efC564KKSQU8= Date: Tue, 29 Sep 2020 16:54:28 +0100 From: Jonathan Cameron To: Alexandru Ardelean Cc: , , , , , Subject: Re: [PATCH 1/2] iio: adc: at91_adc: use of_device_get_match_data() helper Message-ID: <20200929165428.15ac9e4c@archlinux> In-Reply-To: <20200928125424.35921-1-alexandru.ardelean@analog.com> References: <20200928125424.35921-1-alexandru.ardelean@analog.com> X-Mailer: Claws Mail 3.17.6 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On Mon, 28 Sep 2020 15:54:23 +0300 Alexandru Ardelean wrote: > This tries to solve a warning reported by the lkp bot: > > >> drivers/iio/adc/at91_adc.c:1439:34: warning: unused variable > >> 'at91_adc_dt_ids' [-Wunused-const-variable] > static const struct of_device_id at91_adc_dt_ids[] = { > ^ > 1 warning generated. > > This shows up with 'compiler: clang version 12.0.0' and W=1 (as the bot > mentions). > > Forward declarations for global variables can be a bit weird; forward > function declarations are more common. Hi, That's not the forward declaration that it is complaining about... It's a reasonable patch anyway, but doesn't fix that warning which is about of_match_ptr and the lack of #ifdef CONFIG_OF around the actual definition. For the bug warning, I'd add add a Kconfig dependency on OF. It doesn't make any sense to allow building this driver without that. So resend this as a simple tidy up patch and another one adding that build dependency. Thanks, Jonathan > > Maybe another fix for this would have been to prefix with 'extern' the > 'at91_adc_dt_ids' variable, thus making it more friendly as a forward > declaration. It would look weird, but it would work. > > But, we can avoid that forward declaration altogether simply by obtaining > the private data with of_device_get_match_data(). > > This appeared after commit 4027860dcc4c ("iio: Kconfig: at91_adc: add > COMPILE_TEST dependency to driver"), which put this driver on the lkp's bot > radar. > > Reported-by: kernel test robot > Signed-off-by: Alexandru Ardelean > --- > drivers/iio/adc/at91_adc.c | 5 +---- > 1 file changed, 1 insertion(+), 4 deletions(-) > > diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c > index 9b2c548fae95..c9ec0a4a357e 100644 > --- a/drivers/iio/adc/at91_adc.c > +++ b/drivers/iio/adc/at91_adc.c > @@ -829,8 +829,6 @@ static u32 calc_startup_ticks_9x5(u32 startup_time, u32 adc_clk_khz) > return ticks; > } > > -static const struct of_device_id at91_adc_dt_ids[]; > - > static int at91_adc_probe_dt_ts(struct device_node *node, > struct at91_adc_state *st, struct device *dev) > { > @@ -878,8 +876,7 @@ static int at91_adc_probe_dt(struct iio_dev *idev, > if (!node) > return -EINVAL; > > - st->caps = (struct at91_adc_caps *) > - of_match_device(at91_adc_dt_ids, &pdev->dev)->data; > + st->caps = (struct at91_adc_caps *)of_device_get_match_data(&pdev->dev); > > st->use_external = of_property_read_bool(node, "atmel,adc-use-external-triggers"); >