From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 475871E1E13; Mon, 31 Mar 2025 11:15:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743419703; cv=none; b=OdNStPAWKmXWMzutdNseG/VAYM9kNk1uJYXeQtMZuX60xXH5FNN5GzvgkGD91un3eYPR1qL8CgwUIABjPYbHhUlPxkbKHnj9aN4FTxfXsl3ToMImcg3M9hQ0XTIB+gwXXIU5IU5MCBptQk7+b78DxELoBgDGkFjxetnnZGxJqJk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743419703; c=relaxed/simple; bh=nLlydRF7GjIqMiKieOsgcX9xT9XN72KxiEV9LmXP8N4=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=syPQUBuC8Rm7lGYsmr4dzYOpdSw8QPNVMtddsxWSaji0/bsLJj7xjnNd5tIz5SuYvq40MP7GYdUewOElP6LXIqmG38H9N1QxNQX5odnwC4XxubLvqKBAO/Wi4Oz8MsRiMskFJi7+tc9miEqmV4Ap2tgpbQN4rNJkGDrMpum4/Lk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=rdzXXBSe; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="rdzXXBSe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2554AC4CEE3; Mon, 31 Mar 2025 11:14:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1743419702; bh=nLlydRF7GjIqMiKieOsgcX9xT9XN72KxiEV9LmXP8N4=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=rdzXXBSeHugK1gkHaEL3OjX2zNy9EStsQbhroiPL4OTd/3N58y2VCflDcku+iOdw/ OLijwlfMjBt6GJ7VOMshJFAfzGDsSTRWoURff4E3LgkyUw/uoJwKwlAySMaWLKvwJL kOut+N2bodGxnDcBQzTHRx+WkERZcrypJKijk7wQ3rI7qY9+HSD4vlJyJwmHOPi0XM dgI/fWwNnfBVH53xKO/KkRSPLWJcwztSmlQ9p2KME7J2bGBPaRaEx8J/k82q2ttT9I CgcfnTEI8Y0ZooJMWRS4H5m/CaZPBLlI2Y7bt7WpN5wl9O1ucXVsLZFIOkETv8J3Wk RrLRdG44En05g== Date: Mon, 31 Mar 2025 12:14:53 +0100 From: Jonathan Cameron To: Matti Vaittinen Cc: Matti Vaittinen , Lars-Peter Clausen , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Nuno Sa , David Lechner , Javier Carrasco , linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 5/6] iio: adc: ti-adc128s052: Simplify using guard(mutex) Message-ID: <20250331121453.690642f7@jic23-huawei> In-Reply-To: <93a9d7ab74cd045949a2e2b6301f29c7d83d72ea.1742474322.git.mazziesaccount@gmail.com> References: <93a9d7ab74cd045949a2e2b6301f29c7d83d72ea.1742474322.git.mazziesaccount@gmail.com> X-Mailer: Claws Mail 4.3.0 (GTK 3.24.48; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Mon, 31 Mar 2025 11:03:44 +0300 Matti Vaittinen wrote: > Error path in ADC reading function can be slighly simplified using the > guard(mutex). Do just that. > > Also, document the mutex purpose while at it. Ah. I should have read on before earlier comment! That's what I get for an efficient linear pass of patches :) > > Signed-off-by: Matti Vaittinen > --- > drivers/iio/adc/ti-adc128s052.c | 11 ++++------- > 1 file changed, 4 insertions(+), 7 deletions(-) > > diff --git a/drivers/iio/adc/ti-adc128s052.c b/drivers/iio/adc/ti-adc128s052.c > index 90b23c68daea..c68ee4e17a03 100644 > --- a/drivers/iio/adc/ti-adc128s052.c > +++ b/drivers/iio/adc/ti-adc128s052.c > @@ -9,6 +9,7 @@ > * https://www.ti.com/lit/ds/symlink/adc124s021.pdf > */ > > +#include > #include > #include > #include > @@ -26,6 +27,7 @@ struct adc128 { > struct spi_device *spi; > > struct regulator *reg; > + /* Serialize the SPI 'write-channel + read data' accesses */ > struct mutex lock; > > __be16 buffer __aligned(IIO_DMA_MINALIGN); > @@ -39,18 +41,13 @@ static int adc128_adc_conversion(struct adc128 *adc, u8 channel) > msg[0] = channel << 3; > msg[1] = 0; > > - mutex_lock(&adc->lock); > + guard(mutex)(&adc->lock); As per earlier comment, I think you need to protect msg as well. > > ret = spi_write(adc->spi, msg, 2); > - if (ret < 0) { > - mutex_unlock(&adc->lock); > + if (ret < 0) > return ret; > - } > > ret = spi_read(adc->spi, &adc->buffer, 2); > - > - mutex_unlock(&adc->lock); > - > if (ret < 0) > return ret; >