Re: [PATCH v2 2/4] dmaengine: Add STM32 MDMA driver

From: Vinod Koul <vinod.koul@intel.com>
To: Pierre Yves MORDRET <pierre-yves.mordret@st.com>
Cc: Rob Herring <robh+dt@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Maxime Coquelin <mcoquelin.stm32@gmail.com>,
	Alexandre TORGUE <alexandre.torgue@st.com>,
	Russell King <linux@armlinux.org.uk>,
	Dan Williams <dan.j.williams@intel.com>,
	"M'boumba Cedric Madianga" <cedric.madianga@gmail.com>,
	Fabrice GASNIER <fabrice.gasnier@st.com>,
	Herbert Xu <herbert@gondor.apana.org.au>,
	Fabien DESSENNE <fabien.dessenne@st.com>,
	Amelie DELAUNAY <amelie.delaunay@st.com>,
	"dmaengine@vger.kernel.org" <dmaengine@vger.kernel.org>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2 2/4] dmaengine: Add STM32 MDMA driver
Date: Wed, 26 Jul 2017 10:30:07 +0530	[thread overview]
Message-ID: <20170726050007.GE3053@localhost> (raw)
In-Reply-To: <320f8def-19a4-0491-e879-b41815889e15@st.com>

On Mon, Jul 24, 2017 at 09:34:18AM +0000, Pierre Yves MORDRET wrote:
> 
> On 07/21/2017 12:32 PM, Pierre Yves MORDRET wrote:
>  >
>  >
>  > On 07/21/2017 11:54 AM, Vinod Koul wrote:
>  >> On Fri, Jul 21, 2017 at 09:30:00AM +0000, Pierre Yves MORDRET wrote:
>  >>>>> +static enum dma_slave_buswidth stm32_mdma_get_max_width(u32 buf_len, u32 
> tlen)
>  >>>>> +{
>  >>>>> +	enum dma_slave_buswidth max_width = DMA_SLAVE_BUSWIDTH_8_BYTES;
>  >>>>> +
>  >>>>> +	while (((buf_len % max_width) || (tlen < max_width)) &&
>  >>>>> +	       (max_width > DMA_SLAVE_BUSWIDTH_1_BYTE))
>  >>>>> +		max_width = max_width >> 1;
>  >>>>
>  >>>> ok, this is a bit hard to read...
>  >>>
>  >>> This code snippet has already been reworked and optimized. Would you mind to
>  >>> provide me a example with your expectation ? Thanks
>  >>
>  >> Code is optimized yes, but readable no
>  >>
>  >> I would like readability to be improved upon...
>  >>
>  >
>  > gotcha
>  >
> 
> Doest he code snippet below has a better looking for you ?
> 
> 	for (max_width = DMA_SLAVE_BUSWIDTH_8_BYTES;
> 	     max_width > DMA_SLAVE_BUSWIDTH_1_BYTE; max_width >>= 1)
> 		if (((buf_len % max_width) == 0) && (tlen >= max_width))
> 			break;

Am actually not sure :(

Indentation wise it is still a bit messy to follow..

How about:

	for (max_width = DMA_SLAVE_BUSWIDTH_8_BYTES;
			max_width > DMA_SLAVE_BUSWIDTH_1_BYTE;
			max_width >>=1) {
		if (((buf_len % max_width) == 0) && (tlen >= max_width))
			break;
	}

Thanks
-- 
~Vinod