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Message-ID: <dc79de4e-4043-5448-db44-ef8f7749a376@ideasonboard.com>
Date:   Mon, 19 Jun 2023 12:00:57 +0300
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Subject: Re: [PATCH v14 18/18] media: i2c: ds90ub953: Support non-sync mode
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To:     Andy Shevchenko <andriy.shevchenko@intel.com>
Cc:     linux-media@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org,
        Luca Ceresoli <luca.ceresoli@bootlin.com>,
        Matti Vaittinen <Matti.Vaittinen@fi.rohmeurope.com>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Sakari Ailus <sakari.ailus@linux.intel.com>,
        Wolfram Sang <wsa@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Peter Rosin <peda@axentia.se>,
        Liam Girdwood <lgirdwood@gmail.com>,
        Mark Brown <broonie@kernel.org>,
        Michael Tretter <m.tretter@pengutronix.de>,
        Hans Verkuil <hverkuil@xs4all.nl>,
        Mike Pagano <mpagano@gentoo.org>,
        =?UTF-8?Q?Krzysztof_Ha=c5=82asa?= <khalasa@piap.pl>,
        Marek Vasut <marex@denx.de>,
        Satish Nagireddy <satish.nagireddy@getcruise.com>
References: <20230616135922.442979-1-tomi.valkeinen@ideasonboard.com>
 <20230616135922.442979-19-tomi.valkeinen@ideasonboard.com>
 <ZIx17WC7plfDPpmc@smile.fi.intel.com>
From:   Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
In-Reply-To: <ZIx17WC7plfDPpmc@smile.fi.intel.com>
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Precedence: bulk

On 16/06/2023 17:47, Andy Shevchenko wrote:
> On Fri, Jun 16, 2023 at 04:59:22PM +0300, Tomi Valkeinen wrote:
>> Add support for FPD-Link non-sync mode with external clock. The only
>> thing that needs to be added is the calculation for the clkout.
> 
> ...
> 
>> +	switch (priv->mode) {
>> +	case UB953_MODE_SYNC:
>> +		if (priv->hw_data->is_ub971)
>> +			return priv->plat_data->bc_rate * 160ull;
>> +		else
>> +			return priv->plat_data->bc_rate / 2 * 160ull;
> 
> Redundant 'else'.

True, but I like the symmetry in:

if (foo)
	return 123;
else
	return 321;

> Do I understand correctly you don't want to fallthrough because it will give
> ±160 in the rate (depending if it's even or odd)?

Sorry, can you clarify? Fallthrough to what?

>> +	case UB953_MODE_NONSYNC_EXT:
>> +		/* CLKIN_DIV = 1 always */
>> +		return clk_get_rate(priv->clkin) * 80ull;
>> +
>> +	default:
>>   		/* Not supported */
>>   		return 0;
>>   	}
>