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Message-ID: <29521c9c-90d3-03b9-cf6f-8519efcd007e@kernel.org>
Date:   Wed, 1 Jun 2022 08:48:07 -0500
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Subject: Re: [PATCHv2 1/2] i2c: designware: introduce a custom scl recovery
 for SoCFPGA platforms
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To:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc:     jarkko.nikula@linux.intel.com, mika.westerberg@linux.intel.com,
        robh+dt@kernel.org, krzk+dt@kernel.org, linux-i2c@vger.kernel.org,
        linux-kernel@vger.kernel.org, devicetree@vger.kernel.org
References: <20220524135441.420600-1-dinguyen@kernel.org>
 <Yo0LKQchQwitJVHm@smile.fi.intel.com>
From:   Dinh Nguyen <dinguyen@kernel.org>
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On 5/24/22 11:43, Andy Shevchenko wrote:
> On Tue, May 24, 2022 at 08:54:40AM -0500, Dinh Nguyen wrote:
>> The I2C pins on the SoCFPGA platforms do not go through a GPIO module,
>> thus cannot be recovered by the default method of by doing a GPIO access.
>> Only a reset of the I2C IP block can a recovery be successful.
> 
> Better now, but see my additional comments.
> 
> ...
> 
>> +	switch (dev->flags & MODEL_MASK) {
>> +	case MODEL_SOCFPGA:
>> +		rinfo->recover_bus = i2c_socfpga_scl_recovery;
>> +		break;
>> +	default:
>> +		rinfo->recover_bus = i2c_generic_scl_recovery;
>> +		break;
>> +	}
> 
>> +	adap->bus_recovery_info = rinfo;
> 
> Usually we do not assign the pointer while data structure is incomplete.
> That's said, please leave this line as it was.
> 
> On top of that, why you can't move the above switch to the place where old
> function was assigned?
> 

The reason is the assignment of the recover_bus needs to get done before 
the call to devm_gpiod_get_optional(), otherwise, the assignment is not 
taking place because of an error after returning from 
devm_gpiod_get_optional().

Dinh