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Subject: Re: [PATCH v3 03/13] bus/fsl-mc: add support for 'driver_override' in
 the mc-bus
To:     Andrew Lunn <andrew@lunn.ch>, Diana Craciun <diana.craciun@nxp.com>
Cc:     linux-kernel@vger.kernel.org, laurentiu.tudor@nxp.com,
        gregkh@linuxfoundation.org, stuyoder@gmail.com, leoyang.li@nxp.com,
        bharatb.linux@gmail.com, Bharat Bhushan <Bharat.Bhushan@nxp.com>,
        linux-arm-kernel@lists.infradead.org
References: <20200706124243.10697-1-diana.craciun@nxp.com>
 <20200706124243.10697-4-diana.craciun@nxp.com>
 <20200706135717.GB919533@lunn.ch>
From:   Diana Craciun OSS <diana.craciun@oss.nxp.com>
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Date:   Mon, 6 Jul 2020 19:35:50 +0300
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Hi Andrew,

I apologize, I somehow missed you previous comment.

OK, I see that there are a number of drivers using the same code. In 
case we share the code, probably we need to store the driver_override 
value in the struct device (not in the particular driver device 
structure as it is done now).

Diana


On 7/6/2020 4:57 PM, Andrew Lunn wrote:
> Hi Diana
>
> On Mon, Jul 06, 2020 at 03:42:33PM +0300, Diana Craciun wrote:
>> From: Bharat Bhushan <Bharat.Bhushan@nxp.com>
>>
>> This patch is required for vfio-fsl-mc meta driver to successfully bind
>> layerscape container devices for device passthrough. This patch adds
>> a mechanism to allow a layerscape device to specify a driver rather than
>> a layerscape driver provide a device match.
>>
>> Example to allow a device (dprc.1) to specifically bind
>> with driver (vfio-fsl-mc):-
>>   - echo vfio-fsl-mc > /sys/bus/fsl-mc/devices/dprc.1/driver_override
>>   - echo dprc.1 > /sys/bus/fsl-mc/drivers/fsl_mc_dprc/unbind
>>   - echo dprc.1 > /sys/bus/fsl-mc/drivers/vfio-fsl-mc/bind
> Something i asked before, why is this buried in a driver, when it
> could be put in the driver core. This is not the only driver doing
> this, so it does make sense to share the code and bugs.
>
>        Andrew