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Subject: Re: [PATCH v6 19/23] drivers/fsi: Add GPIO based FSI master
To: Jeremy Kerr <jk@ozlabs.org>, Joel Stanley <joel@jms.id.au>
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Cc: Rob Herring <robh+dt@kernel.org>, Mark Rutland <mark.rutland@arm.com>,
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From: Christopher Bostic <cbostic@linux.vnet.ibm.com>
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On 5/10/17 8:58 PM, Jeremy Kerr wrote:
> Hi Chris,
>
>> I don't think we'd want this per master.   The lock is for the 'top'
>> master issuing commands.  Only the top master can initiate any
>> transactions on the bus to any devices connected downstream. Downstream
>> masters such as hub masters, etc... cannot initiate a command.
> I think what Joel meant there was that we have it per *GPIO* master; if
> there are two GPIO masters on a system, there's no need to provide
> mutual exclusion to each (separate) set of GPIOs.
>
> To implement this, we'd just move the lock into struct fsi_master_gpio.

Hi Jeremy,

Understand now -will make the change.

Thanks
-Chris

> Cheers,
>
>
> Jeremy
>