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Date:   Wed, 23 Mar 2022 10:41:23 +0100
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From:   Krzysztof Kozlowski <krzk@kernel.org>
Subject: Re: [PATCH v1 1/4] usb: host: export symbols for xhci hooks usage
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To:     Jung Daehwan <dh10.jung@samsung.com>
Cc:     Mathias Nyman <mathias.nyman@intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "open list:USB XHCI DRIVER" <linux-usb@vger.kernel.org>,
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        "chihhao . chen" <chihhao.chen@mediatek.com>, sc.suh@samsung.com,
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On 23/03/2022 03:58, Jung Daehwan wrote:
> On Mon, Mar 07, 2022 at 10:59:06AM +0100, Krzysztof Kozlowski wrote:
>> On 04/03/2022 07:23, Daehwan Jung wrote:
>>> Export symbols for xhci hooks usage:
>>> 	xhci_ring_free
>>> 	- Allow xhci hook to free xhci_ring.
>>
>> Instead of copying-pasting the name of function, please explain why do
>> you need these symbols exported.
>>
>> The "Why" is actually one of most important questions, because "what is
>> this patch doing" we can easily see...
>>
>>>
>>> 	xhci_get_slot_ctx
>>> 	- Allow xhci hook to get slot_ctx from the xhci_container_ctx
>>> 	  for getting the slot_ctx information to know which slot is
>>> 	  offloading and compare the context in remote subsystem memory
>>> 	  if needed.
>>>
>>
>>
>> Best regards,
>> Krzysztof
>>
> 
> Hi Krzysztof
> 
> xhci_ring_free has been removed from v3..
> The reason why I want to export is for managing vendor specific ring.
> I want to alloc and free vendor specific ring on specific address.
> It's done with xhci hooks.

It's better, but still does not explain why these have to be exported.
Please mention where are these hooks going to be. Where are they
implemented. I actually expect all of these exports to be used in your
patchset.

Best regards,
Krzysztof