linux-kernel - Re: PATCH: rtsx_pci driver - don't disable the rts5229 card reader on Intel NUC boxes

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Date:   Wed, 5 Aug 2020 06:51:39 +0100
From:   Chris Clayton <chris2553@...glemail.com>
To:     吳昊澄 Ricky <ricky_wu@...ltek.com>,
        "gregkh@...uxfoundation.org" <gregkh@...uxfoundation.org>
Cc:     LKML <linux-kernel@...r.kernel.org>,
        "rdunlap@...radead.org" <rdunlap@...radead.org>,
        "philquadra@...il.com" <philquadra@...il.com>,
        Arnd Bergmann <arnd@...db.de>
Subject: Re: PATCH: rtsx_pci driver - don't disable the rts5229 card reader on
 Intel NUC boxes

Thanks, Ricky.

On 05/08/2020 03:35, 吳昊澄 Ricky wrote:
> 
> 
>> -----Original Message-----
>> From: Chris Clayton [mailto:chris2553@...glemail.com]
>> Sent: Tuesday, August 04, 2020 7:52 PM
>> To: 吳昊澄 Ricky; gregkh@...uxfoundation.org
>> Cc: LKML; rdunlap@...radead.org; philquadra@...il.com; Arnd Bergmann
>> Subject: Re: PATCH: rtsx_pci driver - don't disable the rts5229 card reader on
>> Intel NUC boxes
>>
>>
>>
>> On 04/08/2020 11:46, 吳昊澄 Ricky wrote:
>>>> -----Original Message-----
>>>> From: Chris Clayton [mailto:chris2553@...glemail.com]
>>>> Sent: Tuesday, August 04, 2020 4:51 PM
>>>> To: 吳昊澄 Ricky; gregkh@...uxfoundation.org
>>>> Cc: LKML; rdunlap@...radead.org; philquadra@...il.com; Arnd Bergmann
>>>> Subject: Re: PATCH: rtsx_pci driver - don't disable the rts5229 card reader on
>>>> Intel NUC boxes
>>>>
>>>>
>>>>
>>>> On 04/08/2020 09:08, 吳昊澄 Ricky wrote:
>>>>>> -----Original Message-----
>>>>>> From: gregkh@...uxfoundation.org [mailto:gregkh@...uxfoundation.org]
>>>>>> Sent: Tuesday, August 04, 2020 3:49 PM
>>>>>> To: 吳昊澄 Ricky
>>>>>> Cc: Chris Clayton; LKML; rdunlap@...radead.org; philquadra@...il.com;
>>>> Arnd
>>>>>> Bergmann
>>>>>> Subject: Re: PATCH: rtsx_pci driver - don't disable the rts5229 card reader
>> on
>>>>>> Intel NUC boxes
>>>>>>
>>>>>> On Tue, Aug 04, 2020 at 02:44:41AM +0000, 吳昊澄 Ricky wrote:
>>>>>>> Hi Chris,
>>>>>>>
>>>>>>> rtsx_pci_write_register(pcr, FPDTL, OC_POWER_DOWN,
>>>> OC_POWER_DOWN);
>>>>>>> This register operation saved power under 1mA, so if do not care the 1mA
>>>>>> power we can have a patch to remove it, make compatible with NUC6
>>>>>>> We tested others our card reader that remove it, we did not see any side
>>>> effect
>>>>>>>
>>>>>>> Hi Greg k-h,
>>>>>>>
>>>>>>> Do you have any comments?
>>>>>>
>>>>>> comments on what?  I don't know what you are responding to here, sorry.
>>>>>>
>>>>> Can we have a patch to kernel for NUC6? It may cause more power(1mA) but
>> it
>>>> will have more compatibility
>>>>>
>>>>
>>>> Ricky,
>>>>
>>>> I don't understand why you want to completely remove the code that sets up
>> the
>>>> 1mA power saving. That code was there
>>>> even before your patch (bede03a579b3b4a036003c4862cc1baa4ddc351f), so I
>>>> assume it benefits some of the Realtek card
>>>> readers. Before your patch however, rtsx_pci_init_ocp() was not called for the
>>>> rts5229 reader, but the patch introduced
>>>> an unconditional call to that function into rtsx_pci_init_hw(), which is run for
>> the
>>>> rts5229. That is what now disables
>>>> the card reader.
>>>>
>>>> Now, I don't know whether other cards are affected, although I don't recall
>>>> seeing any reported as I searched the kernel
>>>> and ubuntu bugzillas for any analysis of the problem. I know this is not what
>> the
>>>> patch I sent does, but having thought
>>>> about it more, seems to me that the simplest fix is to skip the new call to
>>>> rtsx_pci_init_ocp() if the reader is an rts5229.
>>>>
>>>
>>> Because we are thinking about if others our card reader that not belong A
>> series(my ocp patch coverage) also on NUC6 platform maybe have the same
>> problem...
>>>
>>
>> OK. What if we do make the new call but only for the card readers that are in the
>> A series? Are they the ones that have
>> PID_5nnn defines in include/linux/rtsx_pci.h? Or is there another simple way of
>> identifying that a reader is a member of
>> the A series?
>>
>> I'm thinking of something like:
>> static bool rtsx_pci_is_series_A(pcr)
>> {
>> 	unsigned short device = pcr->pci->device;
>>
>> 	return device == PID524A || device == PID_5249 || device == PID_5250 ||
>> device == PID_525A
>> 			|| device == PID_525A || device == PID_5260 || device ==
>> PID_5261;
>> }
>>
>> then in rtsx_pci_init_hw() change the unconditional call to:
>>
>> 	if rtsx_pci_is_series_A(pcr)
>> 		rtsx_pci_init_ocp();
>>
>> Does that seem OK?
>>
> Previously, I want to remove
> else {
> 		/* OC power down */
> 		rtsx_pci_write_register(pcr, FPDCTL, OC_POWER_DOWN,
> 			OC_POWER_DOWN);
> }
> Because in our A-series card Reader we already assigned option->ocp_en to 1 in self init_params() , this is an easy way to fix this problem
> 

Ah, OK. I'll prepare the patch and send it to you once I've tested it.

Chris