[PATCH v2] usb: xhci: allow imod-interval to be configurable

Adam Wallis awallis at codeaurora.org
Fri Dec 1 07:50:58 PST 2017


Hi Chunfeng,

On 11/30/2017 10:32 PM, Chunfeng Yun wrote:
> Hi,
> On Wed, 2017-11-29 at 10:52 -0500, Adam Wallis wrote:
>> The xHCI driver currently has the IMOD set to 160, which
>> translates to an IMOD interval of 40,000ns (160 * 250)ns
>>
>> Commit 0cbd4b34cda9 ("xhci: mediatek: support MTK xHCI host controller")
>> introduced a QUIRK for the MTK platform to adjust this interval to 20,
[..]
>>  #include "xhci-mvebu.h"
>>  #include "xhci-rcar.h"
>> +#include "xhci-mtk.h"
> Needn't it, MTK makes use of xhci-mtk.c but not xhci-plat.c
> 

Thanks - I made this change in V3.

[..]
>>  
>>  static struct hc_driver __read_mostly xhci_plat_hc_driver;
>>  
>> @@ -269,6 +270,18 @@ static int xhci_plat_probe(struct platform_device *pdev)
>>  	if (device_property_read_bool(&pdev->dev, "quirk-broken-port-ped"))
>>  		xhci->quirks |= XHCI_BROKEN_PORT_PED;
>>  
>> +	/*
>> +	 * imod_interval is the interrupt modulation value in nanoseconds.
>> +	 * The increment interval is 8 times as much as that defined in
>> +	 * the xHCI spec on MTK's controller. This quirk check exists to provide
>> +	 * backwards compatibility, however, this should be pushed into
>> +	 * the device tree files at some point in the future and
>> +	 * checking the quirk should be removed from xhci_plat_probe.
>> +	 */
>> +	xhci->imod_interval = xhci->quirks & XHCI_MTK_HOST ? 5000 : 40000;
> Can be moved into xhci-mtk.c for MTK quirk, like as following:
> 

I moved this into V3 as suggested - could you test on an MTK platform (I don't
have one available) to see if it performs as expected?




-- 
Adam Wallis
Qualcomm Datacenter Technologies as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project.



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