[PATCHv4 2/2] phy: exynos5-usbdrd: Calibrate LOS levels for exynos5420/5800

Felipe Balbi balbi at kernel.org
Wed Oct 25 05:46:52 PDT 2017


Hi,

Kishon Vijay Abraham I <kishon at ti.com> writes:
> Felipe,
>
> On Monday 09 October 2017 05:30 PM, Andrzej Pietrasiewicz wrote:
>> From: Vivek Gautam <gautam.vivek at samsung.com>
>> 
>> Adding phy calibration sequence for USB 3.0 DRD PHY present on
>> Exynos5420/5800 systems.
>> This calibration facilitates setting certain PHY parameters viz.
>> the Loss-of-Signal (LOS) Detector Threshold Level, as well as
>> Tx-Vboost-Level for Super-Speed operations.
>> Additionally we also set proper time to wait for RxDetect measurement,
>> for desired PHY reference clock, so as to solve issue with enumeration
>> of few USB 3.0 devices, like Samsung SUM-TSB16S 3.0 USB drive
>> on the controller.
>> 
>> We are using CR_port for this purpose to send required data
>> to override the LOS values.
>> 
>> On testing with USB 3.0 devices on USB 3.0 port present on
>> SMDK5420, and peach-pit boards should see following message:
>> usb 2-1: new SuperSpeed USB device number 2 using xhci-hcd
>> 
>> and without this patch, should see below shown message:
>> usb 1-1: new high-speed USB device number 2 using xhci-hcd
>> 
>> [Also removed unnecessary extra lines in the register macro definitions]
>> 
>> Signed-off-by: Vivek Gautam <gautam.vivek at samsung.com>
>> [adapted to use phy_calibrate as entry point]
>> Signed-off-by: Andrzej Pietrasiewicz <andrzej.p at samsung.com>
>> ---
>>  drivers/phy/samsung/phy-exynos5-usbdrd.c | 183 +++++++++++++++++++++++++++++++
>>  drivers/usb/dwc3/core.c                  |   7 +-
>
> are you okay with this patch?

if the API is fine for you, I'm okay with it being called from dwc3
core:

Acked-by: Felipe Balbi <felipe.balbi at linux.intel.com>

-- 
balbi
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