topic Find USBPHY_CTRL Resistor in kernel tree ? in i.MX Processors

Find USBPHY_CTRL Resistor in kernel tree ?

jaymind — Thu, 05 Mar 2015 05:10:17 GMT

Hello,

I have custom board with i.MX6Q used and in which UTMI PHY2 used for USB connection to FTDI FT2232H IC.

So for setting and configuration I want to verify below registers,

USBPHY_CTRL

and want to check these 2 bits ENUTMILEVEL3 and ENUTMILEVEL2, whether it set or not.

So please suggest me that where can I find these USBPHY_CRTL reg. in which file or in which directory in kernel tree. ?

I search it in drivers->usb->core->driver.c, arch->arm->mach-max6->usb_h2.c but I didn't find any significance or clue related to that register.

Any one can suggest me about this.

Thanks in advance

Regards

Jaymin D

Re: Find USBPHY_CTRL Resistor in kernel tree ?

igorpadykov — Fri, 06 Mar 2015 00:48:20 GMT

Hi Jaymin

these bits may be set automatically by driver and used for

low speed devices, FT2232H does not support low speed.

http://www.ftdichip.com/Support/Documents/DataSheets/ICs/DS_FT2232H.pdf

Best regards

igor

-----------------------------------------------------------------------------------------------------------------------

Note: If this post answers your question, please click the Correct Answer button. Thank you!

-----------------------------------------------------------------------------------------------------------------------

Re: Find USBPHY_CTRL Resistor in kernel tree ?

jaymind — Mon, 09 Mar 2015 05:10:02 GMT

Dear Igorpadykov,

Thanks for reply, it will help me.

But can you please specify me that which driver set these bits ?

I mean which driver USB driver of i.MX6Q or FTDI FT2232H usb driver. ? :smileyconfused:

If you explain related to this topic in little more then it will surely benefit me.

Regards

Jaymin D

Re: Re: Find USBPHY_CTRL Resistor in kernel tree ?

igorpadykov — Mon, 09 Mar 2015 05:22:35 GMT

Hi Jaymin

please look at attached document

Chapter 41 CHIPIDEA USB Driver

it describes i.MX6 linux usb driver.

Best regards

igor

Re: Re: Find USBPHY_CTRL Resistor in kernel tree ?

jaymind — Mon, 09 Mar 2015 09:37:24 GMT

Dear Igorpadykov,

Thanks for help,

Its helpful me lot.

Finally I founded these 2 bits in file name as "reg-usbphy-mx6.h" in

/arch/arm/plat-mxc/include/mach/

directory in kernel tree.

and their usage founded in file "usb_h1.c" in

/arch/arm/mach-mx6/

directory in kernel tree.

I founded that they are set. :smileyhappy:

Bit no. 14 for UTMI level 3(0x8000) and bit no. 15 for UTMI level 2(0x4000)

Thank you for your share.

Regards

Jaymin D