Writing a rule specific to a USB connector

Writing a rule specific to a USB connector

[Diego Iastrubni]

Hi all,

Sorry if this offtopic is this list, in such case please point me to
correct location.
I am tring to write a rule that will create a specific char device for
every different USB connector (this is an embeeded application, and
the use case is: "please connect the device to the upper connector").
I am using 173 on 2.6.32/arm.

I have two different USB controllers which can be identified by
ATTRS{serial}="musb_hdrc" and ATTRS{serial}="ehci-omap.0"


First try:

KERNEL="hidraw[0-9]*", ATTRS{serial}="musb_hdrc", SYMLINK+="aaaaaaaaaa"
KERNEL="hidraw[0-9]*", ATTRS{idVendor}="c1ca", SYMLINK+="bbbbbbbbbbb"


OK, works. I see both links generated. Now I need to combine them:

KERNEL="hidraw[0-9]*", ATTRS{idVendor}="c1ca",
ATTRS{serial}="musb_hdrc", SYMLINK+="cccccccccc"
KERNEL="hidraw[0-9]*", ATTRS{serial}="musb_hdrc",
ATTRS{idVendor}="c1ca", SYMLINK+="dddddddddd"


None working. What I think in happening is that the idVendor of the
USB hub is matched and not of the device. I need to match:

ATTR{idVendor}="c1ca" and some parent has ATTRS{serial}="musb_hdrc"


What is the golden rule I am missing?

- diego

Re: Writing a rule specific to a USB connector

[Tom Gundersen]

On Tue, Aug 23, 2011 at 10:03 AM, Diego Iastrubni <diegoiast@gmail.com> wrote:
> KERNEL="hidraw[0-9]*", ATTRS{serial}="musb_hdrc", SYMLINK+="aaaaaaaaaa"
> KERNEL="hidraw[0-9]*", ATTRS{idVendor}="c1ca", SYMLINK+="bbbbbbbbbbb"
>
>
> OK, works. I see both links generated. Now I need to combine them:
>
> KERNEL="hidraw[0-9]*", ATTRS{idVendor}="c1ca",
> ATTRS{serial}="musb_hdrc", SYMLINK+="cccccccccc"
> KERNEL="hidraw[0-9]*", ATTRS{serial}="musb_hdrc",
> ATTRS{idVendor}="c1ca", SYMLINK+="dddddddddd"

ATTRS matches on a parent device, two instances of ATTRS matches on
_the same_ parent device. In your case I guess idVendor and serial
match on different parent devices, which would explain why they work
separately but no together.

Finally you say:

> None working. What I think in happening is that the idVendor of the
> USB hub is matched and not of the device. I need to match:
>
> ATTR{idVendor}="c1ca" and some parent has ATTRS{serial}="musb_hdrc"
>
>
> What is the golden rule I am missing?

Sounds to me like you should have used:

KERNEL="hidraw[0-9]*", ATTR{idVendor}="c1ca",
ATTRS{serial}="musb_hdrc", SYMLINK+="eeeeeeeee"

Cheers,

Tom

Re: Writing a rule specific to a USB connector

[Diego Iastrubni]

On Tue, Aug 23, 2011 at 11:15 AM, Tom Gundersen <teg@jklm.no> wrote:
> ATTRS matches on a parent device, two instances of ATTRS matches on
> _the same_ parent device. In your case I guess idVendor and serial
> match on different parent devices, which would explain why they work
> separately but no together.

Eventually I found a documentation that mentions this, but in was not
easy. A very stable difference, hard to understand (now documented in
this archive!). Thanks!

> Sounds to me like you should have used:
>
> KERNEL="hidraw[0-9]*", ATTR{idVendor}="c1ca",
> ATTRS{serial}="musb_hdrc", SYMLINK+="eeeeeeeee"

KERNEL="hidraw[0-9]*", ATTR{idVendor}="c1ca",     SYMLINK+="1111111"
KERNEL="hidraw[0-9]*", ATTRS{idVendor}="c1ca",    SYMLINK+="2222222"
KERNEL="hidraw[0-9]*", ATTRS{serial}="musb_hdrc", SYMLINK+="3333333"
KERNEL="hidraw[0-9]*", ATTR{idVendor}="c1ca",
ATTRS{serial}="musb_hdrc", SYMLINK+="4444444"

[/root 10.10.10.44] $ udevadm test /sys/class/hidraw/hidraw0 2>&1 |  grep DEV
UDEV_LOG=6
DEVPATH=/devices/platform/musb_hdrc/usb1/1-1/1-1.1/1-1.1:1.0/0003:C1CA:0003.0008/hidraw/hidraw0
DEVNAME=/dev/hidraw0
DEVLINKS=/dev/2222222 /dev/3333333

[/root 10.10.10.44] $ udevadm info --query=all --name=/dev/hidraw0
--attribute-walk 2>&1 | egrep 'serial|idVendor'
    ATTRS{idVendor}="c1ca"
    ATTRS{idVendor}="05e3"
    ATTRS{idVendor}="1d6b"
    ATTRS{serial}="musb_hdrc"

I was expecting to see "11111", and I don't. This explains why
"444444" is not working. Still - something is not working here.

Re: Writing a rule specific to a USB connector

[Tom Gundersen]

On Tue, Aug 23, 2011 at 10:59 AM, Diego Iastrubni <diegoiast@gmail.com> wrote:
> KERNEL="hidraw[0-9]*", ATTR{idVendor}="c1ca",     SYMLINK+="1111111"

[...]

> [/root 10.10.10.44] $ udevadm info --query=all --name=/dev/hidraw0
> --attribute-walk 2>&1 | egrep 'serial|idVendor'
>    ATTRS{idVendor}="c1ca"
>    ATTRS{idVendor}="05e3"
>    ATTRS{idVendor}="1d6b"
>    ATTRS{serial}="musb_hdrc"
>
> I was expecting to see "11111", and I don't. This explains why
> "444444" is not working. Still - something is not working here.

I guess c1ca is not the idVendor of your hidraw device, but of one of
it its parents. Could you post the output of "udevadm info --query=all
--name=/dev/hidraw0 --attribute-walk" (without the egrep)?

-t

Re: Writing a rule specific to a USB connector

[Diego Iastrubni]

On Tue, Aug 23, 2011 at 12:51 PM, Tom Gundersen <teg@jklm.no> wrote:
> I guess c1ca is not the idVendor of your hidraw device, but of one of
> it its parents. Could you post the output of "udevadm info --query=all
> --name=/dev/hidraw0 --attribute-walk" (without the egrep)?

[/root 10.10.10.44] $ udevadm info --query=all --name=/dev/hidraw0
--attribute-walk

Udevadm info starts with the device specified by the devpath and then
walks up the chain of parent devices. It prints for every device
found, all possible attributes in the udev rules key format.
A rule to match, can be composed by the attributes of the device
and the attributes from one single parent device.

  looking at device
'/devices/platform/musb_hdrc/usb1/1-1/1-1.1/1-1.1:1.0/0003:C1CA:0003.0001/hidraw/hidraw0':
    KERNEL="hidraw0"
    SUBSYSTEM="hidraw"
    DRIVER=""

  looking at parent device
'/devices/platform/musb_hdrc/usb1/1-1/1-1.1/1-1.1:1.0/0003:C1CA:0003.0001':
    KERNELS="0003:C1CA:0003.0001"
    SUBSYSTEMS="hid"
    DRIVERS="generic-usb"

  looking at parent device
'/devices/platform/musb_hdrc/usb1/1-1/1-1.1/1-1.1:1.0':
    KERNELS="1-1.1:1.0"
    SUBSYSTEMS="usb"
    DRIVERS="usbhid"
    ATTRS{bInterfaceNumber}="00"
    ATTRS{bAlternateSetting}=" 0"
    ATTRS{bNumEndpoints}="01"
    ATTRS{bInterfaceClass}="03"
    ATTRS{bInterfaceSubClass}="00"
    ATTRS{bInterfaceProtocol}="00"
    ATTRS{supports_autosuspend}="1"
    ATTRS{interface}="BIOGOARD"

  looking at parent device '/devices/platform/musb_hdrc/usb1/1-1/1-1.1':
    KERNELS="1-1.1"
    SUBSYSTEMS="usb"
    DRIVERS="usb"
    ATTRS{configuration}="Default configuration"
    ATTRS{bNumInterfaces}=" 1"
    ATTRS{bConfigurationValue}="1"
    ATTRS{bmAttributes}="40"
    ATTRS{bMaxPower}="  0mA"
    ATTRS{urbnum}="41"
    ATTRS{idVendor}="c1ca"
    ATTRS{idProduct}="0003"
    ATTRS{bcdDevice}="0000"
    ATTRS{bDeviceClass}="00"
    ATTRS{bDeviceSubClass}="00"
    ATTRS{bDeviceProtocol}="00"
    ATTRS{bNumConfigurations}="1"
    ATTRS{bMaxPacketSize0}="8"
    ATTRS{speed}="12"
    ATTRS{busnum}="1"
    ATTRS{devnum}="3"
    ATTRS{devpath}="1.1"
    ATTRS{version}=" 1.01"
    ATTRS{maxchild}="0"
    ATTRS{quirks}="0x0"
    ATTRS{authorized}="1"
    ATTRS{manufacturer}="Sysmop tech."
    ATTRS{product}="USB PALM"

  looking at parent device '/devices/platform/musb_hdrc/usb1/1-1':
    KERNELS="1-1"
    SUBSYSTEMS="usb"
    DRIVERS="usb"
    ATTRS{configuration}=""
    ATTRS{bNumInterfaces}=" 1"
    ATTRS{bConfigurationValue}="1"
    ATTRS{bmAttributes}="e0"
    ATTRS{bMaxPower}="100mA"
    ATTRS{urbnum}="50"
    ATTRS{idVendor}="05e3"
    ATTRS{idProduct}="0608"
    ATTRS{bcdDevice}="0702"
    ATTRS{bDeviceClass}="09"
    ATTRS{bDeviceSubClass}="00"
    ATTRS{bDeviceProtocol}="01"
    ATTRS{bNumConfigurations}="1"
    ATTRS{bMaxPacketSize0}="64"
    ATTRS{speed}="480"
    ATTRS{busnum}="1"
    ATTRS{devnum}="2"
    ATTRS{devpath}="1"
    ATTRS{version}=" 2.00"
    ATTRS{maxchild}="4"
    ATTRS{quirks}="0x0"
    ATTRS{authorized}="1"
    ATTRS{product}="USB2.0 Hub"

  looking at parent device '/devices/platform/musb_hdrc/usb1':
    KERNELS="usb1"
    SUBSYSTEMS="usb"
    DRIVERS="usb"
    ATTRS{configuration}=""
    ATTRS{bNumInterfaces}=" 1"
    ATTRS{bConfigurationValue}="1"
    ATTRS{bmAttributes}="e0"
    ATTRS{bMaxPower}="  0mA"
    ATTRS{urbnum}="26"
    ATTRS{idVendor}="1d6b"
    ATTRS{idProduct}="0002"
    ATTRS{bcdDevice}="0206"
    ATTRS{bDeviceClass}="09"
    ATTRS{bDeviceSubClass}="00"
    ATTRS{bDeviceProtocol}="00"
    ATTRS{bNumConfigurations}="1"
    ATTRS{bMaxPacketSize0}="64"
    ATTRS{speed}="480"
    ATTRS{busnum}="1"
    ATTRS{devnum}="1"
    ATTRS{devpath}="0"
    ATTRS{version}=" 2.00"
    ATTRS{maxchild}="1"
    ATTRS{quirks}="0x0"
    ATTRS{authorized}="1"
    ATTRS{manufacturer}="Linux 2.6.32 musb-hcd"
    ATTRS{product}="MUSB HDRC host driver"
    ATTRS{serial}="musb_hdrc"
    ATTRS{authorized_default}="1"

  looking at parent device '/devices/platform/musb_hdrc':
    KERNELS="musb_hdrc"
    SUBSYSTEMS="platform"
    DRIVERS="musb_hdrc"
    ATTRS{mode}="a_host"
    ATTRS{vbus}="Vbus off, timeout 1100"

  looking at parent device '/devices/platform':
    KERNELS="platform"
    SUBSYSTEMS=""
    DRIVERS=""

Re: Writing a rule specific to a USB connector

[Tom Gundersen]

On Tue, Aug 23, 2011 at 12:45 PM, Diego Iastrubni <diegoiast@gmail.com> wrote:
> On Tue, Aug 23, 2011 at 12:51 PM, Tom Gundersen <teg@jklm.no> wrote:
>> I guess c1ca is not the idVendor of your hidraw device, but of one of
>> it its parents. Could you post the output of "udevadm info --query=all
>> --name=/dev/hidraw0 --attribute-walk" (without the egrep)?
>
> [/root 10.10.10.44] $ udevadm info --query=all --name=/dev/hidraw0
> --attribute-walk

[...]

>  looking at device
> '/devices/platform/musb_hdrc/usb1/1-1/1-1.1/1-1.1:1.0/0003:C1CA:0003.0001/hidraw/hidraw0':
>    KERNEL="hidraw0"
>    SUBSYSTEM="hidraw"
>    DRIVER=""

[...]

>  looking at parent device '/devices/platform/musb_hdrc/usb1/1-1/1-1.1':
>    KERNELS="1-1.1"
>    SUBSYSTEMS="usb"
>    DRIVERS="usb"
>    ATTRS{configuration}="Default configuration"
>    ATTRS{bNumInterfaces}=" 1"
>    ATTRS{bConfigurationValue}="1"
>    ATTRS{bmAttributes}="40"
>    ATTRS{bMaxPower}="  0mA"
>    ATTRS{urbnum}="41"
>    ATTRS{idVendor}="c1ca"
>    ATTRS{idProduct}="0003"
>    ATTRS{bcdDevice}="0000"
>    ATTRS{bDeviceClass}="00"
>    ATTRS{bDeviceSubClass}="00"
>    ATTRS{bDeviceProtocol}="00"
>    ATTRS{bNumConfigurations}="1"
>    ATTRS{bMaxPacketSize0}="8"
>    ATTRS{speed}="12"
>    ATTRS{busnum}="1"
>    ATTRS{devnum}="3"
>    ATTRS{devpath}="1.1"
>    ATTRS{version}=" 1.01"
>    ATTRS{maxchild}="0"
>    ATTRS{quirks}="0x0"
>    ATTRS{authorized}="1"
>    ATTRS{manufacturer}="Sysmop tech."
>    ATTRS{product}="USB PALM"

[...]

>  looking at parent device '/devices/platform/musb_hdrc/usb1':
>    KERNELS="usb1"
>    SUBSYSTEMS="usb"
>    DRIVERS="usb"
>    ATTRS{configuration}=""
>    ATTRS{bNumInterfaces}=" 1"
>    ATTRS{bConfigurationValue}="1"
>    ATTRS{bmAttributes}="e0"
>    ATTRS{bMaxPower}="  0mA"
>    ATTRS{urbnum}="26"
>    ATTRS{idVendor}="1d6b"
>    ATTRS{idProduct}="0002"
>    ATTRS{bcdDevice}="0206"
>    ATTRS{bDeviceClass}="09"
>    ATTRS{bDeviceSubClass}="00"
>    ATTRS{bDeviceProtocol}="00"
>    ATTRS{bNumConfigurations}="1"
>    ATTRS{bMaxPacketSize0}="64"
>    ATTRS{speed}="480"
>    ATTRS{busnum}="1"
>    ATTRS{devnum}="1"
>    ATTRS{devpath}="0"
>    ATTRS{version}=" 2.00"
>    ATTRS{maxchild}="1"
>    ATTRS{quirks}="0x0"
>    ATTRS{authorized}="1"
>    ATTRS{manufacturer}="Linux 2.6.32 musb-hcd"
>    ATTRS{product}="MUSB HDRC host driver"
>    ATTRS{serial}="musb_hdrc"
>    ATTRS{authorized_default}="1"

Ok, so that explains why you don't get your 11111 symlink, the
idVendor you are matching against is not on the device you want, but
on a parent.

I honestly don't know the best way to match against two different
parents, which is apparently what you need. I guess something like
this should work though:

SUBSYSTEM!="hidraw", GOTO="hidraw_end"
ATTRS{idVendor}!="c1ca", GOTO="hidraw_end"
ATTRS{serial}="musb_hdrc", SYMLINK+="444444"
LABEL="hidraw_end"

Maybe someone else knows a better solution?

Cheers,

Tom

Re: Writing a rule specific to a USB connector

[Diego Iastrubni]

On Tue, Aug 23, 2011 at 2:01 PM, Tom Gundersen <teg@jklm.no> wrote:
> Ok, so that explains why you don't get your 11111 symlink, the
> idVendor you are matching against is not on the device you want, but
> on a parent.
>
> I honestly don't know the best way to match against two different
> parents, which is apparently what you need. I guess something like
> this should work though:
>
> SUBSYSTEM!="hidraw", GOTO="hidraw_end"
> ATTRS{idVendor}!="c1ca", GOTO="hidraw_end"
> ATTRS{serial}="musb_hdrc", SYMLINK+="444444"
> LABEL="hidraw_end"

... and for some reason the code above did not work. However, this
ugly piece of code does. No idea what in wrong.


SUBSYSTEMS      = "hidraw"    , GOTO     = "blabla_1"
GOTO             = "blabla_end"

LABEL            = "blabla_1"
ATTRS{idVendor} = "c1ca"      , GOTO     = "blabla_2"
GOTO             =  "blabla_end"

LABEL            = "blabla_2"
ATTRS{serial}   = "musb_hdrc"   , SYMLINK += "blabla-upper"
ATTRS{serial}   = "ehci-omap.0" , SYMLINK += "blabla-lower"

LABEL            = "blabla_end"