Re: [U-Boot] [U-Boot, v3, 6/7] USB: usb-hub: Add a weak function for resetting devices
Hi Dan, guys,
Just would like to give my 5 cents: my humble experience with OMAP4 and OMAP5 tells me that this (that is, the need to reset devices after applying port power) seems to be a OMAP5 HSIC IP issue, and not a device problem. We at MMS have two custom designs, one with OMAP5430 and one with OMAP4460, both of which employ HSIC chips (LAN9730 and USB4640 on the OMAP5 board, and USB4640 on the OMAP4), along with a ULPI PHY (TUSB1210) on both boards. I had the pleasure of bringing up both boards with U-Boot a few months back, including USB EHCI, and can state the following:
Device reset after port power is applied is needed for the OMAP5 HSIC devices only. The ULPI PHY on both boards doesn't even have a hardware reset connected, nevertheless the device attached to it gets enumerated (even without performing PHY software reset via the ULPI viewport). I performed the HSIC device reset by calling a board function from within the ehci_hcd.c driver, which is compiled only for the OMAP5, and only if we have HSIC devices. An obsolete patch for this, working on my board, can still be found at http://patchwork.ozlabs.org/patch/232742/, as well as a RFC for the 5432uevm (untested) at http://patchwork.ozlabs.org/patch/244124/
On the OMAP4 board this reset is not needed, the HSIC device gets enumerated straightforward.
I don't know about other arches, but I'm not sure that having an unconditional common call, although weak, in usb_hub.c is the best solution.
Best regards, Lubo
Lubo
Thanks for the reply
On 07/25/2013 03:38 PM, Lubomir Popov wrote:
Hi Dan, guys,
Just would like to give my 5 cents: my humble experience with OMAP4 and OMAP5 tells me that this (that is, the need to reset devices after applying port power) seems to be a OMAP5 HSIC IP issue, and not a device problem. We at MMS have two custom designs, one with OMAP5430 and one with OMAP4460, both of which employ HSIC chips (LAN9730 and USB4640 on the OMAP5 board, and USB4640 on the OMAP4), along with a ULPI PHY (TUSB1210) on both boards. I had the pleasure of bringing up both boards with U-Boot a few months back, including USB EHCI, and can state the following:
Device reset after port power is applied is needed for the OMAP5 HSIC devices only. The ULPI PHY on both boards doesn't even have a hardware reset connected, nevertheless the device attached to it gets enumerated (even without performing PHY software reset via the ULPI viewport). I performed the HSIC device reset by calling a board function from within the ehci_hcd.c driver, which is compiled only for the OMAP5, and only if we have HSIC devices. An obsolete patch for this, working on my board, can still be found at http://patchwork.ozlabs.org/patch/232742/, as well as a RFC for the 5432uevm (untested) at http://patchwork.ozlabs.org/patch/244124/
On the OMAP4 board this reset is not needed, the HSIC device gets enumerated straightforward.
I don't know about other arches, but I'm not sure that having an unconditional common call, although weak, in usb_hub.c is the best solution.
Best regards, Lubo
I see your patches and see that you have added a omap5 specific call to reset the device in the ehci-hcd.c.
I originally had a similar implementation in ehci-hcd but decided to move it up to the usb-hub. http://patchwork.ozlabs.org/patch/258229/
But I can move it back since the patch exists.
This make it all board specific because as you point out it is only needed in HSIC connection
Crazy question was there any support documentation for the OMAP5 HSIC issue?
Dan
Dear Dan Murphy,
Lubo
Thanks for the reply
On 07/25/2013 03:38 PM, Lubomir Popov wrote:
Hi Dan, guys,
Just would like to give my 5 cents: my humble experience with OMAP4 and OMAP5 tells me that this (that is, the need to reset devices after applying port power) seems to be a OMAP5 HSIC IP issue, and not a device problem. We at MMS have two custom designs, one with OMAP5430 and one with OMAP4460, both of which employ HSIC chips (LAN9730 and USB4640 on the OMAP5 board, and USB4640 on the OMAP4), along with a ULPI PHY (TUSB1210) on both boards. I had the pleasure of bringing up both boards with U-Boot a few months back, including USB EHCI, and can state the following:
Device reset after port power is applied is needed for the OMAP5 HSIC devices only. The ULPI PHY on both boards doesn't even have a hardware reset connected, nevertheless the device attached to it gets enumerated (even without performing PHY software reset via the ULPI viewport). I performed the HSIC device reset by calling a board function from within the ehci_hcd.c driver, which is compiled only for the OMAP5, and only if we have HSIC devices. An obsolete patch for this, working on my board, can still be found at http://patchwork.ozlabs.org/patch/232742/, as well as a RFC for the 5432uevm (untested) at http://patchwork.ozlabs.org/patch/244124/
On the OMAP4 board this reset is not needed, the HSIC device gets enumerated straightforward.
I don't know about other arches, but I'm not sure that having an unconditional common call, although weak, in usb_hub.c is the best solution.
Best regards, Lubo
I see your patches and see that you have added a omap5 specific call to reset the device in the ehci-hcd.c.
I originally had a similar implementation in ehci-hcd but decided to move it up to the usb-hub. http://patchwork.ozlabs.org/patch/258229/
But I can move it back since the patch exists.
This make it all board specific because as you point out it is only needed in HSIC connection
Crazy question was there any support documentation for the OMAP5 HSIC issue?
Nice to see this is moving in some well-defined direction.
Best regards, Marek Vasut
Hi Dan,
On 26/07/13 03:30, Dan Murphy wrote:
Lubo
Thanks for the reply
On 07/25/2013 03:38 PM, Lubomir Popov wrote:
Hi Dan, guys,
Just would like to give my 5 cents: my humble experience with OMAP4 and OMAP5 tells me that this (that is, the need to reset devices after applying port power) seems to be a OMAP5 HSIC IP issue, and not a device problem. We at MMS have two custom designs, one with OMAP5430 and one with OMAP4460, both of which employ HSIC chips (LAN9730 and USB4640 on the OMAP5 board, and USB4640 on the OMAP4), along with a ULPI PHY (TUSB1210) on both boards. I had the pleasure of bringing up both boards with U-Boot a few months back, including USB EHCI, and can state the following:
Device reset after port power is applied is needed for the OMAP5 HSIC devices only. The ULPI PHY on both boards doesn't even have a hardware reset connected, nevertheless the device attached to it gets enumerated (even without performing PHY software reset via the ULPI viewport). I performed the HSIC device reset by calling a board function from within the ehci_hcd.c driver, which is compiled only for the OMAP5, and only if we have HSIC devices. An obsolete patch for this, working on my board, can still be found at http://patchwork.ozlabs.org/patch/232742/, as well as a RFC for the 5432uevm (untested) at http://patchwork.ozlabs.org/patch/244124/
On the OMAP4 board this reset is not needed, the HSIC device gets enumerated straightforward.
I don't know about other arches, but I'm not sure that having an unconditional common call, although weak, in usb_hub.c is the best solution.
Best regards, Lubo
I see your patches and see that you have added a omap5 specific call to reset the device in the ehci-hcd.c.
I originally had a similar implementation in ehci-hcd but decided to move it up to the usb-hub. http://patchwork.ozlabs.org/patch/258229/
But I can move it back since the patch exists.
This make it all board specific because as you point out it is only needed in HSIC connection
Crazy question was there any support documentation for the OMAP5 HSIC issue?
Well, none that I know of. Apart from the published HSIC bug (errata ID i774), which however seems unrelated to this particular issue, I'm not aware of any other documented problems. But I must admit that I'm not a TI employee anymore (my xID has expired in April) and at present don't have access to TI's internal stuff, so my info could be obsolete.
You could try to contact Jerome Angeloni j-angeloni@ti.com, if he still has the TI account active - he was the guy at TI France with most experience with OMAP USB applications. But, as you know, TIF is gone...
Dan
--
Dan Murphy
Regards, Lubo
participants (3)
-
Dan Murphy -
Lubomir Popov -
Marek Vasut