Hi Jingoo, Yeah, I followed that discussion back then, but it seems to have stalled a little (at least the HSIC patches haven't been picked up in any kernel.org repo yet to my knowledge). The problem is that I think these approaches cannot work reliably. I agree that it would be nice to control the HSIC device from its own driver, and have spent quite some time playing around with the usb/misc/usb3503.c driver to try to make this work... but there's a timing dependency here that you just can't model correctly with independent drivers. If the HSIC device is already active during boot (e.g. because it was used by firmware), there's always a chance that the USB stack will come up before the driver that resets it does. The device will be enumerated as normal, and when the other driver later pulls the reset signal the USB stack will not notice because there is no real disconnect detection on HSIC. Only when you eventually try to send another transfer to the device will you start to get timeouts, and the newly reset device will not be able to reenumerate because the host never asks it to. I really don't see how you could solve this without putting some kind of synchronization mechanism in the USB drivers. So this leaves ehci-s5p and phy-samsung-usb2 as the only possible places, and I chose the latter since all the host-side HSIC initialization is also there already. I think if you think of it as "reset whatever is on the other side of this PHY", it's okay to put it as an optional feature into the PHY driver. -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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