Antti, On Thu, Nov 19, 2015 at 1:09 PM, Antti Seppälä <a.seppala@xxxxxxxxx> wrote: > On 19 November 2015 at 21:45, Douglas Anderson <dianders@xxxxxxxxxxxx> wrote: >> In general it is wise to clear interrupts before processing them. If >> you don't do that, you can get: >> 1. Interrupt happens >> 2. You look at system state and process interrupt >> 3. A new interrupt happens >> 4. You clear interrupt without processing it. >> >> This patch was actually a first attempt to fix missing device insertions >> as described in (usb: dwc2: host: Fix missing device insertions) and it >> did solve some of the signal bouncing problems but not all of >> them (which is why I submitted the other patch). Specifically, this >> patch itself would sometimes change: >> 1. hardware sees connect >> 2. hardware sees disconnect >> 3. hardware sees connect >> 4. dwc2_port_intr() - clears connect interrupt >> 5. dwc2_handle_common_intr() - calls dwc2_hcd_disconnect() >> >> ...to: >> 1. hardware sees connect >> 2. hardware sees disconnect >> 3. dwc2_port_intr() - clears connect interrupt >> 4. hardware sees connect >> 5. dwc2_handle_common_intr() - calls dwc2_hcd_disconnect() >> >> ...but with different timing then sometimes we'd still miss cable >> insertions. >> >> In any case, though this patch doesn't fix any (known) problems, it >> still seems wise as a general policy to clear interrupt before handling >> them. >> >> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx> >> Acked-by: John Youn <johnyoun@xxxxxxxxxxxx> >> Tested-by: John Youn <johnyoun@xxxxxxxxxxxx> >> --- >> Changes in v3: >> - Don't (uselessly) clear the PRTINT anymore (Felipe Balbi). >> >> Changes in v2: None >> > > Hi. > > It seems that towards the end of hcd_intr.c you seem to be switching a > few calls of dwc2_writel() to plain writel(). It looks like something > that is easily overlooked but please always use dwc2_writel to > preserve correct register endianness on big-endian platforms. Oops! That was a very dumb oversight, thanks for catching. Sorry about that. Fix coming. -Doug -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
