linux/drivers/usb/dwc2
Douglas Anderson 4e50e0110c usb: dwc2: host: Use periodic interrupt even with DMA
The old code in dwc2_process_periodic_channels() would only enable the
"periodic empty" interrupt if we weren't using DMA.  That wasn't right
since we can still get into cases where we have small FIFOs even on
systems that have DMA (the rk3288 is a prime example).

Let's always enable/disable the "periodic empty" when appropriate.  As
part of this:

* Always call dwc2_process_periodic_channels() even if there's nothing
  in periodic_sched_assigned (we move the queue empty check so we still
  avoid the extra work).  That will make extra certain that we will
  properly disable the "periodic empty" interrupt even if there's
  nothing queued up.

* Move the enable of "periodic empty" due to non-empty
  periodic_sched_assigned to be for slave mode (non-DMA mode) only.
  Presumably this was the original intention of the check for DMA since
  it seems to match the comments above where in slave mode we leave
  things on the assigned queue.

Note that even before this change slave mode didn't work for me, so I
can't say for sure that my understanding of slave mode is correct.
However, this shouldn't change anything for slave mode so if slave mode
worked for someone in the past it ought to still work.

With this change, I no longer get constant misses reported by my other
debugging code (and with future patches) when I've got:
* Rockchip rk3288 Chromebook, using port ff540000
  -> Pluggable 7-port Hub with Charging (powered)
     -> Microsoft Wireless Keyboard 2000 in port 1.
     -> Das Keyboard in port 2.
     -> Jabra Speaker in port 3
     -> Logitech, Inc. Webcam C600 in port 4
     -> Microsoft Sidewinder X6 Keyboard in port 5

...and I'm playing music on the USB speaker and capturing video from the
webcam.

Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
2016-03-04 15:14:42 +02:00
..
core_intr.c usb: dwc2: host: Clear interrupts before handling them 2015-12-15 09:12:41 -06:00
core.c usb: dwc2: host: Properly set the HFIR 2016-03-04 15:14:42 +02:00
core.h usb: dwc2: host: Add scheduler tracing 2016-03-04 15:14:41 +02:00
debug.h usb: dwc2: move debugfs code to a separate file 2015-04-29 15:18:25 -05:00
debugfs.c usb: dwc2: Use platform endianness when accessing registers 2015-09-27 10:54:31 -05:00
gadget.c usb: dwc2: gadget: Repair DSTS register decoding 2015-12-22 12:03:05 -06:00
hcd_ddma.c usb: dwc2: host: Always add to the tail of queues 2016-03-04 15:14:40 +02:00
hcd_intr.c usb: dwc2: host: There's not really a TT for the root hub 2016-03-04 15:14:42 +02:00
hcd_queue.c usb: dwc2: host: Add a delay before releasing periodic bandwidth 2016-03-04 15:14:41 +02:00
hcd.c usb: dwc2: host: Use periodic interrupt even with DMA 2016-03-04 15:14:42 +02:00
hcd.h usb: dwc2: host: Add a delay before releasing periodic bandwidth 2016-03-04 15:14:41 +02:00
hw.h usb: dwc2: host: fix descriptor list address masking 2015-12-15 09:12:41 -06:00
Kconfig usb: dwc2: USB_DWC2 should depend on HAS_DMA 2016-02-20 20:23:02 -08:00
Makefile usb: dwc2: remove dwc2_platform.ko 2015-04-29 15:20:11 -05:00
pci.c usb: dwc2: pci: Add device mode to the dwc2-pci driver 2015-03-11 15:08:17 -05:00
platform.c usb: dwc2: host: Set host_rx_fifo_size to 525 for rk3066 2016-03-04 15:14:39 +02:00