linux_dsm_epyc7002/drivers/usb/dwc2
Douglas Anderson 29539019b4 usb: dwc2: host: Clear interrupts before handling them
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.

Note that for dwc2_handle_usb_port_intr(), instead of moving the clear
of PRTINT to the beginning of the function we remove it completely.  The
only way to clear PRTINT is to clear the sources that set it in the
first place.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2015-12-15 09:12:41 -06:00
..
core_intr.c usb: dwc2: host: Clear interrupts before handling them 2015-12-15 09:12:41 -06:00
core.c usb: dwc2: host: Support immediate retries for split transactions 2015-12-15 09:12:41 -06:00
core.h usb: dwc2: host: Fix missing device insertions 2015-12-15 09:12:41 -06:00
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: refactor common low-level hw code to platform.c 2015-10-14 08:40:15 -05:00
hcd_ddma.c usb: dwc2: host: use kmem cache to allocate descriptors 2015-12-15 09:12:41 -06:00
hcd_intr.c usb: dwc2: host: Clear interrupts before handling them 2015-12-15 09:12:41 -06:00
hcd_queue.c usb: dwc2: host: enable descriptor dma for fs devices 2015-12-15 09:12:41 -06:00
hcd.c usb: dwc2: host: Add missing spinlock in dwc2_hcd_reset_func() 2015-12-15 09:12:41 -06:00
hcd.h usb: dwc2: host: avoid usage of dma_alloc_coherent with irqs disabled 2015-12-15 09:12:41 -06:00
hw.h usb: dwc2: host: fix descriptor list address masking 2015-12-15 09:12:41 -06:00
Kconfig usb: dwc2: remove dwc2_platform.ko 2015-04-29 15:20:11 -05:00
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: add support of hi6220 2015-12-15 09:12:41 -06:00