tree 16110e03e52da0e70221aea78f50dff581145ae2
parent 89c18f106c0812796f36464934b478005a097f53
author Steinar H. Gunderson <sesse@google.com> 1464113595 +0200
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1468254674 -0700

usb: dwc3: exynos: Fix deferred probing storm.

commit 4879efb34f7d49235fac334d76d9c6a77a021413 upstream.

dwc3-exynos has two problems during init if the regulators are slow
to come up (for instance if the I2C bus driver is not on the initramfs)
and return probe deferral. First, every time this happens, the driver
leaks the USB phys created; they need to be deallocated on error.

Second, since the phy devices are created before the regulators fail,
this means that there's a new device to re-trigger deferred probing,
which causes it to essentially go into a busy loop of re-probing the
device until the regulators come up.

Move the phy creation to after the regulators have succeeded, and also
fix cleanup on failure. On my ODROID XU4 system (with Debian's initramfs
which doesn't contain the I2C driver), this reduces the number of probe
attempts (for each of the two controllers) from more than 2000 to eight.

Signed-off-by: Steinar H. Gunderson <sesse@google.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Vivek Gautam <gautam.vivek@samsung.com>
Fixes: d720f057fda4 ("usb: dwc3: exynos: add nop transceiver support")
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>