diff options
| author | Douglas Anderson <dianders@chromium.org> | 2019-04-17 00:53:49 +0300 |
|---|---|---|
| committer | Felipe Balbi <felipe.balbi@linux.intel.com> | 2019-05-03 09:13:47 +0300 |
| commit | c40cf7705e13d288d900e044c0a2f756e9e4909a (patch) | |
| tree | 31ab9133f03c69cda3587744766a8ce59a72eddb /drivers/usb/dwc2/hcd.c | |
| parent | cc389eaabd7082a14e46aaa5a02f87c9eef37d7f (diff) | |
| download | linux-c40cf7705e13d288d900e044c0a2f756e9e4909a.tar.xz | |
usb: dwc2: optionally assert phy reset when waking up
On the rk3288 USB host-only port (the one that's not the OTG-enabled
port) the PHY can get into a bad state when a wakeup is asserted (not
just a wakeup from full system suspend but also a wakeup from
autosuspend).
We can get the PHY out of its bad state by asserting its "port reset",
but unfortunately that seems to assert a reset onto the USB bus so it
could confuse things if we don't actually deenumerate / reenumerate the
device.
We can also get the PHY out of its bad state by fully resetting it using
the reset from the CRU (clock reset unit), which does a more full
reset. The CRU-based reset appears to actually cause devices on the bus
to be removed and reinserted, which fixes the problem (albeit in a hacky
way).
It's unfortunate that we need to do a full re-enumeration of devices at
wakeup time, but this is better than alternative of letting the bus get
wedged.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Yunzhi Li <lyz@rock-chips.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Diffstat (limited to 'drivers/usb/dwc2/hcd.c')
| -rw-r--r-- | drivers/usb/dwc2/hcd.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c index 8667ddf3ca74..978232a9e4a8 100644 --- a/drivers/usb/dwc2/hcd.c +++ b/drivers/usb/dwc2/hcd.c @@ -4376,6 +4376,17 @@ static void dwc2_hcd_reset_func(struct work_struct *work) spin_unlock_irqrestore(&hsotg->lock, flags); } +static void dwc2_hcd_phy_reset_func(struct work_struct *work) +{ + struct dwc2_hsotg *hsotg = container_of(work, struct dwc2_hsotg, + phy_reset_work); + int ret; + + ret = phy_reset(hsotg->phy); + if (ret) + dev_warn(hsotg->dev, "PHY reset failed\n"); +} + /* * ========================================================================= * Linux HC Driver Functions @@ -5152,6 +5163,8 @@ static void dwc2_hcd_free(struct dwc2_hsotg *hsotg) destroy_workqueue(hsotg->wq_otg); } + cancel_work_sync(&hsotg->phy_reset_work); + del_timer(&hsotg->wkp_timer); } @@ -5293,11 +5306,10 @@ int dwc2_hcd_init(struct dwc2_hsotg *hsotg) hsotg->hc_ptr_array[i] = channel; } - /* Initialize hsotg start work */ + /* Initialize work */ INIT_DELAYED_WORK(&hsotg->start_work, dwc2_hcd_start_func); - - /* Initialize port reset work */ INIT_DELAYED_WORK(&hsotg->reset_work, dwc2_hcd_reset_func); + INIT_WORK(&hsotg->phy_reset_work, dwc2_hcd_phy_reset_func); /* * Allocate space for storing data on status transactions. Normally no |