diff options
| author |   Roger Quadros <rogerq@ti.com> | 2017-10-31 15:11:55 +0200 |
|---|---|---|
| committer |   Felipe Balbi <felipe.balbi@linux.intel.com> | 2017-12-11 12:36:53 +0200 |
| commit | 42bf02ec6e420e541af9a47437d0bdf961ca2972 (patch) | |
| tree | d26f219a5d67aad75da1ec0db2e7a71fe0164352 /drivers/usb/dwc3/core.h | |
| parent | USB: dummy-hcd: Adapt dummy_udc_set_speed() (diff) | |
| download | wireguard-linux-42bf02ec6e420e541af9a47437d0bdf961ca2972.tar.xz wireguard-linux-42bf02ec6e420e541af9a47437d0bdf961ca2972.zip | |
usb: dwc3: Allow disabling of metastability workaround
Some platforms (e.g. TI's DRA7 USB2 instance) have more trouble
with the metastability workaround as it supports only
a High-Speed PHY and the PHY can enter into an Erratic state [1]
when the controller is set in SuperSpeed mode as part of
the metastability workaround.
This causes upto 2 seconds delay in enumeration on DRA7's USB2
instance in gadget mode.
If these platforms can be better off without the workaround,
provide a device tree property to suggest that so the workaround
is avoided.
[1] Device mode enumeration trace showing PHY Erratic Error.
irq/90-dwc3-969 [000] d... 52.323145: dwc3_event: event (00000901): Erratic Error [U0]
irq/90-dwc3-969 [000] d... 52.560646: dwc3_event: event (00000901): Erratic Error [U0]
irq/90-dwc3-969 [000] d... 52.798144: dwc3_event: event (00000901): Erratic Error [U0]
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Diffstat (limited to 'drivers/usb/dwc3/core.h')
| -rw-r--r-- | drivers/usb/dwc3/core.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h index be60d797f3ee..03c7aaaac926 100644 --- a/drivers/usb/dwc3/core.h +++ b/drivers/usb/dwc3/core.h @@ -856,6 +856,7 @@ struct dwc3_scratchpad_array { * 1 - -3.5dB de-emphasis * 2 - No de-emphasis * 3 - Reserved + * @dis_metastability_quirk: set to disable metastability quirk. * @imod_interval: set the interrupt moderation interval in 250ns * increments or 0 to disable. */ @@ -1008,6 +1009,8 @@ struct dwc3 { unsigned tx_de_emphasis_quirk:1; unsigned tx_de_emphasis:2; + unsigned dis_metastability_quirk:1; + u16 imod_interval; }; |