diff options
author | Enric Balletbo i Serra <enric.balletbo@collabora.com> | 2018-07-16 12:25:47 +0200 |
---|---|---|
committer | Felipe Balbi <felipe.balbi@linux.intel.com> | 2018-07-26 14:01:50 +0300 |
commit | 76251db8656194d27629300c852b53c471e9b586 (patch) | |
tree | 00fc8f191444444efb5d214e7351454a10c93958 | |
parent | 1fcba97e35696b7cc5662fe704ada540b49f5601 (diff) | |
download | linux-76251db8656194d27629300c852b53c471e9b586.tar.bz2 |
usb: dwc3: of-simple: reset host controller at suspend/resume
If we power off the SoC logic rail in S3, we can find that the Type-C
PHY can't initialize correctly after system resume. We need to toggle
the USB3-OTG reset before trying to initialize the PHY, or else it
times out.
phy phy-ff800000.phy.9: phy poweron failed --> -110
dwc3 fe900000.dwc3: failed to initialize core
dwc3: probe of fe900000.dwc3 failed with error -110
Note that the RK3399 TRM suggests that we should keep the whole usb3
controller in reset for the duration of the Type-C PHY initialization.
However, it's hard to assert the reset in the current framework of
reset. We're still skeptical about that, and we haven't yet found a
case where this seems to have mattered. This approach is much easier, it
simply holds the USB3-OTG reset while device is supended.
The dwc3 core is going to reinitialize the controller at suspend/resume
anyway (including a "soft reset"), so it should be safe to do this.
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
-rw-r--r-- | drivers/usb/dwc3/dwc3-of-simple.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/drivers/usb/dwc3/dwc3-of-simple.c b/drivers/usb/dwc3/dwc3-of-simple.c index dbeff5e6ad14..40bf9e0bbc59 100644 --- a/drivers/usb/dwc3/dwc3-of-simple.c +++ b/drivers/usb/dwc3/dwc3-of-simple.c @@ -28,6 +28,7 @@ struct dwc3_of_simple { int num_clocks; struct reset_control *resets; bool pulse_resets; + bool need_reset; }; static int dwc3_of_simple_clk_init(struct dwc3_of_simple *simple, int count) @@ -93,6 +94,13 @@ static int dwc3_of_simple_probe(struct platform_device *pdev) platform_set_drvdata(pdev, simple); simple->dev = dev; + /* + * Some controllers need to toggle the usb3-otg reset before trying to + * initialize the PHY, otherwise the PHY times out. + */ + if (of_device_is_compatible(np, "rockchip,rk3399-dwc3")) + simple->need_reset = true; + if (of_device_is_compatible(np, "amlogic,meson-axg-dwc3") || of_device_is_compatible(np, "amlogic,meson-gxl-dwc3")) { shared_resets = true; @@ -201,9 +209,30 @@ static int dwc3_of_simple_runtime_resume(struct device *dev) return 0; } + +static int dwc3_of_simple_suspend(struct device *dev) +{ + struct dwc3_of_simple *simple = dev_get_drvdata(dev); + + if (simple->need_reset) + reset_control_assert(simple->resets); + + return 0; +} + +static int dwc3_of_simple_resume(struct device *dev) +{ + struct dwc3_of_simple *simple = dev_get_drvdata(dev); + + if (simple->need_reset) + reset_control_deassert(simple->resets); + + return 0; +} #endif static const struct dev_pm_ops dwc3_of_simple_dev_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(dwc3_of_simple_suspend, dwc3_of_simple_resume) SET_RUNTIME_PM_OPS(dwc3_of_simple_runtime_suspend, dwc3_of_simple_runtime_resume, NULL) }; |