Hi Jun Li,
On Wed, May 08, 2019 at 10:52:37AM +0000, Jun Li wrote:
> From: Jun Li <jun.li@xxxxxxx>
>
> Register access in core validation may hang before the bulk
> clks are enabled.
This patch fixes the hang issue for on my i.MX8MQ based system.
Tested-by: Baruch Siach <baruch@xxxxxxxxxx>
However, commit b873e2d0ea1e is meant to move dwc3_core_is_valid() before
dwc3_get_dr_mode(). With this patch dwc3_get_dr_mode() is called from
dwc3_get_properties() before dwc3_core_is_valid().
I guess we need a larger change in the initialization sequence.
Thanks,
baruch
> Fixes: b873e2d0ea1e ("usb: dwc3: Do core validation early on probe")
> Signed-off-by: Jun Li <jun.li@xxxxxxx>
> ---
>
> Change for v2:
> - Update ret to be -ENODEV in case dwc3_core_is_valid() fail.
>
> drivers/usb/dwc3/core.c | 13 +++++++------
> 1 file changed, 7 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 4aff1d8..93b96e6 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -1423,11 +1423,6 @@ static int dwc3_probe(struct platform_device *pdev)
> dwc->regs = regs;
> dwc->regs_size = resource_size(&dwc_res);
>
> - if (!dwc3_core_is_valid(dwc)) {
> - dev_err(dwc->dev, "this is not a DesignWare USB3 DRD Core\n");
> - return -ENODEV;
> - }
> -
> dwc3_get_properties(dwc);
>
> dwc->reset = devm_reset_control_get_optional_shared(dev, NULL);
> @@ -1460,6 +1455,12 @@ static int dwc3_probe(struct platform_device *pdev)
> if (ret)
> goto unprepare_clks;
>
> + if (!dwc3_core_is_valid(dwc)) {
> + dev_err(dwc->dev, "this is not a DesignWare USB3 DRD Core\n");
> + ret = -ENODEV;
> + goto disable_clks;
> + }
> +
> platform_set_drvdata(pdev, dwc);
> dwc3_cache_hwparams(dwc);
>
> @@ -1524,7 +1525,7 @@ static int dwc3_probe(struct platform_device *pdev)
> err1:
> pm_runtime_put_sync(&pdev->dev);
> pm_runtime_disable(&pdev->dev);
> -
> +disable_clks:
> clk_bulk_disable(dwc->num_clks, dwc->clks);
> unprepare_clks:
> clk_bulk_unprepare(dwc->num_clks, dwc->clks);
--
http://baruch.siach.name/blog/ ~. .~ Tk Open Systems
=}------------------------------------------------ooO--U--Ooo------------{=
- baruch@xxxxxxxxxx - tel: +972.52.368.4656, http://www.tkos.co.il -
