On Tue, Mar 18, 2025, Bjorn Andersson wrote:
> When the core is integrated with glue, it's reasonable to assume that
> the glue driver will have to touch the IP before/after the core takes
> the hardware out and into reset. As such the glue must own these
> resources and be allowed to turn them on/off outside the core's
> handling.
>
> Allow the platform or glue layer to indicate if the core logic for
> clocks and resets should be skipped to deal with this.
>
> Reviewed-by: Frank Li <Frank.Li@xxxxxxx>
> Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxxxxxxxx>
> ---
> drivers/usb/dwc3/core.c | 20 +++++++++++---------
> drivers/usb/dwc3/glue.h | 3 +++
> 2 files changed, 14 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index b428b6fc3d0a55811e2f75d33d79df4b0c67dcac..77a9848a0ac70fbe563988cecbe489130989aadc 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -2198,15 +2198,17 @@ int dwc3_core_probe(const struct dwc3_probe_data *data)
> if (IS_ERR(dwc->usb_psy))
> return dev_err_probe(dev, PTR_ERR(dwc->usb_psy), "couldn't get usb power supply\n");
>
> - dwc->reset = devm_reset_control_array_get_optional_shared(dev);
> - if (IS_ERR(dwc->reset)) {
> - ret = PTR_ERR(dwc->reset);
> - goto err_put_psy;
> - }
> + if (!data->ignore_clocks_and_resets) {
> + dwc->reset = devm_reset_control_array_get_optional_shared(dev);
> + if (IS_ERR(dwc->reset)) {
> + ret = PTR_ERR(dwc->reset);
> + goto err_put_psy;
> + }
>
> - ret = dwc3_get_clocks(dwc);
> - if (ret)
> - goto err_put_psy;
> + ret = dwc3_get_clocks(dwc);
> + if (ret)
> + goto err_put_psy;
> + }
>
> ret = reset_control_deassert(dwc->reset);
> if (ret)
> @@ -2321,7 +2323,7 @@ EXPORT_SYMBOL_GPL(dwc3_core_probe);
>
> static int dwc3_probe(struct platform_device *pdev)
> {
> - struct dwc3_probe_data probe_data;
> + struct dwc3_probe_data probe_data = {};
> struct resource *res;
> struct dwc3 *dwc;
>
> diff --git a/drivers/usb/dwc3/glue.h b/drivers/usb/dwc3/glue.h
> index e73cfc466012f07214291abe56454934ab014013..703d40c189565b1e28ae28afb8728b78f4cd2fca 100644
> --- a/drivers/usb/dwc3/glue.h
> +++ b/drivers/usb/dwc3/glue.h
> @@ -13,10 +13,13 @@
> * dwc3_probe_data: Initialization parameters passed to dwc3_core_probe()
> * @dwc: Reference to dwc3 context structure
> * @res: resource for the DWC3 core mmio region
> + * @ignore_clocks_and_resets: clocks and resets defined for the device should
> + * be ignored by the DWC3 core, as they are managed by the glue
> */
> struct dwc3_probe_data {
> struct dwc3 *dwc;
> struct resource *res;
> + bool ignore_clocks_and_resets;
> };
>
> int dwc3_core_probe(const struct dwc3_probe_data *data);
>
> --
> 2.48.1
>
Acked-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>
Thanks,
Thinh
