Commit c31a401f authored by Claudiu Beznea's avatar Claudiu Beznea Committed by Greg Kroah-Hartman
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usb: host: ehci-platform: Call reset assert/deassert on suspend/resume 



The Renesas RZ/G3S SoC supports a power-saving mode in which power to most
of the SoC components is turned off, including the USB blocks. On the
resume path, the reset signal must be de-asserted before applying any
settings to the USB registers. To handle this properly, call
reset_control_assert() and reset_control_deassert() during suspend and
resume, respectively.

Signed-off-by: default avatarClaudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Acked-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Link: https://patch.msgid.link/20251106143625.3050119-3-claudiu.beznea.uj@bp.renesas.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent a7d5fe02

drivers/usb/host/ehci-platform.c

+20 −2
Original line number Diff line number Diff line
@@ -454,6 +454,17 @@ static int __maybe_unused ehci_platform_suspend(struct device *dev) 
	if (pdata->power_suspend)

		pdata->power_suspend(pdev);



	ret = reset_control_assert(priv->rsts);

	if (ret) {

		if (pdata->power_on)

			pdata->power_on(pdev);



		ehci_resume(hcd, false);



		if (priv->quirk_poll)

			quirk_poll_init(priv);

	}



	return ret;

}
@@ -464,12 +475,19 @@ static int __maybe_unused ehci_platform_resume(struct device *dev) 
	struct platform_device *pdev = to_platform_device(dev);

	struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);

	struct device *companion_dev;

	int err;



	err = reset_control_deassert(priv->rsts);

	if (err)

		return err;



	if (pdata->power_on) {

		int err = pdata->power_on(pdev);

		if (err < 0)

		err = pdata->power_on(pdev);

		if (err < 0) {

			reset_control_assert(priv->rsts);

			return err;

		}

	}



	companion_dev = usb_of_get_companion_dev(hcd->self.controller);

	if (companion_dev) {