Re: FAILED: patch "[PATCH] usb: dwc3: core: Fix system suspend on TI AM62 platforms" failed to apply to 5.10-stable tree

[Roger Quadros <rogerq@kernel.org>]

Hi Greg,

Patch was marked for 6.9+ but I added a 'v' in the tag and that's probably why it
was attempted for earlier trees.

> Cc: stable@vger.kernel.org # v6.9+

cheers,
-roger

On 21/10/2024 10:52, gregkh@linuxfoundation.org wrote:
> 
> The patch below does not apply to the 5.10-stable tree.
> If someone wants it applied there, or to any other stable or longterm
> tree, then please email the backport, including the original git commit
> id to <stable@vger.kernel.org>.
> 
> To reproduce the conflict and resubmit, you may use the following commands:
> 
> git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
> git checkout FETCH_HEAD
> git cherry-pick -x 705e3ce37bccdf2ed6f848356ff355f480d51a91
> # <resolve conflicts, build, test, etc.>
> git commit -s
> git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2024102152-salvage-pursuable-3b7c@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
> 
> Possible dependencies:
> 
> 
> 
> thanks,
> 
> greg k-h
> 
> ------------------ original commit in Linus's tree ------------------
> 
> From 705e3ce37bccdf2ed6f848356ff355f480d51a91 Mon Sep 17 00:00:00 2001
> From: Roger Quadros <rogerq@kernel.org>
> Date: Fri, 11 Oct 2024 13:53:24 +0300
> Subject: [PATCH] usb: dwc3: core: Fix system suspend on TI AM62 platforms
> 
> Since commit 6d735722063a ("usb: dwc3: core: Prevent phy suspend during init"),
> system suspend is broken on AM62 TI platforms.
> 
> Before that commit, both DWC3_GUSB3PIPECTL_SUSPHY and DWC3_GUSB2PHYCFG_SUSPHY
> bits (hence forth called 2 SUSPHY bits) were being set during core
> initialization and even during core re-initialization after a system
> suspend/resume.
> 
> These bits are required to be set for system suspend/resume to work correctly
> on AM62 platforms.
> 
> Since that commit, the 2 SUSPHY bits are not set for DEVICE/OTG mode if gadget
> driver is not loaded and started.
> For Host mode, the 2 SUSPHY bits are set before the first system suspend but
> get cleared at system resume during core re-init and are never set again.
> 
> This patch resovles these two issues by ensuring the 2 SUSPHY bits are set
> before system suspend and restored to the original state during system resume.
> 
> Cc: stable@vger.kernel.org # v6.9+
> Fixes: 6d735722063a ("usb: dwc3: core: Prevent phy suspend during init")
> Link: https://lore.kernel.org/all/1519dbe7-73b6-4afc-bfe3-23f4f75d772f@kernel.org/
> Signed-off-by: Roger Quadros <rogerq@kernel.org>
> Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
> Tested-by: Markus Schneider-Pargmann <msp@baylibre.com>
> Reviewed-by: Dhruva Gole <d-gole@ti.com>
> Link: https://lore.kernel.org/r/20241011-am62-lpm-usb-v3-1-562d445625b5@kernel.org
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> 
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 21740e2b8f07..427e5660f87c 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -2342,6 +2342,11 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
>  	u32 reg;
>  	int i;
>  
> +	dwc->susphy_state = (dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0)) &
> +			    DWC3_GUSB2PHYCFG_SUSPHY) ||
> +			    (dwc3_readl(dwc->regs, DWC3_GUSB3PIPECTL(0)) &
> +			    DWC3_GUSB3PIPECTL_SUSPHY);
> +
>  	switch (dwc->current_dr_role) {
>  	case DWC3_GCTL_PRTCAP_DEVICE:
>  		if (pm_runtime_suspended(dwc->dev))
> @@ -2393,6 +2398,15 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
>  		break;
>  	}
>  
> +	if (!PMSG_IS_AUTO(msg)) {
> +		/*
> +		 * TI AM62 platform requires SUSPHY to be
> +		 * enabled for system suspend to work.
> +		 */
> +		if (!dwc->susphy_state)
> +			dwc3_enable_susphy(dwc, true);
> +	}
> +
>  	return 0;
>  }
>  
> @@ -2460,6 +2474,11 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg)
>  		break;
>  	}
>  
> +	if (!PMSG_IS_AUTO(msg)) {
> +		/* restore SUSPHY state to that before system suspend. */
> +		dwc3_enable_susphy(dwc, dwc->susphy_state);
> +	}
> +
>  	return 0;
>  }
>  
> diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> index 9c508e0c5cdf..eab81dfdcc35 100644
> --- a/drivers/usb/dwc3/core.h
> +++ b/drivers/usb/dwc3/core.h
> @@ -1150,6 +1150,8 @@ struct dwc3_scratchpad_array {
>   * @sys_wakeup: set if the device may do system wakeup.
>   * @wakeup_configured: set if the device is configured for remote wakeup.
>   * @suspended: set to track suspend event due to U3/L2.
> + * @susphy_state: state of DWC3_GUSB2PHYCFG_SUSPHY + DWC3_GUSB3PIPECTL_SUSPHY
> + *		  before PM suspend.
>   * @imod_interval: set the interrupt moderation interval in 250ns
>   *			increments or 0 to disable.
>   * @max_cfg_eps: current max number of IN eps used across all USB configs.
> @@ -1382,6 +1384,7 @@ struct dwc3 {
>  	unsigned		sys_wakeup:1;
>  	unsigned		wakeup_configured:1;
>  	unsigned		suspended:1;
> +	unsigned		susphy_state:1;
>  
>  	u16			imod_interval;
>  
>