Re: [PATCH v2 2/2] Revert "usb: dwc3: Don't switch OTG -> peripheral if extcon is present"

From: Ferry Toth <fntoth@gmail.com>
To: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: Thinh Nguyen <Thinh.Nguyen@synopsys.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	"linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Felipe Balbi <balbi@kernel.org>,
	"stable@vger.kernel.org" <stable@vger.kernel.org>
Subject: Re: [PATCH v2 2/2] Revert "usb: dwc3: Don't switch OTG -> peripheral if extcon is present"
Date: Thu, 13 Oct 2022 21:35:42 +0200	[thread overview]
Message-ID: <bec17559-286c-b006-476f-3c26ae38e70d@gmail.com> (raw)
In-Reply-To: <CAHQ1cqF_FvG0G2CAQooOVR3E442ApNFf8EKK8PpxcOrUoL5jDA@mail.gmail.com>

<SNIP>
> My end goal here is to find a way to test vanilla v6.0 with the two
> patches reverted on your end. I thought that during my testing I saw
> tusb1210 print those timeout messages during its probe and that
> disabling the driver worked to break the loop, but I went back to
> double check and it doesn't work so scratch that idea. Configuring
> extcon as a built-in breaks host functionality with or without patches
> on my end, so I'm not sure it could be a path.
>
> I won't have time to try things with
> 0043b-TODO-driver-core-Break-infinite-loop-when-deferred-p.patch until
> the weekend, meanwhile can you give this diff a try with vanilla (no
> reverts) v6.0:
>
> modified   drivers/phy/ti/phy-tusb1210.c
> @@ -127,6 +127,7 @@ static int tusb1210_set_mode(struct phy *phy, enum
> phy_mode mode, int submode)
>    u8 reg;
>
>    ret = tusb1210_ulpi_read(tusb, ULPI_OTG_CTRL, &reg);
> + WARN_ON(ret < 0);
>    if (ret < 0)
>    return ret;
>
> @@ -152,7 +153,10 @@ static int tusb1210_set_mode(struct phy *phy,
> enum phy_mode mode, int submode)
>    }
>
>    tusb->otg_ctrl = reg;
> - return tusb1210_ulpi_write(tusb, ULPI_OTG_CTRL, reg);
> + ret = tusb1210_ulpi_write(tusb, ULPI_OTG_CTRL, reg);
> + WARN_ON(ret < 0);
> + return ret;
> +
>   }
>
>   #ifdef CONFIG_POWER_SUPPLY
>
> ? I'm curious to see if there's masked errors on your end since dwc3
> driver doesn't check for those.
root@yuna:~# dmesg | grep -i -E 'warn|assert|error|tusb|dwc3'
8250_mid: probe of 0000:00:04.0 failed with error -16
platform regulatory.0: Direct firmware load for regulatory.db failed 
with error -2
brcmfmac mmc2:0001:1: Direct firmware load for 
brcm/brcmfmac43340-sdio.Intel Corporation-Merrifield.bin failed with 
error -2
sof-audio-pci-intel-tng 0000:00:0d.0: error: I/O region is too small.
sof-audio-pci-intel-tng 0000:00:0d.0: error: failed to probe DSP -19


>> This is done through configfs only when the switch is set to device mode.
> Sure, but can it be disabled? We are looking for unknown variables, so
> excluding this would be a reasonable thing to do.
It's not enabled until I flip the switch to device mode.