Re: [PATCH 1/1] phy: tegra: xusb: Fix UTMI AO sleepwalk trigger programming sequence
From: JC Kuo
Date: Thu Dec 04 2025 - 02:12:15 EST
Hi Wayne
On 12/3/25 10:47, Wayne Chang wrote:
> From: Haotien Hsu <haotienh@xxxxxxxxxx>
>
> The UTMIP sleepwalk programming sequence requires asserting both
> LINEVAL_WALK_EN and WAKE_WALK_EN when enabling the sleepwalk logic.
> However, the current code mistakenly cleared WAKE_WALK_EN, which
> prevents the sleepwalk trigger from operating correctly.
>
> Fix this by asserting WAKE_WALK_EN together with LINEVAL_WALK_EN.
>
> Fixes: 1f9cab6cc20c ("phy: tegra: xusb: Add wake/sleepwalk for Tegra186")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Haotien Hsu <haotienh@xxxxxxxxxx>
> Signed-off-by: Wayne Chang <waynec@xxxxxxxxxx>
> ---
> drivers/phy/tegra/xusb-tegra186.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/phy/tegra/xusb-tegra186.c b/drivers/phy/tegra/xusb-tegra186.c
> index e818f6c3980e..b2a76710c0c4 100644
> --- a/drivers/phy/tegra/xusb-tegra186.c
> +++ b/drivers/phy/tegra/xusb-tegra186.c
> @@ -401,8 +401,7 @@ static int tegra186_utmi_enable_phy_sleepwalk(struct tegra_xusb_lane *lane,
>
> /* enable the trigger of the sleepwalk logic */
> value = ao_readl(priv, XUSB_AO_UTMIP_SLEEPWALK_CFG(index));
> - value |= LINEVAL_WALK_EN;
> - value &= ~WAKE_WALK_EN;
> + value |= LINEVAL_WALK_EN | WAKE_WALK_EN;
> ao_writel(priv, value, XUSB_AO_UTMIP_SLEEPWALK_CFG(index));
>
> /* reset the walk pointer and clear the alarm of the sleepwalk logic,
WAKE_WALK_EN has to be set with '0' according to the ASIC designers. Tegra234
and Tegra239 TRMs have been updated. We will get Tegra264 document updated as well.
Thanks,
JC