From: Wayne Chang <waynec@nvidia.com>
To: Vinod Koul <vkoul@kernel.org>, JC Kuo <jckuo@nvidia.com>,
Thierry Reding <thierry.reding@kernel.org>,
Jonathan Hunter <jonathanh@nvidia.com>,
"Neil Armstrong" <neil.armstrong@linaro.org>,
Manivannan Sadhasivam <mani@kernel.org>,
Rob Herring <robh@kernel.org>,
Krzysztof Kozlowski <krzk+dt@kernel.org>,
Conor Dooley <conor+dt@kernel.org>
Cc: <linux-phy@lists.infradead.org>, <devicetree@vger.kernel.org>,
<linux-tegra@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
Wayne Chang <waynec@nvidia.com>
Subject: [PATCH V3 1/4] dt-bindings: phy: tegra-xusb: Add support for Tegra264
Date: Thu, 3 Sep 2026 15:19:34 +0800 [thread overview]
Message-ID: <20260903071937.533646-2-waynec@nvidia.com> (raw)
In-Reply-To: <20260903071937.533646-1-waynec@nvidia.com>
Add the compatible string for the Tegra264 XUSB PHY.
A dedicated compatible string is used instead of falling back to
nvidia,tegra234-xusb-padctl, because Tegra264 is not
programming-compatible with Tegra234, even though they share the same
DT property set. The driver selects per-SoC data from the compatible
string, and Tegra264 differs from Tegra234 in at least:
- Tegra264 uses hardware tracking mode (trk_hw_mode), while Tegra234
disables it.
- On Tegra234, CYA_TRK_CODE_UPDATE_ON_IDLE needs to be cleared so that
the calibration values can be captured while the controller is
still in reset. Tegra264 does not require this, and the
corresponding handling is not even present for it.
A fallback of nvidia,tegra234-xusb-padctl would let an OS that only
knows about Tegra234 probe Tegra264 with the wrong programming
sequence. This is also why Tegra234 did not fall back to
nvidia,tegra194-xusb-padctl in this same binding: the DT schema is
shared, but each generation needs its own compatible.
Signed-off-by: Wayne Chang <waynec@nvidia.com>
---
V2 -> V3: Add rationale to the commit message for why Tegra264 does
not use a fallback compatible, per Krzysztof's and Conor's review.
V1 -> V2: No change
.../devicetree/bindings/phy/nvidia,tegra194-xusb-padctl.yaml | 1 +
1 file changed, 1 insertion(+)
diff --git a/Documentation/devicetree/bindings/phy/nvidia,tegra194-xusb-padctl.yaml b/Documentation/devicetree/bindings/phy/nvidia,tegra194-xusb-padctl.yaml
index d8de900a4fce..f6fe3c90b5b0 100644
--- a/Documentation/devicetree/bindings/phy/nvidia,tegra194-xusb-padctl.yaml
+++ b/Documentation/devicetree/bindings/phy/nvidia,tegra194-xusb-padctl.yaml
@@ -45,6 +45,7 @@ properties:
enum:
- nvidia,tegra194-xusb-padctl
- nvidia,tegra234-xusb-padctl
+ - nvidia,tegra264-xusb-padctl
reg:
items:
--
2.25.1
--
linux-phy mailing list
linux-phy@lists.infradead.org
https://lists.infradead.org/mailman/listinfo/linux-phy
next prev parent reply other threads:[~2026-09-03 7:20 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-03 7:19 [PATCH V3 0/4] phy: tegra: xusb: Add Tegra264 support Wayne Chang
2026-09-03 7:19 ` Wayne Chang [this message]
2026-09-03 17:34 ` [PATCH V3 1/4] dt-bindings: phy: tegra-xusb: Add support for Tegra264 Conor Dooley
2026-09-03 7:19 ` [PATCH V3 2/4] phy: tegra: xusb: Use devm_clk_get_optional to fetch USB2 tracking clock Wayne Chang
2026-09-03 7:32 ` sashiko-bot
2026-09-03 7:19 ` [PATCH V3 3/4] phy: tegra: xusb: Increase timeout for USB2_TRK_COMPLETED polling Wayne Chang
2026-09-03 7:19 ` [PATCH V3 4/4] phy: tegra: xusb: Add Tegra264 support Wayne Chang
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20260903071937.533646-2-waynec@nvidia.com \
--to=waynec@nvidia.com \
--cc=conor+dt@kernel.org \
--cc=devicetree@vger.kernel.org \
--cc=jckuo@nvidia.com \
--cc=jonathanh@nvidia.com \
--cc=krzk+dt@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-phy@lists.infradead.org \
--cc=linux-tegra@vger.kernel.org \
--cc=mani@kernel.org \
--cc=neil.armstrong@linaro.org \
--cc=robh@kernel.org \
--cc=thierry.reding@kernel.org \
--cc=vkoul@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox