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From:   Dipen Patel <dipenp@nvidia.com>
To:     <thierry.reding@gmail.com>, <jonathanh@nvidia.com>,
        <linux-kernel@vger.kernel.org>, <linux-tegra@vger.kernel.org>,
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        <krzysztof.kozlowski+dt@linaro.org>, <brgl@bgdev.pl>,
        <corbet@lwn.net>, <gregkh@linuxfoundation.org>
CC:     Dipen Patel <dipenp@nvidia.com>
Subject: [V6 5/9] hte: Re-phrase tegra API document
Date:   Thu, 13 Apr 2023 17:44:51 -0700
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Make Tegra194 API document generic to make it applicable for
current and future tegra hte providers.

Signed-off-by: Dipen Patel <dipenp@nvidia.com>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
---
v5:
- rename tegra194-hte.rst to tegra-hte.rst

 Documentation/driver-api/hte/index.rst        |  2 +-
 .../hte/{tegra194-hte.rst => tegra-hte.rst}   | 33 +++++++++----------
 2 files changed, 17 insertions(+), 18 deletions(-)
 rename Documentation/driver-api/hte/{tegra194-hte.rst => tegra-hte.rst} (50%)

diff --git a/Documentation/driver-api/hte/index.rst b/Documentation/driver-api/hte/index.rst
index 9f43301c05dc..29011de9a4b8 100644
--- a/Documentation/driver-api/hte/index.rst
+++ b/Documentation/driver-api/hte/index.rst
@@ -18,5 +18,5 @@ HTE Tegra Provider
 .. toctree::
    :maxdepth: 1
 
-   tegra194-hte
+   tegra-hte
 
diff --git a/Documentation/driver-api/hte/tegra194-hte.rst b/Documentation/driver-api/hte/tegra-hte.rst
similarity index 50%
rename from Documentation/driver-api/hte/tegra194-hte.rst
rename to Documentation/driver-api/hte/tegra-hte.rst
index f2d617265546..85e654772782 100644
--- a/Documentation/driver-api/hte/tegra194-hte.rst
+++ b/Documentation/driver-api/hte/tegra-hte.rst
@@ -5,25 +5,25 @@ HTE Kernel provider driver
 
 Description
 -----------
-The Nvidia tegra194 HTE provider driver implements two GTE
-(Generic Timestamping Engine) instances: 1) GPIO GTE and 2) LIC
-(Legacy Interrupt Controller) IRQ GTE. Both GTE instances get the
-timestamp from the system counter TSC which has 31.25MHz clock rate, and the
-driver converts clock tick rate to nanoseconds before storing it as timestamp
-value.
+The Nvidia tegra HTE provider also known as GTE (Generic Timestamping Engine)
+driver implements two GTE instances: 1) GPIO GTE and 2) LIC
+(Legacy Interrupt Controller) IRQ GTE. Both GTE instances get the timestamp
+from the system counter TSC which has 31.25MHz clock rate, and the driver
+converts clock tick rate to nanoseconds before storing it as timestamp value.
 
 GPIO GTE
 --------
 
 This GTE instance timestamps GPIO in real time. For that to happen GPIO
-needs to be configured as input. The always on (AON) GPIO controller instance
-supports timestamping GPIOs in real time and it has 39 GPIO lines. The GPIO GTE
-and AON GPIO controller are tightly coupled as it requires very specific bits
-to be set in GPIO config register before GPIO GTE can be used, for that GPIOLIB
-adds two optional APIs as below. The GPIO GTE code supports both kernel
-and userspace consumers. The kernel space consumers can directly talk to HTE
-subsystem while userspace consumers timestamp requests go through GPIOLIB CDEV
-framework to HTE subsystem.
+needs to be configured as input. Only the always on (AON) GPIO controller
+instance supports timestamping GPIOs in real time as it is tightly coupled with
+the GPIO GTE. To support this, GPIOLIB adds two optional APIs as mentioned
+below. The GPIO GTE code supports both kernel and userspace consumers. The
+kernel space consumers can directly talk to HTE subsystem while userspace
+consumers timestamp requests go through GPIOLIB CDEV framework to HTE
+subsystem. The hte devicetree binding described at
+``Documentation/devicetree/bindings/timestamp`` provides an example of how a
+consumer can request an GPIO line.
 
 See gpiod_enable_hw_timestamp_ns() and gpiod_disable_hw_timestamp_ns().
 
@@ -34,9 +34,8 @@ returns the timestamp in nanoseconds.
 LIC (Legacy Interrupt Controller) IRQ GTE
 -----------------------------------------
 
-This GTE instance timestamps LIC IRQ lines in real time. There are 352 IRQ
-lines which this instance can add timestamps to in real time. The hte
-devicetree binding described at ``Documentation/devicetree/bindings/timestamp``
+This GTE instance timestamps LIC IRQ lines in real time. The hte devicetree
+binding described at ``Documentation/devicetree/bindings/timestamp``
 provides an example of how a consumer can request an IRQ line. Since it is a
 one-to-one mapping with IRQ GTE provider, consumers can simply specify the IRQ
 number that they are interested in. There is no userspace consumer support for
-- 
2.17.1