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    SubjectRe: [PATCH V4 06/10] hte: Re-phrase tegra API document
    From
    On 3/23/23 08:29, Dipen Patel wrote:
    > Make Tegra194 API document generic to make it applicable for
    > current and future tegra hte providers.
    >
    > Signed-off-by: Dipen Patel <dipenp@nvidia.com>
    > ---
    > Documentation/driver-api/hte/tegra194-hte.rst | 33 +++++++++----------
    > 1 file changed, 16 insertions(+), 17 deletions(-)
    >

    While generalizing the doc, the doc file name should also be renamed
    (i.e. to tegra-hte.rst).

    > diff --git a/Documentation/driver-api/hte/tegra194-hte.rst b/Documentation/driver-api/hte/tegra194-hte.rst
    > index f2d617265546..85e654772782 100644
    > --- a/Documentation/driver-api/hte/tegra194-hte.rst
    > +++ b/Documentation/driver-api/hte/tegra194-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

    The wording LGTM, thanks!

    Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>

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