hte: tegra194: don't access struct gpio_chip

Using struct gpio_chip is not safe as it will disappear if the
underlying driver is unbound for any reason. Switch to using reference
counted struct gpio_device and its dedicated accessors.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Tested-by: Dipen Patel <dipenp@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
[andy: used gpio_device_find_by_fwnode()]
Reviewed-by: Dipen Patel <dipenp@nvidia.com>
Link: https://lore.kernel.org/r/20231010151709.4104747-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

hte: tegra194: Switch to LATE_SIMPLE_DEV_PM_OPS()

SET_LATE_SYSTEM_SLEEP_PM_OPS is deprecated, replace it with
LATE_SYSTEM_SLEEP_PM_OPS() and use pm_sleep_ptr() for setting
the driver's pm routines. We can now remove the __maybe_unused
qualifier in the suspend and resume functions.

Tested-by: Dipen Patel <dipenp@nvidia.com>
Reviewed-by: Dipen Patel <dipenp@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20231010151709.4104747-5-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dipen Patel <dipenp@nvidia.com>

hte: tegra194: Remove redundant dev_err()

There is no need to call the dev_err() function directly to print a custom
message when handling an error from platform_get_irq() function as it is
going to display an appropriate error message in case of a failure.

Reviewed-by: Dipen Patel <dipenp@nvidia.com>
Tested-by: Dipen Patel <dipenp@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20231010151709.4104747-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dipen Patel <dipenp@nvidia.com>

hte: tegra194: improve the GPIO-related comment

Using any of the GPIO interfaces using the global numberspace is
deprecated. Make it clear in the comment.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Dipen Patel <dipenp@nvidia.com>
Signed-off-by: Dipen Patel <dipenp@nvidia.com>

hte: Explicitly include correct DT includes

The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it was merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Acked-by: Dipen Patel <dipenp@nvidia.com>
Link: https://lore.kernel.org/r/20230714174600.4057041-1-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>

hte: tegra-194: Fix off by one in tegra_hte_map_to_line_id()

The "map_sz" is the number of elements in the "m" array so the >
comparison needs to be changed to >= to prevent an out of bounds
read.

Fixes: 09574cca6ad6 ("hte: Add Tegra194 HTE kernel provider")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Acked-by: Dipen Patel <dipenp@nvidia.com>
Signed-off-by: Dipen Patel <dipenp@nvidia.com>

hte: handle nvidia,gpio-controller property

The dt binding adds nvidia,gpio-controller property from Tegra234 SoC
onwards to simplify code handling gpio chip search. The gpio chip search
is needed for the AON GPIO GTE instances to map the hardware timestamp
GPIO request (coming from the GPIO framework) to the tegra HTE
providers. The patch also adds new gpio chip match function to match
from the fwnode instead of the gpio controller label. The addition
of the property does not break ABI for the existing Tegra194 code.

Signed-off-by: Dipen Patel <dipenp@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

hte: Deprecate nvidia,slices property

The relevant DT bindings deprecates nvidia,slices property from
Tegra234 SoC onwards, moving the slices value per SoC data structure
instead.

Signed-off-by: Dipen Patel <dipenp@nvidia.com>

hte: Add Tegra234 provider

The Tegra234 AON GPIO instance and LIC IRQ support HTE. For the GPIO
HTE support, it also requires to add mapping between GPIO and HTE
framework same as it was done with Tegra194 SoC.

Signed-off-by: Dipen Patel <dipenp@nvidia.com>

hte: Add Tegra194 HTE kernel provider

Tegra194 device has multiple HTE instances also known as GTE (Generic
Hardware Timestamping Engine) which can timestamp subset of SoC lines
and signals. This provider driver focuses on IRQ and GPIO lines and
exposes timestamping ability on those lines to the consumers through
HTE subsystem.

Also, with this patch, added:
- documentation about this provider and its capabilities at
Documentation/hte.
- Compilation support in Makefile and Kconfig

Signed-off-by: Dipen Patel <dipenp@nvidia.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>