counter: microchip-tcb-capture: Fix the use of internal GCLK logic

As per the datasheet, the clock selection Bits 2:0 – TCCLKS[2:0] should
be set to 0 while using the internal GCLK (TIMER_CLOCK1).

Fixes: 106b104137fd ("counter: Add microchip TCB capture counter")
Signed-off-by: Dharma Balasubiramani <dharma.b@microchip.com>
Link: https://lore.kernel.org/r/20230905100835.315024-1-dharma.b@microchip.com
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>

counter: 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 as 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.

Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230714174357.4053541-1-robh@kernel.org/
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>

counter: microchip-tcb-capture: Handle Signal1 read and Synapse

The signal_read(), action_read(), and action_write() callbacks have been
assuming Signal0 is requested without checking. This results in requests
for Signal1 returning data for Signal0. This patch fixes these
oversights by properly checking for the Signal's id in the respective
callbacks and handling accordingly based on the particular Signal
requested. The trig_inverted member of the mchp_tc_data is removed as
superfluous.

Fixes: 106b104137fd ("counter: Add microchip TCB capture counter")
Cc: stable@vger.kernel.org
Reviewed-by: Kamel Bouhara <kamel.bouhara@bootlin.com>
Link: https://lore.kernel.org/r/20221018121014.7368-1-william.gray@linaro.org/
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>

counter: Move symbols into COUNTER namespace

Counter subsystem symbols are only relevant to counter drivers. A
COUNTER namespace is created to control the availability of these
symbols to modules that import this namespace explicitly.

Cc: Patrick Havelange <patrick.havelange@essensium.com>
Cc: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Cc: Oleksij Rempel <linux@rempel-privat.de>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Kamel Bouhara <kamel.bouhara@bootlin.com>
Cc: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
Acked-by: David Lechner <david@lechnology.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20220815220321.74161-1-william.gray@linaro.org/
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
Link: https://lore.kernel.org/r/8a756df96c24946547a7ece5caa5f654809c5e7f.1664318353.git.william.gray@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

counter: microchip-tcb-capture: Convert to new counter registration

This fixes device lifetime issues where it was possible to free a live
struct device.

Fixes: 106b104137fd ("counter: Add microchip TCB capture counter")
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20211230150300.72196-20-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

counter: microchip-tcb-capture: Convert to counter_priv() wrapper

This is a straight forward conversion to the new counter_priv() wrapper.

Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20211230150300.72196-8-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

counter: microchip-tcb-capture: Drop unused platform_set_drvdata()

The driver doesn't ever use platform_get_drvdata, so drop this unused
call.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20211230150300.72196-4-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

counter: microchip-tcb-capture: Tidy up a false kernel-doc /** marking.

Deals with
W=1 warning This comment starts with '/**', but isn't a kernel-doc comment.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Kamel Bouhara <kamel.bouhara@bootlin.com>
Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Link: https://lore.kernel.org/r/20210930170347.101153-1-jic23@kernel.org

counter: Internalize sysfs interface code

This is a reimplementation of the Generic Counter driver interface.
There are no modifications to the Counter subsystem userspace interface,
so existing userspace applications should continue to run seamlessly.

The purpose of this patch is to internalize the sysfs interface code
among the various counter drivers into a shared module. Counter drivers
pass and take data natively (i.e. u8, u64, etc.) and the shared counter
module handles the translation between the sysfs interface and the
device drivers. This guarantees a standard userspace interface for all
counter drivers, and helps generalize the Generic Counter driver ABI in
order to support the Generic Counter chrdev interface (introduced in a
subsequent patch) without significant changes to the existing counter
drivers.

Note, Counter device registration is the same as before: drivers
populate a struct counter_device with components and callbacks, then
pass the structure to the devm_counter_register function. However,
what's different now is how the Counter subsystem code handles this
registration internally.

Whereas before callbacks would interact directly with sysfs data, this
interaction is now abstracted and instead callbacks interact with native
C data types. The counter_comp structure forms the basis for Counter
extensions.

The counter-sysfs.c file contains the code to parse through the
counter_device structure and register the requested components and
extensions. Attributes are created and populated based on type, with
respective translation functions to handle the mapping between sysfs and
the counter driver callbacks.

The translation performed for each attribute is straightforward: the
attribute type and data is parsed from the counter_attribute structure,
the respective counter driver read/write callback is called, and sysfs
I/O is handled before or after the driver read/write function is called.

Cc: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Cc: Patrick Havelange <patrick.havelange@essensium.com>
Cc: Kamel Bouhara <kamel.bouhara@bootlin.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Syed Nayyar Waris <syednwaris@gmail.com>
Reviewed-by: David Lechner <david@lechnology.com>
Tested-by: David Lechner <david@lechnology.com>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com> # for stm32
Link: https://lore.kernel.org/r/c68b4a1ffb195c1a2f65e8dd5ad7b7c14e79c6ef.1630031207.git.vilhelm.gray@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

counter: Rename counter_count_function to counter_function

The phrase "Counter Count function" is verbose and unintentionally
implies that function is a Count extension. This patch adjusts the
Counter subsystem code to use the more direct "Counter function" phrase
to make the intent of this code clearer.

Cc: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Cc: Patrick Havelange <patrick.havelange@essensium.com>
Cc: Oleksij Rempel <o.rempel@pengutronix.de>
Cc: Kamel Bouhara <kamel.bouhara@bootlin.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: David Lechner <david@lechnology.com>
Acked-by: Syed Nayyar Waris <syednwaris@gmail.com>
Reviewed-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Link: https://lore.kernel.org/r/8268c54d6f42075a19bb08151a37831e22652499.1627990337.git.vilhelm.gray@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

counter: Rename counter_signal_value to counter_signal_level

Signal values will always be levels so let's be explicit it about it to
make the intent of the code clear.

Cc: Oleksij Rempel <o.rempel@pengutronix.de>
Cc: Kamel Bouhara <kamel.bouhara@bootlin.com>
Acked-by: Syed Nayyar Waris <syednwaris@gmail.com>
Reviewed-by: David Lechner <david@lechnology.com>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Link: https://lore.kernel.org/r/3f17010abe2415859cea9a5fddabd3c97f635ff5.1627990337.git.vilhelm.gray@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

counter: Return error code on invalid modes

Only a select set of modes (function, action, etc.) are valid for a
given device configuration. This patch ensures that invalid modes result
in a return -EINVAL. Such a situation should never occur in reality, but
it's good to define a default switch case for the sake of making the
intent of the code clear.

Cc: Kamel Bouhara <kamel.bouhara@bootlin.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Acked-by: David Lechner <david@lechnology.com>
Acked-by: Syed Nayyar Waris <syednwaris@gmail.com>
Reviewed-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Link: https://lore.kernel.org/r/7af82d4e39610da11edce0ee370285fe1cb1eac8.1627990337.git.vilhelm.gray@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

counter: microchip-tcb-capture: Add const qualifier for actions_list array

The struct counter_synapse actions_list member expects a const enum
counter_synapse_action array. This patch adds the const qualifier to the
mchp_tc_synapse_actions to match actions_list.

Cc: Kamel Bouhara <kamel.bouhara@bootlin.com>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Link: https://lore.kernel.org/r/165f9682ce308a60a477aaa56fdae7bc949dc218.1623201081.git.vilhelm.gray@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

counter: microchip-tcb-capture: Add const qualifier for functions_list array

The struct counter_count functions_list member expects a const enum
counter_count_function array. This patch adds the const qualifier to the
mchp_tc_count_functions to match functions_list.

Cc: Kamel Bouhara <kamel.bouhara@bootlin.com>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Link: https://lore.kernel.org/r/74cb91ab7b459563762ec28633cd8808093aa2ad.1623201081.git.vilhelm.gray@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

counter: microchip-tcb-capture: Fix CMR value check

The ATMEL_TC_ETRGEDG_* defines are not masks but rather possible values
for CMR. This patch fixes the action_get() callback to properly check
for these values rather than mask them.

Fixes: 106b104137fd ("counter: Add microchip TCB capture counter")
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Kamel Bouhara <kamel.bouhara@bootlin.com>
Cc: <Stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201114232805.253108-1-vilhelm.gray@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

counter: microchip-tcb-capture: Constify mchp_tc_ops

The only usage of mchp_tc_ops is to assign its address to the ops field
in the counter_device struct which is a const pointer. Make it const to
allow the compiler to put it in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Link: https://lore.kernel.org/r/20200922201941.41328-1-rikard.falkeborn@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

counter: microchip-tcb-capture: check the correct variable

This should be testing "regmap" instead of "priv->regmap". The
"priv->regmap" variable is always zero so it's not an error pointer.

Fixes: 106b104137fd ("counter: Add microchip TCB capture counter")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

counter: Add microchip TCB capture counter

This drivers allows to use the capture mode of the Timer Counter Block
hardware block available in Microchip SoCs through the counter subsystem.

Two functions of the counter are supported for the moment: period
capture and quadrature decoder. The latter is only supported by the
SAMA5 series of SoCs.

For the period capture mode a basic setup has been chosen that will
reset the counter each time the period is actually reached. Of course
the device offers much more possibilities.

For quadrature mode, both channel 0 and 1 must be configured even if we
only capture the position (no revolution/rotation).

Signed-off-by: Kamel Bouhara <kamel.bouhara@bootlin.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>