The Timer Counter Block (TCB) exposes several kinds of events to the
Counter framework, but not every event is meaningful on every hardware
channel. Add a `watch_validate()` callback so userspace may register only
the combinations actually supported:
* Channel 0 (COUNTER_MCHP_EVCHN_CV, COUNTER_MCHP_EVCHN_RA)
- COUNTER_EVENT_CAPTURE
- COUNTER_EVENT_CHANGE_OF_STATE
- COUNTER_EVENT_OVERFLOW
* Channel 1 (COUNTER_MCHP_EVCHN_RB)
- COUNTER_EVENT_CAPTURE
* Channel 2 (COUNTER_MCHP_EVCHN_RC)
- COUNTER_EVENT_THRESHOLD
Any other request is rejected with `-EINVAL`.
Signed-off-by: Dharma Balasubiramani <dharma.b@microchip.com>
Link: https://lore.kernel.org/r/20250520-counter-tcb-v3-1-4631e2aff7ed@microchip.com
Signed-off-by: William Breathitt Gray <wbg@kernel.org>
Pull char/misc fixes from Greg KH:
"Here are two counter driver fixes that I realized I never sent to you
for 6.14-final.
They have been in my for weeks, as well as linux-next, my fault for
not sending them earlier. They are:
- bugfix for stm32-lptimer-cnt counter driver
- bugfix for microchip-tcb-capture counter driver
Again, these have been in linux-next for weeks with no reported
issues"
* tag 'char-misc-6.15-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
counter: microchip-tcb-capture: Fix undefined counter channel state on probe
counter: stm32-lptimer-cnt: fix error handling when enabling
In Capture mode, the RC register serves as a compare register for the
Timer Counter Channel. When a the Counter Value reaches the RC value, a
RC Compare event occurs (COUNTER_EVENT_THRESHOLD). This patch exposes
the RC register to userspace as the 'compare' Count extension, thus
allowing users to configure the threshold condition for these events.
Acked-by: Bence Csókás <csokas.bence@prolan.hu>
Link: https://lore.kernel.org/r/20250306-introduce-compare-component-v1-2-93993b3dca9c@kernel.org
Signed-off-by: William Breathitt Gray <wbg@kernel.org>
William writes:
First set of Counter fixes for 6.6
The counter_get_ext() function would incorrectly refer to the first
element of the extensions array to handle component array extensions
when they are located at a different index; a fix is provided to index
to the correct element in the array for this case. A fix for the
microchip-tcb-capture is provided as well to correct an inverted
internal GCLK logic for clock selection.
* tag 'counter-fixes-for-6.6a' of git://git.kernel.org/pub/scm/linux/kernel/git/wbg/counter:
counter: microchip-tcb-capture: Fix the use of internal GCLK logic
counter: chrdev: fix getting array extensions
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>
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: 106b104137 ("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>
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>
This should be testing "regmap" instead of "priv->regmap". The
"priv->regmap" variable is always zero so it's not an error pointer.
Fixes: 106b104137 ("counter: Add microchip TCB capture counter")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
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>
