that they can be used by drivers on non-FDT-configured systems. Only the
functions related to acquiring pins by parsing FDT data remain in
ofw_gpiobus. Also, add two new functions for acquiring gpio pins based on
child device_t and index, or on the bus device_t and pin number. And
finally, defer reserving pins for gpiobus children until they acquire the
pin, rather than reserving them as soon as the child is added (before it's
even known whether the child will attach).
This will allow drivers configured with hints (or any other mechanism) to
use the same code as drivers configured via FDT data. Until now, a hinted
driver and an FDT driver had to be two completely different sets of code,
because hinted drivers could only use gpiobus calls to manipulate pins,
while fdt-configured drivers could not use that API (due to not always being
children of the bus that owns the pins) and had to use the newer
gpio_pin_xxxx() functions. Now drivers can be written in the more
traditional form, where most of the code is shared and only the resource
acquisition code at attachment time changes.
"pin_list" allows to specify child pins as a list of pin numbers.
Existing hint "pins" serves the same purpose but with a 32-bit wide bit
mask. One problem with that is that a controller can have more than 32
pins. One example is amdgpio. Also, a list of numbers is a little bit
more human friendly than a matching bit mask. As a side note, it seems
that in FDT pins are typically specified by their numbers as well.
This commit also adds accessors for instance variables (IVARs) that
define the child pins. My primary goal is to allow a child to be
configured programmatically rather than via hints (assuming that FDT is
not supported on a platform). Also, while a child should not care about
specific pin numbers that are allocated to it, it could be interested in
how many were actually assigned to it.
While there, I removed "flags" instance variable. It was unused.
Reviewed by: mizhka
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D20459
and index. A private function to do exactly that already existed, so this
renames gpio_pin_get_by_ofw_impl() to gpio_pin_get_by_ofw_propidx() and
provides a declaration for it in a public header.
Previously there were functions to get a pin by property name (assuming
there would only be one pin defined for the name), or by index (asuming
the property has the standard name "gpios"). It turns out there are
devicetree bindings that describe properties with names other than "gpios"
which can describe multiple pins. Hence the need to retrieve the Nth item
from a named property.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Trying to build a MIPS platform that uses INTRNG needs this
for this to work right in gpiobusvar.h :
#ifdef INTRNG
struct intr_map_data_gpio {
struct intr_map_data hdr;
...
};
#endif
- Read interrupt properties at bus enumeration time and store
it into global mapping table.
- At bus_activate_resource() time, given mapping entry is resolved and
connected to real interrupt source. A copy of mapping entry is attached
to given resource.
- At bus_setup_intr() time, mapping entry stored in resource is used
for delivery of requested interrupt configuration.
- For MSI/MSIX interrupts, mapping entry is created within
pci_alloc_msi()/pci_alloc_msix() call.
- For legacy PCI interrupts, mapping entry must be created within
pcib_route_interrupt() by pcib driver itself.
Reviewed by: nwhitehorn, andrew
Differential Revision: https://reviews.freebsd.org/D7493
wrap the implementation so that it returns an error if INTRNG support is
not available. It should be possible to write a non-INTRNG implementation
of this function some day. In the meantime, there is code that contains
calls to this function (so the decl is needed), but have runtime checks to
avoid calling it in the non-INTRNG case.
Add gpiobus_release_pin as a counterpart for gpiobus_map_pin. Without it
it's impossible to properly release pin so if kernel module is reloaded
it can't re-use pins again
Current API assumes that "gpios" property belongs to the device's node but for
some binding it's not true: gpiokeys has set of child nodes with this property.
Patch adds new argument instead of replacing device_t because device_t will be
used to track ownership for allocated pins
Reviewed by: mmel
Differential Revision: https://reviews.freebsd.org/D6277
Add new function gpio_alloc_intr_resource(), which allows an allocation
of interrupt resource associated to given gpio pin. It also allows to
specify interrupt configuration.
Note: This functionality is dependent on INTRNG, and must be
implemented in each GPIO controller.
When a gpiobus child is added, use its name to identify the mapped pin
names.
Make the respective changes to libgpio.
Add a new '-n' flag to gpioctl(8) to set the pin name.
Differential Revision: https://reviews.freebsd.org/D2002
Reviewed by: rpaulo
Requested by: many
This new function can be used by other drivers to reserve the use of GPIO
pins.
Anyway, the use of ofw_gpiobus_parse_gpios() is preferred when possible.
Requested by: Michal Meloun
property for devices that doesn't descend directly from gpiobus.
The parser supports multiple pins, different GPIO controllers and can use
arbitrary names for the property (to match the many linux variants:
cd-gpios, power-gpios, wp-gpios, etc.).
Pass the driver name on ofw_gpiobus_add_fdt_child(). Update gpioled to
match.
An usage example of ofw_gpiobus_parse_gpios() will follow soon.
This is the general support to allow the use of GPIO pins as interrupt
sources for direct gpiobus children.
The use of GPIO pins as generic interrupt sources (for an ethernet driver
for example) will only be possible when arm/intrng is complete. Then, most
of this code will need to be rewritten, but it works for now, is better
than what we have and will allow further developments.
Tested on: ar71xx (RSPRO), am335x (BBB), bcm2835 (Raspberry pi)
Differential Revision: https://reviews.freebsd.org/D999
Reviewed by: rpaulo
hold the gpiobus lock between the gpio calls.
gpiobus_acquire_lock() now accepts a third parameter which tells gpiobus
what to do when the bus is already busy.
When GPIOBUS_WAIT wait is used, the calling thread will be put to sleep
until the bus became free.
With GPIOBUS_DONTWAIT the calling thread will receive EWOULDBLOCK right
away and then it can act upon.
This fixes the gpioiic(4) locking issues that arises when doing multiple
concurrent access on the bus.
sys/systm.h must always come after sys/param.h.
Remove sys/types.h which should never be included together with sys/param.h.
Add sys/malloc.h for correctness even if it seems to don't be needed.
Remove more unused headers found by unusedinc (from bde@) and tested with a
universe build.
Reported by: bde
#gpio-cells property.
Add a new ofw_bus method (OFW_BUS_MAP_GPIOS()) that allows the GPIO
controller to implement its own mapping to deal with gpio-specifiers,
allowing the decoding of gpio-specifiers to be controller specific.
The default ofw_bus_map_gpios() decodes the linux standard (#gpio-cells =
<2>) and the FreeBSD standard (#gpio-cells = <3>).
It pass the gpio-specifier flag field to the children as an ivar variable so
they can act upon.
describe GPIO bindings in the system.
Move the GPIOBUS lock macros to gpiobusvar.h as they are now shared between
the OFW and the non OFW versions of GPIO bus.
Export gpiobus_print_pins() so it can also be used on the OFW GPIO bus.
Approved by: adrian (mentor, implicit)
- license clause now contains "AUTHOR AND CONTRIBUTORS"
instead of just "AUTHOR"
- Add license/copyright to gpioc.c
Spotted by: Edward Tomasz Napierala, Andrew Turner
- GPIO bus controller interface
- GPIO bus interface
- Implementation of GPIO led(4) compatible device
- Implementation of iic(4) bus over GPIO (author: Luiz Otavio O Souza)
Tested by: Luiz Otavio O Souza, Alexandr Rybalko