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.
At attach, print the SCL and SDA pin numbers.
Remove a stray blank line.
Remove the GPIOBUS locking from gpioiic_reset(), it is already called with
this lock held. This fixes a crash when you try to scan the iicbus with
i2c(8).
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.
gpioled(4).
Tested on RPi and BBB (using the hardware I2C controller and gpioiic(4) for
the I2C tests). It was also verified for regressions on RSPRO (MIPS/ar71xx)
used as reference for a non OFW-based system.
Update the gpioled(4) and gpioiic(4) man pages with some details and
examples about the FDT/OFW support.
Some compatibility details pointed out by imp@ will follow in subsequent
commits.
Approved by: adrian (mentor, implicit)
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)
it can be overriden by its OFW/FDT version.
Give a chance for GPIO devices that implement the device_identify method to
attach.
Approved by: adrian (mentor)
performance issues.
* Access to the GPIO bus is already locked by requesting
and releasing the bus - thus the lock isn't really needed
for each GPIO pin change.
* Don't lock and unlock the GPIO bus for -each- i2c access -
the i2c bus code is already doing this by calling the upper
layer callback to request/release the bus. This thus locks
the bus for the entirety of the transaction.
TODO:
* Further verify that everything is correctly requesting/
releasing the GPIO bus.
* Look at how to lock the GPIO pin configuration stuff,
potentially by locking/unlocking the bus at the gpiobus
layer.
pins, rather than defaulting to 0 and 1.
This way the pin order can be reversed. It is reversed with the
TP-Link TL-WR1043nd.
Submitted by: Stefan Bethke <stb@lassitu.de>
one. Interestingly, these are actually the default for quite some time
(bus_generic_driver_added(9) since r52045 and bus_generic_print_child(9)
since r52045) but even recently added device drivers do this unnecessarily.
Discussed with: jhb, marcel
- While at it, use DEVMETHOD_END.
Discussed with: jhb
- Also while at it, use __FBSDID.
to kern/subr_bus.c. Simplify this function so that it no longer
depends on malloc() to execute. Identify a few other places where
it makes sense to use device_delete_all_children().
MFC after: 1 week
It seems the D_PSEUDO flag was meant to allow make_dev() to return NULL.
Nowadays we have a different interface for that; make_dev_p(). There's
no need to keep it there.
While there, remove an unneeded D_NEEDMINOR from the gpio driver.
Discussed with: gonzo@ (gpio)
The external gpio pins are connected to a PLD on the i2c bus, unfortunatley
this device does not conform by failing to send an ack after each byte written.
The iicbb driver will abort the transfer when the address is not ack'd and it
would introduce a lot of churn to be able to pass a flag down to
iicbb_start/iicbb_write. Instead we do bad things by grabbing the iicbus but
then doing our own bit banging.
- 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