This reverts commit aa37baf3d7.
The reverted commit was motivated by a problem observed on stable/12,
but it turns out that a better solution was committed in r348309 but not
MFCed. So, revert this change since it is unnecessary and not really
correct: it assumes that the order in which module metadata records is
defined determines their order in the output linker set. While this
seems to hold in my testing, it is not guaranteed.
Reported by: cem
Discussed with: imp
MFC after: 3 days
PNP info definitions currently have an unfortunate requirement in that
they must follow the associated module definition in the module metadata
linker set. Otherwise devmatch can segfault while processing the linker
hints file since kldxref maintains the order in the linker set.
A number of drivers violate this requirement. In some cases this can
cause devmatch(8) to segfault when processing the linker hints file.
Work around the problem for now simply by adjusting the drivers.
Reviewed by: imp
MFC after: 1 week
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D28260
This is an import of the Google Summer of Code 2018 project completed by
Christian Kramer (and, sadly, ignored by us for two years now). The goals
stated for that project were:
FreeBSD already has support for interrupts implemented in the GPIO
controller drivers of several SoCs, but there are no interfaces to take
advantage of them out of user space yet. The goal of this work is to
implement such an interface by providing descriptors which integrate
with the common I/O system calls and multiplexing mechanisms.
The initial imported code supports the following functionality:
- A kernel driver that provides an interface to the user space; the
existing gpioc(4) driver was enhanced with this functionality.
- Implement support for the most common I/O system calls / multiplexing
mechanisms:
- read() Places the pin number on which the interrupt occurred in the
buffer. Blocking and non-blocking behaviour supported.
- poll()/select()
- kqueue()
- signal driven I/O. Posting SIGIO when the O_ASYNC was set.
- Many-to-many relationship between pins and file descriptors.
- A file descriptor can monitor several GPIO pins.
- A GPIO pin can be monitored by multiple file descriptors.
- Integration with gpioctl and libgpio.
I added some fixes (mostly to locking) and feature enhancements on top of
the original gsoc code. The feature ehancements allow the user to choose
between detailed and summary event reporting. Detailed reporting provides
a record describing each pin change event. Summary reporting provides the
time of the first and last change of each pin, and a count of how many times
it changed state since the last read(2) call. Another enhancement allows
the recording of multiple state change events on multiple pins between each
call to read(2) (the original code would track only a single event at a time).
The phabricator review for these changes timed out without approval, but I
cite it below anyway, because the review contains a series of diffs that
show how I evolved the code from its original state in Christian's github
repo for the gsoc project to what is being commited here. (In effect,
the phab review extends the VC history back to the original code.)
Submitted by: Christian Kramer
Obtained from: https://github.com/ckraemer/freebsd/tree/gsoc2018
Differential Revision: https://reviews.freebsd.org/D27398
Add enough infrastructure for interrupts on children of the pl061 GPIO
controller. As gpiobus already provided these the pl061 driver also needs
to pass requests up the newbus hierarchy.
Currently there are no children that expect to configure interrupts, however
this is expected to change to support the ACPI Event Information interface.
Sponsored by: Innovate UK
As the pl061 driver can be an interrupt controller attach it earlier in the
boot so other drivers can use it.
Use a new GPIO xref to not conflict with the existing root interrupt
controller.
Sponsored by: Innovate UK
On arm64 we may boot via ACPI. In this case we will still try to manage the
gpio providers as if we are using FDT. Fix this by checking if the FDT node
is valid before registering a cross reference.
Sponsored by: Innovate UK
A PL061 is a simple 8 pin GPIO controller. This GPIO device is used to
signal an internal request for shutdown on some virtual machines including
Arm-based Amazon EC2 instances.
Submitted by: Ali Saidi <alisaidi_amazon.com> (previouss version)
Reviewed by: Ali Saidi, manu
Differential Revision: https://reviews.freebsd.org/D24065
Only linux,code is supported as it maps 1:1 to evdev key codes.
No reverse mapping for freebsd,code yet.
Reviewed by: wulf
MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D25940
I2C communication is done by a combination of driving a line low or
letting it float, so that it is either pulled up or driven low by
another party.
r355276 besides the stated goal of the change -- using the new GPIO API
-- also changed the logic, so that active state is signaled by actively
driving a line.
That worked with iicbb prior to r362042, but stopped working after that
commit on at least some hardware. My guess that the breakage was
related to getting an ACK bit. A device expected to be able to drive
SDA actively low, but controller was actively driving it high for some
time.
Anyway, this change seems to fix the problem.
Tested using gpioiic on Orange Pi PC Plus with HTU21 sensor.
Reported by: Nick Kostirya <nikolay.kostirya@i11.co>
Reviewed by: manu
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D25684
It's interesting that similar messages from gpiobus_acquire_pin never
had any prefix while gpiobus_release_pin messages were prefixed with
"gpiobus_acquire_pin".
Anyway, the prefix is not that useful and can be deduced from context.
MFC after: 2 weeks
The attach method uses GPIO_GET_BUS() to get a "newbus" device
that provides a pin. But on hints-based systems a GPIO controller
driver might not be fully initialized yet and it does not know gpiobus
hanging off it. Thus, GPIO_GET_BUS() cannot be called yet.
The reason is that controller drivers typically create a child gpiobus
using gpiobus_attach_bus() and that leads to the following call chain:
gpiobus_attach_bus() -> gpiobus_attach() ->
bus_generic_attach(gpiobus) -> gpioiic_attach().
So, gpioiic_attach() is called before gpiobus_attach_bus() returns.
I observed this bug with nctgpio driver on amd64.
I think that the problem was introduced in r355276.
The fix is to avoid calling GPIO_GET_BUS() from the attach method.
Instead, we know that on hints-based systems only the parent gpiobus can
provide the pins.
Nothing is changed for FDT-based systems.
MFC after: 1 week
r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.
This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.
Mark all obvious cases as MPSAFE. All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT
Approved by: kib (mentor, blanket)
Commented by: kib, gallatin, melifaro
Differential Revision: https://reviews.freebsd.org/D23718
Chase the removal of dev from gpioths_dht_readbytes() in r355540.
Reviewed by: ian
Approved by: will (mentor)
Differential Revision: https://reviews.freebsd.org/D22926
r356087 made it rather innocuous to double-register built-in keyboard
drivers; we now set a flag to indicate that it's been registered and only
act once on a registration anyways. There is no misleading here, as the
follow-up kbd_delete_driver will actually remove the driver as needed now
that the linker set isn't also consulted after kbdinit.
Keyboard drivers are generally registered via linker set. In these cases,
they're also available as kmods which use KPI for registering/unregistering
keyboard drivers outside of the linker set.
For built-in modules, we still fire off MOD_LOAD and maybe even MOD_UNLOAD
if an error occurs, leading to registration via linker set and at MOD_LOAD
time.
This is a minor optimization at best, but it keeps the internal kbd driver
tidy as a future change will merge the linker set driver list into its
internal keyboard_drivers list via SYSINIT and simplify driver lookup by
removing the need to consult the linker set.
Most keyboard drivers are using the genkbd implementations as it is;
formally use them for any that aren't set and make
genkbd_get_fkeystr/genkbd_diag private.
These invocations were directly calling enkbd_diag(), rather than
indirection back through kbdd_diag/kbdsw. While they're functionally
equivent, invoking kbdd_diag where feasible (i.e. not in a diag
implementation) makes it easier to visually identify locking needs in these
other drivers.
of the sensor hardware. Part of the polling process involves signalling
the chip then waiting 20 milliseconds. This was being done with DELAY(),
which is a pretty rude thing to do in a callout. Now a taskqueue_thread
task is scheduled to do the polling, and because sleeping is allowed in
the task context, pause_sbt() replaces DELAY() for the 20ms wait.
changed the sysctl format for the temperature from "I" to "IK", and
correspondingly changed the units from integer degrees C to decikelvin.
For access via sysctl(8) the output will be the same except that now
decimal fractions will be shown when available.
Previously the driver supported the DHT11 sensor. Now it supports
DHT11, DHT12, DHT21, DHT22, AM3201, AM3202.
All these chips are similar, differing primarily in supported temperature
and humidity ranges and accuracy (and, presumably, cost). There are two
basic data formats reported by the various chips, and it is possible to
figure out at runtime which format to use for decoding the data based on
the range of values in a single byte of the humidity measurement. (which
is detailed in a comment block, so I won't recapitulate it here).
functions to handle the sysctls, they all just access simple readonly
integer variables. There's no need to track the oids of the ones we add,
since the teardown is done by newbus code, not the driver itself.
Also remove the DDB code, because it just provides access to the same data
that the sysctls already provide.
At the end of a read cycle, set the gpio pin to INPUT rather than OUTPUT.
The state of the single-wire "bus" when idle should be high; setting the
pin to input allows the external pullup to pull the line high. Setting it
to output (and leaving it driving low) was leading a good read cycle followed
by one that would fail, and it just continued like that forever, effectively
reading the sensor once every 10 seconds instead of 5.
In the attach function, do an initial read from the device before registering
the sysctls for accessing the last-read values, to prevent reading spurious
values for the first 5 seconds after the driver attaches.
Do a callout_drain() in the detach function to prevent crashes after
unloading the module.
of gpio devices by using kenv to add hints for a new device and then do
'devctl rescan gpiobus4' to make the new device(s) attach.
It's not particularly easy to detect whether the 'at' hint has been deleted
for a child device that's currently attached, so this doesn't handle that.
But the user can use devctl commands to manually detach an existing device.
Uses two GPIO pins as MDC (clock) and MDIO (bidirectional I/O), relies
on mii_bitbang.
Tested on SG-3200 where the PHY for one of the ports is wired independently
of the SoC MDIO bus.
Sponsored by: Rubicon Communications, LLC (Netgate)
struct gpio_pin. It turns out these two sets of flags are completely
unrelated to each other.
Also, update the comment for GPIO_ACTIVE_LOW to reflect the fact that it
does get set, somewhat unobviously, by code that parses FDT data. The bits
from the FDT cell containing flags are just copied to gpiobus_pin.flags, so
there's never any obvious reference to the symbol GPIO_ACTIVE_LOW being
stored into the flags field.
FDT bindings document for gpio-i2c devices.
Using the gpio_pin_* functions to acquire/release/manipulate gpio pins
removes the constraint that both gpio pins must belong to the same gpio
controller/bank, and that the gpioiic instance must be a child of gpiobus.
Removing those constraints allows the driver to be fully compatible with
the modern dts bindings for a gpio bitbanged i2c bus.
For hinted attachment, the two gpio pins still must be on the same gpiobus,
and the device instance must be a child of that bus. This preserves
compatibility for existing installations that have use gpioiic(4) with hints.
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.
As part of my journey to make it easy to determine what's relying on tty
bits, remove a couple more. Some of these just outright didn't need it,
while others did rely on <sys/tty.h> pollution for mutex headers.
in ofw_gpiobus_probe() return BUS_PROBE_DEFAULT rather than 0; we are not
the only possible driver to handle this device, we're just slightly better
than the base gpiobus (which probes at BUS_PROBE_GENERIC).
In the time since this code was first written, the gpio controller bindings
aquired the concept of a "hog" node which could be used to preset one or
more gpio pins as input or output at a specified level. This change doesn't
fully implement the hogging concept, it just filters out hog nodes when
instantiating child devices by scanning for child nodes in the fdt data.
The whole concept of having child nodes under the controller node is not
supported by the standard bindings, and appears to be a freebsd extension,
probably left over from the days when we had no support for cross-tree
phandle references in the fdt data.
Some controllers cannot preset future output value while the pin is in
input mode. This adds a fallback for those controllers. The new code
assumes that a controller reports an error in that case.
For example, all hardware supported by nctgpio behaves in that way.
This is a temporary measure. In the future we will use
GPIO_PIN_PRESET_LOW / GPIO_PIN_PRESET_HIGH to preset the output either
in hardware, if supported, or in software (e.g., in
gpiobus_pin_setflags).
While here, I extracted common functionality of gpioiic_set{sda,scl} and
gpioiic_get{sda,scl} to gpioiic_setpin and gpioiic_getpin respectively.
MFC after: 2 weeks
"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
This fixes a panic in Espressobin when gpioregulator fails to allocate the
GPIO pin (the GPIO controller is not there).
Sponsored by: Rubicon Communications, LLC (Netgate)
hint.gpioled.%d.state determines the initial state of the LED when the
driver takes control over it:
0 - the LED is off
1 - the LED is on
-1 - the LED is kept as it was
While here, add a module version declaration.
MFC after: 2 weks
