Currently, reserved register fields must be fully described using dummy
enum IDs (zeroes), one for each possible state (2^bits states).
Add support for describing reserved fields using negative field width
values as shorthands, thus removing the need for dummy values. Apart
from the obvious size reduction due to the removal of the dummy values,
this will also enable merging adjacent reserved fields into a single
field, reducing the number of fields to describe, and thus kernel size.
Update the checker accordingly.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/cad7c92ef039d9a4d039807efc15886a7aa862be.1649865241.git.geert+renesas@glider.be
A kernel hang can be observed when running setserial in a loop on a kernel
with force threaded interrupts. The sequence of events is:
setserial
open("/dev/ttyXXX")
request_irq()
do_stuff()
-> serial interrupt
-> wake(irq_thread)
desc->threads_active++;
close()
free_irq()
kthread_stop(irq_thread)
synchronize_irq() <- hangs because desc->threads_active != 0
The thread is created in request_irq() and woken up, but does not get on a
CPU to reach the actual thread function, which would handle the pending
wake-up. kthread_stop() sets the should stop condition which makes the
thread immediately exit, which in turn leaves the stale threads_active
count around.
This problem was introduced with commit 519cc8652b, which addressed a
interrupt sharing issue in the PCIe code.
Before that commit free_irq() invoked synchronize_irq(), which waits for
the hard interrupt handler and also for associated threads to complete.
To address the PCIe issue synchronize_irq() was replaced with
__synchronize_hardirq(), which only waits for the hard interrupt handler to
complete, but not for threaded handlers.
This was done under the assumption, that the interrupt thread already
reached the thread function and waits for a wake-up, which is guaranteed to
be handled before acting on the stop condition. The problematic case, that
the thread would not reach the thread function, was obviously overlooked.
Make sure that the interrupt thread is really started and reaches
thread_fn() before returning from __setup_irq().
This utilizes the existing wait queue in the interrupt descriptor. The
wait queue is unused for non-shared interrupts. For shared interrupts the
usage might cause a spurious wake-up of a waiter in synchronize_irq() or the
completion of a threaded handler might cause a spurious wake-up of the
waiter for the ready flag. Both are harmless and have no functional impact.
[ tglx: Amended changelog ]
Fixes: 519cc8652b ("genirq: Synchronize only with single thread on free_irq()")
Signed-off-by: Thomas Pfaff <tpfaff@pcs.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/552fe7b4-9224-b183-bb87-a8f36d335690@pcs.com
There are sleep in atomic bug that could cause kernel panic during
firmware download process. The root cause is that nlmsg_new with
GFP_KERNEL parameter is called in fw_dnld_timeout which is a timer
handler. The call trace is shown below:
BUG: sleeping function called from invalid context at include/linux/sched/mm.h:265
Call Trace:
kmem_cache_alloc_node
__alloc_skb
nfc_genl_fw_download_done
call_timer_fn
__run_timers.part.0
run_timer_softirq
__do_softirq
...
The nlmsg_new with GFP_KERNEL parameter may sleep during memory
allocation process, and the timer handler is run as the result of
a "software interrupt" that should not call any other function
that could sleep.
This patch changes allocation mode of netlink message from GFP_KERNEL
to GFP_ATOMIC in order to prevent sleep in atomic bug. The GFP_ATOMIC
flag makes memory allocation operation could be used in atomic context.
Fixes: 9674da8759 ("NFC: Add firmware upload netlink command")
Fixes: 9ea7187c53 ("NFC: netlink: Rename CMD_FW_UPLOAD to CMD_FW_DOWNLOAD")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220504055847.38026-1-duoming@zju.edu.cn
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
By allowing to group multiple monochrome PWM LEDs into multicolor LEDs,
all involved LEDs can be controlled in-sync. This enables using effects
using triggers, etc.
Signed-off-by: Sven Schwermer <sven.schwermer@disruptive-technologies.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
The unit address does not make sense in all cases the multi-led node is
used, e.g. for the upcoming PWM multi-color LED driver.
Signed-off-by: Sven Schwermer <sven.schwermer@disruptive-technologies.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
The regulator LED can easily be adapted to probe from the
device tree.
We switch led_classdev_register() to led_classdev_register_ext()
passing some struct led_init_data init_data that we leave NULL
save the fwnode if platform data isn't present so that it will be
populated from the device tree.
If we have platform data we set up the name from the platform
data but using init_data instead.
Cc: Antonio Ospite <ao2@ao2.it>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Instead of repeating the hard to read &pdev->dev just create a
local struct device *dev in probe().
Cc: Antonio Ospite <ao2@ao2.it>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
The i.MX8M Plus has the same PWM IP as i.MX6 / i.MX7. This IP
and the driver supporting pwm polarity inversion. Switch CPU
device tree fragment to use 3 pwm-cells.
Tested on MBa8MPxL mainboard.
Signed-off-by: Markus Niebel <Markus.Niebel@ew.tq-group.com>
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
The i.MX8M Nano has the same PWM IP as i.MX6 / i.MX7. This IP
and the driver supporting pwm polarity inversion. Switch CPU
device tree fragment to use 3 pwm-cells.
Signed-off-by: Markus Niebel <Markus.Niebel@ew.tq-group.com>
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
The i.MX8M Mini has the same PWM IP as i.MX6 / i.MX7. This IP
and the driver supporting pwm polarity inversion. Switch CPU
device tree fragment to use 3 pwm-cells and correct board
device trees.
Signed-off-by: Markus Niebel <Markus.Niebel@ew.tq-group.com>
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
The i.MX8MQ has the same PWM IP as i.MX6 / i.MX7. This IP and the driver
supporting pwm polarity inversion. Switch CPU device tree fragment to
use 3 pwm-cells and correct board device trees.
Signed-off-by: Markus Niebel <Markus.Niebel@ew.tq-group.com>
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Remove the unnecessary cpu_alert0 and cpu_crit0 TMU node overrides as
these are added dynamically by boot firmware based on CPU temperature
grade.
Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Define the missing clock-names property for the pcie_phy required by
the fsl,imx8-pcie-phy dt bindings.
Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>