Pull pwm fixes from Uwe Kleine-König:
"Two driver fixes
After having added some more code to libpwm checking the pwm rounding
rules for the userspace interface I spotted an issue in the pwm-stm32
driver where in some cases involving inverted polarity the wrong
hardware settings for the duty offset are chosen. I think it has
little practical effect because the duty offset is in most cases an
artificial property of the output waveform. Still it's relevant to get
this fixed because this driver serves as a reference implementation
for the still young waveform API.
The second fix addresses a sleep-in-atomic issue in the pwm-atmel-tcb
driver"
* tag 'pwm/fixes-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux:
pwm: atmel-tcb: Cache clock rates and mark chip as atomic
pwm: stm32: Fix rounding issue for requests with inverted polarity
atmel_tcb_pwm_apply() holds tcbpwmc->lock as a spinlock via
guard(spinlock)() and then calls atmel_tcb_pwm_config(), which calls
clk_get_rate() twice. clk_get_rate() acquires clk_prepare_lock (a
mutex), so this is a sleep-in-atomic-context violation.
On CONFIG_DEBUG_ATOMIC_SLEEP kernels every pwm_apply_state() that
enables or reconfigures the PWM triggers a "BUG: sleeping function
called from invalid context" warning.
Acquire exclusive control over the clock rates with
clk_rate_exclusive_get() at probe time and cache the rates in struct
atmel_tcb_pwm_chip, then read the cached rates from
atmel_tcb_pwm_config(). This keeps the spinlock-based mutual exclusion
introduced in commit 37f7707077 ("pwm: atmel-tcb: Fix race condition
and convert to guards") and removes the sleeping calls from the atomic
section.
With no sleeping calls left in .apply() and the regmap-mmio bus already
running with fast_io=true, also mark the chip as atomic so consumers
can use pwm_apply_atomic() from atomic context.
Fixes: 37f7707077 ("pwm: atmel-tcb: Fix race condition and convert to guards")
Signed-off-by: Sangyun Kim <sangyun.kim@snu.ac.kr>
Link: https://patch.msgid.link/20260419080838.3192357-1-sangyun.kim@snu.ac.kr
[ukleinek: Ensure .clk is enabled before calling clk_get_rate on it.]
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
The calculation of the number of pwm clk ticks from a time length in
nanoseconds involves a division and thus some rounding. That might
result in
duty_ticks + offset_ticks < period_ticks
despite
duty_length_ns + duty_offset_ns >= period_length_ns
. The stm32 PWM cannot configure offset_ticks freely, it can only select
0 or period_length_ns - duty_length_ns---that is the classic normal and
inverted polarity. The decision to select the hardware polarity must be
done using the ticks values and not the nanoseconds times to adhere to
the rounding rules by the pwm core.
With the pwm clk running at 208900 kHz on my test machine
(stm32mp135f-dk), a test case that was handled wrong is:
# pwmround -P 9999962 -O 24970 -D 9974992
period_length = 9999962
duty_length = 9974840
duty_offset = 25123
With this change applied the rounding is done correctly:
# pwmround -P 9999962 -O 24970 -D 9974992
period_length = 9999962
duty_length = 9974840
duty_offset = 0
Fixes: deaba9cff8 ("pwm: stm32: Implementation of the waveform callbacks")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://patch.msgid.link/c5e7767cee821b5f6e00f95bd14a5e13015646fb.1776264104.git.u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Pull pwm updates from Uwe Kleine-König:
"Just two minor fixes, a device tree binding addition to support a few
more SoCs (without the need for driver adaptions), a driver include
cleanup and the addition of the #linux-pwm irc channel to MAINTAINERS"
* tag 'pwm/for-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux:
pwm: th1520: fix `CLIPPY=1` warning
pwm: jz4740: Drop unused include
MAINTAINERS: Add #linux-pwm irc channel to pwm entry
dt-bindings: pwm: amlogic: Document A4 A5 and T7 PWM
pwm: imx-tpm: Count the number of enabled channels in probe
On a soft reset TPM PWM IP may preserve its internal state from previous
runtime, therefore on a subsequent OS boot and driver probe
"enable_count" value and TPM PWM IP internal channels "enabled" states
may get unaligned. In consequence on a suspend/resume cycle the call "if
(--tpm->enable_count == 0)" may lead to "enable_count" overflow the
system being blocked from entering suspend due to:
if (tpm->enable_count > 0)
return -EBUSY;
Fix the problem by counting the enabled channels in probe function.
Signed-off-by: Viorel Suman (OSS) <viorel.suman@oss.nxp.com>
Fixes: 738a1cfec2 ("pwm: Add i.MX TPM PWM driver support")
Link: https://patch.msgid.link/20260311123309.348904-1-viorel.suman@oss.nxp.com
Cc: stable@vger.kernel.org
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
This is the exact same thing as the 'alloc_obj()' version, only much
smaller because there are a lot fewer users of the *alloc_flex()
interface.
As with alloc_obj() version, this was done entirely with mindless brute
force, using the same script, except using 'flex' in the pattern rather
than 'objs*'.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
Pull driver core updates from Danilo Krummrich:
"Bus:
- Ensure bus->match() is consistently called with the device lock
held
- Improve type safety of bus_find_device_by_acpi_dev()
Devtmpfs:
- Parse 'devtmpfs.mount=' boot parameter with kstrtoint() instead of
simple_strtoul()
- Avoid sparse warning by making devtmpfs_context_ops static
IOMMU:
- Do not register the qcom_smmu_tbu_driver in arm_smmu_device_probe()
MAINTAINERS:
- Add the new driver-core mailing list (driver-core@lists.linux.dev)
to all relevant entries
- Add missing tree location for "FIRMWARE LOADER (request_firmware)"
- Add driver-model documentation to the "DRIVER CORE" entry
- Add missing driver-core maintainers to the "AUXILIARY BUS" entry
Misc:
- Change return type of attribute_container_register() to void; it
has always been infallible
- Do not export sysfs_change_owner(), sysfs_file_change_owner() and
device_change_owner()
- Move devres_for_each_res() from the public devres header to
drivers/base/base.h
- Do not use a static struct device for the faux bus; allocate it
dynamically
Revocable:
- Patches for the revocable synchronization primitive have been
scheduled for v7.0-rc1, but have been reverted as they need some
more refinement
Rust:
- Device:
- Support dev_printk on all device types, not just the core Device
struct; remove now-redundant .as_ref() calls in dev_* print
calls
- Devres:
- Introduce an internal reference count in Devres<T> to avoid a
deadlock condition in case of (indirect) nesting
- DMA:
- Allow drivers to tune the maximum DMA segment size via
dma_set_max_seg_size()
- I/O:
- Introduce the concept of generic I/O backends to handle
different kinds of device shared memory through a common
interface.
This enables higher-level concepts such as register
abstractions, I/O slices, and field projections to be built
generically on top.
In a first step, introduce the Io, IoCapable<T>, and IoKnownSize
trait hierarchy for sharing a common interface supporting offset
validation and bound-checking logic between I/O backends.
- Refactor MMIO to use the common I/O backend infrastructure
- Misc:
- Add __rust_helper annotations to C helpers for inlining into
Rust code
- Use "kernel vertical" style for imports
- Replace kernel::c_str! with C string literals
- Update ARef imports to use sync::aref
- Use pin_init::zeroed() for struct auxiliary_device_id and
debugfs file_operations initialization
- Use LKMM atomic types in debugfs doc-tests
- Various minor comment and documentation fixes
- PCI:
- Implement PCI configuration space accessors using the common I/O
backend infrastructure
- Document pci::Bar device endianness assumptions
- SoC:
- Abstractions for struct soc_device and struct soc_device_attribute
- Sample driver for soc::Device"
* tag 'driver-core-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (79 commits)
rust: devres: fix race condition due to nesting
rust: dma: add missing __rust_helper annotations
samples: rust: pci: Remove some additional `.as_ref()` for `dev_*` print
Revert "revocable: Revocable resource management"
Revert "revocable: Add Kunit test cases"
Revert "selftests: revocable: Add kselftest cases"
driver core: remove device_change_owner() export
sysfs: remove exports of sysfs_*change_owner()
driver core: disable revocable code from build
revocable: Add KUnit test for concurrent access
revocable: fix SRCU index corruption by requiring caller-provided storage
revocable: Add KUnit test for provider lifetime races
revocable: Fix races in revocable_alloc() using RCU
driver core: fix inverted "locked" suffix of driver_match_device()
rust: io: move MIN_SIZE and io_addr_assert to IoKnownSize
rust: pci: re-export ConfigSpace
rust: dma: allow drivers to tune max segment size
gpu: tyr: remove redundant `.as_ref()` for `dev_*` print
rust: auxiliary: use `pin_init::zeroed()` for device ID
rust: debugfs: use pin_init::zeroed() for file_operations
...
The previous Io<SIZE> type combined both the generic I/O access helpers
and MMIO implementation details in a single struct. This coupling prevented
reusing the I/O helpers for other backends, such as PCI configuration
space.
Establish a clean separation between the I/O interface and concrete
backends by separating generic I/O helpers from MMIO implementation.
Introduce a new trait hierarchy to handle different access capabilities:
- IoCapable<T>: A marker trait indicating that a backend supports I/O
operations of a certain type (u8, u16, u32, or u64).
- Io trait: Defines fallible (try_read8, try_write8, etc.) and infallibile
(read8, write8, etc.) I/O methods with runtime bounds checking and
compile-time bounds checking.
- IoKnownSize trait: The marker trait for types support infallible I/O
methods.
Move the MMIO-specific logic into a dedicated Mmio<SIZE> type that
implements the Io traits. Rename IoRaw to MmioRaw and update consumers to
use the new types.
Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Bjorn Helgaas <helgaas@kernel.org>
Cc: Gary Guo <gary@garyguo.net>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Zhi Wang <zhiw@nvidia.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260121202212.4438-3-zhiw@nvidia.com
[ Add #[expect(unused)] to define_{read,write}!(). - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
The period and duty cycle configurations on J7200 and J784S4 SoCs
does not get reflected after setting them using sysfs nodes.
This is because at the end of ehrpwm_pwm_config function,
the put_sync function is called which resets the hardware.
Hold the PWM controller out of low-power mode during .apply() to
make sure it accepts the writes to its registers.
This renders the calls to pm_runtime_get_sync() and
pm_runtime_put_sync() in ehrpwm_pwm_config() into no-ops, so
these can be dropped.
Fixes: 5f027d9b83 ("pwm: tiehrpwm: Implement .apply() callback")
Signed-off-by: Gokul Praveen <g-praveen@ti.com>
Suggested-by: Uwe Kleine-König <ukleinek@kernel.org>
Link: https://patch.msgid.link/20260121061134.15466-1-g-praveen@ti.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
The `pwm::Registration::register` function provides no guarantee that the
function isn't called twice with the same pwm chip, which is considered
unsafe.
Add `pwm::UnregisteredChip` as wrapper around `pwm::Chip`.
Implement `pwm::UnregisteredChip::register` for the registration. This
function takes ownership of `pwm::UnregisteredChip` and therefore
guarantees that the registration can't be called twice on the same pwm
chip.
Signed-off-by: Markus Probst <markus.probst@posteo.de>
Tested-by: Michal Wilczynski <m.wilczynski@samsung.com>
Acked-by: Michal Wilczynski <m.wilczynski@samsung.com>
Link: https://patch.msgid.link/20251202-pwm_safe_register-v2-1-7a2e0d1e287f@posteo.de
[ukleinek: fixes a typo that Michal pointed out during review]
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
copy_to_user() returns the number of bytes not copied, thus if there is
a problem a positive number. However the ioctl callback is supposed to
return a negative error code on error.
This error is a unfortunate as strictly speaking it became ABI with the
introduction of pwm character devices. However I never saw the issue in
real life -- I found this by code inspection -- and it only affects an
error case where readonly memory is passed to the ioctls or the address
mapping changes while the ioctl is active. Also there are already error
cases returning negative values, so the calling code must be prepared to
see such values already.
Fixes: 9c06f26ba5 ("pwm: Add support for pwmchip devices for faster and easier userspace access")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://patch.msgid.link/20260119151325.571857-2-u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Pull pwm fix from Uwe Kleine-König:
"Fix missing th1520 Kconfig dependencies
This tightens the dependency for the new pwm driver written in Rust to
make build bots and obviously also users happy"
* tag 'pwm/for-6.19-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux:
pwm: th1520: Fix missing Kconfig dependencies
Pull driver core updates from Danilo Krummrich:
"Arch Topology:
- Move parse_acpi_topology() from arm64 to common code for reuse in
RISC-V
CPU:
- Expose housekeeping CPUs through /sys/devices/system/cpu/housekeeping
- Print a newline (or 0x0A) instead of '(null)' reading
/sys/devices/system/cpu/nohz_full when nohz_full= is not set
debugfs
- Remove (broken) 'no-mount' mode
- Remove redundant access mode checks in debugfs_get_tree() and
debugfs_create_*() functions
Devres:
- Remove unused devm_free_percpu() helper
- Move devm_alloc_percpu() from device.h to devres.h
Firmware Loader:
- Replace simple_strtol() with kstrtoint()
- Do not call cancel_store() when no upload is in progress
kernfs:
- Increase struct super_block::maxbytes to MAX_LFS_FILESIZE
- Fix a missing unwind path in __kernfs_new_node()
Misc:
- Increase the name size in struct auxiliary_device_id to 40
characters
- Replace system_unbound_wq with system_dfl_wq and add WQ_PERCPU to
alloc_workqueue()
Platform:
- Replace ERR_PTR() with IOMEM_ERR_PTR() in platform ioremap
functions
Rust:
- Auxiliary:
- Unregister auxiliary device on parent device unbind
- Move parent() to impl Device; implement device context aware
parent() for Device<Bound>
- Illustrate how to safely obtain a driver's device private data
when calling from an auxiliary driver into the parant device
driver
- DebugFs:
- Implement support for binary large objects
- Device:
- Let probe() return the driver's device private data as pinned
initializer, i.e. impl PinInit<Self, Error>
- Implement safe accessor for a driver's device private data for
Device<Bound> (returned reference can't out-live driver binding
and guarantees the correct private data type)
- Implement AsBusDevice trait, to be used by class device
abstractions to derive the bus device type of the parent device
- DMA:
- Store raw pointer of allocation as NonNull
- Use start_ptr() and start_ptr_mut() to inherit correct
mutability of self
- FS:
- Add file::Offset type alias
- I2C:
- Add abstractions for I2C device / driver infrastructure
- Implement abstractions for manual I2C device registrations
- I/O:
- Use "kernel vertical" style for imports
- Define ResourceSize as resource_size_t
- Move ResourceSize to top-level I/O module
- Add type alias for phys_addr_t
- Implement Rust version of read_poll_timeout_atomic()
- PCI:
- Use "kernel vertical" style for imports
- Move I/O and IRQ infrastructure to separate files
- Add support for PCI interrupt vectors
- Implement TryInto<IrqRequest<'a>> for IrqVector<'a> to convert
an IrqVector bound to specific pci::Device into an IrqRequest
bound to the same pci::Device's parent Device
- Leverage pin_init_scope() to get rid of redundant Result in IRQ
methods
- PinInit:
- Add {pin_}init_scope() to execute code before creating an
initializer
- Platform:
- Leverage pin_init_scope() to get rid of redundant Result in IRQ
methods
- Timekeeping:
- Implement abstraction of udelay()
- Uaccess:
- Implement read_slice_partial() and read_slice_file() for
UserSliceReader
- Implement write_slice_partial() and write_slice_file() for
UserSliceWriter
sysfs:
- Prepare the constification of struct attribute"
* tag 'driver-core-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (75 commits)
rust: pci: fix build failure when CONFIG_PCI_MSI is disabled
debugfs: Fix default access mode config check
debugfs: Remove broken no-mount mode
debugfs: Remove redundant access mode checks
driver core: Check drivers_autoprobe for all added devices
driver core: WQ_PERCPU added to alloc_workqueue users
driver core: replace use of system_unbound_wq with system_dfl_wq
tick/nohz: Expose housekeeping CPUs in sysfs
tick/nohz: avoid showing '(null)' if nohz_full= not set
sysfs/cpu: Use DEVICE_ATTR_RO for nohz_full attribute
kernfs: fix memory leak of kernfs_iattrs in __kernfs_new_node
fs/kernfs: raise sb->maxbytes to MAX_LFS_FILESIZE
mod_devicetable: Bump auxiliary_device_id name size
sysfs: simplify attribute definition macros
samples/kobject: constify 'struct foo_attribute'
samples/kobject: add is_visible() callback to attribute group
sysfs: attribute_group: enable const variants of is_visible()
sysfs: introduce __SYSFS_FUNCTION_ALTERNATIVE()
sysfs: transparently handle const pointers in ATTRIBUTE_GROUPS()
sysfs: attribute_group: allow registration of const attribute
...
