During my experiments to make dlm robust against tcpkill application I
was able to run sometimes in a circular lock dependency warning between
clusters_root.subsys.su_mutex and con->sock_mutex. We don't need to
held the sock_mutex when getting the mark value which held the
clusters_root.subsys.su_mutex. This patch moves the specific handling
just before the sock_mutex will be held.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
If programs in prog_tests using skeletons declare the 'skel' variable as
global but not static, that will lead to linker errors on the final link of
the prog_tests binary due to duplicate symbols. Fix a few instances of this.
Fixes: b18c1f0aa4 ("bpf: selftest: Adapt sock_fields test to use skel and global variables")
Fixes: 9a856cae22 ("bpf: selftest: Add test_btf_skc_cls_ingress")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200929123026.46751-1-toke@redhat.com
After 'peeking' the ring, the consumer, not the producer, reads the data.
Fix this mistake in the comments.
Fixes: 15d8c9162c ("xsk: Add function naming comments and reorder functions")
Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20200928082344.17110-1-ciara.loftus@intel.com
The new test for task iteration in bpf_iter checks (in do_btf_read()) if it
should be skipped due to missing __builtin_btf_type_id. However, this
'skip' verdict is not propagated to the caller, so the parent test will
still fail. Fix this by also skipping the rest of the parent test if the
skip condition was reached.
Fixes: b72091bd4e ("selftests/bpf: Add test for bpf_seq_printf_btf helper")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20200929123004.46694-1-toke@redhat.com
The Makefile in bpf/preload builds a local copy of libbpf, but does not
properly clean up after itself. This can lead to subsequent compilation
failures, since the feature detection cache is kept around which can lead
subsequent detection to fail.
Fix this by properly setting clean-files, and while we're at it, also add a
.gitignore for the directory to ignore the build artifacts.
Fixes: d71fa5c976 ("bpf: Add kernel module with user mode driver that populates bpffs.")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200927193005.8459-1-toke@redhat.com
Alan Maguire says:
====================
Resolve issues in bpf selftests introduced with BTF-based kernel data
display selftests; these are
- a warning introduced in snprintf_btf.c; and
- compilation failures with old kernels vmlinux.h
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Andrii reports that bpf selftests relying on "struct btf_ptr" and BTF_F_*
values will not build as vmlinux.h for older kernels will not include
"struct btf_ptr" or the BTF_F_* enum values. Undefine and redefine
them to work around this.
Fixes: b72091bd4e ("selftests/bpf: Add test for bpf_seq_printf_btf helper")
Fixes: 076a95f5af ("selftests/bpf: Add bpf_snprintf_btf helper tests")
Reported-by: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/1601379151-21449-3-git-send-email-alan.maguire@oracle.com
CONFIG_EFI_VARS controls the code that exposes EFI variables via
sysfs entries, which was deprecated before support for non-Intel
architectures was added to EFI. So let's limit its availability
to Intel architectures for the time being, and hopefully remove
it entirely in the not too distant future.
While at it, let's remove the module alias so that the module is
no longer loaded automatically.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Remove some false dependencies on CONFIG_EFI_VARS, which only controls
the creation of the sysfs entries, whereas the underlying functionality
that these modules rely on is enabled unconditionally when CONFIG_EFI
is set.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
The gsmi code does not actually rely on CONFIG_EFI_VARS, since it only
uses the efivars abstraction that is included unconditionally when
CONFIG_EFI is defined. CONFIG_EFI_VARS controls the inclusion of the
code that exposes the sysfs entries, and which has been deprecated for
some time.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
efivars_sysfs_init() is only used locally in the source file that
defines it, so make it static and unexport it.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
The worker thread that gets kicked off to sync the state of the
EFI variable list is only used by the EFI pstore implementation,
and is defined in its source file. So let's move its scheduling
there as well. Since our efivar_init() scan will bail on duplicate
entries, there is no need to disable the workqueue like we did
before, so we can run it unconditionally.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
The EFI pstore implementation relies on the 'efivars' abstraction,
which encapsulates the EFI variable store in a way that can be
overridden by other backing stores, like the Google SMI one.
On top of that, the EFI pstore implementation also relies on the
efivars.ko module, which is a separate layer built on top of the
'efivars' abstraction that exposes the [deprecated] sysfs entries
for each variable that exists in the backing store.
Since the efivars.ko module is deprecated, and all users appear to
have moved to the efivarfs file system instead, let's prepare for
its removal, by removing EFI pstore's dependency on it.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Fix a couple of issues in the new mokvar-table handling code, as
pointed out by Arvind and Boris:
- don't bother checking the end of the physical region against the start
address of the mokvar table,
- ensure that we enter the loop with err = -EINVAL,
- replace size_t with unsigned long to appease pedantic type equality
checks.
Reviewed-by: Arvind Sankar <nivedita@alum.mit.edu>
Reviewed-by: Lenny Szubowicz <lszubowi@redhat.com>
Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
A couple of last minute fixes
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio fixes from Michael Tsirkin:
"A couple of last minute fixes"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
vhost-vdpa: fix backend feature ioctls
vhost: Fix documentation
A late set given it seems the 5.10 cycle is going to start a bit later
than expected and quite a bit came in. Includes some late breaking
fixes that can wait for the merge window.
New device support
* ad9467
- ad9434 support including dt bindings update
- ad9265 support including dt bindings update
Yaml conversion
* amlogic,meson-saradc
Core rework (heading towards multiple buffer support)
* refactor iio_device_register_eventset
* Null-ify IIO device's event_interface during unregister.
Features
* ad7291
- convert from platform_data to devicetree including bindings doc.
* core
- Add titles to a few IIO config symbols to allow simpler out of tree
building. It does little harm so why not enable it.
Fixes
* ad7292
- Fix missing of_node_put()
* at91-sama5d2
- Fix a crash due to missordering of dma enabling as a result of recent
IIO wide rework.
* gyro-adc
- Fix missing of_node_put()
* ltc2983
- Fix missing of_node_put()
* stm32-adc
- Fix an issue with runtime autosuspend related to parent autosuspending.
Cleanups
* counter/ti-eqep
- Tidy up a , instead of ;
* buffer-dmaengine
- Drop the unmanaged allocator functions as no one is using them.
* at91-sama5d2
- devm_platform_get_and_ioremap_resouce() replacing boilerplate.
* cros_ec
- move the hw fifo attributes setup into the cros_ec core.
* gp2ap002
- comment typo
* microchip-tcb-capture:
- consitifcation
* ssp
- Use PLATFORM_DEVID_NONE instead of -1 to convey true meaning.
* stm32-dfsdm
- devm_platform_get_and_ioremap_resouce() replacing boilerplate.
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Merge tag 'iio-for-5.10c' of https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next
Jonathan writes:
3rd set of new device support features and cleanup for IIO in the 5.10 cycle.
A late set given it seems the 5.10 cycle is going to start a bit later
than expected and quite a bit came in. Includes some late breaking
fixes that can wait for the merge window.
New device support
* ad9467
- ad9434 support including dt bindings update
- ad9265 support including dt bindings update
Yaml conversion
* amlogic,meson-saradc
Core rework (heading towards multiple buffer support)
* refactor iio_device_register_eventset
* Null-ify IIO device's event_interface during unregister.
Features
* ad7291
- convert from platform_data to devicetree including bindings doc.
* core
- Add titles to a few IIO config symbols to allow simpler out of tree
building. It does little harm so why not enable it.
Fixes
* ad7292
- Fix missing of_node_put()
* at91-sama5d2
- Fix a crash due to missordering of dma enabling as a result of recent
IIO wide rework.
* gyro-adc
- Fix missing of_node_put()
* ltc2983
- Fix missing of_node_put()
* stm32-adc
- Fix an issue with runtime autosuspend related to parent autosuspending.
Cleanups
* counter/ti-eqep
- Tidy up a , instead of ;
* buffer-dmaengine
- Drop the unmanaged allocator functions as no one is using them.
* at91-sama5d2
- devm_platform_get_and_ioremap_resouce() replacing boilerplate.
* cros_ec
- move the hw fifo attributes setup into the cros_ec core.
* gp2ap002
- comment typo
* microchip-tcb-capture:
- consitifcation
* ssp
- Use PLATFORM_DEVID_NONE instead of -1 to convey true meaning.
* stm32-dfsdm
- devm_platform_get_and_ioremap_resouce() replacing boilerplate.
* tag 'iio-for-5.10c' of https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio: (25 commits)
iio: adc: gyroadc: fix leak of device node iterator
iio: adc: stm32-adc: fix runtime autosuspend delay when slow polling
iio: adc: at91-sama5d2_adc: fix DMA conversion crash
iio: ad7292: Fix of_node refcounting
iio: ltc2983: Fix of_node refcounting
counter: use semicolons rather than commas to separate statements
iio: buffer: Kconfig: add title for IIO_TRIGGERED_BUFFER symbol
iio: Kconfig: Provide title for IIO_TRIGGERED_EVENT symbol
iio: dma-buffer: Kconfig: Provide titles for IIO DMA Kconfig symbols
iio: cros_ec: unify hw fifo attributes into the core file
dt-bindings: iio: ad9467: add entries for for AD9434 & AD9265 ADCs
iio: adc: ad9467: add support for AD9265 high-speed ADC
iio: adc: ad9467: add support for AD9434 high-speed ADC
iio: adc: ad9467: wrap a axi-adc chip-info into a ad9467_chip_info type
iio: buffer-dmaengine: remove non managed alloc/free
iio: adc: stm32-dfsdm: Use devm_platform_get_and_ioremap_resource()
iio: adc: at91-sama5d2_adc: Use devm_platform_get_and_ioremap_resource()
iio: ssp: use PLATFORM_DEVID_NONE
dt-bindings: iio: adc: ad7291: add binding
iio: adc: ad7291: convert to device tree
...
The first thing that the ftrace function callback helper functions should do
is to check for recursion. Peter Zijlstra found that when
"rcu_is_watching()" had its notrace removed, it caused perf function tracing
to crash. This is because the call of rcu_is_watching() is tested before
function recursion is checked and and if it is traced, it will cause an
infinite recursion loop.
rcu_is_watching() should still stay notrace, but to prevent this should
never had crashed in the first place. The recursion prevention must be the
first thing done in callback functions.
Link: https://lore.kernel.org/r/20200929112541.GM2628@hirez.programming.kicks-ass.net
Cc: stable@vger.kernel.org
Cc: Paul McKenney <paulmck@kernel.org>
Fixes: c68c0fa293 ("ftrace: Have ftrace_ops_get_func() handle RCU and PER_CPU flags too")
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reported-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Some code was removed but the variables were still there, and some
parameters have been changed to be queried from firmware. So the
definitions of them are no longer needed.
Fixes: 2a3d923f87 ("RDMA/hns: Replace magic numbers with #defines")
Fixes: 82e620d9c3 ("RDMA/hns: Modify the data structure of hns_roce_av")
Fixes: 8254746978 ("IB/hns: Implement the add_gid/del_gid and optimize the GIDs management")
Fixes: 21b97f5387 ("RDMA/hns: Fixup qp release bug")
Link: https://lore.kernel.org/r/1601371934-40003-1-git-send-email-liweihang@huawei.com
Signed-off-by: Lang Cheng <chenglang@huawei.com>
Signed-off-by: Weihang Li <liweihang@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Add missing of_node_put calls when exiting the for_each_child_of_node
loop in rcar_gyroadc_parse_subdevs early.
Also add goto-exception handling for the error paths in that loop.
Fixes: 059c53b323 ("iio: adc: Add Renesas GyroADC driver")
Signed-off-by: Tobias Jordan <kernel@cdqe.de>
Link: https://lore.kernel.org/r/20200926161946.GA10240@agrajag.zerfleddert.de
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
When the ADC is runtime suspended and starting a conversion, the stm32-adc
driver calls pm_runtime_get_sync() that gets cascaded to the parent
(e.g. runtime resume of stm32-adc-core driver). This also kicks the
autosuspend delay (e.g. 2s) of the parent.
Once the ADC is active, calling pm_runtime_get_sync() again (upon a new
capture) won't kick the autosuspend delay for the parent (stm32-adc-core
driver) as already active.
Currently, this makes the stm32-adc-core driver go in suspend state
every 2s when doing slow polling. As an example, doing a capture, e.g.
cat in_voltageY_raw at a 0.2s rate, the auto suspend delay for the parent
isn't refreshed. Once it expires, the parent immediately falls into
runtime suspended state, in between two captures, as soon as the child
driver falls into runtime suspend state:
- e.g. after 2s, + child calls pm_runtime_put_autosuspend() + 100ms
autosuspend delay of the child.
- stm32-adc-core switches off regulators, clocks and so on.
- They get switched on back again 100ms later in this example (at 2.2s).
So, use runtime_idle() callback in stm32-adc-core driver to call
pm_runtime_mark_last_busy() for the parent driver (stm32-adc-core),
to avoid this.
Fixes: 9bdbb1139c ("iio: adc: stm32-adc: add power management support")
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/1593615328-5180-1-git-send-email-fabrice.gasnier@st.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
After the move of the postenable code to preenable, the DMA start was
done before the DMA init, which is not correct.
The DMA is initialized in set_watermark. Because of this, we need to call
the DMA start functions in set_watermark, after the DMA init, instead of
preenable hook, when the DMA is not properly setup yet.
Fixes: f3c034f617 ("iio: at91-sama5d2_adc: adjust iio_triggered_buffer_{predisable,postenable} positions")
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Link: https://lore.kernel.org/r/20200923121748.49384-1-eugen.hristev@microchip.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The temp buffer size variable for trace_find_next_entry() was incorrectly
being updated when the size did not change. The temp buffer size should only
be updated when it is reallocated.
This is mostly an issue when used with ftrace_dump(). That's because
ftrace_dump() can not allocate a new buffer, and instead uses a temporary
buffer with a fix size. But the variable that keeps track of that size is
incorrectly updated with each call, and it could fall into the path that
would try to reallocate the buffer and produce a warning.
------------[ cut here ]------------
WARNING: CPU: 1 PID: 1601 at kernel/trace/trace.c:3548
trace_find_next_entry+0xd0/0xe0
Modules linked in [..]
CPU: 1 PID: 1601 Comm: bash Not tainted 5.9.0-rc5-test+ #521
Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03
07/14/2016
RIP: 0010:trace_find_next_entry+0xd0/0xe0
Code: 40 21 00 00 4c 89 e1 31 d2 4c 89 ee 48 89 df e8 c6 9e ff ff 89 ab 54
21 00 00 5b 5d 41 5c 41 5d c3 48 63 d5 eb bf 31 c0 eb f0 <0f> 0b 48 63 d5 eb
b4 66 0f 1f 84 00 00 00 00 00 53 48 8d 8f 60 21
RSP: 0018:ffff95a4f2e8bd70 EFLAGS: 00010046
RAX: ffffffff96679fc0 RBX: ffffffff97910de0 RCX: ffffffff96679fc0
RDX: ffff95a4f2e8bd98 RSI: ffff95a4ee321098 RDI: ffffffff97913000
RBP: 0000000000000018 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000046 R12: ffff95a4f2e8bd98
R13: 0000000000000000 R14: ffff95a4ee321098 R15: 00000000009aa301
FS: 00007f8565484740(0000) GS:ffff95a55aa40000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055876bd43d90 CR3: 00000000b76e6003 CR4: 00000000001706e0
Call Trace:
trace_print_lat_context+0x58/0x2d0
? cpumask_next+0x16/0x20
print_trace_line+0x1a4/0x4f0
ftrace_dump.cold+0xad/0x12c
__handle_sysrq.cold+0x51/0x126
write_sysrq_trigger+0x3f/0x4a
proc_reg_write+0x53/0x80
vfs_write+0xca/0x210
ksys_write+0x70/0xf0
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f8565579487
Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa
64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff
77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
RSP: 002b:00007ffd40707948 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f8565579487
RDX: 0000000000000002 RSI: 000055876bd74de0 RDI: 0000000000000001
RBP: 000055876bd74de0 R08: 000000000000000a R09: 0000000000000001
R10: 000055876bdec280 R11: 0000000000000246 R12: 0000000000000002
R13: 00007f856564a500 R14: 0000000000000002 R15: 00007f856564a700
irq event stamp: 109958
---[ end trace 7aab5b7e51484b00 ]---
Not only fix the updating of the temp buffer, but also do not free the temp
buffer before a new buffer is allocated (there's no reason to not continue
to use the current temp buffer if an allocation fails).
Cc: stable@vger.kernel.org
Fixes: 8e99cf91b9 ("tracing: Do not allocate buffer in trace_find_next_entry() in atomic")
Reported-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When returning or breaking early from a
`for_each_available_child_of_node()` loop, we need to explicitly call
`of_node_put()` on the child node to possibly release the node.
Fixes: 506d2e317a ("iio: adc: Add driver support for AD7292")
Signed-off-by: Nuno Sá <nuno.sa@analog.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200925091045.302-2-nuno.sa@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
When returning or breaking early from a
`for_each_available_child_of_node()` loop, we need to explicitly call
`of_node_put()` on the child node to possibly release the node.
Fixes: f110f3188e ("iio: temperature: Add support for LTC2983")
Signed-off-by: Nuno Sá <nuno.sa@analog.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200925091045.302-1-nuno.sa@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Replace commas with semicolons. What is done is essentially described by
the following Coccinelle semantic patch (http://coccinelle.lip6.fr/):
// <smpl>
@@ expression e1,e2; @@
e1
-,
+;
e2
... when any
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Reviewed-by: David Lechner <david@lechnology.com>
Link: https://lore.kernel.org/r/1601233948-11629-16-git-send-email-Julia.Lawall@inria.fr
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
For some embedded systems, a workflow involving external kernel modules
that implement IIO devices is more practical than working with in-tree
sources.
Kconfig symbols without any titles do not show up in menuconfig, and as
such are more difficult to configure granularly, as they need to be
selected by potentially unused/un-needed drivers.
This change adds a title to the IIO_TRIGGERED_BUFFER Kconfig symbol.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20200924111758.196367-4-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
For some embedded systems, a workflow involving external kernel modules
that implement IIO devices is more practical than working with in-tree
sources.
Kconfig symbols without any titles do not show up in menuconfig, and as
such are more difficult to configure granularly, as they need to be
selected by potentially unused/un-needed drivers.
Albeit, the IIO_TRIGGERED_EVENT is used by a single mainline driver, this
could allow for some out-of-tree drivers to use this kmod.
This change adds a title to the IIO_TRIGGERED_EVENT Kconfig symbol.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20200924111758.196367-3-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
For some embedded systems, a workflow involving external kernel modules
that implement IIO devices is more practical than working with in-tree
sources.
Kconfig symbols without any titles do not show up in menuconfig, and as
such are more difficult to configure granularly, as they need to be
selected by potentially unused/un-needed drivers.
This change adds titles to the IIO DMA Kconfig symbols to address this.
This change also updates DMAengine -> DMAEngine, which is the
correct/nitpick-y name of the framework.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20200924111758.196367-2-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The intent here is to minimize the use of iio_buffer_set_attrs(). Since we
are planning to add support for multiple IIO buffers per IIO device, the
issue has to do with:
1. Accessing 'indio_dev->buffer' directly (as is done with
'iio_buffer_set_attrs(indio_dev->buffer, <attrs>)').
2. The way that the buffer attributes would get handled or expanded when
there are more buffers per IIO device. Current a sysfs kobj_type expands
into a 'device' object that expands into an 'iio_dev' object.
We will need to change this, so that the sysfs attributes for IIO
buffers expand into IIO buffers at some point.
Right now, the current IIO framework works fine for the
'1 IIO device == 1 IIO buffer' case (that is now).
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Link: https://lore.kernel.org/r/20200923130339.997902-1-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Add entries for the AD9434 & AD9265 high-speed ADCs which are supported by
the 'ad9467' driver.
Better describe the family of ADCs similar to AD9467 in the description.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20200924080518.96410-5-alexandru.ardelean@analog.com
The AD9265 is a 16-bit, 125 MSPS analog-to-digital converter (ADC). The
AD9265 is designed to support communications applications where high
performance combined with low cost, small size, and versatility is
desired.
The ADC core features a multistage, differential pipelined architecture
with integrated output error correction logic to provide 16-bit accuracy at
125 MSPS data rates and guarantees no missing codes over the full operating
temperature range.
The ADC features a wide bandwidth differential sample-and-hold analog input
amplifier supporting a variety of user-selectable input ranges. It is
suitable for multiplexed systems that switch full-scale voltage levels in
successive channels and for sampling single-channel inputs at frequencies
well beyond the Nyquist rate. Combined with power and cost savings over
previously available ADCs, the AD9265 is suitable for applications in
communications, instrumentation and medical imaging.
Link: https://www.analog.com/media/en/technical-documentation/data-sheets/AD9434.pdf
The driver supports the same register set as the AD9467, so the support for
this chip is added to the 'ad9467' driver.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20200924080518.96410-4-alexandru.ardelean@analog.com
The AD9434 is a 12-bit monolithic sampling analog-to-digital converter
(ADC) optimized for high performance, low power, and ease of use. The part
operates at up to a 500 MSPS conversion rate and is optimized for
outstanding dynamic performance in wideband carrier and broadband systems.
All necessary functions, including a sample-and-hold and voltage reference,
are included on the chip to provide a complete signal conversion solution.
The VREF pin can be used to monitor the internal reference or provide an
external voltage reference (external reference mode must be enabled through
the SPI port).
The ADC requires a 1.8 V analog voltage supply and a differential clock
for full performance operation. The digital outputs are LVDS (ANSI-644)
compatible and support twos complement, offset binary format, or Gray code.
A data clock output is available for proper output data timing.
Link: https://www.analog.com/media/en/technical-documentation/data-sheets/AD9434.pdf
The driver supports the same register set as the AD9467, so the support for
this chip is added to the 'ad9467' driver.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20200924080518.96410-3-alexandru.ardelean@analog.com
There are 2 chip constants that can be added to the chip-info part. The
default output-mode and the VREF mask.
When adding new chips to this driver, these can be easily omitted, because
these also need to be updated in 2 switch statements.
However, if adding them in the chip-info constants, they are updated in a
single place and propagated in both switch statements.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20200924080518.96410-2-alexandru.ardelean@analog.com
This is to encourage the use of devm_iio_dmaengine_buffer_alloc().
Currently the managed version of the DMAEngine buffer alloc is the only
function used from this part of the framework.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20200923121810.944075-1-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Make use of devm_platform_get_and_ioremap_resource() provided by
driver core platform instead of duplicated analogue, dev_err() is
removed because it has been done in devm_ioremap_resource().
Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
Link: https://lore.kernel.org/r/20200918083142.32816-1-bobo.shaobowang@huawei.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Make use of devm_platform_get_and_ioremap_resource() provided by
driver core platform instead of duplicated analogue.
Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
Link: https://lore.kernel.org/r/20200918082837.32610-1-bobo.shaobowang@huawei.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Use PLATFORM_DEVID_NONE define instead of "-1" value because:
- it brings some meaning,
- it might point attention why auto device ID was not used.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20200921204939.20341-1-krzk@kernel.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
There are no in-tree users of the platform data for this driver, so
remove it and convert the driver to use device tree instead.
Signed-off-by: Michael Auchter <michael.auchter@ni.com>
Link: https://lore.kernel.org/r/20200922144422.542669-1-michael.auchter@ni.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Though we know that the iio_device_unregister_eventset() call is followed
by the free-ing of the IIO device object, we should not make this
assumption in the iio_device_unregister_eventset() function. It should
allow for the clean unregistering of the event-set, allowing a re-register
should we decide to implement this at some point later.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20200921103156.194748-2-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
With the recent 'iio_dev_opaque' variable name, these two functions are
looking a bit ugly.
This change uses an 'ev_int' variable for the
iio_device_{un}register_eventset functions to make the code a little easier
to read.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20200921103156.194748-1-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This binding is non trivial due to the range of different parts
supported having several subtle quirks. Martin has helped
clarify some of them.
Note, I haven't restricted the amlogic,hhi-sysctrl to only
be present on the relevant parts if nvmem stuff also is, but
it would seem to be rather odd if it were otherwise.
Perhaps we look to make this binding more restrictive at a later date.
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20200920135436.199003-2-jic23@kernel.org
Originally I intended to merge a dedicated Baikal-T1 System Boot SPI
Controller driver into the kernel and leave the DW APB SSI driver
untouched. But after a long discussion (see the link at the bottom of the
letter) Mark and Andy persuaded me to integrate what we developed there
into the DW APB SSI core driver to be useful for another controllers,
which may have got the same peculiarities/problems as ours:
- No IRQ.
- No DMA.
- No GPIO CS, so a native CS is utilized.
- small Tx/Rx FIFO depth.
- Automatic CS assertion/de-assertion.
- Slow system bus.
All of them have been fixed in the framework of this patchset in some
extent at least for the SPI memory operations. As I expected it wasn't
that easy and the integration took that many patches as you can see from
the subject. Though some of them are mere cleanups or weakly related with
the subject fixes, but we just couldn't leave the code as is at some
places since we were working with the DW APB SSI driver anyway. Here is
what we did to fix the original DW APB SSI driver, to make it less messy.
First two patches are just cleanups to simplify the DW APB SSI device
initialization a bit. We suggest to discard the IRQ threshold macro as
unused and use a ternary operator to initialize the set_cs callback
instead of assigning-and-updating it.
Then we've discovered that the n_bytes field of the driver private data is
used by the DW APB SSI IRQ handler, which requires it to be initialized
before the SMP memory barrier and to be visible from another CPUs. Speaking
about the SMP memory barrier. Having one right after the shared resources
initialization is enough and there is no point in using the spin-lock to
protect the Tx/Rx buffer pointers. The protection functionality is
redundant there by the driver design. (Though I have a doubt whether the
SMP memory barrier is also required there because the normal IO-methods
like readl/writel implies a full memory barrier. So any memory operations
performed before them are supposed to be seen by devices and another CPUs.
See the patch log for details of my concern.)
Thirdly we've found out that there is some confusion in the IRQs
masking/unmasking/clearing in the SPI-transfer procedure. Multiple interrupts
are unmasked on the SPI-transfer initialization, but just TXEI is only
masked back on completion. Similarly IRQ status isn't cleared on the
controller reset, which actually makes the reset being not full and errors
prone in the controller probe procedure.
Another very important optimization is using the IO-relaxed accessors in
the dw_read_io_reg()/dw_write_io_reg() methods. Since the Tx/Rx FIFO data
registers are the most frequently accessible controller resource, using
relaxed accessors there will significantly improve the data read/write
performance. At least on Baikal-T1 SoC such modification opens up a way to
have the DW APB SSI controller working with higher SPI bus speeds, than
without it.
Fifthly we've made an effort to cleanup the code using the SPI-device
private data - chip_data. We suggest to remove the chip type from there
since it isn't used and isn't implemented right anyway. Then instead of
having a bus speed, clock divider, transfer mode preserved there, and
recalculating the CR0 fields of the SPI-device-specific phase, polarity
and frame format each time the SPI transfer is requested, we can save it
in the chip_data instance. By doing so we'll make that structure finally
used as it was supposed to by design (see the spi-fsl-dspi.c, spi-pl022.c,
spi-pxa2xx.c drivers for examples).
Sixthly instead of having the SPI-transfer specific CR0-update callback,
we suggest to implement the DW APB SSI controller capabilities approach.
By doing so we can now inject the vendor-specific peculiarities in
different parts of the DW APB SSI core driver (which is required to
implement both SPI-transfers and the SPI memory operations). This will
also make the code less confusing like defining a callback in the core
driver, setting it up in the glue layer, then calling it from the core
driver again. Seeing the small capabilities implementation embedded
in-situ is more readable than tracking the callbacks assignments. This
will concern the CS-override, Keembay master setup, DW SSI-specific CR0
registers layout capabilities.
Seventhly since there are going to be two types of the transfers
implemented in the DW APB SSI core driver, we need a common method to set
the controller configuration like, Tx/Rx-mode, bus speed, data frame size
and number of data frames to read in case of the memory operations. So we
just detached the corresponding code from the SPI-transfer-one method and
made it to be a part of the new dw_spi_update_config() function, which is
former update_cr0(). Note that the new method will be also useful for the
glue drivers, which due to the hardware design need to create their own
memory operations (for instance, for the dirmap-operations provided in the
Baikal-T System Boot SPI controller driver).
Eighthly it is the data IO procedure and IRQ-based SPI-transfer
implementation refactoring. The former one will look much simpler if the
buffers initial pointers and the buffers length data utilized instead of
the Tx/Rx buffers start and end pointers. The later one currently lacks of
valid execution at the final stage of the SPI-transfer. So if there is no
data left to send, but there is still data which needs to be received, the
Tx FIFO Empty IRQ will constantly happen until all of the requested
inbound data is received. So we suggest to fix that by taking the Rx FIFO
Empty IRQ into account.
Ninthly it's potentially errors prone to enable the DW APB SSI interrupts
before enabling the chip. It specifically concerns a case if for some
reason the DW APB SSI IRQs handler is executed before the controller is
enabled. That will cause a part of the outbound data loss. So we suggest
to reverse the order.
Tenthly in order to be able to pre-initialize the Tx FIFO with data and
only the start the SPI memory operations we need to have any CS
de-activated. We'll fulfil that requirement by explicitly clearing the CS
on the SPI transfer completion and at the explicit controller reset.
Then seeing all the currently available and potentially being created
types of the SPI transfers need to perform the DW APB SSI controller
status register check and the errors handler procedure, we've created a
common method for all of them.
Eleventhly if before we've mostly had a series of fixups, cleanups and
refactorings, here we've finally come to the new functionality
implementation. It concerns the poll-based transfer (as Baikal-T1 System
Boot SPI controller lacks a dedicated IRQ lane connected) and the SPI
memory operations implementation. If the former feature is pretty much
straightforward (see the patch log for details), the later one is a bit
tricky. It's based on the EEPROM-read (write-then-read) and the Tx-only
modes of the DW APB SSI controller, which as performing the automatic data
read and write let's us to implement the faster IO procedure than using
the Tx-Rx-mode-based approach. Having the memory-operations implemented
that way is the best thing we can currently do to provide the errors-less
SPI transfers to SPI devices with native CS attached.
Note the approach utilized here to develop the SPI memory operations can
be also used to create the "automatic CS toggle problem"-free(ish) SPI
transfers (combine SPI-message transfers into two buffers, disable
interrupts, push-pull the combined data). But we don't provide a solution
in the framework of this patchset. It is a matter of a dedicated one,
which we currently don't intend to spend our time on.
Finally at the closure of the this patchset you'll find patches, which
provide the Baikal-T1-specific DW APB SSI controllers support. The SoC has
got three SPI controllers. Two of them are pretty much normal DW APB SSI
interfaces: with IRQ, DMA, FIFOs of 64 words depth, 4x CSs. But the third
one as being a part of the Baikal-T1 System Boot Controller has got a very
limited resources: no IRQ, no DMA, only a single native chip-select and
Tx/Rx FIFOs with just 8 words depth available. In order to provide a
transparent initial boot code execution the System Boot SPI Controller is
also utilized by an vendor-specific IP-block, which exposes an SPI flash
memory direct mapping interface. Please see the corresponding patch for
details.
Link: https://lore.kernel.org/linux-spi/20200508093621.31619-1-Sergey.Semin@baikalelectronics.ru/
[1] "LINUX KERNEL MEMORY BARRIERS", Documentation/memory-barriers.txt,
Section "KERNEL I/O BARRIER EFFECTS"
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Cc: Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Lars Povlsen <lars.povlsen@microchip.com>
Cc: wuxu.wu <wuxu.wu@huawei.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-spi@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Serge Semin (30):
spi: dw: Discard IRQ threshold macro
spi: dw: Use ternary op to init set_cs callback
spi: dw: Initialize n_bytes before the memory barrier
Revert: spi: spi-dw: Add lock protect dw_spi rx/tx to prevent
concurrent calls
spi: dw: Clear IRQ status on DW SPI controller reset
spi: dw: Disable all IRQs when controller is unused
spi: dw: Use relaxed IO-methods to access FIFOs
spi: dw: Discard DW SSI chip type storages
spi: dw: Convert CS-override to DW SPI capabilities
spi: dw: Add KeemBay Master capability
spi: dw: Add DWC SSI capability
spi: dw: Detach SPI device specific CR0 config method
spi: dw: Update SPI bus speed in a config function
spi: dw: Simplify the SPI bus speed config procedure
spi: dw: Update Rx sample delay in the config function
spi: dw: Add DW SPI controller config structure
spi: dw: Refactor data IO procedure
spi: dw: Refactor IRQ-based SPI transfer procedure
spi: dw: Perform IRQ setup in a dedicated function
spi: dw: Unmask IRQs after enabling the chip
spi: dw: Discard chip enabling on DMA setup error
spi: dw: De-assert chip-select on reset
spi: dw: Explicitly de-assert CS on SPI transfer completion
spi: dw: Move num-of retries parameter to the header file
spi: dw: Add generic DW SSI status-check method
spi: dw: Add memory operations support
spi: dw: Introduce max mem-ops SPI bus frequency setting
spi: dw: Add poll-based SPI transfers support
dt-bindings: spi: dw: Add Baikal-T1 SPI Controllers
spi: dw: Add Baikal-T1 SPI Controller glue driver
.../bindings/spi/snps,dw-apb-ssi.yaml | 33 +-
drivers/spi/Kconfig | 29 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-dw-bt1.c | 339 +++++++++
drivers/spi/spi-dw-core.c | 642 ++++++++++++++----
drivers/spi/spi-dw-dma.c | 16 +-
drivers/spi/spi-dw-mmio.c | 36 +-
drivers/spi/spi-dw.h | 85 ++-
8 files changed, 960 insertions(+), 221 deletions(-)
create mode 100644 drivers/spi/spi-dw-bt1.c
--
2.27.0
There is no point in having the commit 19b61392c5 ("spi: spi-dw: Add
lock protect dw_spi rx/tx to prevent concurrent calls") applied. The
commit author made an assumption that the problem with the rx data
mismatch was due to the lack of the data protection. While most likely it
was caused by the lack of the memory barrier. So having the
commit bfda044533 ("spi: dw: use "smp_mb()" to avoid sending spi data
error") applied would be enough to fix the problem.
Indeed the spin unlock operation makes sure each memory operation issued
before the release will be completed before it's completed. In other words
it works as an implicit one way memory barrier. So having both smp_mb()
and the spin_unlock_irqrestore() here is just redundant. One of them would
be enough. It's better to leave the smp_mb() since the Tx/Rx buffers
consistency is provided by the data transfer algorithm implementation:
first we initialize the buffers pointers, then make sure the assignments
are visible by the other CPUs by calling the smp_mb(), only after that
enable the interrupt, which handler uses the buffers.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200920112914.26501-5-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
In a further commit we'll have to get rid of the update_cr0() callback and
define a DW SSI capability instead. Since Keem Bay master/slave
functionality is controller by the CTRL0 register bitfield, we need to
first move the master mode selection into the internal corresponding
update_cr0 method, which would be activated by means of the dedicated
DW_SPI_CAP_KEEMBAY_MST capability setup.
Note this will be also useful if the driver will be ever altered to
support the DW SPI slave interface.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200920112914.26501-11-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
There are several vendor-specific versions of the DW SPI controllers,
each of which may have some peculiarities with respect to the original
IP-core. Seeing it has already caused adding flags and a callback into the
DW SPI private data, let's introduce a generic capabilities interface to
tune the generic DW SPI controller driver up in accordance with the
particular controller specifics. It's done by converting a simple
Alpine-specific CS-override capability into the DW SPI controller
capability activated by setting the DW_SPI_CAP_CS_OVERRIDE flag.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200920112914.26501-10-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
Keeping SPI peripheral devices type is pointless since first it hasn't
been functionally utilized by any of the client drivers/code and second it
won't work for Microwire type at the very least. Moreover there is no
point in setting up the type by means of the chip-data in the modern
kernel. The peripheral devices with specific interface type need to be
detected in order to activate the corresponding frame format. It most
likely will require some peripheral device specific DT property or
whatever to find out the interface protocol. So let's remove the serial
interface type fields from the DW APB SSI controller and the SPI
peripheral device private data.
Note we'll preserve the explicit SSI_MOTO_SPI interface type setting up to
signify the only currently supported interface protocol.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200920112914.26501-9-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>