commit a500f3bd78 upstream.
The differential channels require writing the channel offset register (COR).
Otherwise they do not work in differential mode.
The configuration of COR is missing in triggered mode.
Fixes: 5e1a1da0f8 ("iio: adc: at91-sama5d2_adc: add hw trigger and buffer support")
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b500c086e4 upstream.
At the moment, reading from in_magn_*_raw in sysfs tends to return
large values around 65000, even though the output of ak8974 is actually
limited to ±32768. This happens because the value is never converted
to the signed 16-bit integer variant.
Add an explicit cast to s16 to fix this.
Fixes: 7c94a8b2ee ("iio: magn: add a driver for AK8974")
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Linus Waleij <linus.walleij@linaro.org>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 29e8c8253d upstream.
Master mode should be disabled when stopping. This mainly impacts
possible other use-case after timer has been stopped. Currently,
master mode remains set (from start routine).
Fixes: 6fb34812c2 ("iio: stm32 trigger: Add support for TRGO2 triggers")
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f2ecf903ef upstream.
Each OSS PCM plugins allocate its internal buffer per pre-calculation
of the max buffer size through the chain of plugins (calling
src_frames and dst_frames callbacks). This works for most plugins,
but the rate plugin might behave incorrectly. The calculation in the
rate plugin involves with the fractional position, i.e. it may vary
depending on the input position. Since the buffer size
pre-calculation is always done with the offset zero, it may return a
shorter size than it might be; this may result in the out-of-bound
access as spotted by fuzzer.
This patch addresses those possible buffer overflow accesses by simply
setting the upper limit per the given buffer size for each plugin
before src_frames() and after dst_frames() calls.
Reported-by: syzbot+e1fe9f44fb8ecf4fb5dd@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/000000000000b25ea005a02bcf21@google.com
Link: https://lore.kernel.org/r/20200309082148.19855-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 75d7676ead upstream.
We have been receiving bug reports that ethernet connections over
RTL8153 based ethernet adapters stops working after a while with
errors like these showing up in dmesg when the ethernet stops working:
[12696.189484] r8152 6-1:1.0 enp10s0u1: Tx timeout
[12702.333456] r8152 6-1:1.0 enp10s0u1: Tx timeout
[12707.965422] r8152 6-1:1.0 enp10s0u1: Tx timeout
This has been reported on Dell WD15 docks, Belkin USB-C Express Dock 3.1
docks and with generic USB to ethernet dongles using the RTL8153
chipsets. Some users have tried adding usbcore.quirks=0bda:8153:k to
the kernel commandline and all users who have tried this report that
this fixes this.
Also note that we already have an existing NO_LPM quirk for the RTL8153
used in the Microsoft Surface Dock (where it uses a different usb-id).
This commit adds a NO_LPM quirk for the generic Realtek RTL8153
0bda:8153 usb-id, fixing the Tx timeout errors on these devices.
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=198931
Cc: stable@vger.kernel.org
Cc: russianneuromancer@ya.ru
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20200313120708.100339-1-hdegoede@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 14afc59361 ]
The bfq_find_set_group() function takes as input a blkcg (which represents
a cgroup) and retrieves the corresponding bfq_group, then it updates the
bfq internal group hierarchy (see comments inside the function for why
this is needed) and finally it returns the bfq_group.
In the hierarchy update cycle, the pointer holding the correct bfq_group
that has to be returned is mistakenly used to traverse the hierarchy
bottom to top, meaning that in each iteration it gets overwritten with the
parent of the current group. Since the update cycle stops at root's
children (depth = 2), the overwrite becomes a problem only if the blkcg
describes a cgroup at a hierarchy level deeper than that (depth > 2). In
this case the root's child that happens to be also an ancestor of the
correct bfq_group is returned. The main consequence is that processes
contained in a cgroup at depth greater than 2 are wrongly placed in the
group described above by BFQ.
This commits fixes this problem by using a different bfq_group pointer in
the update cycle in order to avoid the overwrite of the variable holding
the original group reference.
Reported-by: Kwon Je Oh <kwonje.oh2@gmail.com>
Signed-off-by: Carlo Nonato <carlo.nonato95@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit a0275dfc82 ]
[Why]
Swath sizes are being calculated incorrectly. The horizontal swath size
should be the product of block height, viewport width, and bytes per
element, but the calculation uses viewport height instead of width. The
vertical swath size is similarly incorrectly calculated. The effect of
this is that we report the wrong DCC caps.
[How]
Use viewport width in the horizontal swath size calculation and viewport
height in the vertical swath size calculation.
Signed-off-by: Josip Pavic <Josip.Pavic@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0cff8bff7a ]
The compiler uses the PIC-relative method to access static variables
instead of GOT when the code model is PIC. Therefore, the limitation of
the access range from the instruction to the symbol address is +-2GB.
Under this circumstance, the kernel cannot load a kernel module if this
module has static per-CPU symbols declared by DEFINE_PER_CPU(). The reason
is that kernel relocates the .data..percpu section of the kernel module to
the end of kernel's .data..percpu. Hence, the distance between the per-CPU
symbols and the instruction will exceed the 2GB limits. To solve this
problem, the kernel should place the loaded module in the memory area
[&_end-2G, VMALLOC_END].
Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Suggested-by: Alexandre Ghiti <alex@ghiti.fr>
Suggested-by: Anup Patel <anup@brainfault.org>
Tested-by: Alexandre Ghiti <alex@ghiti.fr>
Tested-by: Carlos de Paula <me@carlosedp.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 248aa2645a ]
In cases where dec_in_flight() has to requeue the integrity_bio_wait
work to transfer the rest of the data, the bio's __bi_remaining might
already have been decremented to 0, e.g.: if bio passed to underlying
data device was split via blk_queue_split().
Use dm_bio_{record,restore} rather than effectively open-coding them in
dm-integrity -- these methods now manage __bi_remaining too.
Depends-on: f7f0b057a9c1 ("dm bio record: save/restore bi_end_io and bi_integrity")
Reported-by: Daniel Glöckner <dg@emlix.com>
Suggested-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1b17159e52 ]
Also, save/restore __bi_remaining in case the bio was used in a
BIO_CHAIN (e.g. due to blk_queue_split).
Suggested-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3745488e9d ]
altera_get_note is called from altera_init, where key is kzalloc(33).
When the allocation functions are annotated to allow the compiler to see
the sizes of objects, and with FORTIFY_SOURCE, we see:
In file included from drivers/misc/altera-stapl/altera.c:14:0:
In function ‘strlcpy’,
inlined from ‘altera_init’ at drivers/misc/altera-stapl/altera.c:2189:5:
include/linux/string.h:378:4: error: call to ‘__write_overflow’ declared with attribute error: detected write beyond size of object passed as 1st parameter
__write_overflow();
^~~~~~~~~~~~~~~~~~
That refers to this code in altera_get_note:
if (key != NULL)
strlcpy(key, &p[note_strings +
get_unaligned_be32(
&p[note_table + (8 * i)])],
length);
The error triggers because the length of 'key' is 33, but the copy
uses length supplied as the 'length' parameter, which is always
256. Split the size parameter into key_len and val_len, and use the
appropriate length depending on what is being copied.
Detected by compiler error, only compile-tested.
Cc: "Igor M. Liplianin" <liplianin@netup.ru>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Link: https://lore.kernel.org/r/20200120074344.504-2-dja@axtens.net
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/202002251042.D898E67AC@keescook
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3ba52ad55b ]
Fix bogus NULL checks on the return value of acpi_cpu_get_madt_gicc()
by checking for a 0 'gicc->performance_interrupt' value instead.
Signed-off-by: Liguang Zhang <zhangliguang@linux.alibaba.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c0fd99d659 ]
Writing to the built-in strings arrays doesn't work if driver is loaded
as kernel module. This is also considered as a bad pattern. Fix this by
adding a call to clk_get() with legacy clock name. This fixes following
kernel oops if driver is loaded as module:
Unable to handle kernel paging request at virtual address bf047978
pgd = (ptrval)
[bf047978] *pgd=59344811, *pte=5903c6df, *ppte=5903c65f
Internal error: Oops: 80f [#1] SMP ARM
Modules linked in: mc exynosdrm(+) analogix_dp rtc_s3c exynos_ppmu i2c_gpio
CPU: 1 PID: 212 Comm: systemd-udevd Not tainted 5.6.0-rc2-next-20200219 #326
videodev: Linux video capture interface: v2.00
Hardware name: Samsung Exynos (Flattened Device Tree)
PC is at exynos_dsi_probe+0x1f0/0x384 [exynosdrm]
LR is at exynos_dsi_probe+0x1dc/0x384 [exynosdrm]
...
Process systemd-udevd (pid: 212, stack limit = 0x(ptrval))
...
[<bf03cf14>] (exynos_dsi_probe [exynosdrm]) from [<c09b1ca0>] (platform_drv_probe+0x6c/0xa4)
[<c09b1ca0>] (platform_drv_probe) from [<c09afcb8>] (really_probe+0x210/0x350)
[<c09afcb8>] (really_probe) from [<c09aff74>] (driver_probe_device+0x60/0x1a0)
[<c09aff74>] (driver_probe_device) from [<c09b0254>] (device_driver_attach+0x58/0x60)
[<c09b0254>] (device_driver_attach) from [<c09b02dc>] (__driver_attach+0x80/0xbc)
[<c09b02dc>] (__driver_attach) from [<c09ade00>] (bus_for_each_dev+0x68/0xb4)
[<c09ade00>] (bus_for_each_dev) from [<c09aefd8>] (bus_add_driver+0x130/0x1e8)
[<c09aefd8>] (bus_add_driver) from [<c09b0d64>] (driver_register+0x78/0x110)
[<c09b0d64>] (driver_register) from [<bf038558>] (exynos_drm_init+0xe8/0x11c [exynosdrm])
[<bf038558>] (exynos_drm_init [exynosdrm]) from [<c0302fa8>] (do_one_initcall+0x50/0x220)
[<c0302fa8>] (do_one_initcall) from [<c03dd02c>] (do_init_module+0x60/0x210)
[<c03dd02c>] (do_init_module) from [<c03dbf44>] (load_module+0x1c0c/0x2310)
[<c03dbf44>] (load_module) from [<c03dc85c>] (sys_finit_module+0xac/0xbc)
[<c03dc85c>] (sys_finit_module) from [<c0301000>] (ret_fast_syscall+0x0/0x54)
Exception stack(0xd979bfa8 to 0xd979bff0)
...
---[ end trace db16efe05faab470 ]---
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0a9d1e3f3f ]
Properly propagate error value from devm_regulator_bulk_get() and don't
confuse user with meaningless warning about failure in getting regulators
in case of deferred probe.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5dd8304981 ]
In the public interface for chipselect, there is always an entry
commented as "Dummy generic FIFO entry" pushed down to the fifo right
after the activate/deactivate command. The dummy entry is 0x0,
irregardless if the intention was to activate or deactive the cs. This
causes the cs line to glitch rather than beeing activated in the case
when there was an activate command.
This has been observed on oscilloscope, and have caused problems for at
least one specific flash device type connected to the qspi port. After
the change the glitch is gone and cs goes active when intended.
The reason why this worked before (except for the glitch) was because
when sending the actual data, the CS bits are once again set. Since
most flashes uses mode 0, there is always a half clk period anyway for
cs to clk active setup time. If someone would rely on timing from a
chip_select call to a transfer_one, it would fail though.
It is unknown why the dummy entry was there in the first place, git log
seems to be of no help in this case. The reference manual gives no
indication of the necessity of this. In fact the lower 8 bits are a
setup (or hold in case of deactivate) time expressed in cycles. So this
should not be needed to fulfill any setup/hold timings.
Signed-off-by: Thommy Jakobsson <thommyj@gmail.com>
Reviewed-by: Naga Sureshkumar Relli <naga.sureshkumar.relli@xilinx.com>
Link: https://lore.kernel.org/r/20200224162643.29102-1-thommyj@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 683f65ded6 ]
In some circumstances on Intel LPSS controllers, toggling the LPSS
CS control register doesn't actually cause the CS line to toggle.
This seems to be failure of dynamic clock gating that occurs after
going through a suspend/resume transition, where the controller
is sent through a reset transition. This ruins SPI transactions
that either rely on delay_usecs, or toggle the CS line without
sending data.
Whenever CS is toggled, momentarily set the clock gating register
to "Force On" to poke the controller into acting on CS.
Signed-off-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Evan Green <evgreen@chromium.org>
Link: https://lore.kernel.org/r/20200211223700.110252-1-rajatja@google.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 27f1377465 ]
'dma-ranges' in a PCI bridge node does correctly set dma masks for PCI
devices not described in the DT. Certain DRA7 platforms (e.g., DRA76)
has RAM above 32-bit boundary (accessible with LPAE config) though the
PCIe bridge will be able to access only 32-bits. Add 'dma-ranges'
property in PCIe RC DT nodes to indicate the host bridge can access
only 32 bits.
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit fd4d9c7d0c upstream.
When kmem_cache_alloc_bulk() attempts to allocate N objects from a percpu
freelist of length M, and N > M > 0, it will first remove the M elements
from the percpu freelist, then call ___slab_alloc() to allocate the next
element and repopulate the percpu freelist. ___slab_alloc() can re-enable
IRQs via allocate_slab(), so the TID must be bumped before ___slab_alloc()
to properly commit the freelist head change.
Fix it by unconditionally bumping c->tid when entering the slowpath.
Cc: stable@vger.kernel.org
Fixes: ebe909e0fd ("slub: improve bulk alloc strategy")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 45939ce292 upstream.
It is possible for a system with an ARMv8 timer to run a 32-bit kernel.
When this happens we will unconditionally have the vDSO code remove the
__vdso_gettimeofday and __vdso_clock_gettime symbols because
cntvct_functional() returns false since it does not match that
compatibility string.
Fixes: ecf99a4391 ("ARM: 8331/1: VDSO initialization, mapping, and synchronization")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ce57785bf9 upstream.
The len used for skb_put_padto is wrong, it need to add len of hdr.
In qrtr_node_enqueue, local variable size_t len is assign with
skb->len, then skb_push(skb, sizeof(*hdr)) will add skb->len with
sizeof(*hdr), so local variable size_t len is not same with skb->len
after skb_push(skb, sizeof(*hdr)).
Then the purpose of skb_put_padto(skb, ALIGN(len, 4)) is to add add
pad to the end of the skb's data if skb->len is not aligned to 4, but
unfortunately it use len instead of skb->len, at this line, skb->len
is 32 bytes(sizeof(*hdr)) more than len, for example, len is 3 bytes,
then skb->len is 35 bytes(3 + 32), and ALIGN(len, 4) is 4 bytes, so
__skb_put_padto will do nothing after check size(35) < len(4), the
correct value should be 36(sizeof(*hdr) + ALIGN(len, 4) = 32 + 4),
then __skb_put_padto will pass check size(35) < len(36) and add 1 byte
to the end of skb's data, then logic is correct.
function of skb_push:
void *skb_push(struct sk_buff *skb, unsigned int len)
{
skb->data -= len;
skb->len += len;
if (unlikely(skb->data < skb->head))
skb_under_panic(skb, len, __builtin_return_address(0));
return skb->data;
}
function of skb_put_padto
static inline int skb_put_padto(struct sk_buff *skb, unsigned int len)
{
return __skb_put_padto(skb, len, true);
}
function of __skb_put_padto
static inline int __skb_put_padto(struct sk_buff *skb, unsigned int len,
bool free_on_error)
{
unsigned int size = skb->len;
if (unlikely(size < len)) {
len -= size;
if (__skb_pad(skb, len, free_on_error))
return -ENOMEM;
__skb_put(skb, len);
}
return 0;
}
Signed-off-by: Carl Huang <cjhuang@codeaurora.org>
Signed-off-by: Wen Gong <wgong@codeaurora.org>
Cc: Doug Anderson <dianders@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 515db266a9 upstream.
If device_link_add() is called for a consumer/supplier pair with an
existing device link between them and the existing link's type is
not in agreement with the flags passed to that function by its
caller, NULL will be returned. That is seriously inconvenient,
because it forces the callers of device_link_add() to worry about
what others may or may not do even if that is not relevant to them
for any other reasons.
It turns out, however, that this limitation can be made go away
relatively easily.
The underlying observation is that if DL_FLAG_STATELESS has been
passed to device_link_add() in flags for the given consumer/supplier
pair at least once, calling either device_link_del() or
device_link_remove() to release the link returned by it should work,
but there are no other requirements associated with that flag. In
turn, if at least one of the callers of device_link_add() for the
given consumer/supplier pair has not passed DL_FLAG_STATELESS to it
in flags, the driver core should track the status of the link and act
on it as appropriate (ie. the link should be treated as "managed").
This means that DL_FLAG_STATELESS needs to be set for managed device
links and it should be valid to call device_link_del() or
device_link_remove() to drop references to them in certain
sutiations.
To allow that to happen, introduce a new (internal) device link flag
called DL_FLAG_MANAGED and make device_link_add() set it automatically
whenever DL_FLAG_STATELESS is not passed to it. Also make it take
additional references to existing device links that were previously
stateless (that is, with DL_FLAG_STATELESS set and DL_FLAG_MANAGED
unset) and will need to be managed going forward and initialize
their status (which has been DL_STATE_NONE so far).
Accordingly, when a managed device link is dropped automatically
by the driver core, make it clear DL_FLAG_MANAGED, reset the link's
status back to DL_STATE_NONE and drop the reference to it associated
with DL_FLAG_MANAGED instead of just deleting it right away (to
allow it to stay around in case it still needs to be released
explicitly by someone).
With that, since setting DL_FLAG_STATELESS doesn't mean that the
device link in question is not managed any more, replace all of the
status-tracking checks against DL_FLAG_STATELESS with analogous
checks against DL_FLAG_MANAGED and update the documentation to
reflect these changes.
While at it, make device_link_add() reject flags that it does not
recognize, including DL_FLAG_MANAGED.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Saravana Kannan <saravanak@google.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Review-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/2305283.AStDPdUUnE@kreacher
Signed-off-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e7dd40105a upstream.
Add a new device link flag, DL_FLAG_AUTOPROBE_CONSUMER, to request the
driver core to probe for a consumer driver automatically after binding
a driver to the supplier device on a persistent managed device link.
As unbinding the supplier driver on a managed device link causes the
consumer driver to be detached from its device automatically, this
flag provides a complementary mechanism which is needed to address
some "composite device" use cases.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 72175d4ea4 upstream.
Even though stateful device links are managed by the driver core in
principle, their creators are allowed and sometimes even expected
to drop references to them via device_link_del() or
device_link_remove(), but that doesn't really play well with the
"persistent" link concept.
If "persistent" managed device links are created from driver
probe callbacks, device_link_add() called to do that will take a
new reference on the link each time the callback runs and those
references will never be dropped, which kind of isn't nice.
This issues arises because of the link reference counting carried
out by device_link_add() for existing links, but that is only done to
avoid deleting device links that may still be necessary, which
shouldn't be a concern for managed (stateful) links. These device
links are managed by the driver core and whoever creates one of them
will need it at least as long as until the consumer driver is detached
from its device and deleting it may be left to the driver core just
fine.
For this reason, rework device_link_add() to apply the reference
counting to stateless links only and make device_link_del() and
device_link_remove() drop references to stateless links only too.
After this change, if called to add a stateful device link for
a consumer-supplier pair for which a stateful device link is
present already, device_link_add() will return the existing link
without incrementing its reference counter. Accordingly,
device_link_del() and device_link_remove() will WARN() and do
nothing when called to drop a reference to a stateful link. Thus,
effectively, all stateful device links will be owned by the driver
core.
In addition, clean up the handling of the link management flags,
DL_FLAG_AUTOREMOVE_CONSUMER and DL_FLAG_AUTOREMOVE_SUPPLIER, so that
(a) they are never set at the same time and (b) if device_link_add()
is called for a consumer-supplier pair with an existing stateful link
between them, the flags of that link will be combined with the flags
passed to device_link_add() to ensure that the life time of the link
is sufficient for all of the callers of device_link_add() for the
same consumer-supplier pair.
Update the device_link_add() kerneldoc comment to reflect the
above changes.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
