Simplify signature before further code reshuffling.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220919175721.354679-6-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Start regrouping functionality in high-level functions.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220919175721.354679-5-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

These two steps can and should be done before starting up the clock
and the bus operation. This is a first step before re-grouping
functionality in well-defined callbacks.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220919175721.354679-4-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

We already use devm_ for memory allocation but not for component/DAI
registration. The resource management can be based on devm_ in all
cases.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220919175721.354679-3-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

The call to intel_register_dai() may fail because of memory allocation
issues or problems reported by the ASoC core. In all cases, when a
error is thrown the component is not registered, it's invalid to
unregister it.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220919175721.354679-2-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

There's no need to goto an exit label to return from cdns_xfer_msg().
It doesn't do any cleanup, only a return statement.

Replace the gotos with returns.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20220917154822.690472-2-rf@opensource.cirrus.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

_cdns_xfer_msg() returns an sdw_command_response value, not a
negative error code.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20220917154822.690472-1-rf@opensource.cirrus.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

_cdns_xfer_msg() must add the fragment offset to msg->addr to get the
base target address of each FIFO chunk. Otherwise every chunk will
be written to the first 32 register addresses.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20220917123517.229153-1-rf@opensource.cirrus.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

for_each_set_bit() gives the bit-number counting from 0 (LSbit==0).
When processing INTSTAT2, bit 0 is DP4 so the port number is (bit + 4).
Likewise for INTSTAT3 bit 0 is DP11 so port number is (bit + 11).
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20220917140256.689678-1-rf@opensource.cirrus.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Device0 can not be in alert status. And for consistency reasons do not
send status of device0 to core.
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20220916135352.19114-2-srinivas.kandagatla@linaro.orgSigned-off-by: Vinod Koul <vkoul@kernel.org>

By default autoenumeration is enabled on QCom SoundWire controller
which means the core should not be dealing with device 0 w.r.t enumeration.

During Enumeration if SoundWire core sees status[0] as SDW_SLAVE_ATTACHED and
start programming the device id, however reading DEVID registers return zeros
which does not match to any of the slaves in the list and the core attempts
to park this device to Group 13.  This results in adding SoundWire device
with enumeration address 0:0:0:0

Fix this by not passing device 0 status to SoundWire core.
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20220916135352.19114-1-srinivas.kandagatla@linaro.orgSigned-off-by: Vinod Koul <vkoul@kernel.org>

The buf passed in struct sdw_msg must only be written for a READ,
in that case the RDATA part of the response is the data value of the
register.

For a write command there is no RDATA, and buf should be assumed to
be const and unmodifable. The original caller should not expect its data
buffer to be corrupted by an sdw_nwrite().
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20220916103505.1562210-1-rf@opensource.cirrus.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Only exit sdw_handle_slave_status() right after calling
sdw_program_device_num() if it actually programmed an ID into at
least one device.

sdw_handle_slave_status() should protect itself against phantom
device #0 ATTACHED indications. In that case there is no actual
device still on #0. The early exit relies on there being a status
change to ATTACHED on the reprogrammed device to trigger another
call to sdw_handle_slave_status() which will then handle the status
of all peripherals. If no device was actually programmed with an
ID there won't be a new ATTACHED indication. This can lead to the
status of other peripherals not being handled.

The status passed to sdw_handle_slave_status() is obviously always
from a point of time in the past, and may indicate accumulated
unhandled events (depending how the bus manager operates). It's
possible that a device ID is reprogrammed but the last PING status
captured state just before that, when it was still reporting on
ID #0. Then sdw_handle_slave_status() is called with this PING info,
just before a new PING status is available showing it now on its new
ID. So sdw_handle_slave_status() will receive a phantom report of a
device on #0, but it will not find one.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20220914160248.1047627-6-rf@opensource.cirrus.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

The correct way to handle interrupts is to clear the bits we
are about to handle _before_ handling them. Thus if the condition
then re-asserts during the handling we won't lose it.

This patch changes cdns_update_slave_status_work() to do this.

The previous code cleared the interrupts after handling them.
The problem with this is that when handling enumeration of devices
the ATTACH statuses can be accidentally cleared and so some or all
of the devices never complete their enumeration.

Thus we can have a situation like this:
- one or more devices are reverting to ID #0

- accumulated status bits indicate some devices attached and some
  on ID #0. (Remember: status bits are sticky until they are handled)

- Because of device on #0 sdw_handle_slave_status() programs the
  device ID and exits without handling the other status, expecting
  to get an ATTACHED from this reprogrammed device.

- The device immediately starts reporting ATTACHED in PINGs, which
  will assert its CDNS_MCP_SLAVE_INTSTAT_ATTACHED bit.

- cdns_update_slave_status_work() clears INTSTAT0/1. If the initial
  status had CDNS_MCP_SLAVE_INTSTAT_ATTACHED bit set it will be
  cleared.

- The ATTACHED change for the device has now been lost.

- cdns_update_slave_status_work() clears CDNS_MCP_INT_SLAVE_MASK so
  if the new ATTACHED state had set it, it will be cleared without
  ever having been handled.

Unless there is some other state change from another device to cause
a new interrupt, the ATTACHED state of the reprogrammed device will
never cause an interrupt so its enumeration will not be completed.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20220914160248.1047627-5-rf@opensource.cirrus.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Don't re-enumerate a peripheral on #0 until we have seen and
handled an UNATTACHED notification for that peripheral.

Without this, it is possible for the UNATTACHED status to be missed
and so the slave->status remains at ATTACHED. If slave->status never
changes to UNATTACHED the child driver will never be notified of the
UNATTACH, and the code in sdw_handle_slave_status() will skip the
second part of enumeration because the slave->status has not changed.

This scenario can happen because PINGs are handled in a workqueue
function which is working from a snapshot of an old PING, and there
is no guarantee when this function will run.

A peripheral could report attached in the PING being handled by
sdw_handle_slave_status(), but has since reverted to device #0 and is
then found in the loop in sdw_program_device_num(). Previously the
code would not have updated slave->status to UNATTACHED because it had
not yet handled a PING where that peripheral had UNATTACHED.

This situation happens fairly frequently with multiple peripherals on
a bus that are intentionally reset (for example after downloading
firmware).
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20220914160248.1047627-4-rf@opensource.cirrus.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Ensure that if sdw_handle_slave_status() sees a peripheral
has dropped off the bus it reports it to the client driver.

If there are any devices reporting on address 0 it bails out
after programming the device IDs. So it never reaches the second
loop that calls sdw_update_slave_status().

If the missing device is one that is now showing as unenumerated
it has been given a device ID so will report as attached next
time sdw_handle_slave_status() runs.

With the previous code the client driver would only see another
ATTACHED notification because the UNATTACHED state was lost when
sdw_handle_slave_status() bailed out after programming the
device ID.

This shows up most when the peripheral has to be reset after
downloading updated firmware and there are multiple of these
peripherals on the bus. They will all return to unenumerated state
after the reset, and then there is a mix of unattached, attached
and unenumerated PING states from the peripherals, as each is reset
and they reboot.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20220914160248.1047627-3-rf@opensource.cirrus.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

The cadence IP explicitly reports slave status changes with bits for
each possible change. The function cdns_update_slave_status() attempts
to translate this into the current status of each of the slaves.

However when there are multiple peripherals on a bus any slave that did
not have a status change when the work function ran would not have it's
status updated - the array is initialised to a value that equates to
UNATTACHED and this can cause spurious reports that slaves had dropped
off the bus.

In the case where a slave has no status change or has multiple status
changes the value from the last PING command is used.
Signed-off-by: Simon Trimmer <simont@opensource.cirrus.com>
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20220914160248.1047627-2-rf@opensource.cirrus.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Regroup offset and bitfield definitions.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823053846.2684635-12-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Regroup offset and bitfield definitions
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823053846.2684635-11-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Regroup offset and bitfield definitions.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823053846.2684635-10-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Regroup offset and bitfield definitions.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823053846.2684635-9-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Regroup offset and bitfields
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823053846.2684635-8-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

add comment and newline to mark out control stream capabilities and
chmap. These registers are unused by the driver, only dumped in
debugfs.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823053846.2684635-7-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

We removed PDM support a long time ago but kept the definitions.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823053846.2684635-6-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Regroup offset and bitfields, no functionality change
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823053846.2684635-5-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

This read-only register only defines an offset which is known already
and a version which isn't used.

Remove unused definition.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823053846.2684635-4-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

No functionality change, just regroup offset and bitfield definitions.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823053846.2684635-3-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Add definition in header file rather than hidden in code.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823053846.2684635-2-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

The allowed values for SoundWire device numbers are between 1 and 11
(inclusive). HDaudio/iDISP codecs typically use SDI values 0..3
(inclusive). To allow for a unique peripheral SDI/dev_number across
HDaudio and SoundWire buses, we set the minimum base to 4. This still
allows for 8 SoundWire peripherals in the system, currently more than
needed in actual products.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823045004.2670658-4-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

The SoundWire specification allows the device number to be allocated
at will. When a system includes multiple SoundWire links, the device
number scope is limited to the link to which the device is attached.

However, for integration/debug it can be convenient to have a unique
device number across the system. This patch adds a 'dev_num_ida_min'
field at the bus level, which when set will be used to allocate an
IDA.

The allocation happens when a hardware device reports as ATTACHED. If
any error happens during the enumeration, the allocated IDA is not
freed - the device number will be reused if/when the device re-joins
the bus. The IDA is only freed when the Linux device is unregistered.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823045004.2670658-3-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

To avoid confusions with follow-up patches using a IDA mechanism for
peripheral 'device number' allocation, rename sdw_ida as sdw_bus_ida.

Pure rename, no functionality change.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823045004.2670658-2-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

The module and function information can be added with
'modprobe foo dyndbg=+pmf'
Suggested-by: Greg KH <gregkh@linuxfoundation.org>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823050158.2671245-3-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

The module and function information can be added with
'modprobe foo dyndbg=+pmf'
Suggested-by: Greg KH <gregkh@linuxfoundation.org>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823050158.2671245-2-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

The DSDT for this device has a number of problems:
a) it lists rt711 on link0 and link1, but link1 is disabled
b) the rt711 entry on link0 uses the wrong v2 instead of v3 (SDCA)
c) the rt1316 amplifier on link3 is not listed.

Add a remapping table to work-around these BIOS shenanigans.

BugLink: https://github.com/thesofproject/sof/issues/5955Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220823030919.2346629-1-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

The capabilities enabled for multi-link are required as part of the
programming sequences, even when a stream uses a single link we still
use the syncArm/syncGo sequences. Therefore the TODO is no longer
necessary.
Suggested-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Khalid Masum <khalid.masum.92@gmail.com>
Link: https://lore.kernel.org/r/20220817074859.4759-1-khalid.masum.92@gmail.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Update error prints to debug prints to avoid redundant logging in kernel
boot time, as these prints are informative prints in irq handler.
Signed-off-by: Srinivasa Rao Mandadapu <quic_srivasam@quicinc.com>
Reviewed-by: Andrew Halaney <ahalaney@redhat.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/1657724067-19004-1-git-send-email-quic_srivasam@quicinc.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Radix tree header includes gfp.h for __GFP_BITS_SHIFT only. Now we
have gfp_types.h for this.

Fixes powerpc allmodconfig build:

   In file included from include/linux/nodemask.h:97,
                    from include/linux/mmzone.h:17,
                    from include/linux/gfp.h:7,
                    from include/linux/radix-tree.h:12,
                    from include/linux/idr.h:15,
                    from include/linux/kernfs.h:12,
                    from include/linux/sysfs.h:16,
                    from include/linux/kobject.h:20,
                    from include/linux/pci.h:35,
                    from arch/powerpc/kernel/prom_init.c:24:
   include/linux/random.h: In function 'add_latent_entropy':
>> include/linux/random.h:25:46: error: 'latent_entropy' undeclared (first use in this function); did you mean 'add_latent_entropy'?
      25 |         add_device_randomness((const void *)&latent_entropy, sizeof(latent_entropy));
         |                                              ^~~~~~~~~~~~~~
         |                                              add_latent_entropy
   include/linux/random.h:25:46: note: each undeclared identifier is reported only once for each function it appears in
Reported-by: kernel test robot <lkp@intel.com>
CC: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull vfs lseek fix from Al Viro:
 "Fix proc_reg_llseek() breakage. Always had been possible if somebody
  left NULL ->proc_lseek, became a practical issue now"

* tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  take care to handle NULL ->proc_lseek()

Easily done now, just by clearing FMODE_LSEEK in ->f_mode
during proc_reg_open() for such entries.

Fixes: 868941b1 "fs: remove no_llseek"
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>