Commit Graph

70 Commits

Author SHA1 Message Date
Linus Torvalds 4feaab05dc LED updates for 5.4-rc1
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Merge tag 'leds-for-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds

Pull LED updates from Jacek Anaszewski:
 "In this cycle we've finally managed to contribute the patch set
  sorting out LED naming issues. Besides that there are many changes
  scattered among various LED class drivers and triggers.

  LED naming related improvements:

   - add new 'function' and 'color' fwnode properties and deprecate
     'label' property which has been frequently abused for conveying
     vendor specific names that have been available in sysfs anyway

   - introduce a set of standard LED_FUNCTION* definitions

   - introduce a set of standard LED_COLOR_ID* definitions

   - add a new {devm_}led_classdev_register_ext() API with the
     capability of automatic LED name composition basing on the
     properties available in the passed fwnode; the function is
     backwards compatible in a sense that it uses 'label' data, if
     present in the fwnode, for creating LED name

   - add tools/leds/get_led_device_info.sh script for retrieving LED
     vendor, product and bus names, if applicable; it also performs
     basic validation of an LED name

   - update following drivers and their DT bindings to use the new LED
     registration API:

        - leds-an30259a, leds-gpio, leds-as3645a, leds-aat1290, leds-cr0014114,
          leds-lm3601x, leds-lm3692x, leds-lp8860, leds-lt3593, leds-sc27xx-blt

  Other LED class improvements:

   - replace {devm_}led_classdev_register() macros with inlines

   - allow to call led_classdev_unregister() unconditionally

   - switch to use fwnode instead of be stuck with OF one

  LED triggers improvements:

   - led-triggers:
        - fix dereferencing of null pointer
        - fix a memory leak bug

   - ledtrig-gpio:
        - GPIO 0 is valid

  Drop superseeded apu2/3 support from leds-apu since for apu2+ a newer,
  more complete driver exists, based on a generic driver for the AMD
  SOCs gpio-controller, supporting LEDs as well other devices:

   - drop profile field from priv data

   - drop iosize field from priv data

   - drop enum_apu_led_platform_types

   - drop superseeded apu2/3 led support

   - add pr_fmt prefix for better log output

   - fix error message on probing failure

  Other misc fixes and improvements to existing LED class drivers:

   - leds-ns2, leds-max77650:
        - add of_node_put() before return

   - leds-pwm, leds-is31fl32xx:
        - use struct_size() helper

   - leds-lm3697, leds-lm36274, leds-lm3532:
        - switch to use fwnode_property_count_uXX()

   - leds-lm3532:
        - fix brightness control for i2c mode
        - change the define for the fs current register
        - fixes for the driver for stability
        - add full scale current configuration
        - dt: Add property for full scale current.
        - avoid potentially unpaired regulator calls
        - move static keyword to the front of declarations
        - fix optional led-max-microamp prop error handling

   - leds-max77650:
        - add of_node_put() before return
        - add MODULE_ALIAS()
        - Switch to fwnode property API

   - leds-as3645a:
        - fix misuse of strlcpy

   - leds-netxbig:
        - add of_node_put() in netxbig_leds_get_of_pdata()
        - remove legacy board-file support

   - leds-is31fl319x:
        - simplify getting the adapter of a client

   - leds-ti-lmu-common:
        - fix coccinelle issue
        - move static keyword to the front of declaration

   - leds-syscon:
        - use resource managed variant of device register

   - leds-ktd2692:
        - fix a typo in the name of a constant

   - leds-lp5562:
        - allow firmware files up to the maximum length

   - leds-an30259a:
        - fix typo

   - leds-pca953x:
        - include the right header"

* tag 'leds-for-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds: (72 commits)
  leds: lm3532: Fix optional led-max-microamp prop error handling
  led: triggers: Fix dereferencing of null pointer
  leds: ti-lmu-common: Move static keyword to the front of declaration
  leds: lm3532: Move static keyword to the front of declarations
  leds: trigger: gpio: GPIO 0 is valid
  leds: pwm: Use struct_size() helper
  leds: is31fl32xx: Use struct_size() helper
  leds: ti-lmu-common: Fix coccinelle issue in TI LMU
  leds: lm3532: Avoid potentially unpaired regulator calls
  leds: syscon: Use resource managed variant of device register
  leds: Replace {devm_}led_classdev_register() macros with inlines
  leds: Allow to call led_classdev_unregister() unconditionally
  leds: lm3532: Add full scale current configuration
  dt: lm3532: Add property for full scale current.
  leds: lm3532: Fixes for the driver for stability
  leds: lm3532: Change the define for the fs current register
  leds: lm3532: Fix brightness control for i2c mode
  leds: Switch to use fwnode instead of be stuck with OF one
  leds: max77650: Switch to fwnode property API
  led: triggers: Fix a memory leak bug
  ...
2019-09-17 18:40:42 -07:00
Ding Xiang 961b6ffe0e stm class: Fix a double free of stm_source_device
In the error path of stm_source_register_device(), the kfree is
unnecessary, as the put_device() before it ends up calling
stm_source_device_release() to free stm_source_device, leading to
a double free at the outer kfree() call. Remove it.

Signed-off-by: Ding Xiang <dingxiang@cmss.chinamobile.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Fixes: 7bd1d4093c ("stm class: Introduce an abstraction for System Trace Module devices")
Link: https://lore.kernel.org/linux-arm-kernel/1563354988-23826-1-git-send-email-dingxiang@cmss.chinamobile.com/
Cc: stable@vger.kernel.org # v4.4+
Link: https://lore.kernel.org/r/20190821074955.3925-2-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-28 22:29:01 +02:00
Suzuki K Poulose 6cda08a20d drivers: Introduce device lookup variants by name
Add a helper to match the device name for device lookup. Also
reuse this generic exported helper for the existing bus_find_device_by_name().
and add similar variants for driver/class.

Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexander Aring <alex.aring@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Murphy <dmurphy@ti.com>
Cc: Harald Freudenberger <freude@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: linux-leds@vger.kernel.org
Cc: linux-rtc@vger.kernel.org
Cc: linux-usb@vger.kernel.org
Cc: linux-wpan@vger.kernel.org
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Stefan Schmidt <stefan@datenfreihafen.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20190723221838.12024-2-suzuki.poulose@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-30 13:07:41 +02:00
Thomas Gleixner ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Alexander Shishkin 51e0f22781 stm class: Fix channel bitmap on 32-bit systems
Commit 7bd1d4093c ("stm class: Introduce an abstraction for System Trace
Module devices") naively calculates the channel bitmap size in 64-bit
chunks regardless of the size of underlying unsigned long, making the
bitmap half as big on a 32-bit system. This leads to an out of bounds
access with the upper half of the bitmap.

Fix this by using BITS_TO_LONGS. While at it, convert to using
struct_size() for the total size calculation of the master struct.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Fixes: 7bd1d4093c ("stm class: Introduce an abstraction for System Trace Module devices")
Reported-by: Mulu He <muluhe@codeaurora.org>
Cc: stable@vger.kernel.org # v4.4+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25 11:31:17 +02:00
Tingwei Zhang ee496da4c3 stm class: Fix channel free in stm output free path
Number of free masters is not set correctly in stm
free path. Fix this by properly adding the number
of output channels before setting them to 0 in
stm_output_disclaim().

Currently it is equivalent to doing nothing since
master->nr_free is incremented by 0.

Fixes: 7bd1d4093c ("stm class: Introduce an abstraction for System Trace Module devices")
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Cc: stable@vger.kernel.org # v4.4
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25 11:31:17 +02:00
Alexander Shishkin bf7cbaae08 stm class: Prevent division by zero
Using STP_POLICY_ID_SET ioctl command with dummy_stm device, or any STM
device that supplies zero mmio channel size, will trigger a division by
zero bug in the kernel.

Prevent this by disallowing channel widths other than 1 for such devices.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Fixes: 7bd1d4093c ("stm class: Introduce an abstraction for System Trace Module devices")
CC: stable@vger.kernel.org # v4.4+
2019-02-21 17:44:18 +02:00
Zhi Jin a1d75dad3a stm class: Fix an endless loop in channel allocation
There is a bug in the channel allocation logic that leads to an endless
loop when looking for a contiguous range of channels in a range with a
mixture of free and occupied channels. For example, opening three
consequtive channels, closing the first two and requesting 4 channels in
a row will trigger this soft lockup. The bug is that the search loop
forgets to skip over the range once it detects that one channel in that
range is occupied.

Restore the original intent to the logic by fixing the omission.

Signed-off-by: Zhi Jin <zhi.jin@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Fixes: 7bd1d4093c ("stm class: Introduce an abstraction for System Trace Module devices")
CC: stable@vger.kernel.org # v4.4+
2019-02-21 17:44:18 +02:00
Alexander Shishkin c18614a1a1 stm class: Fix a module refcount leak in policy creation error path
Commit c7fd62bc69 ("stm class: Introduce framing protocol drivers")
adds a bug into the error path of policy creation, that would do a
module_put() on a wrong module, if one tried to create a policy for
an stm device which already has a policy, using a different protocol.
IOW,

| mkdir /config/stp-policy/dummy_stm.0:p_basic.test
| mkdir /config/stp-policy/dummy_stm.0:p_sys-t.test # puts "p_basic"
| mkdir /config/stp-policy/dummy_stm.0:p_sys-t.test # "p_basic" -> -1

throws:

| general protection fault: 0000 [#1] SMP PTI
| CPU: 3 PID: 2887 Comm: mkdir
| RIP: 0010:module_put.part.31+0xe/0x90
| Call Trace:
|  module_put+0x13/0x20
|  stm_put_protocol+0x11/0x20 [stm_core]
|  stp_policy_make+0xf1/0x210 [stm_core]
|  ? __kmalloc+0x183/0x220
|  ? configfs_mkdir+0x10d/0x4c0
|  configfs_mkdir+0x169/0x4c0
|  vfs_mkdir+0x108/0x1c0
|  do_mkdirat+0xe8/0x110
|  __x64_sys_mkdir+0x1b/0x20
|  do_syscall_64+0x5a/0x140
|  entry_SYSCALL_64_after_hwframe+0x44/0xa9

Correct this sad mistake by calling calling 'put' on the correct
reference, which happens to match another error path in the same
function, so we consolidate the two at the same time.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Fixes: c7fd62bc69 ("stm class: Introduce framing protocol drivers")
Reported-by: Ammy Yi <ammy.yi@intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-19 20:21:06 +01:00
Alexander Shishkin a23bbec205 stm class: Use memcat_p()
Instead of a local copy, use the memcat_p() helper to merge policy
node attributes.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11 12:12:55 +02:00
Alexander Shishkin 6c7e4b6882 stm class: heartbeat: Fix whitespace
Fix whitespace in the code for better readability, no functional changes.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11 12:12:55 +02:00
Alexander Shishkin 39f10239df stm class: p_sys-t: Add support for CLOCKSYNC packets
This adds support for CLOCKSYNC SyS-T packets, that establish correlation
between the transport clock (STP timestamps) and SyS-T timestamps. These
packets are sent periodically to allow the decoder to keep both time
sources in sync.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11 12:12:54 +02:00
Alexander Shishkin d69d5e8311 stm class: Add MIPI SyS-T protocol support
This adds support for MIPI SyS-T protocol as specified in an open
standard [1]. In addition to marking message boundaries, it also
supports tagging messages with the source UUID, to provide better
distinction between trace sources, including payload length and
timestamp in the message's metadata.

This driver adds attributes to STP policy nodes to control/configure
these metadata features.

[1] https://www.mipi.org/specifications/sys-t

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11 12:12:54 +02:00
Alexander Shishkin 24c7bcb6a7 stm class: Switch over to the protocol driver
Now that the default framing protocol is factored out into its own driver,
switch over to using the driver for writing data. To that end, make the
policy code require a valid protocol name (or absence thereof, which is
equivalent to "p_basic").

Also, to make transition easier, make stm class request "p_basic" module
at initialization time.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11 12:12:54 +02:00
Alexander Shishkin a02509f301 stm class: Factor out default framing protocol
The STP framing pattern that the stm class implicitly applies to the
data payload is, in fact, a protocol. This patch moves the relevant code
out of the stm core into its own driver module.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11 12:12:54 +02:00
Alexander Shishkin d279a38020 stm class: Add a helper for writing data packets
Add a helper to write a sequence of bytes as STP data packets. This
is used by protocol drivers to output their metadata, as well as the
actual data payload.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11 12:12:54 +02:00
Alexander Shishkin c7fd62bc69 stm class: Introduce framing protocol drivers
At the moment, the stm class applies a certain STP framing pattern to
the data as it is written to the underlying STM device. In order to
allow different framing patterns (aka protocols), this patch introduces
the concept of STP protocol drivers, defines data structures and APIs
for the protocol drivers to use.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11 12:12:54 +02:00
Alexander Shishkin e967b8bdd4 stm class: Clean up stp_configfs_init
Minor code shortening, no functional changes.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11 12:12:54 +02:00
Alexander Shishkin 25e3c0062a stm class: Clarify configfs root type/operations names
The current naming of stp-policy root type and group ops is confusing,
rename them for better readability.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11 12:12:54 +02:00
Alexander Shishkin cb6102bd99 stm class: Rework policy node fallback
Currently, if no matching policy node can be found for a trace source,
we'll try to use "default" policy node, then, if that doesn't exist,
we'll pick the first node, in order of creation. If that also fails,
we'll allocate M/C range from the beginning of the device's M/C range.

This makes it difficult to know which node (if any) was used in any
particular case.

In order to make things more deterministic, the new order is as follows:
  * if they supply ID string, use that and nothing else,
  * if they are a task, use their task name (comm),
  * use "default", if it exists,
  * return failure, to let them know there is no suitable rule.

This should provide enough convenience with the "default" catch-all node,
while not leaving *everything* to chance. As a side effect, this relaxes
the requirement of using ioctl() for identification with the possibility of
using task names as policy nodes.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-11 12:12:54 +02:00
Linus Torvalds abf7dba7c4 Char/Misc driver patches for 4.18-rc1
Here is the "big" char and misc driver patches for 4.18-rc1.
 
 It's not a lot of stuff here, but there are some highlights:
 	- coreboot driver updates
 	- soundwire driver updates
 	- android binder updates
 	- fpga big sync, mostly documentation
 	- lots of minor driver updates
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the "big" char and misc driver patches for 4.18-rc1.

  It's not a lot of stuff here, but there are some highlights:

   - coreboot driver updates

   - soundwire driver updates

   - android binder updates

   - fpga big sync, mostly documentation

   - lots of minor driver updates

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (81 commits)
  vmw_balloon: fixing double free when batching mode is off
  MAINTAINERS: Add driver-api/fpga path
  fpga: clarify that unregister functions also free
  documentation: fpga: move fpga-region.txt to driver-api
  documentation: fpga: add bridge document to driver-api
  documentation: fpga: move fpga-mgr.txt to driver-api
  Documentation: fpga: move fpga overview to driver-api
  fpga: region: kernel-doc fixes
  fpga: bridge: kernel-doc fixes
  fpga: mgr: kernel-doc fixes
  fpga: use SPDX
  fpga: region: change api, add fpga_region_create/free
  fpga: bridge: change api, don't use drvdata
  fpga: manager: change api, don't use drvdata
  fpga: region: don't use drvdata in common fpga code
  Drivers: hv: vmbus: Removed an unnecessary cast from void *
  ver_linux: Drop redundant calls to system() to test if file is readable
  ver_linux: Move stderr redirection from function parameter to function body
  misc: IBM Virtual Management Channel Driver (VMC)
  rpmsg: Correct support for MODULE_DEVICE_TABLE()
  ...
2018-06-05 16:20:22 -07:00
Greg Kroah-Hartman 806e30873f hwtracing: stm: fix build error on some arches
Commit b5e2ced9bf ("stm class: Use vmalloc for the master map") caused
a build error on some arches as vmalloc.h was not explicitly included.

Fix that by adding it to the list of includes.

Fixes: b5e2ced9bf ("stm class: Use vmalloc for the master map")
Reported-by: kbuild test robot <lkp@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-26 08:49:24 +02:00
Alexander Shishkin b5e2ced9bf stm class: Use vmalloc for the master map
Fengguang is running into a warning from the buddy allocator:

> swapper/0: page allocation failure: order:9, mode:0x14040c0(GFP_KERNEL|__GFP_COMP), nodemask=(null)
> CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.17.0-rc1 #262
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
> Call Trace:
...
>  __kmalloc+0x14b/0x180: ____cache_alloc at mm/slab.c:3127
>  stm_register_device+0xf3/0x5c0: stm_register_device at drivers/hwtracing/stm/core.c:695
...

Which is basically a result of the stm class trying to allocate ~512kB
for the dummy_stm with its default parameters. There's no reason, however,
for it not to be vmalloc()ed instead, which is what this patch does.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
CC: stable@vger.kernel.org # v4.4+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 18:09:16 +02:00
Mathieu Poirier ad0dfdfd87 coresight: Moving framework and drivers to SPDX identifier
Moving all kernel side CoreSight framework and drivers to SPDX identifier.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14 16:19:59 +02:00
Alexander Shishkin 4f0c7c6a12 stm class: Make dummy's master/channel ranges configurable
To allow for more flexible testing of the stm class, make it possible
to specify the ranges of masters and channels that the dummy_stm devices
cover. This is done via module parameters.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
2018-03-28 18:47:18 +03:00
Alexander Shishkin 9ea393d8d8 stm class: Add SPDX GPL-2.0 header to replace GPLv2 boilerplate
This adds SPDX GPL-2.0 header to to stm core files and removes the
GPLv2 boilerplate text.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
2018-03-28 18:47:17 +03:00
Felipe Balbi a773d41927 tracing: Pass export pointer as argument to ->write()
By passing an export descriptor to the write function, users don't need to
keep a global static pointer and can rely on container_of() to fetch their
own structure.

Link: http://lkml.kernel.org/r/20170602102025.5140-1-felipe.balbi@linux.intel.com

Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-04 07:14:30 -05:00
Linus Torvalds abc36be236 A couple of configfs cleanups:
- proper use of the bool type (Thomas Meyer)
   - constification of struct config_item_type (Bhumika Goyal)
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Merge tag 'configfs-for-4.15' of git://git.infradead.org/users/hch/configfs

Pull configfs updates from Christoph Hellwig:
 "A couple of configfs cleanups:

   - proper use of the bool type (Thomas Meyer)

   - constification of struct config_item_type (Bhumika Goyal)"

* tag 'configfs-for-4.15' of git://git.infradead.org/users/hch/configfs:
  RDMA/cma: make config_item_type const
  stm class: make config_item_type const
  ACPI: configfs: make config_item_type const
  nvmet: make config_item_type const
  usb: gadget: configfs: make config_item_type const
  PCI: endpoint: make config_item_type const
  iio: make function argument and some structures const
  usb: gadget: make config_item_type structures const
  dlm: make config_item_type const
  netconsole: make config_item_type const
  nullb: make config_item_type const
  ocfs2/cluster: make config_item_type const
  target: make config_item_type const
  configfs: make ci_type field, some pointers and function arguments const
  configfs: make config_item_type const
  configfs: Fix bool initialization/comparison
2017-11-14 14:44:04 -08:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Bhumika Goyal 085006e834 stm class: make config_item_type const
Make config_item_type structures const as they are either passed to a
function having the argument as const or used inside a if statement or
stored in the const "ci_type" field of a config_item structure.

Done using Coccinelle.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-10-19 16:15:30 +02:00
Alexander Shishkin fd085bb176 stm class: Fix a use-after-free
For reasons unknown, the stm_source removal path uses device_destroy()
to kill the underlying device object. Because device_destroy() uses
devt to look for the device to destroy and the fact that stm_source
devices don't have one (or all have the same one), it just picks the
first device in the class, which may well be the wrong one.

That is, loading stm_console and stm_heartbeat and then removing both
will die in dereferencing a freed object.

Since this should have been device_unregister() in the first place,
use it instead of device_destroy().

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Fixes: 7bd1d4093c ("stm class: Introduce an abstraction for System Trace Module devices")
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-22 10:28:00 +02:00
Dan Carpenter 71c488f32b stm: Potential read overflow in stm_char_policy_set_ioctl()
The "size" variable comes from the user so we need to verify that it's
large enough to hold an stp_policy_id struct.

Fixes: 7bd1d4093c ("stm class: Introduce an abstraction for System Trace Module devices")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
2017-08-25 17:58:33 +03:00
Linus Torvalds 179a7ba680 This release has a few updates:
o STM can hook into the function tracer
  o Function filtering now supports more advance glob matching
  o Ftrace selftests updates and added tests
  o Softirq tag in traces now show only softirqs
  o ARM nop added to non traced locations at compile time
  o New trace_marker_raw file that allows for binary input
  o Optimizations to the ring buffer
  o Removal of kmap in trace_marker
  o Wakeup and irqsoff tracers now adhere to the set_graph_notrace file
  o Other various fixes and clean ups
 
 Note, there are two patches marked for stable. These were discovered
 near the end of the 4.9 rc release cycle. By the time I had them tested
 it was just a matter of days before 4.9 would be released, and I
 figured I would just submit them in the merge window. They are old
 bugs and not critical. Nothing non-root could abuse.
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Merge tag 'trace-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "This release has a few updates:

   - STM can hook into the function tracer
   - Function filtering now supports more advance glob matching
   - Ftrace selftests updates and added tests
   - Softirq tag in traces now show only softirqs
   - ARM nop added to non traced locations at compile time
   - New trace_marker_raw file that allows for binary input
   - Optimizations to the ring buffer
   - Removal of kmap in trace_marker
   - Wakeup and irqsoff tracers now adhere to the set_graph_notrace file
   - Other various fixes and clean ups"

* tag 'trace-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (42 commits)
  selftests: ftrace: Shift down default message verbosity
  kprobes/trace: Fix kprobe selftest for newer gcc
  tracing/kprobes: Add a helper method to return number of probe hits
  tracing/rb: Init the CPU mask on allocation
  tracing: Use SOFTIRQ_OFFSET for softirq dectection for more accurate results
  tracing/fgraph: Have wakeup and irqsoff tracers ignore graph functions too
  fgraph: Handle a case where a tracer ignores set_graph_notrace
  tracing: Replace kmap with copy_from_user() in trace_marker writing
  ftrace/x86_32: Set ftrace_stub to weak to prevent gcc from using short jumps to it
  tracing: Allow benchmark to be enabled at early_initcall()
  tracing: Have system enable return error if one of the events fail
  tracing: Do not start benchmark on boot up
  tracing: Have the reg function allow to fail
  ring-buffer: Force rb_end_commit() and rb_set_commit_to_write() inline
  ring-buffer: Froce rb_update_write_stamp() to be inlined
  ring-buffer: Force inline of hotpath helper functions
  tracing: Make __buffer_unlock_commit() always_inline
  tracing: Make tracepoint_printk a static_key
  ring-buffer: Always inline rb_event_data()
  ring-buffer: Make rb_reserve_next_event() always inlined
  ...
2016-12-15 13:49:34 -08:00
Chunyan Zhang 9dfed80d87 stm: Mark the functions of writing STM with notrace
If CONFIG_STM_SOURCE_FTRACE is selected, Function trace data can be
writen to sink via STM, all functions that related to writing data
packets to STM should be marked 'notrace' to avoid being traced by
Ftrace, otherwise the program would stall into an endless loop.

Link: http://lkml.kernel.org/r/1479715043-6534-7-git-send-email-zhang.chunyan@linaro.org

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-22 17:48:04 -05:00
Chunyan Zhang 9b5e3ff6b9 stm dummy: Mark dummy_stm_packet() with notrace
If CONFIG_STM_SOURCE_FTRACE is selected, Function trace data can be
writen to sink via STM, all functions that related to writing data
packets to STM should be marked 'notrace' to avoid being traced by
Ftrace, otherwise the program would stall into an endless loop.

Link: http://lkml.kernel.org/r/1479715043-6534-6-git-send-email-zhang.chunyan@linaro.org

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-22 17:48:00 -05:00
Chunyan Zhang 262e1f6e39 stm class: ftrace: Add ftrace-export-over-stm driver
This patch adds a driver that models itself as an stm_source called
stm_ftrace. Once the stm device and stm_ftrace have been linked via
sysfs, the driver registers itself as a trace_export and everything
passed to the interface from Ftrace subsystem will end up in the STM
trace engine.

Link: http://lkml.kernel.org/r/1479715043-6534-3-git-send-email-zhang.chunyan@linaro.org

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-22 17:47:48 -05:00
Johan Hovold a0ebf519b8 stm class: Fix device leak in open error path
Make sure to drop the reference taken by class_find_device() also on
allocation errors in open().

Signed-off-by: Johan Hovold <johan@kernel.org>
Fixes: 7bd1d4093c ("stm class: Introduce an abstraction for...")
Cc: stable@vger.kernel.org # v4.6+
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
2016-11-18 16:54:39 +02:00
Alexander Shishkin 8e0469a4f3 stm class: Add runtime power management handling
Currently, there's no runtime pm in stm class devices, which makes it
harder for the underlying hardware drivers to handle their power
management.

This patch applies the following runtime pm policy to stm class devices,
which their parents can rely on for their power management tracking:

  * device is in use during character device writes,
  * delayed autosuspend is used to keep it active between adjacent
  writes,
  * device is in use while mmio regions are mapped,
  * device is is use while any stm_source devices are linked to it.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Chunyan Zhang <zhang.chunyan@linaro.org>
2016-07-01 11:00:14 +03:00
Alexander Shishkin 8e996a2874 stm class: Support devices that override software assigned masters
Some STM devices adjust software assigned master numbers depending on
the trace source and its runtime state and whatnot. This patch adds
a sysfs attribute to inform the trace-side software that master numbers
assigned to software sources will not match those in the STP stream,
so that, for example, master/channel allocation policy can be adjusted
accordingly.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-03 14:59:30 -07:00
Alexander Shishkin fb0801904b stm class: Remove unnecessary pointer increment
Readability: a postfix increment is used on a pointer which is not
used anywhere afterwards, which may send the reader looking through
the function one extra time. Drop the unnecessary increment.

Reported-by: Alan Cox <alan.cox@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Laurent Fert <laurent.fert@intel.com>
2016-04-08 16:11:54 +03:00
Alexander Shishkin 389b6699a2 stm class: Fix stm device initialization order
Currently, stm_register_device() makes the device visible and then
proceeds to initializing spinlocks and other properties, which leaves
a window when the device can already be opened but is not yet fully
operational.

Fix this by reversing the initialization order.

Reported-by: Alan Cox <alan.cox@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Laurent Fert <laurent.fert@intel.com>
2016-04-08 16:11:53 +03:00
Alexander Shishkin cbe4a61d1d stm class: Do not leak the chrdev in error path
Currently, the error path of stm_register_device() forgets to unregister
the chrdev. Fix this.

Reported-by: Alan Cox <alan.cox@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Laurent Fert <laurent.fert@intel.com>
2016-04-08 16:11:52 +03:00
Alexander Shishkin 8fa11d1c13 stm class: Remove a pointless line
No point in explicitly setting something to zero right after we
explicitly checked that it is zero. Fix this.

Reported-by: Alan Cox <alan.cox@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Laurent Fert <laurent.fert@intel.com>
2016-04-08 16:11:52 +03:00
Alexander Shishkin c8be489944 stm class: stm_heartbeat: Make nr_devs parameter read-only
Changing nr_devs after the module has been loaded doesn't actually
change anything, so just make it read-only.

Reported-by: Alan Cox <alan.cox@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Laurent Fert <laurent.fert@intel.com>
2016-04-08 16:11:51 +03:00
Alexander Shishkin 118b4515aa stm class: dummy_stm: Make nr_dummies parameter read-only
Changing nr_dummies after the module has been loaded doesn't actually
change anything, so just make it read-only.

Reported-by: Alan Cox <alan.cox@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Laurent Fert <laurent.fert@intel.com>
2016-04-08 16:11:50 +03:00
Chunyan Zhang f57af6df6a stm class: Fix integer boundary checks for master range
Master IDs are of unsigned int type, yet in the configfs policy code
we're validating user's input against INT_MAX. This is both pointless
and misleading as the real limits are imposed by the stm device's
[sw_start..sw_end] (which are also limited by the spec to be no larger
than 2^16-1).

Clean this up by getting rid of the redundant comparisons.

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Laurent Fert <laurent.fert@intel.com>
2016-04-08 16:08:00 +03:00
Alexander Shishkin adcde635f5 stm class: dummy_stm: Add link callback for fault injection
STM device's link callback has the power to abort master/channel
assignment by returning a negative error code. Use this in dummy
stm device to optionally abort assigning certain channel IDs.
This is useful as fault injection into the stm class core, for
testing purposes.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20 14:09:14 -08:00
Alexander Shishkin cc8424074e stm class: Plug stm device's unlink callback
STM device's unlink callback is never actually called from anywhere in
the stm class code.

This patch adds calls to stm driver's unlink method after the unlinking
has succeeded.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20 14:09:14 -08:00
Alexander Shishkin b4ca34aaf7 stm class: Fix a race in unlinking
There is a window in stm_source_link_drop(), during which the source's
link may change before locks are acquired. When this happens, it throws
a warning, since this is not an expected scenario.

This patch handles the race in such a way that if the link appears to
have changed by the time we took the locks, it will release them and
repeat the whole unlinking procedure from the beginning, unless the
other contender beat us to it.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20 14:09:14 -08:00
Alexander Shishkin f7c81c7176 stm class: Fix unbalanced module/device refcounting
STM code takes references to the stm device and its module for the
duration of the character device's existence or the stm_source link.
Dropping these references is not well balanced everywhere, which may
lead to leaks.

This patch balances the acquisition and releasing of these two
references and annotates each site so that it's easier to verify
correctness by reading the code.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20 14:09:14 -08:00