[ Upstream commit 07d2390e36ee5b3265e9cc8305f2a106c8721e16 ]

In certain probe conditions the interrupt came right after registering
the handler causing a NULL pointer exception because of uninitialized
waitqueue:

$ udevadm trigger
i2c-gpio i2c-gpio-1: using pins 143 (SDA) and 144 (SCL)
i2c-gpio i2c-gpio-3: using pins 53 (SDA) and 52 (SCL)
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = e8b38000
[00000000] *pgd=00000000
Internal error: Oops: 5 [#1] SMP ARM
Modules linked in: snd_soc_i2s(+) i2c_gpio(+) snd_soc_idma snd_soc_s3c_dma snd_soc_core snd_pcm_dmaengine snd_pcm snd_timer snd soundcore ac97_bus spi_s3c64xx pwm_samsung dwc2 exynos_adc phy_exynos_usb2 exynosdrm exynos_rng rng_core rtc_s3c
CPU: 0 PID: 717 Comm: data-provider-m Not tainted 4.6.0-rc1-next-20160401-00011-g1b8d87473b9e-dirty #101
Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
(...)
(__wake_up_common) from [<c0379624>] (__wake_up+0x38/0x4c)
(__wake_up) from [<c0a41d30>] (ak8975_irq_handler+0x28/0x30)
(ak8975_irq_handler) from [<c0386720>] (handle_irq_event_percpu+0x88/0x140)
(handle_irq_event_percpu) from [<c038681c>] (handle_irq_event+0x44/0x68)
(handle_irq_event) from [<c0389c40>] (handle_edge_irq+0xf0/0x19c)
(handle_edge_irq) from [<c0385e04>] (generic_handle_irq+0x24/0x34)
(generic_handle_irq) from [<c05ee360>] (exynos_eint_gpio_irq+0x50/0x68)
(exynos_eint_gpio_irq) from [<c0386720>] (handle_irq_event_percpu+0x88/0x140)
(handle_irq_event_percpu) from [<c038681c>] (handle_irq_event+0x44/0x68)
(handle_irq_event) from [<c0389a70>] (handle_fasteoi_irq+0xb4/0x194)
(handle_fasteoi_irq) from [<c0385e04>] (generic_handle_irq+0x24/0x34)
(generic_handle_irq) from [<c03860b4>] (__handle_domain_irq+0x5c/0xb4)
(__handle_domain_irq) from [<c0301774>] (gic_handle_irq+0x54/0x94)
(gic_handle_irq) from [<c030c910>] (__irq_usr+0x50/0x80)

The bug was reproduced on exynos4412-trats2 (with a max77693 device also
using i2c-gpio) after building max77693 as a module.

Cc: <stable@vger.kernel.org>
Fixes: 94a6d5cf7caa ("iio:ak8975 Implement data ready interrupt handling")
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Tested-by: Gregor Boirie <gregor.boirie@parrot.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

Jonathan writes:

The usual mixed bag of fixes for IIO in the 4.1 cycle.

Second version of this pull request as a small fix to a fix turned
up before Greg pulled it for a cc10001 patch near the top of the tree.

One core fix

* Set updated for a iio kfifo was incorrectly set to false during a failed
  update, resulting in atttempts to repeat the failed operation appearing
  to succeed.

This time I've decided to list the driver fixes in alphabetical order rather
than 'randomly'.

* axp288_adc - a recent change added a check for valid info masks when
  reading channels from consumer drivers.
* bmp280 - temperature compensation was failing to read the tfine value, hence
  causing a temperature of 0 to always be returned and incorrect presure
  measurements.
* cc10001 - Fix channel number mapping when some channels are reserved for
  remote CPUs. Fix an issue with the use of the power-up/power-down register
  (basically wrong polarity). Fix an issue due to the missinterpretting the
  return value from regulator_get_voltage. Add a delay before the start bit
  as recommended for the hardware to avoid data corruption.
* hid pressure - fix channel spec of modfiied, but no modifier (which makes no
  sense!)
* hid proximity - fix channel spec of modified, but no modifier (which makes
  no sense!). Fix a memory leak in the probe function.
* mcp320x - occasional incorrect readings on dma using spi busses due to
  cacheline corruption. Fixed by forcing ___cacheline_aligned for the buffers.
* mma9551 - buffer overrun fix (miss specified maximum length of buffers)
* mma9553 - endian fix on status message. Add an enable element for activity
  channel. Input checking for activity period to avoid rather unpredictable
  results.
* spmi-vadc - fix an overflow in the output value normalization seen on some
  boards.
* st-snesors - oops due to use of a mutex that is not yet initialized during
  probe.
* xilinx adc - Some wrong register addresses, a wrong address for vccaux
  channel, incorrect scale on VREFP and incorrect sign on VREFN.

In SPI mode the transfer buffer is locked with a mutex. However this
mutex is only initilized after the probe, but some transfer needs to
be done in the probe.

To fix this bug we move the mutex initialization at the beginning of
the device probe.

Signed-off-by: Alban Bedel <alban.bedel@avionic-design.de>
Acked-by: Denis Ciocca <denis.ciocca@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Pull HID updates from Jiri Kosina:

 - quite a few firmware fixes for RMI driver by Andrew Duggan

 - huion and uclogic drivers have been substantially overlaping in
   functionality laterly.  This redundancy is fixed by hid-huion driver
   being merged into hid-uclogic; work done by Benjamin Tissoires and
   Nikolai Kondrashov

 - i2c-hid now supports ACPI GPIO interrupts; patch from Mika Westerberg

 - Some of the quirks, that got separated into individual drivers, have
   historically had EXPERT dependency.  As HID subsystem matured (as
   well as the individual drivers), this made less and less sense.  This
   dependency is now being removed by patch from Jean Delvare

 - Logitech lg4ff driver received a couple of improvements for mode
   switching, by Michal Malý

 - multitouch driver now supports clickpads, patches by Benjamin
   Tissoires and Seth Forshee

 - hid-sensor framework received a substantial update; namely support
   for Custom and Generic pages is being added; work done by Srinivas
   Pandruvada

 - wacom driver received substantial update; it now supports
   i2c-conntected devices (Mika Westerberg), Bamboo PADs are now
   properly supported (Benjamin Tissoires), much improved battery
   reporting (Jason Gerecke) and pen proximity cleanups (Ping Cheng)

 - small assorted fixes and device ID additions

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: (68 commits)
  HID: sensor: Update document for custom sensor
  HID: sensor: Custom and Generic sensor support
  HID: debug: fix error handling in hid_debug_events_read()
  Input - mt: Fix input_mt_get_slot_by_key
  HID: logitech-hidpp: fix error return code
  HID: wacom: Add support for Cintiq 13HD Touch
  HID: logitech-hidpp: add a module parameter to keep firmware gestures
  HID: usbhid: yet another mouse with ALWAYS_POLL
  HID: usbhid: more mice with ALWAYS_POLL
  HID: wacom: set stylus_in_proximity before checking touch_down
  HID: wacom: use wacom_wac_finger_count_touches to set touch_down
  HID: wacom: remove hardcoded WACOM_QUIRK_MULTI_INPUT
  HID: pidff: effect can't be NULL
  HID: add quirk for PIXART OEM mouse used by HP
  HID: add HP OEM mouse to quirk ALWAYS_POLL
  HID: wacom: ask for a in-prox report when it was missed
  HID: hid-sensor-hub: Fix sparse warning
  HID: hid-sensor-hub: fix attribute read for logical usage id
  HID: plantronics: fix Kconfig default
  HID: pidff: support more than one concurrent effect
  ...

Conflicts:
	drivers/iio/common/hid-sensors/hid-sensor-trigger.c
	include/linux/hid-sensor-hub.h

Place driver on standby mode on error in order to prevent wasting
power. Move standby function above to be seen by the new call.

Signed-off-by: Cristina Opriceana <cristina.opriceana@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ak8975 depends on I2C and GPIOLIB, so any symbols that selects
ak8975 must have the same dependency, or we get build errors:

drivers/iio/magnetometer/ak8975.c: In function 'ak8975_who_i_am':
drivers/iio/magnetometer/ak8975.c:393:2: error: implicit declaration of function 'i2c_smbus_read_i2c_block_data' [-Werror=implicit-function-declaration]
  ret = i2c_smbus_read_i2c_block_data(client, AK09912_REG_WIA1,
  ^
drivers/iio/magnetometer/ak8975.c: In function 'ak8975_set_mode':
drivers/iio/magnetometer/ak8975.c:431:2: error: implicit declaration of function 'i2c_smbus_write_byte_data' [-Werror=implicit-function-declaration]
  ret = i2c_smbus_write_byte_data(data->client,

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 57e73a423b1e85 ("iio: ak8975: add ak09911 and ak09912 support")
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Add additional flag to read in async mode. In this mode the caller will get
reply via registered callback for capture_sample. Callbacks can be registered
using sensor_hub_register_callback function. The usage id parameter of the
capture_sample can be matched with the usage id of the requested attribute.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

Added AK8963 in the id table. Unfortunately some commercial devices
using caps version ak8963.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Use common hid sensor iio pm functions. Also the poll time read and
wait is part of power up function of hid sensor iio pm function, so
remove from the client drivers.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>