treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 194

Based on 1 normalized pattern(s):

license terms gnu general public license gpl version 2

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 161 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170027.447718015@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

iio: trigger: stm32-timer: fix build issue when disabled

This fixes a build issue when CONFIG_IIO_STM32_TIMER_TRIGGER isn't set but
used in stm32-dfsdm-adc driver (e.g. CONFIG_STM32_DFSDM_ADC is set):
ERROR: "is_stm32_timer_trigger" [drivers/iio/adc/stm32-dfsdm-adc.ko]
undefined!

There are two possible options to fix this issue:
- select IIO_STM32_TIMER_TRIGGER along with CONFIG_STM32_DFSDM_ADC.
This is what's being done currently for CONFIG_STM32_ADC.
- stub "is_stm32_timer_trigger" function

Choice is made to stub this function as suggested in [1]. This is also
inspired by similar "is_stm32_lptim_trigger" function (see [2]) in
include/linux/iio/timer/stm32-lptim-trigger.h

[1]
https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1977377.html
[2] https://lkml.org/lkml/2017/9/10/124

Fixes: 11646e81d775 ("iio: adc: stm32-dfsdm: add support for buffer modes")

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Fix-suggested-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: trigger: stm32-timer: add output compare triggers

Add output compare trigger sources available on some instances.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: trigger: stm32-timer: add support for STM32H7

Add support for STM32H7 timer triggers:
- Add new valids_table
- Introduce compatible, with configuration data
- Extend up to 15 timers, available on STM32H7

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: stm32 trigger: Add support for TRGO2 triggers

Add support for TRGO2 trigger that can be found on STM32F7.
Add additional master modes supported by TRGO2.
Register additional "tim[1/8]_trgo2" triggers for timer1 & timer8.
Detect TRGO2 timer capability (master mode selection 2).

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Acked-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

iio: Add STM32 timer trigger driver

Timers IPs can be used to generate triggers for other IPs like
DAC or ADC.
Each trigger may result of timer internals signals like counter enable,
reset or edge, this configuration could be done through "master_mode"
device attribute.

Since triggers could be used by DAC or ADC their names are defined
in include/ nux/iio/timer/stm32-timer-trigger.h and is_stm32_iio_timer_trigger
function could be used to check if the trigger is valid or not.

"trgo" trigger have a "sampling_frequency" attribute which allow to configure
timer sampling frequency.

version 8:
- change kernel version from 4.10 to 4.11 in ABI documentation

version 7:
- remove all iio_device related code
- move driver into trigger directory

version 5:
- simplify tables of triggers
- only create an IIO device when needed

version 4:
- get triggers configuration from "reg" in DT
- add tables of triggers
- sampling frequency is enable/disable when writing in trigger
sampling_frequency attribute
- no more use of interruptions

version 3:
- change compatible to "st,stm32-timer-trigger"
- fix attributes access right
- use string instead of int for master_mode and slave_mode
- document device attributes in sysfs-bus-iio-timer-stm32

version 2:
- keep only one compatible
- use st,input-triggers-names and st,output-triggers-names
to know which triggers are accepted and/or create by the device

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>