| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm
Pull pwm updates from Thierry Reding:
"This contains a couple of fixes and cleanups for the Meson and
ACPI/LPSS drivers as well as capture support for STM32.
Note that given the cross- subsystem changes, the STM32 patches were
merged through the MFD and PWM trees, both sharing an immutable
branch"
* tag 'pwm/for-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm:
pwm: stm32: Fix build warning with CONFIG_DMA_ENGINE disabled
pwm: stm32: Enforce dependency on CONFIG_MFD_STM32_TIMERS
ACPI / LPSS: Add missing prv_offset setting for byt/cht PWM devices
pwm: lpss: platform: Save/restore the ctrl register over a suspend/resume
dt-bindings: mfd: stm32-timers: Add support for dmas
pwm: simplify getting .drvdata
pwm: meson: Fix allocation of PWM channel array
|
|
Without dmaengine support, we get a harmless warning about an unused
function:
drivers/pwm/pwm-stm32.c:166:12: error: 'stm32_pwm_capture' defined but not used [-Werror=unused-function]
Changing the #ifdef to an IS_ENABLED() check shuts up that warning and
is slightly nicer to read.
Fixes: 53e38fe73f94 ("pwm: stm32: Add capture support")
Signed-off-by: Arnd Bergmann <[email protected]>
Acked-by: Fabrice Gasnier <[email protected]>
Signed-off-by: Thierry Reding <[email protected]>
|
|
This removes build warning when COMPILE_TEST=y and MFD_STM32_TIMERS=n
in drivers/pwm/pwm-stm32.c. In function 'stm32_pwm_capture' 'raw_prd' and
'raw_dty' may be used uninitialized in this function
[-Wmaybe-uninitialized]
Signed-off-by: Fabrice Gasnier <[email protected]>
Acked-by: Thierry Reding <[email protected]>
Tested-by: Randy Dunlap <[email protected]>
Signed-off-by: Lee Jones <[email protected]>
|
|
Using input prescaler, capture unit will trigger DMA once every
configurable /2, /4 or /8 events (rising edge). This helps improve
period (only) capture accuracy at high rates.
Signed-off-by: Fabrice Gasnier <[email protected]>
Reviewed-by: Benjamin Gaignard <[email protected]>
Acked-by: Thierry Reding <[email protected]>
Signed-off-by: Lee Jones <[email protected]>
|
|
Currently, capture is based on timeout window to configure prescaler.
PWM capture framework provides 1s window at the time of writing.
There's place for improvement, after input signal has been captured once:
- Finer tune counter clock prescaler, by using 1st capture result (with
arbitrary margin).
- Do a 2nd capture, with scaled capture window.
This increases accuracy, especially at high rates.
Signed-off-by: Fabrice Gasnier <[email protected]>
Reviewed-by: Benjamin Gaignard <[email protected]>
Acked-by: Thierry Reding <[email protected]>
Signed-off-by: Lee Jones <[email protected]>
|
|
Add support for PMW input mode on pwm-stm32. STM32 timers support
period and duty cycle capture as long as they have at least two PWM
channels. One capture channel is used for period (rising-edge), one
for duty-cycle (falling-edge).
When there's only one channel available, only period can be captured.
Duty-cycle is simply zero'ed in such a case.
Capture requires exclusive access (e.g. no pwm output running at the
same time, to protect common prescaler).
Timer DMA burst mode (from MFD core) is being used, to take two
snapshots of capture registers (upon each period rising edge).
Signed-off-by: Fabrice Gasnier <[email protected]>
Reviewed-by: Benjamin Gaignard <[email protected]>
Acked-by: Thierry Reding <[email protected]>
Signed-off-by: Lee Jones <[email protected]>
|
|
There may be a race, when configuring two PWM channels, with different
prescaler values, when there's no active channel yet.
Add mutex lock to avoid concurrent access on PWM apply state.
This is also precursor patch for PWM capture support.
Signed-off-by: Fabrice Gasnier <[email protected]>
Reviewed-by: Benjamin Gaignard <[email protected]>
Signed-off-by: Thierry Reding <[email protected]>
|
|
dev is never assigned or used. Remove it.
Fixes: 7edf7369205b ("pwm: Add driver for STM32 plaftorm")
Signed-off-by: Fabrice Gasnier <[email protected]>
Reviewed-by: Benjamin Gaignard <[email protected]>
Signed-off-by: Thierry Reding <[email protected]>
|
|
Add SPDX identifier to make it easier to determine the license of the
file.
Signed-off-by: Benjamin Gaignard <[email protected]>
Acked-by: Philippe Ombredanne <[email protected]>
Signed-off-by: Thierry Reding <[email protected]>
|
|
This driver adds support for PWM driver on STM32 platform.
The SoC have multiple instances of the hardware IP and each
of them could have small differences: number of channels,
complementary output, auto reload register size...
version 9:
- fix commit message header
- remove one space MODULE_ALIAS
version 8:
- fix comments done by Thierry on version 7
version 6:
- change st,breakinput parameter to make it usuable for stm32f7 too.
version 4:
- detect at probe time hardware capabilities
- fix comments done on v2 and v3
- use PWM atomic ops
version 2:
- only keep one comptatible
- use DT parameters to discover hardware block configuration
Signed-off-by: Benjamin Gaignard <[email protected]>
Acked-by: Thierry Reding <[email protected]>
Signed-off-by: Lee Jones <[email protected]>
|