Enable the FORCE_ALIGN flag by default in the AXI PWMGEN driver. This
flag makes the behavior of the PWM output consistent with the
description at the top of the driver file.
* Limitations:
* - The writes to registers for period and duty are shadowed until
* LOAD_CONFIG is written to AXI_PWMGEN_REG_RSTN, at which point
* they take effect.
* - Writing LOAD_CONFIG also has the effect of re-synchronizing all
* enabled channels, which could cause glitching on other channels. It
* is therefore expected that channels are assigned harmonic periods
* and all have a single user coordinating this.
Without this flag, the PWM output does not change until the period of
all PWM output channels has run out, which makes the PWM impossible to
use in some cases because it takes too long to change the output.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20241009-pwm-axi-pwmgen-enable-force_align-v1-2-5d6ad8cbf5b4@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Rename the 0x10 register from REG_CONFIG to REG_RSTN. Also rename the
associated bit macros accordingly.
While touching this, move the bit macros close to the register address
macro for better organization.
According to [1], the name of the 0x10 register is REG_RSTN, and there
is a different register named REG_CONFIG (0x18). So we should not be
using REG_CONFIG for the 0x10 register to avoid confusion.
[1]: http://analogdevicesinc.github.io/hdl/library/axi_pwm_gen/index.html
Signed-off-by: David Lechner <dlechner@baylibre.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20241009-pwm-axi-pwmgen-enable-force_align-v1-1-5d6ad8cbf5b4@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Support a new abstraction for pwm configuration that allows to specify
the time between start of period and the raising edge of the signal
("duty offset").
This is used in a patch series by Trevor Gamblin for triggering an ADC
conversion and afterwards read out the result. See
https://lore.kernel.org/linux-iio/20240909-ad7625_r1-v5-0-60a397768b25@baylibre.com/
for more details.
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Merge tag 'pwm/duty_offset-for-6.13-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux
pwm: Support for duty_offset
Support a new abstraction for pwm configuration that allows to specify
the time between start of period and the raising edge of the signal
("duty offset").
This is used in a patch series by Trevor Gamblin for triggering an ADC
conversion and afterwards read out the result. See
https://lore.kernel.org/linux-iio/20240909-ad7625_r1-v5-0-60a397768b25@baylibre.com/
for more details.
Compared to direct calls to pwmchip_get_drvdata() a dedicated function
has two upsides: A better name and the right type. So the code becomes
easier to read and the new function is harder to use wrongly.
Another side effect (which is the secret motivation for this patch, but
shhh) is that the driver becomes a bit easier to backport to kernel
versions that don't have devm_pwmchip_alloc() yet.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Reviewed-by: Trevor Gamblin <tgamblin@baylibre.com>
Link: https://lore.kernel.org/r/20240923125418.16558-2-u.kleine-koenig@baylibre.com
[ukleinek: added an * to the new function's prototype to make the compiler happy]
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
This was missed in the basic driver and is useful for debug, so add it.
Example regmap output before the patch:
|root@zed-tg:~# cat /sys/kernel/debug/regmap/44a60000.pwm/registers
|0: 00020100
And with it:
|root@zed-tg:~# cat /sys/kernel/debug/regmap/44a60000.pwm/registers
|00: 00020100
|04: 00000000
|08: 00000000
|0c: 601a3471
|10: 00000000
|14: 00000002
|18: 00000001
|1c: 00000000
|...
Signed-off-by: Trevor Gamblin <tgamblin@baylibre.com>
Link: https://lore.kernel.org/r/20240711125743.3956935-1-tgamblin@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Add support for the Analog Devices AXI PWM Generator. This device is an
FPGA-implemented peripheral used as PWM signal generator and can be
interfaced with AXI4. The register map of this peripheral makes it
possible to configure the period and duty cycle of the output signal.
Link: https://analogdevicesinc.github.io/hdl/library/axi_pwm_gen/index.html
Co-developed-by: Sergiu Cuciurean <sergiu.cuciurean@analog.com>
Signed-off-by: Sergiu Cuciurean <sergiu.cuciurean@analog.com>
Co-developed-by: David Lechner <dlechner@baylibre.com>
Signed-off-by: David Lechner <dlechner@baylibre.com>
Signed-off-by: Drew Fustini <dfustini@baylibre.com>
Acked-by: Nuno Sa <nuno.sa@analog.com>
Co-developed-by: Trevor Gamblin <tgamblin@baylibre.com>
Signed-off-by: Trevor Gamblin <tgamblin@baylibre.com>
Link: https://lore.kernel.org/r/20240605203507.1934434-3-tgamblin@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
