Implement .apply callback and drop the legacy callbacks(enable, disable,
config, set_polarity). In .apply() check for the current hardware status
before changing the PWM configuration.
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Only the Timer control register(TCLR) cannot be updated when the timer
is running. Registers like Counter register (TCRR), loader register
(TLDR) and match register (TMAR) can be updated while the counter is
running. Since TCLR is not updated in pwm_omap_dmtimer_config(), do not
stop the timer for period/duty_cycle update.
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
To configure DM timer in PWM mode the following needs to be set in
OMAP_TIMER_CTRL_REG using set_pwm callback:
- Set toggle mode on PORTIMERPWM output pin
- Set trigger on overflow and match on PORTIMERPWM output pin.
- Set auto reload
This is a one time configuration and needs to be set before the start of
the DM timer. But the current driver tries to set the same configuration
for every period/duty cycle update, which is not needed. So move the PWM
setup before enabling timer and do not update it in
pwm_omap_dmtimer_config().
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Update the description with a brief about how PWM is generated using
OMAP DM timer and add limitations for the PWM generations. Also add a
link to the reference manual.
Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
pwm_omap_dmtimer.h is used only:
- to typedef struct omap_dm_timer to pwm_omap_dmtimer
- for macro PWM_OMAP_DMTIMER_TRIGGER_OVERFLOW_AND_COMPARE
Rest of the file is pretty mush unsed. So reuse omap_dm_timer
and OMAP_TIMER_TRIGGER_OVERFLOW_AND_COMPARE in pwm-omap-dmtimer.c
and delete the header file.
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
dm timer ops set_load() api allows to configure the load value and to
set the auto reload feature. But auto reload feature is independent of
load value and should be part of configuring pwm. This way pwm can be
disabled by disabling auto reload feature using set_pwm() so that the
current pwm cycle will be completed. Else pwm disabling causes the
cycle to be stopped abruptly.
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200305082715.15861-7-lokeshvutla@ti.com
This was found by coccicheck:
drivers/pwm/pwm-omap-dmtimer.c:304:2-8: ERROR: missing put_device;
call of_find_device_by_node on line 255, but without a corresponding
object release within this function.
Reported-by: Markus Elfring <elfring@users.sourceforge.net>
Fixes: 6604c6556d ("pwm: Add PWM driver for OMAP using dual-mode timers")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Instead of doing error handling in the middle of ->probe(), move error
handling and freeing the reference to timer to the end.
This fixes a resource leak as dm_timer wasn't freed when allocating
*omap failed.
Implementation note: The put: label was never reached without a goto and
ret being unequal to 0, so the removed return statement is fine.
Fixes: 6604c6556d ("pwm: Add PWM driver for OMAP using dual-mode timers")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
In the old code (e.g.) mutex_destroy() was called before
pwmchip_remove(). Between these two calls it is possible that a PWM
callback is used which tries to grab the mutex.
Fixes: 6604c6556d ("pwm: Add PWM driver for OMAP using dual-mode timers")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Based on 2 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If a pwm-omap-dmtimer is probed before the dmtimer it uses, the platform
data won't be set yet.
Fixes: ac30751df9 ("ARM: OMAP: pdata-quirks: Remove unused timer pdata")
Cc: <stable@vger.kernel.org> # 4.17+
Signed-off-by: David Rivshin <drivshin@allworx.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Tested-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Ladislav Michl <ladis@linux-mips.org>
Tested-by: Andreas Kemnade <andreas@kemnade.info>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
OMAP GP timers can have different input clocks that allow different PWM
frequencies. However, there is no other way of setting the clock source but
through clocks or clock-names properties of the timer itself. This limits
PWM functionality to only the frequencies allowed by the particular clock
source. Allowing setting the clock source by PWM rather than by timer
allows different PWMs to have different ranges by not hard-wiring the clock
source to the timer.
Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Use pwm_get/set_xxx() helpers instead of directly accessing the pwm->xxx
field. Doing that will ease adaptation of the PWM framework to support
atomic update.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
After going through the math and constraints checking to compute load
and match values, it is helpful to know what the resultant period and
duty cycle are.
Signed-off-by: David Rivshin <drivshin@allworx.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
When converting period and duty_cycle from nanoseconds to fclk cycles,
the error introduced by the integer division can be appreciable, especially
in the case of slow fclk or short period. Use DIV_ROUND_CLOSEST_ULL() so
that the error is kept to +/- 0.5 clock cycles.
Fixes: 6604c6556d ("pwm: Add PWM driver for OMAP using dual-mode timers")
Signed-off-by: David Rivshin <drivshin@allworx.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Add sanity checking to ensure that we do not program load or match values
that are out of range if a user requests period or duty_cycle values which
are not achievable. The match value cannot be less than the load value (but
can be equal), and neither can be 0xffffffff. This means that there must be
at least one fclk cycle between load and match, and another between match
and overflow.
Fixes: 6604c6556d ("pwm: Add PWM driver for OMAP using dual-mode timers")
Signed-off-by: David Rivshin <drivshin@allworx.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
[thierry.reding@gmail.com: minor coding style cleanups]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Fix the calculation of load_value and match_value. Currently they
are slightly too low, which produces a noticeably wrong PWM rate with
sufficiently short periods (i.e. when 1/period approaches clk_rate/2).
Example:
clk_rate=32768Hz, period=122070ns, duty_cycle=61035ns (8192Hz/50% PWM)
Correct values: load = 0xfffffffc, match = 0xfffffffd
Current values: load = 0xfffffffa, match = 0xfffffffc
effective PWM: period=183105ns, duty_cycle=91553ns (5461Hz/50% PWM)
Fixes: 6604c6556d ("pwm: Add PWM driver for OMAP using dual-mode timers")
Signed-off-by: David Rivshin <drivshin@allworx.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Tested-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
"omap" is NULL so we can't dereference it.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Adds support for using a OMAP dual-mode timer with PWM capability
as a Linux PWM device. The driver controls the timer by using the
dmtimer API.
Add a platform_data structure for each pwm-omap-dmtimer nodes containing
the dmtimers functions in order to get driver not rely on platform
specific functions.
Cc: Grant Erickson <marathon96@gmail.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Joachim Eastwood <manabian@gmail.com>
Suggested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Tony Lindgren <tony@atomide.com>
[thierry.reding@gmail.com: coding style bikeshed, fix timer leak]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Lokesh Vutla
Uwe Kleine-König
Thomas Gleixner
David Rivshin
Keerthy
Ivaylo Dimitrov
Boris Brezillon
Dan Carpenter
Neil Armstrong