It is surprising for a PWM consumer when the variable holding the
requested state is modified by pwm_apply_state(). Consider for example a
driver doing:
#define PERIOD 5000000
#define DUTY_LITTLE 10
...
struct pwm_state state = {
.period = PERIOD,
.duty_cycle = DUTY_LITTLE,
.polarity = PWM_POLARITY_NORMAL,
.enabled = true,
};
pwm_apply_state(mypwm, &state);
...
state.duty_cycle = PERIOD / 2;
pwm_apply_state(mypwm, &state);
For sure the second call to pwm_apply_state() should still have
state.period = PERIOD and not something the hardware driver chose for a
reason that doesn't necessarily apply to the second call.
So declare the state argument as a pointer to a const type and adapt all
drivers' .apply callbacks.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Since the rcar_pwm_apply() has already checked whether state->enabled
is set or not, this patch removes a redundant condition.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
According to the Documentation/pwm.txt, all PWM consumers should
implement power management instead of the PWM driver. So, this
patch removes suspend/resume support.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The rcar_pwm_get_clock_division() has a loop to calculate the divider,
but the value of div should be calculatable without a loop. So, this
patch improves it.
This algorithm is suggested by Uwe Kleine-König and Laurent Pinchart.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This patch removes legacy APIs. Since rcar_pwm_{en,dis}able() functions
are reused on "atomic" API, this patch changes the arguments of these
functions. No change in behavior.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
To remove legacy API related functions in the future, this patch
uses "atomic" related function instead. No change in behavior.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This patch adds support for "atomic" API. This behavior differs with
legacy APIs a little.
Legacy APIs:
The PWMCNT register will be updated in rcar_pwm_config() even if
the PWM state is disabled.
Atomic API:
The PWMCNT register will be updated in rcar_pwm_apply() only if
the PWM state is enabled. Otherwize, if a PWM runs with 30% duty
cycles and the pwm_apply_state() is called with state->enabled = 0,
->duty_cycle = 60 and ->period = 100, this is possible to output
a 60% duty cycle.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
We should get drvdata from struct device directly. Going via
platform_device is an unneeded step back and forth.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Runtime PM API (pm_runtime_get_sync/pm_runtime_put) should be used
to control module clock instead of clk_prepare_enable and
clk_disable_unprepare.
Signed-off-by: Hien Dang <hien.dang.eb@renesas.com>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This patch fixes an issue that is possible to set mismatch value to duty
for R-Car PWM if we input the following commands:
# cd /sys/class/pwm/<pwmchip>/
# echo 0 > export
# cd pwm0
# echo 30 > period
# echo 30 > duty_cycle
# echo 0 > duty_cycle
# cat duty_cycle
0
# echo 1 > enable
--> Then, the actual duty_cycle is 30, not 0.
So, this patch adds a condition into rcar_pwm_config() to fix this
issue.
Signed-off-by: Ryo Kodama <ryo.kodama.vz@renesas.com>
[shimoda: revise the commit log and add Fixes and Cc tags]
Fixes: ed6c1476bf ("pwm: Add support for R-Car PWM Timer")
Cc: Cc: <stable@vger.kernel.org> # v4.4+
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Commit 5c31252c4a ("pwm: Add the pwm_is_enabled() helper") introduced
a new function to test whether a PWM device is enabled or not without
manipulating PWM internal fields.
Hiding this is necessary if we want to smoothly move to the atomic PWM
config approach without impacting PWM drivers. Fix this driver to use
pwm_is_enabled() instead of directly accessing the ->flags field.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
From: Ryo Kodama <ryo.kodama.vz@renesas.com>
When period_ns is set to the same value of RCAR_PWM_MAX_CYCLE in
rcar_pwm_get_clock_division(), this function should allow such value
for improving accuracy of frequency division setting.
Signed-off-by: Ryo Kodama <ryo.kodama.vz@renesas.com>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This patch adds support for R-Car SoCs PWM Timer. The PWM timer of
R-Car H2 has 7 channels. So, we can use the channels if we describe
device tree nodes.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
