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>
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>
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>
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>