Allwinner A64 is capable of a direct clock output on PWM (see A64 User
Manual chapter 3.10). Add support for this in the sun4i PWM driver.
Signed-off-by: Peter Vasil <peter.vasil@gmail.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
'needs_delay' does now always evaluate to true, so remove all
occurrences.
Signed-off-by: Pascal Roeleven <dev@pascalroeleven.nl>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
GCC can't always determine that the duty, period and prescaler values
are initialized when returning from sun4i_pwm_calculate(), so help out a
little by initializing them to 0.
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The variable pval is only used in a single block in the function
sun4i_pwm_calculate(). So declare it in a more local scope to simplify
the function for humans and compilers.
While at it also simplify assignment to pval.
While the diffstat for this patch is negative for this patch I still
thing the advantage of having a narrower scope is beneficial.
In my compiler / .config setup (gcc 8.2.1, arm/imx_v6_v7_defconfig +
COMPILE_TEST + PWM_SUN4I) this change doesn't result in any binary
changes.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Fix inconsistent IS_ERR and PTR_ERR in sun4i_pwm_probe().
The proper pointers to be passed as arguments are pwm->clk and pwm->bus_clk.
This bug was detected with the help of Coccinelle.
Fixes: b8d74644f3 ("pwm: sun4i: Prefer "mod" clock to unnamed")
Fixes: 5b090b430d ("pwm: sun4i: Add an optional probe for bus clock")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
pwm_calculate() calls clk_get_rate() while holding a spin_lock().
This create an issue as clk_get_rate() may sleep.
Move pwm_calculate() out of this spin_lock().
Fixes: c32c5c50d4 ("pwm: sun4i: Switch to atomic PWM")
Reported-by: Alexander Finger <alex.mobigo@gmail.com>
Sugested-by: Vasily Khoruzhick <anarsoul@gmail.com>
Tested-by: Alexander Finger <alex.mobigo@gmail.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Clément Péron <peron.clem@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Now that sun4i PWM driver supports deasserting reset line and enabling
bus clock, support for H6 PWM can be added.
Note that while H6 PWM has two channels, only first one is wired to
output pin. Second channel is used as a clock source to companion AC200
chip which is bundled into same package.
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Clément Péron <peron.clem@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
PWM core has an option to bypass whole logic and output unchanged source
clock as PWM output. This is achieved by enabling bypass bit.
Note that when bypass is enabled, no other setting has any meaning, not
even enable bit.
This mode of operation is needed to achieve high enough frequency to
serve as clock source for AC200 chip which is integrated into same
package as H6 SoC.
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Clément Péron <peron.clem@gmail.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Bypass mode will require to be re-calculated when the pwm state
is changed.
Remove the condition so pwm_sun4i_calculate is always called.
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Clément Péron <peron.clem@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
H6 PWM core needs bus clock to be enabled in order to work.
Add an optional probe for it.
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Clément Péron <peron.clem@gmail.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
New device tree bindings called the source clock of the module
"mod" when several clocks are defined.
Try to get a clock called "mod" if nothing is found try to get
an unnamed clock.
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Clément Péron <peron.clem@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
H6 PWM core needs deasserted reset line in order to work.
Add an optional probe for it.
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Clément Péron <peron.clem@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Since 5.4-rc1, pwm_apply_state calls ->get_state after ->apply
if available, and this revealed an issue with integer precision
when calculating duty_cycle and period for the currently set
state in ->get_state callback.
This issue manifested in broken backlight on several Allwinner
based devices.
Previously this worked, because ->apply updated the passed state
directly.
Fixes: deb9c462f4 ("pwm: sun4i: Don't update the state for the caller of pwm_apply_state")
Signed-off-by: Ondrej Jirman <megous@megous.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Variable pval is being assigned a value that is never read. The
assignment is redundant and hence can be removed.
Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
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>
The pwm-sun4i driver is one of only three PWM drivers which updates the
state for the caller of pwm_apply_state(). This might have surprising
results if the caller reuses the values expecting them to still
represent the same state.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Based on 1 normalized pattern(s):
licensed under gplv2
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 99 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170027.163048684@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
At the moment we assign our supported compatible strings to a respective
instance of our sun4i_pwm_data structure, even though some of them
are the same.
To avoid further clutter, split out the three different combinations of
features we have at the moment and name them accordingly.
This should make it more obvious which compatible string to use for new
SoCs.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Commit a054c4d684 ("pwm: sun4i: Drop legacy callbacks") dropped the
only user of the .has_rdy member in our sun4i_pwm_data struct.
Consequently we don't need to store this anymore for the various SoCs,
which paves the way for further simplifications.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Correctly extract the prescaler value from CTRL_REG before comparing it
to PWM_PRESCAL_MASK.
Also, check that both PWM_CLK_GATING and PWM_EN to ensure the PWM is
enabled instead of relying on only one of those.
Fixes: 93e0dfb2c5 ("pwm: sun4i: Improve hardware read out")
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The usage of of_device_get_match_data reduce the code size a bit.
Furthermore, it prevents an improbable dereference when
of_match_device() returns NULL.
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Switch the driver to atomic PWM. This makes it easier to wait a proper
amount of time when changing the duty cycle before disabling the channel
(main use case is switching the duty cycle to 0 before disabling).
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Implement .get_state instead of only reading the polarity at probe time.
This allows to get the proper state, period and duty cycle.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
All PWM devices have been marked as "might sleep" since v4.5, there is
no longer a need to differentiate on a per-chip basis.
Signed-off-by: Thierry Reding <thierry.reding@gmail.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>
This patch changes no code, it just fixes the whitespacing. Operators
should be separated from operands by a single space.
Signed-off-by: Olliver Schinagl <oliver@schinagl.nl>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The PWM controller on sun5i SoCs is identical to the one found on sun7i
SoCs. On the A13 package only one of the 2 pins is routed to the outside,
so only advertise one PWM channel there.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This adds a generic PWM framework driver for the PWM controller
found on Allwinner SoCs.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
