Messages in this thread | ![/](/images/icornerl.gif) | | Date | Mon, 19 Dec 2022 14:30:34 +0100 | From | Uwe Kleine-König <> | Subject | Re: [PATCH v4 2/4] pwm: Add Apple PWM controller |
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On Fri, Dec 09, 2022 at 02:13:11PM +0300, Sasha Finkelstein wrote: > Adds the Apple PWM controller driver. > > Signed-off-by: Sasha Finkelstein <fnkl.kernel@gmail.com> > Acked-by: Sven Peter <sven@svenpeter.dev> > --- > drivers/pwm/Kconfig | 12 ++++ > drivers/pwm/Makefile | 1 + > drivers/pwm/pwm-apple.c | 150 ++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 163 insertions(+) > create mode 100644 drivers/pwm/pwm-apple.c > > diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig > index 60d13a949bc5..c3be11468414 100644 > --- a/drivers/pwm/Kconfig > +++ b/drivers/pwm/Kconfig > @@ -51,6 +51,18 @@ config PWM_AB8500 > To compile this driver as a module, choose M here: the module > will be called pwm-ab8500. > > +config PWM_APPLE > + tristate "Apple SoC PWM support" > + depends on ARCH_APPLE || COMPILE_TEST > + help > + Generic PWM framework driver for PWM controller present on > + Apple SoCs > + > + Say Y here if you have an ARM Apple laptop, otherwise say N > + > + To compile this driver as a module, choose M here: the module > + will be called pwm-apple. > + > config PWM_ATMEL > tristate "Atmel PWM support" > depends on ARCH_AT91 || COMPILE_TEST > diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile > index 7bf1a29f02b8..19899b912e00 100644 > --- a/drivers/pwm/Makefile > +++ b/drivers/pwm/Makefile > @@ -2,6 +2,7 @@ > obj-$(CONFIG_PWM) += core.o > obj-$(CONFIG_PWM_SYSFS) += sysfs.o > obj-$(CONFIG_PWM_AB8500) += pwm-ab8500.o > +obj-$(CONFIG_PWM_APPLE) += pwm-apple.o > obj-$(CONFIG_PWM_ATMEL) += pwm-atmel.o > obj-$(CONFIG_PWM_ATMEL_HLCDC_PWM) += pwm-atmel-hlcdc.o > obj-$(CONFIG_PWM_ATMEL_TCB) += pwm-atmel-tcb.o > diff --git a/drivers/pwm/pwm-apple.c b/drivers/pwm/pwm-apple.c > new file mode 100644 > index 000000000000..a85fecb20105 > --- /dev/null > +++ b/drivers/pwm/pwm-apple.c > @@ -0,0 +1,150 @@ > +// SPDX-License-Identifier: GPL-2.0 OR MIT > +/* > + * Driver for the Apple SoC PWM controller > + * > + * Copyright The Asahi Linux Contributors > + * > + * Limitations: > + * - The writes to cycle registers are shadowed until a write to > + * the control register. > + */ > + > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/of_device.h> > +#include <linux/platform_device.h> > +#include <linux/pwm.h> > +#include <linux/io.h> > +#include <linux/clk.h> > +#include <linux/pm_runtime.h> > +#include <linux/math64.h> > + > +#define APPLE_PWM_CONTROL 0x00 > +#define APPLE_PWM_ON_CYCLES 0x1c > +#define APPLE_PWM_OFF_CYCLES 0x18 > + > +#define APPLE_CTRL_ENABLE BIT(0) > +#define APPLE_CTRL_MODE BIT(2) > +#define APPLE_CTRL_UPDATE BIT(5) > +#define APPLE_CTRL_TRIGGER BIT(9) > +#define APPLE_CTRL_INVERT BIT(10) > +#define APPLE_CTRL_OUTPUT_ENABLE BIT(14) > + > +struct apple_pwm { > + struct pwm_chip chip; > + void __iomem *base; > + u64 clkrate; > +}; > + > +static inline struct apple_pwm *to_apple_pwm(struct pwm_chip *chip) > +{ > + return container_of(chip, struct apple_pwm, chip); > +} > + > +static int apple_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, > + const struct pwm_state *state) > +{ > + struct apple_pwm *fpwm; > + u64 on_cycles, off_cycles; > +
polarity handling is missing here and in .get_state(). I assume you want:
if (state->polarity == PWM_POLARITY_INVERSED) return -EINVAL;
here and
state->polarity = PWM_POLARITY_NORMAL;
in .get_state().
> + fpwm = to_apple_pwm(chip); > + if (state->enabled) { > + on_cycles = mul_u64_u64_div_u64(fpwm->clkrate, > + state->duty_cycle, NSEC_PER_SEC); > + if (on_cycles > 0xFFFFFFFF) > + return -ERANGE; > + > + off_cycles = mul_u64_u64_div_u64(fpwm->clkrate, > + state->period, NSEC_PER_SEC) - on_cycles; > + if (off_cycles > 0xFFFFFFFF) > + return -ERANGE; > + > + writel(on_cycles, fpwm->base + APPLE_PWM_ON_CYCLES); > + writel(off_cycles, fpwm->base + APPLE_PWM_OFF_CYCLES); > + writel(APPLE_CTRL_ENABLE | APPLE_CTRL_OUTPUT_ENABLE | APPLE_CTRL_UPDATE, > + fpwm->base + APPLE_PWM_CONTROL); > + } else { > + writel(0, fpwm->base + APPLE_PWM_CONTROL); > + } > + return 0; > +}
Best regards Uwe
-- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | https://www.pengutronix.de/ | [unhandled content-type:application/pgp-signature] | ![\](/images/icornerr.gif) |