Re: [PATCH v9 2/4] pwm: opencores: Add PWM driver support

[Rob Herring]

On Fri, Dec 8, 2023 at 3:42 AM William Qiu <william.qiu@xxxxxxxxxxxxxxxx> wrote:
>
> Add driver for OpenCores PWM Controller. And add compatibility code
> which based on StarFive SoC.
>
> Co-developed-by: Hal Feng <hal.feng@xxxxxxxxxxxxxxxx>
> Signed-off-by: Hal Feng <hal.feng@xxxxxxxxxxxxxxxx>
> Signed-off-by: William Qiu <william.qiu@xxxxxxxxxxxxxxxx>
> ---
>  MAINTAINERS              |   7 ++
>  drivers/pwm/Kconfig      |  12 ++
>  drivers/pwm/Makefile     |   1 +
>  drivers/pwm/pwm-ocores.c | 229 +++++++++++++++++++++++++++++++++++++++
>  4 files changed, 249 insertions(+)
>  create mode 100644 drivers/pwm/pwm-ocores.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 788be9ab5b73..7a11a22da09e 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -16204,6 +16204,13 @@ F:     Documentation/i2c/busses/i2c-ocores.rst
>  F:     drivers/i2c/busses/i2c-ocores.c
>  F:     include/linux/platform_data/i2c-ocores.h
>
> +OPENCORES PWM DRIVER
> +M:     William Qiu <william.qiu@xxxxxxxxxxxxxxxx>
> +M:     Hal Feng <hal.feng@xxxxxxxxxxxxxxxx>
> +S:     Supported
> +F:     Documentation/devicetree/bindings/pwm/opencores,pwm.yaml
> +F:     drivers/pwm/pwm-ocores.c
> +
>  OPENRISC ARCHITECTURE
>  M:     Jonas Bonn <jonas@xxxxxxxxxxxx>
>  M:     Stefan Kristiansson <stefan.kristiansson@xxxxxxxxxxxxx>
> diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
> index 4b956d661755..d87e1bb350ba 100644
> --- a/drivers/pwm/Kconfig
> +++ b/drivers/pwm/Kconfig
> @@ -444,6 +444,18 @@ config PWM_NTXEC
>           controller found in certain e-book readers designed by the original
>           design manufacturer Netronix.
>
> +config PWM_OCORES
> +       tristate "OpenCores PWM support"
> +       depends on HAS_IOMEM && OF
> +       depends on COMMON_CLK && RESET_CONTROLLER
> +       depends on ARCH_STARFIVE || COMPILE_TEST
> +       help
> +         If you say yes to this option, support will be included for the
> +         OpenCores PWM. For details see https://opencores.org/projects/ptc.
> +
> +         To compile this driver as a module, choose M here: the module
> +         will be called pwm-ocores.
> +
>  config PWM_OMAP_DMTIMER
>         tristate "OMAP Dual-Mode Timer PWM support"
>         depends on OF
> diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
> index c5ec9e168ee7..517c4f643058 100644
> --- a/drivers/pwm/Makefile
> +++ b/drivers/pwm/Makefile
> @@ -40,6 +40,7 @@ obj-$(CONFIG_PWM_MICROCHIP_CORE)      += pwm-microchip-core.o
>  obj-$(CONFIG_PWM_MTK_DISP)     += pwm-mtk-disp.o
>  obj-$(CONFIG_PWM_MXS)          += pwm-mxs.o
>  obj-$(CONFIG_PWM_NTXEC)                += pwm-ntxec.o
> +obj-$(CONFIG_PWM_OCORES)       += pwm-ocores.o
>  obj-$(CONFIG_PWM_OMAP_DMTIMER) += pwm-omap-dmtimer.o
>  obj-$(CONFIG_PWM_PCA9685)      += pwm-pca9685.o
>  obj-$(CONFIG_PWM_PXA)          += pwm-pxa.o
> diff --git a/drivers/pwm/pwm-ocores.c b/drivers/pwm/pwm-ocores.c
> new file mode 100644
> index 000000000000..996ca3805901
> --- /dev/null
> +++ b/drivers/pwm/pwm-ocores.c
> @@ -0,0 +1,229 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * OpenCores PWM Driver
> + *
> + * https://opencores.org/projects/ptc
> + *
> + * Copyright (C) 2018-2023 StarFive Technology Co., Ltd.
> + *
> + * Limitations:
> + * - The hardware only do inverted polarity.
> + * - The hardware minimum period / duty_cycle is (1 / pwm_apb clock frequency) ns.
> + * - The hardware maximum period / duty_cycle is (U32_MAX / pwm_apb clock frequency) ns.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>

You probably don't need this header and the implicit includes it makes
are dropped now in linux-next. Please check what you actually need and
make them explicit.

Rob