[v8,2/4] pwm: opencores: Add PWM driver support
Commit Message
Add driver for OpenCores PWM Controller. And add compatibility code
which based on StarFive SoC.
Co-developed-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: William Qiu <william.qiu@starfivetech.com>
---
MAINTAINERS | 7 ++
drivers/pwm/Kconfig | 12 ++
drivers/pwm/Makefile | 1 +
drivers/pwm/pwm-ocores.c | 232 +++++++++++++++++++++++++++++++++++++++
4 files changed, 252 insertions(+)
create mode 100644 drivers/pwm/pwm-ocores.c
Comments
On Mi, 2023-11-29 at 17:27 +0800, William Qiu wrote:
> Add driver for OpenCores PWM Controller. And add compatibility code
> which based on StarFive SoC.
>
> Co-developed-by: Hal Feng <hal.feng@starfivetech.com>
> Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
> Signed-off-by: William Qiu <william.qiu@starfivetech.com>
> ---
> MAINTAINERS | 7 ++
> drivers/pwm/Kconfig | 12 ++
> drivers/pwm/Makefile | 1 +
> drivers/pwm/pwm-ocores.c | 232 +++++++++++++++++++++++++++++++++++++++
> 4 files changed, 252 insertions(+)
> create mode 100644 drivers/pwm/pwm-ocores.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 012df8ccf34e..ae6a7be47bc9 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -16206,6 +16206,13 @@ 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@starfivetech.com>
> +M: Hal Feng <hal.feng@starfivetech.com>
> +S: Supported
> +F: Documentation/devicetree/bindings/pwm/opencores,pwm.yaml
> +F: drivers/pwm/pwm-ocores.c
> +
> OPENRISC ARCHITECTURE
> M: Jonas Bonn <jonas@southpole.se>
> M: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
> 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..d96318b18570
> --- /dev/null
> +++ b/drivers/pwm/pwm-ocores.c
> @@ -0,0 +1,232 @@
> +// 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>
> +#include <linux/platform_device.h>
> +#include <linux/pwm.h>
> +#include <linux/reset.h>
> +#include <linux/slab.h>
> +
> +/* OCPWM_CTRL register bits*/
> +#define REG_OCPWM_EN BIT(0)
> +#define REG_OCPWM_ECLK BIT(1)
> +#define REG_OCPWM_NEC BIT(2)
> +#define REG_OCPWM_OE BIT(3)
> +#define REG_OCPWM_SIGNLE BIT(4)
> +#define REG_OCPWM_INTE BIT(5)
> +#define REG_OCPWM_INT BIT(6)
> +#define REG_OCPWM_CNTRRST BIT(7)
> +#define REG_OCPWM_CAPTE BIT(8)
> +
> +struct ocores_pwm_device {
> + struct pwm_chip chip;
> + struct clk *clk;
> + struct reset_control *rst;
> + const struct ocores_pwm_data *data;
> + void __iomem *regs;
> + u32 clk_rate; /* PWM APB clock frequency */
> +};
> +
> +struct ocores_pwm_data {
> + void __iomem *(*get_ch_base)(void __iomem *base, unsigned int channel);
> +};
> +
> +static inline u32 ocores_readl(struct ocores_pwm_device *ddata,
> + unsigned int channel,
> + unsigned int offset)
> +{
> + void __iomem *base = ddata->data->get_ch_base ?
> + ddata->data->get_ch_base(ddata->regs, channel) : ddata->regs;
> +
> + return readl(base + offset);
> +}
> +
> +static inline void ocores_writel(struct ocores_pwm_device *ddata,
> + unsigned int channel,
> + unsigned int offset, u32 val)
> +{
> + void __iomem *base = ddata->data->get_ch_base ?
> + ddata->data->get_ch_base(ddata->regs, channel) : ddata->regs;
> +
> + writel(val, base + offset);
> +}
> +
> +static inline struct ocores_pwm_device *chip_to_ocores(struct pwm_chip *chip)
> +{
> + return container_of(chip, struct ocores_pwm_device, chip);
> +}
> +
> +static void __iomem *starfive_jh71x0_get_ch_base(void __iomem *base,
> + unsigned int channel)
> +{
> + unsigned int offset = (channel > 3 ? 1 << 15 : 0) + (channel & 3) * 0x10;
> +
> + return base + offset;
> +}
> +
> +static int ocores_pwm_get_state(struct pwm_chip *chip,
> + struct pwm_device *pwm,
> + struct pwm_state *state)
> +{
> + struct ocores_pwm_device *ddata = chip_to_ocores(chip);
> + u32 period_data, duty_data, ctrl_data;
> +
> + period_data = ocores_readl(ddata, pwm->hwpwm, 0x8);
> + duty_data = ocores_readl(ddata, pwm->hwpwm, 0x4);
> + ctrl_data = ocores_readl(ddata, pwm->hwpwm, 0xC);
> +
> + state->period = DIV_ROUND_UP_ULL((u64)period_data * NSEC_PER_SEC, ddata->clk_rate);
> + state->duty_cycle = DIV_ROUND_UP_ULL((u64)duty_data * NSEC_PER_SEC, ddata->clk_rate);
> + state->polarity = PWM_POLARITY_INVERSED;
> + state->enabled = (ctrl_data & REG_OCPWM_EN) ? true : false;
> +
> + return 0;
> +}
> +
> +static int ocores_pwm_apply(struct pwm_chip *chip,
> + struct pwm_device *pwm,
> + const struct pwm_state *state)
> +{
> + struct ocores_pwm_device *ddata = chip_to_ocores(chip);
> + u32 ctrl_data = 0;
> + u64 period_data, duty_data;
> +
> + if (state->polarity != PWM_POLARITY_INVERSED)
> + return -EINVAL;
> +
> + ctrl_data = ocores_readl(ddata, pwm->hwpwm, 0xC);
> + ocores_writel(ddata, pwm->hwpwm, 0xC, 0);
> +
> + period_data = DIV_ROUND_DOWN_ULL(state->period * ddata->clk_rate, NSEC_PER_SEC);
> + if (period_data <= U32_MAX)
> + ocores_writel(ddata, pwm->hwpwm, 0x8, (u32)period_data);
> + else
> + return -EINVAL;
> +
> + duty_data = DIV_ROUND_DOWN_ULL(state->duty_cycle * ddata->clk_rate, NSEC_PER_SEC);
> + if (duty_data <= U32_MAX)
> + ocores_writel(ddata, pwm->hwpwm, 0x4, (u32)duty_data);
> + else
> + return -EINVAL;
> +
> + ocores_writel(ddata, pwm->hwpwm, 0xC, 0);
> +
> + if (state->enabled) {
> + ctrl_data = ocores_readl(ddata, pwm->hwpwm, 0xC);
> + ocores_writel(ddata, pwm->hwpwm, 0xC, ctrl_data | REG_OCPWM_EN | REG_OCPWM_OE);
> + }
> +
> + return 0;
> +}
> +
> +static const struct pwm_ops ocores_pwm_ops = {
> + .get_state = ocores_pwm_get_state,
> + .apply = ocores_pwm_apply,
> +};
> +
> +static const struct ocores_pwm_data jh7100_pwm_data = {
> + .get_ch_base = starfive_jh71x0_get_ch_base,
> +};
> +
> +static const struct ocores_pwm_data jh7110_pwm_data = {
> + .get_ch_base = starfive_jh71x0_get_ch_base,
> +};
> +
> +static const struct of_device_id ocores_pwm_of_match[] = {
> + { .compatible = "opencores,pwm-v1" },
> + { .compatible = "starfive,jh7100-pwm", .data = &jh7100_pwm_data},
> + { .compatible = "starfive,jh7110-pwm", .data = &jh7110_pwm_data},
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, ocores_pwm_of_match);
> +
> +static int ocores_pwm_probe(struct platform_device *pdev)
> +{
> + const struct of_device_id *id;
> + struct device *dev = &pdev->dev;
> + struct ocores_pwm_device *ddata;
> + struct pwm_chip *chip;
> + int ret;
> +
> + id = of_match_device(ocores_pwm_of_match, dev);
> + if (!id)
> + return -EINVAL;
> +
> + ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
> + if (!ddata)
> + return -ENOMEM;
> +
> + ddata->data = id->data;
> + chip = &ddata->chip;
> + chip->dev = dev;
> + chip->ops = &ocores_pwm_ops;
> + chip->npwm = 8;
> + chip->of_pwm_n_cells = 3;
> +
> + ddata->regs = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(ddata->regs))
> + return dev_err_probe(dev, PTR_ERR(ddata->regs),
> + "Unable to map IO resources\n");
> +
> + ddata->clk = devm_clk_get_enabled(dev, NULL);
> + if (IS_ERR(ddata->clk))
> + return dev_err_probe(dev, PTR_ERR(ddata->clk),
> + "Unable to get pwm's clock\n");
> +
> + ddata->rst = devm_reset_control_get_optional_exclusive(dev, NULL);
> + reset_control_deassert(ddata->rst);
You could use devm_add_action_or_reset() to add reset assertion for
driver removal and the error paths here, allowing to drop
ocores_pwm_remove() and ...
> + ddata->clk_rate = clk_get_rate(ddata->clk);
> + if (ddata->clk_rate <= 0)
> + return dev_err_probe(dev, ddata->clk_rate,
> + "Unable to get clock's rate\n");
... then this wouldn't leave the reset deasserted ...
> +
> + ret = devm_pwmchip_add(dev, chip);
> + if (ret < 0) {
> + reset_control_assert(ddata->rst);
... and this could be dropped.
> + clk_disable_unprepare(ddata->clk);
This can be dropped, devm_clk_get_enabled() already disables the clock
on probe error.
> + return dev_err_probe(dev, ret, "Could not register PWM chip\n");
> + }
> +
> + platform_set_drvdata(pdev, ddata);
> +
> + return ret;
> +}
> +
> +static void ocores_pwm_remove(struct platform_device *dev)
> +{
> + struct ocores_pwm_device *ddata = platform_get_drvdata(dev);
> +
> + reset_control_assert(ddata->rst);
> + clk_disable_unprepare(ddata->clk);
Drop as well, devm_clk_get_enabled() already disables the clock on
driver removal.
regards
Philipp
On 2023/11/29 18:25, Philipp Zabel wrote:
> On Mi, 2023-11-29 at 17:27 +0800, William Qiu wrote:
>> Add driver for OpenCores PWM Controller. And add compatibility code
>> which based on StarFive SoC.
>>
>> Co-developed-by: Hal Feng <hal.feng@starfivetech.com>
>> Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
>> Signed-off-by: William Qiu <william.qiu@starfivetech.com>
>> ---
>> MAINTAINERS | 7 ++
>> drivers/pwm/Kconfig | 12 ++
>> drivers/pwm/Makefile | 1 +
>> drivers/pwm/pwm-ocores.c | 232 +++++++++++++++++++++++++++++++++++++++
>> 4 files changed, 252 insertions(+)
>> create mode 100644 drivers/pwm/pwm-ocores.c
>>
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index 012df8ccf34e..ae6a7be47bc9 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -16206,6 +16206,13 @@ 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@starfivetech.com>
>> +M: Hal Feng <hal.feng@starfivetech.com>
>> +S: Supported
>> +F: Documentation/devicetree/bindings/pwm/opencores,pwm.yaml
>> +F: drivers/pwm/pwm-ocores.c
>> +
>> OPENRISC ARCHITECTURE
>> M: Jonas Bonn <jonas@southpole.se>
>> M: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
>> 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..d96318b18570
>> --- /dev/null
>> +++ b/drivers/pwm/pwm-ocores.c
>> @@ -0,0 +1,232 @@
>> +// 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>
>> +#include <linux/platform_device.h>
>> +#include <linux/pwm.h>
>> +#include <linux/reset.h>
>> +#include <linux/slab.h>
>> +
>> +/* OCPWM_CTRL register bits*/
>> +#define REG_OCPWM_EN BIT(0)
>> +#define REG_OCPWM_ECLK BIT(1)
>> +#define REG_OCPWM_NEC BIT(2)
>> +#define REG_OCPWM_OE BIT(3)
>> +#define REG_OCPWM_SIGNLE BIT(4)
>> +#define REG_OCPWM_INTE BIT(5)
>> +#define REG_OCPWM_INT BIT(6)
>> +#define REG_OCPWM_CNTRRST BIT(7)
>> +#define REG_OCPWM_CAPTE BIT(8)
>> +
>> +struct ocores_pwm_device {
>> + struct pwm_chip chip;
>> + struct clk *clk;
>> + struct reset_control *rst;
>> + const struct ocores_pwm_data *data;
>> + void __iomem *regs;
>> + u32 clk_rate; /* PWM APB clock frequency */
>> +};
>> +
>> +struct ocores_pwm_data {
>> + void __iomem *(*get_ch_base)(void __iomem *base, unsigned int channel);
>> +};
>> +
>> +static inline u32 ocores_readl(struct ocores_pwm_device *ddata,
>> + unsigned int channel,
>> + unsigned int offset)
>> +{
>> + void __iomem *base = ddata->data->get_ch_base ?
>> + ddata->data->get_ch_base(ddata->regs, channel) : ddata->regs;
>> +
>> + return readl(base + offset);
>> +}
>> +
>> +static inline void ocores_writel(struct ocores_pwm_device *ddata,
>> + unsigned int channel,
>> + unsigned int offset, u32 val)
>> +{
>> + void __iomem *base = ddata->data->get_ch_base ?
>> + ddata->data->get_ch_base(ddata->regs, channel) : ddata->regs;
>> +
>> + writel(val, base + offset);
>> +}
>> +
>> +static inline struct ocores_pwm_device *chip_to_ocores(struct pwm_chip *chip)
>> +{
>> + return container_of(chip, struct ocores_pwm_device, chip);
>> +}
>> +
>> +static void __iomem *starfive_jh71x0_get_ch_base(void __iomem *base,
>> + unsigned int channel)
>> +{
>> + unsigned int offset = (channel > 3 ? 1 << 15 : 0) + (channel & 3) * 0x10;
>> +
>> + return base + offset;
>> +}
>> +
>> +static int ocores_pwm_get_state(struct pwm_chip *chip,
>> + struct pwm_device *pwm,
>> + struct pwm_state *state)
>> +{
>> + struct ocores_pwm_device *ddata = chip_to_ocores(chip);
>> + u32 period_data, duty_data, ctrl_data;
>> +
>> + period_data = ocores_readl(ddata, pwm->hwpwm, 0x8);
>> + duty_data = ocores_readl(ddata, pwm->hwpwm, 0x4);
>> + ctrl_data = ocores_readl(ddata, pwm->hwpwm, 0xC);
>> +
>> + state->period = DIV_ROUND_UP_ULL((u64)period_data * NSEC_PER_SEC, ddata->clk_rate);
>> + state->duty_cycle = DIV_ROUND_UP_ULL((u64)duty_data * NSEC_PER_SEC, ddata->clk_rate);
>> + state->polarity = PWM_POLARITY_INVERSED;
>> + state->enabled = (ctrl_data & REG_OCPWM_EN) ? true : false;
>> +
>> + return 0;
>> +}
>> +
>> +static int ocores_pwm_apply(struct pwm_chip *chip,
>> + struct pwm_device *pwm,
>> + const struct pwm_state *state)
>> +{
>> + struct ocores_pwm_device *ddata = chip_to_ocores(chip);
>> + u32 ctrl_data = 0;
>> + u64 period_data, duty_data;
>> +
>> + if (state->polarity != PWM_POLARITY_INVERSED)
>> + return -EINVAL;
>> +
>> + ctrl_data = ocores_readl(ddata, pwm->hwpwm, 0xC);
>> + ocores_writel(ddata, pwm->hwpwm, 0xC, 0);
>> +
>> + period_data = DIV_ROUND_DOWN_ULL(state->period * ddata->clk_rate, NSEC_PER_SEC);
>> + if (period_data <= U32_MAX)
>> + ocores_writel(ddata, pwm->hwpwm, 0x8, (u32)period_data);
>> + else
>> + return -EINVAL;
>> +
>> + duty_data = DIV_ROUND_DOWN_ULL(state->duty_cycle * ddata->clk_rate, NSEC_PER_SEC);
>> + if (duty_data <= U32_MAX)
>> + ocores_writel(ddata, pwm->hwpwm, 0x4, (u32)duty_data);
>> + else
>> + return -EINVAL;
>> +
>> + ocores_writel(ddata, pwm->hwpwm, 0xC, 0);
>> +
>> + if (state->enabled) {
>> + ctrl_data = ocores_readl(ddata, pwm->hwpwm, 0xC);
>> + ocores_writel(ddata, pwm->hwpwm, 0xC, ctrl_data | REG_OCPWM_EN | REG_OCPWM_OE);
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static const struct pwm_ops ocores_pwm_ops = {
>> + .get_state = ocores_pwm_get_state,
>> + .apply = ocores_pwm_apply,
>> +};
>> +
>> +static const struct ocores_pwm_data jh7100_pwm_data = {
>> + .get_ch_base = starfive_jh71x0_get_ch_base,
>> +};
>> +
>> +static const struct ocores_pwm_data jh7110_pwm_data = {
>> + .get_ch_base = starfive_jh71x0_get_ch_base,
>> +};
>> +
>> +static const struct of_device_id ocores_pwm_of_match[] = {
>> + { .compatible = "opencores,pwm-v1" },
>> + { .compatible = "starfive,jh7100-pwm", .data = &jh7100_pwm_data},
>> + { .compatible = "starfive,jh7110-pwm", .data = &jh7110_pwm_data},
>> + { /* sentinel */ }
>> +};
>> +MODULE_DEVICE_TABLE(of, ocores_pwm_of_match);
>> +
>> +static int ocores_pwm_probe(struct platform_device *pdev)
>> +{
>> + const struct of_device_id *id;
>> + struct device *dev = &pdev->dev;
>> + struct ocores_pwm_device *ddata;
>> + struct pwm_chip *chip;
>> + int ret;
>> +
>> + id = of_match_device(ocores_pwm_of_match, dev);
>> + if (!id)
>> + return -EINVAL;
>> +
>> + ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
>> + if (!ddata)
>> + return -ENOMEM;
>> +
>> + ddata->data = id->data;
>> + chip = &ddata->chip;
>> + chip->dev = dev;
>> + chip->ops = &ocores_pwm_ops;
>> + chip->npwm = 8;
>> + chip->of_pwm_n_cells = 3;
>> +
>> + ddata->regs = devm_platform_ioremap_resource(pdev, 0);
>> + if (IS_ERR(ddata->regs))
>> + return dev_err_probe(dev, PTR_ERR(ddata->regs),
>> + "Unable to map IO resources\n");
>> +
>> + ddata->clk = devm_clk_get_enabled(dev, NULL);
>> + if (IS_ERR(ddata->clk))
>> + return dev_err_probe(dev, PTR_ERR(ddata->clk),
>> + "Unable to get pwm's clock\n");
>> +
>> + ddata->rst = devm_reset_control_get_optional_exclusive(dev, NULL);
>> + reset_control_deassert(ddata->rst);
>
> You could use devm_add_action_or_reset() to add reset assertion for
> driver removal and the error paths here, allowing to drop
> ocores_pwm_remove() and ...
>
I see. I would use devm_add_action_or_reset(), and drop redundant code.
>> + ddata->clk_rate = clk_get_rate(ddata->clk);
>> + if (ddata->clk_rate <= 0)
>> + return dev_err_probe(dev, ddata->clk_rate,
>> + "Unable to get clock's rate\n");
>
> ... then this wouldn't leave the reset deasserted ...
>
...
>> +
>> + ret = devm_pwmchip_add(dev, chip);
>> + if (ret < 0) {
>> + reset_control_assert(ddata->rst);
>
> ... and this could be dropped.
>
...
>> + clk_disable_unprepare(ddata->clk);
>
> This can be dropped, devm_clk_get_enabled() already disables the clock
> on probe error.
>
Will drop.
>> + return dev_err_probe(dev, ret, "Could not register PWM chip\n");
>> + }
>> +
>> + platform_set_drvdata(pdev, ddata);
>> +
>> + return ret;
>> +}
>> +
>> +static void ocores_pwm_remove(struct platform_device *dev)
>> +{
>> + struct ocores_pwm_device *ddata = platform_get_drvdata(dev);
>> +
>> + reset_control_assert(ddata->rst);
>> + clk_disable_unprepare(ddata->clk);
>
> Drop as well, devm_clk_get_enabled() already disables the clock on
> driver removal.
>
I will drop all remove() interface.
Thank you for taking time to review this patchset.
Best Regards,
William
> regards
> Philipp
@@ -16206,6 +16206,13 @@ 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@starfivetech.com>
+M: Hal Feng <hal.feng@starfivetech.com>
+S: Supported
+F: Documentation/devicetree/bindings/pwm/opencores,pwm.yaml
+F: drivers/pwm/pwm-ocores.c
+
OPENRISC ARCHITECTURE
M: Jonas Bonn <jonas@southpole.se>
M: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
@@ -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
@@ -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
new file mode 100644
@@ -0,0 +1,232 @@
+// 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>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+
+/* OCPWM_CTRL register bits*/
+#define REG_OCPWM_EN BIT(0)
+#define REG_OCPWM_ECLK BIT(1)
+#define REG_OCPWM_NEC BIT(2)
+#define REG_OCPWM_OE BIT(3)
+#define REG_OCPWM_SIGNLE BIT(4)
+#define REG_OCPWM_INTE BIT(5)
+#define REG_OCPWM_INT BIT(6)
+#define REG_OCPWM_CNTRRST BIT(7)
+#define REG_OCPWM_CAPTE BIT(8)
+
+struct ocores_pwm_device {
+ struct pwm_chip chip;
+ struct clk *clk;
+ struct reset_control *rst;
+ const struct ocores_pwm_data *data;
+ void __iomem *regs;
+ u32 clk_rate; /* PWM APB clock frequency */
+};
+
+struct ocores_pwm_data {
+ void __iomem *(*get_ch_base)(void __iomem *base, unsigned int channel);
+};
+
+static inline u32 ocores_readl(struct ocores_pwm_device *ddata,
+ unsigned int channel,
+ unsigned int offset)
+{
+ void __iomem *base = ddata->data->get_ch_base ?
+ ddata->data->get_ch_base(ddata->regs, channel) : ddata->regs;
+
+ return readl(base + offset);
+}
+
+static inline void ocores_writel(struct ocores_pwm_device *ddata,
+ unsigned int channel,
+ unsigned int offset, u32 val)
+{
+ void __iomem *base = ddata->data->get_ch_base ?
+ ddata->data->get_ch_base(ddata->regs, channel) : ddata->regs;
+
+ writel(val, base + offset);
+}
+
+static inline struct ocores_pwm_device *chip_to_ocores(struct pwm_chip *chip)
+{
+ return container_of(chip, struct ocores_pwm_device, chip);
+}
+
+static void __iomem *starfive_jh71x0_get_ch_base(void __iomem *base,
+ unsigned int channel)
+{
+ unsigned int offset = (channel > 3 ? 1 << 15 : 0) + (channel & 3) * 0x10;
+
+ return base + offset;
+}
+
+static int ocores_pwm_get_state(struct pwm_chip *chip,
+ struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct ocores_pwm_device *ddata = chip_to_ocores(chip);
+ u32 period_data, duty_data, ctrl_data;
+
+ period_data = ocores_readl(ddata, pwm->hwpwm, 0x8);
+ duty_data = ocores_readl(ddata, pwm->hwpwm, 0x4);
+ ctrl_data = ocores_readl(ddata, pwm->hwpwm, 0xC);
+
+ state->period = DIV_ROUND_UP_ULL((u64)period_data * NSEC_PER_SEC, ddata->clk_rate);
+ state->duty_cycle = DIV_ROUND_UP_ULL((u64)duty_data * NSEC_PER_SEC, ddata->clk_rate);
+ state->polarity = PWM_POLARITY_INVERSED;
+ state->enabled = (ctrl_data & REG_OCPWM_EN) ? true : false;
+
+ return 0;
+}
+
+static int ocores_pwm_apply(struct pwm_chip *chip,
+ struct pwm_device *pwm,
+ const struct pwm_state *state)
+{
+ struct ocores_pwm_device *ddata = chip_to_ocores(chip);
+ u32 ctrl_data = 0;
+ u64 period_data, duty_data;
+
+ if (state->polarity != PWM_POLARITY_INVERSED)
+ return -EINVAL;
+
+ ctrl_data = ocores_readl(ddata, pwm->hwpwm, 0xC);
+ ocores_writel(ddata, pwm->hwpwm, 0xC, 0);
+
+ period_data = DIV_ROUND_DOWN_ULL(state->period * ddata->clk_rate, NSEC_PER_SEC);
+ if (period_data <= U32_MAX)
+ ocores_writel(ddata, pwm->hwpwm, 0x8, (u32)period_data);
+ else
+ return -EINVAL;
+
+ duty_data = DIV_ROUND_DOWN_ULL(state->duty_cycle * ddata->clk_rate, NSEC_PER_SEC);
+ if (duty_data <= U32_MAX)
+ ocores_writel(ddata, pwm->hwpwm, 0x4, (u32)duty_data);
+ else
+ return -EINVAL;
+
+ ocores_writel(ddata, pwm->hwpwm, 0xC, 0);
+
+ if (state->enabled) {
+ ctrl_data = ocores_readl(ddata, pwm->hwpwm, 0xC);
+ ocores_writel(ddata, pwm->hwpwm, 0xC, ctrl_data | REG_OCPWM_EN | REG_OCPWM_OE);
+ }
+
+ return 0;
+}
+
+static const struct pwm_ops ocores_pwm_ops = {
+ .get_state = ocores_pwm_get_state,
+ .apply = ocores_pwm_apply,
+};
+
+static const struct ocores_pwm_data jh7100_pwm_data = {
+ .get_ch_base = starfive_jh71x0_get_ch_base,
+};
+
+static const struct ocores_pwm_data jh7110_pwm_data = {
+ .get_ch_base = starfive_jh71x0_get_ch_base,
+};
+
+static const struct of_device_id ocores_pwm_of_match[] = {
+ { .compatible = "opencores,pwm-v1" },
+ { .compatible = "starfive,jh7100-pwm", .data = &jh7100_pwm_data},
+ { .compatible = "starfive,jh7110-pwm", .data = &jh7110_pwm_data},
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, ocores_pwm_of_match);
+
+static int ocores_pwm_probe(struct platform_device *pdev)
+{
+ const struct of_device_id *id;
+ struct device *dev = &pdev->dev;
+ struct ocores_pwm_device *ddata;
+ struct pwm_chip *chip;
+ int ret;
+
+ id = of_match_device(ocores_pwm_of_match, dev);
+ if (!id)
+ return -EINVAL;
+
+ ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
+ if (!ddata)
+ return -ENOMEM;
+
+ ddata->data = id->data;
+ chip = &ddata->chip;
+ chip->dev = dev;
+ chip->ops = &ocores_pwm_ops;
+ chip->npwm = 8;
+ chip->of_pwm_n_cells = 3;
+
+ ddata->regs = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(ddata->regs))
+ return dev_err_probe(dev, PTR_ERR(ddata->regs),
+ "Unable to map IO resources\n");
+
+ ddata->clk = devm_clk_get_enabled(dev, NULL);
+ if (IS_ERR(ddata->clk))
+ return dev_err_probe(dev, PTR_ERR(ddata->clk),
+ "Unable to get pwm's clock\n");
+
+ ddata->rst = devm_reset_control_get_optional_exclusive(dev, NULL);
+ reset_control_deassert(ddata->rst);
+
+ ddata->clk_rate = clk_get_rate(ddata->clk);
+ if (ddata->clk_rate <= 0)
+ return dev_err_probe(dev, ddata->clk_rate,
+ "Unable to get clock's rate\n");
+
+ ret = devm_pwmchip_add(dev, chip);
+ if (ret < 0) {
+ reset_control_assert(ddata->rst);
+ clk_disable_unprepare(ddata->clk);
+ return dev_err_probe(dev, ret, "Could not register PWM chip\n");
+ }
+
+ platform_set_drvdata(pdev, ddata);
+
+ return ret;
+}
+
+static void ocores_pwm_remove(struct platform_device *dev)
+{
+ struct ocores_pwm_device *ddata = platform_get_drvdata(dev);
+
+ reset_control_assert(ddata->rst);
+ clk_disable_unprepare(ddata->clk);
+}
+
+static struct platform_driver ocores_pwm_driver = {
+ .probe = ocores_pwm_probe,
+ .remove_new = ocores_pwm_remove,
+ .driver = {
+ .name = "ocores-pwm",
+ .of_match_table = ocores_pwm_of_match,
+ },
+};
+module_platform_driver(ocores_pwm_driver);
+
+MODULE_AUTHOR("Jieqin Chen");
+MODULE_AUTHOR("Hal Feng <hal.feng@starfivetech.com>");
+MODULE_DESCRIPTION("OpenCores PWM PTC driver");
+MODULE_LICENSE("GPL");