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@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 | 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@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..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
