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@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 ... > 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
