This commit adds a generic PWM framework driver for Nuvoton MA35D1 PWM controller. Signed-off-by: Chi-Wen Weng <cwweng.linux@xxxxxxxxx> --- drivers/pwm/Kconfig | 9 +++ drivers/pwm/Makefile | 1 + drivers/pwm/pwm-ma35d1.c | 169 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 179 insertions(+) create mode 100644 drivers/pwm/pwm-ma35d1.c diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 0915c1e7df16..97b9e83af020 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -411,6 +411,15 @@ config PWM_LPSS_PLATFORM To compile this driver as a module, choose M here: the module will be called pwm-lpss-platform. +config PWM_MA35D1 + tristate "Nuvoton MA35D1 PWM support" + depends on ARCH_MA35 || COMPILE_TEST + help + Generic PWM framework driver for Nuvoton MA35D1. + + To compile this driver as a module, choose M here: the module + will be called pwm-ma35d1. + config PWM_MESON tristate "Amlogic Meson PWM driver" depends on ARCH_MESON || COMPILE_TEST diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index 9081e0c0e9e0..c1d3a1d8add0 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -36,6 +36,7 @@ obj-$(CONFIG_PWM_LPC32XX) += pwm-lpc32xx.o obj-$(CONFIG_PWM_LPSS) += pwm-lpss.o obj-$(CONFIG_PWM_LPSS_PCI) += pwm-lpss-pci.o obj-$(CONFIG_PWM_LPSS_PLATFORM) += pwm-lpss-platform.o +obj-$(CONFIG_PWM_MA35D1) += pwm-ma35d1.o obj-$(CONFIG_PWM_MESON) += pwm-meson.o obj-$(CONFIG_PWM_MEDIATEK) += pwm-mediatek.o obj-$(CONFIG_PWM_MICROCHIP_CORE) += pwm-microchip-core.o diff --git a/drivers/pwm/pwm-ma35d1.c b/drivers/pwm/pwm-ma35d1.c new file mode 100644 index 000000000000..dc2f1f494a91 --- /dev/null +++ b/drivers/pwm/pwm-ma35d1.c @@ -0,0 +1,169 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Driver for the Nuvoton MA35D1 PWM controller + * + * Copyright (C) 2024 Nuvoton Corporation + * Chi-Wen Weng <cwweng@xxxxxxxxxxx> + */ + +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/pwm.h> +#include <linux/io.h> +#include <linux/clk.h> +#include <linux/math64.h> + +/* The following are registers for PWM controller */ +#define REG_PWM_CTL0 (0x00) +#define REG_PWM_CNTEN (0x20) +#define REG_PWM_PERIOD0 (0x30) +#define REG_PWM_CMPDAT0 (0x50) +#define REG_PWM_WGCTL0 (0xB0) +#define REG_PWM_POLCTL (0xD4) +#define REG_PWM_POEN (0xD8) + +#define PWM_TOTAL_CHANNELS 6 +#define PWM_CH_REG_SIZE 4 + +struct nuvoton_pwm { + void __iomem *base; + u64 clkrate; +}; + +static inline struct nuvoton_pwm *to_nuvoton_pwm(struct pwm_chip *chip) +{ + return pwmchip_get_drvdata(chip); +} + +static int nuvoton_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct nuvoton_pwm *nvtpwm; + unsigned int ch = pwm->hwpwm; + + nvtpwm = to_nuvoton_pwm(chip); + if (state->enabled) { + u64 duty_cycles, period_cycles; + + /* Calculate the duty and period cycles */ + duty_cycles = mul_u64_u64_div_u64(nvtpwm->clkrate, + state->duty_cycle, NSEC_PER_SEC); + if (duty_cycles > 0xFFFF) + duty_cycles = 0xFFFF; + + period_cycles = mul_u64_u64_div_u64(nvtpwm->clkrate, + state->period, NSEC_PER_SEC); + if (period_cycles > 0xFFFF) + period_cycles = 0xFFFF; + + /* Write the duty and period cycles to registers */ + writel(duty_cycles, nvtpwm->base + REG_PWM_CMPDAT0 + (ch * PWM_CH_REG_SIZE)); + writel(period_cycles, nvtpwm->base + REG_PWM_PERIOD0 + (ch * PWM_CH_REG_SIZE)); + /* Enable counter */ + writel(readl(nvtpwm->base + REG_PWM_CNTEN) | BIT(ch), + nvtpwm->base + REG_PWM_CNTEN); + /* Enable output */ + writel(readl(nvtpwm->base + REG_PWM_POEN) | BIT(ch), + nvtpwm->base + REG_PWM_POEN); + } else { + /* Disable counter */ + writel(readl(nvtpwm->base + REG_PWM_CNTEN) & ~BIT(ch), + nvtpwm->base + REG_PWM_CNTEN); + /* Disable output */ + writel(readl(nvtpwm->base + REG_PWM_POEN) & ~BIT(ch), + nvtpwm->base + REG_PWM_POEN); + } + + /* Set polarity state to register */ + if (state->polarity == PWM_POLARITY_NORMAL) + writel(readl(nvtpwm->base + REG_PWM_POLCTL) & ~BIT(ch), + nvtpwm->base + REG_PWM_POLCTL); + else + writel(readl(nvtpwm->base + REG_PWM_POLCTL) | BIT(ch), + nvtpwm->base + REG_PWM_POLCTL); + + return 0; +} + +static int nuvoton_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) +{ + struct nuvoton_pwm *nvtpwm; + unsigned int duty_cycles, period_cycles, cnten, outen, polarity; + unsigned int ch = pwm->hwpwm; + + nvtpwm = to_nuvoton_pwm(chip); + + cnten = readl(nvtpwm->base + REG_PWM_CNTEN); + outen = readl(nvtpwm->base + REG_PWM_POEN); + duty_cycles = readl(nvtpwm->base + REG_PWM_CMPDAT0 + (ch * PWM_CH_REG_SIZE)); + period_cycles = readl(nvtpwm->base + REG_PWM_PERIOD0 + (ch * PWM_CH_REG_SIZE)); + polarity = readl(nvtpwm->base + REG_PWM_POLCTL) & BIT(ch); + + state->enabled = (cnten & BIT(ch)) && (outen & BIT(ch)); + state->polarity = polarity ? PWM_POLARITY_INVERSED : PWM_POLARITY_NORMAL; + state->duty_cycle = DIV64_U64_ROUND_UP((u64)duty_cycles * NSEC_PER_SEC, nvtpwm->clkrate); + state->period = DIV64_U64_ROUND_UP((u64)period_cycles * NSEC_PER_SEC, nvtpwm->clkrate); + + return 0; +} + +static const struct pwm_ops nuvoton_pwm_ops = { + .apply = nuvoton_pwm_apply, + .get_state = nuvoton_pwm_get_state, +}; + +static int nuvoton_pwm_probe(struct platform_device *pdev) +{ + struct pwm_chip *chip; + struct nuvoton_pwm *nvtpwm; + struct clk *clk; + int ret; + + chip = devm_pwmchip_alloc(&pdev->dev, PWM_TOTAL_CHANNELS, sizeof(*nvtpwm)); + if (IS_ERR(chip)) + return PTR_ERR(chip); + + nvtpwm = to_nuvoton_pwm(chip); + + nvtpwm->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(nvtpwm->base)) + return PTR_ERR(nvtpwm->base); + + clk = devm_clk_get_enabled(&pdev->dev, NULL); + if (IS_ERR(clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(clk), "unable to get the clock"); + + nvtpwm->clkrate = clk_get_rate(clk); + if (nvtpwm->clkrate > NSEC_PER_SEC) + return dev_err_probe(&pdev->dev, -EINVAL, "pwm clock out of range"); + + chip->ops = &nuvoton_pwm_ops; + + ret = devm_pwmchip_add(&pdev->dev, chip); + if (ret < 0) + return dev_err_probe(&pdev->dev, ret, "unable to add pwm chip"); + + return 0; +} + +static const struct of_device_id nuvoton_pwm_of_match[] = { + { .compatible = "nuvoton,ma35d1-pwm" }, + {} +}; +MODULE_DEVICE_TABLE(of, nuvoton_pwm_of_match); + +static struct platform_driver nuvoton_pwm_driver = { + .probe = nuvoton_pwm_probe, + .driver = { + .name = "nuvoton-pwm", + .of_match_table = nuvoton_pwm_of_match, + }, +}; +module_platform_driver(nuvoton_pwm_driver); + +MODULE_ALIAS("platform:nuvoton-pwm"); +MODULE_AUTHOR("Chi-Wen Weng <cwweng@xxxxxxxxxxx>"); +MODULE_DESCRIPTION("Nuvoton MA35D1 PWM driver"); +MODULE_LICENSE("GPL"); -- 2.25.1