| Message ID | cover.1725931796.git.unicorn_wang@outlook.com |
|---|---|
| Headers | show |
| Series | pwm: Add pwm driver for Sophgo SG2042 | expand |
Ping ~ hi, Uwe, Can you please review and comment? Thanks, Chen On 2024/9/10 10:08, Chen Wang wrote: > From: Chen Wang <unicorn_wang@outlook.com> > > Add a PWM driver for PWM controller in Sophgo SG2042 SoC. > > Signed-off-by: Chen Wang <unicorn_wang@outlook.com> > --- > drivers/pwm/Kconfig | 10 ++ > drivers/pwm/Makefile | 1 + > drivers/pwm/pwm-sophgo-sg2042.c | 180 ++++++++++++++++++++++++++++++++ > 3 files changed, 191 insertions(+) > create mode 100644 drivers/pwm/pwm-sophgo-sg2042.c > > diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig > index 3e53838990f5..de8a36ecabbb 100644 > --- a/drivers/pwm/Kconfig > +++ b/drivers/pwm/Kconfig > @@ -577,6 +577,16 @@ config PWM_SL28CPLD > To compile this driver as a module, choose M here: the module > will be called pwm-sl28cpld. > > +config PWM_SOPHGO_SG2042 > + tristate "Sophgo SG2042 PWM support" > + depends on ARCH_SOPHGO || COMPILE_TEST > + help > + PWM driver for the PWM controller on Sophgo SG2042 SoC. The PWM > + controller supports outputing 4 channels of PWM waveforms. > + > + To compile this driver as a module, choose M here: the module > + will be called pwm_sophgo_sg2042. > + > config PWM_SPEAR > tristate "STMicroelectronics SPEAr PWM support" > depends on PLAT_SPEAR || COMPILE_TEST > diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile > index 0be4f3e6dd43..ef2555e83183 100644 > --- a/drivers/pwm/Makefile > +++ b/drivers/pwm/Makefile > @@ -52,6 +52,7 @@ obj-$(CONFIG_PWM_RZ_MTU3) += pwm-rz-mtu3.o > obj-$(CONFIG_PWM_SAMSUNG) += pwm-samsung.o > obj-$(CONFIG_PWM_SIFIVE) += pwm-sifive.o > obj-$(CONFIG_PWM_SL28CPLD) += pwm-sl28cpld.o > +obj-$(CONFIG_PWM_SOPHGO_SG2042) += pwm-sophgo-sg2042.o > obj-$(CONFIG_PWM_SPEAR) += pwm-spear.o > obj-$(CONFIG_PWM_SPRD) += pwm-sprd.o > obj-$(CONFIG_PWM_STI) += pwm-sti.o > diff --git a/drivers/pwm/pwm-sophgo-sg2042.c b/drivers/pwm/pwm-sophgo-sg2042.c > new file mode 100644 > index 000000000000..198019b751ad > --- /dev/null > +++ b/drivers/pwm/pwm-sophgo-sg2042.c > @@ -0,0 +1,180 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Sophgo SG2042 PWM Controller Driver > + * > + * Copyright (C) 2024 Sophgo Technology Inc. > + * Copyright (C) 2024 Chen Wang <unicorn_wang@outlook.com> > + * > + * Limitations: > + * - After reset, the output of the PWM channel is always high. > + * The value of HLPERIOD/PERIOD is 0. > + * - When HLPERIOD or PERIOD is reconfigured, PWM will start to > + * output waveforms with the new configuration after completing > + * the running period. > + * - When PERIOD and HLPERIOD is set to 0, the PWM wave output will > + * be stopped and the output is pulled to high. > + */ > + > +#include <linux/clk.h> > +#include <linux/err.h> > +#include <linux/io.h> > +#include <linux/module.h> > +#include <linux/platform_device.h> > +#include <linux/pwm.h> > + > +#include <asm/div64.h> > + > +/* > + * Offset RegisterName > + * 0x0000 HLPERIOD0 > + * 0x0004 PERIOD0 > + * 0x0008 HLPERIOD1 > + * 0x000C PERIOD1 > + * 0x0010 HLPERIOD2 > + * 0x0014 PERIOD2 > + * 0x0018 HLPERIOD3 > + * 0x001C PERIOD3 > + * Four groups and every group is composed of HLPERIOD & PERIOD > + */ > +#define SG2042_HLPERIOD(chan) ((chan) * 8 + 0) > +#define SG2042_PERIOD(chan) ((chan) * 8 + 4) > + > +#define SG2042_PWM_CHANNELNUM 4 > + > +/** > + * struct sg2042_pwm_ddata - private driver data > + * @base: base address of mapped PWM registers > + * @clk_rate_hz: rate of base clock in HZ > + */ > +struct sg2042_pwm_ddata { > + void __iomem *base; > + unsigned long clk_rate_hz; > +}; > + > +static void pwm_sg2042_config(void __iomem *base, unsigned int chan, u32 period, u32 hlperiod) > +{ > + writel(period, base + SG2042_PERIOD(chan)); > + writel(hlperiod, base + SG2042_HLPERIOD(chan)); > +} > + > +static int pwm_sg2042_apply(struct pwm_chip *chip, struct pwm_device *pwm, > + const struct pwm_state *state) > +{ > + struct sg2042_pwm_ddata *ddata = pwmchip_get_drvdata(chip); > + u32 hlperiod; > + u32 period; > + > + if (state->polarity == PWM_POLARITY_INVERSED) > + return -EINVAL; > + > + if (!state->enabled) { > + pwm_sg2042_config(ddata->base, pwm->hwpwm, 0, 0); > + return 0; > + } > + > + /* > + * Period of High level (duty_cycle) = HLPERIOD x Period_clk > + * Period of One Cycle (period) = PERIOD x Period_clk > + */ > + period = min(mul_u64_u64_div_u64(ddata->clk_rate_hz, state->period, NSEC_PER_SEC), U32_MAX); > + hlperiod = min(mul_u64_u64_div_u64(ddata->clk_rate_hz, state->duty_cycle, NSEC_PER_SEC), U32_MAX); > + > + if (hlperiod > period) { > + dev_err(pwmchip_parent(chip), "period < hlperiod, failed to apply current setting\n"); > + return -EINVAL; > + } > + > + dev_dbg(pwmchip_parent(chip), "chan[%u]: period=%u, hlperiod=%u\n", > + pwm->hwpwm, period, hlperiod); > + > + pwm_sg2042_config(ddata->base, pwm->hwpwm, period, hlperiod); > + > + return 0; > +} > + > +static int pwm_sg2042_get_state(struct pwm_chip *chip, struct pwm_device *pwm, > + struct pwm_state *state) > +{ > + struct sg2042_pwm_ddata *ddata = pwmchip_get_drvdata(chip); > + unsigned int chan = pwm->hwpwm; > + u32 hlperiod; > + u32 period; > + > + period = readl(ddata->base + SG2042_PERIOD(chan)); > + hlperiod = readl(ddata->base + SG2042_HLPERIOD(chan)); > + > + if (!period && !hlperiod) > + state->enabled = false; > + else > + state->enabled = true; > + > + state->period = DIV_ROUND_UP_ULL((u64)period * NSEC_PER_SEC, ddata->clk_rate_hz); > + state->duty_cycle = DIV_ROUND_UP_ULL((u64)hlperiod * NSEC_PER_SEC, ddata->clk_rate_hz); > + > + state->polarity = PWM_POLARITY_NORMAL; > + > + return 0; > +} > + > +static const struct pwm_ops pwm_sg2042_ops = { > + .apply = pwm_sg2042_apply, > + .get_state = pwm_sg2042_get_state, > +}; > + > +static const struct of_device_id sg2042_pwm_ids[] = { > + { .compatible = "sophgo,sg2042-pwm" }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, sg2042_pwm_ids); > + > +static int pwm_sg2042_probe(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct sg2042_pwm_ddata *ddata; > + struct pwm_chip *chip; > + struct clk *clk; > + int ret; > + > + chip = devm_pwmchip_alloc(dev, SG2042_PWM_CHANNELNUM, sizeof(*ddata)); > + if (IS_ERR(chip)) > + return PTR_ERR(chip); > + ddata = pwmchip_get_drvdata(chip); > + > + ddata->base = devm_platform_ioremap_resource(pdev, 0); > + if (IS_ERR(ddata->base)) > + return PTR_ERR(ddata->base); > + > + clk = devm_clk_get_enabled(dev, "apb"); > + if (IS_ERR(clk)) > + return dev_err_probe(dev, PTR_ERR(clk), "failed to get base clk\n"); > + > + ret = devm_clk_rate_exclusive_get(dev, clk); > + if (ret) > + return dev_err_probe(dev, ret, "failed to get exclusive rate\n"); > + > + ddata->clk_rate_hz = clk_get_rate(clk); > + if (!ddata->clk_rate_hz || ddata->clk_rate_hz > NSEC_PER_SEC) > + return dev_err_probe(dev, -EINVAL, > + "Invalid clock rate: %lu\n", ddata->clk_rate_hz); > + > + chip->ops = &pwm_sg2042_ops; > + > + ret = devm_pwmchip_add(dev, chip); > + if (ret < 0) > + return dev_err_probe(dev, ret, "failed to register PWM chip\n"); > + > + return 0; > +} > + > +static struct platform_driver pwm_sg2042_driver = { > + .driver = { > + .name = "sg2042-pwm", > + .of_match_table = sg2042_pwm_ids, > + }, > + .probe = pwm_sg2042_probe, > +}; > +module_platform_driver(pwm_sg2042_driver); > + > +MODULE_AUTHOR("Chen Wang"); > +MODULE_DESCRIPTION("Sophgo SG2042 PWM driver"); > +MODULE_LICENSE("GPL");
From: Chen Wang <unicorn_wang@outlook.com> Add driver for pwm controller of Sophgo SG2042 SoC. Thanks, Chen --- Changes in v2: The patch series is based on v6.11-rc6. Fixed following issues as per comments from Yixun Lan, Krzysztof Kozlowski and Uwe Kleine-König, thanks. - Some minor issues in dt-bindings. - driver issues, use macros with name prefix for registers access; add limitations comments; fixed potential calculation overflow problem; add .get_state() callback and other miscellaneous code improvements. Changes in v1: The patch series is based on v6.11-rc6. You can simply review or test the patches at the link [1]. Link: https://lore.kernel.org/linux-riscv/cover.1725536870.git.unicorn_wang@outlook.com/ [1] --- Chen Wang (2): dt-bindings: pwm: sophgo: add PWM controller for SG2042 pwm: sophgo: add driver for Sophgo SG2042 PWM .../bindings/pwm/sophgo,sg2042-pwm.yaml | 51 +++++ drivers/pwm/Kconfig | 10 + drivers/pwm/Makefile | 1 + drivers/pwm/pwm-sophgo-sg2042.c | 180 ++++++++++++++++++ 4 files changed, 242 insertions(+) create mode 100644 Documentation/devicetree/bindings/pwm/sophgo,sg2042-pwm.yaml create mode 100644 drivers/pwm/pwm-sophgo-sg2042.c base-commit: 431c1646e1f86b949fa3685efc50b660a364c2b6