| Message ID | 57cf7ac3b4c092df1a6962d310b6d2603ca26995.1728355974.git.unicorn_wang@outlook.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | pwm: Add pwm driver for Sophgo SG2042 | expand |
On Tue, Oct 08, 2024 at 11:04:14AM +0800, 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 0915c1e7df16..ec85f3895936 100644 > --- a/drivers/pwm/Kconfig > +++ b/drivers/pwm/Kconfig > @@ -584,6 +584,16 @@ 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 9081e0c0e9e0..539e0def3f82 100644 > --- a/drivers/pwm/Makefile > +++ b/drivers/pwm/Makefile > @@ -53,6 +53,7 @@ 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; I think you can add here: chip->atomic = true; As far as I can see, the driver does not do any sleeping operations in pwm_sg2042_apply(). This probably should be tested with CONFIG_PWM_DEBUG and CONFIG_DEBUG_ATOMIC_SLEEP just to be sure. Thanks, Sean > + > + 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"); > -- > 2.34.1 >
On 2024/10/8 16:24, Sean Young wrote: > On Tue, Oct 08, 2024 at 11:04:14AM +0800, Chen Wang wrote: >> From: Chen Wang <unicorn_wang@outlook.com> >> >> Add a PWM driver for PWM controller in Sophgo SG2042 SoC. [......] >> +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; > I think you can add here: > > chip->atomic = true; > > As far as I can see, the driver does not do any sleeping operations > in pwm_sg2042_apply(). This probably should be tested with > CONFIG_PWM_DEBUG and CONFIG_DEBUG_ATOMIC_SLEEP just to be sure. > > Thanks, > Sean Thank you Sean. We don't sleep when apply, so atomic should be needed. [......]
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 0915c1e7df16..ec85f3895936 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -584,6 +584,16 @@ 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 9081e0c0e9e0..539e0def3f82 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -53,6 +53,7 @@ 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");