[v9,2/4] pwm: opencores: Add PWM driver support

Message ID	20231208094209.1910934-3-william.qiu@starfivetech.com
State	Changes Requested
Headers	show Return-Path: <linux-pwm+bounces-452-incoming=patchwork.ozlabs.org@vger.kernel.org> From: William Qiu <william.qiu@starfivetech.com> To: <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>, <linux-riscv@lists.infradead.org>, <linux-pwm@vger.kernel.org> CC: Emil Renner Berthing <kernel@esmil.dk>, Rob Herring <robh+dt@kernel.org>, Thierry Reding <thierry.reding@gmail.com>, Philipp Zabel <p.zabel@pengutronix.de>, Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>, Conor Dooley <conor+dt@kernel.org>, =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= <u.kleine-koenig@pengutronix.de>, "Hal Feng" <hal.feng@starfivetech.com>, Paul Walmsley <paul.walmsley@sifive.com>, Palmer Dabbelt <palmer@dabbelt.com>, Albert Ou <aou@eecs.berkeley.edu>, William Qiu <william.qiu@starfivetech.com> Subject: [PATCH v9 2/4] pwm: opencores: Add PWM driver support Date: Fri, 8 Dec 2023 17:42:07 +0800 Message-ID: <20231208094209.1910934-3-william.qiu@starfivetech.com> In-Reply-To: <20231208094209.1910934-1-william.qiu@starfivetech.com> References: <20231208094209.1910934-1-william.qiu@starfivetech.com> Precedence: bulk MIME-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: quoted-printable
Series	StarFive's Pulse Width Modulation driver support \| expand [v9,0/4] StarFive's Pulse Width Modulation driver support [v9,1/4] dt-bindings: pwm: Add bindings for OpenCores PWM Controller [v9,2/4] pwm: opencores: Add PWM driver support [v9,3/4] riscv: dts: starfive: jh7100: Add PWM node and pins configuration [v9,4/4] riscv: dts: starfive: jh7110: Add PWM node and pins configuration

diff --git a/MAINTAINERS b/MAINTAINERS index 788be9ab5b73..7a11a22da09e 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -16204,6 +16204,13 @@ 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@starfivetech.com> +M: Hal Feng <hal.feng@starfivetech.com> +S: Supported +F: Documentation/devicetree/bindings/pwm/opencores,pwm.yaml +F: drivers/pwm/pwm-ocores.c + OPENRISC ARCHITECTURE M: Jonas Bonn <jonas@southpole.se> M: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> 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..996ca3805901 --- /dev/null +++ b/drivers/pwm/pwm-ocores.c @@ -0,0 +1,229 @@ +// 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 void ocores_reset_control_assert(void *data) +{ + reset_control_assert(data); +} + +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); + + ret = devm_add_action_or_reset(dev, ocores_reset_control_assert, ddata->rst); + if (ret) + return ret; + + 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"); + + ret = devm_pwmchip_add(dev, chip); + if (ret < 0) + return dev_err_probe(dev, ret, "Could not register PWM chip\n"); + + platform_set_drvdata(pdev, ddata); + + return ret; +} + +static struct platform_driver ocores_pwm_driver = { + .probe = ocores_pwm_probe, + .driver = { + .name = "ocores-pwm", + .of_match_table = ocores_pwm_of_match, + }, +}; +module_platform_driver(ocores_pwm_driver); + +MODULE_AUTHOR("Jieqin Chen"); +MODULE_AUTHOR("Hal Feng <hal.feng@starfivetech.com>"); +MODULE_DESCRIPTION("OpenCores PWM PTC driver"); +MODULE_LICENSE("GPL");

[v9,2/4] pwm: opencores: Add PWM driver support

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