From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 330D9CED27C for ; Tue, 8 Oct 2024 08:39:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=/SSSVXjXk6AXJlKFnRauBChGgrHIidrVLlgRA+FmoU0=; b=mfiv6m7qe9IPAR /M/tviIGAOAApZkIGIHx+ksFYEWfNedbwttgAejk/PHdOYtKo3k/K4YFkXXrfg6Nnryj17uZQhmi4 PSeDQp4hgF3t4FGHPEX3CFw/AFO8JzgZp4gUmTGmuUyHUlEBYeY00lVvR6bEvUUFi9bm3k7KJILHH 7gFb4BjcT1IvRO+LsQbCdrv8CnNOjNByrB/WigzTLCSbbVJWzqMiM4plpuPCAB2GJ/67JnIKIiV0e UAu0FcYykVHRwPO8ds1D2JyPW6QvgbJGzrU2fGBa89Njq5++Oyyj1oYQxBBE0nXct19ze/hw1t0Pk pmcusigeHtnGL60dYssg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1sy5kv-000000055g5-2T39; Tue, 08 Oct 2024 08:39:45 +0000 Received: from gofer.mess.org ([88.97.38.141]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1sy5WU-0000000512V-2ZR8 for linux-riscv@lists.infradead.org; Tue, 08 Oct 2024 08:24:52 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=mess.org; s=2020; t=1728375885; bh=p8O/sEYZVbUMhVZQJSEP2Q1Ny12LP28b8VlON+FkH54=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=B4dTXIaI6Bnt8yB3TnEYNb+az8JLv5lvmWJWGjc/PndukWyuiXbT9Tlz9E15MOno+ Jat56Qrgcnp7/9QHOYWs0XxBOri4ClVwyX21PQoRbSKiZBNwdPJp486SzvcMgGbKah HEoHAQ2tHIc2ahMaJXIZ4r2rJKTygL3eZgaPEW189J37JQwN03ZbelxqmuomDBxqD2 80qpZ5CrfNEAzRjY6XMB2407NhusmJxUX5Kbx7TqFhgK7TttLa3bU9zuv5D3hk3Jm/ 1eeAGoF6kQbZIYIFKqvAx4R2CD8Fg42Fk+EThx1l24gLu/pK13701yAmaRlr0LsXNu j3pVd79uFS35g== Received: by gofer.mess.org (Postfix, from userid 1000) id 6C2DC1002BF; Tue, 8 Oct 2024 09:24:45 +0100 (BST) Date: Tue, 8 Oct 2024 09:24:45 +0100 From: Sean Young To: Chen Wang Cc: ukleinek@kernel.org, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, unicorn_wang@outlook.com, inochiama@outlook.com, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pwm@vger.kernel.org, linux-riscv@lists.infradead.org, chao.wei@sophgo.com, haijiao.liu@sophgo.com, xiaoguang.xing@sophgo.com, chunzhi.lin@sophgo.com Subject: Re: [PATCH v3 2/3] pwm: sophgo: add driver for Sophgo SG2042 PWM Message-ID: References: <57cf7ac3b4c092df1a6962d310b6d2603ca26995.1728355974.git.unicorn_wang@outlook.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <57cf7ac3b4c092df1a6962d310b6d2603ca26995.1728355974.git.unicorn_wang@outlook.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241008_012451_298530_A49B3EA1 X-CRM114-Status: GOOD ( 34.13 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On Tue, Oct 08, 2024 at 11:04:14AM +0800, Chen Wang wrote: > From: Chen Wang > > Add a PWM driver for PWM controller in Sophgo SG2042 SoC. > > Signed-off-by: Chen Wang > --- > 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 > + * > + * 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 > +#include > +#include > +#include > +#include > +#include > + > +#include > + > +/* > + * 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 > _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv