From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751805AbdBOOpo (ORCPT ); Wed, 15 Feb 2017 09:45:44 -0500 Received: from mail-pf0-f193.google.com ([209.85.192.193]:35479 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751175AbdBOOpm (ORCPT ); Wed, 15 Feb 2017 09:45:42 -0500 Date: Wed, 15 Feb 2017 22:45:31 +0800 From: Yang Ling To: Marcin Nowakowski , Thierry Reding , Keguang Zhang Cc: linux-kernel@vger.kernel.org, linux-pwm@vger.kernel.org, linux-mips@linux-mips.org, Yang Ling Subject: [PATCH v2 1/2] pwm: loongson1: Add PWM driver for Loongson1 SoC Message-ID: <20170215144531.GA39000@ubuntu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add support for the PWM controller present in Loongson1 family of SoCs. Signed-off-by: Yang Ling --- V2: Remove ls1x_pwm_channel. Remove period_ns/duty_ns check. Add return values check. --- drivers/pwm/Kconfig | 9 +++ drivers/pwm/Makefile | 1 + drivers/pwm/pwm-loongson1.c | 148 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 158 insertions(+) create mode 100644 drivers/pwm/pwm-loongson1.c diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index f92dd41..985f2fe 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -216,6 +216,15 @@ config PWM_JZ4740 To compile this driver as a module, choose M here: the module will be called pwm-jz4740. +config PWM_LOONGSON1 + tristate "Loongson1 PWM support" + depends on MACH_LOONGSON32 + help + Generic PWM framework driver for Loongson1 based machines. + + To compile this driver as a module, choose M here: the module + will be called pwm-loongson1. + config PWM_LP3943 tristate "TI/National Semiconductor LP3943 PWM support" depends on MFD_LP3943 diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index a48bdb5..1979453 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -19,6 +19,7 @@ obj-$(CONFIG_PWM_HIBVT) += pwm-hibvt.o obj-$(CONFIG_PWM_IMG) += pwm-img.o obj-$(CONFIG_PWM_IMX) += pwm-imx.o obj-$(CONFIG_PWM_JZ4740) += pwm-jz4740.o +obj-$(CONFIG_PWM_LOONGSON1) += pwm-loongson1.o obj-$(CONFIG_PWM_LP3943) += pwm-lp3943.o obj-$(CONFIG_PWM_LPC18XX_SCT) += pwm-lpc18xx-sct.o obj-$(CONFIG_PWM_LPC32XX) += pwm-lpc32xx.o diff --git a/drivers/pwm/pwm-loongson1.c b/drivers/pwm/pwm-loongson1.c new file mode 100644 index 0000000..6c2d06d --- /dev/null +++ b/drivers/pwm/pwm-loongson1.c @@ -0,0 +1,148 @@ +/* + * Copyright (c) 2017 Yang Ling + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#include +#include +#include +#include +#include + +struct ls1x_pwm_chip { + struct clk *clk; + void __iomem *base; + struct pwm_chip chip; +}; + +static inline struct ls1x_pwm_chip *to_ls1x_pwm_chip(struct pwm_chip *chip) +{ + return container_of(chip, struct ls1x_pwm_chip, chip); +} + +static int ls1x_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, + int duty_ns, int period_ns) +{ + unsigned long long tmp; + unsigned long period_cnt, duty_cnt; + struct ls1x_pwm_chip *pc = to_ls1x_pwm_chip(chip); + + tmp = (unsigned long long)clk_get_rate(pc->clk) * period_ns; + do_div(tmp, 1000000000); + period_cnt = tmp; + + tmp = (unsigned long long)period_cnt * duty_ns; + do_div(tmp, period_ns); + duty_cnt = period_cnt - tmp; + + if (duty_cnt >= period_cnt) + duty_cnt = period_cnt - 1; + + if (duty_cnt >> 24 || period_cnt >> 24) + return -EINVAL; + + writel(duty_cnt, pc->base + PWM_HRC(pwm->hwpwm)); + writel(period_cnt, pc->base + PWM_LRC(pwm->hwpwm)); + writel(0, pc->base + PWM_CNT(pwm->hwpwm)); + + return 0; +} + +static int ls1x_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct ls1x_pwm_chip *pc = to_ls1x_pwm_chip(chip); + + writel(CNT_RST, pc->base + PWM_CTRL(pwm->hwpwm)); + writel(CNT_EN, pc->base + PWM_CTRL(pwm->hwpwm)); + + return 0; +} + +static void ls1x_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct ls1x_pwm_chip *pc = to_ls1x_pwm_chip(chip); + + writel(PWM_OE, pc->base + PWM_CTRL(pwm->hwpwm)); +} + +static const struct pwm_ops ls1x_pwm_ops = { + .config = ls1x_pwm_config, + .enable = ls1x_pwm_enable, + .disable = ls1x_pwm_disable, + .owner = THIS_MODULE, +}; + +static int ls1x_pwm_probe(struct platform_device *pdev) +{ + int ret; + struct ls1x_pwm_chip *pc = NULL; + struct resource *res = NULL; + + pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL); + if (!pc) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + pc->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(pc->base)) + return PTR_ERR(pc->base); + + pc->clk = devm_clk_get(&pdev->dev, "ls1x-pwmtimer"); + if (IS_ERR(pc->clk)) { + dev_err(&pdev->dev, "failed to get %s clock\n", pdev->name); + return PTR_ERR(pc->clk); + } + + ret = clk_prepare_enable(pc->clk); + if (ret < 0) { + dev_err(&pdev->dev, "failed to enable clock: %d\n", ret); + return ret; + } + + pc->chip.ops = &ls1x_pwm_ops; + pc->chip.dev = &pdev->dev; + pc->chip.base = -1; + pc->chip.npwm = 4; + + platform_set_drvdata(pdev, pc); + + ret = pwmchip_add(&pc->chip); + if (ret < 0) { + dev_err(&pdev->dev, "failed to add PWM chip: %d\n", ret); + clk_disable_unprepare(pc->clk); + } + + return ret; +} + +static int ls1x_pwm_remove(struct platform_device *pdev) +{ + struct ls1x_pwm_chip *pc = platform_get_drvdata(pdev); + int ret; + + ret = pwmchip_remove(&pc->chip); + if (ret < 0) + return ret; + + clk_disable_unprepare(pc->clk); + + return 0; +} + +static struct platform_driver ls1x_pwm_driver = { + .driver = { + .name = "ls1x-pwm", + }, + .probe = ls1x_pwm_probe, + .remove = ls1x_pwm_remove, +}; +module_platform_driver(ls1x_pwm_driver); + +MODULE_AUTHOR("Yang Ling "); +MODULE_DESCRIPTION("Loongson1 PWM driver"); +MODULE_ALIAS("platform:loongson1-pwm"); +MODULE_LICENSE("GPL"); -- 1.9.1