From patchwork Tue Aug 18 05:49:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rahul Tanwar X-Patchwork-Id: 1346652 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-pwm-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4BW0NX0kKkz9sTW for ; Tue, 18 Aug 2020 15:49:31 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726759AbgHRFt2 (ORCPT ); Tue, 18 Aug 2020 01:49:28 -0400 Received: from mga06.intel.com ([134.134.136.31]:23706 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726228AbgHRFtZ (ORCPT ); Tue, 18 Aug 2020 01:49:25 -0400 IronPort-SDR: JQ1k6jVtGJjnRZu7bQKo+QD+Dyy32DZxjmYSpSfGE1o6wMeQEitf3u5p5wVZDCXMs7/tD9ZzKr yukr/iGdL2Nw== X-IronPort-AV: E=McAfee;i="6000,8403,9716"; a="216370357" X-IronPort-AV: E=Sophos;i="5.76,326,1592895600"; d="scan'208";a="216370357" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Aug 2020 22:49:23 -0700 IronPort-SDR: j2XavEsGKAG9CA8YBjft7ZLliZAq6FeLTpuw3avKx60km1GI+73RjyLl0VJ6v24TmeOuEhudtP QyhrW9aBcTPg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.76,326,1592895600"; d="scan'208";a="277957905" Received: from sgsxdev001.isng.intel.com (HELO localhost) ([10.226.88.11]) by fmsmga007.fm.intel.com with ESMTP; 17 Aug 2020 22:49:20 -0700 From: Rahul Tanwar To: u.kleine-koenig@pengutronix.de, linux-pwm@vger.kernel.org, lee.jones@linaro.org Cc: thierry.reding@gmail.com, p.zabel@pengutronix.de, robh+dt@kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, andriy.shevchenko@intel.com, songjun.Wu@intel.com, cheol.yong.kim@intel.com, qi-ming.wu@intel.com, rahul.tanwar.linux@gmail.com, rtanwar@maxlinear.com, Rahul Tanwar Subject: [PATCH v7 2/2] Add PWM fan controller driver for LGM SoC Date: Tue, 18 Aug 2020 13:49:01 +0800 Message-Id: X-Mailer: git-send-email 2.11.0 In-Reply-To: References: In-Reply-To: References: Sender: linux-pwm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pwm@vger.kernel.org Intel Lightning Mountain(LGM) SoC contains a PWM fan controller. This PWM controller does not have any other consumer, it is a dedicated PWM controller for fan attached to the system. Add driver for this PWM fan controller. Signed-off-by: Rahul Tanwar --- drivers/pwm/Kconfig | 11 ++ drivers/pwm/Makefile | 1 + drivers/pwm/pwm-intel-lgm.c | 267 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 279 insertions(+) create mode 100644 drivers/pwm/pwm-intel-lgm.c diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 7dbcf6973d33..f7a832268c79 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -232,6 +232,17 @@ config PWM_IMX_TPM To compile this driver as a module, choose M here: the module will be called pwm-imx-tpm. +config PWM_INTEL_LGM + tristate "Intel LGM PWM support" + depends on OF && HAS_IOMEM + depends on X86 || COMPILE_TEST + select REGMAP_MMIO + help + Generic PWM fan controller driver for LGM SoC. + + To compile this driver as a module, choose M here: the module + will be called pwm-intel-lgm. + config PWM_IQS620A tristate "Azoteq IQS620A PWM support" depends on MFD_IQS62X || COMPILE_TEST diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index 2c2ba0a03557..e9431b151694 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -20,6 +20,7 @@ obj-$(CONFIG_PWM_IMG) += pwm-img.o obj-$(CONFIG_PWM_IMX1) += pwm-imx1.o obj-$(CONFIG_PWM_IMX27) += pwm-imx27.o obj-$(CONFIG_PWM_IMX_TPM) += pwm-imx-tpm.o +obj-$(CONFIG_PWM_INTEL_LGM) += pwm-intel-lgm.o obj-$(CONFIG_PWM_IQS620A) += pwm-iqs620a.o obj-$(CONFIG_PWM_JZ4740) += pwm-jz4740.o obj-$(CONFIG_PWM_LP3943) += pwm-lp3943.o diff --git a/drivers/pwm/pwm-intel-lgm.c b/drivers/pwm/pwm-intel-lgm.c new file mode 100644 index 000000000000..7f26a30c70f1 --- /dev/null +++ b/drivers/pwm/pwm-intel-lgm.c @@ -0,0 +1,267 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020 Intel Corporation. + * + * Limitations: + * - The hardware supports fixed period which is dependent on 2/3 or 4 + * wire fan mode. + * - Supports normal polarity. Does not support changing polarity. + * - When PWM is disabled, output of PWM will become 0(inactive). It doesn't + * keep track of running period. + * - When duty cycle is changed, PWM output may be a mix of previous setting + * and new setting for the first period. From second period, the output is + * based on new setting. + * - It is a dedicated PWM fan controller. There are no other consumers for + * this PWM controller. + */ +#include +#include +#include +#include +#include +#include +#include + +#define LGM_PWM_FAN_CON0 0x0 +#define LGM_PWM_FAN_EN_EN BIT(0) +#define LGM_PWM_FAN_EN_DIS 0x0 +#define LGM_PWM_FAN_EN_MSK BIT(0) +#define LGM_PWM_FAN_MODE_2WIRE 0x0 +#define LGM_PWM_FAN_MODE_4WIRE 0x1 +#define LGM_PWM_FAN_MODE_MSK BIT(1) +#define LGM_PWM_FAN_DC_MSK GENMASK(23, 16) + +#define LGM_PWM_FAN_CON1 0x4 +#define LGM_PWM_FAN_MAX_RPM_MSK GENMASK(15, 0) + +#define LGM_PWM_MAX_RPM (BIT(16) - 1) +#define LGM_PWM_DEFAULT_RPM 4000 +#define LGM_PWM_MAX_DUTY_CYCLE (BIT(8) - 1) + +#define LGM_PWM_DC_BITS 8 + +#define LGM_PWM_PERIOD_2WIRE_NSECS 40000000 +#define LGM_PWM_PERIOD_4WIRE_NSECS 40000 + +struct lgm_pwm_chip { + struct pwm_chip chip; + struct regmap *regmap; + struct clk *clk; + struct reset_control *rst; + u32 period; +}; + +static inline struct lgm_pwm_chip *to_lgm_pwm_chip(struct pwm_chip *chip) +{ + return container_of(chip, struct lgm_pwm_chip, chip); +} + +static int lgm_pwm_enable(struct pwm_chip *chip, bool enable) +{ + struct lgm_pwm_chip *pc = to_lgm_pwm_chip(chip); + struct regmap *regmap = pc->regmap; + + return regmap_update_bits(regmap, LGM_PWM_FAN_CON0, LGM_PWM_FAN_EN_MSK, + enable ? LGM_PWM_FAN_EN_EN : LGM_PWM_FAN_EN_DIS); +} + +static int lgm_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct lgm_pwm_chip *pc = to_lgm_pwm_chip(chip); + u32 duty_cycle, val; + int ret; + + /* + * The hardware only supports + * normal polarity and fixed period. + */ + if (state->polarity != PWM_POLARITY_NORMAL || + state->period < pc->period) + return -EINVAL; + + if (!state->enabled) { + ret = lgm_pwm_enable(chip, 0); + return ret; + } + + duty_cycle = min_t(u64, state->duty_cycle, pc->period); + val = duty_cycle * LGM_PWM_MAX_DUTY_CYCLE / pc->period; + + ret = regmap_update_bits(pc->regmap, LGM_PWM_FAN_CON0, LGM_PWM_FAN_DC_MSK, + FIELD_PREP(LGM_PWM_FAN_DC_MSK, val)); + if (ret) + return ret; + + ret = lgm_pwm_enable(chip, 1); + + return ret; +} + +static void lgm_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) +{ + struct lgm_pwm_chip *pc = to_lgm_pwm_chip(chip); + u32 duty, val; + + state->enabled = regmap_test_bits(pc->regmap, LGM_PWM_FAN_CON0, + LGM_PWM_FAN_EN_EN); + state->polarity = PWM_POLARITY_NORMAL; + state->period = pc->period; /* fixed period */ + + regmap_read(pc->regmap, LGM_PWM_FAN_CON0, &val); + duty = FIELD_GET(LGM_PWM_FAN_DC_MSK, val); + state->duty_cycle = DIV_ROUND_UP(duty * pc->period, + LGM_PWM_MAX_DUTY_CYCLE); +} + +static const struct pwm_ops lgm_pwm_ops = { + .get_state = lgm_pwm_get_state, + .apply = lgm_pwm_apply, + .owner = THIS_MODULE, +}; + +static void lgm_pwm_init(struct lgm_pwm_chip *pc) +{ + struct device *dev = pc->chip.dev; + struct regmap *regmap = pc->regmap; + u32 max_rpm, fan_wire, con0_val, con0_mask; + + if (device_property_read_u32(dev, "pwm-fanmode", &fan_wire)) + fan_wire = 2; /* default is 2 wire mode */ + + con0_mask = LGM_PWM_FAN_MODE_MSK; + + switch (fan_wire) { + case 4: + con0_val = FIELD_PREP(LGM_PWM_FAN_MODE_MSK, LGM_PWM_FAN_MODE_4WIRE); + pc->period = LGM_PWM_PERIOD_4WIRE_NSECS; + break; + default: + /* default is 2wire mode */ + con0_val = FIELD_PREP(LGM_PWM_FAN_MODE_MSK, LGM_PWM_FAN_MODE_2WIRE); + pc->period = LGM_PWM_PERIOD_2WIRE_NSECS; + break; + } + + if (device_property_read_u32(dev, "pwm-maxrpm", &max_rpm)) + max_rpm = LGM_PWM_DEFAULT_RPM; + + max_rpm = min_t(u32, max_rpm, LGM_PWM_MAX_RPM); + if (max_rpm == 0) + max_rpm = LGM_PWM_DEFAULT_RPM; + + regmap_update_bits(regmap, LGM_PWM_FAN_CON1, LGM_PWM_FAN_MAX_RPM_MSK, max_rpm); + regmap_update_bits(regmap, LGM_PWM_FAN_CON0, con0_mask, con0_val); +} + +static const struct regmap_config lgm_pwm_regmap_config = { + .reg_bits = 32, + .reg_stride = 4, + .val_bits = 32, +}; + +static int lgm_pwm_probe(struct platform_device *pdev) +{ + struct lgm_pwm_chip *pc; + struct device *dev = &pdev->dev; + void __iomem *io_base; + int ret; + + pc = devm_kzalloc(dev, sizeof(*pc), GFP_KERNEL); + if (!pc) + return -ENOMEM; + + io_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(io_base)) + return PTR_ERR(io_base); + + pc->regmap = devm_regmap_init_mmio(dev, io_base, &lgm_pwm_regmap_config); + if (IS_ERR(pc->regmap)) { + ret = PTR_ERR(pc->regmap); + if (ret != -EPROBE_DEFER) + dev_err(dev, "failed to init register map: %pe\n", + pc->regmap); + return ret; + } + + pc->clk = devm_clk_get(dev, NULL); + if (IS_ERR(pc->clk)) { + ret = PTR_ERR(pc->clk); + if (ret != -EPROBE_DEFER) + dev_err(dev, "failed to get clock: %pe\n", pc->clk); + return ret; + } + + pc->rst = devm_reset_control_get_exclusive(dev, NULL); + if (IS_ERR(pc->rst)) { + ret = PTR_ERR(pc->rst); + if (ret != -EPROBE_DEFER) + dev_err(dev, "failed to get reset control: %pe\n", + pc->rst); + return ret; + } + + ret = reset_control_deassert(pc->rst); + if (ret) { + if (ret != -EPROBE_DEFER) + dev_err(dev, "cannot deassert reset control: %pe\n", + ERR_PTR(ret)); + return ret; + } + + ret = clk_prepare_enable(pc->clk); + if (ret) { + dev_err(dev, "failed to enable clock\n"); + reset_control_assert(pc->rst); + return ret; + } + + pc->chip.dev = dev; + pc->chip.ops = &lgm_pwm_ops; + pc->chip.npwm = 1; + + lgm_pwm_init(pc); + + ret = pwmchip_add(&pc->chip); + if (ret < 0) { + dev_err(dev, "failed to add PWM chip: %pe\n", ERR_PTR(ret)); + clk_disable_unprepare(pc->clk); + reset_control_assert(pc->rst); + return ret; + } + + platform_set_drvdata(pdev, pc); + return 0; +} + +static int lgm_pwm_remove(struct platform_device *pdev) +{ + struct lgm_pwm_chip *pc = platform_get_drvdata(pdev); + int ret; + + ret = pwmchip_remove(&pc->chip); + if (ret < 0) + return ret; + + clk_disable_unprepare(pc->clk); + reset_control_assert(pc->rst); + + return 0; +} + +static const struct of_device_id lgm_pwm_of_match[] = { + { .compatible = "intel,lgm-pwm" }, + { } +}; +MODULE_DEVICE_TABLE(of, lgm_pwm_of_match); + +static struct platform_driver lgm_pwm_driver = { + .driver = { + .name = "intel-pwm", + .of_match_table = lgm_pwm_of_match, + }, + .probe = lgm_pwm_probe, + .remove = lgm_pwm_remove, +}; +module_platform_driver(lgm_pwm_driver);