From patchwork Tue Mar 17 20:50:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Walle X-Patchwork-Id: 11443993 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9173090 for ; Tue, 17 Mar 2020 20:51:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5D1BD20776 for ; Tue, 17 Mar 2020 20:51:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=walle.cc header.i=@walle.cc header.b="vNXBPAAH" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727228AbgCQUvc (ORCPT ); Tue, 17 Mar 2020 16:51:32 -0400 Received: from ssl.serverraum.org ([176.9.125.105]:40643 "EHLO ssl.serverraum.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726971AbgCQUu6 (ORCPT ); Tue, 17 Mar 2020 16:50:58 -0400 Received: from apollo.fritz.box (unknown [IPv6:2a02:810c:c200:2e91:6257:18ff:fec4:ca34]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-384) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ssl.serverraum.org (Postfix) with ESMTPSA id 20D3323EA9; Tue, 17 Mar 2020 21:50:54 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=walle.cc; s=mail2016061301; t=1584478254; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=twd0Ppy8uMjyLaeWbisE1KI8OORpU7NS5ZQrPhswzQo=; b=vNXBPAAH1IrB2oMPSmrVTqppJ4sWHDZ3wEGTJho7rCtDSknH6elwMwiFpJ7GDwL4OHIPDG hBANb2hj37TVSfZyhO9shM0ct0BS7uXXrWdIzHJPFD+9xCaDs0ejBX5yJljtsGvchj6rnD 4+4szyk0Pn9J92ZfLEcq6jv1In4IBCw= From: Michael Walle To: linux-gpio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-pwm@vger.kernel.org, linux-watchdog@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Linus Walleij , Bartosz Golaszewski , Rob Herring , Jean Delvare , Guenter Roeck , Lee Jones , Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= , Wim Van Sebroeck , Shawn Guo , Li Yang , Thomas Gleixner , Jason Cooper , Marc Zyngier , Michael Walle Subject: [PATCH 10/18] pwm: add support for sl28cpld PWM controller Date: Tue, 17 Mar 2020 21:50:09 +0100 Message-Id: <20200317205017.28280-11-michael@walle.cc> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200317205017.28280-1-michael@walle.cc> References: <20200317205017.28280-1-michael@walle.cc> MIME-Version: 1.0 X-Spamd-Bar: ++++++ X-Spam-Level: ****** X-Rspamd-Server: web X-Spam-Status: Yes, score=6.40 X-Spam-Score: 6.40 X-Rspamd-Queue-Id: 20D3323EA9 X-Spamd-Result: default: False [6.40 / 15.00]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; R_MISSING_CHARSET(2.50)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; TAGGED_RCPT(0.00)[dt]; MIME_GOOD(-0.10)[text/plain]; BROKEN_CONTENT_TYPE(1.50)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; NEURAL_SPAM(0.00)[0.506]; DKIM_SIGNED(0.00)[]; RCPT_COUNT_TWELVE(0.00)[22]; MID_CONTAINS_FROM(1.00)[]; RCVD_COUNT_ZERO(0.00)[0]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:31334, ipnet:2a02:810c:8000::/33, country:DE]; FREEMAIL_CC(0.00)[linaro.org,baylibre.com,kernel.org,suse.com,roeck-us.net,gmail.com,pengutronix.de,linux-watchdog.org,nxp.com,linutronix.de,lakedaemon.net,walle.cc]; SUSPICIOUS_RECIPS(1.50)[] X-Spam: Yes Sender: linux-watchdog-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-watchdog@vger.kernel.org This adds support for the PWM controller of the sl28cpld board management controller. This is part of a multi-function device driver. Signed-off-by: Michael Walle --- drivers/pwm/Kconfig | 10 ++ drivers/pwm/Makefile | 1 + drivers/pwm/pwm-sl28cpld.c | 192 +++++++++++++++++++++++++++++++++++++ 3 files changed, 203 insertions(+) create mode 100644 drivers/pwm/pwm-sl28cpld.c diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 30190beeb6e9..516d70873b4c 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -413,6 +413,16 @@ config PWM_SIFIVE To compile this driver as a module, choose M here: the module will be called pwm-sifive. +config PWM_SL28CPLD + tristate "Kontron sl28 PWM support" + depends on MFD_SL28CPLD + help + Generic PWM framework driver for board management controller + found on the Kontron sl28 CPLD. + + To compile this driver as a module, choose M here: the module + will be called pwm-sl28cpld. + config PWM_SPEAR tristate "STMicroelectronics SPEAr PWM support" depends on PLAT_SPEAR diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index 9a475073dafc..2c2b569dcde9 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -40,6 +40,7 @@ obj-$(CONFIG_PWM_RENESAS_TPU) += pwm-renesas-tpu.o obj-$(CONFIG_PWM_ROCKCHIP) += pwm-rockchip.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_SPEAR) += pwm-spear.o obj-$(CONFIG_PWM_SPRD) += pwm-sprd.o obj-$(CONFIG_PWM_STI) += pwm-sti.o diff --git a/drivers/pwm/pwm-sl28cpld.c b/drivers/pwm/pwm-sl28cpld.c new file mode 100644 index 000000000000..758f46898da6 --- /dev/null +++ b/drivers/pwm/pwm-sl28cpld.c @@ -0,0 +1,192 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * SMARC-sAL28 PWM driver. + * + * Copyright 2019 Kontron Europe GmbH + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * PWM timer block registers. + */ +#define SL28CPLD_PWM_CTRL 0 +#define PWM_ENABLE BIT(7) +#define PWM_MODE_250HZ 0 +#define PWM_MODE_500HZ 1 +#define PWM_MODE_1KHZ 2 +#define PWM_MODE_2KHZ 3 +#define PWM_MODE_MASK GENMASK(1, 0) +#define SL28CPLD_PWM_CYCLE 1 +#define PWM_CYCLE_MAX 0x7f + +struct sl28cpld_pwm { + struct pwm_chip pwm_chip; + struct regmap *regmap; + u32 offset; +}; + +struct sl28cpld_pwm_periods { + u8 ctrl; + unsigned long duty_cycle; +}; + +struct sl28cpld_pwm_config { + unsigned long period_ns; + u8 max_duty_cycle; +}; + +static struct sl28cpld_pwm_config sl28cpld_pwm_config[] = { + [PWM_MODE_250HZ] = { .period_ns = 4000000, .max_duty_cycle = 0x80 }, + [PWM_MODE_500HZ] = { .period_ns = 2000000, .max_duty_cycle = 0x40 }, + [PWM_MODE_1KHZ] = { .period_ns = 1000000, .max_duty_cycle = 0x20 }, + [PWM_MODE_2KHZ] = { .period_ns = 500000, .max_duty_cycle = 0x10 }, +}; + +static inline struct sl28cpld_pwm *to_sl28cpld_pwm(struct pwm_chip *chip) +{ + return container_of(chip, struct sl28cpld_pwm, pwm_chip); +} + +static void sl28cpld_pwm_get_state(struct pwm_chip *chip, + struct pwm_device *pwm, + struct pwm_state *state) +{ + struct sl28cpld_pwm *spc = to_sl28cpld_pwm(chip); + static struct sl28cpld_pwm_config *config; + unsigned int reg; + unsigned long cycle; + unsigned int mode; + + regmap_read(spc->regmap, spc->offset + SL28CPLD_PWM_CTRL, ®); + + state->enabled = reg & PWM_ENABLE; + + mode = FIELD_GET(PWM_MODE_MASK, reg); + config = &sl28cpld_pwm_config[mode]; + state->period = config->period_ns; + + regmap_read(spc->regmap, spc->offset + SL28CPLD_PWM_CYCLE, ®); + cycle = reg * config->period_ns; + state->duty_cycle = DIV_ROUND_CLOSEST_ULL(cycle, + config->max_duty_cycle); +} + +static int sl28cpld_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct sl28cpld_pwm *spc = to_sl28cpld_pwm(chip); + struct sl28cpld_pwm_config *config; + unsigned long long cycle; + int ret; + int mode; + u8 ctrl; + + /* update config, first search best matching period */ + for (mode = 0; mode < ARRAY_SIZE(sl28cpld_pwm_config); mode++) { + config = &sl28cpld_pwm_config[mode]; + if (state->period == config->period_ns) + break; + } + + if (mode == ARRAY_SIZE(sl28cpld_pwm_config)) + return -EINVAL; + + ctrl = FIELD_PREP(PWM_MODE_MASK, mode); + if (state->enabled) + ctrl |= PWM_ENABLE; + + cycle = state->duty_cycle * config->max_duty_cycle; + do_div(cycle, state->period); + + /* + * The hardware doesn't allow to set max_duty_cycle if the + * 250Hz mode is enabled. But since this is "all-high" output + * just use the 500Hz mode with the duty cycle to max value. + */ + if (cycle == config->max_duty_cycle) { + ctrl &= ~PWM_MODE_MASK; + ctrl |= FIELD_PREP(PWM_MODE_MASK, PWM_MODE_500HZ); + cycle = PWM_CYCLE_MAX; + } + + ret = regmap_write(spc->regmap, + spc->offset + SL28CPLD_PWM_CTRL, ctrl); + if (ret) + return ret; + + return regmap_write(spc->regmap, + spc->offset + SL28CPLD_PWM_CYCLE, (u8)cycle); +} + +static const struct pwm_ops sl28cpld_pwm_ops = { + .apply = sl28cpld_pwm_apply, + .get_state = sl28cpld_pwm_get_state, + .owner = THIS_MODULE, +}; + +static int sl28cpld_pwm_probe(struct platform_device *pdev) +{ + struct sl28cpld_pwm *pwm; + struct pwm_chip *chip; + struct resource *res; + int ret; + + pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL); + if (!pwm) + return -ENOMEM; + + if (!pdev->dev.parent) + return -ENODEV; + + pwm->regmap = dev_get_regmap(pdev->dev.parent, NULL); + if (!pwm->regmap) + return -ENODEV; + + res = platform_get_resource(pdev, IORESOURCE_REG, 0); + if (!res) + return -EINVAL; + pwm->offset = res->start; + + /* initialize struct gpio_chip */ + chip = &pwm->pwm_chip; + chip->dev = &pdev->dev; + chip->ops = &sl28cpld_pwm_ops; + chip->base = -1; + chip->npwm = 1; + + ret = pwmchip_add(&pwm->pwm_chip); + if (ret < 0) + return ret; + + platform_set_drvdata(pdev, pwm); + + return 0; +} + +static int sl28cpld_pwm_remove(struct platform_device *pdev) +{ + struct sl28cpld_pwm *pwm = platform_get_drvdata(pdev); + + return pwmchip_remove(&pwm->pwm_chip); +} + +static struct platform_driver sl28cpld_pwm_driver = { + .probe = sl28cpld_pwm_probe, + .remove = sl28cpld_pwm_remove, + .driver = { + .name = "sl28cpld-pwm", + }, +}; +module_platform_driver(sl28cpld_pwm_driver); + +MODULE_DESCRIPTION("sl28cpld PWM Driver"); +MODULE_LICENSE("GPL");