From patchwork Fri Oct 2 14:59:47 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Antoine Tenart X-Patchwork-Id: 7316941 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 869F6BEEA4 for ; Fri, 2 Oct 2015 15:03:40 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 605D2208DF for ; Fri, 2 Oct 2015 15:03:39 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0B3F5208F0 for ; Fri, 2 Oct 2015 15:03:38 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Zi1pR-0000fo-Hv; Fri, 02 Oct 2015 15:00:57 +0000 Received: from down.free-electrons.com ([37.187.137.238] helo=mail.free-electrons.com) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Zi1ox-0000Cl-GT for linux-arm-kernel@lists.infradead.org; Fri, 02 Oct 2015 15:00:30 +0000 Received: by mail.free-electrons.com (Postfix, from userid 110) id EAD713182; Fri, 2 Oct 2015 17:00:10 +0200 (CEST) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from localhost (nat1.foo.tf [195.154.42.251]) by mail.free-electrons.com (Postfix) with ESMTPSA id B87372DC; Fri, 2 Oct 2015 16:59:51 +0200 (CEST) From: Antoine Tenart To: sebastian.hesselbarth@gmail.com, thierry.reding@gmail.com Subject: [PATCH v7 2/5] pwm: add the Berlin pwm controller driver Date: Fri, 2 Oct 2015 16:59:47 +0200 Message-Id: <1443797990-10809-3-git-send-email-antoine.tenart@free-electrons.com> X-Mailer: git-send-email 2.6.0 In-Reply-To: <1443797990-10809-1-git-send-email-antoine.tenart@free-electrons.com> References: <1443797990-10809-1-git-send-email-antoine.tenart@free-electrons.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20151002_080027_868134_9D3C84DB X-CRM114-Status: GOOD ( 22.22 ) X-Spam-Score: -2.6 (--) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: zmxu@marvell.com, jszhang@marvell.com, linux-pwm@vger.kernel.org, Antoine Tenart , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Add a PWM controller driver for the Marvell Berlin SoCs. This PWM controller has 4 channels. Signed-off-by: Antoine Tenart Acked-by: Sebastian Hesselbarth --- drivers/pwm/Kconfig | 9 ++ drivers/pwm/Makefile | 1 + drivers/pwm/pwm-berlin.c | 221 +++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 231 insertions(+) create mode 100644 drivers/pwm/pwm-berlin.c diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 062630ab7424..f3e8b7566ce5 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -92,6 +92,15 @@ config PWM_BCM2835 To compile this driver as a module, choose M here: the module will be called pwm-bcm2835. +config PWM_BERLIN + tristate "Berlin PWM support" + depends on ARCH_BERLIN + help + PWM framework driver for Berlin. + + To compile this driver as a module, choose M here: the module + will be called pwm-berlin. + config PWM_BFIN tristate "Blackfin PWM support" depends on BFIN_GPTIMERS diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index a0e00c09ead3..601833d82da5 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -6,6 +6,7 @@ obj-$(CONFIG_PWM_ATMEL_HLCDC_PWM) += pwm-atmel-hlcdc.o obj-$(CONFIG_PWM_ATMEL_TCB) += pwm-atmel-tcb.o obj-$(CONFIG_PWM_BCM_KONA) += pwm-bcm-kona.o obj-$(CONFIG_PWM_BCM2835) += pwm-bcm2835.o +obj-$(CONFIG_PWM_BERLIN) += pwm-berlin.o obj-$(CONFIG_PWM_BFIN) += pwm-bfin.o obj-$(CONFIG_PWM_CLPS711X) += pwm-clps711x.o obj-$(CONFIG_PWM_CRC) += pwm-crc.o diff --git a/drivers/pwm/pwm-berlin.c b/drivers/pwm/pwm-berlin.c new file mode 100644 index 000000000000..981038740577 --- /dev/null +++ b/drivers/pwm/pwm-berlin.c @@ -0,0 +1,221 @@ +/* + * Marvell Berlin PWM driver + * + * Copyright (C) 2015 Marvell Technology Group Ltd. + * + * Author: Antoine Tenart + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include +#include +#include +#include +#include +#include + +#define BERLIN_PWM_EN 0x0 +#define BERLIN_PWM_ENABLE BIT(0) +#define BERLIN_PWM_CONTROL 0x4 +#define BERLIN_PWM_PRESCALE_MASK 0x7 +#define BERLIN_PWM_PRESCALE_MAX 4096 +#define BERLIN_PWM_INVERT_POLARITY BIT(3) +#define BERLIN_PWM_DUTY 0x8 +#define BERLIN_PWM_TCNT 0xc +#define BERLIN_PWM_MAX_TCNT 65535 + +struct berlin_pwm_chip { + struct pwm_chip chip; + struct clk *clk; + void __iomem *base; +}; + +#define to_berlin_pwm_chip(chip) \ + container_of((chip), struct berlin_pwm_chip, chip) + +static const u32 prescaler_table[] = { + 1, 4, 8, 16, 64, 256, 1024, 4096 +}; + +static inline u32 berlin_pwm_readl(struct berlin_pwm_chip *chip, + unsigned int channel, unsigned long offset) +{ + return readl_relaxed(chip->base + channel * 0x10 + offset); +} + +static inline void berlin_pwm_writel(struct berlin_pwm_chip *chip, + unsigned int channel, u32 val, + unsigned long offset) +{ + writel_relaxed(val, chip->base + channel * 0x10 + offset); +} + +static int berlin_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm_dev, + int duty_ns, int period_ns) +{ + struct berlin_pwm_chip *pwm = to_berlin_pwm_chip(chip); + unsigned int prescale; + u32 val, duty, period; + u64 cycles, tmp; + + cycles = clk_get_rate(pwm->clk); + cycles *= period_ns; + do_div(cycles, NSEC_PER_SEC); + + for (prescale = 0; prescale < ARRAY_SIZE(prescaler_table); prescale++) { + tmp = cycles; + do_div(tmp, prescaler_table[prescale]); + + if (tmp <= BERLIN_PWM_MAX_TCNT) + break; + } + + if (tmp > BERLIN_PWM_MAX_TCNT) + goto err_range; + + period = tmp; + cycles = tmp * duty_ns; + do_div(cycles, period_ns); + duty = cycles; + + val = berlin_pwm_readl(pwm, pwm_dev->hwpwm, BERLIN_PWM_CONTROL); + val &= ~BERLIN_PWM_PRESCALE_MASK; + val |= prescale; + berlin_pwm_writel(pwm, pwm_dev->hwpwm, val, BERLIN_PWM_CONTROL); + + berlin_pwm_writel(pwm, pwm_dev->hwpwm, duty, BERLIN_PWM_DUTY); + berlin_pwm_writel(pwm, pwm_dev->hwpwm, period, BERLIN_PWM_TCNT); + + return 0; + +err_range: + return -ERANGE; +} + +static int berlin_pwm_set_polarity(struct pwm_chip *chip, + struct pwm_device *pwm_dev, + enum pwm_polarity polarity) +{ + struct berlin_pwm_chip *pwm = to_berlin_pwm_chip(chip); + u32 val; + + val = berlin_pwm_readl(pwm, pwm_dev->hwpwm, BERLIN_PWM_CONTROL); + + if (polarity == PWM_POLARITY_NORMAL) + val &= ~BERLIN_PWM_INVERT_POLARITY; + else + val |= BERLIN_PWM_INVERT_POLARITY; + + berlin_pwm_writel(pwm, pwm_dev->hwpwm, val, BERLIN_PWM_CONTROL); + + return 0; +} + +static int berlin_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm_dev) +{ + struct berlin_pwm_chip *pwm = to_berlin_pwm_chip(chip); + u32 val; + + val = berlin_pwm_readl(pwm, pwm_dev->hwpwm, BERLIN_PWM_EN); + val |= BERLIN_PWM_ENABLE; + berlin_pwm_writel(pwm, pwm_dev->hwpwm, val, BERLIN_PWM_EN); + + return 0; +} + +static void berlin_pwm_disable(struct pwm_chip *chip, + struct pwm_device *pwm_dev) +{ + struct berlin_pwm_chip *pwm = to_berlin_pwm_chip(chip); + u32 val; + + val = berlin_pwm_readl(pwm, pwm_dev->hwpwm, BERLIN_PWM_EN); + val &= ~BERLIN_PWM_ENABLE; + berlin_pwm_writel(pwm, pwm_dev->hwpwm, val, BERLIN_PWM_EN); +} + +static const struct pwm_ops berlin_pwm_ops = { + .config = berlin_pwm_config, + .set_polarity = berlin_pwm_set_polarity, + .enable = berlin_pwm_enable, + .disable = berlin_pwm_disable, + .owner = THIS_MODULE, +}; + +static const struct of_device_id berlin_pwm_match[] = { + { .compatible = "marvell,berlin-pwm" }, + { }, +}; +MODULE_DEVICE_TABLE(of, berlin_pwm_match); + +static int berlin_pwm_probe(struct platform_device *pdev) +{ + struct berlin_pwm_chip *pwm; + struct resource *res; + int ret; + + pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL); + if (!pwm) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + pwm->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(pwm->base)) + return PTR_ERR(pwm->base); + + pwm->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(pwm->clk)) + return PTR_ERR(pwm->clk); + + ret = clk_prepare_enable(pwm->clk); + if (ret) + return ret; + + pwm->chip.dev = &pdev->dev; + pwm->chip.ops = &berlin_pwm_ops; + pwm->chip.base = -1; + pwm->chip.npwm = 4; + pwm->chip.can_sleep = true; + pwm->chip.of_xlate = of_pwm_xlate_with_flags; + pwm->chip.of_pwm_n_cells = 3; + + ret = pwmchip_add(&pwm->chip); + if (ret < 0) { + clk_disable_unprepare(pwm->clk); + + dev_err(&pdev->dev, "Failed to add PWM chip: %d\n", ret); + return ret; + } + + platform_set_drvdata(pdev, pwm); + + return 0; +} + +static int berlin_pwm_remove(struct platform_device *pdev) +{ + struct berlin_pwm_chip *pwm = platform_get_drvdata(pdev); + int ret; + + ret = pwmchip_remove(&pwm->chip); + clk_disable_unprepare(pwm->clk); + + return ret; +} + +static struct platform_driver berlin_pwm_driver = { + .probe = berlin_pwm_probe, + .remove = berlin_pwm_remove, + .driver = { + .name = "berlin-pwm", + .of_match_table = berlin_pwm_match, + }, +}; +module_platform_driver(berlin_pwm_driver); + +MODULE_AUTHOR("Antoine Tenart "); +MODULE_DESCRIPTION("Marvell Berlin PWM driver"); +MODULE_LICENSE("GPL v2");