From patchwork Thu Aug 12 21:57:24 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: wellsk40@gmail.com X-Patchwork-Id: 61648 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from mail-qy0-f184.google.com (mail-qy0-f184.google.com [209.85.216.184]) by ozlabs.org (Postfix) with ESMTP id 26C4AB70D0 for ; Fri, 13 Aug 2010 07:57:37 +1000 (EST) Received: by qyk10 with SMTP id 10sf9274319qyk.11 for ; Thu, 12 Aug 2010 14:57:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlegroups.com; s=beta; h=domainkey-signature:received:mime-version:x-beenthere:received :received:received:received:received-spf:received:received:received :from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references :x-original-sender:x-original-authentication-results:reply-to :precedence:mailing-list:list-id:list-post:list-help:list-archive :sender:list-subscribe:list-unsubscribe:content-type; bh=iwnARBQtJqbbLlUHxDoqO9UdPlrny29jJ7r1WkB9Ex8=; b=yptoOtZ4qMbK3JEEsXSfhtIaPAq4T8XCzw+xc9OKuT3Gmpx2e2SfztZO/5XO3T9qpo 7X/IgaBf6++H7LuaXg7LHwS72P7H0KB7sR0SzDRogtdip+8IaQXuKT75vn50isEs5V+U oR65/ELJzql87wmrs68xMA/Iu0bofCsr1S21g= DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlegroups.com; s=beta; h=mime-version:x-beenthere:received-spf:from:to:cc:subject:date :message-id:x-mailer:in-reply-to:references:x-original-sender :x-original-authentication-results:reply-to:precedence:mailing-list :list-id:list-post:list-help:list-archive:sender:list-subscribe :list-unsubscribe:content-type; b=phTu3driwmMvopPqB0+CEG7g0R6IV22ZVs65ZVTNZhGZtiQjOeJZt4VDHCfoX2j5Z0 hjqEeuYp4ErFTjFUhuJugLFghCdWdLgU6yEYTavOaoWc7ncTijFswls/GjjmUYy62TiR uSddbZ1NQx//aFNCKe/4Dt9xHEZ0SEUFhyK3Q= Received: by 10.229.2.167 with SMTP id 39mr123305qcj.49.1281650255982; Thu, 12 Aug 2010 14:57:35 -0700 (PDT) MIME-Version: 1.0 X-BeenThere: rtc-linux@googlegroups.com Received: by 10.229.207.1 with SMTP id fw1ls709032qcb.1.p; Thu, 12 Aug 2010 14:57:35 -0700 (PDT) Received: by 10.229.190.203 with SMTP id dj11mr81657qcb.9.1281650255615; Thu, 12 Aug 2010 14:57:35 -0700 (PDT) Received: by 10.229.190.203 with SMTP id dj11mr81656qcb.9.1281650255585; Thu, 12 Aug 2010 14:57:35 -0700 (PDT) Received: from mail-vw0-f45.google.com (mail-vw0-f45.google.com [209.85.212.45]) by gmr-mx.google.com with ESMTP id y16si1068907qce.8.2010.08.12.14.57.34; Thu, 12 Aug 2010 14:57:34 -0700 (PDT) Received-SPF: pass (google.com: domain of wellsk40@gmail.com designates 209.85.212.45 as permitted sender) client-ip=209.85.212.45; Received: by vws19 with SMTP id 19so1015580vws.32 for ; Thu, 12 Aug 2010 14:57:34 -0700 (PDT) Received: by 10.220.100.67 with SMTP id x3mr485763vcn.122.1281650254310; Thu, 12 Aug 2010 14:57:34 -0700 (PDT) Received: from localhost.localdomain (66-193-100-242.static.twtelecom.net [66.193.100.242]) by mx.google.com with ESMTPS id m30sm1214072vbr.19.2010.08.12.14.57.32 (version=SSLv3 cipher=RC4-MD5); Thu, 12 Aug 2010 14:57:33 -0700 (PDT) From: wellsk40@gmail.com To: rtc-linux@googlegroups.com Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, durgesh.pattamatta@nxp.com, Kevin Wells Subject: [rtc-linux] [PATCH] rtc: rtc-lpc32xx: Introduce RTC driver for the LPC32XX SoC (v3) Date: Thu, 12 Aug 2010 14:57:24 -0700 Message-Id: <1281650244-9889-2-git-send-email-wellsk40@gmail.com> X-Mailer: git-send-email 1.7.1.1 In-Reply-To: <1281650244-9889-1-git-send-email-wellsk40@gmail.com> References: <1281650244-9889-1-git-send-email-wellsk40@gmail.com> X-Original-Sender: wellsk40@gmail.com X-Original-Authentication-Results: gmr-mx.google.com; spf=pass (google.com: domain of wellsk40@gmail.com designates 209.85.212.45 as permitted sender) smtp.mail=wellsk40@gmail.com; dkim=pass (test mode) header.i=@gmail.com Reply-To: rtc-linux@googlegroups.com Precedence: list Mailing-list: list rtc-linux@googlegroups.com; contact rtc-linux+owners@googlegroups.com List-ID: List-Post: , List-Help: , List-Archive: Sender: rtc-linux@googlegroups.com List-Subscribe: , List-Unsubscribe: , From: Kevin Wells This patch contains the RTC driver for the built-in RTC in the LPC32XX SoC. This patch includes updates from the initial review comments and updates from the v2 review. Signed-off-by: Kevin Wells Signed-off-by: Durgesh Pattamatta --- drivers/rtc/Kconfig | 9 + drivers/rtc/Makefile | 1 + drivers/rtc/rtc-lpc32xx.c | 410 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 420 insertions(+), 0 deletions(-) create mode 100644 drivers/rtc/rtc-lpc32xx.c diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index 48ca713..774a65a 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -952,4 +952,13 @@ config RTC_DRV_JZ4740 This driver can also be buillt as a module. If so, the module will be called rtc-jz4740. +config RTC_DRV_LPC32XX + depends on ARCH_LPC32XX + tristate "NXP LPC32XX RTC" + help + This enables support for the NXP RTC in the LPC32XX + + This driver can also be buillt as a module. If so, the module + will be called rtc-lpc32xx. + endif # RTC_CLASS diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index 0f207b3..7a7cb32 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -51,6 +51,7 @@ obj-$(CONFIG_RTC_DRV_IMXDI) += rtc-imxdi.o obj-$(CONFIG_RTC_DRV_ISL1208) += rtc-isl1208.o obj-$(CONFIG_RTC_DRV_ISL12022) += rtc-isl12022.o obj-$(CONFIG_RTC_DRV_JZ4740) += rtc-jz4740.o +obj-$(CONFIG_RTC_DRV_LPC32XX) += rtc-lpc32xx.o obj-$(CONFIG_RTC_DRV_M41T80) += rtc-m41t80.o obj-$(CONFIG_RTC_DRV_M41T94) += rtc-m41t94.o obj-$(CONFIG_RTC_DRV_M48T35) += rtc-m48t35.o diff --git a/drivers/rtc/rtc-lpc32xx.c b/drivers/rtc/rtc-lpc32xx.c new file mode 100644 index 0000000..b63137d --- /dev/null +++ b/drivers/rtc/rtc-lpc32xx.c @@ -0,0 +1,410 @@ +/* + * Copyright (C) 2010 NXP Semiconductors + * + * 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. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * Clock and Power control register offsets + */ +#define LPC32XX_RTC_UCOUNT 0x00 +#define LPC32XX_RTC_DCOUNT 0x04 +#define LPC32XX_RTC_MATCH0 0x08 +#define LPC32XX_RTC_MATCH1 0x0C +#define LPC32XX_RTC_CTRL 0x10 +#define LPC32XX_RTC_INTSTAT 0x14 +#define LPC32XX_RTC_KEY 0x18 +#define LPC32XX_RTC_SRAM 0x80 + +#define LPC32XX_RTC_MATCH0_EN (1 << 0) +#define LPC32XX_RTC_MATCH1_EN (1 << 1) +#define LPC32XX_RTC_ONSW_MATCH0_EN (1 << 2) +#define LPC32XX_RTC_ONSW_MATCH1_EN (1 << 3) +#define LPC32XX_RTC_SW_RESET (1 << 4) +#define LPC32XX_RTC_CNTR_DIS (1 << 6) +#define LPC32XX_RTC_ONSW_FORCE_HIGH (1 << 7) + +#define LPC32XX_RTC_MATCH0_INT_STS (1 << 0) +#define LPC32XX_RTC_MATCH1_INT_STS (1 << 1) +#define LPC32XX_RTC_ONSW_INT_STS (1 << 2) + +#define LPC32XX_RTC_KEY_ONSW_LOADVAL 0xB5C13F27 + +#define RTC_NAME "rtc-lpc32xx" + +#define rtc_readl(dev, reg) \ + __raw_readl((dev)->rtc_base + (reg)) +#define rtc_writel(dev, reg, val) \ + __raw_writel((val), (dev)->rtc_base + (reg)) + +struct lpc32xx_rtc { + void __iomem *rtc_base; + int irq; + unsigned char alarm_enabled; + struct rtc_device *rtc; + spinlock_t lock; +}; + +static int lpc32xx_rtc_read_time(struct device *dev, struct rtc_time *time) +{ + unsigned long elapsed_sec; + struct lpc32xx_rtc *rtc = dev_get_drvdata(dev); + + elapsed_sec = rtc_readl(rtc, LPC32XX_RTC_UCOUNT); + rtc_time_to_tm(elapsed_sec, time); + + return rtc_valid_tm(time); +} + +static int lpc32xx_rtc_set_mmss(struct device *dev, unsigned long secs) +{ + struct lpc32xx_rtc *rtc = dev_get_drvdata(dev); + u32 tmp; + + spin_lock_irq(&rtc->lock); + + /* RTC must be disabled during count update */ + tmp = rtc_readl(rtc, LPC32XX_RTC_CTRL); + rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp | LPC32XX_RTC_CNTR_DIS); + rtc_writel(rtc, LPC32XX_RTC_UCOUNT, secs); + rtc_writel(rtc, LPC32XX_RTC_DCOUNT, 0xFFFFFFFF - secs); + rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp &= ~LPC32XX_RTC_CNTR_DIS); + + spin_unlock_irq(&rtc->lock); + + return 0; +} + +static int lpc32xx_rtc_read_alarm(struct device *dev, + struct rtc_wkalrm *wkalrm) +{ + struct lpc32xx_rtc *rtc = dev_get_drvdata(dev); + + rtc_time_to_tm(rtc_readl(rtc, LPC32XX_RTC_MATCH0), &wkalrm->time); + wkalrm->enabled = rtc->alarm_enabled; + wkalrm->pending = !!(rtc_readl(rtc, LPC32XX_RTC_INTSTAT) & + LPC32XX_RTC_MATCH0_INT_STS); + + return rtc_valid_tm(&wkalrm->time); +} + +static int lpc32xx_rtc_set_alarm(struct device *dev, + struct rtc_wkalrm *wkalrm) +{ + struct lpc32xx_rtc *rtc = dev_get_drvdata(dev); + unsigned long alarmsecs; + u32 tmp; + int ret; + + ret = rtc_tm_to_time(&wkalrm->time, &alarmsecs); + if (ret < 0) { + dev_warn(dev, "Failed to convert time: %d\n", ret); + return ret; + } + + spin_lock_irq(&rtc->lock); + + /* Disable alarm during update */ + tmp = rtc_readl(rtc, LPC32XX_RTC_CTRL); + rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp & ~LPC32XX_RTC_MATCH0_EN); + + rtc_writel(rtc, LPC32XX_RTC_MATCH0, alarmsecs); + + rtc->alarm_enabled = wkalrm->enabled; + if (wkalrm->enabled) { + rtc_writel(rtc, LPC32XX_RTC_INTSTAT, + LPC32XX_RTC_MATCH0_INT_STS); + rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp | + LPC32XX_RTC_MATCH0_EN); + } + + spin_unlock_irq(&rtc->lock); + + return 0; +} + +static int lpc32xx_rtc_alarm_irq_enable(struct device *dev, + unsigned int enabled) +{ + struct lpc32xx_rtc *rtc = dev_get_drvdata(dev); + u32 tmp; + + spin_lock_irq(&rtc->lock); + tmp = rtc_readl(rtc, LPC32XX_RTC_CTRL); + + if (enabled) { + rtc->alarm_enabled = 1; + tmp |= LPC32XX_RTC_MATCH0_EN; + } else { + rtc->alarm_enabled = 0; + tmp &= ~LPC32XX_RTC_MATCH0_EN; + } + + rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp); + spin_unlock_irq(&rtc->lock); + + return 0; +} + +static irqreturn_t lpc32xx_rtc_alarm_interrupt(int irq, void *dev) +{ + struct lpc32xx_rtc *rtc = dev; + + spin_lock(&rtc->lock); + + /* Disable alarm interrupt */ + rtc_writel(rtc, LPC32XX_RTC_CTRL, + rtc_readl(rtc, LPC32XX_RTC_CTRL) & ~LPC32XX_RTC_MATCH0_EN); + rtc->alarm_enabled = 0; + + /* + * Write a large value to the match value so the RTC won't + * keep firing the match status + */ + rtc_writel(rtc, LPC32XX_RTC_MATCH0, 0xFFFFFFFF); + rtc_writel(rtc, LPC32XX_RTC_INTSTAT, LPC32XX_RTC_MATCH0_INT_STS); + + spin_unlock(&rtc->lock); + + rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF); + + return IRQ_HANDLED; +} + +static const struct rtc_class_ops lpc32xx_rtc_ops = { + .read_time = lpc32xx_rtc_read_time, + .set_mmss = lpc32xx_rtc_set_mmss, + .read_alarm = lpc32xx_rtc_read_alarm, + .set_alarm = lpc32xx_rtc_set_alarm, + .alarm_irq_enable = lpc32xx_rtc_alarm_irq_enable, +}; + +static int __devinit lpc32xx_rtc_probe(struct platform_device *pdev) +{ + struct resource *res; + struct lpc32xx_rtc *rtc; + resource_size_t size; + int rtcirq; + u32 tmp; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(&pdev->dev, "Can't get memory resource\n"); + return -ENOENT; + } + + rtcirq = platform_get_irq(pdev, 0); + if (rtcirq < 0 || rtcirq >= NR_IRQS) { + dev_warn(&pdev->dev, "Can't get interrupt resource\n"); + rtcirq = -1; + } + + rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); + if (unlikely(!rtc)) { + dev_err(&pdev->dev, "Can't allocate memory\n"); + return -ENOMEM; + } + rtc->irq = rtcirq; + + size = resource_size(res); + + if (!devm_request_mem_region(&pdev->dev, res->start, size, + pdev->name)) { + dev_err(&pdev->dev, "RTC registers are not free\n"); + return -EBUSY; + } + + rtc->rtc_base = devm_ioremap(&pdev->dev, res->start, size); + if (!rtc->rtc_base) { + dev_err(&pdev->dev, "Can't map memory\n"); + return -ENOMEM; + } + + spin_lock_init(&rtc->lock); + + /* + * The RTC is on a seperate power domain and can keep it's state + * across a chip power cycle. If the RTC has never been previously + * setup, then set it up now for the first time. + */ + tmp = rtc_readl(rtc, LPC32XX_RTC_CTRL); + if (rtc_readl(rtc, LPC32XX_RTC_KEY) == LPC32XX_RTC_KEY_ONSW_LOADVAL) { + tmp &= ~(LPC32XX_RTC_SW_RESET | LPC32XX_RTC_CNTR_DIS | + LPC32XX_RTC_MATCH0_EN | LPC32XX_RTC_MATCH1_EN | + LPC32XX_RTC_ONSW_MATCH0_EN | + LPC32XX_RTC_ONSW_MATCH1_EN | + LPC32XX_RTC_ONSW_FORCE_HIGH); + rtc_writel(rtc, LPC32XX_RTC_CTRL, tmp); + + /* Clear latched interrupt states */ + rtc_writel(rtc, LPC32XX_RTC_MATCH0, 0xFFFFFFFF); + rtc_writel(rtc, LPC32XX_RTC_INTSTAT, + LPC32XX_RTC_MATCH0_INT_STS | + LPC32XX_RTC_MATCH1_INT_STS | + LPC32XX_RTC_ONSW_INT_STS); + + /* Write key value to RTC so it won't reload on reset */ + rtc_writel(rtc, LPC32XX_RTC_KEY, + LPC32XX_RTC_KEY_ONSW_LOADVAL); + } else { + rtc_writel(rtc, LPC32XX_RTC_CTRL, + tmp & ~LPC32XX_RTC_ONSW_MATCH0_EN); + } + + platform_set_drvdata(pdev, rtc); + + rtc->rtc = rtc_device_register(RTC_NAME, &pdev->dev, &lpc32xx_rtc_ops, + THIS_MODULE); + if (IS_ERR(rtc->rtc)) { + dev_err(&pdev->dev, "Can't get RTC\n"); + platform_set_drvdata(pdev, NULL); + return PTR_ERR(rtc->rtc); + } + + /* + * IRQ is enabled after device registration in case alarm IRQ + * is pending upon suspend exit. + */ + if (rtc->irq >= 0) { + if (devm_request_irq(&pdev->dev, rtc->irq, + lpc32xx_rtc_alarm_interrupt, + IRQF_DISABLED, pdev->name, rtc) < 0) { + dev_warn(&pdev->dev, "Can't request interrupt.\n"); + rtc->irq = -1; + } else { + device_init_wakeup(&pdev->dev, 1); + } + } + + return 0; +} + +static int __devexit lpc32xx_rtc_remove(struct platform_device *pdev) +{ + struct lpc32xx_rtc *rtc = platform_get_drvdata(pdev); + + if (rtc->irq >= 0) + device_init_wakeup(&pdev->dev, 0); + + platform_set_drvdata(pdev, NULL); + rtc_device_unregister(rtc->rtc); + + return 0; +} + +#ifdef CONFIG_PM +static int lpc32xx_rtc_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct lpc32xx_rtc *rtc = platform_get_drvdata(pdev); + + if (rtc->irq >= 0) { + if (device_may_wakeup(&pdev->dev)) + enable_irq_wake(rtc->irq); + else + disable_irq_wake(rtc->irq); + } + + return 0; +} + +static int lpc32xx_rtc_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct lpc32xx_rtc *rtc = platform_get_drvdata(pdev); + + if (rtc->irq >= 0 && device_may_wakeup(&pdev->dev)) + disable_irq_wake(rtc->irq); + + return 0; +} + +/* Unconditionally disable the alarm */ +static int lpc32xx_rtc_freeze(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct lpc32xx_rtc *rtc = platform_get_drvdata(pdev); + + spin_lock_irq(&rtc->lock); + + rtc_writel(rtc, LPC32XX_RTC_CTRL, + rtc_readl(rtc, LPC32XX_RTC_CTRL) & ~LPC32XX_RTC_MATCH0_EN); + + spin_unlock_irq(&rtc->lock); + + return 0; +} + +static int lpc32xx_rtc_thaw(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct lpc32xx_rtc *rtc = platform_get_drvdata(pdev); + + if (rtc->alarm_enabled) { + spin_lock_irq(&rtc->lock); + + rtc_writel(rtc, LPC32XX_RTC_CTRL, + rtc_readl(rtc, LPC32XX_RTC_CTRL) | + LPC32XX_RTC_MATCH0_EN); + + spin_unlock_irq(&rtc->lock); + } + + return 0; +} + +static const struct dev_pm_ops lpc32xx_rtc_pm_ops = { + .suspend = lpc32xx_rtc_suspend, + .resume = lpc32xx_rtc_resume, + .freeze = lpc32xx_rtc_freeze, + .thaw = lpc32xx_rtc_thaw, + .restore = lpc32xx_rtc_resume +}; + +#define LPC32XX_RTC_PM_OPS (&lpc32xx_rtc_pm_ops) +#else +#define LPC32XX_RTC_PM_OPS NULL +#endif + +static struct platform_driver lpc32xx_rtc_driver = { + .probe = lpc32xx_rtc_probe, + .remove = __devexit_p(lpc32xx_rtc_remove), + .driver = { + .name = RTC_NAME, + .owner = THIS_MODULE, + .pm = LPC32XX_RTC_PM_OPS + }, +}; + +static int __init lpc32xx_rtc_init(void) +{ + return platform_driver_register(&lpc32xx_rtc_driver); +} +module_init(lpc32xx_rtc_init); + +static void __exit lpc32xx_rtc_exit(void) +{ + platform_driver_unregister(&lpc32xx_rtc_driver); +} +module_exit(lpc32xx_rtc_exit); + +MODULE_AUTHOR("Kevin Wells