From patchwork Mon Jul 23 13:42:22 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Afzal Mohammed X-Patchwork-Id: 1228011 Return-Path: X-Original-To: patchwork-davinci@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from comal.ext.ti.com (comal.ext.ti.com [198.47.26.152]) by patchwork1.kernel.org (Postfix) with ESMTP id CD6843FD4F for ; Mon, 23 Jul 2012 14:49:15 +0000 (UTC) Received: from dlelxv30.itg.ti.com ([172.17.2.17]) by comal.ext.ti.com (8.13.7/8.13.7) with ESMTP id q6NElGxr006526; Mon, 23 Jul 2012 09:47:16 -0500 Received: from DFLE72.ent.ti.com (dfle72.ent.ti.com [128.247.5.109]) by dlelxv30.itg.ti.com (8.13.8/8.13.8) with ESMTP id q6NElG5j014130; Mon, 23 Jul 2012 09:47:16 -0500 Received: from dlelxv24.itg.ti.com (172.17.1.199) by dfle72.ent.ti.com (128.247.5.109) with Microsoft SMTP Server id 14.1.323.3; Mon, 23 Jul 2012 09:47:15 -0500 Received: from linux.omap.com (dlelxs01.itg.ti.com [157.170.227.31]) by dlelxv24.itg.ti.com (8.13.8/8.13.8) with ESMTP id q6NElFdW013367; Mon, 23 Jul 2012 09:47:15 -0500 Received: from linux.omap.com (localhost [127.0.0.1]) by linux.omap.com (Postfix) with ESMTP id F2B2F8062E; Mon, 23 Jul 2012 09:47:14 -0500 (CDT) X-Original-To: davinci-linux-open-source@linux.davincidsp.com Delivered-To: davinci-linux-open-source@linux.davincidsp.com Received: from dbdp20.itg.ti.com (dbdp20.itg.ti.com [172.24.170.38]) by linux.omap.com (Postfix) with ESMTP id E366880626 for ; Mon, 23 Jul 2012 08:42:24 -0500 (CDT) Received: from DBDE71.ent.ti.com (localhost [127.0.0.1]) by dbdp20.itg.ti.com (8.13.8/8.13.8) with ESMTP id q6NDgNjK005277; Mon, 23 Jul 2012 19:12:23 +0530 (IST) Received: from dbdp32.itg.ti.com (172.24.170.251) by DBDE71.ent.ti.com (172.24.170.149) with Microsoft SMTP Server id 14.1.323.3; Mon, 23 Jul 2012 19:12:23 +0530 Received: from udx0156546 (smtpvbd.itg.ti.com [172.24.170.250]) by dbdp32.itg.ti.com (8.13.8/8.13.8) with ESMTP id q6NDgNUK023523; Mon, 23 Jul 2012 19:12:23 +0530 Received: from ubnuser by udx0156546 with local (Exim 4.72) (envelope-from ) id 1StItz-0006dG-ES; Mon, 23 Jul 2012 19:12:23 +0530 From: Afzal Mohammed To: , , , , , , , , , , , , , Subject: [PATCH 1/6] rtc: omap: kicker mechanism support Date: Mon, 23 Jul 2012 19:12:22 +0530 Message-ID: X-Mailer: git-send-email 1.7.1 In-Reply-To: References: MIME-Version: 1.0 X-Mailman-Approved-At: Mon, 23 Jul 2012 09:46:16 -0500 CC: Afzal Mohammed X-BeenThere: davinci-linux-open-source@linux.davincidsp.com X-Mailman-Version: 2.1.12 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: Errors-To: davinci-linux-open-source-bounces@linux.davincidsp.com OMAP RTC IP can have kicker feature. This prevents spurious writes to register. To write to registers kicker lock has to be released. Procedure to do it as follows, 1. write to kick0 register, 0x83e70b13 2. write to kick1 register, 0x95a4f1e0 Writing value other than 0x83e70b13 to kick0 enables write locking, more details about kicker mechanism can be found in section 20.3.3.5.3 of AM335X TRM @www.ti.com/am335x Here id table information is added and is used to distinguish those that require kicker handling and the ones that doesn't need it. There are more features in the newer IP's compared to legacy ones other than kicker, which driver currently doesn't handle, supporting additional features would be easier with the addition of id table. Signed-off-by: Afzal Mohammed --- drivers/rtc/rtc-omap.c | 39 ++++++++++++++++++++++++++++++++++++++- 1 files changed, 38 insertions(+), 1 deletions(-) diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c index 0b614e3..65eda29 100644 --- a/drivers/rtc/rtc-omap.c +++ b/drivers/rtc/rtc-omap.c @@ -38,6 +38,8 @@ * the SoC). See the BOARD-SPECIFIC CUSTOMIZATION comment. */ +#define DRIVER_NAME "omap_rtc" + #define OMAP_RTC_BASE 0xfffb4800 /* RTC registers */ @@ -64,6 +66,9 @@ #define OMAP_RTC_COMP_MSB_REG 0x50 #define OMAP_RTC_OSC_REG 0x54 +#define OMAP_RTC_KICK0_R 0x6c +#define OMAP_RTC_KICK1_R 0x70 + /* OMAP_RTC_CTRL_REG bit fields: */ #define OMAP_RTC_CTRL_SPLIT (1<<7) #define OMAP_RTC_CTRL_DISABLE (1<<6) @@ -88,11 +93,19 @@ #define OMAP_RTC_INTERRUPTS_IT_ALARM (1<<3) #define OMAP_RTC_INTERRUPTS_IT_TIMER (1<<2) +/* OMAP_RTC_KICKER values */ +#define KICK0_VALUE (0x83e70b13) +#define KICK1_VALUE (0x95a4f1e0) + +#define OMAP_RTC_HAS_KICKER 0x1 + static void __iomem *rtc_base; #define rtc_read(addr) __raw_readb(rtc_base + (addr)) #define rtc_write(val, addr) __raw_writeb(val, rtc_base + (addr)) +#define rtc_writel(val, addr) writel(val, rtc_base + (addr)) + /* we rely on the rtc framework to handle locking (rtc->ops_lock), * so the only other requirement is that register accesses which @@ -285,11 +298,22 @@ static struct rtc_class_ops omap_rtc_ops = { static int omap_rtc_alarm; static int omap_rtc_timer; +static struct platform_device_id omap_rtc_devtype[] = { + { + .name = DRIVER_NAME, + }, { + .name = "am1808-rtc", + .driver_data = OMAP_RTC_HAS_KICKER, + } +}; +MODULE_DEVICE_TABLE(platform, omap_rtc_devtype); + static int __init omap_rtc_probe(struct platform_device *pdev) { struct resource *res, *mem; struct rtc_device *rtc; u8 reg, new_ctrl; + const struct platform_device_id *id_entry; omap_rtc_timer = platform_get_irq(pdev, 0); if (omap_rtc_timer <= 0) { @@ -322,6 +346,12 @@ static int __init omap_rtc_probe(struct platform_device *pdev) goto fail; } + id_entry = platform_get_device_id(pdev); + if (id_entry && (id_entry->driver_data & OMAP_RTC_HAS_KICKER)) { + rtc_writel(KICK0_VALUE, OMAP_RTC_KICK0_R); + rtc_writel(KICK1_VALUE, OMAP_RTC_KICK1_R); + } + rtc = rtc_device_register(pdev->name, &pdev->dev, &omap_rtc_ops, THIS_MODULE); if (IS_ERR(rtc)) { @@ -398,6 +428,8 @@ fail2: fail1: rtc_device_unregister(rtc); fail0: + if (id_entry && (id_entry->driver_data & OMAP_RTC_HAS_KICKER)) + rtc_writel(0, OMAP_RTC_KICK0_R); iounmap(rtc_base); fail: release_mem_region(mem->start, resource_size(mem)); @@ -408,6 +440,8 @@ static int __exit omap_rtc_remove(struct platform_device *pdev) { struct rtc_device *rtc = platform_get_drvdata(pdev); struct resource *mem = dev_get_drvdata(&rtc->dev); + const struct platform_device_id *id_entry = + platform_get_device_id(pdev); device_init_wakeup(&pdev->dev, 0); @@ -420,6 +454,8 @@ static int __exit omap_rtc_remove(struct platform_device *pdev) free_irq(omap_rtc_alarm, rtc); rtc_device_unregister(rtc); + if (id_entry && (id_entry->driver_data & OMAP_RTC_HAS_KICKER)) + rtc_writel(0, OMAP_RTC_KICK0_R); iounmap(rtc_base); release_mem_region(mem->start, resource_size(mem)); return 0; @@ -471,9 +507,10 @@ static struct platform_driver omap_rtc_driver = { .resume = omap_rtc_resume, .shutdown = omap_rtc_shutdown, .driver = { - .name = "omap_rtc", + .name = DRIVER_NAME, .owner = THIS_MODULE, }, + .id_table = omap_rtc_devtype, }; static int __init rtc_init(void)