Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752626AbaJ0Wkd (ORCPT ); Mon, 27 Oct 2014 18:40:33 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:40989 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752521AbaJ0Wkb (ORCPT ); Mon, 27 Oct 2014 18:40:31 -0400 Date: Mon, 27 Oct 2014 15:40:31 -0700 From: Andrew Morton To: Johan Hovold Cc: Alessandro Zummo , Tony Lindgren , =?ISO-8859-1?Q?Beno=EEt?= Cousson , Felipe Balbi , Lokesh Vutla , Guenter Roeck , nsekhar@ti.com, t-kristo@ti.com, j-keerthy@ti.com, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, rtc-linux@googlegroups.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3] rtc: omap: add support for pmic_power_en Message-Id: <20141027154031.4492ea11d401045ca04a3ff8@linux-foundation.org> In-Reply-To: <1414397368-26480-1-git-send-email-johan@kernel.org> References: <1413913086-12730-1-git-send-email-johan@kernel.org> <1414397368-26480-1-git-send-email-johan@kernel.org> X-Mailer: Sylpheed 3.2.0beta5 (GTK+ 2.24.10; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 27 Oct 2014 09:09:28 +0100 Johan Hovold wrote: > Add new property "ti,system-power-controller" to register the RTC as a > power-off handler. > > Some RTC IP revisions can control an external PMIC via the pmic_power_en > pin, which can be configured to transition to OFF on ALARM2 events and > back to ON on subsequent ALARM (wakealarm) events. > > This is based on earlier work by Colin Foe-Parker and AnilKumar Ch. [1] > > [1] https://www.mail-archive.com/linux-omap@vger.kernel.org/msg82127.html > > Tested-by: Felipe Balbi > Signed-off-by: Johan Hovold > --- > > Changes since v2: > - add two-second delay to allow alarm to trigger before returning hmpf. As this sentence is below the ^--- it doesn't get into the changelog. > ... > > +static void omap_rtc_power_off(void) > +{ > + struct omap_rtc *rtc = omap_rtc_power_off_rtc; > + struct rtc_time tm; > + unsigned long now; > + u32 val; > + > + /* enable pmic_power_en control */ > + val = rtc_readl(rtc, OMAP_RTC_PMIC_REG); > + rtc_writel(rtc, OMAP_RTC_PMIC_REG, val | OMAP_RTC_PMIC_POWER_EN_EN); > + > + /* set alarm two seconds from now */ > + omap_rtc_read_time_raw(rtc, &tm); > + bcd2tm(&tm); > + rtc_tm_to_time(&tm, &now); > + rtc_time_to_tm(now + 2, &tm); > + > + if (tm2bcd(&tm) < 0) { > + dev_err(&rtc->rtc->dev, "power off failed\n"); > + return; > + } > + > + rtc_wait_not_busy(rtc); > + > + rtc_write(rtc, OMAP_RTC_ALARM2_SECONDS_REG, tm.tm_sec); > + rtc_write(rtc, OMAP_RTC_ALARM2_MINUTES_REG, tm.tm_min); > + rtc_write(rtc, OMAP_RTC_ALARM2_HOURS_REG, tm.tm_hour); > + rtc_write(rtc, OMAP_RTC_ALARM2_DAYS_REG, tm.tm_mday); > + rtc_write(rtc, OMAP_RTC_ALARM2_MONTHS_REG, tm.tm_mon); > + rtc_write(rtc, OMAP_RTC_ALARM2_YEARS_REG, tm.tm_year); > + > + /* > + * enable ALARM2 interrupt > + * > + * NOTE: this fails on AM3352 if rtc_write (writeb) is used > + */ > + val = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG); > + rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG, > + val | OMAP_RTC_INTERRUPTS_IT_ALARM2); > + > + mdelay(2000); And it is uncommented. How on earth is a reader to know why this is here? I can do this --- a/drivers/rtc/rtc-omap.c~rtc-omap-add-support-for-pmic_power_en-v3-fix +++ a/drivers/rtc/rtc-omap.c @@ -417,6 +417,7 @@ static void omap_rtc_power_off(void) rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG, val | OMAP_RTC_INTERRUPTS_IT_ALARM2); + /* Allow alarm to trigger before returning */ mdelay(2000); } But it doesn't explain *why* we want the alarm to trigger before returning. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/