Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932081Ab0KLMx5 (ORCPT ); Fri, 12 Nov 2010 07:53:57 -0500 Received: from smtp-out-138.synserver.de ([212.40.180.138]:1081 "HELO smtp-out-138.synserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1757474Ab0KLMxz (ORCPT ); Fri, 12 Nov 2010 07:53:55 -0500 X-SynServer-TrustedSrc: 1 X-SynServer-AuthUser: lars@laprican.de X-SynServer-PPID: 8949 Message-ID: <4CDD38CE.1000902@metafoo.de> Date: Fri, 12 Nov 2010 13:53:34 +0100 From: Lars-Peter Clausen User-Agent: Mozilla-Thunderbird 2.0.0.24 (X11/20100329) MIME-Version: 1.0 To: Trilok Soni CC: linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, rtc-linux@googlegroups.com, linux-arm-msm@vger.kernel.org, Anirudh Ghayal , Alessandro Zummo Subject: Re: [RFC v1 PATCH 6/6] drivers: rtc: Add support for Qualcomm PMIC8058 RTC References: <1289393281-4459-1-git-send-email-tsoni@codeaurora.org> <1289393281-4459-7-git-send-email-tsoni@codeaurora.org> In-Reply-To: <1289393281-4459-7-git-send-email-tsoni@codeaurora.org> X-Enigmail-Version: 0.95.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 17742 Lines: 611 Trilok Soni wrote: > From: Anirudh Ghayal > > PMIC8058 is Qualcomm's power management IC. A > 32-bit RTC is housed inside this PMIC. The RTC driver > uses SSBI to communicate with the RTC module. > > Cc: Alessandro Zummo > Signed-off-by: Anirudh Ghayal > --- > drivers/rtc/Kconfig | 9 + > drivers/rtc/Makefile | 1 + > drivers/rtc/rtc-pm8058.c | 487 ++++++++++++++++++++++++++++++++++++++++ > include/linux/rtc/rtc-pm8058.h | 29 +++ > 4 files changed, 526 insertions(+), 0 deletions(-) > create mode 100644 drivers/rtc/rtc-pm8058.c > create mode 100644 include/linux/rtc/rtc-pm8058.h > > diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig > index 2883428..9f4ea00 100644 > --- a/drivers/rtc/Kconfig > +++ b/drivers/rtc/Kconfig > @@ -665,6 +665,15 @@ config RTC_DRV_NUC900 > If you say yes here you get support for the RTC subsystem of the > NUC910/NUC920 used in embedded systems. > > +config RTC_DRV_PM8058 > + tristate "Qualcomm PMIC8058 RTC" > + depends on PMIC8058 > + help > + Say Y here if you want to support the Qualcomm PMIC8058 RTC. > + > + To compile this driver as a module, choose M here: the > + module will be called pmic8058-rtc. > + > comment "on-CPU RTC drivers" > > config RTC_DRV_DAVINCI > diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile > index 4c2832d..d7a4f7d 100644 > --- a/drivers/rtc/Makefile > +++ b/drivers/rtc/Makefile > @@ -73,6 +73,7 @@ obj-$(CONFIG_RTC_DRV_PCF8563) += rtc-pcf8563.o > obj-$(CONFIG_RTC_DRV_PCF8583) += rtc-pcf8583.o > obj-$(CONFIG_RTC_DRV_PCF2123) += rtc-pcf2123.o > obj-$(CONFIG_RTC_DRV_PCF50633) += rtc-pcf50633.o > +obj-$(CONFIG_RTC_DRV_PM8058) += rtc-pm8058.o > obj-$(CONFIG_RTC_DRV_PL030) += rtc-pl030.o > obj-$(CONFIG_RTC_DRV_PL031) += rtc-pl031.o > obj-$(CONFIG_RTC_DRV_PS3) += rtc-ps3.o > diff --git a/drivers/rtc/rtc-pm8058.c b/drivers/rtc/rtc-pm8058.c > new file mode 100644 > index 0000000..9fef82d > --- /dev/null > +++ b/drivers/rtc/rtc-pm8058.c > @@ -0,0 +1,487 @@ > +/* Copyright (c) 2010, Code Aurora Forum. All rights reserved. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 and > + * only version 2 as published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * 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., 51 Franklin Street, Fifth Floor, Boston, MA > + * 02110-1301, USA. > + */ > + > +#define pr_fmt(fmt) "%s: " fmt, __func__ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +/* RTC control registers */ > +#define PM8058_RTC_CTRL 0x1E8 > +#define PM8058_RTC_ALARM_CTRL 0x1E9 > +#define PM8058_RTC_TEST 0x1F6 > + > +/* RTC register bases */ > +#define PM8058_RTC_READ_BASE 0x1EE > +#define PM8058_RTC_WRITE_BASE 0x1EA > +#define PM8058_RTC_ALARM_BASE 0x1F2 > + > +/* RTC_CTRL register bit fields */ > +#define PM8058_RTC_ENABLE BIT(7) > +#define PM8058_RTC_ALARM_ENABLE BIT(1) Are there other bits in the ctrl register which are not touch by this driver? If not you could turn the read-modify-write operations changing the ctrl register into simple writes. > + > +#define NUM_8_BIT_RTC_REGS 0x4 > + > +/** > + * struct pm8058_rtc - rtc driver internal structure > + * @rtc0 - rtc device for this driver > + * @rtc_irq - rtc irq number > + * @rtc_alarm_irq - rtc alarm irq number > + * @pm_chip - pointer to pm8058 parent structure > + */ > +struct pm8058_rtc { > + struct rtc_device *rtc0; Is there a reason for the '0'? > + int rtc_irq; > + int rtc_alarm_irq; > + struct pm8058_chip *pm_chip; > +}; > + > +static int > +pm8058_rtc_read_bytes(struct pm8058_rtc *rtc_dd, u8 *rtc_val, int base) > +{ > + int i, rc; > + > + /* Read the 32-bit register value, 8 bits at a time. */ > + for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) { > + rc = pm8058_read(rtc_dd->pm_chip, base + i, &rtc_val[i], 1); > + if (rc < 0) { > + pr_err("PM8058 read failed\n"); > + return rc; > + } > + } Hm, I don't know the hardware, but I would assume that pm8058_read(rtc_dd->pm_chip, base, rtc_val, NUM_8_BIT_RTC_REGS) should work as well. > + > + return 0; > +} > + > +static int > +pm8058_rtc_write_bytes(struct pm8058_rtc *rtc_dd, u8 *rtc_val, int base) > +{ > + int i, rc; > + > + /* Write the 32-bit register value, 8 bits at a time. */ > + for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) { > + rc = pm8058_write(rtc_dd->pm_chip, base + i, &rtc_val[i], 1); > + if (rc < 0) { > + pr_err("PM8058 read failed\n"); > + return rc; > + } > + } > + Same here > + return 0; > +} > + > +/* > + * Steps to write the RTC registers. > + * 1. Disable alarm if enabled. > + * 2. Write 0x00 to LSB. > + * 3. Write Byte[1], Byte[2], Byte[3] then Byte[0]. > + * 4. Enable alarm if disabled in step 1. > + */ > +static int > +pm8058_rtc0_set_time(struct device *dev, struct rtc_time *tm) > +{ > + int rc; > + unsigned long secs = 0; > + u8 value[4], reg = 0, alarm_enabled = 0, ctrl_reg = 0, i; > + struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev); > + > + rtc_tm_to_time(tm, &secs); > + > + value[0] = secs & 0xFF; > + value[1] = (secs >> 8) & 0xFF; > + value[2] = (secs >> 16) & 0xFF; > + value[3] = (secs >> 24) & 0xFF; > + > + pr_debug("Seconds value to be written to RTC = %lu\n", secs); > + > + /* Disable alarm before updating RTC */ > + rc = pm8058_read(rtc_dd->pm_chip, PM8058_RTC_CTRL, &ctrl_reg, 1); > + if (rc < 0) { > + pr_err("PM8058 read failed\n"); dev_err instead of pr_err. The other pr_err should also be replaced. > + return rc; > + } > + > + if (ctrl_reg & PM8058_RTC_ALARM_ENABLE) { > + alarm_enabled = 1; > + ctrl_reg &= ~PM8058_RTC_ALARM_ENABLE; > + rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_CTRL, > + &ctrl_reg, 1); > + if (rc < 0) { > + pr_err("PM8058 write failed\n"); > + return rc; > + } > + } > + > + /* Write Byte[1], Byte[2], Byte[3], Byte[0] */ > + reg = 0; > + rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_WRITE_BASE, ®, 1); > + if (rc < 0) { > + pr_err("PM8058 write failed\n"); > + return rc; > + } > + > + for (i = 1; i < NUM_8_BIT_RTC_REGS; i++) { > + rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_WRITE_BASE + i, > + &value[i], 1); > + if (rc < 0) { > + pr_err("Write to RTC registers failed\n"); > + return rc; > + } > + } > + > + rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_WRITE_BASE, > + &value[0], 1); > + if (rc < 0) { > + pr_err("PM8058 write failed\n"); > + return rc; > + } > + > + if (alarm_enabled) { > + ctrl_reg |= PM8058_RTC_ALARM_ENABLE; > + rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_CTRL, > + &ctrl_reg, 1); > + if (rc < 0) { > + pr_err("PM8058 write failed\n"); > + return rc; > + } > + } > + > + return 0; > +} > + > +static int > +pm8058_rtc0_read_time(struct device *dev, struct rtc_time *tm) > +{ > + int rc; > + u8 value[4], reg; > + unsigned long secs = 0; > + struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev); > + > + rc = pm8058_rtc_read_bytes(rtc_dd, value, PM8058_RTC_READ_BASE); > + if (rc < 0) { > + pr_err("RTC time read failed\n"); > + return rc; > + } > + > + /* > + * Read the LSB again and check if there has been a carry over. > + * If there is, redo the read operation. > + */ > + rc = pm8058_read(rtc_dd->pm_chip, PM8058_RTC_READ_BASE, ®, 1); > + if (rc < 0) { > + pr_err("PM8058 read failed\n"); > + return rc; > + } > + > + if (unlikely(reg < value[0])) { > + rc = pm8058_rtc_read_bytes(rtc_dd, value, > + PM8058_RTC_READ_BASE); > + if (rc < 0) { > + pr_err("RTC time read failed\n"); > + return rc; > + } > + } > + > + secs = value[0] | (value[1] << 8) | (value[2] << 16) | (value[3] << 24); > + > + rtc_time_to_tm(secs, tm); > + > + rc = rtc_valid_tm(tm); > + if (rc < 0) { > + pr_err("Invalid time read from PMIC8058\n"); > + return rc; > + } > + > + pr_debug("secs = %lu, h::m:s == %d::%d::%d, d/m/y = %d/%d/%d\n", > + secs, tm->tm_hour, tm->tm_min, tm->tm_sec, > + tm->tm_mday, tm->tm_mon, tm->tm_year); > + > + return 0; > +} > + > +static int > +pm8058_rtc0_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) > +{ > + int rc; > + u8 value[4], reg; > + unsigned long secs = 0; No need to initialize secs here. > + struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev); > + > + /* Check if a alarm is valid */ > + rc = rtc_valid_tm(&alarm->time); > + if (rc < 0) { > + pr_err("Alarm time invalid\n"); > + return -EINVAL; > + } The upper layer will already check if alarm->time is valid, so there is no need to check it here again. > + > + rtc_tm_to_time(&alarm->time, &secs); > + > + value[0] = secs & 0xFF; > + value[1] = (secs >> 8) & 0xFF; > + value[2] = (secs >> 16) & 0xFF; > + value[3] = (secs >> 24) & 0xFF; > + > + rc = pm8058_rtc_write_bytes(rtc_dd, value, PM8058_RTC_ALARM_BASE); > + if (rc < 0) { > + pr_err("Alarm could not be set\n"); > + return rc; > + } > + > + rc = pm8058_read(rtc_dd->pm_chip, PM8058_RTC_CTRL, ®, 1); > + if (rc < 0) { > + pr_err("PM8058 read failed\n"); > + return rc; > + } > + > + reg = (alarm->enabled) ? (reg | PM8058_RTC_ALARM_ENABLE) : > + (reg & ~PM8058_RTC_ALARM_ENABLE); > + > + rc = pm8058_write(rtc_dd->pm_chip, PM8058_RTC_CTRL, ®, 1); > + if (rc < 0) { > + pr_err("PM8058 write failed\n"); > + return rc; > + } > + > + pr_debug("Alarm Set for h:r:s=%d:%d:%d, d/m/y=%d/%d/%d\n", > + alarm->time.tm_hour, alarm->time.tm_min, > + alarm->time.tm_sec, alarm->time.tm_mday, > + alarm->time.tm_mon, alarm->time.tm_year); > + > + return 0; > +} > + > +static int > +pm8058_rtc0_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) > +{ > + int rc; > + u8 value[4], reg; > + unsigned long secs = 0; No need to initialize secs here. > + struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev); > + > + /* Check if the alarm is enabled */ > + rc = pm8058_read(rtc_dd->pm_chip, PM8058_RTC_CTRL, ®, 1); > + if (rc < 0) { > + pr_err("PM8058 read failed\n"); > + return rc; > + } > + alarm->enabled = !!(reg & PM8058_RTC_ALARM_ENABLE); > + > + rc = pm8058_rtc_read_bytes(rtc_dd, value, > + PM8058_RTC_ALARM_BASE); > + if (rc < 0) { > + pr_err("RTC alarm time read failed\n"); > + return rc; > + } > + > + secs = value[0] | (value[1] << 8) | (value[2] << 16) | (value[3] << 24); > + > + rtc_time_to_tm(secs, &alarm->time); > + > + rc = rtc_valid_tm(&alarm->time); > + if (rc < 0) { > + pr_err("Invalid time read from PMIC8058\n"); > + return rc; > + } > + > + pr_debug("Alarm set for - h:r:s=%d:%d:%d, d/m/y=%d/%d/%d\n", > + alarm->time.tm_hour, alarm->time.tm_min, > + alarm->time.tm_sec, alarm->time.tm_mday, > + alarm->time.tm_mon, alarm->time.tm_year); > + > + return 0; > +} > + > +static struct rtc_class_ops pm8058_rtc0_ops = { > + .read_time = pm8058_rtc0_read_time, > + .set_alarm = pm8058_rtc0_set_alarm, > + .read_alarm = pm8058_rtc0_read_alarm, Implementig alarm_irq_enable might be a good idea > +}; > + > +static irqreturn_t pm8058_alarm_trigger(int irq, void *dev_id) > +{ > + unsigned long events = 0; > + struct pm8058_rtc *rtc_dd = dev_id; > + > + events = RTC_IRQF | RTC_AF; > + rtc_update_irq(rtc_dd->rtc0, 1, events); just rtc_update_irq(rtc_dd->rtc0, 1, RTC_IRQF | RTC_AF); should be fine > + > + pr_debug("Alarm Triggered !!\n"); > + > + return IRQ_HANDLED; > +} > + > +static int __devinit pm8058_rtc_probe(struct platform_device *pdev) > +{ > + int rc; > + u8 reg; > + struct pm8058_rtc *rtc_dd; > + struct pm8058_chip *pm_chip; > + struct pm8058_rtc_pdata *pdata = pdev->dev.platform_data; > + > + if (pdata == NULL) { > + dev_err(&pdev->dev, "Platform data absent!\n"); > + return -ENXIO; > + } It might be a good idea to assume a default for rtc_write_enable if pdata is not set. > + > + pm_chip = platform_get_drvdata(pdev); > + if (pm_chip == NULL) { > + dev_err(&pdev->dev, "Invalid driver information!\n"); > + return -ENXIO; > + } > + > + rtc_dd = kzalloc(sizeof(*rtc_dd), GFP_KERNEL); > + if (rtc_dd == NULL) { > + dev_err(&pdev->dev, "Unable to allocate memory!\n"); > + return -ENOMEM; > + } > + > + rtc_dd->rtc_irq = platform_get_irq(pdev, 0); You don't seem to use this irq. > + rtc_dd->rtc_alarm_irq = platform_get_irq(pdev, 1); > + if (!rtc_dd->rtc_alarm_irq || !rtc_dd->rtc_irq) { > + dev_err(&pdev->dev, "RTC / Alarm IRQ resource absent!\n"); > + rc = -ENXIO; > + goto fail_rtc_enable; > + } > + > + rtc_dd->pm_chip = pm_chip; > + > + /* Check if the RTC is on, else turn it on */ > + rc = pm8058_read(pm_chip, PM8058_RTC_CTRL, ®, 1); > + if (rc < 0) { > + dev_err(&pdev->dev, "PM8058 read failed!\n"); > + goto fail_rtc_enable; > + } > + > + if (!(reg & PM8058_RTC_ENABLE)) { > + reg |= PM8058_RTC_ENABLE; > + rc = pm8058_write(pm_chip, PM8058_RTC_CTRL, ®, 1); > + if (rc < 0) { > + dev_err(&pdev->dev, "PM8058 write failed!\n"); > + goto fail_rtc_enable; > + } > + } > + > + if (pdata->rtc_write_enable == true) > + pm8058_rtc0_ops.set_time = pm8058_rtc0_set_time, > + > + /* Register the RTC device */ > + rtc_dd->rtc0 = rtc_device_register("pm8058_rtc0", &pdev->dev, > + &pm8058_rtc0_ops, THIS_MODULE); > + if (IS_ERR(rtc_dd->rtc0)) { > + dev_err(&pdev->dev, "%s: RTC registration failed (%ld)\n", > + __func__, PTR_ERR(rtc_dd->rtc0)); > + rc = PTR_ERR(rtc_dd->rtc0); > + goto fail_rtc_enable; > + } > + > + platform_set_drvdata(pdev, rtc_dd); > + > + /* Request the alarm IRQ */ > + rc = request_any_context_irq(rtc_dd->rtc_alarm_irq, > + pm8058_alarm_trigger, IRQF_TRIGGER_RISING, > + "pm8058_rtc_alarm", rtc_dd); > + if (rc < 0) { > + dev_err(&pdev->dev, "Request IRQ failed (%d)\n", rc); > + goto fail_req_irq; > + } > + > + device_init_wakeup(&pdev->dev, 1); > + > + dev_dbg(&pdev->dev, "Probe success !!\n"); > + > + return 0; > + > +fail_req_irq: > + rtc_device_unregister(rtc_dd->rtc0); > +fail_rtc_enable: > + kfree(rtc_dd); > + return rc; > +} > + > +#ifdef CONFIG_PM > +static int pm8058_rtc_resume(struct device *dev) > +{ > + struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev); > + > + if (device_may_wakeup(dev)) > + disable_irq_wake(rtc_dd->rtc_alarm_irq); > + > + return 0; > +} > + > +static int pm8058_rtc_suspend(struct device *dev) > +{ > + struct pm8058_rtc *rtc_dd = dev_get_drvdata(dev); > + > + if (device_may_wakeup(dev)) > + enable_irq_wake(rtc_dd->rtc_alarm_irq); > + > + return 0; > +} > + > +static const struct dev_pm_ops pm8058_rtc_pm_ops = { > + .suspend = pm8058_rtc_suspend, > + .resume = pm8058_rtc_resume, > +}; > +#endif > + > +static int __devexit pm8058_rtc_remove(struct platform_device *pdev) > +{ > + struct pm8058_rtc *rtc_dd = platform_get_drvdata(pdev); > + > + device_init_wakeup(&pdev->dev, 0); > + free_irq(rtc_dd->rtc_alarm_irq, rtc_dd); > + rtc_device_unregister(rtc_dd->rtc0); > + kfree(rtc_dd); > + > + return 0; > +} > + > +static struct platform_driver pm8058_rtc_driver = { > + .probe = pm8058_rtc_probe, > + .remove = __devexit_p(pm8058_rtc_remove), > + .driver = { > + .name = "pm8058-rtc", > + .owner = THIS_MODULE, > +#ifdef CONFIG_PM > + .pm = &pm8058_rtc_pm_ops, > +#endif > + }, > +}; > + > +static int __init pm8058_rtc_init(void) > +{ > + return platform_driver_register(&pm8058_rtc_driver); > +} > + > +static void __exit pm8058_rtc_exit(void) > +{ > + platform_driver_unregister(&pm8058_rtc_driver); > +} > + > +module_init(pm8058_rtc_init); > +module_exit(pm8058_rtc_exit); module_{init,exit} should go right beneath the function they are referring to > + > +MODULE_ALIAS("platform:pm8058-rtc"); > +MODULE_DESCRIPTION("PMIC8058 RTC driver"); > +MODULE_LICENSE("GPL v2"); > +MODULE_AUTHOR(Anirudh Ghayal ""); > diff --git a/include/linux/rtc/rtc-pm8058.h b/include/linux/rtc/rtc-pm8058.h > new file mode 100644 > index 0000000..51f7c0b > --- /dev/null > +++ b/include/linux/rtc/rtc-pm8058.h > @@ -0,0 +1,29 @@ > +/* Copyright (c) 2010, Code Aurora Forum. All rights reserved. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 and > + * only version 2 as published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * 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., 51 Franklin Street, Fifth Floor, Boston, MA > + * 02110-1301, USA. > + */ > + > +#ifndef __RTC_PM8058_H__ > +#define __RTC_PM8058_H__ > + > +/** > + * struct pm8058_rtc_pdata - RTC driver platform data > + * @rtc_write_enable - variable stating RTC write capability > + */ > +struct pm8058_rtc_pdata { > + bool rtc_write_enable; > +}; Is there a technical reason why changing the rtc clocks time should be disabled or is this a policy based decision? > + > +#endif /* __RTC_PM8058_H__ */ -- 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/