diff options
Diffstat (limited to 'drivers/rtc/rtc-mxc.c')
| -rw-r--r-- | drivers/rtc/rtc-mxc.c | 736 |
1 files changed, 736 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-mxc.c b/drivers/rtc/rtc-mxc.c new file mode 100644 index 000000000000..00e5158ab931 --- /dev/null +++ b/drivers/rtc/rtc-mxc.c @@ -0,0 +1,736 @@ +/* + * Copyright 2004-2009 Freescale Semiconductor, Inc. All Rights Reserved. + */ + +/* + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ +/* + * Implementation based on rtc-ds1553.c + */ + +/*! + * @defgroup RTC Real Time Clock (RTC) Driver + */ +/*! + * @file rtc-mxc.c + * @brief Real Time Clock interface + * + * This file contains Real Time Clock interface for Linux. + * + * @ingroup RTC + */ + +#include <linux/rtc.h> +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/clk.h> +#include <linux/uaccess.h> + +#include <mach/hardware.h> +#define RTC_INPUT_CLK_32768HZ (0x00 << 5) +#define RTC_INPUT_CLK_32000HZ (0x01 << 5) +#define RTC_INPUT_CLK_38400HZ (0x02 << 5) + +#define RTC_SW_BIT (1 << 0) +#define RTC_ALM_BIT (1 << 2) +#define RTC_1HZ_BIT (1 << 4) +#define RTC_2HZ_BIT (1 << 7) +#define RTC_SAM0_BIT (1 << 8) +#define RTC_SAM1_BIT (1 << 9) +#define RTC_SAM2_BIT (1 << 10) +#define RTC_SAM3_BIT (1 << 11) +#define RTC_SAM4_BIT (1 << 12) +#define RTC_SAM5_BIT (1 << 13) +#define RTC_SAM6_BIT (1 << 14) +#define RTC_SAM7_BIT (1 << 15) +#define PIT_ALL_ON (RTC_2HZ_BIT | RTC_SAM0_BIT | RTC_SAM1_BIT | \ + RTC_SAM2_BIT | RTC_SAM3_BIT | RTC_SAM4_BIT | \ + RTC_SAM5_BIT | RTC_SAM6_BIT | RTC_SAM7_BIT) + +#define RTC_ENABLE_BIT (1 << 7) + +#define MAX_PIE_NUM 9 +#define MAX_PIE_FREQ 512 +const u32 PIE_BIT_DEF[MAX_PIE_NUM][2] = { + {2, RTC_2HZ_BIT}, + {4, RTC_SAM0_BIT}, + {8, RTC_SAM1_BIT}, + {16, RTC_SAM2_BIT}, + {32, RTC_SAM3_BIT}, + {64, RTC_SAM4_BIT}, + {128, RTC_SAM5_BIT}, + {256, RTC_SAM6_BIT}, + {MAX_PIE_FREQ, RTC_SAM7_BIT}, +}; + +/* Those are the bits from a classic RTC we want to mimic */ +#define RTC_IRQF 0x80 /* any of the following 3 is active */ +#define RTC_PF 0x40 /* Periodic interrupt */ +#define RTC_AF 0x20 /* Alarm interrupt */ +#define RTC_UF 0x10 /* Update interrupt for 1Hz RTC */ + +#define MXC_RTC_TIME 0 +#define MXC_RTC_ALARM 1 + +#define RTC_HOURMIN 0x00 /* 32bit rtc hour/min counter reg */ +#define RTC_SECOND 0x04 /* 32bit rtc seconds counter reg */ +#define RTC_ALRM_HM 0x08 /* 32bit rtc alarm hour/min reg */ +#define RTC_ALRM_SEC 0x0C /* 32bit rtc alarm seconds reg */ +#define RTC_RTCCTL 0x10 /* 32bit rtc control reg */ +#define RTC_RTCISR 0x14 /* 32bit rtc interrupt status reg */ +#define RTC_RTCIENR 0x18 /* 32bit rtc interrupt enable reg */ +#define RTC_STPWCH 0x1C /* 32bit rtc stopwatch min reg */ +#define RTC_DAYR 0x20 /* 32bit rtc days counter reg */ +#define RTC_DAYALARM 0x24 /* 32bit rtc day alarm reg */ +#define RTC_TEST1 0x28 /* 32bit rtc test reg 1 */ +#define RTC_TEST2 0x2C /* 32bit rtc test reg 2 */ +#define RTC_TEST3 0x30 /* 32bit rtc test reg 3 */ + +struct rtc_plat_data { + struct rtc_device *rtc; + void __iomem *ioaddr; + unsigned long baseaddr; + int irq; + struct clk *clk; + unsigned int irqen; + int alrm_sec; + int alrm_min; + int alrm_hour; + int alrm_mday; +}; + +/*! + * @defgroup RTC Real Time Clock (RTC) Driver + */ +/*! + * @file rtc-mxc.c + * @brief Real Time Clock interface + * + * This file contains Real Time Clock interface for Linux. + * + * @ingroup RTC + */ + +#define RTC_VERSION "1.0" +#define MXC_EXTERNAL_RTC_OK 0 +#define MXC_EXTERNAL_RTC_ERR -1 +#define MXC_EXTERNAL_RTC_NONE -2 + +static u32 rtc_freq = 2; /* minimun value for PIE */ +static unsigned long rtc_status; + +static struct rtc_time g_rtc_alarm = { + .tm_year = 0, + .tm_mon = 0, + .tm_mday = 0, + .tm_hour = 0, + .tm_mon = 0, + .tm_sec = 0, +}; + +static DEFINE_SPINLOCK(rtc_lock); + +/*! + * This function is used to obtain the RTC time or the alarm value in + * second. + * + * @param time_alarm use MXC_RTC_TIME for RTC time value; MXC_RTC_ALARM for alarm value + * + * @return The RTC time or alarm time in second. + */ +static u32 get_alarm_or_time(struct device *dev, int time_alarm) +{ + struct platform_device *pdev = to_platform_device(dev); + struct rtc_plat_data *pdata = platform_get_drvdata(pdev); + void __iomem *ioaddr = pdata->ioaddr; + u32 day, hr, min, sec, hr_min; + if (time_alarm == MXC_RTC_TIME) { + day = readw(ioaddr + RTC_DAYR); + hr_min = readw(ioaddr + RTC_HOURMIN); + sec = readw(ioaddr + RTC_SECOND); + } else if (time_alarm == MXC_RTC_ALARM) { + day = readw(ioaddr + RTC_DAYALARM); + hr_min = (0x0000FFFF) & readw(ioaddr + RTC_ALRM_HM); + sec = readw(ioaddr + RTC_ALRM_SEC); + } else { + panic("wrong value for time_alarm=%d\n", time_alarm); + } + + hr = hr_min >> 8; + min = hr_min & 0x00FF; + + return ((((day * 24 + hr) * 60) + min) * 60 + sec); +} + +/*! + * This function sets the RTC alarm value or the time value. + * + * @param time_alarm the new alarm value to be updated in the RTC + * @param time use MXC_RTC_TIME for RTC time value; MXC_RTC_ALARM for alarm value + */ +static void set_alarm_or_time(struct device *dev, int time_alarm, u32 time) +{ + u32 day, hr, min, sec, temp; + struct platform_device *pdev = to_platform_device(dev); + struct rtc_plat_data *pdata = platform_get_drvdata(pdev); + void __iomem *ioaddr = pdata->ioaddr; + day = time / 86400; + time -= day * 86400; + /* time is within a day now */ + hr = time / 3600; + time -= hr * 3600; + /* time is within an hour now */ + min = time / 60; + sec = time - min * 60; + + temp = (hr << 8) + min; + + if (time_alarm == MXC_RTC_TIME) { + writew(day, ioaddr + RTC_DAYR); + writew(sec, ioaddr + RTC_SECOND); + writew(temp, ioaddr + RTC_HOURMIN); + } else if (time_alarm == MXC_RTC_ALARM) { + writew(day, ioaddr + RTC_DAYALARM); + writew(sec, ioaddr + RTC_ALRM_SEC); + writew(temp, ioaddr + RTC_ALRM_HM); + } else { + panic("wrong value for time_alarm=%d\n", time_alarm); + } +} + +/*! + * This function updates the RTC alarm registers and then clears all the + * interrupt status bits. + * + * @param alrm the new alarm value to be updated in the RTC + * + * @return 0 if successful; non-zero otherwise. + */ +static int rtc_update_alarm(struct device *dev, struct rtc_time *alrm) +{ + struct rtc_time alarm_tm, now_tm; + unsigned long now, time; + int ret; + struct platform_device *pdev = to_platform_device(dev); + struct rtc_plat_data *pdata = platform_get_drvdata(pdev); + void __iomem *ioaddr = pdata->ioaddr; + + now = get_alarm_or_time(dev, MXC_RTC_TIME); + rtc_time_to_tm(now, &now_tm); + alarm_tm.tm_year = now_tm.tm_year; + alarm_tm.tm_mon = now_tm.tm_mon; + alarm_tm.tm_mday = now_tm.tm_mday; + alarm_tm.tm_hour = alrm->tm_hour; + alarm_tm.tm_min = alrm->tm_min; + alarm_tm.tm_sec = alrm->tm_sec; + rtc_tm_to_time(&now_tm, &now); + rtc_tm_to_time(&alarm_tm, &time); + if (time < now) { + time += 60 * 60 * 24; + rtc_time_to_tm(time, &alarm_tm); + } + ret = rtc_tm_to_time(&alarm_tm, &time); + + /* clear all the interrupt status bits */ + writew(readw(ioaddr + RTC_RTCISR), ioaddr + RTC_RTCISR); + + set_alarm_or_time(dev, MXC_RTC_ALARM, time); + + return ret; +} + +/*! + * This function is the RTC interrupt service routine. + * + * @param irq RTC IRQ number + * @param dev_id device ID which is not used + * + * @return IRQ_HANDLED as defined in the include/linux/interrupt.h file. + */ +static irqreturn_t mxc_rtc_interrupt(int irq, void *dev_id) +{ + struct platform_device *pdev = dev_id; + struct rtc_plat_data *pdata = platform_get_drvdata(pdev); + void __iomem *ioaddr = pdata->ioaddr; + u32 status; + u32 events = 0; + spin_lock(&rtc_lock); + status = readw(ioaddr + RTC_RTCISR) & readw(ioaddr + RTC_RTCIENR); + /* clear interrupt sources */ + writew(status, ioaddr + RTC_RTCISR); + + /* clear alarm interrupt if it has occurred */ + if (status & RTC_ALM_BIT) { + status &= ~RTC_ALM_BIT; + } + + /* update irq data & counter */ + if (status & RTC_ALM_BIT) { + events |= (RTC_AF | RTC_IRQF); + } + if (status & RTC_1HZ_BIT) { + events |= (RTC_UF | RTC_IRQF); + } + if (status & PIT_ALL_ON) { + events |= (RTC_PF | RTC_IRQF); + } + + if ((status & RTC_ALM_BIT) && rtc_valid_tm(&g_rtc_alarm)) { + rtc_update_alarm(&pdev->dev, &g_rtc_alarm); + } + + spin_unlock(&rtc_lock); + rtc_update_irq(pdata->rtc, 1, events); + return IRQ_HANDLED; +} + +/*! + * This function is used to open the RTC driver by registering the RTC + * interrupt service routine. + * + * @return 0 if successful; non-zero otherwise. + */ +static int mxc_rtc_open(struct device *dev) +{ + if (test_and_set_bit(1, &rtc_status)) + return -EBUSY; + return 0; +} + +/*! + * clear all interrupts and release the IRQ + */ +static void mxc_rtc_release(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct rtc_plat_data *pdata = platform_get_drvdata(pdev); + void __iomem *ioaddr = pdata->ioaddr; + + spin_lock_irq(&rtc_lock); + writew(0, ioaddr + RTC_RTCIENR); /* Disable all rtc interrupts */ + writew(0xFFFFFFFF, ioaddr + RTC_RTCISR); /* Clear all interrupt status */ + spin_unlock_irq(&rtc_lock); + rtc_status = 0; +} + +/*! + * This function is used to support some ioctl calls directly. + * Other ioctl calls are supported indirectly through the + * arm/common/rtctime.c file. + * + * @param cmd ioctl command as defined in include/linux/rtc.h + * @param arg value for the ioctl command + * + * @return 0 if successful or negative value otherwise. + */ +static int mxc_rtc_ioctl(struct device *dev, unsigned int cmd, + unsigned long arg) +{ + struct platform_device *pdev = to_platform_device(dev); + struct rtc_plat_data *pdata = platform_get_drvdata(pdev); + void __iomem *ioaddr = pdata->ioaddr; + int i; + switch (cmd) { + case RTC_PIE_OFF: + writew((readw(ioaddr + RTC_RTCIENR) & ~PIT_ALL_ON), + ioaddr + RTC_RTCIENR); + return 0; + case RTC_IRQP_SET: + if (arg < 2 || arg > MAX_PIE_FREQ || (arg % 2) != 0) + return -EINVAL; /* Also make sure a power of 2Hz */ + if ((arg > 64) && (!capable(CAP_SYS_RESOURCE))) + return -EACCES; + rtc_freq = arg; + return 0; + case RTC_IRQP_READ: + return put_user(rtc_freq, (u32 *) arg); + case RTC_PIE_ON: + for (i = 0; i < MAX_PIE_NUM; i++) { + if (PIE_BIT_DEF[i][0] == rtc_freq) { + break; + } + } + if (i == MAX_PIE_NUM) { + return -EACCES; + } + spin_lock_irq(&rtc_lock); + writew((readw(ioaddr + RTC_RTCIENR) | PIE_BIT_DEF[i][1]), + ioaddr + RTC_RTCIENR); + spin_unlock_irq(&rtc_lock); + return 0; + case RTC_AIE_OFF: + spin_lock_irq(&rtc_lock); + writew((readw(ioaddr + RTC_RTCIENR) & ~RTC_ALM_BIT), + ioaddr + RTC_RTCIENR); + spin_unlock_irq(&rtc_lock); + return 0; + + case RTC_AIE_ON: + spin_lock_irq(&rtc_lock); + writew((readw(ioaddr + RTC_RTCIENR) | RTC_ALM_BIT), + ioaddr + RTC_RTCIENR); + spin_unlock_irq(&rtc_lock); + return 0; + + case RTC_UIE_OFF: /* UIE is for the 1Hz interrupt */ + spin_lock_irq(&rtc_lock); + writew((readw(ioaddr + RTC_RTCIENR) & ~RTC_1HZ_BIT), + ioaddr + RTC_RTCIENR); + spin_unlock_irq(&rtc_lock); + return 0; + + case RTC_UIE_ON: + spin_lock_irq(&rtc_lock); + writew((readw(ioaddr + RTC_RTCIENR) | RTC_1HZ_BIT), + ioaddr + RTC_RTCIENR); + spin_unlock_irq(&rtc_lock); + return 0; + } + return -ENOIOCTLCMD; +} + +/*! + * This function reads the current RTC time into tm in Gregorian date. + * + * @param tm contains the RTC time value upon return + * + * @return 0 if successful; non-zero otherwise. + */ +static int mxc_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + u32 val; + + /* Avoid roll-over from reading the different registers */ + do { + val = get_alarm_or_time(dev, MXC_RTC_TIME); + } while (val != get_alarm_or_time(dev, MXC_RTC_TIME)); + + rtc_time_to_tm(val, tm); + return 0; +} + +/*! + * This function sets the internal RTC time based on tm in Gregorian date. + * + * @param tm the time value to be set in the RTC + * + * @return 0 if successful; non-zero otherwise. + */ +static int mxc_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + unsigned long time; + int ret; + ret = rtc_tm_to_time(tm, &time); + if (ret != 0) { + return ret; + } + + /* Avoid roll-over from reading the different registers */ + do { + set_alarm_or_time(dev, MXC_RTC_TIME, time); + } while (time != get_alarm_or_time(dev, MXC_RTC_TIME)); + + return ret; +} + +/*! + * This function reads the current alarm value into the passed in \b alrm + * argument. It updates the \b alrm's pending field value based on the whether + * an alarm interrupt occurs or not. + * + * @param alrm contains the RTC alarm value upon return + * + * @return 0 if successful; non-zero otherwise. + */ +static int mxc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct platform_device *pdev = to_platform_device(dev); + struct rtc_plat_data *pdata = platform_get_drvdata(pdev); + void __iomem *ioaddr = pdata->ioaddr; + + rtc_time_to_tm(get_alarm_or_time(dev, MXC_RTC_ALARM), &alrm->time); + alrm->pending = + ((readw(ioaddr + RTC_RTCISR) & RTC_ALM_BIT) != 0) ? 1 : 0; + + return 0; +} + +/*! + * This function sets the RTC alarm based on passed in alrm. + * + * @param alrm the alarm value to be set in the RTC + * + * @return 0 if successful; non-zero otherwise. + */ +static int mxc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct platform_device *pdev = to_platform_device(dev); + struct rtc_plat_data *pdata = platform_get_drvdata(pdev); + void __iomem *ioaddr = pdata->ioaddr; + int ret; + + spin_lock_irq(&rtc_lock); + if (rtc_valid_tm(&alrm->time)) { + if (alrm->time.tm_sec > 59 || + alrm->time.tm_hour > 23 || alrm->time.tm_min > 59) { + ret = -EINVAL; + goto out; + } + ret = rtc_update_alarm(dev, &alrm->time); + } else { + if ((ret = rtc_valid_tm(&alrm->time))) + goto out; + ret = rtc_update_alarm(dev, &alrm->time); + } + + if (ret == 0) { + memcpy(&g_rtc_alarm, &alrm->time, sizeof(struct rtc_time)); + + if (alrm->enabled) { + writew((readw(ioaddr + RTC_RTCIENR) | RTC_ALM_BIT), + ioaddr + RTC_RTCIENR); + } else { + writew((readw(ioaddr + RTC_RTCIENR) & ~RTC_ALM_BIT), + ioaddr + RTC_RTCIENR); + } + } + out: + spin_unlock_irq(&rtc_lock); + + return ret; +} + +/*! + * This function is used to provide the content for the /proc/driver/rtc + * file. + * + * @param buf the buffer to hold the information that the driver wants to write + * + * @return The number of bytes written into the rtc file. + */ +static int mxc_rtc_proc(struct device *dev, struct seq_file *sq) +{ + struct platform_device *pdev = to_platform_device(dev); + struct rtc_plat_data *pdata = platform_get_drvdata(pdev); + void __iomem *ioaddr = pdata->ioaddr; + char *p = sq->buf; + + p += sprintf(p, "alarm_IRQ\t: %s\n", + (((readw(ioaddr + RTC_RTCIENR)) & RTC_ALM_BIT) != + 0) ? "yes" : "no"); + p += sprintf(p, "update_IRQ\t: %s\n", + (((readw(ioaddr + RTC_RTCIENR)) & RTC_1HZ_BIT) != + 0) ? "yes" : "no"); + p += sprintf(p, "periodic_IRQ\t: %s\n", + (((readw(ioaddr + RTC_RTCIENR)) & PIT_ALL_ON) != + 0) ? "yes" : "no"); + p += sprintf(p, "periodic_freq\t: %d\n", rtc_freq); + + return p - (sq->buf); +} + +/*! + * The RTC driver structure + */ +static struct rtc_class_ops mxc_rtc_ops = { + .open = mxc_rtc_open, + .release = mxc_rtc_release, + .ioctl = mxc_rtc_ioctl, + .read_time = mxc_rtc_read_time, + .set_time = mxc_rtc_set_time, + .read_alarm = mxc_rtc_read_alarm, + .set_alarm = mxc_rtc_set_alarm, + .proc = mxc_rtc_proc, +}; + +/*! MXC RTC Power management control */ + +static struct timespec mxc_rtc_delta; + +static int mxc_rtc_probe(struct platform_device *pdev) +{ + struct clk *clk; + struct timespec tv; + struct resource *res; + struct rtc_device *rtc; + struct rtc_plat_data *pdata = NULL; + u32 reg; + int ret = 0; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENODEV; + + pdata = kzalloc(sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return -ENOMEM; + + pdata->clk = clk_get(&pdev->dev, "rtc_clk"); + clk_enable(pdata->clk); + + pdata->baseaddr = res->start; + pdata->ioaddr = ((void *)(IO_ADDRESS(pdata->baseaddr))); + /* Configure and enable the RTC */ + pdata->irq = platform_get_irq(pdev, 0); + if (pdata->irq >= 0) { + if (request_irq(pdata->irq, mxc_rtc_interrupt, IRQF_SHARED, + pdev->name, pdev) < 0) { + dev_warn(&pdev->dev, "interrupt not available.\n"); + pdata->irq = -1; + } + } + rtc = + rtc_device_register(pdev->name, &pdev->dev, &mxc_rtc_ops, + THIS_MODULE); + if (IS_ERR(rtc)) { + ret = PTR_ERR(rtc); + if (pdata->irq >= 0) + free_irq(pdata->irq, pdev); + kfree(pdata); + return ret; + } + pdata->rtc = rtc; + platform_set_drvdata(pdev, pdata); + tv.tv_nsec = 0; + tv.tv_sec = get_alarm_or_time(&pdev->dev, MXC_RTC_TIME); + clk = clk_get(NULL, "ckil"); + if (clk_get_rate(clk) == 32768) + reg = RTC_INPUT_CLK_32768HZ; + else if (clk_get_rate(clk) == 32000) + reg = RTC_INPUT_CLK_32000HZ; + else if (clk_get_rate(clk) == 38400) + reg = RTC_INPUT_CLK_38400HZ; + else { + printk(KERN_ALERT "rtc clock is not valid"); + return -EINVAL; + } + clk_put(clk); + reg |= RTC_ENABLE_BIT; + writew(reg, (pdata->ioaddr + RTC_RTCCTL)); + if (((readw(pdata->ioaddr + RTC_RTCCTL)) & RTC_ENABLE_BIT) == 0) { + printk(KERN_ALERT "rtc : hardware module can't be enabled!\n"); + return -EPERM; + } + printk("Real TIme clock Driver v%s \n", RTC_VERSION); + return ret; +} + +static int __exit mxc_rtc_remove(struct platform_device *pdev) +{ + struct rtc_plat_data *pdata = platform_get_drvdata(pdev); + rtc_device_unregister(pdata->rtc); + if (pdata->irq >= 0) { + free_irq(pdata->irq, pdev); + } + clk_disable(pdata->clk); + clk_put(pdata->clk); + kfree(pdata); + mxc_rtc_release(NULL); + return 0; +} + +/*! + * This function is called to save the system time delta relative to + * the MXC RTC when enterring a low power state. This time delta is + * then used on resume to adjust the system time to account for time + * loss while suspended. + * + * @param pdev not used + * @param state Power state to enter. + * + * @return The function always returns 0. + */ +static int mxc_rtc_suspend(struct platform_device *pdev, pm_message_t state) +{ + struct timespec tv; + + /* calculate time delta for suspend */ + /* RTC precision is 1 second; adjust delta for avg 1/2 sec err */ + tv.tv_nsec = NSEC_PER_SEC >> 1; + tv.tv_sec = get_alarm_or_time(&pdev->dev, MXC_RTC_TIME); + set_normalized_timespec(&mxc_rtc_delta, + xtime.tv_sec - tv.tv_sec, + xtime.tv_nsec - tv.tv_nsec); + + return 0; +} + +/*! + * This function is called to correct the system time based on the + * current MXC RTC time relative to the time delta saved during + * suspend. + * + * @param pdev not used + * + * @return The function always returns 0. + */ +static int mxc_rtc_resume(struct platform_device *pdev) +{ + struct timespec tv; + struct timespec ts; + + tv.tv_nsec = 0; + tv.tv_sec = get_alarm_or_time(&pdev->dev, MXC_RTC_TIME); + + /* restore wall clock using delta against this RTC; + * adjust again for avg 1/2 second RTC sampling error + */ + set_normalized_timespec(&ts, + tv.tv_sec + mxc_rtc_delta.tv_sec, + (NSEC_PER_SEC >> 1) + mxc_rtc_delta.tv_nsec); + do_settimeofday(&ts); + + return 0; +} + +/*! + * Contains pointers to the power management callback functions. + */ +static struct platform_driver mxc_rtc_driver = { + .driver = { + .name = "mxc_rtc", + }, + .probe = mxc_rtc_probe, + .remove = __exit_p(mxc_rtc_remove), + .suspend = mxc_rtc_suspend, + .resume = mxc_rtc_resume, +}; + +/*! + * This function creates the /proc/driver/rtc file and registers the device RTC + * in the /dev/misc directory. It also reads the RTC value from external source + * and setup the internal RTC properly. + * + * @return -1 if RTC is failed to initialize; 0 is successful. + */ +static int __init mxc_rtc_init(void) +{ + return platform_driver_register(&mxc_rtc_driver); +} + +/*! + * This function removes the /proc/driver/rtc file and un-registers the + * device RTC from the /dev/misc directory. + */ +static void __exit mxc_rtc_exit(void) +{ + platform_driver_unregister(&mxc_rtc_driver); + +} + +device_initcall_sync(mxc_rtc_init); +module_exit(mxc_rtc_exit); + +MODULE_AUTHOR("Freescale Semiconductor, Inc."); +MODULE_DESCRIPTION("Realtime Clock Driver (RTC)"); +MODULE_LICENSE("GPL"); |