diff options
Diffstat (limited to 'drivers/rtc/rtc-mxc_v2.c')
| -rw-r--r-- | drivers/rtc/rtc-mxc_v2.c | 754 |
1 files changed, 754 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-mxc_v2.c b/drivers/rtc/rtc-mxc_v2.c new file mode 100644 index 000000000000..4d2317bd706d --- /dev/null +++ b/drivers/rtc/rtc-mxc_v2.c @@ -0,0 +1,754 @@ +/* + * Copyright (C) 2004-2011 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_v2.c + * @brief Real Time Clock interface + * + * This file contains Real Time Clock interface for Linux. + * + * @ingroup RTC + */ + +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/rtc.h> +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/clk.h> +#include <linux/uaccess.h> +#include <linux/io.h> +#include <linux/mxc_srtc.h> + +#define SRTC_LPSCLR_LLPSC_LSH 17 /* start bit for LSB time value */ + +#define SRTC_LPPDR_INIT 0x41736166 /* init for glitch detect */ + +#define SRTC_LPCR_SWR_LP (1 << 0) /* lp software reset */ +#define SRTC_LPCR_EN_LP (1 << 3) /* lp enable */ +#define SRTC_LPCR_WAE (1 << 4) /* lp wakeup alarm enable */ +#define SRTC_LPCR_SAE (1 << 5) /* lp security alarm enable */ +#define SRTC_LPCR_SI (1 << 6) /* lp security interrupt enable */ +#define SRTC_LPCR_ALP (1 << 7) /* lp alarm flag */ +#define SRTC_LPCR_LTC (1 << 8) /* lp lock time counter */ +#define SRTC_LPCR_LMC (1 << 9) /* lp lock monotonic counter */ +#define SRTC_LPCR_SV (1 << 10) /* lp security violation */ +#define SRTC_LPCR_NSA (1 << 11) /* lp non secure access */ +#define SRTC_LPCR_NVEIE (1 << 12) /* lp non valid state exit int en */ +#define SRTC_LPCR_IEIE (1 << 13) /* lp init state exit int enable */ +#define SRTC_LPCR_NVE (1 << 14) /* lp non valid state exit bit */ +#define SRTC_LPCR_IE (1 << 15) /* lp init state exit bit */ + +#define SRTC_LPCR_ALL_INT_EN (SRTC_LPCR_WAE | SRTC_LPCR_SAE | \ + SRTC_LPCR_SI | SRTC_LPCR_ALP | \ + SRTC_LPCR_NVEIE | SRTC_LPCR_IEIE) + +#define SRTC_LPSR_TRI (1 << 0) /* lp time read invalidate */ +#define SRTC_LPSR_PGD (1 << 1) /* lp power supply glitc detected */ +#define SRTC_LPSR_CTD (1 << 2) /* lp clock tampering detected */ +#define SRTC_LPSR_ALP (1 << 3) /* lp alarm flag */ +#define SRTC_LPSR_MR (1 << 4) /* lp monotonic counter rollover */ +#define SRTC_LPSR_TR (1 << 5) /* lp time rollover */ +#define SRTC_LPSR_EAD (1 << 6) /* lp external alarm detected */ +#define SRTC_LPSR_IT0 (1 << 7) /* lp IIM throttle */ +#define SRTC_LPSR_IT1 (1 << 8) +#define SRTC_LPSR_IT2 (1 << 9) +#define SRTC_LPSR_SM0 (1 << 10) /* lp security mode */ +#define SRTC_LPSR_SM1 (1 << 11) +#define SRTC_LPSR_STATE_LP0 (1 << 12) /* lp state */ +#define SRTC_LPSR_STATE_LP1 (1 << 13) +#define SRTC_LPSR_NVES (1 << 14) /* lp non-valid state exit status */ +#define SRTC_LPSR_IES (1 << 15) /* lp init state exit status */ + +#define MAX_PIE_NUM 15 +#define MAX_PIE_FREQ 32768 +#define MIN_PIE_FREQ 1 + +#define SRTC_PI0 (1 << 0) +#define SRTC_PI1 (1 << 1) +#define SRTC_PI2 (1 << 2) +#define SRTC_PI3 (1 << 3) +#define SRTC_PI4 (1 << 4) +#define SRTC_PI5 (1 << 5) +#define SRTC_PI6 (1 << 6) +#define SRTC_PI7 (1 << 7) +#define SRTC_PI8 (1 << 8) +#define SRTC_PI9 (1 << 9) +#define SRTC_PI10 (1 << 10) +#define SRTC_PI11 (1 << 11) +#define SRTC_PI12 (1 << 12) +#define SRTC_PI13 (1 << 13) +#define SRTC_PI14 (1 << 14) +#define SRTC_PI15 (1 << 15) + +#define PIT_ALL_ON (SRTC_PI1 | SRTC_PI2 | SRTC_PI3 | \ + SRTC_PI4 | SRTC_PI5 | SRTC_PI6 | SRTC_PI7 | \ + SRTC_PI8 | SRTC_PI9 | SRTC_PI10 | SRTC_PI11 | \ + SRTC_PI12 | SRTC_PI13 | SRTC_PI14 | SRTC_PI15) + +#define SRTC_SWR_HP (1 << 0) /* hp software reset */ +#define SRTC_EN_HP (1 << 3) /* hp enable */ +#define SRTC_TS (1 << 4) /* time syncronize hp with lp */ + +#define SRTC_IE_AHP (1 << 16) /* Alarm HP Interrupt Enable bit */ +#define SRTC_IE_WDHP (1 << 18) /* Write Done HP Interrupt Enable bit */ +#define SRTC_IE_WDLP (1 << 19) /* Write Done LP Interrupt Enable bit */ + +#define SRTC_ISR_AHP (1 << 16) /* interrupt status: alarm hp */ +#define SRTC_ISR_WDHP (1 << 18) /* interrupt status: write done hp */ +#define SRTC_ISR_WDLP (1 << 19) /* interrupt status: write done lp */ +#define SRTC_ISR_WPHP (1 << 20) /* interrupt status: write pending hp */ +#define SRTC_ISR_WPLP (1 << 21) /* interrupt status: write pending lp */ + +#define SRTC_LPSCMR 0x00 /* LP Secure Counter MSB Reg */ +#define SRTC_LPSCLR 0x04 /* LP Secure Counter LSB Reg */ +#define SRTC_LPSAR 0x08 /* LP Secure Alarm Reg */ +#define SRTC_LPSMCR 0x0C /* LP Secure Monotonic Counter Reg */ +#define SRTC_LPCR 0x10 /* LP Control Reg */ +#define SRTC_LPSR 0x14 /* LP Status Reg */ +#define SRTC_LPPDR 0x18 /* LP Power Supply Glitch Detector Reg */ +#define SRTC_LPGR 0x1C /* LP General Purpose Reg */ +#define SRTC_HPCMR 0x20 /* HP Counter MSB Reg */ +#define SRTC_HPCLR 0x24 /* HP Counter LSB Reg */ +#define SRTC_HPAMR 0x28 /* HP Alarm MSB Reg */ +#define SRTC_HPALR 0x2C /* HP Alarm LSB Reg */ +#define SRTC_HPCR 0x30 /* HP Control Reg */ +#define SRTC_HPISR 0x34 /* HP Interrupt Status Reg */ +#define SRTC_HPIENR 0x38 /* HP Interrupt Enable Reg */ + +#define SRTC_SECMODE_MASK 0x3 /* the mask of SRTC security mode */ +#define SRTC_SECMODE_LOW 0x0 /* Low Security */ +#define SRTC_SECMODE_MED 0x1 /* Medium Security */ +#define SRTC_SECMODE_HIGH 0x2 /* High Security */ +#define SRTC_SECMODE_RESERVED 0x3 /* Reserved */ + +struct rtc_drv_data { + struct rtc_device *rtc; + void __iomem *ioaddr; + unsigned long baseaddr; + int irq; + struct clk *clk; + bool irq_enable; +}; + + +/* completion event for implementing RTC_WAIT_FOR_TIME_SET ioctl */ +DECLARE_COMPLETION(srtc_completion); +/* global to save difference of 47-bit counter value */ +static int64_t time_diff; + +/*! + * @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 + */ + +static unsigned long rtc_status; + +static DEFINE_SPINLOCK(rtc_lock); + +/*! + * This function does write synchronization for writes to the lp srtc block. + * To take care of the asynchronous CKIL clock, all writes from the IP domain + * will be synchronized to the CKIL domain. + */ +static inline void rtc_write_sync_lp(void __iomem *ioaddr) +{ + unsigned int i, count; + /* Wait for 3 CKIL cycles */ + for (i = 0; i < 3; i++) { + count = __raw_readl(ioaddr + SRTC_LPSCLR); + while + ((__raw_readl(ioaddr + SRTC_LPSCLR)) == count); + } +} + +/*! + * 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_drv_data *pdata = dev_get_drvdata(dev); + void __iomem *ioaddr = pdata->ioaddr; + struct rtc_time alarm_tm, now_tm; + unsigned long now, time; + int ret; + + now = __raw_readl(ioaddr + SRTC_LPSCMR); + 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); + + __raw_writel(time, ioaddr + SRTC_LPSAR); + + /* clear alarm interrupt status bit */ + __raw_writel(SRTC_LPSR_ALP, ioaddr + SRTC_LPSR); + + 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_drv_data *pdata = platform_get_drvdata(pdev); + void __iomem *ioaddr = pdata->ioaddr; + u32 lp_status, lp_cr; + u32 events = 0; + + lp_status = __raw_readl(ioaddr + SRTC_LPSR); + lp_cr = __raw_readl(ioaddr + SRTC_LPCR); + + /* update irq data & counter */ + if (lp_status & SRTC_LPSR_ALP) { + if (lp_cr & SRTC_LPCR_ALP) + events |= (RTC_AF | RTC_IRQF); + + /* disable further lp alarm interrupts */ + lp_cr &= ~(SRTC_LPCR_ALP | SRTC_LPCR_WAE); + } + + /* Update interrupt enables */ + __raw_writel(lp_cr, ioaddr + SRTC_LPCR); + + /* If no interrupts are enabled, turn off interrupts in kernel */ + if (((lp_cr & SRTC_LPCR_ALL_INT_EN) == 0) && (pdata->irq_enable)) { + disable_irq_nosync(pdata->irq); + pdata->irq_enable = false; + } + + /* clear interrupt status */ + __raw_writel(lp_status, ioaddr + SRTC_LPSR); + + rtc_update_irq(pdata->rtc, 1, events); + return IRQ_HANDLED; +} + +/*! + * This function is used to open the RTC driver. + * + * @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) +{ + 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 rtc_drv_data *pdata = dev_get_drvdata(dev); + void __iomem *ioaddr = pdata->ioaddr; + unsigned long lock_flags = 0; + u32 lp_cr; + u64 time_47bit; + int retVal; + + switch (cmd) { + case RTC_AIE_OFF: + spin_lock_irqsave(&rtc_lock, lock_flags); + lp_cr = __raw_readl(ioaddr + SRTC_LPCR); + lp_cr &= ~(SRTC_LPCR_ALP | SRTC_LPCR_WAE); + if (((lp_cr & SRTC_LPCR_ALL_INT_EN) == 0) + && (pdata->irq_enable)) { + disable_irq(pdata->irq); + pdata->irq_enable = false; + } + __raw_writel(lp_cr, ioaddr + SRTC_LPCR); + spin_unlock_irqrestore(&rtc_lock, lock_flags); + return 0; + + case RTC_AIE_ON: + spin_lock_irqsave(&rtc_lock, lock_flags); + if (!pdata->irq_enable) { + enable_irq(pdata->irq); + pdata->irq_enable = true; + } + lp_cr = __raw_readl(ioaddr + SRTC_LPCR); + lp_cr |= SRTC_LPCR_ALP | SRTC_LPCR_WAE; + __raw_writel(lp_cr, ioaddr + SRTC_LPCR); + spin_unlock_irqrestore(&rtc_lock, lock_flags); + return 0; + + case RTC_READ_TIME_47BIT: + time_47bit = (((u64) __raw_readl(ioaddr + SRTC_LPSCMR)) << 32 | + ((u64) __raw_readl(ioaddr + SRTC_LPSCLR))); + time_47bit >>= SRTC_LPSCLR_LLPSC_LSH; + + if (arg && copy_to_user((u64 *) arg, &time_47bit, sizeof(u64))) + return -EFAULT; + + return 0; + + /* This IOCTL to be used by processes to be notified of time changes */ + case RTC_WAIT_TIME_SET: + + /* don't block without releasing mutex first */ + mutex_unlock(&pdata->rtc->ops_lock); + + /* sleep until awakened by SRTC driver when LPSCMR is changed */ + wait_for_completion(&srtc_completion); + + /* relock mutex because rtc_dev_ioctl will unlock again */ + retVal = mutex_lock_interruptible(&pdata->rtc->ops_lock); + + /* copy the new time difference = new time - previous time + * to the user param. The difference is a signed value */ + if (arg && copy_to_user((int64_t *) arg, &time_diff, + sizeof(int64_t))) + return -EFAULT; + + return retVal; + + } + + 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) +{ + struct rtc_drv_data *pdata = dev_get_drvdata(dev); + void __iomem *ioaddr = pdata->ioaddr; + + rtc_time_to_tm(__raw_readl(ioaddr + SRTC_LPSCMR), 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) +{ + struct rtc_drv_data *pdata = dev_get_drvdata(dev); + void __iomem *ioaddr = pdata->ioaddr; + unsigned long time; + u64 old_time_47bit, new_time_47bit; + int ret; + ret = rtc_tm_to_time(tm, &time); + if (ret != 0) + return ret; + + old_time_47bit = (((u64) __raw_readl(ioaddr + SRTC_LPSCMR)) << 32 | + ((u64) __raw_readl(ioaddr + SRTC_LPSCLR))); + old_time_47bit >>= SRTC_LPSCLR_LLPSC_LSH; + + __raw_writel(time, ioaddr + SRTC_LPSCMR); + rtc_write_sync_lp(ioaddr); + + new_time_47bit = (((u64) __raw_readl(ioaddr + SRTC_LPSCMR)) << 32 | + ((u64) __raw_readl(ioaddr + SRTC_LPSCLR))); + new_time_47bit >>= SRTC_LPSCLR_LLPSC_LSH; + + /* update the difference between previous time and new time */ + time_diff = new_time_47bit - old_time_47bit; + + /* signal all waiting threads that time changed */ + complete_all(&srtc_completion); + + /* allow signalled threads to handle the time change notification */ + schedule(); + + /* reinitialize completion variable */ + INIT_COMPLETION(srtc_completion); + + return 0; +} + +/*! + * 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 rtc_drv_data *pdata = dev_get_drvdata(dev); + void __iomem *ioaddr = pdata->ioaddr; + + rtc_time_to_tm(__raw_readl(ioaddr + SRTC_LPSAR), &alrm->time); + alrm->pending = + ((__raw_readl(ioaddr + SRTC_LPSR) & SRTC_LPSR_ALP) != 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 rtc_drv_data *pdata = dev_get_drvdata(dev); + void __iomem *ioaddr = pdata->ioaddr; + unsigned long lock_flags = 0; + u32 lp_cr; + int ret; + + if (rtc_valid_tm(&alrm->time)) { + if (alrm->time.tm_sec > 59 || + alrm->time.tm_hour > 23 || alrm->time.tm_min > 59) { + return -EINVAL; + } + } + + spin_lock_irqsave(&rtc_lock, lock_flags); + lp_cr = __raw_readl(ioaddr + SRTC_LPCR); + + ret = rtc_update_alarm(dev, &alrm->time); + if (ret) + goto out; + + if (alrm->enabled) + lp_cr |= (SRTC_LPCR_ALP | SRTC_LPCR_WAE); + else + lp_cr &= ~(SRTC_LPCR_ALP | SRTC_LPCR_WAE); + + if (lp_cr & SRTC_LPCR_ALL_INT_EN) { + if (!pdata->irq_enable) { + enable_irq(pdata->irq); + pdata->irq_enable = true; + } + } else { + if (pdata->irq_enable) { + disable_irq(pdata->irq); + pdata->irq_enable = false; + } + } + + __raw_writel(lp_cr, ioaddr + SRTC_LPCR); + +out: + spin_unlock_irqrestore(&rtc_lock, lock_flags); + rtc_write_sync_lp(ioaddr); + return ret; +} + +/*! + * This function is used to provide the content for the /proc/driver/rtc + * file. + * + * @param seq 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 *seq) +{ + struct rtc_drv_data *pdata = dev_get_drvdata(dev); + void __iomem *ioaddr = pdata->ioaddr; + + seq_printf(seq, "alarm_IRQ\t: %s\n", + (((__raw_readl(ioaddr + SRTC_LPCR)) & SRTC_LPCR_ALP) != + 0) ? "yes" : "no"); + + return 0; +} + +/*! + * 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 int mxc_rtc_probe(struct platform_device *pdev) +{ + struct clk *clk; + struct timespec tv; + struct resource *res; + struct rtc_device *rtc; + struct rtc_drv_data *pdata = NULL; + void __iomem *ioaddr; + 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 = ioremap(pdata->baseaddr, 0x40); + ioaddr = pdata->ioaddr; + + /* 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; + } else { + disable_irq(pdata->irq); + pdata->irq_enable = false; + } + } + + clk = clk_get(&pdev->dev, "rtc_clk"); + if (clk_get_rate(clk) != 32768) { + printk(KERN_ALERT "rtc clock is not valid"); + ret = -EINVAL; + clk_put(clk); + goto err_out; + } + clk_put(clk); + + /* initialize glitch detect */ + __raw_writel(SRTC_LPPDR_INIT, ioaddr + SRTC_LPPDR); + udelay(100); + + /* clear lp interrupt status */ + __raw_writel(0xFFFFFFFF, ioaddr + SRTC_LPSR); + udelay(100); + + /* move out of init state */ + __raw_writel((SRTC_LPCR_IE | SRTC_LPCR_NSA), + ioaddr + SRTC_LPCR); + + udelay(100); + + while ((__raw_readl(ioaddr + SRTC_LPSR) & SRTC_LPSR_IES) == 0) + ; + + /* move out of non-valid state */ + __raw_writel((SRTC_LPCR_IE | SRTC_LPCR_NVE | SRTC_LPCR_NSA | + SRTC_LPCR_EN_LP), ioaddr + SRTC_LPCR); + + udelay(100); + + while ((__raw_readl(ioaddr + SRTC_LPSR) & SRTC_LPSR_NVES) == 0) + ; + + __raw_writel(0xFFFFFFFF, ioaddr + SRTC_LPSR); + udelay(100); + + rtc = rtc_device_register(pdev->name, &pdev->dev, + &mxc_rtc_ops, THIS_MODULE); + if (IS_ERR(rtc)) { + ret = PTR_ERR(rtc); + goto err_out; + } + + pdata->rtc = rtc; + platform_set_drvdata(pdev, pdata); + + tv.tv_nsec = 0; + tv.tv_sec = __raw_readl(ioaddr + SRTC_LPSCMR); + + /* By default, devices should wakeup if they can */ + /* So srtc is set as "should wakeup" as it can */ + device_init_wakeup(&pdev->dev, 1); + + return ret; + +err_out: + clk_disable(pdata->clk); + iounmap(ioaddr); + if (pdata->irq >= 0) + free_irq(pdata->irq, pdev); + kfree(pdata); + return ret; +} + +static int __exit mxc_rtc_remove(struct platform_device *pdev) +{ + struct rtc_drv_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); + 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 rtc_drv_data *pdata = platform_get_drvdata(pdev); + + if (device_may_wakeup(&pdev->dev)) { + enable_irq_wake(pdata->irq); + } else { + if (pdata->irq_enable) + disable_irq(pdata->irq); + } + + 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 rtc_drv_data *pdata = platform_get_drvdata(pdev); + + if (device_may_wakeup(&pdev->dev)) { + disable_irq_wake(pdata->irq); + } else { + if (pdata->irq_enable) + enable_irq(pdata->irq); + } + + 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); + +} + +module_init(mxc_rtc_init); +module_exit(mxc_rtc_exit); + +MODULE_AUTHOR("Freescale Semiconductor, Inc."); +MODULE_DESCRIPTION("Realtime Clock Driver (RTC)"); +MODULE_LICENSE("GPL"); |