/* * TX4939 internal RTC driver * Based on RBTX49xx patch from CELF patch archive. * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * (C) Copyright TOSHIBA CORPORATION 2005-2007 */ #include <linux/rtc.h> #include <linux/platform_device.h> #include <linux/interrupt.h> #include <linux/module.h> #include <linux/io.h> #include <linux/gfp.h> #include <asm/txx9/tx4939.h> struct tx4939rtc_plat_data { struct rtc_device *rtc; struct tx4939_rtc_reg __iomem *rtcreg; spinlock_t lock; }; static struct tx4939rtc_plat_data *get_tx4939rtc_plat_data(struct device *dev) { return platform_get_drvdata(to_platform_device(dev)); } static int tx4939_rtc_cmd(struct tx4939_rtc_reg __iomem *rtcreg, int cmd) { int i = 0; __raw_writel(cmd, &rtcreg->ctl); /* This might take 30us (next 32.768KHz clock) */ while (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_BUSY) { /* timeout on approx. 100us (@ GBUS200MHz) */ if (i++ > 200 * 100) return -EBUSY; cpu_relax(); } return 0; } static int tx4939_rtc_set_mmss(struct device *dev, unsigned long secs) { struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev); struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg; int i, ret; unsigned char buf[6]; buf[0] = 0; buf[1] = 0; buf[2] = secs; buf[3] = secs >> 8; buf[4] = secs >> 16; buf[5] = secs >> 24; spin_lock_irq(&pdata->lock); __raw_writel(0, &rtcreg->adr); for (i = 0; i < 6; i++) __raw_writel(buf[i], &rtcreg->dat); ret = tx4939_rtc_cmd(rtcreg, TX4939_RTCCTL_COMMAND_SETTIME | (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALME)); spin_unlock_irq(&pdata->lock); return ret; } static int tx4939_rtc_read_time(struct device *dev, struct rtc_time *tm) { struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev); struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg; int i, ret; unsigned long sec; unsigned char buf[6]; spin_lock_irq(&pdata->lock); ret = tx4939_rtc_cmd(rtcreg, TX4939_RTCCTL_COMMAND_GETTIME | (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALME)); if (ret) { spin_unlock_irq(&pdata->lock); return ret; } __raw_writel(2, &rtcreg->adr); for (i = 2; i < 6; i++) buf[i] = __raw_readl(&rtcreg->dat); spin_unlock_irq(&pdata->lock); sec = (buf[5] << 24) | (buf[4] << 16) | (buf[3] << 8) | buf[2]; rtc_time_to_tm(sec, tm); return rtc_valid_tm(tm); } static int tx4939_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) { struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev); struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg; int i, ret; unsigned long sec; unsigned char buf[6]; if (alrm->time.tm_sec < 0 || alrm->time.tm_min < 0 || alrm->time.tm_hour < 0 || alrm->time.tm_mday < 0 || alrm->time.tm_mon < 0 || alrm->time.tm_year < 0) return -EINVAL; rtc_tm_to_time(&alrm->time, &sec); buf[0] = 0; buf[1] = 0; buf[2] = sec; buf[3] = sec >> 8; buf[4] = sec >> 16; buf[5] = sec >> 24; spin_lock_irq(&pdata->lock); __raw_writel(0, &rtcreg->adr); for (i = 0; i < 6; i++) __raw_writel(buf[i], &rtcreg->dat); ret = tx4939_rtc_cmd(rtcreg, TX4939_RTCCTL_COMMAND_SETALARM | (alrm->enabled ? TX4939_RTCCTL_ALME : 0)); spin_unlock_irq(&pdata->lock); return ret; } static int tx4939_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) { struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev); struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg; int i, ret; unsigned long sec; unsigned char buf[6]; u32 ctl; spin_lock_irq(&pdata->lock); ret = tx4939_rtc_cmd(rtcreg, TX4939_RTCCTL_COMMAND_GETALARM | (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALME)); if (ret) { spin_unlock_irq(&pdata->lock); return ret; } __raw_writel(2, &rtcreg->adr); for (i = 2; i < 6; i++) buf[i] = __raw_readl(&rtcreg->dat); ctl = __raw_readl(&rtcreg->ctl); alrm->enabled = (ctl & TX4939_RTCCTL_ALME) ? 1 : 0; alrm->pending = (ctl & TX4939_RTCCTL_ALMD) ? 1 : 0; spin_unlock_irq(&pdata->lock); sec = (buf[5] << 24) | (buf[4] << 16) | (buf[3] << 8) | buf[2]; rtc_time_to_tm(sec, &alrm->time); return rtc_valid_tm(&alrm->time); } static int tx4939_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) { struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev); spin_lock_irq(&pdata->lock); tx4939_rtc_cmd(pdata->rtcreg, TX4939_RTCCTL_COMMAND_NOP | (enabled ? TX4939_RTCCTL_ALME : 0)); spin_unlock_irq(&pdata->lock); return 0; } static irqreturn_t tx4939_rtc_interrupt(int irq, void *dev_id) { struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev_id); struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg; unsigned long events = RTC_IRQF; spin_lock(&pdata->lock); if (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALMD) { events |= RTC_AF; tx4939_rtc_cmd(rtcreg, TX4939_RTCCTL_COMMAND_NOP); } spin_unlock(&pdata->lock); if (likely(pdata->rtc)) rtc_update_irq(pdata->rtc, 1, events); return IRQ_HANDLED; } static const struct rtc_class_ops tx4939_rtc_ops = { .read_time = tx4939_rtc_read_time, .read_alarm = tx4939_rtc_read_alarm, .set_alarm = tx4939_rtc_set_alarm, .set_mmss = tx4939_rtc_set_mmss, .alarm_irq_enable = tx4939_rtc_alarm_irq_enable, }; static ssize_t tx4939_rtc_nvram_read(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buf, loff_t pos, size_t size) { struct device *dev = container_of(kobj, struct device, kobj); struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev); struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg; ssize_t count; spin_lock_irq(&pdata->lock); for (count = 0; size > 0 && pos < TX4939_RTC_REG_RAMSIZE; count++, size--) { __raw_writel(pos++, &rtcreg->adr); *buf++ = __raw_readl(&rtcreg->dat); } spin_unlock_irq(&pdata->lock); return count; } static ssize_t tx4939_rtc_nvram_write(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buf, loff_t pos, size_t size) { struct device *dev = container_of(kobj, struct device, kobj); struct tx4939rtc_plat_data *pdata = get_tx4939rtc_plat_data(dev); struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg; ssize_t count; spin_lock_irq(&pdata->lock); for (count = 0; size > 0 && pos < TX4939_RTC_REG_RAMSIZE; count++, size--) { __raw_writel(pos++, &rtcreg->adr); __raw_writel(*buf++, &rtcreg->dat); } spin_unlock_irq(&pdata->lock); return count; } static struct bin_attribute tx4939_rtc_nvram_attr = { .attr = { .name = "nvram", .mode = S_IRUGO | S_IWUSR, }, .size = TX4939_RTC_REG_RAMSIZE, .read = tx4939_rtc_nvram_read, .write = tx4939_rtc_nvram_write, }; static int __init tx4939_rtc_probe(struct platform_device *pdev) { struct rtc_device *rtc; struct tx4939rtc_plat_data *pdata; struct resource *res; int irq, ret; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) return -ENODEV; irq = platform_get_irq(pdev, 0); if (irq < 0) return -ENODEV; pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); if (!pdata) return -ENOMEM; platform_set_drvdata(pdev, pdata); if (!devm_request_mem_region(&pdev->dev, res->start, resource_size(res), pdev->name)) return -EBUSY; pdata->rtcreg = devm_ioremap(&pdev->dev, res->start, resource_size(res)); if (!pdata->rtcreg) return -EBUSY; spin_lock_init(&pdata->lock); tx4939_rtc_cmd(pdata->rtcreg, TX4939_RTCCTL_COMMAND_NOP); if (devm_request_irq(&pdev->dev, irq, tx4939_rtc_interrupt, IRQF_DISABLED, pdev->name, &pdev->dev) < 0) return -EBUSY; rtc = rtc_device_register(pdev->name, &pdev->dev, &tx4939_rtc_ops, THIS_MODULE); if (IS_ERR(rtc)) return PTR_ERR(rtc); pdata->rtc = rtc; ret = sysfs_create_bin_file(&pdev->dev.kobj, &tx4939_rtc_nvram_attr); if (ret) rtc_device_unregister(rtc); return ret; } static int __exit tx4939_rtc_remove(struct platform_device *pdev) { struct tx4939rtc_plat_data *pdata = platform_get_drvdata(pdev); sysfs_remove_bin_file(&pdev->dev.kobj, &tx4939_rtc_nvram_attr); rtc_device_unregister(pdata->rtc); spin_lock_irq(&pdata->lock); tx4939_rtc_cmd(pdata->rtcreg, TX4939_RTCCTL_COMMAND_NOP); spin_unlock_irq(&pdata->lock); return 0; } static struct platform_driver tx4939_rtc_driver = { .remove = __exit_p(tx4939_rtc_remove), .driver = { .name = "tx4939rtc", .owner = THIS_MODULE, }, }; static int __init tx4939rtc_init(void) { return platform_driver_probe(&tx4939_rtc_driver, tx4939_rtc_probe); } static void __exit tx4939rtc_exit(void) { platform_driver_unregister(&tx4939_rtc_driver); } module_init(tx4939rtc_init); module_exit(tx4939rtc_exit); MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>"); MODULE_DESCRIPTION("TX4939 internal RTC driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:tx4939rtc");