diff options
Diffstat (limited to 'drivers/rtc/rtc-tx4939.c')
| -rw-r--r-- | drivers/rtc/rtc-tx4939.c | 317 |
1 files changed, 317 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-tx4939.c b/drivers/rtc/rtc-tx4939.c new file mode 100644 index 000000000000..4ee4857ff207 --- /dev/null +++ b/drivers/rtc/rtc-tx4939.c @@ -0,0 +1,317 @@ +/* + * 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/io.h> +#include <asm/txx9/tx4939.h> + +struct tx4939rtc_plat_data { + struct rtc_device *rtc; + struct tx4939_rtc_reg __iomem *rtcreg; +}; + +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->rtc->irq_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->rtc->irq_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->rtc->irq_lock); + ret = tx4939_rtc_cmd(rtcreg, + TX4939_RTCCTL_COMMAND_GETTIME | + (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALME)); + if (ret) { + spin_unlock_irq(&pdata->rtc->irq_lock); + return ret; + } + __raw_writel(2, &rtcreg->adr); + for (i = 2; i < 6; i++) + buf[i] = __raw_readl(&rtcreg->dat); + spin_unlock_irq(&pdata->rtc->irq_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->rtc->irq_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->rtc->irq_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->rtc->irq_lock); + ret = tx4939_rtc_cmd(rtcreg, + TX4939_RTCCTL_COMMAND_GETALARM | + (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALME)); + if (ret) { + spin_unlock_irq(&pdata->rtc->irq_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->rtc->irq_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->rtc->irq_lock); + tx4939_rtc_cmd(pdata->rtcreg, + TX4939_RTCCTL_COMMAND_NOP | + (enabled ? TX4939_RTCCTL_ALME : 0)); + spin_unlock_irq(&pdata->rtc->irq_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->rtc->irq_lock); + if (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALMD) { + events |= RTC_AF; + tx4939_rtc_cmd(rtcreg, TX4939_RTCCTL_COMMAND_NOP); + } + spin_unlock(&pdata->rtc->irq_lock); + 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 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->rtc->irq_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->rtc->irq_lock); + return count; +} + +static ssize_t tx4939_rtc_nvram_write(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->rtc->irq_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->rtc->irq_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; + + tx4939_rtc_cmd(pdata->rtcreg, TX4939_RTCCTL_COMMAND_NOP); + if (devm_request_irq(&pdev->dev, irq, tx4939_rtc_interrupt, + IRQF_DISABLED | IRQF_SHARED, + 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); + struct rtc_device *rtc = pdata->rtc; + + spin_lock_irq(&rtc->irq_lock); + tx4939_rtc_cmd(pdata->rtcreg, TX4939_RTCCTL_COMMAND_NOP); + spin_unlock_irq(&rtc->irq_lock); + sysfs_remove_bin_file(&pdev->dev.kobj, &tx4939_rtc_nvram_attr); + rtc_device_unregister(rtc); + platform_set_drvdata(pdev, NULL); + 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"); |