The persistent registers 1-5 are completely software defined. To have access from userspace, export them via sysfs.
Signed-off-by: Steffen Trumtrar <s.trumt...@pengutronix.de> --- drivers/rtc/rtc-stmp3xxx.c | 69 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c index 936b0ca..16b45c8 100644 --- a/drivers/rtc/rtc-stmp3xxx.c +++ b/drivers/rtc/rtc-stmp3xxx.c @@ -67,6 +67,8 @@ /* missing bitmask in headers */ #define STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER 0x80000000 +#define STMP3XXX_RTC_PERSISTENT_LEN (0xC0 - STMP3XXX_RTC_PERSISTENT1) + enum clock_source { MXS_UNKNOWN, MXS_OSC_24M, MXS_OSC_32K, MXS_OSC_32K768 }; struct stmp3xxx_rtc_data { @@ -74,6 +76,9 @@ struct stmp3xxx_rtc_data { void __iomem *io; int irq_alarm; enum clock_source clk_src; +#if IS_ENABLED(CONFIG_RTC_INTF_SYSFS) + struct bin_attribute *persist; +#endif }; #if IS_ENABLED(CONFIG_STMP3XXX_RTC_WATCHDOG) @@ -262,6 +267,42 @@ static int stmp3xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) return 0; } +#if IS_ENABLED(CONFIG_RTC_INTF_SYSFS) +static ssize_t stmp3xxx_rtc_persist_read(struct file *filep, + struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t off, size_t size) +{ + struct rtc_device *rtc = container_of(kobj, struct rtc_device, + dev.kobj); + struct device *dev = rtc->dev.parent; + struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev); + ssize_t count; + + for (count = 0; size; size--, off++, count++) + *buf++ = readl(rtc_data->io + STMP3XXX_RTC_PERSISTENT1 + off); + + return count; +} + +static ssize_t stmp3xxx_rtc_persist_write(struct file *filep, + struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t off, size_t size) +{ + struct rtc_device *rtc = container_of(kobj, struct rtc_device, + dev.kobj); + struct device *dev = rtc->dev.parent; + struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev); + ssize_t count; + + for (count = 0; size; size--, off++, count++) + writel(*buf++, rtc_data->io + STMP3XXX_RTC_PERSISTENT1 + off); + + return count; +} +#endif + static struct rtc_class_ops stmp3xxx_rtc_ops = { .alarm_irq_enable = stmp3xxx_alarm_irq_enable, @@ -278,6 +319,11 @@ static int stmp3xxx_rtc_remove(struct platform_device *pdev) if (!rtc_data) return 0; +#if IS_ENABLED(CONFIG_RTC_INTF_SYSFS) + sysfs_remove_bin_file(&pdev->dev.kobj, rtc_data->persist); + kfree(rtc_data->persist); +#endif + writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, rtc_data->io + STMP3XXX_RTC_CTRL_CLR); free_irq(rtc_data->irq_alarm, &pdev->dev); @@ -384,8 +430,31 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) } stmp3xxx_wdt_register(pdev); + +#if IS_ENABLED(CONFIG_RTC_INTF_SYSFS) + rtc_data->persist = kzalloc(sizeof(struct bin_attribute), GFP_KERNEL); + if (!rtc_data->persist) { + err = -ENOMEM; + goto out_persist; + } + + rtc_data->persist->attr.name = "persistent"; + rtc_data->persist->attr.mode = S_IRUGO | S_IWUSR; + sysfs_bin_attr_init(rtc_data->persist); + rtc_data->persist->read = stmp3xxx_rtc_persist_read; + rtc_data->persist->write = stmp3xxx_rtc_persist_write; + rtc_data->persist->size = STMP3XXX_RTC_PERSISTENT_LEN; + err = sysfs_create_bin_file(&rtc_data->rtc->dev.kobj, + rtc_data->persist); + if (err) { + kfree(rtc_data->persist); + goto out_persist; + } +#endif + return 0; +out_persist: out_irq_alarm: rtc_device_unregister(rtc_data->rtc); out_remap: -- 1.7.10.4 _______________________________________________ devicetree-discuss mailing list devicetree-discuss@lists.ozlabs.org https://lists.ozlabs.org/listinfo/devicetree-discuss