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 cd844ec..3ca26ac 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,
@@ -79,6 +81,9 @@ 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)
@@ -267,6 +272,42 @@ 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,
@@ -283,6 +324,11 @@ 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);
@@ -389,8 +435,31 @@ 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:
--
1.8.2.rc2
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