#include "line-display.h"
+#define DEFAULT_SCROLL_RATE (HZ / 2)
+
/**
* linedisp_scroll() - scroll the display by a character
* @t: really a pointer to the private data structure
linedisp->scroll_pos %= linedisp->message_len;
/* rearm the timer */
- if (linedisp->message_len > num_chars)
+ if (linedisp->message_len > num_chars && linedisp->scroll_rate)
mod_timer(&linedisp->timer, jiffies + linedisp->scroll_rate);
}
static DEVICE_ATTR_RW(message);
+static ssize_t scroll_step_ms_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct linedisp *linedisp = container_of(dev, struct linedisp, dev);
+
+ return sysfs_emit(buf, "%u\n", jiffies_to_msecs(linedisp->scroll_rate));
+}
+
+static ssize_t scroll_step_ms_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct linedisp *linedisp = container_of(dev, struct linedisp, dev);
+ unsigned int ms;
+
+ if (kstrtouint(buf, 10, &ms) != 0)
+ return -EINVAL;
+
+ linedisp->scroll_rate = msecs_to_jiffies(ms);
+ if (linedisp->message && linedisp->message_len > linedisp->num_chars) {
+ del_timer_sync(&linedisp->timer);
+ if (linedisp->scroll_rate)
+ linedisp_scroll(&linedisp->timer);
+ }
+
+ return count;
+}
+
+static DEVICE_ATTR_RW(scroll_step_ms);
+
static struct attribute *linedisp_attrs[] = {
&dev_attr_message.attr,
+ &dev_attr_scroll_step_ms.attr,
NULL,
};
ATTRIBUTE_GROUPS(linedisp);
linedisp->update = update;
linedisp->buf = buf;
linedisp->num_chars = num_chars;
- linedisp->scroll_rate = HZ / 2;
+ linedisp->scroll_rate = DEFAULT_SCROLL_RATE;
device_initialize(&linedisp->dev);
dev_set_name(&linedisp->dev, "linedisp.%lu",