[PATCH v2 2/2] fbcon: expose cursor blink interval via sysfs

Scot Doyle
2015-01-24T17:41:50Z

five times per second. Expose this setting via
/sys/class/graphics/fbcon/cursor_blink_ms

Values written to the interface set the approximate time interval in
milliseconds between cursor toggles, from 1 to 32767. Since the interval
is stored internally as a number of jiffies, the millisecond value read
from the interface may not exactly match the entered value.

An outstanding blink timer is reset after a new value is entered.

If the cursor blink is disabled, either via the 'cursor_blink' boolean
setting or some other mechanism, the 'cursor_blink_ms' setting may still
be modified. The new value will be used if the blink is reactivated.

Tested with intelfb.

Signed-off-by: Scot Doyle <lkml14@scotdoyle.com>
---
v2: Use kstrtos16() instead of kstrtoul() and min_t(). Thanks Geert!

drivers/video/console/fbcon.c | 73 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 73 insertions(+)

diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
index 7a2030b..7b6815d 100644
--- a/drivers/video/console/fbcon.c
+++ b/drivers/video/console/fbcon.c
@@ -3495,11 +3495,84 @@ err:
return count;
}

+static ssize_t show_cursor_blink_ms(struct device *device,
+ struct device_attribute *attr, char *buf)
+{
+ struct fb_info *info;
+ struct fbcon_ops *ops;
+ int idx, ms = -1;
+
+ if (fbcon_has_exited)
+ return 0;
+
+ console_lock();
+ idx = con2fb_map[fg_console];
+
+ if (idx = -1 || registered_fb[idx] = NULL)
+ goto err;
+
+ info = registered_fb[idx];
+ ops = info->fbcon_par;
+
+ if (!ops)
+ goto err;
+
+ ms = jiffies_to_msecs(ops->blink_jiffies);
+
+err:
+ console_unlock();
+ return snprintf(buf, PAGE_SIZE, "%d\n", ms);
+}
+
+static ssize_t store_cursor_blink_ms(struct device *device,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct fb_info *info;
+ struct fbcon_ops *ops;
+ int idx;
+ short ms;
+
+ if (fbcon_has_exited)
+ return count;
+
+ console_lock();
+ idx = con2fb_map[fg_console];
+
+ if (idx = -1 || registered_fb[idx] = NULL)
+ goto err;
+
+ info = registered_fb[idx];
+
+ if (!info->fbcon_par)
+ goto err;
+
+ ops = info->fbcon_par;
+
+ if (!ops)
+ goto err;
+
+ if (!kstrtos16(buf, 0, &ms)) {
+ ops->blink_jiffies = max_t(int, msecs_to_jiffies(ms), 1);
+ if (info->queue.func = fb_flashcursor &&
+ ops->flags & FBCON_FLAGS_CURSOR_TIMER) {
+ fbcon_del_cursor_timer(info);
+ fbcon_add_cursor_timer(info);
+ }
+ }
+
+err:
+ console_unlock();
+ return count;
+}
+
static struct device_attribute device_attrs[] = {
__ATTR(rotate, S_IRUGO|S_IWUSR, show_rotate, store_rotate),
__ATTR(rotate_all, S_IWUSR, NULL, store_rotate_all),
__ATTR(cursor_blink, S_IRUGO|S_IWUSR, show_cursor_blink,
store_cursor_blink),
+ __ATTR(cursor_blink_ms, S_IRUGO|S_IWUSR, show_cursor_blink_ms,
+ store_cursor_blink_ms),
};

static int fbcon_init_device(void)
--
2.1.4