[PATCH 07/10] fblog: forward kernel log messages to all framebuffers

[David Herrmann <dh.herrmann@googlemail.com>]

This provides a console-driver that forwards all log messages to all
framebuffers and redraws them.

To avoid redrawing multiple times in short intervals, we could use a
work-queue here by simply pushing the task onto the system work-queue.
However, fblog is not performance critical and only used for debugging so
we avoid the complexity for now. This may change in the future, though.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
---
 drivers/video/console/fblog.c |   19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/drivers/video/console/fblog.c b/drivers/video/console/fblog.c
index 9b05c56..5297eca 100644
--- a/drivers/video/console/fblog.c
+++ b/drivers/video/console/fblog.c
@@ -449,6 +449,25 @@ static void fblog_deactivate(void)
 	fblog_unregister_all();
 }
 
+static void fblog_con_write(struct console *con, const char *buf,
+			    unsigned int len)
+{
+	int i;
+
+	for (i = 0; i < FB_MAX; ++i) {
+		if (fblog_fbs[i]) {
+			fblog_buf_write(&fblog_fbs[i]->buf, buf, len);
+			fblog_redraw(fblog_fbs[i]);
+		}
+	}
+}
+
+static struct console fblog_con_driver = {
+	.name = "fblog",
+	.write = fblog_con_write,
+	.flags = CON_PRINTBUFFER | CON_ENABLED,
+};
+
 static ssize_t fblog_dev_active_show(struct device *dev,
 				     struct device_attribute *attr,
 				     char *buf)
-- 
1.7.10.4