[U-Boot] [PATCH v2 08/14] log: Add a console driver

[Simon Glass]

It is useful to display log messages on the console. Add a simple driver
to handle this.

Note that this driver outputs to the console, which may be serial or
video. It does not specifically select serial output.

Signed-off-by: Simon Glass <sjg at chromium.org>
Reviewed-by: Bin Meng <bmeng.cn at gmail.com>
---

Changes in v2:
- Update commit message to explain that this is not just for serial output

 common/Kconfig       | 20 ++++++++++++++++++++
 common/Makefile      |  1 +
 common/log_console.c | 23 +++++++++++++++++++++++
 3 files changed, 44 insertions(+)
 create mode 100644 common/log_console.c

diff --git a/common/Kconfig b/common/Kconfig
index ca4a0f7f9b..7fed04a5fb 100644
--- a/common/Kconfig
+++ b/common/Kconfig
@@ -436,6 +436,26 @@ config SPL_LOG_MAX_LEVEL
 	    6 - detail
 	    7 - debug
 
+config LOG_CONSOLE
+	bool "Allow log output to the console"
+	depends on LOG
+	default y
+	help
+	  Enables a log driver which writes log records to the console.
+	  Generally the console is the serial port or LCD display. Only the
+	  log message is shown - other details like level, category, file and
+	  line number are omitted.
+
+config LOG_SPL_CONSOLE
+	bool "Allow log output to the console in SPL"
+	depends on LOG_SPL
+	default y
+	help
+	  Enables a log driver which writes log records to the console.
+	  Generally the console is the serial port or LCD display. Only the
+	  log message is shown - other details like level, category, file and
+	  line number are omitted.
+
 endmenu
 
 config DTB_RESELECT
diff --git a/common/Makefile b/common/Makefile
index 9d52c9623c..6405a4c299 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -129,5 +129,6 @@ obj-$(CONFIG_FSL_DDR_INTERACTIVE) += cli_simple.o cli_readline.o
 obj-$(CONFIG_CMD_DFU) += dfu.o
 obj-y += command.o
 obj-$(CONFIG_$(SPL_)LOG) += log.o
+obj-$(CONFIG_$(SPL_)LOG_CONSOLE) += log_console.o
 obj-y += s_record.o
 obj-y += xyzModem.o
diff --git a/common/log_console.c b/common/log_console.c
new file mode 100644
index 0000000000..5af73bd8be
--- /dev/null
+++ b/common/log_console.c
@@ -0,0 +1,23 @@
+/*
+ * Logging support
+ *
+ * Copyright (c) 2017 Google, Inc
+ * Written by Simon Glass <sjg at chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <log.h>
+
+static int log_console_emit(struct log_device *ldev, struct log_rec *rec)
+{
+	puts(rec->msg);
+
+	return 0;
+}
+
+LOG_DRIVER(console) = {
+	.name	= "console",
+	.emit	= log_console_emit,
+};
-- 
2.14.1.992.g2c7b836f3a-goog