Merge branch '2021-03-12-assorted-improvements' into next

- More log enhancements
- A few warning fixes in some cases
- Secure Channel Protocol 03 (SCP03) support for TEEs

1 files changed, 30 insertions, 1 deletions

diff --git a/doc/develop/logging.rst b/doc/develop/logging.rst
index 60c18c5b3a..f4e925048e 100644
--- a/doc/develop/logging.rst
+++ b/doc/develop/logging.rst
@@ -96,16 +96,45 @@ Also debug() and error() will generate log records  - these use LOG_CATEGORY
 as the category, so you should #define this right at the top of the source
 file to ensure the category is correct.
 
+Generally each log format_string ends with a newline. If it does not, then the
+next log statement will have the LOGRECF_CONT flag set. This can be used to
+continue the statement on the same line as the previous one without emitting
+new header information (such as category/level). This behaviour is implemented
+with log_console. Here is an example that prints a list all on one line with
+the tags at the start:
+
+.. code-block:: c
+
+   log_debug("Here is a list:");
+   for (i = 0; i < count; i++)
+      log_debug(" item %d", i);
+   log_debug("\n");
+
+Also see the special category LOGL_CONT and level LOGC_CONT.
+
 You can also define CONFIG_LOG_ERROR_RETURN to enable the log_ret() macro. This
 can be used whenever your function returns an error value:
 
 .. code-block:: c
 
-   return log_ret(uclass_first_device(UCLASS_MMC, &dev));
+   return log_ret(uclass_first_device_err(UCLASS_MMC, &dev));
 
 This will write a log record when an error code is detected (a value < 0). This
 can make it easier to trace errors that are generated deep in the call stack.
 
+The log_msg_ret() variant will print a short string if CONFIG_LOG_ERROR_RETURN
+is enabled. So long as the string is unique within the function you can normally
+determine exactly which call failed:
+
+.. code-block:: c
+
+   ret = gpio_request_by_name(dev, "cd-gpios", 0, &desc, GPIOD_IS_IN);
+   if (ret)
+      return log_msg_ret("gpio", ret);
+
+Some functions return 0 for success and any other value is an error. For these,
+log_retz() and log_msg_retz() are available.
+
 Convenience functions
 ~~~~~~~~~~~~~~~~~~~~~