There is no need to call ->start() for already started device. All the same,
there is no need to call ->stop() for devices still in use.
For now enforce this only for IOMUX case.
Cc: Simon Glass <s...@chromium.org>
Signed-off-by: Andy Shevchenko <andriy.shevche...@linux.intel.com>
---
v3: renamed new function and added a documentation for it
common/console.c | 37 +++++++++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/common/console.c b/common/console.c
index 9973f96e7629..e5fd214ae86f 100644
--- a/common/console.c
+++ b/common/console.c
@@ -174,6 +174,32 @@ static struct stdio_dev *tstcdev;
struct stdio_dev **console_devices[MAX_FILES];
int cd_count[MAX_FILES];
+/**
+ * console_needs_start_stop() - check if we need to start or stop the STDIO
device
+ * @file: STDIO file
+ * @sdev: STDIO device in question
+ *
+ * This function checks if we need to start or stop the stdio device used for
+ * a console. For IOMUX case it simply enforces one time start and one time
+ * stop of the device independently of how many STDIO files are using it. In
+ * other words, we start console once before first STDIO device wants it and
+ * stop after the last is gone.
+ */
+static bool console_needs_start_stop(int file, struct stdio_dev *sdev)
+{
+ int i, j;
+
+ for (i = 0; i < ARRAY_SIZE(cd_count); i++) {
+ if (i == file)
+ continue;
+
+ for (j = 0; j < cd_count[i]; j++)
+ if (console_devices[i][j] == sdev)
+ return false;
+ }
+ return true;
+}
+
/*
* This depends on tstc() always being called before getchar().
* This is guaranteed to be true because this routine is called
@@ -272,6 +298,11 @@ static inline void console_doenv(int file, struct
stdio_dev *dev)
}
#endif
#else
+static inline bool console_needs_start_stop(int file, struct stdio_dev *sdev)
+{
+ return true;
+}
+
static inline int console_getc(int file)
{
return stdio_devices[file]->getc(stdio_devices[file]);
@@ -310,6 +341,9 @@ int console_start(int file, struct stdio_dev *sdev)
{
int error;
+ if (!console_needs_start_stop(file, sdev))
+ return 0;
+
/* Start new device */
if (sdev->start) {
error = sdev->start(sdev);
@@ -322,6 +356,9 @@ int console_start(int file, struct stdio_dev *sdev)
void console_stop(int file, struct stdio_dev *sdev)
{
+ if (!console_needs_start_stop(file, sdev))
+ return;
+
if (sdev->stop)
sdev->stop(sdev);
}
--
2.29.2
